Merge pull request #9785 from vnen/update-zstd

zstd: Update to upstream version 1.3.0

19 files changed, 2743 insertions, 1191 deletions

diff --git a/thirdparty/zstd/README.md b/thirdparty/zstd/README.md
index 7caee5fd3f..f37be4542c 100644
--- a/thirdparty/zstd/README.md
+++ b/thirdparty/zstd/README.md
@@ -6,10 +6,17 @@ and a command line utility producing and decoding `.zst` and `.gz` files.
 For other programming languages,
 you can consult a list of known ports on [Zstandard homepage](http://www.zstd.net/#other-languages).
 
-|Branch      |Status   |
-|------------|---------|
-|master      | [![Build Status](https://travis-ci.org/facebook/zstd.svg?branch=master)](https://travis-ci.org/facebook/zstd) |
-|dev         | [![Build Status](https://travis-ci.org/facebook/zstd.svg?branch=dev)](https://travis-ci.org/facebook/zstd) |
+| dev branch status |
+|-------------------|
+| [![Build Status][travisDevBadge]][travisLink]   [![Build status][AppveyorDevBadge]][AppveyorLink]   [![Build status][CircleDevBadge]][CircleLink]
+
+[travisDevBadge]: https://travis-ci.org/facebook/zstd.svg?branch=dev "Continuous Integration test suite"
+[travisLink]: https://travis-ci.org/facebook/zstd
+[AppveyorDevBadge]: https://ci.appveyor.com/api/projects/status/xt38wbdxjk5mrbem/branch/dev?svg=true "Windows test suite"
+[AppveyorLink]: https://ci.appveyor.com/project/YannCollet/zstd-p0yf0
+[CircleDevBadge]: https://circleci.com/gh/facebook/zstd/tree/dev.svg?style=shield "Short test suite"
+[CircleLink]: https://circleci.com/gh/facebook/zstd
+
 
 As a reference, several fast compression algorithms were tested and compared
 on a server running Linux Debian (`Linux version 4.8.0-1-amd64`),
@@ -60,11 +67,11 @@ Previous charts provide results applicable to typical file and stream scenarios
 The smaller the amount of data to compress, the more difficult it is to compress. This problem is common to all compression algorithms, and reason is, compression algorithms learn from past data how to compress future data. But at the beginning of a new data set, there is no "past" to build upon.
 
 To solve this situation, Zstd offers a __training mode__, which can be used to tune the algorithm for a selected type of data.
-Training Zstandard is achieved by provide it with a few samples (one file per sample). The result of this training is stored in a file called "dictionary", which must be loaded before compression and decompression.
+Training Zstandard is achieved by providing it with a few samples (one file per sample). The result of this training is stored in a file called "dictionary", which must be loaded before compression and decompression.
 Using this dictionary, the compression ratio achievable on small data improves dramatically.
 
 The following example uses the `github-users` [sample set](https://github.com/facebook/zstd/releases/tag/v1.1.3), created from [github public API](https://developer.github.com/v3/users/#get-all-users).
-It consists of roughly 10K records weighting about 1KB each.
+It consists of roughly 10K records weighing about 1KB each.
 
 Compression Ratio | Compression Speed | Decompression Speed
 ------------------|-------------------|--------------------
diff --git a/thirdparty/zstd/common/bitstream.h b/thirdparty/zstd/common/bitstream.h
index ca42850df3..07b85026c9 100644
--- a/thirdparty/zstd/common/bitstream.h
+++ b/thirdparty/zstd/common/bitstream.h
@@ -39,7 +39,6 @@
 extern "C" {
 #endif
 
-
 /*
 *  This API consists of small unitary functions, which must be inlined for best performance.
 *  Since link-time-optimization is not available for all compilers,
@@ -59,7 +58,9 @@ extern "C" {
 #if defined(BIT_DEBUG) && (BIT_DEBUG>=1)
 #  include <assert.h>
 #else
-#  define assert(condition) ((void)0)
+#  ifndef assert
+#    define assert(condition) ((void)0)
+#  endif
 #endif
 
 
@@ -74,6 +75,7 @@ extern "C" {
 #define STREAM_ACCUMULATOR_MIN_64  57
 #define STREAM_ACCUMULATOR_MIN    ((U32)(MEM_32bits() ? STREAM_ACCUMULATOR_MIN_32 : STREAM_ACCUMULATOR_MIN_64))
 
+
 /*-******************************************
 *  bitStream encoding API (write forward)
 ********************************************/
@@ -303,13 +305,25 @@ MEM_STATIC size_t BIT_initDStream(BIT_DStream_t* bitD, const void* srcBuffer, si
         bitD->bitContainer = *(const BYTE*)(bitD->start);
         switch(srcSize)
         {
-            case 7: bitD->bitContainer += (size_t)(((const BYTE*)(srcBuffer))[6]) << (sizeof(bitD->bitContainer)*8 - 16);
-            case 6: bitD->bitContainer += (size_t)(((const BYTE*)(srcBuffer))[5]) << (sizeof(bitD->bitContainer)*8 - 24);
-            case 5: bitD->bitContainer += (size_t)(((const BYTE*)(srcBuffer))[4]) << (sizeof(bitD->bitContainer)*8 - 32);
-            case 4: bitD->bitContainer += (size_t)(((const BYTE*)(srcBuffer))[3]) << 24;
-            case 3: bitD->bitContainer += (size_t)(((const BYTE*)(srcBuffer))[2]) << 16;
-            case 2: bitD->bitContainer += (size_t)(((const BYTE*)(srcBuffer))[1]) <<  8;
-            default:;
+	    case 7: bitD->bitContainer += (size_t)(((const BYTE*)(srcBuffer))[6]) << (sizeof(bitD->bitContainer)*8 - 16);
+	            /* fall-through */
+
+	    case 6: bitD->bitContainer += (size_t)(((const BYTE*)(srcBuffer))[5]) << (sizeof(bitD->bitContainer)*8 - 24);
+	            /* fall-through */
+
+	    case 5: bitD->bitContainer += (size_t)(((const BYTE*)(srcBuffer))[4]) << (sizeof(bitD->bitContainer)*8 - 32);
+	            /* fall-through */
+
+	    case 4: bitD->bitContainer += (size_t)(((const BYTE*)(srcBuffer))[3]) << 24;
+	            /* fall-through */
+
+	    case 3: bitD->bitContainer += (size_t)(((const BYTE*)(srcBuffer))[2]) << 16;
+	            /* fall-through */
+
+	    case 2: bitD->bitContainer += (size_t)(((const BYTE*)(srcBuffer))[1]) <<  8;
+	            /* fall-through */
+
+            default: break;
         }
         { BYTE const lastByte = ((const BYTE*)srcBuffer)[srcSize-1];
           bitD->bitsConsumed = lastByte ? 8 - BIT_highbit32(lastByte) : 0;
diff --git a/thirdparty/zstd/common/error_private.c b/thirdparty/zstd/common/error_private.c
index b3287245f1..2d752cd23a 100644
--- a/thirdparty/zstd/common/error_private.c
+++ b/thirdparty/zstd/common/error_private.c
@@ -24,7 +24,8 @@ const char* ERR_getErrorString(ERR_enum code)
     case PREFIX(frameParameter_unsupported): return "Unsupported frame parameter";
     case PREFIX(frameParameter_unsupportedBy32bits): return "Frame parameter unsupported in 32-bits mode";
     case PREFIX(frameParameter_windowTooLarge): return "Frame requires too much memory for decoding";
-    case PREFIX(compressionParameter_unsupported): return "Compression parameter is out of bound";
+    case PREFIX(compressionParameter_unsupported): return "Compression parameter is not supported";
+    case PREFIX(compressionParameter_outOfBound): return "Compression parameter is out of bound";
     case PREFIX(init_missing): return "Context should be init first";
     case PREFIX(memory_allocation): return "Allocation error : not enough memory";
     case PREFIX(stage_wrong): return "Operation not authorized at current processing stage";
@@ -38,6 +39,8 @@ const char* ERR_getErrorString(ERR_enum code)
     case PREFIX(dictionary_corrupted): return "Dictionary is corrupted";
     case PREFIX(dictionary_wrong): return "Dictionary mismatch";
     case PREFIX(dictionaryCreation_failed): return "Cannot create Dictionary from provided samples";
+    case PREFIX(frameIndex_tooLarge): return "Frame index is too large";
+    case PREFIX(seekableIO): return "An I/O error occurred when reading/seeking";
     case PREFIX(maxCode):
     default: return notErrorCode;
     }
diff --git a/thirdparty/zstd/common/huf.h b/thirdparty/zstd/common/huf.h
index 7873ca3d42..dabd359915 100644
--- a/thirdparty/zstd/common/huf.h
+++ b/thirdparty/zstd/common/huf.h
@@ -111,6 +111,18 @@ HUF_PUBLIC_API size_t HUF_compress2 (void* dst, size_t dstCapacity, const void*
 #define HUF_WORKSPACE_SIZE_U32 (HUF_WORKSPACE_SIZE / sizeof(U32))
 HUF_PUBLIC_API size_t HUF_compress4X_wksp (void* dst, size_t dstCapacity, const void* src, size_t srcSize, unsigned maxSymbolValue, unsigned tableLog, void* workSpace, size_t wkspSize);
 
+/**
+ *  The minimum workspace size for the `workSpace` used in
+ *  HUF_readDTableX2_wksp() and HUF_readDTableX4_wksp().
+ *
+ *  The space used depends on HUF_TABLELOG_MAX, ranging from ~1500 bytes when
+ *  HUF_TABLE_LOG_MAX=12 to ~1850 bytes when HUF_TABLE_LOG_MAX=15.
+ *  Buffer overflow errors may potentially occur if code modifications result in
+ *  a required workspace size greater than that specified in the following
+ *  macro.
+ */
+#define HUF_DECOMPRESS_WORKSPACE_SIZE (2 << 10)
+#define HUF_DECOMPRESS_WORKSPACE_SIZE_U32 (HUF_DECOMPRESS_WORKSPACE_SIZE / sizeof(U32))
 
 
 /* ******************************************************************
@@ -170,8 +182,11 @@ size_t HUF_decompress4X4 (void* dst, size_t dstSize, const void* cSrc, size_t cS
 
 size_t HUF_decompress4X_DCtx (HUF_DTable* dctx, void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize);   /**< decodes RLE and uncompressed */
 size_t HUF_decompress4X_hufOnly(HUF_DTable* dctx, void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize); /**< considers RLE and uncompressed as errors */
+size_t HUF_decompress4X_hufOnly_wksp(HUF_DTable* dctx, void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize, void* workSpace, size_t wkspSize); /**< considers RLE and uncompressed as errors */
 size_t HUF_decompress4X2_DCtx(HUF_DTable* dctx, void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize);   /**< single-symbol decoder */
+size_t HUF_decompress4X2_DCtx_wksp(HUF_DTable* dctx, void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize, void* workSpace, size_t wkspSize);   /**< single-symbol decoder */
 size_t HUF_decompress4X4_DCtx(HUF_DTable* dctx, void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize);   /**< double-symbols decoder */
+size_t HUF_decompress4X4_DCtx_wksp(HUF_DTable* dctx, void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize, void* workSpace, size_t wkspSize);   /**< double-symbols decoder */
 
 
 /* ****************************************
@@ -243,7 +258,9 @@ HUF_decompress() does the following:
 U32 HUF_selectDecoder (size_t dstSize, size_t cSrcSize);
 
 size_t HUF_readDTableX2 (HUF_DTable* DTable, const void* src, size_t srcSize);
+size_t HUF_readDTableX2_wksp (HUF_DTable* DTable, const void* src, size_t srcSize, void* workSpace, size_t wkspSize);
 size_t HUF_readDTableX4 (HUF_DTable* DTable, const void* src, size_t srcSize);
+size_t HUF_readDTableX4_wksp (HUF_DTable* DTable, const void* src, size_t srcSize, void* workSpace, size_t wkspSize);
 
 size_t HUF_decompress4X_usingDTable(void* dst, size_t maxDstSize, const void* cSrc, size_t cSrcSize, const HUF_DTable* DTable);
 size_t HUF_decompress4X2_usingDTable(void* dst, size_t maxDstSize, const void* cSrc, size_t cSrcSize, const HUF_DTable* DTable);
@@ -266,8 +283,11 @@ size_t HUF_decompress1X2 (void* dst, size_t dstSize, const void* cSrc, size_t cS
 size_t HUF_decompress1X4 (void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize);   /* double-symbol decoder */
 
 size_t HUF_decompress1X_DCtx (HUF_DTable* dctx, void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize);
+size_t HUF_decompress1X_DCtx_wksp (HUF_DTable* dctx, void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize, void* workSpace, size_t wkspSize);
 size_t HUF_decompress1X2_DCtx(HUF_DTable* dctx, void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize);   /**< single-symbol decoder */
+size_t HUF_decompress1X2_DCtx_wksp(HUF_DTable* dctx, void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize, void* workSpace, size_t wkspSize);   /**< single-symbol decoder */
 size_t HUF_decompress1X4_DCtx(HUF_DTable* dctx, void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize);   /**< double-symbols decoder */
+size_t HUF_decompress1X4_DCtx_wksp(HUF_DTable* dctx, void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize, void* workSpace, size_t wkspSize);   /**< double-symbols decoder */
 
 size_t HUF_decompress1X_usingDTable(void* dst, size_t maxDstSize, const void* cSrc, size_t cSrcSize, const HUF_DTable* DTable);   /**< automatic selection of sing or double symbol decoder, based on DTable */
 size_t HUF_decompress1X2_usingDTable(void* dst, size_t maxDstSize, const void* cSrc, size_t cSrcSize, const HUF_DTable* DTable);
diff --git a/thirdparty/zstd/common/mem.h b/thirdparty/zstd/common/mem.h
index 4773a8b930..b0e5bf60b4 100644
--- a/thirdparty/zstd/common/mem.h
+++ b/thirdparty/zstd/common/mem.h
@@ -352,20 +352,6 @@ MEM_STATIC void MEM_writeBEST(void* memPtr, size_t val)
 }
 
 
-/* function safe only for comparisons */
-MEM_STATIC U32 MEM_readMINMATCH(const void* memPtr, U32 length)
-{
-    switch (length)
-    {
-    default :
-    case 4 : return MEM_read32(memPtr);
-    case 3 : if (MEM_isLittleEndian())
-                return MEM_read32(memPtr)<<8;
-             else
-                return MEM_read32(memPtr)>>8;
-    }
-}
-
 #if defined (__cplusplus)
 }
 #endif
diff --git a/thirdparty/zstd/common/pool.c b/thirdparty/zstd/common/pool.c
index e439fe1b0d..749fa4f2f7 100644
--- a/thirdparty/zstd/common/pool.c
+++ b/thirdparty/zstd/common/pool.c
@@ -146,6 +146,13 @@ void POOL_free(POOL_ctx *ctx) {
     free(ctx);
 }
 
+size_t POOL_sizeof(POOL_ctx *ctx) {
+    if (ctx==NULL) return 0;  /* supports sizeof NULL */
+    return sizeof(*ctx)
+        + ctx->queueSize * sizeof(POOL_job)
+        + ctx->numThreads * sizeof(pthread_t);
+}
+
 void POOL_add(void *ctxVoid, POOL_function function, void *opaque) {
     POOL_ctx *ctx = (POOL_ctx *)ctxVoid;
     if (!ctx) { return; }
@@ -191,4 +198,9 @@ void POOL_add(void *ctx, POOL_function function, void *opaque) {
   function(opaque);
 }
 
+size_t POOL_sizeof(POOL_ctx *ctx) {
+    if (ctx==NULL) return 0;  /* supports sizeof NULL */
+    return sizeof(*ctx);
+}
+
 #endif  /* ZSTD_MULTITHREAD */
diff --git a/thirdparty/zstd/common/pool.h b/thirdparty/zstd/common/pool.h
index 50cb25b12c..386cd674b7 100644
--- a/thirdparty/zstd/common/pool.h
+++ b/thirdparty/zstd/common/pool.h
@@ -32,6 +32,11 @@ POOL_ctx *POOL_create(size_t numThreads, size_t queueSize);
 */
 void POOL_free(POOL_ctx *ctx);
 
+/*! POOL_sizeof() :
+    return memory usage of pool returned by POOL_create().
+*/
+size_t POOL_sizeof(POOL_ctx *ctx);
+
 /*! POOL_function :
     The function type that can be added to a thread pool.
 */
diff --git a/thirdparty/zstd/common/threading.c b/thirdparty/zstd/common/threading.c
index 32d58796a9..141376c561 100644
--- a/thirdparty/zstd/common/threading.c
+++ b/thirdparty/zstd/common/threading.c
@@ -1,4 +1,3 @@
-
 /**
  * Copyright (c) 2016 Tino Reichardt
  * All rights reserved.
diff --git a/thirdparty/zstd/common/zstd_common.c b/thirdparty/zstd/common/zstd_common.c
index 8408a589ae..f681672381 100644
--- a/thirdparty/zstd/common/zstd_common.c
+++ b/thirdparty/zstd/common/zstd_common.c
@@ -12,16 +12,19 @@
 /*-*************************************
 *  Dependencies
 ***************************************/
-#include <stdlib.h>         /* malloc */
+#include <stdlib.h>      /* malloc, calloc, free */
+#include <string.h>      /* memset */
 #include "error_private.h"
 #define ZSTD_STATIC_LINKING_ONLY
-#include "zstd.h"           /* declaration of ZSTD_isError, ZSTD_getErrorName, ZSTD_getErrorCode, ZSTD_getErrorString, ZSTD_versionNumber */
+#include "zstd.h"
 
 
 /*-****************************************
 *  Version
 ******************************************/
-unsigned ZSTD_versionNumber (void) { return ZSTD_VERSION_NUMBER; }
+unsigned ZSTD_versionNumber(void) { return ZSTD_VERSION_NUMBER; }
+
+const char* ZSTD_versionString(void) { return ZSTD_VERSION_STRING; }
 
 
 /*-****************************************
@@ -47,27 +50,31 @@ const char* ZSTD_getErrorString(ZSTD_ErrorCode code) { return ERR_getErrorString
 /*=**************************************************************
 *  Custom allocator
 ****************************************************************/
-/* default uses stdlib */
-void* ZSTD_defaultAllocFunction(void* opaque, size_t size)
-{
-    void* address = malloc(size);
-    (void)opaque;
-    return address;
-}
-
-void ZSTD_defaultFreeFunction(void* opaque, void* address)
+void* ZSTD_malloc(size_t size, ZSTD_customMem customMem)
 {
-    (void)opaque;
-    free(address);
+    if (customMem.customAlloc)
+        return customMem.customAlloc(customMem.opaque, size);
+    return malloc(size);
 }
 
-void* ZSTD_malloc(size_t size, ZSTD_customMem customMem)
+void* ZSTD_calloc(size_t size, ZSTD_customMem customMem)
 {
-    return customMem.customAlloc(customMem.opaque, size);
+    if (customMem.customAlloc) {
+        /* calloc implemented as malloc+memset;
+         * not as efficient as calloc, but next best guess for custom malloc */
+        void* const ptr = customMem.customAlloc(customMem.opaque, size);
+        memset(ptr, 0, size);
+        return ptr;
+    }
+    return calloc(1, size);
 }
 
 void ZSTD_free(void* ptr, ZSTD_customMem customMem)
 {
-    if (ptr!=NULL)
-        customMem.customFree(customMem.opaque, ptr);
+    if (ptr!=NULL) {
+        if (customMem.customFree)
+            customMem.customFree(customMem.opaque, ptr);
+        else
+            free(ptr);
+    }
 }
diff --git a/thirdparty/zstd/common/zstd_errors.h b/thirdparty/zstd/common/zstd_errors.h
index 3d579d9693..19f1597aa3 100644
--- a/thirdparty/zstd/common/zstd_errors.h
+++ b/thirdparty/zstd/common/zstd_errors.h
@@ -19,10 +19,12 @@ extern "C" {
 
 
 /* =====   ZSTDERRORLIB_API : control library symbols visibility   ===== */
-#if defined(__GNUC__) && (__GNUC__ >= 4)
-#  define ZSTDERRORLIB_VISIBILITY __attribute__ ((visibility ("default")))
-#else
-#  define ZSTDERRORLIB_VISIBILITY
+#ifndef ZSTDERRORLIB_VISIBILITY
+#  if defined(__GNUC__) && (__GNUC__ >= 4)
+#    define ZSTDERRORLIB_VISIBILITY __attribute__ ((visibility ("default")))
+#  else
+#    define ZSTDERRORLIB_VISIBILITY
+#  endif
 #endif
 #if defined(ZSTD_DLL_EXPORT) && (ZSTD_DLL_EXPORT==1)
 #  define ZSTDERRORLIB_API __declspec(dllexport) ZSTDERRORLIB_VISIBILITY
@@ -33,8 +35,11 @@ extern "C" {
 #endif
 
 /*-****************************************
-*  error codes list
-******************************************/
+ *  error codes list
+ *  note : this API is still considered unstable
+ *         it should not be used with a dynamic library
+ *         only static linking is allowed
+ ******************************************/
 typedef enum {
   ZSTD_error_no_error,
   ZSTD_error_GENERIC,
@@ -45,6 +50,7 @@ typedef enum {
   ZSTD_error_frameParameter_unsupportedBy32bits,
   ZSTD_error_frameParameter_windowTooLarge,
   ZSTD_error_compressionParameter_unsupported,
+  ZSTD_error_compressionParameter_outOfBound,
   ZSTD_error_init_missing,
   ZSTD_error_memory_allocation,
   ZSTD_error_stage_wrong,
@@ -58,12 +64,14 @@ typedef enum {
   ZSTD_error_dictionary_corrupted,
   ZSTD_error_dictionary_wrong,
   ZSTD_error_dictionaryCreation_failed,
+  ZSTD_error_frameIndex_tooLarge,
+  ZSTD_error_seekableIO,
   ZSTD_error_maxCode
 } ZSTD_ErrorCode;
 
 /*! ZSTD_getErrorCode() :
     convert a `size_t` function result into a `ZSTD_ErrorCode` enum type,
-    which can be used to compare directly with enum list published into "error_public.h" */
+    which can be used to compare with enum list published above */
 ZSTDERRORLIB_API ZSTD_ErrorCode ZSTD_getErrorCode(size_t functionResult);
 ZSTDERRORLIB_API const char* ZSTD_getErrorString(ZSTD_ErrorCode code);
 
diff --git a/thirdparty/zstd/common/zstd_internal.h b/thirdparty/zstd/common/zstd_internal.h
index 2533333ba8..f2c4e6249f 100644
--- a/thirdparty/zstd/common/zstd_internal.h
+++ b/thirdparty/zstd/common/zstd_internal.h
@@ -18,6 +18,7 @@
 #  include <intrin.h>                    /* For Visual 2005 */
 #  pragma warning(disable : 4100)        /* disable: C4100: unreferenced formal parameter */
 #  pragma warning(disable : 4127)        /* disable: C4127: conditional expression is constant */
+#  pragma warning(disable : 4204)        /* disable: C4204: non-constant aggregate initializer */
 #  pragma warning(disable : 4324)        /* disable: C4324: padded structure */
 #else
 #  if defined (__cplusplus) || defined (__STDC_VERSION__) && __STDC_VERSION__ >= 199901L   /* C99 */
@@ -50,9 +51,42 @@
 #define ZSTD_STATIC_LINKING_ONLY
 #include "zstd.h"
 #ifndef XXH_STATIC_LINKING_ONLY
-#  define XXH_STATIC_LINKING_ONLY   /* XXH64_state_t */
+#  define XXH_STATIC_LINKING_ONLY  /* XXH64_state_t */
+#endif
+#include "xxhash.h"                /* XXH_reset, update, digest */
+
+
+/*-*************************************
+*  Debug
+***************************************/
+#if defined(ZSTD_DEBUG) && (ZSTD_DEBUG>=1)
+#  include <assert.h>
+#else
+#  ifndef assert
+#    define assert(condition) ((void)0)
+#  endif
+#endif
+
+#define ZSTD_STATIC_ASSERT(c) { enum { ZSTD_static_assert = 1/(int)(!!(c)) }; }
+
+#if defined(ZSTD_DEBUG) && (ZSTD_DEBUG>=2)
+#  include <stdio.h>
+/* recommended values for ZSTD_DEBUG display levels :
+ * 1 : no display, enables assert() only
+ * 2 : reserved for currently active debugging path
+ * 3 : events once per object lifetime (CCtx, CDict)
+ * 4 : events once per frame
+ * 5 : events once per block
+ * 6 : events once per sequence (*very* verbose) */
+#  define DEBUGLOG(l, ...) {                         \
+                if (l<=ZSTD_DEBUG) {                 \
+                    fprintf(stderr, __FILE__ ": ");  \
+                    fprintf(stderr, __VA_ARGS__);    \
+                    fprintf(stderr, " \n");          \
+            }   }
+#else
+#  define DEBUGLOG(l, ...)      {}    /* disabled */
 #endif
-#include "xxhash.h"               /* XXH_reset, update, digest */
 
 
 /*-*************************************
@@ -70,7 +104,6 @@
 *  Common constants
 ***************************************/
 #define ZSTD_OPT_NUM    (1<<12)
-#define ZSTD_DICT_MAGIC  0xEC30A437   /* v0.7+ */
 
 #define ZSTD_REP_NUM      3                 /* number of repcodes */
 #define ZSTD_REP_CHECK    (ZSTD_REP_NUM)    /* number of repcodes to check by the optimal parser */
@@ -235,15 +268,10 @@ typedef struct {
 
 const seqStore_t* ZSTD_getSeqStore(const ZSTD_CCtx* ctx);
 void ZSTD_seqToCodes(const seqStore_t* seqStorePtr);
-int ZSTD_isSkipFrame(ZSTD_DCtx* dctx);
 
 /* custom memory allocation functions */
-void* ZSTD_defaultAllocFunction(void* opaque, size_t size);
-void ZSTD_defaultFreeFunction(void* opaque, void* address);
-#ifndef ZSTD_DLL_IMPORT
-static const ZSTD_customMem defaultCustomMem = { ZSTD_defaultAllocFunction, ZSTD_defaultFreeFunction, NULL };
-#endif
 void* ZSTD_malloc(size_t size, ZSTD_customMem customMem);
+void* ZSTD_calloc(size_t size, ZSTD_customMem customMem);
 void ZSTD_free(void* ptr, ZSTD_customMem customMem);
 
 
@@ -281,4 +309,26 @@ MEM_STATIC U32 ZSTD_highbit32(U32 val)
 void ZSTD_invalidateRepCodes(ZSTD_CCtx* cctx);
 
 
+/*! ZSTD_initCStream_internal() :
+ *  Private use only. Init streaming operation.
+ *  expects params to be valid.
+ *  must receive dict, or cdict, or none, but not both.
+ *  @return : 0, or an error code */
+size_t ZSTD_initCStream_internal(ZSTD_CStream* zcs,
+                     const void* dict, size_t dictSize,
+                     const ZSTD_CDict* cdict,
+                     ZSTD_parameters params, unsigned long long pledgedSrcSize);
+
+/*! ZSTD_compressStream_generic() :
+ *  Private use only. To be called from zstdmt_compress.c in single-thread mode. */
+size_t ZSTD_compressStream_generic(ZSTD_CStream* zcs,
+                                   ZSTD_outBuffer* output,
+                                   ZSTD_inBuffer* input,
+                                   ZSTD_EndDirective const flushMode);
+
+/*! ZSTD_getParamsFromCDict() :
+ *  as the name implies */
+ZSTD_parameters ZSTD_getParamsFromCDict(const ZSTD_CDict* cdict);
+
+
 #endif   /* ZSTD_CCOMMON_H_MODULE */
diff --git a/thirdparty/zstd/compress/huf_compress.c b/thirdparty/zstd/compress/huf_compress.c
index fe11aafb8f..7af0789a9c 100644
--- a/thirdparty/zstd/compress/huf_compress.c
+++ b/thirdparty/zstd/compress/huf_compress.c
@@ -266,7 +266,8 @@ static U32 HUF_setMaxHeight(nodeElt* huffNode, U32 lastNonNull, U32 maxNbBits)
                         if (highTotal <= lowTotal) break;
                 }   }
                 /* only triggered when no more rank 1 symbol left => find closest one (note : there is necessarily at least one !) */
-                while ((nBitsToDecrease<=HUF_TABLELOG_MAX) && (rankLast[nBitsToDecrease] == noSymbol))  /* HUF_MAX_TABLELOG test just to please gcc 5+; but it should not be necessary */
+                /* HUF_MAX_TABLELOG test just to please gcc 5+; but it should not be necessary */
+                while ((nBitsToDecrease<=HUF_TABLELOG_MAX) && (rankLast[nBitsToDecrease] == noSymbol))
                     nBitsToDecrease ++;
                 totalCost -= 1 << (nBitsToDecrease-1);
                 if (rankLast[nBitsToDecrease-1] == noSymbol)
@@ -463,12 +464,15 @@ size_t HUF_compress1X_usingCTable(void* dst, size_t dstSize, const void* src, si
     {
         case 3 : HUF_encodeSymbol(&bitC, ip[n+ 2], CTable);
                  HUF_FLUSHBITS_2(&bitC);
+		 /* fall-through */
         case 2 : HUF_encodeSymbol(&bitC, ip[n+ 1], CTable);
                  HUF_FLUSHBITS_1(&bitC);
+		 /* fall-through */
         case 1 : HUF_encodeSymbol(&bitC, ip[n+ 0], CTable);
                  HUF_FLUSHBITS(&bitC);
-        case 0 :
-        default: ;
+		 /* fall-through */
+        case 0 : /* fall-through */
+        default: break;
     }
 
     for (; n>0; n-=4) {  /* note : n&3==0 at this stage */
diff --git a/thirdparty/zstd/compress/zstd_compress.c b/thirdparty/zstd/compress/zstd_compress.c
index c08b315dab..9300357f2d 100644
--- a/thirdparty/zstd/compress/zstd_compress.c
+++ b/thirdparty/zstd/compress/zstd_compress.c
@@ -9,6 +9,14 @@
 
 
 /*-*************************************
+*  Tuning parameters
+***************************************/
+#ifndef ZSTD_CLEVEL_DEFAULT
+#  define ZSTD_CLEVEL_DEFAULT 3
+#endif
+
+
+/*-*************************************
 *  Dependencies
 ***************************************/
 #include <string.h>         /* memset */
@@ -18,26 +26,7 @@
 #define HUF_STATIC_LINKING_ONLY
 #include "huf.h"
 #include "zstd_internal.h"  /* includes zstd.h */
-
-
-/*-*************************************
-*  Debug
-***************************************/
-#if defined(ZSTD_DEBUG) && (ZSTD_DEBUG>=1)
-#  include <assert.h>
-#else
-#  define assert(condition) ((void)0)
-#endif
-
-#define ZSTD_STATIC_ASSERT(c) { enum { ZSTD_static_assert = 1/(int)(!!(c)) }; }
-
-#if defined(ZSTD_DEBUG) && (ZSTD_DEBUG>=2)
-#  include <stdio.h>
-   static unsigned g_debugLevel = ZSTD_DEBUG;
-#  define DEBUGLOG(l, ...) if (l<=g_debugLevel) { fprintf(stderr, __FILE__ ": "); fprintf(stderr, __VA_ARGS__); fprintf(stderr, " \n"); }
-#else
-#  define DEBUGLOG(l, ...)      {}    /* disabled */
-#endif
+#include "zstdmt_compress.h"
 
 
 /*-*************************************
@@ -79,6 +68,15 @@ static void ZSTD_resetSeqStore(seqStore_t* ssPtr)
 /*-*************************************
 *  Context memory management
 ***************************************/
+typedef enum { zcss_init=0, zcss_load, zcss_flush } ZSTD_cStreamStage;
+
+struct ZSTD_CDict_s {
+    void* dictBuffer;
+    const void* dictContent;
+    size_t dictContentSize;
+    ZSTD_CCtx* refContext;
+};  /* typedef'd to ZSTD_CDict within "zstd.h" */
+
 struct ZSTD_CCtx_s {
     const BYTE* nextSrc;    /* next block here to continue on current prefix */
     const BYTE* base;       /* All regular indexes relative to this position */
@@ -90,19 +88,21 @@ struct ZSTD_CCtx_s {
     U32   hashLog3;         /* dispatch table : larger == faster, more memory */
     U32   loadedDictEnd;    /* index of end of dictionary */
     U32   forceWindow;      /* force back-references to respect limit of 1<<wLog, even for dictionary */
-    U32   forceRawDict;     /* Force loading dictionary in "content-only" mode (no header analysis) */
     ZSTD_compressionStage_e stage;
     U32   rep[ZSTD_REP_NUM];
     U32   repToConfirm[ZSTD_REP_NUM];
     U32   dictID;
-    ZSTD_parameters params;
+    int   compressionLevel;
+    ZSTD_parameters requestedParams;
+    ZSTD_parameters appliedParams;
     void* workSpace;
     size_t workSpaceSize;
     size_t blockSize;
-    U64 frameContentSize;
+    U64 pledgedSrcSizePlusOne;  /* this way, 0 (default) == unknown */
     U64 consumedSrcSize;
     XXH64_state_t xxhState;
     ZSTD_customMem customMem;
+    size_t staticSize;
 
     seqStore_t seqStore;    /* sequences storage ptrs */
     U32* hashTable;
@@ -115,31 +115,92 @@ struct ZSTD_CCtx_s {
     FSE_CTable* matchlengthCTable;
     FSE_CTable* litlengthCTable;
     unsigned* entropyScratchSpace;
+
+    /* streaming */
+    char*  inBuff;
+    size_t inBuffSize;
+    size_t inToCompress;
+    size_t inBuffPos;
+    size_t inBuffTarget;
+    char*  outBuff;
+    size_t outBuffSize;
+    size_t outBuffContentSize;
+    size_t outBuffFlushedSize;
+    ZSTD_cStreamStage streamStage;
+    U32    frameEnded;
+
+    /* Dictionary */
+    ZSTD_dictMode_e dictMode; /* select restricting dictionary to "rawContent" or "fullDict" only */
+    U32 dictContentByRef;
+    ZSTD_CDict* cdictLocal;
+    const ZSTD_CDict* cdict;
+    const void* prefix;
+    size_t prefixSize;
+
+    /* Multi-threading */
+    U32 nbThreads;
+    ZSTDMT_CCtx* mtctx;
 };
 
+
 ZSTD_CCtx* ZSTD_createCCtx(void)
 {
-    return ZSTD_createCCtx_advanced(defaultCustomMem);
+    return ZSTD_createCCtx_advanced(ZSTD_defaultCMem);
 }
 
 ZSTD_CCtx* ZSTD_createCCtx_advanced(ZSTD_customMem customMem)
 {
     ZSTD_CCtx* cctx;
 
-    if (!customMem.customAlloc && !customMem.customFree) customMem = defaultCustomMem;
-    if (!customMem.customAlloc || !customMem.customFree) return NULL;
+    if (!customMem.customAlloc ^ !customMem.customFree) return NULL;
 
-    cctx = (ZSTD_CCtx*) ZSTD_malloc(sizeof(ZSTD_CCtx), customMem);
+    cctx = (ZSTD_CCtx*) ZSTD_calloc(sizeof(ZSTD_CCtx), customMem);
     if (!cctx) return NULL;
-    memset(cctx, 0, sizeof(ZSTD_CCtx));
     cctx->customMem = customMem;
+    cctx->compressionLevel = ZSTD_CLEVEL_DEFAULT;
+    ZSTD_STATIC_ASSERT(zcss_init==0);
+    ZSTD_STATIC_ASSERT(ZSTD_CONTENTSIZE_UNKNOWN==(0ULL - 1));
+    return cctx;
+}
+
+ZSTD_CCtx* ZSTD_initStaticCCtx(void *workspace, size_t workspaceSize)
+{
+    ZSTD_CCtx* cctx = (ZSTD_CCtx*) workspace;
+    if (workspaceSize <= sizeof(ZSTD_CCtx)) return NULL;  /* minimum size */
+    if ((size_t)workspace & 7) return NULL;  /* must be 8-aligned */
+    memset(workspace, 0, workspaceSize);   /* may be a bit generous, could memset be smaller ? */
+    cctx->staticSize = workspaceSize;
+    cctx->workSpace = (void*)(cctx+1);
+    cctx->workSpaceSize = workspaceSize - sizeof(ZSTD_CCtx);
+
+    /* entropy space (never moves) */
+    /* note : this code should be shared with resetCCtx, rather than copy/pasted */
+    {   void* ptr = cctx->workSpace;
+        cctx->hufCTable = (HUF_CElt*)ptr;
+        ptr = (char*)cctx->hufCTable + hufCTable_size;
+        cctx->offcodeCTable = (FSE_CTable*) ptr;
+        ptr = (char*)ptr + offcodeCTable_size;
+        cctx->matchlengthCTable = (FSE_CTable*) ptr;
+        ptr = (char*)ptr + matchlengthCTable_size;
+        cctx->litlengthCTable = (FSE_CTable*) ptr;
+        ptr = (char*)ptr + litlengthCTable_size;
+        assert(((size_t)ptr & 3) == 0);   /* ensure correct alignment */
+        cctx->entropyScratchSpace = (unsigned*) ptr;
+    }
+
     return cctx;
 }
 
 size_t ZSTD_freeCCtx(ZSTD_CCtx* cctx)
 {
     if (cctx==NULL) return 0;   /* support free on NULL */
+    if (cctx->staticSize) return ERROR(memory_allocation);   /* not compatible with static CCtx */
     ZSTD_free(cctx->workSpace, cctx->customMem);
+    cctx->workSpace = NULL;
+    ZSTD_freeCDict(cctx->cdictLocal);
+    cctx->cdictLocal = NULL;
+    ZSTDMT_freeCCtx(cctx->mtctx);
+    cctx->mtctx = NULL;
     ZSTD_free(cctx, cctx->customMem);
     return 0;   /* reserved as a potential error code in the future */
 }
@@ -147,46 +208,294 @@ size_t ZSTD_freeCCtx(ZSTD_CCtx* cctx)
 size_t ZSTD_sizeof_CCtx(const ZSTD_CCtx* cctx)
 {
     if (cctx==NULL) return 0;   /* support sizeof on NULL */
-    return sizeof(*cctx) + cctx->workSpaceSize;
+    DEBUGLOG(5, "sizeof(*cctx) : %u", (U32)sizeof(*cctx));
+    DEBUGLOG(5, "workSpaceSize : %u", (U32)cctx->workSpaceSize);
+    DEBUGLOG(5, "streaming buffers : %u", (U32)(cctx->outBuffSize + cctx->inBuffSize));
+    DEBUGLOG(5, "inner MTCTX : %u", (U32)ZSTDMT_sizeof_CCtx(cctx->mtctx));
+    return sizeof(*cctx) + cctx->workSpaceSize
+           + ZSTD_sizeof_CDict(cctx->cdictLocal)
+           + cctx->outBuffSize + cctx->inBuffSize
+           + ZSTDMT_sizeof_CCtx(cctx->mtctx);
 }
 
+size_t ZSTD_sizeof_CStream(const ZSTD_CStream* zcs)
+{
+    return ZSTD_sizeof_CCtx(zcs);  /* same object */
+}
+
+/* private API call, for dictBuilder only */
+const seqStore_t* ZSTD_getSeqStore(const ZSTD_CCtx* ctx) { return &(ctx->seqStore); }
+
+static ZSTD_parameters ZSTD_getParamsFromCCtx(const ZSTD_CCtx* cctx) { return cctx->appliedParams; }
+
+/* older variant; will be deprecated */
 size_t ZSTD_setCCtxParameter(ZSTD_CCtx* cctx, ZSTD_CCtxParameter param, unsigned value)
 {
     switch(param)
     {
     case ZSTD_p_forceWindow : cctx->forceWindow = value>0; cctx->loadedDictEnd = 0; return 0;
-    case ZSTD_p_forceRawDict : cctx->forceRawDict = value>0; return 0;
+    ZSTD_STATIC_ASSERT(ZSTD_dm_auto==0);
+    ZSTD_STATIC_ASSERT(ZSTD_dm_rawContent==1);
+    case ZSTD_p_forceRawDict : cctx->dictMode = (ZSTD_dictMode_e)(value>0); return 0;
     default: return ERROR(parameter_unknown);
     }
 }
 
-const seqStore_t* ZSTD_getSeqStore(const ZSTD_CCtx* ctx)   /* hidden interface */
+
+#define ZSTD_CLEVEL_CUSTOM 999
+static void ZSTD_cLevelToCParams(ZSTD_CCtx* cctx)
 {
-    return &(ctx->seqStore);
+    if (cctx->compressionLevel==ZSTD_CLEVEL_CUSTOM) return;
+    cctx->requestedParams.cParams = ZSTD_getCParams(cctx->compressionLevel,
+                                            cctx->pledgedSrcSizePlusOne-1, 0);
+    cctx->compressionLevel = ZSTD_CLEVEL_CUSTOM;
 }
 
-static ZSTD_parameters ZSTD_getParamsFromCCtx(const ZSTD_CCtx* cctx)
+#define CLAMPCHECK(val,min,max) {                       \
+    if (((val)<(min)) | ((val)>(max))) {                \
+        return ERROR(compressionParameter_outOfBound);  \
+}   }
+
+size_t ZSTD_CCtx_setParameter(ZSTD_CCtx* cctx, ZSTD_cParameter param, unsigned value)
 {
-    return cctx->params;
+    if (cctx->streamStage != zcss_init) return ERROR(stage_wrong);
+
+    switch(param)
+    {
+    case ZSTD_p_compressionLevel :
+        if ((int)value > ZSTD_maxCLevel()) value = ZSTD_maxCLevel();   /* cap max compression level */
+        if (value == 0) return 0;  /* special value : 0 means "don't change anything" */
+        if (cctx->cdict) return ERROR(stage_wrong);
+        cctx->compressionLevel = value;
+        return 0;
+
+    case ZSTD_p_windowLog :
+        DEBUGLOG(5, "setting ZSTD_p_windowLog = %u (cdict:%u)",
+                    value, (cctx->cdict!=NULL));
+        if (value == 0) return 0;  /* special value : 0 means "don't change anything" */
+        if (cctx->cdict) return ERROR(stage_wrong);
+        CLAMPCHECK(value, ZSTD_WINDOWLOG_MIN, ZSTD_WINDOWLOG_MAX);
+        ZSTD_cLevelToCParams(cctx);
+        cctx->requestedParams.cParams.windowLog = value;
+        return 0;
+
+    case ZSTD_p_hashLog :
+        if (value == 0) return 0;  /* special value : 0 means "don't change anything" */
+        if (cctx->cdict) return ERROR(stage_wrong);
+        CLAMPCHECK(value, ZSTD_HASHLOG_MIN, ZSTD_HASHLOG_MAX);
+        ZSTD_cLevelToCParams(cctx);
+        cctx->requestedParams.cParams.hashLog = value;
+        return 0;
+
+    case ZSTD_p_chainLog :
+        if (value == 0) return 0;  /* special value : 0 means "don't change anything" */
+        if (cctx->cdict) return ERROR(stage_wrong);
+        CLAMPCHECK(value, ZSTD_CHAINLOG_MIN, ZSTD_CHAINLOG_MAX);
+        ZSTD_cLevelToCParams(cctx);
+        cctx->requestedParams.cParams.chainLog = value;
+        return 0;
+
+    case ZSTD_p_searchLog :
+        if (value == 0) return 0;  /* special value : 0 means "don't change anything" */
+        if (cctx->cdict) return ERROR(stage_wrong);
+        CLAMPCHECK(value, ZSTD_SEARCHLOG_MIN, ZSTD_SEARCHLOG_MAX);
+        ZSTD_cLevelToCParams(cctx);
+        cctx->requestedParams.cParams.searchLog = value;
+        return 0;
+
+    case ZSTD_p_minMatch :
+        if (value == 0) return 0;  /* special value : 0 means "don't change anything" */
+        if (cctx->cdict) return ERROR(stage_wrong);
+        CLAMPCHECK(value, ZSTD_SEARCHLENGTH_MIN, ZSTD_SEARCHLENGTH_MAX);
+        ZSTD_cLevelToCParams(cctx);
+        cctx->requestedParams.cParams.searchLength = value;
+        return 0;
+
+    case ZSTD_p_targetLength :
+        if (value == 0) return 0;  /* special value : 0 means "don't change anything" */
+        if (cctx->cdict) return ERROR(stage_wrong);
+        CLAMPCHECK(value, ZSTD_TARGETLENGTH_MIN, ZSTD_TARGETLENGTH_MAX);
+        ZSTD_cLevelToCParams(cctx);
+        cctx->requestedParams.cParams.targetLength = value;
+        return 0;
+
+    case ZSTD_p_compressionStrategy :
+        if (value == 0) return 0;  /* special value : 0 means "don't change anything" */
+        if (cctx->cdict) return ERROR(stage_wrong);
+        CLAMPCHECK(value, (unsigned)ZSTD_fast, (unsigned)ZSTD_btultra);
+        ZSTD_cLevelToCParams(cctx);
+        cctx->requestedParams.cParams.strategy = (ZSTD_strategy)value;
+        return 0;
+
+    case ZSTD_p_contentSizeFlag :
+        DEBUGLOG(5, "set content size flag = %u", (value>0));
+        /* Content size written in frame header _when known_ (default:1) */
+        cctx->requestedParams.fParams.contentSizeFlag = value>0;
+        return 0;
+
+    case ZSTD_p_checksumFlag :
+        /* A 32-bits content checksum will be calculated and written at end of frame (default:0) */
+        cctx->requestedParams.fParams.checksumFlag = value>0;
+        return 0;
+
+    case ZSTD_p_dictIDFlag : /* When applicable, dictionary's dictID is provided in frame header (default:1) */
+        DEBUGLOG(5, "set dictIDFlag = %u", (value>0));
+        cctx->requestedParams.fParams.noDictIDFlag = (value==0);
+        return 0;
+
+    /* Dictionary parameters */
+    case ZSTD_p_dictMode :
+        if (cctx->cdict) return ERROR(stage_wrong);  /* must be set before loading */
+        /* restrict dictionary mode, to "rawContent" or "fullDict" only */
+        ZSTD_STATIC_ASSERT((U32)ZSTD_dm_fullDict > (U32)ZSTD_dm_rawContent);
+        if (value > (unsigned)ZSTD_dm_fullDict)
+            return ERROR(compressionParameter_outOfBound);
+        cctx->dictMode = (ZSTD_dictMode_e)value;
+        return 0;
+
+    case ZSTD_p_refDictContent :
+        if (cctx->cdict) return ERROR(stage_wrong);  /* must be set before loading */
+        /* dictionary content will be referenced, instead of copied */
+        cctx->dictContentByRef = value>0;
+        return 0;
+
+    case ZSTD_p_forceMaxWindow :  /* Force back-references to remain < windowSize,
+                                   * even when referencing into Dictionary content
+                                   * default : 0 when using a CDict, 1 when using a Prefix */
+        cctx->forceWindow = value>0;
+        cctx->loadedDictEnd = 0;
+        return 0;
+
+    case ZSTD_p_nbThreads:
+        if (value==0) return 0;
+        DEBUGLOG(5, " setting nbThreads : %u", value);
+#ifndef ZSTD_MULTITHREAD
+        if (value > 1) return ERROR(compressionParameter_unsupported);
+#endif
+        if ((value>1) && (cctx->nbThreads != value)) {
+            if (cctx->staticSize)  /* MT not compatible with static alloc */
+                return ERROR(compressionParameter_unsupported);
+            ZSTDMT_freeCCtx(cctx->mtctx);
+            cctx->nbThreads = 1;
+            cctx->mtctx = ZSTDMT_createCCtx(value);
+            if (cctx->mtctx == NULL) return ERROR(memory_allocation);
+        }
+        cctx->nbThreads = value;
+        return 0;
+
+    case ZSTD_p_jobSize:
+        if (cctx->nbThreads <= 1) return ERROR(compressionParameter_unsupported);
+        assert(cctx->mtctx != NULL);
+        return ZSTDMT_setMTCtxParameter(cctx->mtctx, ZSTDMT_p_sectionSize, value);
+
+    case ZSTD_p_overlapSizeLog:
+        DEBUGLOG(5, " setting overlap with nbThreads == %u", cctx->nbThreads);
+        if (cctx->nbThreads <= 1) return ERROR(compressionParameter_unsupported);
+        assert(cctx->mtctx != NULL);
+        return ZSTDMT_setMTCtxParameter(cctx->mtctx, ZSTDMT_p_overlapSectionLog, value);
+
+    default: return ERROR(parameter_unknown);
+    }
+}
+
+ZSTDLIB_API size_t ZSTD_CCtx_setPledgedSrcSize(ZSTD_CCtx* cctx, unsigned long long pledgedSrcSize)
+{
+    DEBUGLOG(5, " setting pledgedSrcSize to %u", (U32)pledgedSrcSize);
+    if (cctx->streamStage != zcss_init) return ERROR(stage_wrong);
+    cctx->pledgedSrcSizePlusOne = pledgedSrcSize+1;
+    return 0;
+}
+
+ZSTDLIB_API size_t ZSTD_CCtx_loadDictionary(ZSTD_CCtx* cctx, const void* dict, size_t dictSize)
+{
+    if (cctx->streamStage != zcss_init) return ERROR(stage_wrong);
+    if (cctx->staticSize) return ERROR(memory_allocation);  /* no malloc for static CCtx */
+    DEBUGLOG(5, "load dictionary of size %u", (U32)dictSize);
+    ZSTD_freeCDict(cctx->cdictLocal);  /* in case one already exists */
+    if (dict==NULL || dictSize==0) {   /* no dictionary mode */
+        cctx->cdictLocal = NULL;
+        cctx->cdict = NULL;
+    } else {
+        ZSTD_compressionParameters const cParams =
+                cctx->compressionLevel == ZSTD_CLEVEL_CUSTOM ?
+                cctx->requestedParams.cParams :
+                ZSTD_getCParams(cctx->compressionLevel, 0, dictSize);
+        cctx->cdictLocal = ZSTD_createCDict_advanced(
+                                dict, dictSize,
+                                cctx->dictContentByRef, cctx->dictMode,
+                                cParams, cctx->customMem);
+        cctx->cdict = cctx->cdictLocal;
+        if (cctx->cdictLocal == NULL)
+            return ERROR(memory_allocation);
+    }
+    return 0;
+}
+
+size_t ZSTD_CCtx_refCDict(ZSTD_CCtx* cctx, const ZSTD_CDict* cdict)
+{
+    if (cctx->streamStage != zcss_init) return ERROR(stage_wrong);
+    cctx->cdict = cdict;
+    cctx->prefix = NULL;   /* exclusive */
+    cctx->prefixSize = 0;
+    return 0;
+}
+
+size_t ZSTD_CCtx_refPrefix(ZSTD_CCtx* cctx, const void* prefix, size_t prefixSize)
+{
+    if (cctx->streamStage != zcss_init) return ERROR(stage_wrong);
+    cctx->cdict = NULL;   /* prefix discards any prior cdict */
+    cctx->prefix = prefix;
+    cctx->prefixSize = prefixSize;
+    return 0;
+}
+
+static void ZSTD_startNewCompression(ZSTD_CCtx* cctx)
+{
+    cctx->streamStage = zcss_init;
+    cctx->pledgedSrcSizePlusOne = 0;
 }
 
+/*! ZSTD_CCtx_reset() :
+ *  Also dumps dictionary */
+void ZSTD_CCtx_reset(ZSTD_CCtx* cctx)
+{
+    ZSTD_startNewCompression(cctx);
+    cctx->cdict = NULL;
+}
 
-/** ZSTD_checkParams() :
-    ensure param values remain within authorized range.
+/** ZSTD_checkCParams() :
+    control CParam values remain within authorized range.
     @return : 0, or an error code if one value is beyond authorized range */
 size_t ZSTD_checkCParams(ZSTD_compressionParameters cParams)
 {
-#   define CLAMPCHECK(val,min,max) { if ((val<min) | (val>max)) return ERROR(compressionParameter_unsupported); }
     CLAMPCHECK(cParams.windowLog, ZSTD_WINDOWLOG_MIN, ZSTD_WINDOWLOG_MAX);
     CLAMPCHECK(cParams.chainLog, ZSTD_CHAINLOG_MIN, ZSTD_CHAINLOG_MAX);
     CLAMPCHECK(cParams.hashLog, ZSTD_HASHLOG_MIN, ZSTD_HASHLOG_MAX);
     CLAMPCHECK(cParams.searchLog, ZSTD_SEARCHLOG_MIN, ZSTD_SEARCHLOG_MAX);
     CLAMPCHECK(cParams.searchLength, ZSTD_SEARCHLENGTH_MIN, ZSTD_SEARCHLENGTH_MAX);
     CLAMPCHECK(cParams.targetLength, ZSTD_TARGETLENGTH_MIN, ZSTD_TARGETLENGTH_MAX);
-    if ((U32)(cParams.strategy) > (U32)ZSTD_btopt2) return ERROR(compressionParameter_unsupported);
+    if ((U32)(cParams.strategy) > (U32)ZSTD_btultra) return ERROR(compressionParameter_unsupported);
     return 0;
 }
 
+/** ZSTD_clampCParams() :
+ *  make CParam values within valid range.
+ *  @return : valid CParams */
+static ZSTD_compressionParameters ZSTD_clampCParams(ZSTD_compressionParameters cParams)
+{
+#   define CLAMP(val,min,max) {      \
+        if (val<min) val=min;        \
+        else if (val>max) val=max;   \
+    }
+    CLAMP(cParams.windowLog, ZSTD_WINDOWLOG_MIN, ZSTD_WINDOWLOG_MAX);
+    CLAMP(cParams.chainLog, ZSTD_CHAINLOG_MIN, ZSTD_CHAINLOG_MAX);
+    CLAMP(cParams.hashLog, ZSTD_HASHLOG_MIN, ZSTD_HASHLOG_MAX);
+    CLAMP(cParams.searchLog, ZSTD_SEARCHLOG_MIN, ZSTD_SEARCHLOG_MAX);
+    CLAMP(cParams.searchLength, ZSTD_SEARCHLENGTH_MIN, ZSTD_SEARCHLENGTH_MAX);
+    CLAMP(cParams.targetLength, ZSTD_TARGETLENGTH_MIN, ZSTD_TARGETLENGTH_MAX);
+    if ((U32)(cParams.strategy) > (U32)ZSTD_btultra) cParams.strategy = ZSTD_btultra;
+    return cParams;
+}
 
 /** ZSTD_cycleLog() :
  *  condition for correct operation : hashLog > 1 */
@@ -196,14 +505,15 @@ static U32 ZSTD_cycleLog(U32 hashLog, ZSTD_strategy strat)
     return hashLog - btScale;
 }
 
-/** ZSTD_adjustCParams() :
+/** ZSTD_adjustCParams_internal() :
     optimize `cPar` for a given input (`srcSize` and `dictSize`).
     mostly downsizing to reduce memory consumption and initialization.
     Both `srcSize` and `dictSize` are optional (use 0 if unknown),
     but if both are 0, no optimization can be done.
     Note : cPar is considered validated at this stage. Use ZSTD_checkParams() to ensure that. */
-ZSTD_compressionParameters ZSTD_adjustCParams(ZSTD_compressionParameters cPar, unsigned long long srcSize, size_t dictSize)
+ZSTD_compressionParameters ZSTD_adjustCParams_internal(ZSTD_compressionParameters cPar, unsigned long long srcSize, size_t dictSize)
 {
+    assert(ZSTD_checkCParams(cPar)==0);
     if (srcSize+dictSize == 0) return cPar;   /* no size information available : no adjustment */
 
     /* resize params, to use less memory when necessary */
@@ -223,10 +533,16 @@ ZSTD_compressionParameters ZSTD_adjustCParams(ZSTD_compressionParameters cPar, u
     return cPar;
 }
 
+ZSTD_compressionParameters ZSTD_adjustCParams(ZSTD_compressionParameters cPar, unsigned long long srcSize, size_t dictSize)
+{
+    cPar = ZSTD_clampCParams(cPar);
+    return ZSTD_adjustCParams_internal(cPar, srcSize, dictSize);
+}
 
-size_t ZSTD_estimateCCtxSize(ZSTD_compressionParameters cParams)
+
+size_t ZSTD_estimateCCtxSize_advanced(ZSTD_compressionParameters cParams)
 {
-    size_t const blockSize = MIN(ZSTD_BLOCKSIZE_ABSOLUTEMAX, (size_t)1 << cParams.windowLog);
+    size_t const blockSize = MIN(ZSTD_BLOCKSIZE_MAX, (size_t)1 << cParams.windowLog);
     U32    const divider = (cParams.searchLength==3) ? 3 : 4;
     size_t const maxNbSeq = blockSize / divider;
     size_t const tokenSpace = blockSize + 11*maxNbSeq;
@@ -240,31 +556,64 @@ size_t ZSTD_estimateCCtxSize(ZSTD_compressionParameters cParams)
                               + entropyScratchSpace_size;
     size_t const tableSpace = (chainSize + hSize + h3Size) * sizeof(U32);
 
-    size_t const optSpace = ((MaxML+1) + (MaxLL+1) + (MaxOff+1) + (1<<Litbits))*sizeof(U32)
+    size_t const optBudget = ((MaxML+1) + (MaxLL+1) + (MaxOff+1) + (1<<Litbits))*sizeof(U32)
                           + (ZSTD_OPT_NUM+1)*(sizeof(ZSTD_match_t) + sizeof(ZSTD_optimal_t));
-    size_t const neededSpace = entropySpace + tableSpace + tokenSpace
-                             + (((cParams.strategy == ZSTD_btopt) || (cParams.strategy == ZSTD_btopt2)) ? optSpace : 0);
+    size_t const optSpace = ((cParams.strategy == ZSTD_btopt) || (cParams.strategy == ZSTD_btultra)) ? optBudget : 0;
+    size_t const neededSpace = entropySpace + tableSpace + tokenSpace + optSpace;
 
+    DEBUGLOG(5, "sizeof(ZSTD_CCtx) : %u", (U32)sizeof(ZSTD_CCtx));
+    DEBUGLOG(5, "estimate workSpace : %u", (U32)neededSpace);
     return sizeof(ZSTD_CCtx) + neededSpace;
 }
 
+size_t ZSTD_estimateCCtxSize(int compressionLevel)
+{
+    ZSTD_compressionParameters const cParams = ZSTD_getCParams(compressionLevel, 0, 0);
+    return ZSTD_estimateCCtxSize_advanced(cParams);
+}
 
-static U32 ZSTD_equivalentParams(ZSTD_parameters param1, ZSTD_parameters param2)
+size_t ZSTD_estimateCStreamSize_advanced(ZSTD_compressionParameters cParams)
 {
-    return (param1.cParams.hashLog  == param2.cParams.hashLog)
-         & (param1.cParams.chainLog == param2.cParams.chainLog)
-         & (param1.cParams.strategy == param2.cParams.strategy)
-         & ((param1.cParams.searchLength==3) == (param2.cParams.searchLength==3));
+    size_t const CCtxSize = ZSTD_estimateCCtxSize_advanced(cParams);
+    size_t const blockSize = MIN(ZSTD_BLOCKSIZE_MAX, (size_t)1 << cParams.windowLog);
+    size_t const inBuffSize = ((size_t)1 << cParams.windowLog) + blockSize;
+    size_t const outBuffSize = ZSTD_compressBound(blockSize) + 1;
+    size_t const streamingSize = inBuffSize + outBuffSize;
+
+    return CCtxSize + streamingSize;
+}
+
+size_t ZSTD_estimateCStreamSize(int compressionLevel) {
+    ZSTD_compressionParameters const cParams = ZSTD_getCParams(compressionLevel, 0, 0);
+    return ZSTD_estimateCStreamSize_advanced(cParams);
+}
+
+
+static U32 ZSTD_equivalentParams(ZSTD_compressionParameters cParams1,
+                                 ZSTD_compressionParameters cParams2)
+{
+    U32 bslog1 = MIN(cParams1.windowLog, ZSTD_BLOCKSIZELOG_MAX);
+    U32 bslog2 = MIN(cParams2.windowLog, ZSTD_BLOCKSIZELOG_MAX);
+    return (bslog1 == bslog2)   /* same block size */
+         & (cParams1.hashLog  == cParams2.hashLog)
+         & (cParams1.chainLog == cParams2.chainLog)
+         & (cParams1.strategy == cParams2.strategy)   /* opt parser space */
+         & ((cParams1.searchLength==3) == (cParams2.searchLength==3));  /* hashlog3 space */
 }
 
 /*! ZSTD_continueCCtx() :
-    reuse CCtx without reset (note : requires no dictionary) */
-static size_t ZSTD_continueCCtx(ZSTD_CCtx* cctx, ZSTD_parameters params, U64 frameContentSize)
+ *  reuse CCtx without reset (note : requires no dictionary) */
+static size_t ZSTD_continueCCtx(ZSTD_CCtx* cctx, ZSTD_parameters params, U64 pledgedSrcSize)
 {
     U32 const end = (U32)(cctx->nextSrc - cctx->base);
-    cctx->params = params;
-    cctx->frameContentSize = frameContentSize;
+    DEBUGLOG(5, "continue mode");
+    cctx->appliedParams = params;
+    cctx->pledgedSrcSizePlusOne = pledgedSrcSize+1;
     cctx->consumedSrcSize = 0;
+    if (pledgedSrcSize == ZSTD_CONTENTSIZE_UNKNOWN)
+        cctx->appliedParams.fParams.contentSizeFlag = 0;
+    DEBUGLOG(5, "pledged content size : %u ; flag : %u",
+        (U32)pledgedSrcSize, cctx->appliedParams.fParams.contentSizeFlag);
     cctx->lowLimit = end;
     cctx->dictLimit = end;
     cctx->nextToUpdate = end+1;
@@ -277,30 +626,39 @@ static size_t ZSTD_continueCCtx(ZSTD_CCtx* cctx, ZSTD_parameters params, U64 fra
     return 0;
 }
 
-typedef enum { ZSTDcrp_continue, ZSTDcrp_noMemset, ZSTDcrp_fullReset } ZSTD_compResetPolicy_e;
+typedef enum { ZSTDcrp_continue, ZSTDcrp_noMemset } ZSTD_compResetPolicy_e;
+typedef enum { ZSTDb_not_buffered, ZSTDb_buffered } ZSTD_buffered_policy_e;
 
 /*! ZSTD_resetCCtx_internal() :
-    note : `params` must be validated */
-static size_t ZSTD_resetCCtx_internal (ZSTD_CCtx* zc,
-                                       ZSTD_parameters params, U64 frameContentSize,
-                                       ZSTD_compResetPolicy_e const crp)
+    note : `params` are assumed fully validated at this stage */
+static size_t ZSTD_resetCCtx_internal(ZSTD_CCtx* zc,
+                                      ZSTD_parameters params, U64 pledgedSrcSize,
+                                      ZSTD_compResetPolicy_e const crp,
+                                      ZSTD_buffered_policy_e const zbuff)
 {
-    if (crp == ZSTDcrp_continue)
-        if (ZSTD_equivalentParams(params, zc->params)) {
+    assert(!ZSTD_isError(ZSTD_checkCParams(params.cParams)));
+
+    if (crp == ZSTDcrp_continue) {
+        if (ZSTD_equivalentParams(params.cParams, zc->appliedParams.cParams)) {
+            DEBUGLOG(5, "ZSTD_equivalentParams()==1");
             zc->fseCTables_ready = 0;
             zc->hufCTable_repeatMode = HUF_repeat_none;
-            return ZSTD_continueCCtx(zc, params, frameContentSize);
-        }
+            return ZSTD_continueCCtx(zc, params, pledgedSrcSize);
+    }   }
 
-    {   size_t const blockSize = MIN(ZSTD_BLOCKSIZE_ABSOLUTEMAX, (size_t)1 << params.cParams.windowLog);
+    {   size_t const blockSize = MIN(ZSTD_BLOCKSIZE_MAX, (size_t)1 << params.cParams.windowLog);
         U32    const divider = (params.cParams.searchLength==3) ? 3 : 4;
         size_t const maxNbSeq = blockSize / divider;
         size_t const tokenSpace = blockSize + 11*maxNbSeq;
-        size_t const chainSize = (params.cParams.strategy == ZSTD_fast) ? 0 : (1 << params.cParams.chainLog);
+        size_t const chainSize = (params.cParams.strategy == ZSTD_fast) ?
+                                0 : (1 << params.cParams.chainLog);
         size_t const hSize = ((size_t)1) << params.cParams.hashLog;
-        U32    const hashLog3 = (params.cParams.searchLength>3) ? 0 : MIN(ZSTD_HASHLOG3_MAX, params.cParams.windowLog);
+        U32    const hashLog3 = (params.cParams.searchLength>3) ?
+                                0 : MIN(ZSTD_HASHLOG3_MAX, params.cParams.windowLog);
         size_t const h3Size = ((size_t)1) << hashLog3;
         size_t const tableSpace = (chainSize + hSize + h3Size) * sizeof(U32);
+        size_t const buffOutSize = (zbuff==ZSTDb_buffered) ? ZSTD_compressBound(blockSize)+1 : 0;
+        size_t const buffInSize = (zbuff==ZSTDb_buffered) ? ((size_t)1 << params.cParams.windowLog) + blockSize : 0;
         void* ptr;
 
         /* Check if workSpace is large enough, alloc a new one if needed */
@@ -309,9 +667,20 @@ static size_t ZSTD_resetCCtx_internal (ZSTD_CCtx* zc,
                                   + entropyScratchSpace_size;
             size_t const optPotentialSpace = ((MaxML+1) + (MaxLL+1) + (MaxOff+1) + (1<<Litbits)) * sizeof(U32)
                                   + (ZSTD_OPT_NUM+1) * (sizeof(ZSTD_match_t)+sizeof(ZSTD_optimal_t));
-            size_t const optSpace = ((params.cParams.strategy == ZSTD_btopt) || (params.cParams.strategy == ZSTD_btopt2)) ? optPotentialSpace : 0;
-            size_t const neededSpace = entropySpace + optSpace + tableSpace + tokenSpace;
-            if (zc->workSpaceSize < neededSpace) {
+            size_t const optSpace = ( (params.cParams.strategy == ZSTD_btopt)
+                                    || (params.cParams.strategy == ZSTD_btultra)) ?
+                                    optPotentialSpace : 0;
+            size_t const bufferSpace = buffInSize + buffOutSize;
+            size_t const neededSpace = entropySpace + optSpace + tableSpace
+                                     + tokenSpace + bufferSpace;
+
+            if (zc->workSpaceSize < neededSpace) {  /* too small : resize /*/
+                DEBUGLOG(5, "Need to update workSpaceSize from %uK to %uK \n",
+                            (unsigned)zc->workSpaceSize>>10,
+                            (unsigned)neededSpace>>10);
+                /* static cctx : no resize, error out */
+                if (zc->staticSize) return ERROR(memory_allocation);
+
                 zc->workSpaceSize = 0;
                 ZSTD_free(zc->workSpace, zc->customMem);
                 zc->workSpace = ZSTD_malloc(neededSpace, zc->customMem);
@@ -333,10 +702,14 @@ static size_t ZSTD_resetCCtx_internal (ZSTD_CCtx* zc,
         }   }
 
         /* init params */
-        zc->params = params;
-        zc->blockSize = blockSize;
-        zc->frameContentSize = frameContentSize;
+        zc->appliedParams = params;
+        zc->pledgedSrcSizePlusOne = pledgedSrcSize+1;
         zc->consumedSrcSize = 0;
+        if (pledgedSrcSize == ZSTD_CONTENTSIZE_UNKNOWN)
+            zc->appliedParams.fParams.contentSizeFlag = 0;
+        DEBUGLOG(5, "pledged content size : %u ; flag : %u",
+            (U32)pledgedSrcSize, zc->appliedParams.fParams.contentSizeFlag);
+        zc->blockSize = blockSize;
 
         XXH64_reset(&zc->xxhState, 0);
         zc->stage = ZSTDcs_init;
@@ -363,7 +736,8 @@ static size_t ZSTD_resetCCtx_internal (ZSTD_CCtx* zc,
         ptr = (char*)zc->entropyScratchSpace + entropyScratchSpace_size;
 
         /* opt parser space */
-        if ((params.cParams.strategy == ZSTD_btopt) || (params.cParams.strategy == ZSTD_btopt2)) {
+        if ((params.cParams.strategy == ZSTD_btopt) || (params.cParams.strategy == ZSTD_btultra)) {
+            DEBUGLOG(5, "reserving optimal parser space");
             assert(((size_t)ptr & 3) == 0);  /* ensure ptr is properly aligned */
             zc->seqStore.litFreq = (U32*)ptr;
             zc->seqStore.litLengthFreq = zc->seqStore.litFreq + (1<<Litbits);
@@ -391,6 +765,13 @@ static size_t ZSTD_resetCCtx_internal (ZSTD_CCtx* zc,
         zc->seqStore.mlCode = zc->seqStore.llCode + maxNbSeq;
         zc->seqStore.ofCode = zc->seqStore.mlCode + maxNbSeq;
         zc->seqStore.litStart = zc->seqStore.ofCode + maxNbSeq;
+        ptr = zc->seqStore.litStart + blockSize;
+
+        /* buffers */
+        zc->inBuffSize = buffInSize;
+        zc->inBuff = (char*)ptr;
+        zc->outBuffSize = buffOutSize;
+        zc->outBuff = zc->inBuff + buffInSize;
 
         return 0;
     }
@@ -411,21 +792,25 @@ void ZSTD_invalidateRepCodes(ZSTD_CCtx* cctx) {
  *  Only works during stage ZSTDcs_init (i.e. after creation, but before first call to ZSTD_compressContinue()).
  *  pledgedSrcSize=0 means "empty" if fParams.contentSizeFlag=1
  *  @return : 0, or an error code */
-size_t ZSTD_copyCCtx_internal(ZSTD_CCtx* dstCCtx, const ZSTD_CCtx* srcCCtx,
-                              ZSTD_frameParameters fParams, unsigned long long pledgedSrcSize)
+static size_t ZSTD_copyCCtx_internal(ZSTD_CCtx* dstCCtx,
+                            const ZSTD_CCtx* srcCCtx,
+                            ZSTD_frameParameters fParams,
+                            unsigned long long pledgedSrcSize,
+                            ZSTD_buffered_policy_e zbuff)
 {
+    DEBUGLOG(5, "ZSTD_copyCCtx_internal");
     if (srcCCtx->stage!=ZSTDcs_init) return ERROR(stage_wrong);
 
     memcpy(&dstCCtx->customMem, &srcCCtx->customMem, sizeof(ZSTD_customMem));
-    {   ZSTD_parameters params = srcCCtx->params;
+    {   ZSTD_parameters params = srcCCtx->appliedParams;
         params.fParams = fParams;
-        DEBUGLOG(5, "ZSTD_resetCCtx_internal : dictIDFlag : %u \n", !fParams.noDictIDFlag);
-        ZSTD_resetCCtx_internal(dstCCtx, params, pledgedSrcSize, ZSTDcrp_noMemset);
+        ZSTD_resetCCtx_internal(dstCCtx, params, pledgedSrcSize,
+                                ZSTDcrp_noMemset, zbuff);
     }
 
     /* copy tables */
-    {   size_t const chainSize = (srcCCtx->params.cParams.strategy == ZSTD_fast) ? 0 : (1 << srcCCtx->params.cParams.chainLog);
-        size_t const hSize =  (size_t)1 << srcCCtx->params.cParams.hashLog;
+    {   size_t const chainSize = (srcCCtx->appliedParams.cParams.strategy == ZSTD_fast) ? 0 : (1 << srcCCtx->appliedParams.cParams.chainLog);
+        size_t const hSize =  (size_t)1 << srcCCtx->appliedParams.cParams.hashLog;
         size_t const h3Size = (size_t)1 << srcCCtx->hashLog3;
         size_t const tableSpace = (chainSize + hSize + h3Size) * sizeof(U32);
         assert((U32*)dstCCtx->chainTable == (U32*)dstCCtx->hashTable + hSize);  /* chainTable must follow hashTable */
@@ -467,9 +852,11 @@ size_t ZSTD_copyCCtx_internal(ZSTD_CCtx* dstCCtx, const ZSTD_CCtx* srcCCtx,
 size_t ZSTD_copyCCtx(ZSTD_CCtx* dstCCtx, const ZSTD_CCtx* srcCCtx, unsigned long long pledgedSrcSize)
 {
     ZSTD_frameParameters fParams = { 1 /*content*/, 0 /*checksum*/, 0 /*noDictID*/ };
+    ZSTD_buffered_policy_e const zbuff = (ZSTD_buffered_policy_e)(srcCCtx->inBuffSize>0);
+    ZSTD_STATIC_ASSERT((U32)ZSTDb_buffered==1);
     fParams.contentSizeFlag = pledgedSrcSize>0;
 
-    return ZSTD_copyCCtx_internal(dstCCtx, srcCCtx, fParams, pledgedSrcSize);
+    return ZSTD_copyCCtx_internal(dstCCtx, srcCCtx, fParams, pledgedSrcSize, zbuff);
 }
 
 
@@ -488,10 +875,10 @@ static void ZSTD_reduceTable (U32* const table, U32 const size, U32 const reduce
 *   rescale all indexes to avoid future overflow (indexes are U32) */
 static void ZSTD_reduceIndex (ZSTD_CCtx* zc, const U32 reducerValue)
 {
-    { U32 const hSize = 1 << zc->params.cParams.hashLog;
+    { U32 const hSize = 1 << zc->appliedParams.cParams.hashLog;
       ZSTD_reduceTable(zc->hashTable, hSize, reducerValue); }
 
-    { U32 const chainSize = (zc->params.cParams.strategy == ZSTD_fast) ? 0 : (1 << zc->params.cParams.chainLog);
+    { U32 const chainSize = (zc->appliedParams.cParams.strategy == ZSTD_fast) ? 0 : (1 << zc->appliedParams.cParams.chainLog);
       ZSTD_reduceTable(zc->chainTable, chainSize, reducerValue); }
 
     { U32 const h3Size = (zc->hashLog3) ? 1 << zc->hashLog3 : 0;
@@ -529,10 +916,11 @@ static size_t ZSTD_noCompressLiterals (void* dst, size_t dstCapacity, const void
         case 2: /* 2 - 2 - 12 */
             MEM_writeLE16(ostart, (U16)((U32)set_basic + (1<<2) + (srcSize<<4)));
             break;
-        default:   /*note : should not be necessary : flSize is within {1,2,3} */
         case 3: /* 2 - 2 - 20 */
             MEM_writeLE32(ostart, (U32)((U32)set_basic + (3<<2) + (srcSize<<4)));
             break;
+        default:   /* not necessary : flSize is {1,2,3} */
+            assert(0);
     }
 
     memcpy(ostart + flSize, src, srcSize);
@@ -554,10 +942,11 @@ static size_t ZSTD_compressRleLiteralsBlock (void* dst, size_t dstCapacity, cons
         case 2: /* 2 - 2 - 12 */
             MEM_writeLE16(ostart, (U16)((U32)set_rle + (1<<2) + (srcSize<<4)));
             break;
-        default:   /*note : should not be necessary : flSize is necessarily within {1,2,3} */
         case 3: /* 2 - 2 - 20 */
             MEM_writeLE32(ostart, (U32)((U32)set_rle + (3<<2) + (srcSize<<4)));
             break;
+        default:   /* not necessary : flSize is {1,2,3} */
+            assert(0);
     }
 
     ostart[flSize] = *(const BYTE*)src;
@@ -587,7 +976,7 @@ static size_t ZSTD_compressLiterals (ZSTD_CCtx* zc,
 
     if (dstCapacity < lhSize+1) return ERROR(dstSize_tooSmall);   /* not enough space for compression */
     {   HUF_repeat repeat = zc->hufCTable_repeatMode;
-        int const preferRepeat = zc->params.cParams.strategy < ZSTD_lazy ? srcSize <= 1024 : 0;
+        int const preferRepeat = zc->appliedParams.cParams.strategy < ZSTD_lazy ? srcSize <= 1024 : 0;
         if (repeat == HUF_repeat_valid && lhSize == 3) singleStream = 1;
         cLitSize = singleStream ? HUF_compress1X_repeat(ostart+lhSize, dstCapacity-lhSize, src, srcSize, 255, 11,
                                       zc->entropyScratchSpace, entropyScratchSpace_size, zc->hufCTable, &repeat, preferRepeat)
@@ -619,13 +1008,14 @@ static size_t ZSTD_compressLiterals (ZSTD_CCtx* zc,
             MEM_writeLE32(ostart, lhc);
             break;
         }
-    default:   /* should not be necessary, lhSize is only {3,4,5} */
     case 5: /* 2 - 2 - 18 - 18 */
         {   U32 const lhc = hType + (3 << 2) + ((U32)srcSize<<4) + ((U32)cLitSize<<22);
             MEM_writeLE32(ostart, lhc);
             ostart[4] = (BYTE)(cLitSize >> 10);
             break;
         }
+    default:   /* not possible : lhSize is {3,4,5} */
+        assert(0);
     }
     return lhSize+cLitSize;
 }
@@ -676,7 +1066,7 @@ MEM_STATIC size_t ZSTD_compressSequences (ZSTD_CCtx* zc,
                               void* dst, size_t dstCapacity,
                               size_t srcSize)
 {
-    const int longOffsets = zc->params.cParams.windowLog > STREAM_ACCUMULATOR_MIN;
+    const int longOffsets = zc->appliedParams.cParams.windowLog > STREAM_ACCUMULATOR_MIN;
     const seqStore_t* seqStorePtr = &(zc->seqStore);
     U32 count[MaxSeq+1];
     S16 norm[MaxSeq+1];
@@ -881,12 +1271,6 @@ _check_compressibility:
     return op - ostart;
 }
 
-#if 0 /* for debug */
-#  define STORESEQ_DEBUG
-#include <stdio.h>   /* fprintf */
-U32 g_startDebug = 0;
-const BYTE* g_start = NULL;
-#endif
 
 /*! ZSTD_storeSeq() :
     Store a sequence (literal length, literals, offset code and match length code) into seqStore_t.
@@ -895,16 +1279,16 @@ const BYTE* g_start = NULL;
 */
 MEM_STATIC void ZSTD_storeSeq(seqStore_t* seqStorePtr, size_t litLength, const void* literals, U32 offsetCode, size_t matchCode)
 {
-#ifdef STORESEQ_DEBUG
-    if (g_startDebug) {
-        const U32 pos = (U32)((const BYTE*)literals - g_start);
-        if (g_start==NULL) g_start = (const BYTE*)literals;
-        if ((pos > 1895000) && (pos < 1895300))
-            DEBUGLOG(5, "Cpos %6u :%5u literals & match %3u bytes at distance %6u \n",
-                   pos, (U32)litLength, (U32)matchCode+MINMATCH, (U32)offsetCode);
-    }
+#if defined(ZSTD_DEBUG) && (ZSTD_DEBUG >= 6)
+    static const BYTE* g_start = NULL;
+    U32 const pos = (U32)((const BYTE*)literals - g_start);
+    if (g_start==NULL) g_start = (const BYTE*)literals;
+    if ((pos > 0) && (pos < 1000000000))
+        DEBUGLOG(6, "Cpos %6u :%5u literals & match %3u bytes at distance %6u",
+               pos, (U32)litLength, (U32)matchCode+MINMATCH, (U32)offsetCode);
 #endif
     /* copy Literals */
+    assert(seqStorePtr->lit + litLength <= seqStorePtr->litStart + 128 KB);
     ZSTD_wildcopy(seqStorePtr->lit, literals, litLength);
     seqStorePtr->lit += litLength;
 
@@ -1078,7 +1462,7 @@ static size_t ZSTD_hashPtr(const void* p, U32 hBits, U32 mls)
 static void ZSTD_fillHashTable (ZSTD_CCtx* zc, const void* end, const U32 mls)
 {
     U32* const hashTable = zc->hashTable;
-    U32  const hBits = zc->params.cParams.hashLog;
+    U32  const hBits = zc->appliedParams.cParams.hashLog;
     const BYTE* const base = zc->base;
     const BYTE* ip = base + zc->nextToUpdate;
     const BYTE* const iend = ((const BYTE*)end) - HASH_READ_SIZE;
@@ -1097,7 +1481,7 @@ void ZSTD_compressBlock_fast_generic(ZSTD_CCtx* cctx,
                                const U32 mls)
 {
     U32* const hashTable = cctx->hashTable;
-    U32  const hBits = cctx->params.cParams.hashLog;
+    U32  const hBits = cctx->appliedParams.cParams.hashLog;
     seqStore_t* seqStorePtr = &(cctx->seqStore);
     const BYTE* const base = cctx->base;
     const BYTE* const istart = (const BYTE*)src;
@@ -1182,7 +1566,7 @@ void ZSTD_compressBlock_fast_generic(ZSTD_CCtx* cctx,
 static void ZSTD_compressBlock_fast(ZSTD_CCtx* ctx,
                        const void* src, size_t srcSize)
 {
-    const U32 mls = ctx->params.cParams.searchLength;
+    const U32 mls = ctx->appliedParams.cParams.searchLength;
     switch(mls)
     {
     default: /* includes case 3 */
@@ -1203,7 +1587,7 @@ static void ZSTD_compressBlock_fast_extDict_generic(ZSTD_CCtx* ctx,
                                  const U32 mls)
 {
     U32* hashTable = ctx->hashTable;
-    const U32 hBits = ctx->params.cParams.hashLog;
+    const U32 hBits = ctx->appliedParams.cParams.hashLog;
     seqStore_t* seqStorePtr = &(ctx->seqStore);
     const BYTE* const base = ctx->base;
     const BYTE* const dictBase = ctx->dictBase;
@@ -1296,7 +1680,7 @@ static void ZSTD_compressBlock_fast_extDict_generic(ZSTD_CCtx* ctx,
 static void ZSTD_compressBlock_fast_extDict(ZSTD_CCtx* ctx,
                          const void* src, size_t srcSize)
 {
-    U32 const mls = ctx->params.cParams.searchLength;
+    U32 const mls = ctx->appliedParams.cParams.searchLength;
     switch(mls)
     {
     default: /* includes case 3 */
@@ -1318,9 +1702,9 @@ static void ZSTD_compressBlock_fast_extDict(ZSTD_CCtx* ctx,
 static void ZSTD_fillDoubleHashTable (ZSTD_CCtx* cctx, const void* end, const U32 mls)
 {
     U32* const hashLarge = cctx->hashTable;
-    U32  const hBitsL = cctx->params.cParams.hashLog;
+    U32  const hBitsL = cctx->appliedParams.cParams.hashLog;
     U32* const hashSmall = cctx->chainTable;
-    U32  const hBitsS = cctx->params.cParams.chainLog;
+    U32  const hBitsS = cctx->appliedParams.cParams.chainLog;
     const BYTE* const base = cctx->base;
     const BYTE* ip = base + cctx->nextToUpdate;
     const BYTE* const iend = ((const BYTE*)end) - HASH_READ_SIZE;
@@ -1340,9 +1724,9 @@ void ZSTD_compressBlock_doubleFast_generic(ZSTD_CCtx* cctx,
                                  const U32 mls)
 {
     U32* const hashLong = cctx->hashTable;
-    const U32 hBitsL = cctx->params.cParams.hashLog;
+    const U32 hBitsL = cctx->appliedParams.cParams.hashLog;
     U32* const hashSmall = cctx->chainTable;
-    const U32 hBitsS = cctx->params.cParams.chainLog;
+    const U32 hBitsS = cctx->appliedParams.cParams.chainLog;
     seqStore_t* seqStorePtr = &(cctx->seqStore);
     const BYTE* const base = cctx->base;
     const BYTE* const istart = (const BYTE*)src;
@@ -1452,7 +1836,7 @@ void ZSTD_compressBlock_doubleFast_generic(ZSTD_CCtx* cctx,
 
 static void ZSTD_compressBlock_doubleFast(ZSTD_CCtx* ctx, const void* src, size_t srcSize)
 {
-    const U32 mls = ctx->params.cParams.searchLength;
+    const U32 mls = ctx->appliedParams.cParams.searchLength;
     switch(mls)
     {
     default: /* includes case 3 */
@@ -1473,9 +1857,9 @@ static void ZSTD_compressBlock_doubleFast_extDict_generic(ZSTD_CCtx* ctx,
                                  const U32 mls)
 {
     U32* const hashLong = ctx->hashTable;
-    U32  const hBitsL = ctx->params.cParams.hashLog;
+    U32  const hBitsL = ctx->appliedParams.cParams.hashLog;
     U32* const hashSmall = ctx->chainTable;
-    U32  const hBitsS = ctx->params.cParams.chainLog;
+    U32  const hBitsS = ctx->appliedParams.cParams.chainLog;
     seqStore_t* seqStorePtr = &(ctx->seqStore);
     const BYTE* const base = ctx->base;
     const BYTE* const dictBase = ctx->dictBase;
@@ -1602,7 +1986,7 @@ static void ZSTD_compressBlock_doubleFast_extDict_generic(ZSTD_CCtx* ctx,
 static void ZSTD_compressBlock_doubleFast_extDict(ZSTD_CCtx* ctx,
                          const void* src, size_t srcSize)
 {
-    U32 const mls = ctx->params.cParams.searchLength;
+    U32 const mls = ctx->appliedParams.cParams.searchLength;
     switch(mls)
     {
     default: /* includes case 3 */
@@ -1628,10 +2012,10 @@ static U32 ZSTD_insertBt1(ZSTD_CCtx* zc, const BYTE* const ip, const U32 mls, co
                           U32 extDict)
 {
     U32*   const hashTable = zc->hashTable;
-    U32    const hashLog = zc->params.cParams.hashLog;
+    U32    const hashLog = zc->appliedParams.cParams.hashLog;
     size_t const h  = ZSTD_hashPtr(ip, hashLog, mls);
     U32*   const bt = zc->chainTable;
-    U32    const btLog  = zc->params.cParams.chainLog - 1;
+    U32    const btLog  = zc->appliedParams.cParams.chainLog - 1;
     U32    const btMask = (1 << btLog) - 1;
     U32 matchIndex = hashTable[h];
     size_t commonLengthSmaller=0, commonLengthLarger=0;
@@ -1733,10 +2117,10 @@ static size_t ZSTD_insertBtAndFindBestMatch (
                         U32 extDict)
 {
     U32*   const hashTable = zc->hashTable;
-    U32    const hashLog = zc->params.cParams.hashLog;
+    U32    const hashLog = zc->appliedParams.cParams.hashLog;
     size_t const h  = ZSTD_hashPtr(ip, hashLog, mls);
     U32*   const bt = zc->chainTable;
-    U32    const btLog  = zc->params.cParams.chainLog - 1;
+    U32    const btLog  = zc->appliedParams.cParams.chainLog - 1;
     U32    const btMask = (1 << btLog) - 1;
     U32 matchIndex  = hashTable[h];
     size_t commonLengthSmaller=0, commonLengthLarger=0;
@@ -1896,9 +2280,9 @@ FORCE_INLINE
 U32 ZSTD_insertAndFindFirstIndex (ZSTD_CCtx* zc, const BYTE* ip, U32 mls)
 {
     U32* const hashTable  = zc->hashTable;
-    const U32 hashLog = zc->params.cParams.hashLog;
+    const U32 hashLog = zc->appliedParams.cParams.hashLog;
     U32* const chainTable = zc->chainTable;
-    const U32 chainMask = (1 << zc->params.cParams.chainLog) - 1;
+    const U32 chainMask = (1 << zc->appliedParams.cParams.chainLog) - 1;
     const BYTE* const base = zc->base;
     const U32 target = (U32)(ip - base);
     U32 idx = zc->nextToUpdate;
@@ -1915,8 +2299,8 @@ U32 ZSTD_insertAndFindFirstIndex (ZSTD_CCtx* zc, const BYTE* ip, U32 mls)
 }
 
 
-
-FORCE_INLINE /* inlining is important to hardwire a hot branch (template emulation) */
+/* inlining is important to hardwire a hot branch (template emulation) */
+FORCE_INLINE
 size_t ZSTD_HcFindBestMatch_generic (
                         ZSTD_CCtx* zc,   /* Index table will be updated */
                         const BYTE* const ip, const BYTE* const iLimit,
@@ -1924,7 +2308,7 @@ size_t ZSTD_HcFindBestMatch_generic (
                         const U32 maxNbAttempts, const U32 mls, const U32 extDict)
 {
     U32* const chainTable = zc->chainTable;
-    const U32 chainSize = (1 << zc->params.cParams.chainLog);
+    const U32 chainSize = (1 << zc->appliedParams.cParams.chainLog);
     const U32 chainMask = chainSize-1;
     const BYTE* const base = zc->base;
     const BYTE* const dictBase = zc->dictBase;
@@ -2018,8 +2402,8 @@ void ZSTD_compressBlock_lazy_generic(ZSTD_CCtx* ctx,
     const BYTE* const ilimit = iend - 8;
     const BYTE* const base = ctx->base + ctx->dictLimit;
 
-    U32 const maxSearches = 1 << ctx->params.cParams.searchLog;
-    U32 const mls = ctx->params.cParams.searchLength;
+    U32 const maxSearches = 1 << ctx->appliedParams.cParams.searchLog;
+    U32 const mls = ctx->appliedParams.cParams.searchLength;
 
     typedef size_t (*searchMax_f)(ZSTD_CCtx* zc, const BYTE* ip, const BYTE* iLimit,
                         size_t* offsetPtr,
@@ -2101,15 +2485,19 @@ void ZSTD_compressBlock_lazy_generic(ZSTD_CCtx* ctx,
             break;  /* nothing found : store previous solution */
         }
 
+        /* NOTE:
+         * start[-offset+ZSTD_REP_MOVE-1] is undefined behavior.
+         * (-offset+ZSTD_REP_MOVE-1) is unsigned, and is added to start, which
+         * overflows the pointer, which is undefined behavior.
+         */
         /* catch up */
         if (offset) {
             while ( (start > anchor)
                  && (start > base+offset-ZSTD_REP_MOVE)
-                 && (start[-1] == start[-1-offset+ZSTD_REP_MOVE]) )  /* only search for offset within prefix */
+                 && (start[-1] == (start-offset+ZSTD_REP_MOVE)[-1]) )  /* only search for offset within prefix */
                 { start--; matchLength++; }
             offset_2 = offset_1; offset_1 = (U32)(offset - ZSTD_REP_MOVE);
         }
-
         /* store sequence */
 _storeSequence:
         {   size_t const litLength = start - anchor;
@@ -2182,8 +2570,8 @@ void ZSTD_compressBlock_lazy_extDict_generic(ZSTD_CCtx* ctx,
     const BYTE* const dictEnd  = dictBase + dictLimit;
     const BYTE* const dictStart  = dictBase + ctx->lowLimit;
 
-    const U32 maxSearches = 1 << ctx->params.cParams.searchLog;
-    const U32 mls = ctx->params.cParams.searchLength;
+    const U32 maxSearches = 1 << ctx->appliedParams.cParams.searchLog;
+    const U32 mls = ctx->appliedParams.cParams.searchLength;
 
     typedef size_t (*searchMax_f)(ZSTD_CCtx* zc, const BYTE* ip, const BYTE* iLimit,
                         size_t* offsetPtr,
@@ -2370,7 +2758,7 @@ static void ZSTD_compressBlock_btopt(ZSTD_CCtx* ctx, const void* src, size_t src
 #endif
 }
 
-static void ZSTD_compressBlock_btopt2(ZSTD_CCtx* ctx, const void* src, size_t srcSize)
+static void ZSTD_compressBlock_btultra(ZSTD_CCtx* ctx, const void* src, size_t srcSize)
 {
 #ifdef ZSTD_OPT_H_91842398743
     ZSTD_compressBlock_opt_generic(ctx, src, srcSize, 1);
@@ -2390,7 +2778,7 @@ static void ZSTD_compressBlock_btopt_extDict(ZSTD_CCtx* ctx, const void* src, si
 #endif
 }
 
-static void ZSTD_compressBlock_btopt2_extDict(ZSTD_CCtx* ctx, const void* src, size_t srcSize)
+static void ZSTD_compressBlock_btultra_extDict(ZSTD_CCtx* ctx, const void* src, size_t srcSize)
 {
 #ifdef ZSTD_OPT_H_91842398743
     ZSTD_compressBlock_opt_extDict_generic(ctx, src, srcSize, 1);
@@ -2401,26 +2789,32 @@ static void ZSTD_compressBlock_btopt2_extDict(ZSTD_CCtx* ctx, const void* src, s
 }
 
 
+/* ZSTD_selectBlockCompressor() :
+ * assumption : strat is a valid strategy */
 typedef void (*ZSTD_blockCompressor) (ZSTD_CCtx* ctx, const void* src, size_t srcSize);
-
 static ZSTD_blockCompressor ZSTD_selectBlockCompressor(ZSTD_strategy strat, int extDict)
 {
-    static const ZSTD_blockCompressor blockCompressor[2][8] = {
-        { ZSTD_compressBlock_fast, ZSTD_compressBlock_doubleFast, ZSTD_compressBlock_greedy,
+    static const ZSTD_blockCompressor blockCompressor[2][(unsigned)ZSTD_btultra+1] = {
+        { ZSTD_compressBlock_fast  /* default for 0 */,
+          ZSTD_compressBlock_fast, ZSTD_compressBlock_doubleFast, ZSTD_compressBlock_greedy,
           ZSTD_compressBlock_lazy, ZSTD_compressBlock_lazy2, ZSTD_compressBlock_btlazy2,
-          ZSTD_compressBlock_btopt, ZSTD_compressBlock_btopt2 },
-        { ZSTD_compressBlock_fast_extDict, ZSTD_compressBlock_doubleFast_extDict, ZSTD_compressBlock_greedy_extDict,
+          ZSTD_compressBlock_btopt, ZSTD_compressBlock_btultra },
+        { ZSTD_compressBlock_fast_extDict  /* default for 0 */,
+          ZSTD_compressBlock_fast_extDict, ZSTD_compressBlock_doubleFast_extDict, ZSTD_compressBlock_greedy_extDict,
           ZSTD_compressBlock_lazy_extDict,ZSTD_compressBlock_lazy2_extDict, ZSTD_compressBlock_btlazy2_extDict,
-          ZSTD_compressBlock_btopt_extDict, ZSTD_compressBlock_btopt2_extDict }
+          ZSTD_compressBlock_btopt_extDict, ZSTD_compressBlock_btultra_extDict }
     };
+    ZSTD_STATIC_ASSERT((unsigned)ZSTD_fast == 1);
+    assert((U32)strat >= (U32)ZSTD_fast);
+    assert((U32)strat <= (U32)ZSTD_btultra);
 
-    return blockCompressor[extDict][(U32)strat];
+    return blockCompressor[extDict!=0][(U32)strat];
 }
 
 
 static size_t ZSTD_compressBlock_internal(ZSTD_CCtx* zc, void* dst, size_t dstCapacity, const void* src, size_t srcSize)
 {
-    ZSTD_blockCompressor const blockCompressor = ZSTD_selectBlockCompressor(zc->params.cParams.strategy, zc->lowLimit < zc->dictLimit);
+    ZSTD_blockCompressor const blockCompressor = ZSTD_selectBlockCompressor(zc->appliedParams.cParams.strategy, zc->lowLimit < zc->dictLimit);
     const BYTE* const base = zc->base;
     const BYTE* const istart = (const BYTE*)src;
     const U32 current = (U32)(istart-base);
@@ -2433,14 +2827,14 @@ static size_t ZSTD_compressBlock_internal(ZSTD_CCtx* zc, void* dst, size_t dstCa
 }
 
 
-/*! ZSTD_compress_generic() :
+/*! ZSTD_compress_frameChunk() :
 *   Compress a chunk of data into one or multiple blocks.
 *   All blocks will be terminated, all input will be consumed.
 *   Function will issue an error if there is not enough `dstCapacity` to hold the compressed content.
 *   Frame is supposed already started (header already produced)
 *   @return : compressed size, or an error code
 */
-static size_t ZSTD_compress_generic (ZSTD_CCtx* cctx,
+static size_t ZSTD_compress_frameChunk (ZSTD_CCtx* cctx,
                                      void* dst, size_t dstCapacity,
                                const void* src, size_t srcSize,
                                      U32 lastFrameChunk)
@@ -2450,9 +2844,9 @@ static size_t ZSTD_compress_generic (ZSTD_CCtx* cctx,
     const BYTE* ip = (const BYTE*)src;
     BYTE* const ostart = (BYTE*)dst;
     BYTE* op = ostart;
-    U32 const maxDist = 1 << cctx->params.cParams.windowLog;
+    U32 const maxDist = 1 << cctx->appliedParams.cParams.windowLog;
 
-    if (cctx->params.fParams.checksumFlag && srcSize)
+    if (cctx->appliedParams.fParams.checksumFlag && srcSize)
         XXH64_update(&cctx->xxhState, src, srcSize);
 
     while (remaining) {
@@ -2465,9 +2859,9 @@ static size_t ZSTD_compress_generic (ZSTD_CCtx* cctx,
 
         /* preemptive overflow correction */
         if (cctx->lowLimit > (3U<<29)) {
-            U32 const cycleMask = (1 << ZSTD_cycleLog(cctx->params.cParams.hashLog, cctx->params.cParams.strategy)) - 1;
+            U32 const cycleMask = (1 << ZSTD_cycleLog(cctx->appliedParams.cParams.hashLog, cctx->appliedParams.cParams.strategy)) - 1;
             U32 const current = (U32)(ip - cctx->base);
-            U32 const newCurrent = (current & cycleMask) + (1 << cctx->params.cParams.windowLog);
+            U32 const newCurrent = (current & cycleMask) + (1 << cctx->appliedParams.cParams.windowLog);
             U32 const correction = current - newCurrent;
             ZSTD_STATIC_ASSERT(ZSTD_WINDOWLOG_MAX_64 <= 30);
             ZSTD_reduceIndex(cctx, correction);
@@ -2522,22 +2916,20 @@ static size_t ZSTD_writeFrameHeader(void* dst, size_t dstCapacity,
     U32   const singleSegment = params.fParams.contentSizeFlag && (windowSize >= pledgedSrcSize);
     BYTE  const windowLogByte = (BYTE)((params.cParams.windowLog - ZSTD_WINDOWLOG_ABSOLUTEMIN) << 3);
     U32   const fcsCode = params.fParams.contentSizeFlag ?
-                     (pledgedSrcSize>=256) + (pledgedSrcSize>=65536+256) + (pledgedSrcSize>=0xFFFFFFFFU) :   /* 0-3 */
-                      0;
+                     (pledgedSrcSize>=256) + (pledgedSrcSize>=65536+256) + (pledgedSrcSize>=0xFFFFFFFFU) : 0;  /* 0-3 */
     BYTE  const frameHeaderDecriptionByte = (BYTE)(dictIDSizeCode + (checksumFlag<<2) + (singleSegment<<5) + (fcsCode<<6) );
     size_t pos;
 
     if (dstCapacity < ZSTD_frameHeaderSize_max) return ERROR(dstSize_tooSmall);
-    DEBUGLOG(5, "ZSTD_writeFrameHeader : dictIDFlag : %u \n", !params.fParams.noDictIDFlag);
-    DEBUGLOG(5, "ZSTD_writeFrameHeader : dictID : %u \n", dictID);
-    DEBUGLOG(5, "ZSTD_writeFrameHeader : dictIDSizeCode : %u \n", dictIDSizeCode);
+    DEBUGLOG(5, "ZSTD_writeFrameHeader : dictIDFlag : %u ; dictID : %u ; dictIDSizeCode : %u",
+                !params.fParams.noDictIDFlag, dictID,  dictIDSizeCode);
 
     MEM_writeLE32(dst, ZSTD_MAGICNUMBER);
     op[4] = frameHeaderDecriptionByte; pos=5;
     if (!singleSegment) op[pos++] = windowLogByte;
     switch(dictIDSizeCode)
     {
-        default:   /* impossible */
+        default:  assert(0); /* impossible */
         case 0 : break;
         case 1 : op[pos] = (BYTE)(dictID); pos++; break;
         case 2 : MEM_writeLE16(op+pos, (U16)dictID); pos+=2; break;
@@ -2545,7 +2937,7 @@ static size_t ZSTD_writeFrameHeader(void* dst, size_t dstCapacity,
     }
     switch(fcsCode)
     {
-        default:   /* impossible */
+        default:  assert(0); /* impossible */
         case 0 : if (singleSegment) op[pos++] = (BYTE)(pledgedSrcSize); break;
         case 1 : MEM_writeLE16(op+pos, (U16)(pledgedSrcSize-256)); pos+=2; break;
         case 2 : MEM_writeLE32(op+pos, (U32)(pledgedSrcSize)); pos+=4; break;
@@ -2563,10 +2955,13 @@ static size_t ZSTD_compressContinue_internal (ZSTD_CCtx* cctx,
     const BYTE* const ip = (const BYTE*) src;
     size_t fhSize = 0;
 
+    DEBUGLOG(5, "ZSTD_compressContinue_internal");
+    DEBUGLOG(5, "stage: %u", cctx->stage);
     if (cctx->stage==ZSTDcs_created) return ERROR(stage_wrong);   /* missing init (ZSTD_compressBegin) */
 
     if (frame && (cctx->stage==ZSTDcs_init)) {
-        fhSize = ZSTD_writeFrameHeader(dst, dstCapacity, cctx->params, cctx->frameContentSize, cctx->dictID);
+        fhSize = ZSTD_writeFrameHeader(dst, dstCapacity, cctx->appliedParams,
+                                cctx->pledgedSrcSizePlusOne-1, cctx->dictID);
         if (ZSTD_isError(fhSize)) return fhSize;
         dstCapacity -= fhSize;
         dst = (char*)dst + fhSize;
@@ -2596,7 +2991,7 @@ static size_t ZSTD_compressContinue_internal (ZSTD_CCtx* cctx,
 
     if (srcSize) {
         size_t const cSize = frame ?
-                             ZSTD_compress_generic (cctx, dst, dstCapacity, src, srcSize, lastFrameChunk) :
+                             ZSTD_compress_frameChunk (cctx, dst, dstCapacity, src, srcSize, lastFrameChunk) :
                              ZSTD_compressBlock_internal (cctx, dst, dstCapacity, src, srcSize);
         if (ZSTD_isError(cSize)) return cSize;
         cctx->consumedSrcSize += srcSize;
@@ -2614,14 +3009,18 @@ size_t ZSTD_compressContinue (ZSTD_CCtx* cctx,
 }
 
 
-size_t ZSTD_getBlockSizeMax(ZSTD_CCtx* cctx)
+size_t ZSTD_getBlockSize(const ZSTD_CCtx* cctx)
 {
-    return MIN (ZSTD_BLOCKSIZE_ABSOLUTEMAX, 1 << cctx->params.cParams.windowLog);
+    U32 const cLevel = cctx->compressionLevel;
+    ZSTD_compressionParameters cParams = (cLevel == ZSTD_CLEVEL_CUSTOM) ?
+                                        cctx->appliedParams.cParams :
+                                        ZSTD_getCParams(cLevel, 0, 0);
+    return MIN (ZSTD_BLOCKSIZE_MAX, 1 << cParams.windowLog);
 }
 
 size_t ZSTD_compressBlock(ZSTD_CCtx* cctx, void* dst, size_t dstCapacity, const void* src, size_t srcSize)
 {
-    size_t const blockSizeMax = ZSTD_getBlockSizeMax(cctx);
+    size_t const blockSizeMax = ZSTD_getBlockSize(cctx);
     if (srcSize > blockSizeMax) return ERROR(srcSize_wrong);
     return ZSTD_compressContinue_internal(cctx, dst, dstCapacity, src, srcSize, 0 /* frame mode */, 0 /* last chunk */);
 }
@@ -2645,32 +3044,32 @@ static size_t ZSTD_loadDictionaryContent(ZSTD_CCtx* zc, const void* src, size_t
     zc->nextSrc = iend;
     if (srcSize <= HASH_READ_SIZE) return 0;
 
-    switch(zc->params.cParams.strategy)
+    switch(zc->appliedParams.cParams.strategy)
     {
     case ZSTD_fast:
-        ZSTD_fillHashTable (zc, iend, zc->params.cParams.searchLength);
+        ZSTD_fillHashTable (zc, iend, zc->appliedParams.cParams.searchLength);
         break;
 
     case ZSTD_dfast:
-        ZSTD_fillDoubleHashTable (zc, iend, zc->params.cParams.searchLength);
+        ZSTD_fillDoubleHashTable (zc, iend, zc->appliedParams.cParams.searchLength);
         break;
 
     case ZSTD_greedy:
     case ZSTD_lazy:
     case ZSTD_lazy2:
         if (srcSize >= HASH_READ_SIZE)
-            ZSTD_insertAndFindFirstIndex(zc, iend-HASH_READ_SIZE, zc->params.cParams.searchLength);
+            ZSTD_insertAndFindFirstIndex(zc, iend-HASH_READ_SIZE, zc->appliedParams.cParams.searchLength);
         break;
 
     case ZSTD_btlazy2:
     case ZSTD_btopt:
-    case ZSTD_btopt2:
+    case ZSTD_btultra:
         if (srcSize >= HASH_READ_SIZE)
-            ZSTD_updateTree(zc, iend-HASH_READ_SIZE, iend, 1 << zc->params.cParams.searchLog, zc->params.cParams.searchLength);
+            ZSTD_updateTree(zc, iend-HASH_READ_SIZE, iend, 1 << zc->appliedParams.cParams.searchLog, zc->appliedParams.cParams.searchLength);
         break;
 
     default:
-        return ERROR(GENERIC);   /* strategy doesn't exist; impossible */
+        assert(0);  /* not possible : not a valid strategy id */
     }
 
     zc->nextToUpdate = (U32)(iend - zc->base);
@@ -2710,7 +3109,7 @@ static size_t ZSTD_loadZstdDictionary(ZSTD_CCtx* cctx, const void* dict, size_t
     BYTE scratchBuffer[1<<MAX(MLFSELog,LLFSELog)];
 
     dictPtr += 4;   /* skip magic number */
-    cctx->dictID = cctx->params.fParams.noDictIDFlag ? 0 :  MEM_readLE32(dictPtr);
+    cctx->dictID = cctx->appliedParams.fParams.noDictIDFlag ? 0 :  MEM_readLE32(dictPtr);
     dictPtr += 4;
 
     {   size_t const hufHeaderSize = HUF_readCTable(cctx->hufCTable, 255, dictPtr, dictEnd-dictPtr);
@@ -2781,28 +3180,56 @@ static size_t ZSTD_loadZstdDictionary(ZSTD_CCtx* cctx, const void* dict, size_t
 
 /** ZSTD_compress_insertDictionary() :
 *   @return : 0, or an error code */
-static size_t ZSTD_compress_insertDictionary(ZSTD_CCtx* cctx, const void* dict, size_t dictSize)
+static size_t ZSTD_compress_insertDictionary(ZSTD_CCtx* cctx,
+                                       const void* dict, size_t dictSize,
+                                             ZSTD_dictMode_e dictMode)
 {
+    DEBUGLOG(5, "ZSTD_compress_insertDictionary");
     if ((dict==NULL) || (dictSize<=8)) return 0;
 
-    /* dict as pure content */
-    if ((MEM_readLE32(dict) != ZSTD_DICT_MAGIC) || (cctx->forceRawDict))
+    /* dict restricted modes */
+    if (dictMode==ZSTD_dm_rawContent)
         return ZSTD_loadDictionaryContent(cctx, dict, dictSize);
 
-    /* dict as zstd dictionary */
+    if (MEM_readLE32(dict) != ZSTD_MAGIC_DICTIONARY) {
+        if (dictMode == ZSTD_dm_auto) {
+            DEBUGLOG(5, "raw content dictionary detected");
+            return ZSTD_loadDictionaryContent(cctx, dict, dictSize);
+        }
+        if (dictMode == ZSTD_dm_fullDict)
+            return ERROR(dictionary_wrong);
+        assert(0);   /* impossible */
+    }
+
+    /* dict as full zstd dictionary */
     return ZSTD_loadZstdDictionary(cctx, dict, dictSize);
 }
 
 /*! ZSTD_compressBegin_internal() :
-*   @return : 0, or an error code */
+ * @return : 0, or an error code */
 static size_t ZSTD_compressBegin_internal(ZSTD_CCtx* cctx,
                              const void* dict, size_t dictSize,
-                                   ZSTD_parameters params, U64 pledgedSrcSize)
+                             ZSTD_dictMode_e dictMode,
+                             const ZSTD_CDict* cdict,
+                                   ZSTD_parameters params, U64 pledgedSrcSize,
+                                   ZSTD_buffered_policy_e zbuff)
 {
-    ZSTD_compResetPolicy_e const crp = dictSize ? ZSTDcrp_fullReset : ZSTDcrp_continue;
+    DEBUGLOG(4, "ZSTD_compressBegin_internal");
+    DEBUGLOG(4, "dict ? %s", dict ? "dict" : (cdict ? "cdict" : "none"));
+    DEBUGLOG(4, "dictMode : %u", (U32)dictMode);
+    /* params are supposed to be fully validated at this point */
     assert(!ZSTD_isError(ZSTD_checkCParams(params.cParams)));
-    CHECK_F(ZSTD_resetCCtx_internal(cctx, params, pledgedSrcSize, crp));
-    return ZSTD_compress_insertDictionary(cctx, dict, dictSize);
+    assert(!((dict) && (cdict)));  /* either dict or cdict, not both */
+
+    if (cdict && cdict->dictContentSize>0) {
+        return ZSTD_copyCCtx_internal(cctx, cdict->refContext,
+                                      params.fParams, pledgedSrcSize,
+                                      zbuff);
+    }
+
+    CHECK_F( ZSTD_resetCCtx_internal(cctx, params, pledgedSrcSize,
+                                     ZSTDcrp_continue, zbuff) );
+    return ZSTD_compress_insertDictionary(cctx, dict, dictSize, dictMode);
 }
 
 
@@ -2814,14 +3241,16 @@ size_t ZSTD_compressBegin_advanced(ZSTD_CCtx* cctx,
 {
     /* compression parameters verification and optimization */
     CHECK_F(ZSTD_checkCParams(params.cParams));
-    return ZSTD_compressBegin_internal(cctx, dict, dictSize, params, pledgedSrcSize);
+    return ZSTD_compressBegin_internal(cctx, dict, dictSize, ZSTD_dm_auto, NULL,
+                                    params, pledgedSrcSize, ZSTDb_not_buffered);
 }
 
 
 size_t ZSTD_compressBegin_usingDict(ZSTD_CCtx* cctx, const void* dict, size_t dictSize, int compressionLevel)
 {
     ZSTD_parameters const params = ZSTD_getParams(compressionLevel, 0, dictSize);
-    return ZSTD_compressBegin_internal(cctx, dict, dictSize, params, 0);
+    return ZSTD_compressBegin_internal(cctx, dict, dictSize, ZSTD_dm_auto, NULL,
+                                       params, 0, ZSTDb_not_buffered);
 }
 
 
@@ -2840,11 +3269,12 @@ static size_t ZSTD_writeEpilogue(ZSTD_CCtx* cctx, void* dst, size_t dstCapacity)
     BYTE* op = ostart;
     size_t fhSize = 0;
 
+    DEBUGLOG(5, "ZSTD_writeEpilogue");
     if (cctx->stage == ZSTDcs_created) return ERROR(stage_wrong);  /* init missing */
 
     /* special case : empty frame */
     if (cctx->stage == ZSTDcs_init) {
-        fhSize = ZSTD_writeFrameHeader(dst, dstCapacity, cctx->params, 0, 0);
+        fhSize = ZSTD_writeFrameHeader(dst, dstCapacity, cctx->appliedParams, 0, 0);
         if (ZSTD_isError(fhSize)) return fhSize;
         dstCapacity -= fhSize;
         op += fhSize;
@@ -2860,7 +3290,7 @@ static size_t ZSTD_writeEpilogue(ZSTD_CCtx* cctx, void* dst, size_t dstCapacity)
         dstCapacity -= ZSTD_blockHeaderSize;
     }
 
-    if (cctx->params.fParams.checksumFlag) {
+    if (cctx->appliedParams.fParams.checksumFlag) {
         U32 const checksum = (U32) XXH64_digest(&cctx->xxhState);
         if (dstCapacity<4) return ERROR(dstSize_tooSmall);
         MEM_writeLE32(op, checksum);
@@ -2877,13 +3307,19 @@ size_t ZSTD_compressEnd (ZSTD_CCtx* cctx,
                    const void* src, size_t srcSize)
 {
     size_t endResult;
-    size_t const cSize = ZSTD_compressContinue_internal(cctx, dst, dstCapacity, src, srcSize, 1 /* frame mode */, 1 /* last chunk */);
+    size_t const cSize = ZSTD_compressContinue_internal(cctx,
+                                dst, dstCapacity, src, srcSize,
+                                1 /* frame mode */, 1 /* last chunk */);
     if (ZSTD_isError(cSize)) return cSize;
     endResult = ZSTD_writeEpilogue(cctx, (char*)dst + cSize, dstCapacity-cSize);
     if (ZSTD_isError(endResult)) return endResult;
-    if (cctx->params.fParams.contentSizeFlag) {  /* control src size */
-        if (cctx->frameContentSize != cctx->consumedSrcSize) return ERROR(srcSize_wrong);
-    }
+    if (cctx->appliedParams.fParams.contentSizeFlag) {  /* control src size */
+        DEBUGLOG(5, "end of frame : controlling src size");
+        if (cctx->pledgedSrcSizePlusOne != cctx->consumedSrcSize+1) {
+            DEBUGLOG(5, "error : pledgedSrcSize = %u, while realSrcSize = %u",
+                (U32)cctx->pledgedSrcSizePlusOne-1, (U32)cctx->consumedSrcSize);
+            return ERROR(srcSize_wrong);
+    }   }
     return cSize + endResult;
 }
 
@@ -2894,7 +3330,8 @@ static size_t ZSTD_compress_internal (ZSTD_CCtx* cctx,
                          const void* dict,size_t dictSize,
                                ZSTD_parameters params)
 {
-    CHECK_F(ZSTD_compressBegin_internal(cctx, dict, dictSize, params, srcSize));
+    CHECK_F( ZSTD_compressBegin_internal(cctx, dict, dictSize, ZSTD_dm_auto, NULL,
+                                         params, srcSize, ZSTDb_not_buffered) );
     return ZSTD_compressEnd(cctx, dst,  dstCapacity, src, srcSize);
 }
 
@@ -2926,25 +3363,36 @@ size_t ZSTD_compress(void* dst, size_t dstCapacity, const void* src, size_t srcS
     size_t result;
     ZSTD_CCtx ctxBody;
     memset(&ctxBody, 0, sizeof(ctxBody));
-    memcpy(&ctxBody.customMem, &defaultCustomMem, sizeof(ZSTD_customMem));
+    ctxBody.customMem = ZSTD_defaultCMem;
     result = ZSTD_compressCCtx(&ctxBody, dst, dstCapacity, src, srcSize, compressionLevel);
-    ZSTD_free(ctxBody.workSpace, defaultCustomMem);  /* can't free ctxBody itself, as it's on stack; free only heap content */
+    ZSTD_free(ctxBody.workSpace, ZSTD_defaultCMem);  /* can't free ctxBody itself, as it's on stack; free only heap content */
     return result;
 }
 
 
 /* =====  Dictionary API  ===== */
 
-struct ZSTD_CDict_s {
-    void* dictBuffer;
-    const void* dictContent;
-    size_t dictContentSize;
-    ZSTD_CCtx* refContext;
-};  /* typedef'd tp ZSTD_CDict within "zstd.h" */
+/*! ZSTD_estimateCDictSize_advanced() :
+ *  Estimate amount of memory that will be needed to create a dictionary with following arguments */
+size_t ZSTD_estimateCDictSize_advanced(size_t dictSize, ZSTD_compressionParameters cParams, unsigned byReference)
+{
+    DEBUGLOG(5, "sizeof(ZSTD_CDict) : %u", (U32)sizeof(ZSTD_CDict));
+    DEBUGLOG(5, "CCtx estimate : %u", (U32)ZSTD_estimateCCtxSize_advanced(cParams));
+    return sizeof(ZSTD_CDict) + ZSTD_estimateCCtxSize_advanced(cParams)
+           + (byReference ? 0 : dictSize);
+}
+
+size_t ZSTD_estimateCDictSize(size_t dictSize, int compressionLevel)
+{
+    ZSTD_compressionParameters const cParams = ZSTD_getCParams(compressionLevel, 0, dictSize);
+    return ZSTD_estimateCDictSize_advanced(dictSize, cParams, 0);
+}
 
 size_t ZSTD_sizeof_CDict(const ZSTD_CDict* cdict)
 {
     if (cdict==NULL) return 0;   /* support sizeof on NULL */
+    DEBUGLOG(5, "sizeof(*cdict) : %u", (U32)sizeof(*cdict));
+    DEBUGLOG(5, "ZSTD_sizeof_CCtx : %u", (U32)ZSTD_sizeof_CCtx(cdict->refContext));
     return ZSTD_sizeof_CCtx(cdict->refContext) + (cdict->dictBuffer ? cdict->dictContentSize : 0) + sizeof(*cdict);
 }
 
@@ -2956,13 +3404,46 @@ static ZSTD_parameters ZSTD_makeParams(ZSTD_compressionParameters cParams, ZSTD_
     return params;
 }
 
-ZSTD_CDict* ZSTD_createCDict_advanced(const void* dictBuffer, size_t dictSize, unsigned byReference,
+static size_t ZSTD_initCDict_internal(
+                    ZSTD_CDict* cdict,
+              const void* dictBuffer, size_t dictSize,
+                    unsigned byReference, ZSTD_dictMode_e dictMode,
+                    ZSTD_compressionParameters cParams)
+{
+    DEBUGLOG(5, "ZSTD_initCDict_internal, mode %u", (U32)dictMode);
+    if ((byReference) || (!dictBuffer) || (!dictSize)) {
+        cdict->dictBuffer = NULL;
+        cdict->dictContent = dictBuffer;
+    } else {
+        void* const internalBuffer = ZSTD_malloc(dictSize, cdict->refContext->customMem);
+        cdict->dictBuffer = internalBuffer;
+        cdict->dictContent = internalBuffer;
+        if (!internalBuffer) return ERROR(memory_allocation);
+        memcpy(internalBuffer, dictBuffer, dictSize);
+    }
+    cdict->dictContentSize = dictSize;
+
+    {   ZSTD_frameParameters const fParams = { 0 /* contentSizeFlag */,
+                    0 /* checksumFlag */, 0 /* noDictIDFlag */ };  /* dummy */
+        ZSTD_parameters const params = ZSTD_makeParams(cParams, fParams);
+        CHECK_F( ZSTD_compressBegin_internal(cdict->refContext,
+                                        cdict->dictContent, dictSize, dictMode,
+                                        NULL,
+                                        params, ZSTD_CONTENTSIZE_UNKNOWN,
+                                        ZSTDb_not_buffered) );
+    }
+
+    return 0;
+}
+
+ZSTD_CDict* ZSTD_createCDict_advanced(const void* dictBuffer, size_t dictSize,
+                                      unsigned byReference, ZSTD_dictMode_e dictMode,
                                       ZSTD_compressionParameters cParams, ZSTD_customMem customMem)
 {
-    if (!customMem.customAlloc && !customMem.customFree) customMem = defaultCustomMem;
-    if (!customMem.customAlloc || !customMem.customFree) return NULL;
+    DEBUGLOG(5, "ZSTD_createCDict_advanced, mode %u", (U32)dictMode);
+    if (!customMem.customAlloc ^ !customMem.customFree) return NULL;
 
-    {   ZSTD_CDict* const cdict = (ZSTD_CDict*) ZSTD_malloc(sizeof(ZSTD_CDict), customMem);
+    {   ZSTD_CDict* const cdict = (ZSTD_CDict*)ZSTD_malloc(sizeof(ZSTD_CDict), customMem);
         ZSTD_CCtx* const cctx = ZSTD_createCCtx_advanced(customMem);
 
         if (!cdict || !cctx) {
@@ -2970,46 +3451,34 @@ ZSTD_CDict* ZSTD_createCDict_advanced(const void* dictBuffer, size_t dictSize, u
             ZSTD_freeCCtx(cctx);
             return NULL;
         }
+        cdict->refContext = cctx;
 
-        if ((byReference) || (!dictBuffer) || (!dictSize)) {
-            cdict->dictBuffer = NULL;
-            cdict->dictContent = dictBuffer;
-        } else {
-            void* const internalBuffer = ZSTD_malloc(dictSize, customMem);
-            if (!internalBuffer) { ZSTD_free(cctx, customMem); ZSTD_free(cdict, customMem); return NULL; }
-            memcpy(internalBuffer, dictBuffer, dictSize);
-            cdict->dictBuffer = internalBuffer;
-            cdict->dictContent = internalBuffer;
+        if (ZSTD_isError( ZSTD_initCDict_internal(cdict,
+                                        dictBuffer, dictSize,
+                                        byReference, dictMode,
+                                        cParams) )) {
+            ZSTD_freeCDict(cdict);
+            return NULL;
         }
 
-        {   ZSTD_frameParameters const fParams = { 0 /* contentSizeFlag */, 0 /* checksumFlag */, 0 /* noDictIDFlag */ };   /* dummy */
-            ZSTD_parameters const params = ZSTD_makeParams(cParams, fParams);
-            size_t const errorCode = ZSTD_compressBegin_advanced(cctx, cdict->dictContent, dictSize, params, 0);
-            if (ZSTD_isError(errorCode)) {
-                ZSTD_free(cdict->dictBuffer, customMem);
-                ZSTD_free(cdict, customMem);
-                ZSTD_freeCCtx(cctx);
-                return NULL;
-        }   }
-
-        cdict->refContext = cctx;
-        cdict->dictContentSize = dictSize;
         return cdict;
     }
 }
 
 ZSTD_CDict* ZSTD_createCDict(const void* dict, size_t dictSize, int compressionLevel)
 {
-    ZSTD_customMem const allocator = { NULL, NULL, NULL };
     ZSTD_compressionParameters cParams = ZSTD_getCParams(compressionLevel, 0, dictSize);
-    return ZSTD_createCDict_advanced(dict, dictSize, 0, cParams, allocator);
+    return ZSTD_createCDict_advanced(dict, dictSize,
+                                     0 /* byReference */, ZSTD_dm_auto,
+                                     cParams, ZSTD_defaultCMem);
 }
 
 ZSTD_CDict* ZSTD_createCDict_byReference(const void* dict, size_t dictSize, int compressionLevel)
 {
-    ZSTD_customMem const allocator = { NULL, NULL, NULL };
     ZSTD_compressionParameters cParams = ZSTD_getCParams(compressionLevel, 0, dictSize);
-    return ZSTD_createCDict_advanced(dict, dictSize, 1, cParams, allocator);
+    return ZSTD_createCDict_advanced(dict, dictSize,
+                                     1 /* byReference */, ZSTD_dm_auto,
+                                     cParams, ZSTD_defaultCMem);
 }
 
 size_t ZSTD_freeCDict(ZSTD_CDict* cdict)
@@ -3023,7 +3492,54 @@ size_t ZSTD_freeCDict(ZSTD_CDict* cdict)
     }
 }
 
-static ZSTD_parameters ZSTD_getParamsFromCDict(const ZSTD_CDict* cdict) {
+/*! ZSTD_initStaticCDict_advanced() :
+ *  Generate a digested dictionary in provided memory area.
+ *  workspace: The memory area to emplace the dictionary into.
+ *             Provided pointer must 8-bytes aligned.
+ *             It must outlive dictionary usage.
+ *  workspaceSize: Use ZSTD_estimateCDictSize()
+ *                 to determine how large workspace must be.
+ *  cParams : use ZSTD_getCParams() to transform a compression level
+ *            into its relevants cParams.
+ * @return : pointer to ZSTD_CDict*, or NULL if error (size too small)
+ *  Note : there is no corresponding "free" function.
+ *         Since workspace was allocated externally, it must be freed externally.
+ */
+ZSTD_CDict* ZSTD_initStaticCDict(void* workspace, size_t workspaceSize,
+                           const void* dict, size_t dictSize,
+                                 unsigned byReference, ZSTD_dictMode_e dictMode,
+                                 ZSTD_compressionParameters cParams)
+{
+    size_t const cctxSize = ZSTD_estimateCCtxSize_advanced(cParams);
+    size_t const neededSize = sizeof(ZSTD_CDict) + (byReference ? 0 : dictSize)
+                            + cctxSize;
+    ZSTD_CDict* const cdict = (ZSTD_CDict*) workspace;
+    void* ptr;
+    DEBUGLOG(5, "(size_t)workspace & 7 : %u", (U32)(size_t)workspace & 7);
+    if ((size_t)workspace & 7) return NULL;  /* 8-aligned */
+    DEBUGLOG(5, "(workspaceSize < neededSize) : (%u < %u) => %u",
+        (U32)workspaceSize, (U32)neededSize, (U32)(workspaceSize < neededSize));
+    if (workspaceSize < neededSize) return NULL;
+
+    if (!byReference) {
+        memcpy(cdict+1, dict, dictSize);
+        dict = cdict+1;
+        ptr = (char*)workspace + sizeof(ZSTD_CDict) + dictSize;
+    } else {
+        ptr = cdict+1;
+    }
+    cdict->refContext = ZSTD_initStaticCCtx(ptr, cctxSize);
+
+    if (ZSTD_isError( ZSTD_initCDict_internal(cdict,
+                                              dict, dictSize,
+                                              1 /* byReference */, dictMode,
+                                              cParams) ))
+        return NULL;
+
+    return cdict;
+}
+
+ZSTD_parameters ZSTD_getParamsFromCDict(const ZSTD_CDict* cdict) {
     return ZSTD_getParamsFromCCtx(cdict->refContext);
 }
 
@@ -3033,16 +3549,16 @@ size_t ZSTD_compressBegin_usingCDict_advanced(
     ZSTD_CCtx* const cctx, const ZSTD_CDict* const cdict,
     ZSTD_frameParameters const fParams, unsigned long long const pledgedSrcSize)
 {
-    if (cdict==NULL) return ERROR(GENERIC);  /* does not support NULL cdict */
-    DEBUGLOG(5, "ZSTD_compressBegin_usingCDict_advanced : dictIDFlag == %u \n", !fParams.noDictIDFlag);
-    if (cdict->dictContentSize)
-        CHECK_F( ZSTD_copyCCtx_internal(cctx, cdict->refContext, fParams, pledgedSrcSize) )
-    else {
-        ZSTD_parameters params = cdict->refContext->params;
+    if (cdict==NULL) return ERROR(dictionary_wrong);
+    {   ZSTD_parameters params = cdict->refContext->appliedParams;
         params.fParams = fParams;
-        CHECK_F(ZSTD_compressBegin_internal(cctx, NULL, 0, params, pledgedSrcSize));
+        DEBUGLOG(5, "ZSTD_compressBegin_usingCDict_advanced");
+        return ZSTD_compressBegin_internal(cctx,
+                                           NULL, 0, ZSTD_dm_auto,
+                                           cdict,
+                                           params, pledgedSrcSize,
+                                           ZSTDb_not_buffered);
     }
-    return 0;
 }
 
 /* ZSTD_compressBegin_usingCDict() :
@@ -3051,7 +3567,7 @@ size_t ZSTD_compressBegin_usingCDict_advanced(
 size_t ZSTD_compressBegin_usingCDict(ZSTD_CCtx* cctx, const ZSTD_CDict* cdict)
 {
     ZSTD_frameParameters const fParams = { 0 /*content*/, 0 /*checksum*/, 0 /*noDictID*/ };
-    DEBUGLOG(5, "ZSTD_compressBegin_usingCDict : dictIDFlag == %u \n", !fParams.noDictIDFlag);
+    DEBUGLOG(5, "ZSTD_compressBegin_usingCDict : dictIDFlag == %u", !fParams.noDictIDFlag);
     return ZSTD_compressBegin_usingCDict_advanced(cctx, cdict, fParams, 0);
 }
 
@@ -3084,176 +3600,133 @@ size_t ZSTD_compress_usingCDict(ZSTD_CCtx* cctx,
 *  Streaming
 ********************************************************************/
 
-typedef enum { zcss_init, zcss_load, zcss_flush, zcss_final } ZSTD_cStreamStage;
-
-struct ZSTD_CStream_s {
-    ZSTD_CCtx* cctx;
-    ZSTD_CDict* cdictLocal;
-    const ZSTD_CDict* cdict;
-    char*  inBuff;
-    size_t inBuffSize;
-    size_t inToCompress;
-    size_t inBuffPos;
-    size_t inBuffTarget;
-    size_t blockSize;
-    char*  outBuff;
-    size_t outBuffSize;
-    size_t outBuffContentSize;
-    size_t outBuffFlushedSize;
-    ZSTD_cStreamStage stage;
-    U32    checksum;
-    U32    frameEnded;
-    U64    pledgedSrcSize;
-    ZSTD_parameters params;
-    ZSTD_customMem customMem;
-};   /* typedef'd to ZSTD_CStream within "zstd.h" */
-
 ZSTD_CStream* ZSTD_createCStream(void)
 {
-    return ZSTD_createCStream_advanced(defaultCustomMem);
+    return ZSTD_createCStream_advanced(ZSTD_defaultCMem);
 }
 
-ZSTD_CStream* ZSTD_createCStream_advanced(ZSTD_customMem customMem)
+ZSTD_CStream* ZSTD_initStaticCStream(void *workspace, size_t workspaceSize)
 {
-    ZSTD_CStream* zcs;
-
-    if (!customMem.customAlloc && !customMem.customFree) customMem = defaultCustomMem;
-    if (!customMem.customAlloc || !customMem.customFree) return NULL;
+    return ZSTD_initStaticCCtx(workspace, workspaceSize);
+}
 
-    zcs = (ZSTD_CStream*)ZSTD_malloc(sizeof(ZSTD_CStream), customMem);
-    if (zcs==NULL) return NULL;
-    memset(zcs, 0, sizeof(ZSTD_CStream));
-    memcpy(&zcs->customMem, &customMem, sizeof(ZSTD_customMem));
-    zcs->cctx = ZSTD_createCCtx_advanced(customMem);
-    if (zcs->cctx == NULL) { ZSTD_freeCStream(zcs); return NULL; }
-    return zcs;
+ZSTD_CStream* ZSTD_createCStream_advanced(ZSTD_customMem customMem)
+{   /* CStream and CCtx are now same object */
+    return ZSTD_createCCtx_advanced(customMem);
 }
 
 size_t ZSTD_freeCStream(ZSTD_CStream* zcs)
 {
-    if (zcs==NULL) return 0;   /* support free on NULL */
-    {   ZSTD_customMem const cMem = zcs->customMem;
-        ZSTD_freeCCtx(zcs->cctx);
-        zcs->cctx = NULL;
-        ZSTD_freeCDict(zcs->cdictLocal);
-        zcs->cdictLocal = NULL;
-        ZSTD_free(zcs->inBuff, cMem);
-        zcs->inBuff = NULL;
-        ZSTD_free(zcs->outBuff, cMem);
-        zcs->outBuff = NULL;
-        ZSTD_free(zcs, cMem);
-        return 0;
-    }
+    return ZSTD_freeCCtx(zcs);   /* same object */
 }
 
 
+
 /*======   Initialization   ======*/
 
-size_t ZSTD_CStreamInSize(void)  { return ZSTD_BLOCKSIZE_ABSOLUTEMAX; }
+size_t ZSTD_CStreamInSize(void)  { return ZSTD_BLOCKSIZE_MAX; }
 
 size_t ZSTD_CStreamOutSize(void)
 {
-    return ZSTD_compressBound(ZSTD_BLOCKSIZE_ABSOLUTEMAX) + ZSTD_blockHeaderSize + 4 /* 32-bits hash */ ;
+    return ZSTD_compressBound(ZSTD_BLOCKSIZE_MAX) + ZSTD_blockHeaderSize + 4 /* 32-bits hash */ ;
 }
 
-static size_t ZSTD_resetCStream_internal(ZSTD_CStream* zcs, unsigned long long pledgedSrcSize)
+static size_t ZSTD_resetCStream_internal(ZSTD_CStream* zcs,
+                    const void* dict, size_t dictSize, ZSTD_dictMode_e dictMode,
+                    const ZSTD_CDict* cdict,
+                    ZSTD_parameters params, unsigned long long pledgedSrcSize)
 {
-    if (zcs->inBuffSize==0) return ERROR(stage_wrong);   /* zcs has not been init at least once => can't reset */
-
-    DEBUGLOG(5, "ZSTD_resetCStream_internal : dictIDFlag == %u \n", !zcs->params.fParams.noDictIDFlag);
+    DEBUGLOG(4, "ZSTD_resetCStream_internal");
+    /* params are supposed to be fully validated at this point */
+    assert(!ZSTD_isError(ZSTD_checkCParams(params.cParams)));
+    assert(!((dict) && (cdict)));  /* either dict or cdict, not both */
 
-    if (zcs->cdict) CHECK_F(ZSTD_compressBegin_usingCDict_advanced(zcs->cctx, zcs->cdict, zcs->params.fParams, pledgedSrcSize))
-    else CHECK_F(ZSTD_compressBegin_internal(zcs->cctx, NULL, 0, zcs->params, pledgedSrcSize));
+    CHECK_F( ZSTD_compressBegin_internal(zcs,
+                                        dict, dictSize, dictMode,
+                                        cdict,
+                                        params, pledgedSrcSize,
+                                        ZSTDb_buffered) );
 
     zcs->inToCompress = 0;
     zcs->inBuffPos = 0;
     zcs->inBuffTarget = zcs->blockSize;
     zcs->outBuffContentSize = zcs->outBuffFlushedSize = 0;
-    zcs->stage = zcss_load;
+    zcs->streamStage = zcss_load;
     zcs->frameEnded = 0;
-    zcs->pledgedSrcSize = pledgedSrcSize;
     return 0;   /* ready to go */
 }
 
 size_t ZSTD_resetCStream(ZSTD_CStream* zcs, unsigned long long pledgedSrcSize)
 {
-
-    zcs->params.fParams.contentSizeFlag = (pledgedSrcSize > 0);
-    DEBUGLOG(5, "ZSTD_resetCStream : dictIDFlag == %u \n", !zcs->params.fParams.noDictIDFlag);
-    return ZSTD_resetCStream_internal(zcs, pledgedSrcSize);
+    ZSTD_parameters params = zcs->requestedParams;
+    params.fParams.contentSizeFlag = (pledgedSrcSize > 0);
+    DEBUGLOG(5, "ZSTD_resetCStream");
+    if (zcs->compressionLevel != ZSTD_CLEVEL_CUSTOM) {
+        params.cParams = ZSTD_getCParams(zcs->compressionLevel, pledgedSrcSize, 0 /* dictSize */);
+    }
+    return ZSTD_resetCStream_internal(zcs, NULL, 0, zcs->dictMode, zcs->cdict, params, pledgedSrcSize);
 }
 
-/* ZSTD_initCStream_internal() :
- * params are supposed validated at this stage
- * and zcs->cdict is supposed to be correct */
-static size_t ZSTD_initCStream_stage2(ZSTD_CStream* zcs,
-                                const ZSTD_parameters params,
-                                unsigned long long pledgedSrcSize)
+/*! ZSTD_initCStream_internal() :
+ *  Note : not static, but hidden (not exposed). Used by zstdmt_compress.c
+ *  Assumption 1 : params are valid
+ *  Assumption 2 : either dict, or cdict, is defined, not both */
+size_t ZSTD_initCStream_internal(ZSTD_CStream* zcs,
+                    const void* dict, size_t dictSize, const ZSTD_CDict* cdict,
+                    ZSTD_parameters params, unsigned long long pledgedSrcSize)
 {
+    DEBUGLOG(5, "ZSTD_initCStream_internal");
     assert(!ZSTD_isError(ZSTD_checkCParams(params.cParams)));
+    assert(!((dict) && (cdict)));  /* either dict or cdict, not both */
 
-    /* allocate buffers */
-    {   size_t const neededInBuffSize = (size_t)1 << params.cParams.windowLog;
-        if (zcs->inBuffSize < neededInBuffSize) {
-            zcs->inBuffSize = 0;
-            ZSTD_free(zcs->inBuff, zcs->customMem);
-            zcs->inBuff = (char*) ZSTD_malloc(neededInBuffSize, zcs->customMem);
-            if (zcs->inBuff == NULL) return ERROR(memory_allocation);
-            zcs->inBuffSize = neededInBuffSize;
+    if (dict && dictSize >= 8) {
+        DEBUGLOG(5, "loading dictionary of size %u", (U32)dictSize);
+        if (zcs->staticSize) {   /* static CCtx : never uses malloc */
+            /* incompatible with internal cdict creation */
+            return ERROR(memory_allocation);
         }
-        zcs->blockSize = MIN(ZSTD_BLOCKSIZE_ABSOLUTEMAX, neededInBuffSize);
-    }
-    if (zcs->outBuffSize < ZSTD_compressBound(zcs->blockSize)+1) {
-        size_t const outBuffSize = ZSTD_compressBound(zcs->blockSize)+1;
-        zcs->outBuffSize = 0;
-        ZSTD_free(zcs->outBuff, zcs->customMem);
-        zcs->outBuff = (char*) ZSTD_malloc(outBuffSize, zcs->customMem);
-        if (zcs->outBuff == NULL) return ERROR(memory_allocation);
-        zcs->outBuffSize = outBuffSize;
+        ZSTD_freeCDict(zcs->cdictLocal);
+        zcs->cdictLocal = ZSTD_createCDict_advanced(dict, dictSize,
+                                            zcs->dictContentByRef, zcs->dictMode,
+                                            params.cParams, zcs->customMem);
+        zcs->cdict = zcs->cdictLocal;
+        if (zcs->cdictLocal == NULL) return ERROR(memory_allocation);
+    } else {
+        if (cdict) {
+            ZSTD_parameters const cdictParams = ZSTD_getParamsFromCDict(cdict);
+            params.cParams = cdictParams.cParams;  /* cParams are enforced from cdict */
+        }
+        ZSTD_freeCDict(zcs->cdictLocal);
+        zcs->cdictLocal = NULL;
+        zcs->cdict = cdict;
     }
 
-    zcs->checksum = params.fParams.checksumFlag > 0;
-    zcs->params = params;
-
-    DEBUGLOG(5, "ZSTD_initCStream_stage2 : dictIDFlag == %u \n", !params.fParams.noDictIDFlag);
-    return ZSTD_resetCStream_internal(zcs, pledgedSrcSize);
+    zcs->requestedParams = params;
+    zcs->compressionLevel = ZSTD_CLEVEL_CUSTOM;
+    return ZSTD_resetCStream_internal(zcs, NULL, 0, zcs->dictMode, zcs->cdict, params, pledgedSrcSize);
 }
 
 /* ZSTD_initCStream_usingCDict_advanced() :
  * same as ZSTD_initCStream_usingCDict(), with control over frame parameters */
-size_t ZSTD_initCStream_usingCDict_advanced(ZSTD_CStream* zcs, const ZSTD_CDict* cdict, unsigned long long pledgedSrcSize, ZSTD_frameParameters fParams)
-{
-    if (!cdict) return ERROR(GENERIC);   /* cannot handle NULL cdict (does not know what to do) */
+size_t ZSTD_initCStream_usingCDict_advanced(ZSTD_CStream* zcs,
+                                            const ZSTD_CDict* cdict,
+                                            ZSTD_frameParameters fParams,
+                                            unsigned long long pledgedSrcSize)
+{   /* cannot handle NULL cdict (does not know what to do) */
+    if (!cdict) return ERROR(dictionary_wrong);
     {   ZSTD_parameters params = ZSTD_getParamsFromCDict(cdict);
         params.fParams = fParams;
-        zcs->cdict = cdict;
-        return ZSTD_initCStream_stage2(zcs, params, pledgedSrcSize);
+        return ZSTD_initCStream_internal(zcs,
+                                NULL, 0, cdict,
+                                params, pledgedSrcSize);
     }
 }
 
 /* note : cdict must outlive compression session */
 size_t ZSTD_initCStream_usingCDict(ZSTD_CStream* zcs, const ZSTD_CDict* cdict)
 {
-    ZSTD_frameParameters const fParams = { 0 /* content */, 0 /* checksum */, 0 /* noDictID */ };
-    return ZSTD_initCStream_usingCDict_advanced(zcs, cdict, 0, fParams);
-}
-
-static size_t ZSTD_initCStream_internal(ZSTD_CStream* zcs,
-                                const void* dict, size_t dictSize,
-                                ZSTD_parameters params, unsigned long long pledgedSrcSize)
-{
-    assert(!ZSTD_isError(ZSTD_checkCParams(params.cParams)));
-    zcs->cdict = NULL;
-
-    if (dict && dictSize >= 8) {
-        ZSTD_freeCDict(zcs->cdictLocal);
-        zcs->cdictLocal = ZSTD_createCDict_advanced(dict, dictSize, 0 /* copy */, params.cParams, zcs->customMem);
-        if (zcs->cdictLocal == NULL) return ERROR(memory_allocation);
-        zcs->cdict = zcs->cdictLocal;
-    }
-
-    DEBUGLOG(5, "ZSTD_initCStream_internal : dictIDFlag == %u \n", !params.fParams.noDictIDFlag);
-    return ZSTD_initCStream_stage2(zcs, params, pledgedSrcSize);
+    ZSTD_frameParameters const fParams = { 0 /* contentSize */, 0 /* checksum */, 0 /* hideDictID */ };
+    return ZSTD_initCStream_usingCDict_advanced(zcs, cdict, fParams, 0);  /* note : will check that cdict != NULL */
 }
 
 size_t ZSTD_initCStream_advanced(ZSTD_CStream* zcs,
@@ -3261,120 +3734,180 @@ size_t ZSTD_initCStream_advanced(ZSTD_CStream* zcs,
                                  ZSTD_parameters params, unsigned long long pledgedSrcSize)
 {
     CHECK_F( ZSTD_checkCParams(params.cParams) );
-    DEBUGLOG(5, "ZSTD_initCStream_advanced : dictIDFlag == %u \n", !params.fParams.noDictIDFlag);
-    return ZSTD_initCStream_internal(zcs, dict, dictSize, params, pledgedSrcSize);
+    zcs->requestedParams = params;
+    zcs->compressionLevel = ZSTD_CLEVEL_CUSTOM;
+    return ZSTD_initCStream_internal(zcs, dict, dictSize, NULL, params, pledgedSrcSize);
 }
 
 size_t ZSTD_initCStream_usingDict(ZSTD_CStream* zcs, const void* dict, size_t dictSize, int compressionLevel)
 {
     ZSTD_parameters const params = ZSTD_getParams(compressionLevel, 0, dictSize);
-    return ZSTD_initCStream_internal(zcs, dict, dictSize, params, 0);
+    zcs->compressionLevel = compressionLevel;
+    return ZSTD_initCStream_internal(zcs, dict, dictSize, NULL, params, 0);
 }
 
 size_t ZSTD_initCStream_srcSize(ZSTD_CStream* zcs, int compressionLevel, unsigned long long pledgedSrcSize)
 {
     ZSTD_parameters params = ZSTD_getParams(compressionLevel, pledgedSrcSize, 0);
     params.fParams.contentSizeFlag = (pledgedSrcSize>0);
-    return ZSTD_initCStream_internal(zcs, NULL, 0, params, pledgedSrcSize);
+    return ZSTD_initCStream_internal(zcs, NULL, 0, NULL, params, pledgedSrcSize);
 }
 
 size_t ZSTD_initCStream(ZSTD_CStream* zcs, int compressionLevel)
 {
     ZSTD_parameters const params = ZSTD_getParams(compressionLevel, 0, 0);
-    return ZSTD_initCStream_internal(zcs, NULL, 0, params, 0);
-}
-
-size_t ZSTD_sizeof_CStream(const ZSTD_CStream* zcs)
-{
-    if (zcs==NULL) return 0;   /* support sizeof on NULL */
-    return sizeof(*zcs) + ZSTD_sizeof_CCtx(zcs->cctx) + ZSTD_sizeof_CDict(zcs->cdictLocal) + zcs->outBuffSize + zcs->inBuffSize;
+    return ZSTD_initCStream_internal(zcs, NULL, 0, NULL, params, 0);
 }
 
 /*======   Compression   ======*/
 
-typedef enum { zsf_gather, zsf_flush, zsf_end } ZSTD_flush_e;
-
-MEM_STATIC size_t ZSTD_limitCopy(void* dst, size_t dstCapacity, const void* src, size_t srcSize)
+MEM_STATIC size_t ZSTD_limitCopy(void* dst, size_t dstCapacity,
+                           const void* src, size_t srcSize)
 {
     size_t const length = MIN(dstCapacity, srcSize);
-    memcpy(dst, src, length);
+    if (length) memcpy(dst, src, length);
     return length;
 }
 
-static size_t ZSTD_compressStream_generic(ZSTD_CStream* zcs,
-                              void* dst, size_t* dstCapacityPtr,
-                        const void* src, size_t* srcSizePtr,
-                              ZSTD_flush_e const flush)
+/** ZSTD_compressStream_generic():
+ *  internal function for all *compressStream*() variants and *compress_generic()
+ * @return : hint size for next input */
+size_t ZSTD_compressStream_generic(ZSTD_CStream* zcs,
+                                   ZSTD_outBuffer* output,
+                                   ZSTD_inBuffer* input,
+                                   ZSTD_EndDirective const flushMode)
 {
+    const char* const istart = (const char*)input->src;
+    const char* const iend = istart + input->size;
+    const char* ip = istart + input->pos;
+    char* const ostart = (char*)output->dst;
+    char* const oend = ostart + output->size;
+    char* op = ostart + output->pos;
     U32 someMoreWork = 1;
-    const char* const istart = (const char*)src;
-    const char* const iend = istart + *srcSizePtr;
-    const char* ip = istart;
-    char* const ostart = (char*)dst;
-    char* const oend = ostart + *dstCapacityPtr;
-    char* op = ostart;
+
+    /* check expectations */
+    DEBUGLOG(5, "ZSTD_compressStream_generic, flush=%u", (U32)flushMode);
+    assert(zcs->inBuff != NULL);
+    assert(zcs->inBuffSize>0);
+    assert(zcs->outBuff!= NULL);
+    assert(zcs->outBuffSize>0);
+    assert(output->pos <= output->size);
+    assert(input->pos <= input->size);
 
     while (someMoreWork) {
-        switch(zcs->stage)
+        switch(zcs->streamStage)
         {
-        case zcss_init: return ERROR(init_missing);   /* call ZBUFF_compressInit() first ! */
+        case zcss_init:
+            /* call ZSTD_initCStream() first ! */
+            return ERROR(init_missing);
 
         case zcss_load:
-            /* complete inBuffer */
+            if ( (flushMode == ZSTD_e_end)
+              && ((size_t)(oend-op) >= ZSTD_compressBound(iend-ip))  /* enough dstCapacity */
+              && (zcs->inBuffPos == 0) ) {
+                /* shortcut to compression pass directly into output buffer */
+                size_t const cSize = ZSTD_compressEnd(zcs,
+                                                op, oend-op, ip, iend-ip);
+                DEBUGLOG(4, "ZSTD_compressEnd : %u", (U32)cSize);
+                if (ZSTD_isError(cSize)) return cSize;
+                ip = iend;
+                op += cSize;
+                zcs->frameEnded = 1;
+                ZSTD_startNewCompression(zcs);
+                someMoreWork = 0; break;
+            }
+            /* complete loading into inBuffer */
             {   size_t const toLoad = zcs->inBuffTarget - zcs->inBuffPos;
-                size_t const loaded = ZSTD_limitCopy(zcs->inBuff + zcs->inBuffPos, toLoad, ip, iend-ip);
+                size_t const loaded = ZSTD_limitCopy(
+                                        zcs->inBuff + zcs->inBuffPos, toLoad,
+                                        ip, iend-ip);
                 zcs->inBuffPos += loaded;
                 ip += loaded;
-                if ( (zcs->inBuffPos==zcs->inToCompress) || (!flush && (toLoad != loaded)) ) {
-                    someMoreWork = 0; break;  /* not enough input to get a full block : stop there, wait for more */
-            }   }
+                if ( (flushMode == ZSTD_e_continue)
+                  && (zcs->inBuffPos < zcs->inBuffTarget) ) {
+                    /* not enough input to fill full block : stop here */
+                    someMoreWork = 0; break;
+                }
+                if ( (flushMode == ZSTD_e_flush)
+                  && (zcs->inBuffPos == zcs->inToCompress) ) {
+                    /* empty */
+                    someMoreWork = 0; break;
+                }
+            }
             /* compress current block (note : this stage cannot be stopped in the middle) */
+            DEBUGLOG(5, "stream compression stage (flushMode==%u)", flushMode);
             {   void* cDst;
                 size_t cSize;
                 size_t const iSize = zcs->inBuffPos - zcs->inToCompress;
                 size_t oSize = oend-op;
+                unsigned const lastBlock = (flushMode == ZSTD_e_end) && (ip==iend);
                 if (oSize >= ZSTD_compressBound(iSize))
-                    cDst = op;   /* compress directly into output buffer (avoid flush stage) */
+                    cDst = op;   /* compress into output buffer, to skip flush stage */
                 else
                     cDst = zcs->outBuff, oSize = zcs->outBuffSize;
-                cSize = (flush == zsf_end) ?
-                        ZSTD_compressEnd(zcs->cctx, cDst, oSize, zcs->inBuff + zcs->inToCompress, iSize) :
-                        ZSTD_compressContinue(zcs->cctx, cDst, oSize, zcs->inBuff + zcs->inToCompress, iSize);
+                cSize = lastBlock ?
+                        ZSTD_compressEnd(zcs, cDst, oSize,
+                                    zcs->inBuff + zcs->inToCompress, iSize) :
+                        ZSTD_compressContinue(zcs, cDst, oSize,
+                                    zcs->inBuff + zcs->inToCompress, iSize);
                 if (ZSTD_isError(cSize)) return cSize;
-                if (flush == zsf_end) zcs->frameEnded = 1;
+                zcs->frameEnded = lastBlock;
                 /* prepare next block */
                 zcs->inBuffTarget = zcs->inBuffPos + zcs->blockSize;
                 if (zcs->inBuffTarget > zcs->inBuffSize)
-                    zcs->inBuffPos = 0, zcs->inBuffTarget = zcs->blockSize;   /* note : inBuffSize >= blockSize */
+                    zcs->inBuffPos = 0, zcs->inBuffTarget = zcs->blockSize;
+                DEBUGLOG(5, "inBuffTarget:%u / inBuffSize:%u",
+                         (U32)zcs->inBuffTarget, (U32)zcs->inBuffSize);
+                if (!lastBlock)
+                    assert(zcs->inBuffTarget <= zcs->inBuffSize);
                 zcs->inToCompress = zcs->inBuffPos;
-                if (cDst == op) { op += cSize; break; }   /* no need to flush */
+                if (cDst == op) {  /* no need to flush */
+                    op += cSize;
+                    if (zcs->frameEnded) {
+                        DEBUGLOG(5, "Frame completed directly in outBuffer");
+                        someMoreWork = 0;
+                        ZSTD_startNewCompression(zcs);
+                    }
+                    break;
+                }
                 zcs->outBuffContentSize = cSize;
                 zcs->outBuffFlushedSize = 0;
-                zcs->stage = zcss_flush;   /* pass-through to flush stage */
+                zcs->streamStage = zcss_flush; /* pass-through to flush stage */
             }
-
+	    /* fall-through */
         case zcss_flush:
+            DEBUGLOG(5, "flush stage");
             {   size_t const toFlush = zcs->outBuffContentSize - zcs->outBuffFlushedSize;
-                size_t const flushed = ZSTD_limitCopy(op, oend-op, zcs->outBuff + zcs->outBuffFlushedSize, toFlush);
+                size_t const flushed = ZSTD_limitCopy(op, oend-op,
+                            zcs->outBuff + zcs->outBuffFlushedSize, toFlush);
+                DEBUGLOG(5, "toFlush: %u into %u ==> flushed: %u",
+                            (U32)toFlush, (U32)(oend-op), (U32)flushed);
                 op += flushed;
                 zcs->outBuffFlushedSize += flushed;
-                if (toFlush!=flushed) { someMoreWork = 0; break; }  /* dst too small to store flushed data : stop there */
+                if (toFlush!=flushed) {
+                    /* flush not fully completed, presumably because dst is too small */
+                    assert(op==oend);
+                    someMoreWork = 0;
+                    break;
+                }
                 zcs->outBuffContentSize = zcs->outBuffFlushedSize = 0;
-                zcs->stage = zcss_load;
+                if (zcs->frameEnded) {
+                    DEBUGLOG(5, "Frame completed on flush");
+                    someMoreWork = 0;
+                    ZSTD_startNewCompression(zcs);
+                    break;
+                }
+                zcs->streamStage = zcss_load;
                 break;
             }
 
-        case zcss_final:
-            someMoreWork = 0;   /* do nothing */
-            break;
-
-        default:
-            return ERROR(GENERIC);   /* impossible */
+        default: /* impossible */
+            assert(0);
         }
     }
 
-    *srcSizePtr = ip - istart;
-    *dstCapacityPtr = op - ostart;
+    input->pos = ip - istart;
+    output->pos = op - ostart;
     if (zcs->frameEnded) return 0;
     {   size_t hintInSize = zcs->inBuffTarget - zcs->inBuffPos;
         if (hintInSize==0) hintInSize = zcs->blockSize;
@@ -3384,14 +3917,86 @@ static size_t ZSTD_compressStream_generic(ZSTD_CStream* zcs,
 
 size_t ZSTD_compressStream(ZSTD_CStream* zcs, ZSTD_outBuffer* output, ZSTD_inBuffer* input)
 {
-    size_t sizeRead = input->size - input->pos;
-    size_t sizeWritten = output->size - output->pos;
-    size_t const result = ZSTD_compressStream_generic(zcs,
-                                                      (char*)(output->dst) + output->pos, &sizeWritten,
-                                                      (const char*)(input->src) + input->pos, &sizeRead, zsf_gather);
-    input->pos += sizeRead;
-    output->pos += sizeWritten;
-    return result;
+    /* check conditions */
+    if (output->pos > output->size) return ERROR(GENERIC);
+    if (input->pos  > input->size)  return ERROR(GENERIC);
+
+    return ZSTD_compressStream_generic(zcs, output, input, ZSTD_e_continue);
+}
+
+/*! ZSTDMT_initCStream_internal() :
+ *  Private use only. Init streaming operation.
+ *  expects params to be valid.
+ *  must receive dict, or cdict, or none, but not both.
+ *  @return : 0, or an error code */
+size_t ZSTDMT_initCStream_internal(ZSTDMT_CCtx* zcs,
+                    const void* dict, size_t dictSize, const ZSTD_CDict* cdict,
+                    ZSTD_parameters params, unsigned long long pledgedSrcSize);
+
+
+size_t ZSTD_compress_generic (ZSTD_CCtx* cctx,
+                              ZSTD_outBuffer* output,
+                              ZSTD_inBuffer* input,
+                              ZSTD_EndDirective endOp)
+{
+    /* check conditions */
+    if (output->pos > output->size) return ERROR(GENERIC);
+    if (input->pos  > input->size)  return ERROR(GENERIC);
+    assert(cctx!=NULL);
+
+    /* transparent initialization stage */
+    if (cctx->streamStage == zcss_init) {
+        const void* const prefix = cctx->prefix;
+        size_t const prefixSize = cctx->prefixSize;
+        ZSTD_parameters params = cctx->requestedParams;
+        if (cctx->compressionLevel != ZSTD_CLEVEL_CUSTOM)
+            params.cParams = ZSTD_getCParams(cctx->compressionLevel,
+                                cctx->pledgedSrcSizePlusOne-1, 0 /*dictSize*/);
+        cctx->prefix = NULL; cctx->prefixSize = 0;   /* single usage */
+        assert(prefix==NULL || cctx->cdict==NULL);   /* only one can be set */
+
+#ifdef ZSTD_MULTITHREAD
+        if (cctx->nbThreads > 1) {
+            DEBUGLOG(4, "call ZSTDMT_initCStream_internal as nbThreads=%u", cctx->nbThreads);
+            CHECK_F( ZSTDMT_initCStream_internal(cctx->mtctx, prefix, prefixSize, cctx->cdict, params, cctx->pledgedSrcSizePlusOne-1) );
+            cctx->streamStage = zcss_load;
+        } else
+#endif
+        {
+            CHECK_F( ZSTD_resetCStream_internal(cctx, prefix, prefixSize, cctx->dictMode, cctx->cdict, params, cctx->pledgedSrcSizePlusOne-1) );
+    }   }
+
+    /* compression stage */
+#ifdef ZSTD_MULTITHREAD
+    if (cctx->nbThreads > 1) {
+        size_t const flushMin = ZSTDMT_compressStream_generic(cctx->mtctx, output, input, endOp);
+        DEBUGLOG(5, "ZSTDMT_compressStream_generic : %u", (U32)flushMin);
+        if ( ZSTD_isError(flushMin)
+          || (endOp == ZSTD_e_end && flushMin == 0) ) { /* compression completed */
+            ZSTD_startNewCompression(cctx);
+        }
+        return flushMin;
+    }
+#endif
+
+    CHECK_F( ZSTD_compressStream_generic(cctx, output, input, endOp) );
+    DEBUGLOG(5, "completed ZSTD_compress_generic");
+    return cctx->outBuffContentSize - cctx->outBuffFlushedSize; /* remaining to flush */
+}
+
+size_t ZSTD_compress_generic_simpleArgs (
+                            ZSTD_CCtx* cctx,
+                            void* dst, size_t dstCapacity, size_t* dstPos,
+                      const void* src, size_t srcSize, size_t* srcPos,
+                            ZSTD_EndDirective endOp)
+{
+    ZSTD_outBuffer output = { dst, dstCapacity, *dstPos };
+    ZSTD_inBuffer  input  = { src, srcSize, *srcPos };
+    /* ZSTD_compress_generic() will check validity of dstPos and srcPos */
+    size_t const cErr = ZSTD_compress_generic(cctx, &output, &input, endOp);
+    *dstPos = output.pos;
+    *srcPos = input.pos;
+    return cErr;
 }
 
 
@@ -3401,89 +4006,59 @@ size_t ZSTD_compressStream(ZSTD_CStream* zcs, ZSTD_outBuffer* output, ZSTD_inBuf
 *   @return : amount of data remaining to flush */
 size_t ZSTD_flushStream(ZSTD_CStream* zcs, ZSTD_outBuffer* output)
 {
-    size_t srcSize = 0;
-    size_t sizeWritten = output->size - output->pos;
-    size_t const result = ZSTD_compressStream_generic(zcs,
-                                                     (char*)(output->dst) + output->pos, &sizeWritten,
-                                                     &srcSize, &srcSize, /* use a valid src address instead of NULL */
-                                                      zsf_flush);
-    output->pos += sizeWritten;
-    if (ZSTD_isError(result)) return result;
-    return zcs->outBuffContentSize - zcs->outBuffFlushedSize;   /* remaining to flush */
+    ZSTD_inBuffer input = { NULL, 0, 0 };
+    if (output->pos > output->size) return ERROR(GENERIC);
+    CHECK_F( ZSTD_compressStream_generic(zcs, output, &input, ZSTD_e_flush) );
+    return zcs->outBuffContentSize - zcs->outBuffFlushedSize;  /* remaining to flush */
 }
 
 
 size_t ZSTD_endStream(ZSTD_CStream* zcs, ZSTD_outBuffer* output)
 {
-    BYTE* const ostart = (BYTE*)(output->dst) + output->pos;
-    BYTE* const oend = (BYTE*)(output->dst) + output->size;
-    BYTE* op = ostart;
-
-    if (zcs->stage != zcss_final) {
-        /* flush whatever remains */
-        size_t srcSize = 0;
-        size_t sizeWritten = output->size - output->pos;
-        size_t const notEnded = ZSTD_compressStream_generic(zcs, ostart, &sizeWritten,
-                                     &srcSize /* use a valid src address instead of NULL */, &srcSize, zsf_end);
-        size_t const remainingToFlush = zcs->outBuffContentSize - zcs->outBuffFlushedSize;
-        op += sizeWritten;
-        if (remainingToFlush) {
-            output->pos += sizeWritten;
-            return remainingToFlush + ZSTD_BLOCKHEADERSIZE /* final empty block */ + (zcs->checksum * 4);
-        }
-        /* create epilogue */
-        zcs->stage = zcss_final;
-        zcs->outBuffContentSize = !notEnded ? 0 :
-            /* write epilogue, including final empty block, into outBuff */
-            ZSTD_compressEnd(zcs->cctx, zcs->outBuff, zcs->outBuffSize, NULL, 0);
-        if (ZSTD_isError(zcs->outBuffContentSize)) return zcs->outBuffContentSize;
-    }
-
-    /* flush epilogue */
-    {   size_t const toFlush = zcs->outBuffContentSize - zcs->outBuffFlushedSize;
-        size_t const flushed = ZSTD_limitCopy(op, oend-op, zcs->outBuff + zcs->outBuffFlushedSize, toFlush);
-        op += flushed;
-        zcs->outBuffFlushedSize += flushed;
-        output->pos += op-ostart;
-        if (toFlush==flushed) zcs->stage = zcss_init;  /* end reached */
-        return toFlush - flushed;
+    ZSTD_inBuffer input = { NULL, 0, 0 };
+    if (output->pos > output->size) return ERROR(GENERIC);
+    CHECK_F( ZSTD_compressStream_generic(zcs, output, &input, ZSTD_e_end) );
+    {   size_t const lastBlockSize = zcs->frameEnded ? 0 : ZSTD_BLOCKHEADERSIZE;
+        size_t const checksumSize = zcs->frameEnded ? 0 : zcs->appliedParams.fParams.checksumFlag * 4;
+        size_t const toFlush = zcs->outBuffContentSize - zcs->outBuffFlushedSize + lastBlockSize + checksumSize;
+        DEBUGLOG(5, "ZSTD_endStream : remaining to flush : %u",
+                (unsigned)toFlush);
+        return toFlush;
     }
 }
 
 
-
 /*-=====  Pre-defined compression levels  =====-*/
 
-#define ZSTD_DEFAULT_CLEVEL 1
 #define ZSTD_MAX_CLEVEL     22
 int ZSTD_maxCLevel(void) { return ZSTD_MAX_CLEVEL; }
 
 static const ZSTD_compressionParameters ZSTD_defaultCParameters[4][ZSTD_MAX_CLEVEL+1] = {
-{   /* "default" */
+{   /* "default" - guarantees a monotonically increasing memory budget */
     /* W,  C,  H,  S,  L, TL, strat */
     { 18, 12, 12,  1,  7, 16, ZSTD_fast    },  /* level  0 - never used */
     { 19, 13, 14,  1,  7, 16, ZSTD_fast    },  /* level  1 */
     { 19, 15, 16,  1,  6, 16, ZSTD_fast    },  /* level  2 */
-    { 20, 16, 17,  1,  5, 16, ZSTD_dfast   },  /* level  3.*/
-    { 20, 18, 18,  1,  5, 16, ZSTD_dfast   },  /* level  4.*/
-    { 20, 15, 18,  3,  5, 16, ZSTD_greedy  },  /* level  5 */
-    { 21, 16, 19,  2,  5, 16, ZSTD_lazy    },  /* level  6 */
-    { 21, 17, 20,  3,  5, 16, ZSTD_lazy    },  /* level  7 */
+    { 20, 16, 17,  1,  5, 16, ZSTD_dfast   },  /* level  3 */
+    { 20, 17, 18,  1,  5, 16, ZSTD_dfast   },  /* level  4 */
+    { 20, 17, 18,  2,  5, 16, ZSTD_greedy  },  /* level  5 */
+    { 21, 17, 19,  2,  5, 16, ZSTD_lazy    },  /* level  6 */
+    { 21, 18, 19,  3,  5, 16, ZSTD_lazy    },  /* level  7 */
     { 21, 18, 20,  3,  5, 16, ZSTD_lazy2   },  /* level  8 */
-    { 21, 20, 20,  3,  5, 16, ZSTD_lazy2   },  /* level  9 */
+    { 21, 19, 20,  3,  5, 16, ZSTD_lazy2   },  /* level  9 */
     { 21, 19, 21,  4,  5, 16, ZSTD_lazy2   },  /* level 10 */
     { 22, 20, 22,  4,  5, 16, ZSTD_lazy2   },  /* level 11 */
     { 22, 20, 22,  5,  5, 16, ZSTD_lazy2   },  /* level 12 */
     { 22, 21, 22,  5,  5, 16, ZSTD_lazy2   },  /* level 13 */
     { 22, 21, 22,  6,  5, 16, ZSTD_lazy2   },  /* level 14 */
-    { 22, 21, 21,  5,  5, 16, ZSTD_btlazy2 },  /* level 15 */
+    { 22, 21, 22,  5,  5, 16, ZSTD_btlazy2 },  /* level 15 */
     { 23, 22, 22,  5,  5, 16, ZSTD_btlazy2 },  /* level 16 */
-    { 23, 21, 22,  4,  5, 24, ZSTD_btopt   },  /* level 17 */
+    { 23, 22, 22,  4,  5, 24, ZSTD_btopt   },  /* level 17 */
     { 23, 22, 22,  5,  4, 32, ZSTD_btopt   },  /* level 18 */
     { 23, 23, 22,  6,  3, 48, ZSTD_btopt   },  /* level 19 */
-    { 25, 25, 23,  7,  3, 64, ZSTD_btopt2  },  /* level 20 */
-    { 26, 26, 23,  7,  3,256, ZSTD_btopt2  },  /* level 21 */
-    { 27, 27, 25,  9,  3,512, ZSTD_btopt2  },  /* level 22 */
+    { 25, 25, 23,  7,  3, 64, ZSTD_btultra },  /* level 20 */
+    { 26, 26, 24,  7,  3,256, ZSTD_btultra },  /* level 21 */
+    { 27, 27, 25,  9,  3,512, ZSTD_btultra },  /* level 22 */
 },
 {   /* for srcSize <= 256 KB */
     /* W,  C,  H,  S,  L,  T, strat */
@@ -3507,9 +4082,9 @@ static const ZSTD_compressionParameters ZSTD_defaultCParameters[4][ZSTD_MAX_CLEV
     { 18, 19, 18,  8,  3, 64, ZSTD_btopt   },  /* level 17.*/
     { 18, 19, 18,  9,  3,128, ZSTD_btopt   },  /* level 18.*/
     { 18, 19, 18, 10,  3,256, ZSTD_btopt   },  /* level 19.*/
-    { 18, 19, 18, 11,  3,512, ZSTD_btopt2  },  /* level 20.*/
-    { 18, 19, 18, 12,  3,512, ZSTD_btopt2  },  /* level 21.*/
-    { 18, 19, 18, 13,  3,512, ZSTD_btopt2  },  /* level 22.*/
+    { 18, 19, 18, 11,  3,512, ZSTD_btultra },  /* level 20.*/
+    { 18, 19, 18, 12,  3,512, ZSTD_btultra },  /* level 21.*/
+    { 18, 19, 18, 13,  3,512, ZSTD_btultra },  /* level 22.*/
 },
 {   /* for srcSize <= 128 KB */
     /* W,  C,  H,  S,  L,  T, strat */
@@ -3533,9 +4108,9 @@ static const ZSTD_compressionParameters ZSTD_defaultCParameters[4][ZSTD_MAX_CLEV
     { 17, 18, 17,  7,  3, 64, ZSTD_btopt   },  /* level 17.*/
     { 17, 18, 17,  7,  3,256, ZSTD_btopt   },  /* level 18.*/
     { 17, 18, 17,  8,  3,256, ZSTD_btopt   },  /* level 19.*/
-    { 17, 18, 17,  9,  3,256, ZSTD_btopt2  },  /* level 20.*/
-    { 17, 18, 17, 10,  3,256, ZSTD_btopt2  },  /* level 21.*/
-    { 17, 18, 17, 11,  3,512, ZSTD_btopt2  },  /* level 22.*/
+    { 17, 18, 17,  9,  3,256, ZSTD_btultra },  /* level 20.*/
+    { 17, 18, 17, 10,  3,256, ZSTD_btultra },  /* level 21.*/
+    { 17, 18, 17, 11,  3,512, ZSTD_btultra },  /* level 22.*/
 },
 {   /* for srcSize <= 16 KB */
     /* W,  C,  H,  S,  L,  T, strat */
@@ -3559,39 +4134,59 @@ static const ZSTD_compressionParameters ZSTD_defaultCParameters[4][ZSTD_MAX_CLEV
     { 14, 15, 15,  6,  3,128, ZSTD_btopt   },  /* level 17.*/
     { 14, 15, 15,  6,  3,256, ZSTD_btopt   },  /* level 18.*/
     { 14, 15, 15,  7,  3,256, ZSTD_btopt   },  /* level 19.*/
-    { 14, 15, 15,  8,  3,256, ZSTD_btopt2  },  /* level 20.*/
-    { 14, 15, 15,  9,  3,256, ZSTD_btopt2  },  /* level 21.*/
-    { 14, 15, 15, 10,  3,256, ZSTD_btopt2  },  /* level 22.*/
+    { 14, 15, 15,  8,  3,256, ZSTD_btultra },  /* level 20.*/
+    { 14, 15, 15,  9,  3,256, ZSTD_btultra },  /* level 21.*/
+    { 14, 15, 15, 10,  3,256, ZSTD_btultra },  /* level 22.*/
 },
 };
 
+#if defined(ZSTD_DEBUG) && (ZSTD_DEBUG>=1)
+/* This function just controls
+ * the monotonic memory budget increase of ZSTD_defaultCParameters[0].
+ * Run once, on first ZSTD_getCParams() usage, if ZSTD_DEBUG is enabled
+ */
+MEM_STATIC void ZSTD_check_compressionLevel_monotonicIncrease_memoryBudget(void)
+{
+    int level;
+    for (level=1; level<ZSTD_maxCLevel(); level++) {
+        ZSTD_compressionParameters const c1 = ZSTD_defaultCParameters[0][level];
+        ZSTD_compressionParameters const c2 = ZSTD_defaultCParameters[0][level+1];
+        assert(c1.windowLog <= c2.windowLog);
+#       define ZSTD_TABLECOST(h,c) ((1<<(h)) + (1<<(c)))
+        assert(ZSTD_TABLECOST(c1.hashLog, c1.chainLog) <= ZSTD_TABLECOST(c2.hashLog, c2.chainLog));
+    }
+}
+#endif
+
 /*! ZSTD_getCParams() :
 *   @return ZSTD_compressionParameters structure for a selected compression level, `srcSize` and `dictSize`.
 *   Size values are optional, provide 0 if not known or unused */
-ZSTD_compressionParameters ZSTD_getCParams(int compressionLevel, unsigned long long srcSize, size_t dictSize)
+ZSTD_compressionParameters ZSTD_getCParams(int compressionLevel, unsigned long long srcSizeHint, size_t dictSize)
 {
-    ZSTD_compressionParameters cp;
-    size_t const addedSize = srcSize ? 0 : 500;
-    U64 const rSize = srcSize+dictSize ? srcSize+dictSize+addedSize : (U64)-1;
+    size_t const addedSize = srcSizeHint ? 0 : 500;
+    U64 const rSize = srcSizeHint+dictSize ? srcSizeHint+dictSize+addedSize : (U64)-1;
     U32 const tableID = (rSize <= 256 KB) + (rSize <= 128 KB) + (rSize <= 16 KB);   /* intentional underflow for srcSizeHint == 0 */
-    if (compressionLevel <= 0) compressionLevel = ZSTD_DEFAULT_CLEVEL;   /* 0 == default; no negative compressionLevel yet */
-    if (compressionLevel > ZSTD_MAX_CLEVEL) compressionLevel = ZSTD_MAX_CLEVEL;
-    cp = ZSTD_defaultCParameters[tableID][compressionLevel];
-    if (MEM_32bits()) {   /* auto-correction, for 32-bits mode */
-        if (cp.windowLog > ZSTD_WINDOWLOG_MAX) cp.windowLog = ZSTD_WINDOWLOG_MAX;
-        if (cp.chainLog > ZSTD_CHAINLOG_MAX) cp.chainLog = ZSTD_CHAINLOG_MAX;
-        if (cp.hashLog > ZSTD_HASHLOG_MAX) cp.hashLog = ZSTD_HASHLOG_MAX;
+
+#if defined(ZSTD_DEBUG) && (ZSTD_DEBUG>=1)
+    static int g_monotonicTest = 1;
+    if (g_monotonicTest) {
+        ZSTD_check_compressionLevel_monotonicIncrease_memoryBudget();
+        g_monotonicTest=0;
     }
-    cp = ZSTD_adjustCParams(cp, srcSize, dictSize);
-    return cp;
+#endif
+
+    if (compressionLevel <= 0) compressionLevel = ZSTD_CLEVEL_DEFAULT;   /* 0 == default; no negative compressionLevel yet */
+    if (compressionLevel > ZSTD_MAX_CLEVEL) compressionLevel = ZSTD_MAX_CLEVEL;
+    { ZSTD_compressionParameters const cp = ZSTD_defaultCParameters[tableID][compressionLevel];
+      return ZSTD_adjustCParams_internal(cp, srcSizeHint, dictSize); }
 }
 
 /*! ZSTD_getParams() :
 *   same as ZSTD_getCParams(), but @return a `ZSTD_parameters` object (instead of `ZSTD_compressionParameters`).
 *   All fields of `ZSTD_frameParameters` are set to default (0) */
-ZSTD_parameters ZSTD_getParams(int compressionLevel, unsigned long long srcSize, size_t dictSize) {
+ZSTD_parameters ZSTD_getParams(int compressionLevel, unsigned long long srcSizeHint, size_t dictSize) {
     ZSTD_parameters params;
-    ZSTD_compressionParameters const cParams = ZSTD_getCParams(compressionLevel, srcSize, dictSize);
+    ZSTD_compressionParameters const cParams = ZSTD_getCParams(compressionLevel, srcSizeHint, dictSize);
     memset(&params, 0, sizeof(params));
     params.cParams = cParams;
     return params;
diff --git a/thirdparty/zstd/compress/zstd_opt.h b/thirdparty/zstd/compress/zstd_opt.h
index 5437611912..e8e98915ea 100644
--- a/thirdparty/zstd/compress/zstd_opt.h
+++ b/thirdparty/zstd/compress/zstd_opt.h
@@ -43,6 +43,7 @@ MEM_STATIC void ZSTD_rescaleFreqs(seqStore_t* ssPtr, const BYTE* src, size_t src
     if (ssPtr->litLengthSum == 0) {
         if (srcSize <= 1024) ssPtr->staticPrices = 1;
 
+        assert(ssPtr->litFreq!=NULL);
         for (u=0; u<=MaxLit; u++)
             ssPtr->litFreq[u] = 0;
         for (u=0; u<srcSize; u++)
@@ -201,6 +202,20 @@ MEM_STATIC void ZSTD_updatePrice(seqStore_t* seqStorePtr, U32 litLength, const B
     }
 
 
+/* function safe only for comparisons */
+MEM_STATIC U32 ZSTD_readMINMATCH(const void* memPtr, U32 length)
+{
+    switch (length)
+    {
+    default :
+    case 4 : return MEM_read32(memPtr);
+    case 3 : if (MEM_isLittleEndian())
+                return MEM_read32(memPtr)<<8;
+             else
+                return MEM_read32(memPtr)>>8;
+    }
+}
+
 
 /* Update hashTable3 up to ip (excluded)
    Assumption : always within prefix (i.e. not within extDict) */
@@ -234,12 +249,12 @@ static U32 ZSTD_insertBtAndGetAllMatches (
 {
     const BYTE* const base = zc->base;
     const U32 current = (U32)(ip-base);
-    const U32 hashLog = zc->params.cParams.hashLog;
+    const U32 hashLog = zc->appliedParams.cParams.hashLog;
     const size_t h  = ZSTD_hashPtr(ip, hashLog, mls);
     U32* const hashTable = zc->hashTable;
     U32 matchIndex  = hashTable[h];
     U32* const bt   = zc->chainTable;
-    const U32 btLog = zc->params.cParams.chainLog - 1;
+    const U32 btLog = zc->appliedParams.cParams.chainLog - 1;
     const U32 btMask= (1U << btLog) - 1;
     size_t commonLengthSmaller=0, commonLengthLarger=0;
     const BYTE* const dictBase = zc->dictBase;
@@ -267,7 +282,7 @@ static U32 ZSTD_insertBtAndGetAllMatches (
                 if (match[bestLength] == ip[bestLength]) currentMl = ZSTD_count(ip, match, iLimit);
             } else {
                 match = dictBase + matchIndex3;
-                if (MEM_readMINMATCH(match, MINMATCH) == MEM_readMINMATCH(ip, MINMATCH))    /* assumption : matchIndex3 <= dictLimit-4 (by table construction) */
+                if (ZSTD_readMINMATCH(match, MINMATCH) == ZSTD_readMINMATCH(ip, MINMATCH))    /* assumption : matchIndex3 <= dictLimit-4 (by table construction) */
                     currentMl = ZSTD_count_2segments(ip+MINMATCH, match+MINMATCH, iLimit, dictEnd, prefixStart) + MINMATCH;
             }
 
@@ -410,10 +425,10 @@ void ZSTD_compressBlock_opt_generic(ZSTD_CCtx* ctx,
     const BYTE* const base = ctx->base;
     const BYTE* const prefixStart = base + ctx->dictLimit;
 
-    const U32 maxSearches = 1U << ctx->params.cParams.searchLog;
-    const U32 sufficient_len = ctx->params.cParams.targetLength;
-    const U32 mls = ctx->params.cParams.searchLength;
-    const U32 minMatch = (ctx->params.cParams.searchLength == 3) ? 3 : 4;
+    const U32 maxSearches = 1U << ctx->appliedParams.cParams.searchLog;
+    const U32 sufficient_len = ctx->appliedParams.cParams.targetLength;
+    const U32 mls = ctx->appliedParams.cParams.searchLength;
+    const U32 minMatch = (ctx->appliedParams.cParams.searchLength == 3) ? 3 : 4;
 
     ZSTD_optimal_t* opt = seqStorePtr->priceTable;
     ZSTD_match_t* matches = seqStorePtr->matchTable;
@@ -439,7 +454,7 @@ void ZSTD_compressBlock_opt_generic(ZSTD_CCtx* ctx,
             for (i=(ip == anchor); i<last_i; i++) {
                 const S32 repCur = (i==ZSTD_REP_MOVE_OPT) ? (rep[0] - 1) : rep[i];
                 if ( (repCur > 0) && (repCur < (S32)(ip-prefixStart))
-                    && (MEM_readMINMATCH(ip, minMatch) == MEM_readMINMATCH(ip - repCur, minMatch))) {
+                    && (ZSTD_readMINMATCH(ip, minMatch) == ZSTD_readMINMATCH(ip - repCur, minMatch))) {
                     mlen = (U32)ZSTD_count(ip+minMatch, ip+minMatch-repCur, iend) + minMatch;
                     if (mlen > sufficient_len || mlen >= ZSTD_OPT_NUM) {
                         best_mlen = mlen; best_off = i; cur = 0; last_pos = 1;
@@ -524,7 +539,7 @@ void ZSTD_compressBlock_opt_generic(ZSTD_CCtx* ctx,
                 for (i=(opt[cur].mlen != 1); i<last_i; i++) {  /* check rep */
                     const S32 repCur = (i==ZSTD_REP_MOVE_OPT) ? (opt[cur].rep[0] - 1) : opt[cur].rep[i];
                     if ( (repCur > 0) && (repCur < (S32)(inr-prefixStart))
-                       && (MEM_readMINMATCH(inr, minMatch) == MEM_readMINMATCH(inr - repCur, minMatch))) {
+                       && (ZSTD_readMINMATCH(inr, minMatch) == ZSTD_readMINMATCH(inr - repCur, minMatch))) {
                        mlen = (U32)ZSTD_count(inr+minMatch, inr+minMatch - repCur, iend) + minMatch;
 
                        if (mlen > sufficient_len || cur + mlen >= ZSTD_OPT_NUM) {
@@ -663,10 +678,10 @@ void ZSTD_compressBlock_opt_extDict_generic(ZSTD_CCtx* ctx,
     const BYTE* const dictBase = ctx->dictBase;
     const BYTE* const dictEnd  = dictBase + dictLimit;
 
-    const U32 maxSearches = 1U << ctx->params.cParams.searchLog;
-    const U32 sufficient_len = ctx->params.cParams.targetLength;
-    const U32 mls = ctx->params.cParams.searchLength;
-    const U32 minMatch = (ctx->params.cParams.searchLength == 3) ? 3 : 4;
+    const U32 maxSearches = 1U << ctx->appliedParams.cParams.searchLog;
+    const U32 sufficient_len = ctx->appliedParams.cParams.targetLength;
+    const U32 mls = ctx->appliedParams.cParams.searchLength;
+    const U32 minMatch = (ctx->appliedParams.cParams.searchLength == 3) ? 3 : 4;
 
     ZSTD_optimal_t* opt = seqStorePtr->priceTable;
     ZSTD_match_t* matches = seqStorePtr->matchTable;
@@ -698,7 +713,7 @@ void ZSTD_compressBlock_opt_extDict_generic(ZSTD_CCtx* ctx,
                 const BYTE* const repMatch = repBase + repIndex;
                 if ( (repCur > 0 && repCur <= (S32)current)
                    && (((U32)((dictLimit-1) - repIndex) >= 3) & (repIndex>lowestIndex))  /* intentional overflow */
-                   && (MEM_readMINMATCH(ip, minMatch) == MEM_readMINMATCH(repMatch, minMatch)) ) {
+                   && (ZSTD_readMINMATCH(ip, minMatch) == ZSTD_readMINMATCH(repMatch, minMatch)) ) {
                     /* repcode detected we should take it */
                     const BYTE* const repEnd = repIndex < dictLimit ? dictEnd : iend;
                     mlen = (U32)ZSTD_count_2segments(ip+minMatch, repMatch+minMatch, iend, repEnd, prefixStart) + minMatch;
@@ -794,7 +809,7 @@ void ZSTD_compressBlock_opt_extDict_generic(ZSTD_CCtx* ctx,
                     const BYTE* const repMatch = repBase + repIndex;
                     if ( (repCur > 0 && repCur <= (S32)(current+cur))
                       && (((U32)((dictLimit-1) - repIndex) >= 3) & (repIndex>lowestIndex))  /* intentional overflow */
-                      && (MEM_readMINMATCH(inr, minMatch) == MEM_readMINMATCH(repMatch, minMatch)) ) {
+                      && (ZSTD_readMINMATCH(inr, minMatch) == ZSTD_readMINMATCH(repMatch, minMatch)) ) {
                         /* repcode detected */
                         const BYTE* const repEnd = repIndex < dictLimit ? dictEnd : iend;
                         mlen = (U32)ZSTD_count_2segments(inr+minMatch, repMatch+minMatch, iend, repEnd, prefixStart) + minMatch;
diff --git a/thirdparty/zstd/compress/zstdmt_compress.c b/thirdparty/zstd/compress/zstdmt_compress.c
index fc7f52a290..0cee01eacb 100644
--- a/thirdparty/zstd/compress/zstdmt_compress.c
+++ b/thirdparty/zstd/compress/zstdmt_compress.c
@@ -14,34 +14,31 @@
 
 /* ======   Compiler specifics   ====== */
 #if defined(_MSC_VER)
-#  pragma warning(disable : 4204)        /* disable: C4204: non-constant aggregate initializer */
+#  pragma warning(disable : 4204)   /* disable: C4204: non-constant aggregate initializer */
 #endif
 
 
 /* ======   Dependencies   ====== */
-#include <stdlib.h>   /* malloc */
-#include <string.h>   /* memcpy */
-#include "pool.h"     /* threadpool */
-#include "threading.h"  /* mutex */
-#include "zstd_internal.h"   /* MIN, ERROR, ZSTD_*, ZSTD_highbit32 */
+#include <string.h>      /* memcpy, memset */
+#include "pool.h"        /* threadpool */
+#include "threading.h"   /* mutex */
+#include "zstd_internal.h"  /* MIN, ERROR, ZSTD_*, ZSTD_highbit32 */
 #include "zstdmt_compress.h"
 
 
 /* ======   Debug   ====== */
-#if 0
+#if defined(ZSTD_DEBUG) && (ZSTD_DEBUG>=2)
 
 #  include <stdio.h>
 #  include <unistd.h>
 #  include <sys/times.h>
-   static unsigned g_debugLevel = 5;
-#  define DEBUGLOGRAW(l, ...) if (l<=g_debugLevel) { fprintf(stderr, __VA_ARGS__); }
-#  define DEBUGLOG(l, ...) if (l<=g_debugLevel) { fprintf(stderr, __FILE__ ": "); fprintf(stderr, __VA_ARGS__); fprintf(stderr, " \n"); }
+#  define DEBUGLOGRAW(l, ...) if (l<=ZSTD_DEBUG) { fprintf(stderr, __VA_ARGS__); }
 
-#  define DEBUG_PRINTHEX(l,p,n) { \
-    unsigned debug_u;                   \
-    for (debug_u=0; debug_u<(n); debug_u++)           \
+#  define DEBUG_PRINTHEX(l,p,n) {            \
+    unsigned debug_u;                        \
+    for (debug_u=0; debug_u<(n); debug_u++)  \
         DEBUGLOGRAW(l, "%02X ", ((const unsigned char*)(p))[debug_u]); \
-    DEBUGLOGRAW(l, " \n");       \
+    DEBUGLOGRAW(l, " \n");                   \
 }
 
 static unsigned long long GetCurrentClockTimeMicroseconds(void)
@@ -53,22 +50,22 @@ static unsigned long long GetCurrentClockTimeMicroseconds(void)
      return ((((unsigned long long)newTicks)*(1000000))/_ticksPerSecond); }
 }
 
-#define MUTEX_WAIT_TIME_DLEVEL 5
-#define PTHREAD_MUTEX_LOCK(mutex) \
-if (g_debugLevel>=MUTEX_WAIT_TIME_DLEVEL) { \
-    unsigned long long const beforeTime = GetCurrentClockTimeMicroseconds(); \
-    pthread_mutex_lock(mutex); \
-    {   unsigned long long const afterTime = GetCurrentClockTimeMicroseconds(); \
-        unsigned long long const elapsedTime = (afterTime-beforeTime); \
-        if (elapsedTime > 1000) {  /* or whatever threshold you like; I'm using 1 millisecond here */ \
-            DEBUGLOG(MUTEX_WAIT_TIME_DLEVEL, "Thread took %llu microseconds to acquire mutex %s \n", \
-               elapsedTime, #mutex); \
-    }   } \
-} else pthread_mutex_lock(mutex);
+#define MUTEX_WAIT_TIME_DLEVEL 6
+#define PTHREAD_MUTEX_LOCK(mutex) {               \
+    if (ZSTD_DEBUG>=MUTEX_WAIT_TIME_DLEVEL) {   \
+        unsigned long long const beforeTime = GetCurrentClockTimeMicroseconds(); \
+        pthread_mutex_lock(mutex);                \
+        {   unsigned long long const afterTime = GetCurrentClockTimeMicroseconds(); \
+            unsigned long long const elapsedTime = (afterTime-beforeTime); \
+            if (elapsedTime > 1000) {  /* or whatever threshold you like; I'm using 1 millisecond here */ \
+                DEBUGLOG(MUTEX_WAIT_TIME_DLEVEL, "Thread took %llu microseconds to acquire mutex %s \n", \
+                   elapsedTime, #mutex);          \
+        }   }                                     \
+    } else pthread_mutex_lock(mutex);             \
+}
 
 #else
 
-#  define DEBUGLOG(l, ...)      {}    /* disabled */
 #  define PTHREAD_MUTEX_LOCK(m) pthread_mutex_lock(m)
 #  define DEBUG_PRINTHEX(l,p,n) {}
 
@@ -87,16 +84,19 @@ static const buffer_t g_nullBuffer = { NULL, 0 };
 typedef struct ZSTDMT_bufferPool_s {
     unsigned totalBuffers;
     unsigned nbBuffers;
+    ZSTD_customMem cMem;
     buffer_t bTable[1];   /* variable size */
 } ZSTDMT_bufferPool;
 
-static ZSTDMT_bufferPool* ZSTDMT_createBufferPool(unsigned nbThreads)
+static ZSTDMT_bufferPool* ZSTDMT_createBufferPool(unsigned nbThreads, ZSTD_customMem cMem)
 {
     unsigned const maxNbBuffers = 2*nbThreads + 2;
-    ZSTDMT_bufferPool* const bufPool = (ZSTDMT_bufferPool*)calloc(1, sizeof(ZSTDMT_bufferPool) + (maxNbBuffers-1) * sizeof(buffer_t));
+    ZSTDMT_bufferPool* const bufPool = (ZSTDMT_bufferPool*)ZSTD_calloc(
+        sizeof(ZSTDMT_bufferPool) + (maxNbBuffers-1) * sizeof(buffer_t), cMem);
     if (bufPool==NULL) return NULL;
     bufPool->totalBuffers = maxNbBuffers;
     bufPool->nbBuffers = 0;
+    bufPool->cMem = cMem;
     return bufPool;
 }
 
@@ -105,23 +105,39 @@ static void ZSTDMT_freeBufferPool(ZSTDMT_bufferPool* bufPool)
     unsigned u;
     if (!bufPool) return;   /* compatibility with free on NULL */
     for (u=0; u<bufPool->totalBuffers; u++)
-        free(bufPool->bTable[u].start);
-    free(bufPool);
+        ZSTD_free(bufPool->bTable[u].start, bufPool->cMem);
+    ZSTD_free(bufPool, bufPool->cMem);
+}
+
+/* only works at initialization, not during compression */
+static size_t ZSTDMT_sizeof_bufferPool(ZSTDMT_bufferPool* bufPool)
+{
+    size_t const poolSize = sizeof(*bufPool)
+                            + (bufPool->totalBuffers - 1) * sizeof(buffer_t);
+    unsigned u;
+    size_t totalBufferSize = 0;
+    for (u=0; u<bufPool->totalBuffers; u++)
+        totalBufferSize += bufPool->bTable[u].size;
+
+    return poolSize + totalBufferSize;
 }
 
-/* assumption : invocation from main thread only ! */
+/** ZSTDMT_getBuffer() :
+ *  assumption : invocation from main thread only ! */
 static buffer_t ZSTDMT_getBuffer(ZSTDMT_bufferPool* pool, size_t bSize)
 {
     if (pool->nbBuffers) {   /* try to use an existing buffer */
         buffer_t const buf = pool->bTable[--(pool->nbBuffers)];
         size_t const availBufferSize = buf.size;
-        if ((availBufferSize >= bSize) & (availBufferSize <= 10*bSize))   /* large enough, but not too much */
+        if ((availBufferSize >= bSize) & (availBufferSize <= 10*bSize))
+            /* large enough, but not too much */
             return buf;
-        free(buf.start);   /* size conditions not respected : scratch this buffer and create a new one */
+        /* size conditions not respected : scratch this buffer, create new one */
+        ZSTD_free(buf.start, pool->cMem);
     }
     /* create new buffer */
     {   buffer_t buffer;
-        void* const start = malloc(bSize);
+        void* const start = ZSTD_malloc(bSize, pool->cMem);
         if (start==NULL) bSize = 0;
         buffer.start = start;   /* note : start can be NULL if malloc fails ! */
         buffer.size = bSize;
@@ -138,7 +154,7 @@ static void ZSTDMT_releaseBuffer(ZSTDMT_bufferPool* pool, buffer_t buf)
         return;
     }
     /* Reached bufferPool capacity (should not happen) */
-    free(buf.start);
+    ZSTD_free(buf.start, pool->cMem);
 }
 
 
@@ -147,6 +163,7 @@ static void ZSTDMT_releaseBuffer(ZSTDMT_bufferPool* pool, buffer_t buf)
 typedef struct {
     unsigned totalCCtx;
     unsigned availCCtx;
+    ZSTD_customMem cMem;
     ZSTD_CCtx* cctx[1];   /* variable size */
 } ZSTDMT_CCtxPool;
 
@@ -158,23 +175,40 @@ static void ZSTDMT_freeCCtxPool(ZSTDMT_CCtxPool* pool)
     unsigned u;
     for (u=0; u<pool->totalCCtx; u++)
         ZSTD_freeCCtx(pool->cctx[u]);  /* note : compatible with free on NULL */
-    free(pool);
+    ZSTD_free(pool, pool->cMem);
 }
 
 /* ZSTDMT_createCCtxPool() :
  * implies nbThreads >= 1 , checked by caller ZSTDMT_createCCtx() */
-static ZSTDMT_CCtxPool* ZSTDMT_createCCtxPool(unsigned nbThreads)
+static ZSTDMT_CCtxPool* ZSTDMT_createCCtxPool(unsigned nbThreads,
+                                              ZSTD_customMem cMem)
 {
-    ZSTDMT_CCtxPool* const cctxPool = (ZSTDMT_CCtxPool*) calloc(1, sizeof(ZSTDMT_CCtxPool) + (nbThreads-1)*sizeof(ZSTD_CCtx*));
+    ZSTDMT_CCtxPool* const cctxPool = (ZSTDMT_CCtxPool*) ZSTD_calloc(
+        sizeof(ZSTDMT_CCtxPool) + (nbThreads-1)*sizeof(ZSTD_CCtx*), cMem);
     if (!cctxPool) return NULL;
+    cctxPool->cMem = cMem;
     cctxPool->totalCCtx = nbThreads;
     cctxPool->availCCtx = 1;   /* at least one cctx for single-thread mode */
-    cctxPool->cctx[0] = ZSTD_createCCtx();
+    cctxPool->cctx[0] = ZSTD_createCCtx_advanced(cMem);
     if (!cctxPool->cctx[0]) { ZSTDMT_freeCCtxPool(cctxPool); return NULL; }
-    DEBUGLOG(1, "cctxPool created, with %u threads", nbThreads);
+    DEBUGLOG(3, "cctxPool created, with %u threads", nbThreads);
     return cctxPool;
 }
 
+/* only works during initialization phase, not during compression */
+static size_t ZSTDMT_sizeof_CCtxPool(ZSTDMT_CCtxPool* cctxPool)
+{
+    unsigned const nbThreads = cctxPool->totalCCtx;
+    size_t const poolSize = sizeof(*cctxPool)
+                            + (nbThreads-1)*sizeof(ZSTD_CCtx*);
+    unsigned u;
+    size_t totalCCtxSize = 0;
+    for (u=0; u<nbThreads; u++)
+        totalCCtxSize += ZSTD_sizeof_CCtx(cctxPool->cctx[u]);
+
+    return poolSize + totalCCtxSize;
+}
+
 static ZSTD_CCtx* ZSTDMT_getCCtx(ZSTDMT_CCtxPool* pool)
 {
     if (pool->availCCtx) {
@@ -218,7 +252,7 @@ typedef struct {
     pthread_mutex_t* jobCompleted_mutex;
     pthread_cond_t* jobCompleted_cond;
     ZSTD_parameters params;
-    ZSTD_CDict* cdict;
+    const ZSTD_CDict* cdict;
     unsigned long long fullFrameSize;
 } ZSTDMT_jobDescription;
 
@@ -228,11 +262,11 @@ void ZSTDMT_compressChunk(void* jobDescription)
     ZSTDMT_jobDescription* const job = (ZSTDMT_jobDescription*)jobDescription;
     const void* const src = (const char*)job->srcStart + job->dictSize;
     buffer_t const dstBuff = job->dstBuff;
-    DEBUGLOG(3, "job (first:%u) (last:%u) : dictSize %u, srcSize %u",
+    DEBUGLOG(5, "job (first:%u) (last:%u) : dictSize %u, srcSize %u",
                  job->firstChunk, job->lastChunk, (U32)job->dictSize, (U32)job->srcSize);
     if (job->cdict) {  /* should only happen for first segment */
         size_t const initError = ZSTD_compressBegin_usingCDict_advanced(job->cctx, job->cdict, job->params.fParams, job->fullFrameSize);
-        if (job->cdict) DEBUGLOG(3, "using CDict ");
+        DEBUGLOG(5, "using CDict");
         if (ZSTD_isError(initError)) { job->cSize = initError; goto _endJob; }
     } else {  /* srcStart points at reloaded section */
         if (!job->firstChunk) job->params.fParams.contentSizeFlag = 0;  /* ensure no srcSize control */
@@ -247,12 +281,12 @@ void ZSTDMT_compressChunk(void* jobDescription)
         ZSTD_invalidateRepCodes(job->cctx);
     }
 
-    DEBUGLOG(4, "Compressing : ");
+    DEBUGLOG(5, "Compressing : ");
     DEBUG_PRINTHEX(4, job->srcStart, 12);
     job->cSize = (job->lastChunk) ?
                  ZSTD_compressEnd     (job->cctx, dstBuff.start, dstBuff.size, src, job->srcSize) :
                  ZSTD_compressContinue(job->cctx, dstBuff.start, dstBuff.size, src, job->srcSize);
-    DEBUGLOG(3, "compressed %u bytes into %u bytes   (first:%u) (last:%u)",
+    DEBUGLOG(5, "compressed %u bytes into %u bytes   (first:%u) (last:%u)",
                 (unsigned)job->srcSize, (unsigned)job->cSize, job->firstChunk, job->lastChunk);
     DEBUGLOG(5, "dstBuff.size : %u ; => %s", (U32)dstBuff.size, ZSTD_getErrorName(job->cSize));
 
@@ -271,6 +305,7 @@ _endJob:
 
 struct ZSTDMT_CCtx_s {
     POOL_ctx* factory;
+    ZSTDMT_jobDescription* jobs;
     ZSTDMT_bufferPool* buffPool;
     ZSTDMT_CCtxPool* cctxPool;
     pthread_mutex_t jobCompleted_mutex;
@@ -292,50 +327,64 @@ struct ZSTDMT_CCtx_s {
     unsigned overlapRLog;
     unsigned long long frameContentSize;
     size_t sectionSize;
-    ZSTD_CDict* cdict;
-    ZSTD_CStream* cstream;
-    ZSTDMT_jobDescription jobs[1];   /* variable size (must lies at the end) */
+    ZSTD_customMem cMem;
+    ZSTD_CDict* cdictLocal;
+    const ZSTD_CDict* cdict;
 };
 
-ZSTDMT_CCtx *ZSTDMT_createCCtx(unsigned nbThreads)
+static ZSTDMT_jobDescription* ZSTDMT_allocJobsTable(U32* nbJobsPtr, ZSTD_customMem cMem)
 {
-    ZSTDMT_CCtx* cctx;
-    U32 const minNbJobs = nbThreads + 2;
-    U32 const nbJobsLog2 = ZSTD_highbit32(minNbJobs) + 1;
+    U32 const nbJobsLog2 = ZSTD_highbit32(*nbJobsPtr) + 1;
     U32 const nbJobs = 1 << nbJobsLog2;
-    DEBUGLOG(5, "nbThreads : %u  ; minNbJobs : %u ;  nbJobsLog2 : %u ;  nbJobs : %u  \n",
-            nbThreads, minNbJobs, nbJobsLog2, nbJobs);
+    *nbJobsPtr = nbJobs;
+    return (ZSTDMT_jobDescription*) ZSTD_calloc(
+                            nbJobs * sizeof(ZSTDMT_jobDescription), cMem);
+}
+
+ZSTDMT_CCtx* ZSTDMT_createCCtx_advanced(unsigned nbThreads, ZSTD_customMem cMem)
+{
+    ZSTDMT_CCtx* mtctx;
+    U32 nbJobs = nbThreads + 2;
+    DEBUGLOG(3, "ZSTDMT_createCCtx_advanced");
+
     if ((nbThreads < 1) | (nbThreads > ZSTDMT_NBTHREADS_MAX)) return NULL;
-    cctx = (ZSTDMT_CCtx*) calloc(1, sizeof(ZSTDMT_CCtx) + nbJobs*sizeof(ZSTDMT_jobDescription));
-    if (!cctx) return NULL;
-    cctx->nbThreads = nbThreads;
-    cctx->jobIDMask = nbJobs - 1;
-    cctx->allJobsCompleted = 1;
-    cctx->sectionSize = 0;
-    cctx->overlapRLog = 3;
-    cctx->factory = POOL_create(nbThreads, 1);
-    cctx->buffPool = ZSTDMT_createBufferPool(nbThreads);
-    cctx->cctxPool = ZSTDMT_createCCtxPool(nbThreads);
-    if (!cctx->factory | !cctx->buffPool | !cctx->cctxPool) {  /* one object was not created */
-        ZSTDMT_freeCCtx(cctx);
+    if ((cMem.customAlloc!=NULL) ^ (cMem.customFree!=NULL))
+        /* invalid custom allocator */
+        return NULL;
+
+    mtctx = (ZSTDMT_CCtx*) ZSTD_calloc(sizeof(ZSTDMT_CCtx), cMem);
+    if (!mtctx) return NULL;
+    mtctx->cMem = cMem;
+    mtctx->nbThreads = nbThreads;
+    mtctx->allJobsCompleted = 1;
+    mtctx->sectionSize = 0;
+    mtctx->overlapRLog = 3;
+    mtctx->factory = POOL_create(nbThreads, 1);
+    mtctx->jobs = ZSTDMT_allocJobsTable(&nbJobs, cMem);
+    mtctx->jobIDMask = nbJobs - 1;
+    mtctx->buffPool = ZSTDMT_createBufferPool(nbThreads, cMem);
+    mtctx->cctxPool = ZSTDMT_createCCtxPool(nbThreads, cMem);
+    if (!mtctx->factory | !mtctx->jobs | !mtctx->buffPool | !mtctx->cctxPool) {
+        ZSTDMT_freeCCtx(mtctx);
         return NULL;
     }
-    if (nbThreads==1) {
-        cctx->cstream = ZSTD_createCStream();
-        if (!cctx->cstream) {
-            ZSTDMT_freeCCtx(cctx); return NULL;
-    }   }
-    pthread_mutex_init(&cctx->jobCompleted_mutex, NULL);   /* Todo : check init function return */
-    pthread_cond_init(&cctx->jobCompleted_cond, NULL);
-    DEBUGLOG(4, "mt_cctx created, for %u threads \n", nbThreads);
-    return cctx;
+    pthread_mutex_init(&mtctx->jobCompleted_mutex, NULL);   /* Todo : check init function return */
+    pthread_cond_init(&mtctx->jobCompleted_cond, NULL);
+    DEBUGLOG(3, "mt_cctx created, for %u threads", nbThreads);
+    return mtctx;
+}
+
+ZSTDMT_CCtx* ZSTDMT_createCCtx(unsigned nbThreads)
+{
+    return ZSTDMT_createCCtx_advanced(nbThreads, ZSTD_defaultCMem);
 }
 
 /* ZSTDMT_releaseAllJobResources() :
- * Ensure all workers are killed first. */
+ * note : ensure all workers are killed first ! */
 static void ZSTDMT_releaseAllJobResources(ZSTDMT_CCtx* mtctx)
 {
     unsigned jobID;
+    DEBUGLOG(3, "ZSTDMT_releaseAllJobResources");
     for (jobID=0; jobID <= mtctx->jobIDMask; jobID++) {
         ZSTDMT_releaseBuffer(mtctx->buffPool, mtctx->jobs[jobID].dstBuff);
         mtctx->jobs[jobID].dstBuff = g_nullBuffer;
@@ -356,15 +405,26 @@ size_t ZSTDMT_freeCCtx(ZSTDMT_CCtx* mtctx)
     POOL_free(mtctx->factory);
     if (!mtctx->allJobsCompleted) ZSTDMT_releaseAllJobResources(mtctx); /* stop workers first */
     ZSTDMT_freeBufferPool(mtctx->buffPool);  /* release job resources into pools first */
+    ZSTD_free(mtctx->jobs, mtctx->cMem);
     ZSTDMT_freeCCtxPool(mtctx->cctxPool);
-    ZSTD_freeCDict(mtctx->cdict);
-    ZSTD_freeCStream(mtctx->cstream);
+    ZSTD_freeCDict(mtctx->cdictLocal);
     pthread_mutex_destroy(&mtctx->jobCompleted_mutex);
     pthread_cond_destroy(&mtctx->jobCompleted_cond);
-    free(mtctx);
+    ZSTD_free(mtctx, mtctx->cMem);
     return 0;
 }
 
+size_t ZSTDMT_sizeof_CCtx(ZSTDMT_CCtx* mtctx)
+{
+    if (mtctx == NULL) return 0;   /* supports sizeof NULL */
+    return sizeof(*mtctx)
+        + POOL_sizeof(mtctx->factory)
+        + ZSTDMT_sizeof_bufferPool(mtctx->buffPool)
+        + (mtctx->jobIDMask+1) * sizeof(ZSTDMT_jobDescription)
+        + ZSTDMT_sizeof_CCtxPool(mtctx->cctxPool)
+        + ZSTD_sizeof_CDict(mtctx->cdictLocal);
+}
+
 size_t ZSTDMT_setMTCtxParameter(ZSTDMT_CCtx* mtctx, ZSDTMT_parameter parameter, unsigned value)
 {
     switch(parameter)
@@ -373,7 +433,7 @@ size_t ZSTDMT_setMTCtxParameter(ZSTDMT_CCtx* mtctx, ZSDTMT_parameter parameter,
         mtctx->sectionSize = value;
         return 0;
     case ZSTDMT_p_overlapSectionLog :
-    DEBUGLOG(4, "ZSTDMT_p_overlapSectionLog : %u", value);
+        DEBUGLOG(5, "ZSTDMT_p_overlapSectionLog : %u", value);
         mtctx->overlapRLog = (value >= 9) ? 0 : 9 - value;
         return 0;
     default :
@@ -386,31 +446,49 @@ size_t ZSTDMT_setMTCtxParameter(ZSTDMT_CCtx* mtctx, ZSDTMT_parameter parameter,
 /* =====   Multi-threaded compression   ===== */
 /* ------------------------------------------ */
 
-size_t ZSTDMT_compressCCtx(ZSTDMT_CCtx* mtctx,
+static unsigned computeNbChunks(size_t srcSize, unsigned windowLog, unsigned nbThreads) {
+    size_t const chunkSizeTarget = (size_t)1 << (windowLog + 2);
+    size_t const chunkMaxSize = chunkSizeTarget << 2;
+    size_t const passSizeMax = chunkMaxSize * nbThreads;
+    unsigned const multiplier = (unsigned)(srcSize / passSizeMax) + 1;
+    unsigned const nbChunksLarge = multiplier * nbThreads;
+    unsigned const nbChunksMax = (unsigned)(srcSize / chunkSizeTarget) + 1;
+    unsigned const nbChunksSmall = MIN(nbChunksMax, nbThreads);
+    return (multiplier>1) ? nbChunksLarge : nbChunksSmall;
+}
+
+
+size_t ZSTDMT_compress_advanced(ZSTDMT_CCtx* mtctx,
                            void* dst, size_t dstCapacity,
                      const void* src, size_t srcSize,
-                           int compressionLevel)
+                     const ZSTD_CDict* cdict,
+                           ZSTD_parameters const params,
+                           unsigned overlapRLog)
 {
-    ZSTD_parameters params = ZSTD_getParams(compressionLevel, srcSize, 0);
-    U32 const overlapLog = (compressionLevel >= ZSTD_maxCLevel()) ? 0 : 3;
-    size_t const overlapSize = (size_t)1 << (params.cParams.windowLog - overlapLog);
-    size_t const chunkTargetSize = (size_t)1 << (params.cParams.windowLog + 2);
-    unsigned const nbChunksMax = (unsigned)(srcSize / chunkTargetSize) + 1;
-    unsigned nbChunks = MIN(nbChunksMax, mtctx->nbThreads);
+    size_t const overlapSize = (overlapRLog>=9) ? 0 : (size_t)1 << (params.cParams.windowLog - overlapRLog);
+    unsigned nbChunks = computeNbChunks(srcSize, params.cParams.windowLog, mtctx->nbThreads);
     size_t const proposedChunkSize = (srcSize + (nbChunks-1)) / nbChunks;
-    size_t const avgChunkSize = ((proposedChunkSize & 0x1FFFF) < 0xFFFF) ? proposedChunkSize + 0xFFFF : proposedChunkSize;   /* avoid too small last block */
-    size_t remainingSrcSize = srcSize;
+    size_t const avgChunkSize = ((proposedChunkSize & 0x1FFFF) < 0x7FFF) ? proposedChunkSize + 0xFFFF : proposedChunkSize;   /* avoid too small last block */
     const char* const srcStart = (const char*)src;
+    size_t remainingSrcSize = srcSize;
     unsigned const compressWithinDst = (dstCapacity >= ZSTD_compressBound(srcSize)) ? nbChunks : (unsigned)(dstCapacity / ZSTD_compressBound(avgChunkSize));  /* presumes avgChunkSize >= 256 KB, which should be the case */
     size_t frameStartPos = 0, dstBufferPos = 0;
 
-    DEBUGLOG(3, "windowLog : %2u => chunkTargetSize : %u bytes  ", params.cParams.windowLog, (U32)chunkTargetSize);
-    DEBUGLOG(2, "nbChunks  : %2u   (chunkSize : %u bytes)   ", nbChunks, (U32)avgChunkSize);
-    params.fParams.contentSizeFlag = 1;
-
+    DEBUGLOG(4, "nbChunks  : %2u   (chunkSize : %u bytes)   ", nbChunks, (U32)avgChunkSize);
     if (nbChunks==1) {   /* fallback to single-thread mode */
         ZSTD_CCtx* const cctx = mtctx->cctxPool->cctx[0];
-        return ZSTD_compressCCtx(cctx, dst, dstCapacity, src, srcSize, compressionLevel);
+        if (cdict) return ZSTD_compress_usingCDict_advanced(cctx, dst, dstCapacity, src, srcSize, cdict, params.fParams);
+        return ZSTD_compress_advanced(cctx, dst, dstCapacity, src, srcSize, NULL, 0, params);
+    }
+    assert(avgChunkSize >= 256 KB);  /* condition for ZSTD_compressBound(A) + ZSTD_compressBound(B) <= ZSTD_compressBound(A+B), which is useful to avoid allocating extra buffers */
+
+    if (nbChunks > mtctx->jobIDMask+1) {  /* enlarge job table */
+        U32 nbJobs = nbChunks;
+        ZSTD_free(mtctx->jobs, mtctx->cMem);
+        mtctx->jobIDMask = 0;
+        mtctx->jobs = ZSTDMT_allocJobsTable(&nbJobs, mtctx->cMem);
+        if (mtctx->jobs==NULL) return ERROR(memory_allocation);
+        mtctx->jobIDMask = nbJobs - 1;
     }
 
     {   unsigned u;
@@ -425,15 +503,18 @@ size_t ZSTDMT_compressCCtx(ZSTDMT_CCtx* mtctx,
             if ((cctx==NULL) || (dstBuffer.start==NULL)) {
                 mtctx->jobs[u].cSize = ERROR(memory_allocation);   /* job result */
                 mtctx->jobs[u].jobCompleted = 1;
-                nbChunks = u+1;
+                nbChunks = u+1;   /* only wait and free u jobs, instead of initially expected nbChunks ones */
                 break;   /* let's wait for previous jobs to complete, but don't start new ones */
             }
 
             mtctx->jobs[u].srcStart = srcStart + frameStartPos - dictSize;
             mtctx->jobs[u].dictSize = dictSize;
             mtctx->jobs[u].srcSize = chunkSize;
+            mtctx->jobs[u].cdict = mtctx->nextJobID==0 ? cdict : NULL;
             mtctx->jobs[u].fullFrameSize = srcSize;
             mtctx->jobs[u].params = params;
+            /* do not calculate checksum within sections, but write it in header for first section */
+            if (u!=0) mtctx->jobs[u].params.fParams.checksumFlag = 0;
             mtctx->jobs[u].dstBuff = dstBuffer;
             mtctx->jobs[u].cctx = cctx;
             mtctx->jobs[u].firstChunk = (u==0);
@@ -442,27 +523,27 @@ size_t ZSTDMT_compressCCtx(ZSTDMT_CCtx* mtctx,
             mtctx->jobs[u].jobCompleted_mutex = &mtctx->jobCompleted_mutex;
             mtctx->jobs[u].jobCompleted_cond = &mtctx->jobCompleted_cond;
 
-            DEBUGLOG(3, "posting job %u   (%u bytes)", u, (U32)chunkSize);
-            DEBUG_PRINTHEX(3, mtctx->jobs[u].srcStart, 12);
+            DEBUGLOG(5, "posting job %u   (%u bytes)", u, (U32)chunkSize);
+            DEBUG_PRINTHEX(6, mtctx->jobs[u].srcStart, 12);
             POOL_add(mtctx->factory, ZSTDMT_compressChunk, &mtctx->jobs[u]);
 
             frameStartPos += chunkSize;
             dstBufferPos += dstBufferCapacity;
             remainingSrcSize -= chunkSize;
     }   }
-    /* note : since nbChunks <= nbThreads, all jobs should be running immediately in parallel */
 
+    /* collect result */
     {   unsigned chunkID;
         size_t error = 0, dstPos = 0;
         for (chunkID=0; chunkID<nbChunks; chunkID++) {
-            DEBUGLOG(3, "waiting for chunk %u ", chunkID);
+            DEBUGLOG(5, "waiting for chunk %u ", chunkID);
             PTHREAD_MUTEX_LOCK(&mtctx->jobCompleted_mutex);
             while (mtctx->jobs[chunkID].jobCompleted==0) {
-                DEBUGLOG(4, "waiting for jobCompleted signal from chunk %u", chunkID);
+                DEBUGLOG(5, "waiting for jobCompleted signal from chunk %u", chunkID);
                 pthread_cond_wait(&mtctx->jobCompleted_cond, &mtctx->jobCompleted_mutex);
             }
             pthread_mutex_unlock(&mtctx->jobCompleted_mutex);
-            DEBUGLOG(3, "ready to write chunk %u ", chunkID);
+            DEBUGLOG(5, "ready to write chunk %u ", chunkID);
 
             ZSTDMT_releaseCCtx(mtctx->cctxPool, mtctx->jobs[chunkID].cctx);
             mtctx->jobs[chunkID].cctx = NULL;
@@ -470,20 +551,33 @@ size_t ZSTDMT_compressCCtx(ZSTDMT_CCtx* mtctx,
             {   size_t const cSize = mtctx->jobs[chunkID].cSize;
                 if (ZSTD_isError(cSize)) error = cSize;
                 if ((!error) && (dstPos + cSize > dstCapacity)) error = ERROR(dstSize_tooSmall);
-                if (chunkID) {   /* note : chunk 0 is already written directly into dst */
+                if (chunkID) {   /* note : chunk 0 is written directly at dst, which is correct position */
                     if (!error)
-                        memmove((char*)dst + dstPos, mtctx->jobs[chunkID].dstBuff.start, cSize);  /* may overlap if chunk decompressed within dst */
-                    if (chunkID >= compressWithinDst)   /* otherwise, it decompresses within dst */
+                        memmove((char*)dst + dstPos, mtctx->jobs[chunkID].dstBuff.start, cSize);  /* may overlap when chunk compressed within dst */
+                    if (chunkID >= compressWithinDst) {  /* chunk compressed into its own buffer, which must be released */
+                        DEBUGLOG(5, "releasing buffer %u>=%u", chunkID, compressWithinDst);
                         ZSTDMT_releaseBuffer(mtctx->buffPool, mtctx->jobs[chunkID].dstBuff);
+                    }
                     mtctx->jobs[chunkID].dstBuff = g_nullBuffer;
                 }
                 dstPos += cSize ;
             }
         }
-        if (!error) DEBUGLOG(3, "compressed size : %u  ", (U32)dstPos);
+        if (!error) DEBUGLOG(4, "compressed size : %u  ", (U32)dstPos);
         return error ? error : dstPos;
     }
+}
+
 
+size_t ZSTDMT_compressCCtx(ZSTDMT_CCtx* mtctx,
+                           void* dst, size_t dstCapacity,
+                     const void* src, size_t srcSize,
+                           int compressionLevel)
+{
+    U32 const overlapRLog = (compressionLevel >= ZSTD_maxCLevel()) ? 0 : 3;
+    ZSTD_parameters params = ZSTD_getParams(compressionLevel, srcSize, 0);
+    params.fParams.contentSizeFlag = 1;
+    return ZSTDMT_compress_advanced(mtctx, dst, dstCapacity, src, srcSize, NULL, params, overlapRLog);
 }
 
 
@@ -491,12 +585,14 @@ size_t ZSTDMT_compressCCtx(ZSTDMT_CCtx* mtctx,
 /* =======      Streaming API     ======= */
 /* ====================================== */
 
-static void ZSTDMT_waitForAllJobsCompleted(ZSTDMT_CCtx* zcs) {
+static void ZSTDMT_waitForAllJobsCompleted(ZSTDMT_CCtx* zcs)
+{
+    DEBUGLOG(4, "ZSTDMT_waitForAllJobsCompleted");
     while (zcs->doneJobID < zcs->nextJobID) {
         unsigned const jobID = zcs->doneJobID & zcs->jobIDMask;
         PTHREAD_MUTEX_LOCK(&zcs->jobCompleted_mutex);
         while (zcs->jobs[jobID].jobCompleted==0) {
-            DEBUGLOG(4, "waiting for jobCompleted signal from chunk %u", zcs->doneJobID);   /* we want to block when waiting for data to flush */
+            DEBUGLOG(5, "waiting for jobCompleted signal from chunk %u", zcs->doneJobID);   /* we want to block when waiting for data to flush */
             pthread_cond_wait(&zcs->jobCompleted_cond, &zcs->jobCompleted_mutex);
         }
         pthread_mutex_unlock(&zcs->jobCompleted_mutex);
@@ -505,33 +601,54 @@ static void ZSTDMT_waitForAllJobsCompleted(ZSTDMT_CCtx* zcs) {
 }
 
 
-static size_t ZSTDMT_initCStream_internal(ZSTDMT_CCtx* zcs,
-                                    const void* dict, size_t dictSize, unsigned updateDict,
-                                    ZSTD_parameters params, unsigned long long pledgedSrcSize)
+/** ZSTDMT_initCStream_internal() :
+ *  internal usage only */
+size_t ZSTDMT_initCStream_internal(ZSTDMT_CCtx* zcs,
+                    const void* dict, size_t dictSize, const ZSTD_CDict* cdict,
+                    ZSTD_parameters params, unsigned long long pledgedSrcSize)
 {
-    ZSTD_customMem const cmem = { NULL, NULL, NULL };
-    DEBUGLOG(3, "Started new compression, with windowLog : %u", params.cParams.windowLog);
-    if (zcs->nbThreads==1) return ZSTD_initCStream_advanced(zcs->cstream, dict, dictSize, params, pledgedSrcSize);
-    if (zcs->allJobsCompleted == 0) {   /* previous job not correctly finished */
+    DEBUGLOG(4, "ZSTDMT_initCStream_internal");
+    /* params are supposed to be fully validated at this point */
+    assert(!ZSTD_isError(ZSTD_checkCParams(params.cParams)));
+    assert(!((dict) && (cdict)));  /* either dict or cdict, not both */
+
+    if (zcs->nbThreads==1) {
+        DEBUGLOG(4, "single thread mode");
+        return ZSTD_initCStream_internal(zcs->cctxPool->cctx[0],
+                                dict, dictSize, cdict,
+                                params, pledgedSrcSize);
+    }
+
+    if (zcs->allJobsCompleted == 0) {   /* previous compression not correctly finished */
         ZSTDMT_waitForAllJobsCompleted(zcs);
         ZSTDMT_releaseAllJobResources(zcs);
         zcs->allJobsCompleted = 1;
     }
+
     zcs->params = params;
-    if (updateDict) {
-        ZSTD_freeCDict(zcs->cdict); zcs->cdict = NULL;
-        if (dict && dictSize) {
-            zcs->cdict = ZSTD_createCDict_advanced(dict, dictSize, 0, params.cParams, cmem);
-            if (zcs->cdict == NULL) return ERROR(memory_allocation);
-    }   }
     zcs->frameContentSize = pledgedSrcSize;
+    if (dict) {
+        DEBUGLOG(4,"cdictLocal: %08X", (U32)(size_t)zcs->cdictLocal);
+        ZSTD_freeCDict(zcs->cdictLocal);
+        zcs->cdictLocal = ZSTD_createCDict_advanced(dict, dictSize,
+                                                    0 /* byRef */, ZSTD_dm_auto,   /* note : a loadPrefix becomes an internal CDict */
+                                                    params.cParams, zcs->cMem);
+        zcs->cdict = zcs->cdictLocal;
+        if (zcs->cdictLocal == NULL) return ERROR(memory_allocation);
+    } else {
+        DEBUGLOG(4,"cdictLocal: %08X", (U32)(size_t)zcs->cdictLocal);
+        ZSTD_freeCDict(zcs->cdictLocal);
+        zcs->cdictLocal = NULL;
+        zcs->cdict = cdict;
+    }
+
     zcs->targetDictSize = (zcs->overlapRLog>=9) ? 0 : (size_t)1 << (zcs->params.cParams.windowLog - zcs->overlapRLog);
     DEBUGLOG(4, "overlapRLog : %u ", zcs->overlapRLog);
-    DEBUGLOG(3, "overlap Size : %u KB", (U32)(zcs->targetDictSize>>10));
+    DEBUGLOG(4, "overlap Size : %u KB", (U32)(zcs->targetDictSize>>10));
     zcs->targetSectionSize = zcs->sectionSize ? zcs->sectionSize : (size_t)1 << (zcs->params.cParams.windowLog + 2);
     zcs->targetSectionSize = MAX(ZSTDMT_SECTION_SIZE_MIN, zcs->targetSectionSize);
     zcs->targetSectionSize = MAX(zcs->targetDictSize, zcs->targetSectionSize);
-    DEBUGLOG(3, "Section Size : %u KB", (U32)(zcs->targetSectionSize>>10));
+    DEBUGLOG(4, "Section Size : %u KB", (U32)(zcs->targetSectionSize>>10));
     zcs->marginSize = zcs->targetSectionSize >> 2;
     zcs->inBuffSize = zcs->targetDictSize + zcs->targetSectionSize + zcs->marginSize;
     zcs->inBuff.buffer = ZSTDMT_getBuffer(zcs->buffPool, zcs->inBuffSize);
@@ -546,24 +663,39 @@ static size_t ZSTDMT_initCStream_internal(ZSTDMT_CCtx* zcs,
     return 0;
 }
 
-size_t ZSTDMT_initCStream_advanced(ZSTDMT_CCtx* zcs,
+size_t ZSTDMT_initCStream_advanced(ZSTDMT_CCtx* mtctx,
                                 const void* dict, size_t dictSize,
                                 ZSTD_parameters params, unsigned long long pledgedSrcSize)
 {
-    return ZSTDMT_initCStream_internal(zcs, dict, dictSize, 1, params, pledgedSrcSize);
+    DEBUGLOG(5, "ZSTDMT_initCStream_advanced");
+    return ZSTDMT_initCStream_internal(mtctx, dict, dictSize, NULL, params, pledgedSrcSize);
 }
 
+size_t ZSTDMT_initCStream_usingCDict(ZSTDMT_CCtx* mtctx,
+                               const ZSTD_CDict* cdict,
+                                     ZSTD_frameParameters fParams,
+                                     unsigned long long pledgedSrcSize)
+{
+    ZSTD_parameters params = ZSTD_getParamsFromCDict(cdict);
+    if (cdict==NULL) return ERROR(dictionary_wrong);   /* method incompatible with NULL cdict */
+    params.fParams = fParams;
+    return ZSTDMT_initCStream_internal(mtctx, NULL, 0 /*dictSize*/, cdict,
+                                        params, pledgedSrcSize);
+}
+
+
 /* ZSTDMT_resetCStream() :
  * pledgedSrcSize is optional and can be zero == unknown */
 size_t ZSTDMT_resetCStream(ZSTDMT_CCtx* zcs, unsigned long long pledgedSrcSize)
 {
-    if (zcs->nbThreads==1) return ZSTD_resetCStream(zcs->cstream, pledgedSrcSize);
+    if (zcs->nbThreads==1)
+        return ZSTD_resetCStream(zcs->cctxPool->cctx[0], pledgedSrcSize);
     return ZSTDMT_initCStream_internal(zcs, NULL, 0, 0, zcs->params, pledgedSrcSize);
 }
 
 size_t ZSTDMT_initCStream(ZSTDMT_CCtx* zcs, int compressionLevel) {
     ZSTD_parameters const params = ZSTD_getParams(compressionLevel, 0, 0);
-    return ZSTDMT_initCStream_internal(zcs, NULL, 0, 1, params, 0);
+    return ZSTDMT_initCStream_internal(zcs, NULL, 0, NULL, params, 0);
 }
 
 
@@ -582,13 +714,16 @@ static size_t ZSTDMT_createCompressionJob(ZSTDMT_CCtx* zcs, size_t srcSize, unsi
         return ERROR(memory_allocation);
     }
 
-    DEBUGLOG(4, "preparing job %u to compress %u bytes with %u preload ", zcs->nextJobID, (U32)srcSize, (U32)zcs->dictSize);
+    DEBUGLOG(4, "preparing job %u to compress %u bytes with %u preload ",
+                zcs->nextJobID, (U32)srcSize, (U32)zcs->dictSize);
     zcs->jobs[jobID].src = zcs->inBuff.buffer;
     zcs->jobs[jobID].srcStart = zcs->inBuff.buffer.start;
     zcs->jobs[jobID].srcSize = srcSize;
-    zcs->jobs[jobID].dictSize = zcs->dictSize;   /* note : zcs->inBuff.filled is presumed >= srcSize + dictSize */
+    zcs->jobs[jobID].dictSize = zcs->dictSize;
+    assert(zcs->inBuff.filled >= srcSize + zcs->dictSize);
     zcs->jobs[jobID].params = zcs->params;
-    if (zcs->nextJobID) zcs->jobs[jobID].params.fParams.checksumFlag = 0;  /* do not calculate checksum within sections, just keep it in header for first section */
+    /* do not calculate checksum within sections, but write it in header for first section */
+    if (zcs->nextJobID) zcs->jobs[jobID].params.fParams.checksumFlag = 0;
     zcs->jobs[jobID].cdict = zcs->nextJobID==0 ? zcs->cdict : NULL;
     zcs->jobs[jobID].fullFrameSize = zcs->frameContentSize;
     zcs->jobs[jobID].dstBuff = dstBuffer;
@@ -603,6 +738,7 @@ static size_t ZSTDMT_createCompressionJob(ZSTDMT_CCtx* zcs, size_t srcSize, unsi
     /* get a new buffer for next input */
     if (!endFrame) {
         size_t const newDictSize = MIN(srcSize + zcs->dictSize, zcs->targetDictSize);
+        DEBUGLOG(5, "ZSTDMT_createCompressionJob::endFrame = %u", endFrame);
         zcs->inBuff.buffer = ZSTDMT_getBuffer(zcs->buffPool, zcs->inBuffSize);
         if (zcs->inBuff.buffer.start == NULL) {   /* not enough memory to allocate next input buffer */
             zcs->jobs[jobID].jobCompleted = 1;
@@ -611,22 +747,33 @@ static size_t ZSTDMT_createCompressionJob(ZSTDMT_CCtx* zcs, size_t srcSize, unsi
             ZSTDMT_releaseAllJobResources(zcs);
             return ERROR(memory_allocation);
         }
-        DEBUGLOG(5, "inBuff filled to %u", (U32)zcs->inBuff.filled);
+        DEBUGLOG(5, "inBuff currently filled to %u", (U32)zcs->inBuff.filled);
         zcs->inBuff.filled -= srcSize + zcs->dictSize - newDictSize;
-        DEBUGLOG(5, "new job : filled to %u, with %u dict and %u src", (U32)zcs->inBuff.filled, (U32)newDictSize, (U32)(zcs->inBuff.filled - newDictSize));
-        memmove(zcs->inBuff.buffer.start, (const char*)zcs->jobs[jobID].srcStart + zcs->dictSize + srcSize - newDictSize, zcs->inBuff.filled);
+        DEBUGLOG(5, "new job : inBuff filled to %u, with %u dict and %u src",
+                    (U32)zcs->inBuff.filled, (U32)newDictSize,
+                    (U32)(zcs->inBuff.filled - newDictSize));
+        memmove(zcs->inBuff.buffer.start,
+            (const char*)zcs->jobs[jobID].srcStart + zcs->dictSize + srcSize - newDictSize,
+            zcs->inBuff.filled);
         DEBUGLOG(5, "new inBuff pre-filled");
         zcs->dictSize = newDictSize;
-    } else {
+    } else {   /* if (endFrame==1) */
+        DEBUGLOG(5, "ZSTDMT_createCompressionJob::endFrame = %u", endFrame);
         zcs->inBuff.buffer = g_nullBuffer;
         zcs->inBuff.filled = 0;
         zcs->dictSize = 0;
         zcs->frameEnded = 1;
         if (zcs->nextJobID == 0)
-            zcs->params.fParams.checksumFlag = 0;   /* single chunk : checksum is calculated directly within worker thread */
+            /* single chunk exception : checksum is calculated directly within worker thread */
+            zcs->params.fParams.checksumFlag = 0;
     }
 
-    DEBUGLOG(3, "posting job %u : %u bytes  (end:%u) (note : doneJob = %u=>%u)", zcs->nextJobID, (U32)zcs->jobs[jobID].srcSize, zcs->jobs[jobID].lastChunk, zcs->doneJobID, zcs->doneJobID & zcs->jobIDMask);
+    DEBUGLOG(4, "posting job %u : %u bytes  (end:%u) (note : doneJob = %u=>%u)",
+                zcs->nextJobID,
+                (U32)zcs->jobs[jobID].srcSize,
+                zcs->jobs[jobID].lastChunk,
+                zcs->doneJobID,
+                zcs->doneJobID & zcs->jobIDMask);
     POOL_add(zcs->factory, ZSTDMT_compressChunk, &zcs->jobs[jobID]);   /* this call is blocking when thread worker pool is exhausted */
     zcs->nextJobID++;
     return 0;
@@ -664,7 +811,7 @@ static size_t ZSTDMT_flushNextJob(ZSTDMT_CCtx* zcs, ZSTD_outBuffer* output, unsi
                 XXH64_update(&zcs->xxhState, (const char*)job.srcStart + job.dictSize, job.srcSize);
                 if (zcs->frameEnded && (zcs->doneJobID+1 == zcs->nextJobID)) {  /* write checksum at end of last section */
                     U32 const checksum = (U32)XXH64_digest(&zcs->xxhState);
-                    DEBUGLOG(4, "writing checksum : %08X \n", checksum);
+                    DEBUGLOG(5, "writing checksum : %08X \n", checksum);
                     MEM_writeLE32((char*)job.dstBuff.start + job.cSize, checksum);
                     job.cSize += 4;
                     zcs->jobs[wJobID].cSize += 4;
@@ -675,7 +822,7 @@ static size_t ZSTDMT_flushNextJob(ZSTDMT_CCtx* zcs, ZSTD_outBuffer* output, unsi
             zcs->jobs[wJobID].jobScanned = 1;
         }
         {   size_t const toWrite = MIN(job.cSize - job.dstFlushed, output->size - output->pos);
-            DEBUGLOG(4, "Flushing %u bytes from job %u ", (U32)toWrite, zcs->doneJobID);
+            DEBUGLOG(5, "Flushing %u bytes from job %u ", (U32)toWrite, zcs->doneJobID);
             memcpy((char*)output->dst + output->pos, (const char*)job.dstBuff.start + job.dstFlushed, toWrite);
             output->pos += toWrite;
             job.dstFlushed += toWrite;
@@ -696,26 +843,81 @@ static size_t ZSTDMT_flushNextJob(ZSTDMT_CCtx* zcs, ZSTD_outBuffer* output, unsi
 }   }
 
 
-size_t ZSTDMT_compressStream(ZSTDMT_CCtx* zcs, ZSTD_outBuffer* output, ZSTD_inBuffer* input)
+/** ZSTDMT_compressStream_generic() :
+ *  internal use only
+ *  assumption : output and input are valid (pos <= size)
+ * @return : minimum amount of data remaining to flush, 0 if none */
+size_t ZSTDMT_compressStream_generic(ZSTDMT_CCtx* mtctx,
+                                     ZSTD_outBuffer* output,
+                                     ZSTD_inBuffer* input,
+                                     ZSTD_EndDirective endOp)
 {
-    size_t const newJobThreshold = zcs->dictSize + zcs->targetSectionSize + zcs->marginSize;
-    if (zcs->frameEnded) return ERROR(stage_wrong);   /* current frame being ended. Only flush is allowed. Restart with init */
-    if (zcs->nbThreads==1) return ZSTD_compressStream(zcs->cstream, output, input);
+    size_t const newJobThreshold = mtctx->dictSize + mtctx->targetSectionSize + mtctx->marginSize;
+    assert(output->pos <= output->size);
+    assert(input->pos  <= input->size);
+    if ((mtctx->frameEnded) && (endOp==ZSTD_e_continue)) {
+        /* current frame being ended. Only flush/end are allowed. Or start new frame with init */
+        return ERROR(stage_wrong);
+    }
+    if (mtctx->nbThreads==1) {
+        return ZSTD_compressStream_generic(mtctx->cctxPool->cctx[0], output, input, endOp);
+    }
+
+    /* single-pass shortcut (note : this is blocking-mode) */
+    if ( (mtctx->nextJobID==0)      /* just started */
+      && (mtctx->inBuff.filled==0)  /* nothing buffered */
+      && (endOp==ZSTD_e_end)        /* end order */
+      && (output->size - output->pos >= ZSTD_compressBound(input->size - input->pos)) ) { /* enough room */
+        size_t const cSize = ZSTDMT_compress_advanced(mtctx,
+                (char*)output->dst + output->pos, output->size - output->pos,
+                (const char*)input->src + input->pos, input->size - input->pos,
+                mtctx->cdict, mtctx->params, mtctx->overlapRLog);
+        if (ZSTD_isError(cSize)) return cSize;
+        input->pos = input->size;
+        output->pos += cSize;
+        ZSTDMT_releaseBuffer(mtctx->buffPool, mtctx->inBuff.buffer);  /* was allocated in initStream */
+        mtctx->allJobsCompleted = 1;
+        mtctx->frameEnded = 1;
+        return 0;
+    }
 
     /* fill input buffer */
-    {   size_t const toLoad = MIN(input->size - input->pos, zcs->inBuffSize - zcs->inBuff.filled);
-        memcpy((char*)zcs->inBuff.buffer.start + zcs->inBuff.filled, input->src, toLoad);
+    if ((input->src) && (mtctx->inBuff.buffer.start)) {   /* support NULL input */
+        size_t const toLoad = MIN(input->size - input->pos, mtctx->inBuffSize - mtctx->inBuff.filled);
+        DEBUGLOG(2, "inBuff:%08X;  inBuffSize=%u;  ToCopy=%u", (U32)(size_t)mtctx->inBuff.buffer.start, (U32)mtctx->inBuffSize, (U32)toLoad);
+        memcpy((char*)mtctx->inBuff.buffer.start + mtctx->inBuff.filled, (const char*)input->src + input->pos, toLoad);
         input->pos += toLoad;
-        zcs->inBuff.filled += toLoad;
+        mtctx->inBuff.filled += toLoad;
     }
 
-    if ( (zcs->inBuff.filled >= newJobThreshold)  /* filled enough : let's compress */
-        && (zcs->nextJobID <= zcs->doneJobID + zcs->jobIDMask) ) {   /* avoid overwriting job round buffer */
-        CHECK_F( ZSTDMT_createCompressionJob(zcs, zcs->targetSectionSize, 0) );
+    if ( (mtctx->inBuff.filled >= newJobThreshold)  /* filled enough : let's compress */
+      && (mtctx->nextJobID <= mtctx->doneJobID + mtctx->jobIDMask) ) {   /* avoid overwriting job round buffer */
+        CHECK_F( ZSTDMT_createCompressionJob(mtctx, mtctx->targetSectionSize, 0 /* endFrame */) );
     }
 
-    /* check for data to flush */
-    CHECK_F( ZSTDMT_flushNextJob(zcs, output, (zcs->inBuff.filled == zcs->inBuffSize)) ); /* block if it wasn't possible to create new job due to saturation */
+    /* check for potential compressed data ready to be flushed */
+    CHECK_F( ZSTDMT_flushNextJob(mtctx, output, (mtctx->inBuff.filled == mtctx->inBuffSize) /* blockToFlush */) ); /* block if it wasn't possible to create new job due to saturation */
+
+    if (input->pos < input->size)  /* input not consumed : do not flush yet */
+        endOp = ZSTD_e_continue;
+
+    switch(endOp)
+    {
+        case ZSTD_e_flush:
+            return ZSTDMT_flushStream(mtctx, output);
+        case ZSTD_e_end:
+            return ZSTDMT_endStream(mtctx, output);
+        case ZSTD_e_continue:
+            return 1;
+        default:
+            return ERROR(GENERIC);   /* invalid endDirective */
+    }
+}
+
+
+size_t ZSTDMT_compressStream(ZSTDMT_CCtx* zcs, ZSTD_outBuffer* output, ZSTD_inBuffer* input)
+{
+    CHECK_F( ZSTDMT_compressStream_generic(zcs, output, input, ZSTD_e_continue) );
 
     /* recommended next input size : fill current input buffer */
     return zcs->inBuffSize - zcs->inBuff.filled;   /* note : could be zero when input buffer is fully filled and no more availability to create new job */
@@ -726,26 +928,28 @@ static size_t ZSTDMT_flushStream_internal(ZSTDMT_CCtx* zcs, ZSTD_outBuffer* outp
 {
     size_t const srcSize = zcs->inBuff.filled - zcs->dictSize;
 
-    if (srcSize) DEBUGLOG(4, "flushing : %u bytes left to compress", (U32)srcSize);
     if ( ((srcSize > 0) || (endFrame && !zcs->frameEnded))
        && (zcs->nextJobID <= zcs->doneJobID + zcs->jobIDMask) ) {
         CHECK_F( ZSTDMT_createCompressionJob(zcs, srcSize, endFrame) );
     }
 
     /* check if there is any data available to flush */
-    DEBUGLOG(5, "zcs->doneJobID : %u  ; zcs->nextJobID : %u ", zcs->doneJobID, zcs->nextJobID);
-    return ZSTDMT_flushNextJob(zcs, output, 1);
+    return ZSTDMT_flushNextJob(zcs, output, 1 /* blockToFlush */);
 }
 
 
 size_t ZSTDMT_flushStream(ZSTDMT_CCtx* zcs, ZSTD_outBuffer* output)
 {
-    if (zcs->nbThreads==1) return ZSTD_flushStream(zcs->cstream, output);
-    return ZSTDMT_flushStream_internal(zcs, output, 0);
+    DEBUGLOG(5, "ZSTDMT_flushStream");
+    if (zcs->nbThreads==1)
+        return ZSTD_flushStream(zcs->cctxPool->cctx[0], output);
+    return ZSTDMT_flushStream_internal(zcs, output, 0 /* endFrame */);
 }
 
 size_t ZSTDMT_endStream(ZSTDMT_CCtx* zcs, ZSTD_outBuffer* output)
 {
-    if (zcs->nbThreads==1) return ZSTD_endStream(zcs->cstream, output);
-    return ZSTDMT_flushStream_internal(zcs, output, 1);
+    DEBUGLOG(4, "ZSTDMT_endStream");
+    if (zcs->nbThreads==1)
+        return ZSTD_endStream(zcs->cctxPool->cctx[0], output);
+    return ZSTDMT_flushStream_internal(zcs, output, 1 /* endFrame */);
 }
diff --git a/thirdparty/zstd/compress/zstdmt_compress.h b/thirdparty/zstd/compress/zstdmt_compress.h
index 27f78ee031..fad63b6d86 100644
--- a/thirdparty/zstd/compress/zstdmt_compress.h
+++ b/thirdparty/zstd/compress/zstdmt_compress.h
@@ -15,25 +15,34 @@
  #endif
 
 
-/* Note : All prototypes defined in this file shall be considered experimental.
- *        There is no guarantee of API continuity (yet) on any of these prototypes */
+/* Note : All prototypes defined in this file are labelled experimental.
+ *        No guarantee of API continuity is provided on any of them.
+ *        In fact, the expectation is that these prototypes will be replaced
+ *        by ZSTD_compress_generic() API in the near future */
 
 /* ===   Dependencies   === */
-#include <stddef.h>   /* size_t */
+#include <stddef.h>                /* size_t */
 #define ZSTD_STATIC_LINKING_ONLY   /* ZSTD_parameters */
-#include "zstd.h"     /* ZSTD_inBuffer, ZSTD_outBuffer, ZSTDLIB_API */
+#include "zstd.h"            /* ZSTD_inBuffer, ZSTD_outBuffer, ZSTDLIB_API */
 
 
-/* ===   Simple one-pass functions   === */
-
+/* ===   Memory management   === */
 typedef struct ZSTDMT_CCtx_s ZSTDMT_CCtx;
 ZSTDLIB_API ZSTDMT_CCtx* ZSTDMT_createCCtx(unsigned nbThreads);
-ZSTDLIB_API size_t ZSTDMT_freeCCtx(ZSTDMT_CCtx* cctx);
+ZSTDLIB_API ZSTDMT_CCtx* ZSTDMT_createCCtx_advanced(unsigned nbThreads,
+                                                    ZSTD_customMem cMem);
+ZSTDLIB_API size_t ZSTDMT_freeCCtx(ZSTDMT_CCtx* mtctx);
+
+ZSTDLIB_API size_t ZSTDMT_sizeof_CCtx(ZSTDMT_CCtx* mtctx);
+
+
+/* ===   Simple buffer-to-butter one-pass function   === */
+
+ZSTDLIB_API size_t ZSTDMT_compressCCtx(ZSTDMT_CCtx* mtctx,
+                                       void* dst, size_t dstCapacity,
+                                 const void* src, size_t srcSize,
+                                       int compressionLevel);
 
-ZSTDLIB_API size_t ZSTDMT_compressCCtx(ZSTDMT_CCtx* cctx,
-                           void* dst, size_t dstCapacity,
-                     const void* src, size_t srcSize,
-                           int compressionLevel);
 
 
 /* ===   Streaming functions   === */
@@ -53,8 +62,22 @@ ZSTDLIB_API size_t ZSTDMT_endStream(ZSTDMT_CCtx* mtctx, ZSTD_outBuffer* output);
 #  define ZSTDMT_SECTION_SIZE_MIN (1U << 20)   /* 1 MB - Minimum size of each compression job */
 #endif
 
-ZSTDLIB_API size_t ZSTDMT_initCStream_advanced(ZSTDMT_CCtx* mtctx, const void* dict, size_t dictSize,  /**< dict can be released after init, a local copy is preserved within zcs */
-                                          ZSTD_parameters params, unsigned long long pledgedSrcSize);  /**< pledgedSrcSize is optional and can be zero == unknown */
+ZSTDLIB_API size_t ZSTDMT_compress_advanced(ZSTDMT_CCtx* mtctx,
+                                           void* dst, size_t dstCapacity,
+                                     const void* src, size_t srcSize,
+                                     const ZSTD_CDict* cdict,
+                                           ZSTD_parameters const params,
+                                           unsigned overlapRLog);
+
+ZSTDLIB_API size_t ZSTDMT_initCStream_advanced(ZSTDMT_CCtx* mtctx,
+                                        const void* dict, size_t dictSize,   /* dict can be released after init, a local copy is preserved within zcs */
+                                        ZSTD_parameters params,
+                                        unsigned long long pledgedSrcSize);  /* pledgedSrcSize is optional and can be zero == unknown */
+
+ZSTDLIB_API size_t ZSTDMT_initCStream_usingCDict(ZSTDMT_CCtx* mtctx,
+                                        const ZSTD_CDict* cdict,
+                                        ZSTD_frameParameters fparams,
+                                        unsigned long long pledgedSrcSize);  /* note : zero means empty */
 
 /* ZSDTMT_parameter :
  * List of parameters that can be set using ZSTDMT_setMTCtxParameter() */
@@ -71,6 +94,19 @@ typedef enum {
 ZSTDLIB_API size_t ZSTDMT_setMTCtxParameter(ZSTDMT_CCtx* mtctx, ZSDTMT_parameter parameter, unsigned value);
 
 
+/*! ZSTDMT_compressStream_generic() :
+ *  Combines ZSTDMT_compressStream() with ZSTDMT_flushStream() or ZSTDMT_endStream()
+ *  depending on flush directive.
+ * @return : minimum amount of data still to be flushed
+ *           0 if fully flushed
+ *           or an error code */
+ZSTDLIB_API size_t ZSTDMT_compressStream_generic(ZSTDMT_CCtx* mtctx,
+                                                ZSTD_outBuffer* output,
+                                                ZSTD_inBuffer* input,
+                                                ZSTD_EndDirective endOp);
+
+
+
 #if defined (__cplusplus)
 }
 #endif
diff --git a/thirdparty/zstd/decompress/huf_decompress.c b/thirdparty/zstd/decompress/huf_decompress.c
index ea35c36201..2a1b70ea5e 100644
--- a/thirdparty/zstd/decompress/huf_decompress.c
+++ b/thirdparty/zstd/decompress/huf_decompress.c
@@ -67,6 +67,12 @@
 #define HUF_STATIC_ASSERT(c) { enum { HUF_static_assert = 1/(int)(!!(c)) }; }   /* use only *after* variable declarations */
 
 
+/* **************************************************************
+*  Byte alignment for workSpace management
+****************************************************************/
+#define HUF_ALIGN(x, a) HUF_ALIGN_MASK((x), (a) - 1)
+#define HUF_ALIGN_MASK(x, mask) (((x) + (mask)) & ~(mask))
+
 /*-***************************/
 /*  generic DTableDesc       */
 /*-***************************/
@@ -87,16 +93,28 @@ static DTableDesc HUF_getDTableDesc(const HUF_DTable* table)
 
 typedef struct { BYTE byte; BYTE nbBits; } HUF_DEltX2;   /* single-symbol decoding */
 
-size_t HUF_readDTableX2 (HUF_DTable* DTable, const void* src, size_t srcSize)
+size_t HUF_readDTableX2_wksp(HUF_DTable* DTable, const void* src, size_t srcSize, void* workSpace, size_t wkspSize)
 {
-    BYTE huffWeight[HUF_SYMBOLVALUE_MAX + 1];
-    U32 rankVal[HUF_TABLELOG_ABSOLUTEMAX + 1];   /* large enough for values from 0 to 16 */
     U32 tableLog = 0;
     U32 nbSymbols = 0;
     size_t iSize;
     void* const dtPtr = DTable + 1;
     HUF_DEltX2* const dt = (HUF_DEltX2*)dtPtr;
 
+    U32* rankVal;
+    BYTE* huffWeight;
+    size_t spaceUsed32 = 0;
+
+    rankVal = (U32 *)workSpace + spaceUsed32;
+    spaceUsed32 += HUF_TABLELOG_ABSOLUTEMAX + 1;
+    huffWeight = (BYTE *)((U32 *)workSpace + spaceUsed32);
+    spaceUsed32 += HUF_ALIGN(HUF_SYMBOLVALUE_MAX + 1, sizeof(U32)) >> 2;
+
+    if ((spaceUsed32 << 2) > wkspSize)
+        return ERROR(tableLog_tooLarge);
+    workSpace = (U32 *)workSpace + spaceUsed32;
+    wkspSize -= (spaceUsed32 << 2);
+
     HUF_STATIC_ASSERT(sizeof(DTableDesc) == sizeof(HUF_DTable));
     /* memset(huffWeight, 0, sizeof(huffWeight)); */   /* is not necessary, even though some analyzer complain ... */
 
@@ -135,6 +153,13 @@ size_t HUF_readDTableX2 (HUF_DTable* DTable, const void* src, size_t srcSize)
     return iSize;
 }
 
+size_t HUF_readDTableX2(HUF_DTable* DTable, const void* src, size_t srcSize)
+{
+    U32 workSpace[HUF_DECOMPRESS_WORKSPACE_SIZE_U32];
+    return HUF_readDTableX2_wksp(DTable, src, srcSize,
+                                 workSpace, sizeof(workSpace));
+}
+
 
 static BYTE HUF_decodeSymbolX2(BIT_DStream_t* Dstream, const HUF_DEltX2* dt, const U32 dtLog)
 {
@@ -212,11 +237,13 @@ size_t HUF_decompress1X2_usingDTable(
     return HUF_decompress1X2_usingDTable_internal(dst, dstSize, cSrc, cSrcSize, DTable);
 }
 
-size_t HUF_decompress1X2_DCtx (HUF_DTable* DCtx, void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize)
+size_t HUF_decompress1X2_DCtx_wksp(HUF_DTable* DCtx, void* dst, size_t dstSize,
+                                   const void* cSrc, size_t cSrcSize,
+                                   void* workSpace, size_t wkspSize)
 {
     const BYTE* ip = (const BYTE*) cSrc;
 
-    size_t const hSize = HUF_readDTableX2 (DCtx, cSrc, cSrcSize);
+    size_t const hSize = HUF_readDTableX2_wksp(DCtx, cSrc, cSrcSize, workSpace, wkspSize);
     if (HUF_isError(hSize)) return hSize;
     if (hSize >= cSrcSize) return ERROR(srcSize_wrong);
     ip += hSize; cSrcSize -= hSize;
@@ -224,6 +251,15 @@ size_t HUF_decompress1X2_DCtx (HUF_DTable* DCtx, void* dst, size_t dstSize, cons
     return HUF_decompress1X2_usingDTable_internal (dst, dstSize, ip, cSrcSize, DCtx);
 }
 
+
+size_t HUF_decompress1X2_DCtx(HUF_DTable* DCtx, void* dst, size_t dstSize,
+                              const void* cSrc, size_t cSrcSize)
+{
+    U32 workSpace[HUF_DECOMPRESS_WORKSPACE_SIZE_U32];
+    return HUF_decompress1X2_DCtx_wksp(DCtx, dst, dstSize, cSrc, cSrcSize,
+                                       workSpace, sizeof(workSpace));
+}
+
 size_t HUF_decompress1X2 (void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize)
 {
     HUF_CREATE_STATIC_DTABLEX2(DTable, HUF_TABLELOG_MAX);
@@ -335,11 +371,14 @@ size_t HUF_decompress4X2_usingDTable(
 }
 
 
-size_t HUF_decompress4X2_DCtx (HUF_DTable* dctx, void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize)
+size_t HUF_decompress4X2_DCtx_wksp(HUF_DTable* dctx, void* dst, size_t dstSize,
+                                   const void* cSrc, size_t cSrcSize,
+                                   void* workSpace, size_t wkspSize)
 {
     const BYTE* ip = (const BYTE*) cSrc;
 
-    size_t const hSize = HUF_readDTableX2 (dctx, cSrc, cSrcSize);
+    size_t const hSize = HUF_readDTableX2_wksp (dctx, cSrc, cSrcSize,
+                                                workSpace, wkspSize);
     if (HUF_isError(hSize)) return hSize;
     if (hSize >= cSrcSize) return ERROR(srcSize_wrong);
     ip += hSize; cSrcSize -= hSize;
@@ -347,6 +386,13 @@ size_t HUF_decompress4X2_DCtx (HUF_DTable* dctx, void* dst, size_t dstSize, cons
     return HUF_decompress4X2_usingDTable_internal (dst, dstSize, ip, cSrcSize, dctx);
 }
 
+
+size_t HUF_decompress4X2_DCtx (HUF_DTable* dctx, void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize)
+{
+    U32 workSpace[HUF_DECOMPRESS_WORKSPACE_SIZE_U32];
+    return HUF_decompress4X2_DCtx_wksp(dctx, dst, dstSize, cSrc, cSrcSize,
+                                       workSpace, sizeof(workSpace));
+}
 size_t HUF_decompress4X2 (void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize)
 {
     HUF_CREATE_STATIC_DTABLEX2(DTable, HUF_TABLELOG_MAX);
@@ -403,7 +449,8 @@ static void HUF_fillDTableX4Level2(HUF_DEltX4* DTable, U32 sizeLog, const U32 co
     }   }
 }
 
-typedef U32 rankVal_t[HUF_TABLELOG_MAX][HUF_TABLELOG_MAX + 1];
+typedef U32 rankValCol_t[HUF_TABLELOG_MAX + 1];
+typedef rankValCol_t rankVal_t[HUF_TABLELOG_MAX];
 
 static void HUF_fillDTableX4(HUF_DEltX4* DTable, const U32 targetLog,
                            const sortedSymbol_t* sortedList, const U32 sortedListSize,
@@ -447,20 +494,43 @@ static void HUF_fillDTableX4(HUF_DEltX4* DTable, const U32 targetLog,
     }
 }
 
-size_t HUF_readDTableX4 (HUF_DTable* DTable, const void* src, size_t srcSize)
+size_t HUF_readDTableX4_wksp(HUF_DTable* DTable, const void* src,
+                             size_t srcSize, void* workSpace,
+                             size_t wkspSize)
 {
-    BYTE weightList[HUF_SYMBOLVALUE_MAX + 1];
-    sortedSymbol_t sortedSymbol[HUF_SYMBOLVALUE_MAX + 1];
-    U32 rankStats[HUF_TABLELOG_MAX + 1] = { 0 };
-    U32 rankStart0[HUF_TABLELOG_MAX + 2] = { 0 };
-    U32* const rankStart = rankStart0+1;
-    rankVal_t rankVal;
     U32 tableLog, maxW, sizeOfSort, nbSymbols;
     DTableDesc dtd = HUF_getDTableDesc(DTable);
     U32 const maxTableLog = dtd.maxTableLog;
     size_t iSize;
     void* dtPtr = DTable+1;   /* force compiler to avoid strict-aliasing */
     HUF_DEltX4* const dt = (HUF_DEltX4*)dtPtr;
+    U32 *rankStart;
+
+    rankValCol_t* rankVal;
+    U32* rankStats;
+    U32* rankStart0;
+    sortedSymbol_t* sortedSymbol;
+    BYTE* weightList;
+    size_t spaceUsed32 = 0;
+
+    rankVal = (rankValCol_t *)((U32 *)workSpace + spaceUsed32);
+    spaceUsed32 += (sizeof(rankValCol_t) * HUF_TABLELOG_MAX) >> 2;
+    rankStats = (U32 *)workSpace + spaceUsed32;
+    spaceUsed32 += HUF_TABLELOG_MAX + 1;
+    rankStart0 = (U32 *)workSpace + spaceUsed32;
+    spaceUsed32 += HUF_TABLELOG_MAX + 2;
+    sortedSymbol = (sortedSymbol_t *)workSpace + (spaceUsed32 * sizeof(U32)) / sizeof(sortedSymbol_t);
+    spaceUsed32 += HUF_ALIGN(sizeof(sortedSymbol_t) * (HUF_SYMBOLVALUE_MAX + 1), sizeof(U32)) >> 2;
+    weightList = (BYTE *)((U32 *)workSpace + spaceUsed32);
+    spaceUsed32 += HUF_ALIGN(HUF_SYMBOLVALUE_MAX + 1, sizeof(U32)) >> 2;
+
+    if ((spaceUsed32 << 2) > wkspSize)
+        return ERROR(tableLog_tooLarge);
+    workSpace = (U32 *)workSpace + spaceUsed32;
+    wkspSize -= (spaceUsed32 << 2);
+
+    rankStart = rankStart0 + 1;
+    memset(rankStats, 0, sizeof(U32) * (2 * HUF_TABLELOG_MAX + 2 + 1));
 
     HUF_STATIC_ASSERT(sizeof(HUF_DEltX4) == sizeof(HUF_DTable));   /* if compiler fails here, assertion is wrong */
     if (maxTableLog > HUF_TABLELOG_MAX) return ERROR(tableLog_tooLarge);
@@ -527,6 +597,12 @@ size_t HUF_readDTableX4 (HUF_DTable* DTable, const void* src, size_t srcSize)
     return iSize;
 }
 
+size_t HUF_readDTableX4(HUF_DTable* DTable, const void* src, size_t srcSize)
+{
+  U32 workSpace[HUF_DECOMPRESS_WORKSPACE_SIZE_U32];
+  return HUF_readDTableX4_wksp(DTable, src, srcSize,
+                               workSpace, sizeof(workSpace));
+}
 
 static U32 HUF_decodeSymbolX4(void* op, BIT_DStream_t* DStream, const HUF_DEltX4* dt, const U32 dtLog)
 {
@@ -545,7 +621,8 @@ static U32 HUF_decodeLastSymbolX4(void* op, BIT_DStream_t* DStream, const HUF_DE
         if (DStream->bitsConsumed < (sizeof(DStream->bitContainer)*8)) {
             BIT_skipBits(DStream, dt[val].nbBits);
             if (DStream->bitsConsumed > (sizeof(DStream->bitContainer)*8))
-                DStream->bitsConsumed = (sizeof(DStream->bitContainer)*8);   /* ugly hack; works only because it's the last symbol. Note : can't easily extract nbBits from just this symbol */
+                /* ugly hack; works only because it's the last symbol. Note : can't easily extract nbBits from just this symbol */
+                DStream->bitsConsumed = (sizeof(DStream->bitContainer)*8);
     }   }
     return 1;
 }
@@ -626,11 +703,14 @@ size_t HUF_decompress1X4_usingDTable(
     return HUF_decompress1X4_usingDTable_internal(dst, dstSize, cSrc, cSrcSize, DTable);
 }
 
-size_t HUF_decompress1X4_DCtx (HUF_DTable* DCtx, void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize)
+size_t HUF_decompress1X4_DCtx_wksp(HUF_DTable* DCtx, void* dst, size_t dstSize,
+                                   const void* cSrc, size_t cSrcSize,
+                                   void* workSpace, size_t wkspSize)
 {
     const BYTE* ip = (const BYTE*) cSrc;
 
-    size_t const hSize = HUF_readDTableX4 (DCtx, cSrc, cSrcSize);
+    size_t const hSize = HUF_readDTableX4_wksp(DCtx, cSrc, cSrcSize,
+                                               workSpace, wkspSize);
     if (HUF_isError(hSize)) return hSize;
     if (hSize >= cSrcSize) return ERROR(srcSize_wrong);
     ip += hSize; cSrcSize -= hSize;
@@ -638,6 +718,15 @@ size_t HUF_decompress1X4_DCtx (HUF_DTable* DCtx, void* dst, size_t dstSize, cons
     return HUF_decompress1X4_usingDTable_internal (dst, dstSize, ip, cSrcSize, DCtx);
 }
 
+
+size_t HUF_decompress1X4_DCtx(HUF_DTable* DCtx, void* dst, size_t dstSize,
+                              const void* cSrc, size_t cSrcSize)
+{
+    U32 workSpace[HUF_DECOMPRESS_WORKSPACE_SIZE_U32];
+    return HUF_decompress1X4_DCtx_wksp(DCtx, dst, dstSize, cSrc, cSrcSize,
+                                       workSpace, sizeof(workSpace));
+}
+
 size_t HUF_decompress1X4 (void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize)
 {
     HUF_CREATE_STATIC_DTABLEX4(DTable, HUF_TABLELOG_MAX);
@@ -748,11 +837,14 @@ size_t HUF_decompress4X4_usingDTable(
 }
 
 
-size_t HUF_decompress4X4_DCtx (HUF_DTable* dctx, void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize)
+size_t HUF_decompress4X4_DCtx_wksp(HUF_DTable* dctx, void* dst, size_t dstSize,
+                                   const void* cSrc, size_t cSrcSize,
+                                   void* workSpace, size_t wkspSize)
 {
     const BYTE* ip = (const BYTE*) cSrc;
 
-    size_t hSize = HUF_readDTableX4 (dctx, cSrc, cSrcSize);
+    size_t hSize = HUF_readDTableX4_wksp(dctx, cSrc, cSrcSize,
+                                         workSpace, wkspSize);
     if (HUF_isError(hSize)) return hSize;
     if (hSize >= cSrcSize) return ERROR(srcSize_wrong);
     ip += hSize; cSrcSize -= hSize;
@@ -760,6 +852,15 @@ size_t HUF_decompress4X4_DCtx (HUF_DTable* dctx, void* dst, size_t dstSize, cons
     return HUF_decompress4X4_usingDTable_internal(dst, dstSize, ip, cSrcSize, dctx);
 }
 
+
+size_t HUF_decompress4X4_DCtx(HUF_DTable* dctx, void* dst, size_t dstSize,
+                              const void* cSrc, size_t cSrcSize)
+{
+    U32 workSpace[HUF_DECOMPRESS_WORKSPACE_SIZE_U32];
+    return HUF_decompress4X4_DCtx_wksp(dctx, dst, dstSize, cSrc, cSrcSize,
+                                       workSpace, sizeof(workSpace));
+}
+
 size_t HUF_decompress4X4 (void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize)
 {
     HUF_CREATE_STATIC_DTABLEX4(DTable, HUF_TABLELOG_MAX);
@@ -861,19 +962,32 @@ size_t HUF_decompress4X_DCtx (HUF_DTable* dctx, void* dst, size_t dstSize, const
     }
 }
 
-size_t HUF_decompress4X_hufOnly (HUF_DTable* dctx, void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize)
+size_t HUF_decompress4X_hufOnly(HUF_DTable* dctx, void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize)
+{
+    U32 workSpace[HUF_DECOMPRESS_WORKSPACE_SIZE_U32];
+    return HUF_decompress4X_hufOnly_wksp(dctx, dst, dstSize, cSrc, cSrcSize,
+                                         workSpace, sizeof(workSpace));
+}
+
+
+size_t HUF_decompress4X_hufOnly_wksp(HUF_DTable* dctx, void* dst,
+                                     size_t dstSize, const void* cSrc,
+                                     size_t cSrcSize, void* workSpace,
+                                     size_t wkspSize)
 {
     /* validation checks */
     if (dstSize == 0) return ERROR(dstSize_tooSmall);
     if ((cSrcSize >= dstSize) || (cSrcSize <= 1)) return ERROR(corruption_detected);   /* invalid */
 
     {   U32 const algoNb = HUF_selectDecoder(dstSize, cSrcSize);
-        return algoNb ? HUF_decompress4X4_DCtx(dctx, dst, dstSize, cSrc, cSrcSize) :
-                        HUF_decompress4X2_DCtx(dctx, dst, dstSize, cSrc, cSrcSize) ;
+        return algoNb ? HUF_decompress4X4_DCtx_wksp(dctx, dst, dstSize, cSrc, cSrcSize, workSpace, wkspSize):
+                        HUF_decompress4X2_DCtx_wksp(dctx, dst, dstSize, cSrc, cSrcSize, workSpace, wkspSize);
     }
 }
 
-size_t HUF_decompress1X_DCtx (HUF_DTable* dctx, void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize)
+size_t HUF_decompress1X_DCtx_wksp(HUF_DTable* dctx, void* dst, size_t dstSize,
+                                  const void* cSrc, size_t cSrcSize,
+                                  void* workSpace, size_t wkspSize)
 {
     /* validation checks */
     if (dstSize == 0) return ERROR(dstSize_tooSmall);
@@ -882,7 +996,17 @@ size_t HUF_decompress1X_DCtx (HUF_DTable* dctx, void* dst, size_t dstSize, const
     if (cSrcSize == 1) { memset(dst, *(const BYTE*)cSrc, dstSize); return dstSize; }   /* RLE */
 
     {   U32 const algoNb = HUF_selectDecoder(dstSize, cSrcSize);
-        return algoNb ? HUF_decompress1X4_DCtx(dctx, dst, dstSize, cSrc, cSrcSize) :
-                        HUF_decompress1X2_DCtx(dctx, dst, dstSize, cSrc, cSrcSize) ;
+        return algoNb ? HUF_decompress1X4_DCtx_wksp(dctx, dst, dstSize, cSrc,
+                                cSrcSize, workSpace, wkspSize):
+                        HUF_decompress1X2_DCtx_wksp(dctx, dst, dstSize, cSrc,
+                                cSrcSize, workSpace, wkspSize);
     }
 }
+
+size_t HUF_decompress1X_DCtx(HUF_DTable* dctx, void* dst, size_t dstSize,
+                             const void* cSrc, size_t cSrcSize)
+{
+    U32 workSpace[HUF_DECOMPRESS_WORKSPACE_SIZE_U32];
+    return HUF_decompress1X_DCtx_wksp(dctx, dst, dstSize, cSrc, cSrcSize,
+                                      workSpace, sizeof(workSpace));
+}
diff --git a/thirdparty/zstd/decompress/zstd_decompress.c b/thirdparty/zstd/decompress/zstd_decompress.c
index 910f9ab783..003d703a5e 100644
--- a/thirdparty/zstd/decompress/zstd_decompress.c
+++ b/thirdparty/zstd/decompress/zstd_decompress.c
@@ -53,8 +53,7 @@
 #  include "zstd_legacy.h"
 #endif
 
-
-#if defined(_MSC_VER)
+#if defined(_MSC_VER) && !defined(_M_IA64)  /* _mm_prefetch() is not defined for ia64 */
 #  include <mmintrin.h>   /* https://msdn.microsoft.com/fr-fr/library/84szxsww(v=vs.90).aspx */
 #  define ZSTD_PREFETCH(ptr)   _mm_prefetch((const char*)ptr, _MM_HINT_T0)
 #elif defined(__GNUC__)
@@ -63,8 +62,9 @@
 #  define ZSTD_PREFETCH(ptr)   /* disabled */
 #endif
 
+
 /*-*************************************
-*  Macros
+*  Errors
 ***************************************/
 #define ZSTD_isError ERR_isError   /* for inlining */
 #define FSE_isError  ERR_isError
@@ -85,11 +85,15 @@ typedef enum { ZSTDds_getFrameHeaderSize, ZSTDds_decodeFrameHeader,
                ZSTDds_decompressLastBlock, ZSTDds_checkChecksum,
                ZSTDds_decodeSkippableHeader, ZSTDds_skipFrame } ZSTD_dStage;
 
+typedef enum { zdss_init=0, zdss_loadHeader,
+               zdss_read, zdss_load, zdss_flush } ZSTD_dStreamStage;
+
 typedef struct {
     FSE_DTable LLTable[FSE_DTABLE_SIZE_U32(LLFSELog)];
     FSE_DTable OFTable[FSE_DTABLE_SIZE_U32(OffFSELog)];
     FSE_DTable MLTable[FSE_DTABLE_SIZE_U32(MLFSELog)];
     HUF_DTable hufTable[HUF_DTABLE_SIZE(HufLog)];  /* can accommodate HUF_decompress4X */
+    U32 workspace[HUF_DECOMPRESS_WORKSPACE_SIZE_U32];
     U32 rep[ZSTD_REP_NUM];
 } ZSTD_entropyTables_t;
 
@@ -105,7 +109,7 @@ struct ZSTD_DCtx_s
     const void* vBase;            /* virtual start of previous segment if it was just before current one */
     const void* dictEnd;          /* end of previous segment */
     size_t expected;
-    ZSTD_frameParams fParams;
+    ZSTD_frameHeader fParams;
     blockType_e bType;   /* used in ZSTD_decompressContinue(), to transfer blockType between header decoding and block decoding stages */
     ZSTD_dStage stage;
     U32 litEntropy;
@@ -117,11 +121,39 @@ struct ZSTD_DCtx_s
     ZSTD_customMem customMem;
     size_t litSize;
     size_t rleSize;
-    BYTE litBuffer[ZSTD_BLOCKSIZE_ABSOLUTEMAX + WILDCOPY_OVERLENGTH];
+    size_t staticSize;
+
+    /* streaming */
+    ZSTD_DDict* ddictLocal;
+    const ZSTD_DDict* ddict;
+    ZSTD_dStreamStage streamStage;
+    char*  inBuff;
+    size_t inBuffSize;
+    size_t inPos;
+    size_t maxWindowSize;
+    char*  outBuff;
+    size_t outBuffSize;
+    size_t outStart;
+    size_t outEnd;
+    size_t blockSize;
+    size_t lhSize;
+    void* legacyContext;
+    U32 previousLegacyVersion;
+    U32 legacyVersion;
+    U32 hostageByte;
+
+    /* workspace */
+    BYTE litBuffer[ZSTD_BLOCKSIZE_MAX + WILDCOPY_OVERLENGTH];
     BYTE headerBuffer[ZSTD_FRAMEHEADERSIZE_MAX];
 };  /* typedef'd to ZSTD_DCtx within "zstd.h" */
 
-size_t ZSTD_sizeof_DCtx (const ZSTD_DCtx* dctx) { return (dctx==NULL) ? 0 : sizeof(ZSTD_DCtx); }
+size_t ZSTD_sizeof_DCtx (const ZSTD_DCtx* dctx)
+{
+    if (dctx==NULL) return 0;   /* support sizeof NULL */
+    return sizeof(*dctx)
+           + ZSTD_sizeof_DDict(dctx->ddictLocal)
+           + dctx->inBuffSize + dctx->outBuffSize;
+}
 
 size_t ZSTD_estimateDCtxSize(void) { return sizeof(ZSTD_DCtx); }
 
@@ -145,40 +177,76 @@ size_t ZSTD_decompressBegin(ZSTD_DCtx* dctx)
     return 0;
 }
 
+static void ZSTD_initDCtx_internal(ZSTD_DCtx* dctx)
+{
+    ZSTD_decompressBegin(dctx);   /* cannot fail */
+    dctx->staticSize = 0;
+    dctx->maxWindowSize = ZSTD_MAXWINDOWSIZE_DEFAULT;
+    dctx->ddict   = NULL;
+    dctx->ddictLocal = NULL;
+    dctx->inBuff  = NULL;
+    dctx->inBuffSize = 0;
+    dctx->outBuffSize= 0;
+    dctx->streamStage = zdss_init;
+}
+
 ZSTD_DCtx* ZSTD_createDCtx_advanced(ZSTD_customMem customMem)
 {
-    ZSTD_DCtx* dctx;
+    if (!customMem.customAlloc ^ !customMem.customFree) return NULL;
 
-    if (!customMem.customAlloc && !customMem.customFree) customMem = defaultCustomMem;
-    if (!customMem.customAlloc || !customMem.customFree) return NULL;
+    {   ZSTD_DCtx* const dctx = (ZSTD_DCtx*)ZSTD_malloc(sizeof(*dctx), customMem);
+        if (!dctx) return NULL;
+        dctx->customMem = customMem;
+        dctx->legacyContext = NULL;
+        dctx->previousLegacyVersion = 0;
+        ZSTD_initDCtx_internal(dctx);
+        return dctx;
+    }
+}
 
-    dctx = (ZSTD_DCtx*)ZSTD_malloc(sizeof(ZSTD_DCtx), customMem);
-    if (!dctx) return NULL;
-    memcpy(&dctx->customMem, &customMem, sizeof(customMem));
-    ZSTD_decompressBegin(dctx);
+ZSTD_DCtx* ZSTD_initStaticDCtx(void *workspace, size_t workspaceSize)
+{
+    ZSTD_DCtx* dctx = (ZSTD_DCtx*) workspace;
+
+    if ((size_t)workspace & 7) return NULL;  /* 8-aligned */
+    if (workspaceSize < sizeof(ZSTD_DCtx)) return NULL;  /* minimum size */
+
+    ZSTD_initDCtx_internal(dctx);
+    dctx->staticSize = workspaceSize;
+    dctx->inBuff = (char*)(dctx+1);
     return dctx;
 }
 
 ZSTD_DCtx* ZSTD_createDCtx(void)
 {
-    return ZSTD_createDCtx_advanced(defaultCustomMem);
+    return ZSTD_createDCtx_advanced(ZSTD_defaultCMem);
 }
 
 size_t ZSTD_freeDCtx(ZSTD_DCtx* dctx)
 {
     if (dctx==NULL) return 0;   /* support free on NULL */
-    ZSTD_free(dctx, dctx->customMem);
-    return 0;   /* reserved as a potential error code in the future */
+    if (dctx->staticSize) return ERROR(memory_allocation);   /* not compatible with static DCtx */
+    {   ZSTD_customMem const cMem = dctx->customMem;
+        ZSTD_freeDDict(dctx->ddictLocal);
+        dctx->ddictLocal = NULL;
+        ZSTD_free(dctx->inBuff, cMem);
+        dctx->inBuff = NULL;
+#if defined(ZSTD_LEGACY_SUPPORT) && (ZSTD_LEGACY_SUPPORT >= 1)
+        if (dctx->legacyContext)
+            ZSTD_freeLegacyStreamContext(dctx->legacyContext, dctx->previousLegacyVersion);
+#endif
+        ZSTD_free(dctx, cMem);
+        return 0;
+    }
 }
 
+/* no longer useful */
 void ZSTD_copyDCtx(ZSTD_DCtx* dstDCtx, const ZSTD_DCtx* srcDCtx)
 {
-    size_t const workSpaceSize = (ZSTD_BLOCKSIZE_ABSOLUTEMAX+WILDCOPY_OVERLENGTH) + ZSTD_frameHeaderSize_max;
-    memcpy(dstDCtx, srcDCtx, sizeof(ZSTD_DCtx) - workSpaceSize);  /* no need to copy workspace */
+    size_t const toCopy = (size_t)((char*)(&dstDCtx->inBuff) - (char*)dstDCtx);
+    memcpy(dstDCtx, srcDCtx, toCopy);  /* no need to copy workspace */
 }
 
-static void ZSTD_refDDict(ZSTD_DCtx* dstDCtx, const ZSTD_DDict* ddict);
-
 
 /*-*************************************************************
 *   Decompression section
@@ -206,7 +274,7 @@ unsigned ZSTD_isFrame(const void* buffer, size_t size)
 /** ZSTD_frameHeaderSize() :
 *   srcSize must be >= ZSTD_frameHeaderSize_prefix.
 *   @return : size of the Frame Header */
-static size_t ZSTD_frameHeaderSize(const void* src, size_t srcSize)
+size_t ZSTD_frameHeaderSize(const void* src, size_t srcSize)
 {
     if (srcSize < ZSTD_frameHeaderSize_prefix) return ERROR(srcSize_wrong);
     {   BYTE const fhd = ((const BYTE*)src)[4];
@@ -219,22 +287,24 @@ static size_t ZSTD_frameHeaderSize(const void* src, size_t srcSize)
 }
 
 
-/** ZSTD_getFrameParams() :
+/** ZSTD_getFrameHeader() :
 *   decode Frame Header, or require larger `srcSize`.
-*   @return : 0, `fparamsPtr` is correctly filled,
+*   @return : 0, `zfhPtr` is correctly filled,
 *            >0, `srcSize` is too small, result is expected `srcSize`,
 *             or an error code, which can be tested using ZSTD_isError() */
-size_t ZSTD_getFrameParams(ZSTD_frameParams* fparamsPtr, const void* src, size_t srcSize)
+size_t ZSTD_getFrameHeader(ZSTD_frameHeader* zfhPtr, const void* src, size_t srcSize)
 {
     const BYTE* ip = (const BYTE*)src;
-
     if (srcSize < ZSTD_frameHeaderSize_prefix) return ZSTD_frameHeaderSize_prefix;
+
     if (MEM_readLE32(src) != ZSTD_MAGICNUMBER) {
         if ((MEM_readLE32(src) & 0xFFFFFFF0U) == ZSTD_MAGIC_SKIPPABLE_START) {
-            if (srcSize < ZSTD_skippableHeaderSize) return ZSTD_skippableHeaderSize; /* magic number + skippable frame length */
-            memset(fparamsPtr, 0, sizeof(*fparamsPtr));
-            fparamsPtr->frameContentSize = MEM_readLE32((const char *)src + 4);
-            fparamsPtr->windowSize = 0; /* windowSize==0 means a frame is skippable */
+            /* skippable frame */
+            if (srcSize < ZSTD_skippableHeaderSize)
+                return ZSTD_skippableHeaderSize; /* magic number + frame length */
+            memset(zfhPtr, 0, sizeof(*zfhPtr));
+            zfhPtr->frameContentSize = MEM_readLE32((const char *)src + 4);
+            zfhPtr->windowSize = 0; /* windowSize==0 means a frame is skippable */
             return 0;
         }
         return ERROR(prefix_unknown);
@@ -254,11 +324,13 @@ size_t ZSTD_getFrameParams(ZSTD_frameParams* fparamsPtr, const void* src, size_t
         U32 windowSize = 0;
         U32 dictID = 0;
         U64 frameContentSize = 0;
-        if ((fhdByte & 0x08) != 0) return ERROR(frameParameter_unsupported);   /* reserved bits, which must be zero */
+        if ((fhdByte & 0x08) != 0)
+            return ERROR(frameParameter_unsupported);   /* reserved bits, must be zero */
         if (!singleSegment) {
             BYTE const wlByte = ip[pos++];
             U32 const windowLog = (wlByte >> 3) + ZSTD_WINDOWLOG_ABSOLUTEMIN;
-            if (windowLog > ZSTD_WINDOWLOG_MAX) return ERROR(frameParameter_windowTooLarge);  /* avoids issue with 1 << windowLog */
+            if (windowLog > ZSTD_WINDOWLOG_MAX)
+                return ERROR(frameParameter_windowTooLarge);
             windowSize = (1U << windowLog);
             windowSize += (windowSize >> 3) * (wlByte&7);
         }
@@ -281,10 +353,10 @@ size_t ZSTD_getFrameParams(ZSTD_frameParams* fparamsPtr, const void* src, size_t
         }
         if (!windowSize) windowSize = (U32)frameContentSize;
         if (windowSize > windowSizeMax) return ERROR(frameParameter_windowTooLarge);
-        fparamsPtr->frameContentSize = frameContentSize;
-        fparamsPtr->windowSize = windowSize;
-        fparamsPtr->dictID = dictID;
-        fparamsPtr->checksumFlag = checksumFlag;
+        zfhPtr->frameContentSize = frameContentSize;
+        zfhPtr->windowSize = windowSize;
+        zfhPtr->dictID = dictID;
+        zfhPtr->checksumFlag = checksumFlag;
     }
     return 0;
 }
@@ -302,9 +374,8 @@ unsigned long long ZSTD_getFrameContentSize(const void *src, size_t srcSize)
         return ret == 0 ? ZSTD_CONTENTSIZE_UNKNOWN : ret;
     }
 #endif
-    {
-        ZSTD_frameParams fParams;
-        if (ZSTD_getFrameParams(&fParams, src, srcSize) != 0) return ZSTD_CONTENTSIZE_ERROR;
+    {   ZSTD_frameHeader fParams;
+        if (ZSTD_getFrameHeader(&fParams, src, srcSize) != 0) return ZSTD_CONTENTSIZE_ERROR;
         if (fParams.windowSize == 0) {
             /* Either skippable or empty frame, size == 0 either way */
             return 0;
@@ -323,51 +394,48 @@ unsigned long long ZSTD_getFrameContentSize(const void *src, size_t srcSize)
  *  @return : decompressed size of the frames contained */
 unsigned long long ZSTD_findDecompressedSize(const void* src, size_t srcSize)
 {
-    {
-        unsigned long long totalDstSize = 0;
-        while (srcSize >= ZSTD_frameHeaderSize_prefix) {
-            const U32 magicNumber = MEM_readLE32(src);
+    unsigned long long totalDstSize = 0;
 
-            if ((magicNumber & 0xFFFFFFF0U) == ZSTD_MAGIC_SKIPPABLE_START) {
-                size_t skippableSize;
-                if (srcSize < ZSTD_skippableHeaderSize)
-                    return ERROR(srcSize_wrong);
-                skippableSize = MEM_readLE32((const BYTE *)src + 4) +
-                                ZSTD_skippableHeaderSize;
-                if (srcSize < skippableSize) {
-                    return ZSTD_CONTENTSIZE_ERROR;
-                }
-
-                src = (const BYTE *)src + skippableSize;
-                srcSize -= skippableSize;
-                continue;
+    while (srcSize >= ZSTD_frameHeaderSize_prefix) {
+        const U32 magicNumber = MEM_readLE32(src);
+
+        if ((magicNumber & 0xFFFFFFF0U) == ZSTD_MAGIC_SKIPPABLE_START) {
+            size_t skippableSize;
+            if (srcSize < ZSTD_skippableHeaderSize)
+                return ERROR(srcSize_wrong);
+            skippableSize = MEM_readLE32((const BYTE *)src + 4) +
+                            ZSTD_skippableHeaderSize;
+            if (srcSize < skippableSize) {
+                return ZSTD_CONTENTSIZE_ERROR;
             }
 
-            {
-                unsigned long long const ret = ZSTD_getFrameContentSize(src, srcSize);
-                if (ret >= ZSTD_CONTENTSIZE_ERROR) return ret;
+            src = (const BYTE *)src + skippableSize;
+            srcSize -= skippableSize;
+            continue;
+        }
 
-                /* check for overflow */
-                if (totalDstSize + ret < totalDstSize) return ZSTD_CONTENTSIZE_ERROR;
-                totalDstSize += ret;
-            }
-            {
-                size_t const frameSrcSize = ZSTD_findFrameCompressedSize(src, srcSize);
-                if (ZSTD_isError(frameSrcSize)) {
-                    return ZSTD_CONTENTSIZE_ERROR;
-                }
+        {   unsigned long long const ret = ZSTD_getFrameContentSize(src, srcSize);
+            if (ret >= ZSTD_CONTENTSIZE_ERROR) return ret;
 
-                src = (const BYTE *)src + frameSrcSize;
-                srcSize -= frameSrcSize;
-            }
+            /* check for overflow */
+            if (totalDstSize + ret < totalDstSize) return ZSTD_CONTENTSIZE_ERROR;
+            totalDstSize += ret;
         }
+        {   size_t const frameSrcSize = ZSTD_findFrameCompressedSize(src, srcSize);
+            if (ZSTD_isError(frameSrcSize)) {
+                return ZSTD_CONTENTSIZE_ERROR;
+            }
 
-        if (srcSize) {
-            return ZSTD_CONTENTSIZE_ERROR;
+            src = (const BYTE *)src + frameSrcSize;
+            srcSize -= frameSrcSize;
         }
+    }
 
-        return totalDstSize;
+    if (srcSize) {
+        return ZSTD_CONTENTSIZE_ERROR;
     }
+
+    return totalDstSize;
 }
 
 /** ZSTD_getDecompressedSize() :
@@ -389,7 +457,7 @@ unsigned long long ZSTD_getDecompressedSize(const void* src, size_t srcSize)
 *   @return : 0 if success, or an error code, which can be tested using ZSTD_isError() */
 static size_t ZSTD_decodeFrameHeader(ZSTD_DCtx* dctx, const void* src, size_t headerSize)
 {
-    size_t const result = ZSTD_getFrameParams(&(dctx->fParams), src, headerSize);
+    size_t const result = ZSTD_getFrameHeader(&(dctx->fParams), src, headerSize);
     if (ZSTD_isError(result)) return result;  /* invalid header */
     if (result>0) return ERROR(srcSize_wrong);   /* headerSize too small */
     if (dctx->fParams.dictID && (dctx->dictID != dctx->fParams.dictID)) return ERROR(dictionary_wrong);
@@ -485,7 +553,7 @@ size_t ZSTD_decodeLiteralsBlock(ZSTD_DCtx* dctx,
                     litCSize = (lhc >> 22) + (istart[4] << 10);
                     break;
                 }
-                if (litSize > ZSTD_BLOCKSIZE_ABSOLUTEMAX) return ERROR(corruption_detected);
+                if (litSize > ZSTD_BLOCKSIZE_MAX) return ERROR(corruption_detected);
                 if (litCSize + lhSize > srcSize) return ERROR(corruption_detected);
 
                 if (HUF_isError((litEncType==set_repeat) ?
@@ -493,8 +561,10 @@ size_t ZSTD_decodeLiteralsBlock(ZSTD_DCtx* dctx,
                                         HUF_decompress1X_usingDTable(dctx->litBuffer, litSize, istart+lhSize, litCSize, dctx->HUFptr) :
                                         HUF_decompress4X_usingDTable(dctx->litBuffer, litSize, istart+lhSize, litCSize, dctx->HUFptr) ) :
                                     ( singleStream ?
-                                        HUF_decompress1X2_DCtx(dctx->entropy.hufTable, dctx->litBuffer, litSize, istart+lhSize, litCSize) :
-                                        HUF_decompress4X_hufOnly (dctx->entropy.hufTable, dctx->litBuffer, litSize, istart+lhSize, litCSize)) ))
+                                        HUF_decompress1X2_DCtx_wksp(dctx->entropy.hufTable, dctx->litBuffer, litSize, istart+lhSize, litCSize,
+                                                                    dctx->entropy.workspace, sizeof(dctx->entropy.workspace)) :
+                                        HUF_decompress4X_hufOnly_wksp(dctx->entropy.hufTable, dctx->litBuffer, litSize, istart+lhSize, litCSize,
+                                                                      dctx->entropy.workspace, sizeof(dctx->entropy.workspace)))))
                     return ERROR(corruption_detected);
 
                 dctx->litPtr = dctx->litBuffer;
@@ -557,7 +627,7 @@ size_t ZSTD_decodeLiteralsBlock(ZSTD_DCtx* dctx,
                     if (srcSize<4) return ERROR(corruption_detected);   /* srcSize >= MIN_CBLOCK_SIZE == 3; here we need lhSize+1 = 4 */
                     break;
                 }
-                if (litSize > ZSTD_BLOCKSIZE_ABSOLUTEMAX) return ERROR(corruption_detected);
+                if (litSize > ZSTD_BLOCKSIZE_MAX) return ERROR(corruption_detected);
                 memset(dctx->litBuffer, istart[lhSize], litSize + WILDCOPY_OVERLENGTH);
                 dctx->litPtr = dctx->litBuffer;
                 dctx->litSize = litSize;
@@ -684,6 +754,7 @@ size_t ZSTD_decodeSeqHeaders(ZSTD_DCtx* dctx, int* nbSeqPtr,
     const BYTE* const istart = (const BYTE* const)src;
     const BYTE* const iend = istart + srcSize;
     const BYTE* ip = istart;
+    DEBUGLOG(5, "ZSTD_decodeSeqHeaders");
 
     /* check */
     if (srcSize < MIN_SEQUENCES_SIZE) return ERROR(srcSize_wrong);
@@ -864,12 +935,18 @@ static seq_t ZSTD_decodeSequence(seqState_t* seqState)
         seq.offset = offset;
     }
 
-    seq.matchLength = ML_base[mlCode] + ((mlCode>31) ? BIT_readBitsFast(&seqState->DStream, mlBits) : 0);  /* <=  16 bits */
+    seq.matchLength = ML_base[mlCode]
+                    + ((mlCode>31) ? BIT_readBitsFast(&seqState->DStream, mlBits) : 0);  /* <=  16 bits */
     if (MEM_32bits() && (mlBits+llBits>24)) BIT_reloadDStream(&seqState->DStream);
 
-    seq.litLength = LL_base[llCode] + ((llCode>15) ? BIT_readBitsFast(&seqState->DStream, llBits) : 0);    /* <=  16 bits */
-    if (MEM_32bits() ||
-       (totalBits > 64 - 7 - (LLFSELog+MLFSELog+OffFSELog)) ) BIT_reloadDStream(&seqState->DStream);
+    seq.litLength = LL_base[llCode]
+                  + ((llCode>15) ? BIT_readBitsFast(&seqState->DStream, llBits) : 0);    /* <=  16 bits */
+    if (  MEM_32bits()
+      || (totalBits > 64 - 7 - (LLFSELog+MLFSELog+OffFSELog)) )
+       BIT_reloadDStream(&seqState->DStream);
+
+    DEBUGLOG(6, "seq: litL=%u, matchL=%u, offset=%u",
+                (U32)seq.litLength, (U32)seq.matchLength, (U32)seq.offset);
 
     /* ANS state update */
     FSE_updateState(&seqState->stateLL, &seqState->DStream);    /* <=  9 bits */
@@ -909,7 +986,8 @@ size_t ZSTD_execSequence(BYTE* op,
     /* copy Match */
     if (sequence.offset > (size_t)(oLitEnd - base)) {
         /* offset beyond prefix -> go into extDict */
-        if (sequence.offset > (size_t)(oLitEnd - vBase)) return ERROR(corruption_detected);
+        if (sequence.offset > (size_t)(oLitEnd - vBase))
+            return ERROR(corruption_detected);
         match = dictEnd + (match - base);
         if (match + sequence.matchLength <= dictEnd) {
             memmove(oLitEnd, match, sequence.matchLength);
@@ -977,9 +1055,12 @@ static size_t ZSTD_decompressSequences(
     const BYTE* const vBase = (const BYTE*) (dctx->vBase);
     const BYTE* const dictEnd = (const BYTE*) (dctx->dictEnd);
     int nbSeq;
+    DEBUGLOG(5, "ZSTD_decompressSequences");
 
     /* Build Decoding Tables */
     {   size_t const seqHSize = ZSTD_decodeSeqHeaders(dctx, &nbSeq, ip, seqSize);
+        DEBUGLOG(5, "ZSTD_decodeSeqHeaders: size=%u, nbSeq=%i",
+                    (U32)seqHSize, nbSeq);
         if (ZSTD_isError(seqHSize)) return seqHSize;
         ip += seqHSize;
     }
@@ -998,11 +1079,13 @@ static size_t ZSTD_decompressSequences(
             nbSeq--;
             {   seq_t const sequence = ZSTD_decodeSequence(&seqState);
                 size_t const oneSeqSize = ZSTD_execSequence(op, oend, sequence, &litPtr, litEnd, base, vBase, dictEnd);
+                DEBUGLOG(6, "regenerated sequence size : %u", (U32)oneSeqSize);
                 if (ZSTD_isError(oneSeqSize)) return oneSeqSize;
                 op += oneSeqSize;
         }   }
 
         /* check if reached exact end */
+        DEBUGLOG(5, "after decode loop, remaining nbSeq : %i", nbSeq);
         if (nbSeq) return ERROR(corruption_detected);
         /* save reps for next block */
         { U32 i; for (i=0; i<ZSTD_REP_NUM; i++) dctx->entropy.rep[i] = (U32)(seqState.prevOffset[i]); }
@@ -1216,7 +1299,7 @@ static size_t ZSTD_decompressSequencesLong(
     const BYTE* const base = (const BYTE*) (dctx->base);
     const BYTE* const vBase = (const BYTE*) (dctx->vBase);
     const BYTE* const dictEnd = (const BYTE*) (dctx->dictEnd);
-    unsigned const windowSize = dctx->fParams.windowSize;
+    unsigned const windowSize32 = (unsigned)dctx->fParams.windowSize;
     int nbSeq;
 
     /* Build Decoding Tables */
@@ -1246,13 +1329,13 @@ static size_t ZSTD_decompressSequencesLong(
 
         /* prepare in advance */
         for (seqNb=0; (BIT_reloadDStream(&seqState.DStream) <= BIT_DStream_completed) && seqNb<seqAdvance; seqNb++) {
-            sequences[seqNb] = ZSTD_decodeSequenceLong(&seqState, windowSize);
+            sequences[seqNb] = ZSTD_decodeSequenceLong(&seqState, windowSize32);
         }
         if (seqNb<seqAdvance) return ERROR(corruption_detected);
 
         /* decode and decompress */
         for ( ; (BIT_reloadDStream(&(seqState.DStream)) <= BIT_DStream_completed) && seqNb<nbSeq ; seqNb++) {
-            seq_t const sequence = ZSTD_decodeSequenceLong(&seqState, windowSize);
+            seq_t const sequence = ZSTD_decodeSequenceLong(&seqState, windowSize32);
             size_t const oneSeqSize = ZSTD_execSequenceLong(op, oend, sequences[(seqNb-ADVANCED_SEQS) & STOSEQ_MASK], &litPtr, litEnd, base, vBase, dictEnd);
             if (ZSTD_isError(oneSeqSize)) return oneSeqSize;
             ZSTD_PREFETCH(sequence.match);
@@ -1289,11 +1372,13 @@ static size_t ZSTD_decompressBlock_internal(ZSTD_DCtx* dctx,
                       const void* src, size_t srcSize)
 {   /* blockType == blockCompressed */
     const BYTE* ip = (const BYTE*)src;
+    DEBUGLOG(5, "ZSTD_decompressBlock_internal");
 
-    if (srcSize >= ZSTD_BLOCKSIZE_ABSOLUTEMAX) return ERROR(srcSize_wrong);
+    if (srcSize >= ZSTD_BLOCKSIZE_MAX) return ERROR(srcSize_wrong);
 
     /* Decode literals section */
     {   size_t const litCSize = ZSTD_decodeLiteralsBlock(dctx, src, srcSize);
+        DEBUGLOG(5, "ZSTD_decodeLiteralsBlock : %u", (U32)litCSize);
         if (ZSTD_isError(litCSize)) return litCSize;
         ip += litCSize;
         srcSize -= litCSize;
@@ -1364,13 +1449,13 @@ size_t ZSTD_findFrameCompressedSize(const void *src, size_t srcSize)
         const BYTE* ip = (const BYTE*)src;
         const BYTE* const ipstart = ip;
         size_t remainingSize = srcSize;
-        ZSTD_frameParams fParams;
+        ZSTD_frameHeader fParams;
 
         size_t const headerSize = ZSTD_frameHeaderSize(ip, remainingSize);
         if (ZSTD_isError(headerSize)) return headerSize;
 
         /* Frame Header */
-        {   size_t const ret = ZSTD_getFrameParams(&fParams, ip, remainingSize);
+        {   size_t const ret = ZSTD_getFrameHeader(&fParams, ip, remainingSize);
             if (ZSTD_isError(ret)) return ret;
             if (ret > 0) return ERROR(srcSize_wrong);
         }
@@ -1505,6 +1590,8 @@ static size_t ZSTD_decompressMultiFrame(ZSTD_DCtx* dctx,
             size_t decodedSize;
             size_t const frameSize = ZSTD_findFrameCompressedSizeLegacy(src, srcSize);
             if (ZSTD_isError(frameSize)) return frameSize;
+            /* legacy support is incompatible with static dctx */
+            if (dctx->staticSize) return ERROR(memory_allocation);
 
             decodedSize = ZSTD_decompressLegacy(dst, dstCapacity, src, frameSize, dict, dictSize);
 
@@ -1540,7 +1627,7 @@ static size_t ZSTD_decompressMultiFrame(ZSTD_DCtx* dctx,
 
         if (ddict) {
             /* we were called from ZSTD_decompress_usingDDict */
-            ZSTD_refDDict(dctx, ddict);
+            CHECK_F(ZSTD_decompressBegin_usingDDict(dctx, ddict));
         } else {
             /* this will initialize correctly with no dict if dict == NULL, so
              * use this in all cases but ddict */
@@ -1580,7 +1667,7 @@ size_t ZSTD_decompressDCtx(ZSTD_DCtx* dctx, void* dst, size_t dstCapacity, const
 
 size_t ZSTD_decompress(void* dst, size_t dstCapacity, const void* src, size_t srcSize)
 {
-#if defined(ZSTD_HEAPMODE) && (ZSTD_HEAPMODE==1)
+#if defined(ZSTD_HEAPMODE) && (ZSTD_HEAPMODE>=1)
     size_t regenSize;
     ZSTD_DCtx* const dctx = ZSTD_createDCtx();
     if (dctx==NULL) return ERROR(memory_allocation);
@@ -1604,6 +1691,7 @@ ZSTD_nextInputType_e ZSTD_nextInputType(ZSTD_DCtx* dctx) {
     switch(dctx->stage)
     {
     default:   /* should not happen */
+        assert(0);
     case ZSTDds_getFrameHeaderSize:
     case ZSTDds_decodeFrameHeader:
         return ZSTDnit_frameHeader;
@@ -1621,21 +1709,24 @@ ZSTD_nextInputType_e ZSTD_nextInputType(ZSTD_DCtx* dctx) {
     }
 }
 
-int ZSTD_isSkipFrame(ZSTD_DCtx* dctx) { return dctx->stage == ZSTDds_skipFrame; }   /* for zbuff */
+static int ZSTD_isSkipFrame(ZSTD_DCtx* dctx) { return dctx->stage == ZSTDds_skipFrame; }
 
 /** ZSTD_decompressContinue() :
-*   @return : nb of bytes generated into `dst` (necessarily <= `dstCapacity)
-*             or an error code, which can be tested using ZSTD_isError() */
+ *  srcSize : must be the exact nb of bytes expected (see ZSTD_nextSrcSizeToDecompress())
+ *  @return : nb of bytes generated into `dst` (necessarily <= `dstCapacity)
+ *            or an error code, which can be tested using ZSTD_isError() */
 size_t ZSTD_decompressContinue(ZSTD_DCtx* dctx, void* dst, size_t dstCapacity, const void* src, size_t srcSize)
 {
+    DEBUGLOG(5, "ZSTD_decompressContinue");
     /* Sanity check */
-    if (srcSize != dctx->expected) return ERROR(srcSize_wrong);
+    if (srcSize != dctx->expected) return ERROR(srcSize_wrong);   /* unauthorized */
     if (dstCapacity) ZSTD_checkContinuity(dctx, dst);
 
     switch (dctx->stage)
     {
     case ZSTDds_getFrameHeaderSize :
-        if (srcSize != ZSTD_frameHeaderSize_prefix) return ERROR(srcSize_wrong);      /* impossible */
+        if (srcSize != ZSTD_frameHeaderSize_prefix) return ERROR(srcSize_wrong);      /* unauthorized */
+        assert(src != NULL);
         if ((MEM_readLE32(src) & 0xFFFFFFF0U) == ZSTD_MAGIC_SKIPPABLE_START) {        /* skippable frame */
             memcpy(dctx->headerBuffer, src, ZSTD_frameHeaderSize_prefix);
             dctx->expected = ZSTD_skippableHeaderSize - ZSTD_frameHeaderSize_prefix;  /* magic number + skippable frame length */
@@ -1653,6 +1744,7 @@ size_t ZSTD_decompressContinue(ZSTD_DCtx* dctx, void* dst, size_t dstCapacity, c
         dctx->expected = 0;   /* not necessary to copy more */
 
     case ZSTDds_decodeFrameHeader:
+        assert(src != NULL);
         memcpy(dctx->headerBuffer + ZSTD_frameHeaderSize_prefix, src, dctx->expected);
         CHECK_F(ZSTD_decodeFrameHeader(dctx, dctx->headerBuffer, dctx->headerSize));
         dctx->expected = ZSTD_blockHeaderSize;
@@ -1680,17 +1772,19 @@ size_t ZSTD_decompressContinue(ZSTD_DCtx* dctx, void* dst, size_t dstCapacity, c
                     dctx->stage = ZSTDds_getFrameHeaderSize;
                 }
             } else {
-                dctx->expected = 3;  /* go directly to next header */
+                dctx->expected = ZSTD_blockHeaderSize;  /* jump to next header */
                 dctx->stage = ZSTDds_decodeBlockHeader;
             }
             return 0;
         }
     case ZSTDds_decompressLastBlock:
     case ZSTDds_decompressBlock:
+        DEBUGLOG(5, "case ZSTDds_decompressBlock");
         {   size_t rSize;
             switch(dctx->bType)
             {
             case bt_compressed:
+                DEBUGLOG(5, "case bt_compressed");
                 rSize = ZSTD_decompressBlock_internal(dctx, dst, dstCapacity, src, srcSize);
                 break;
             case bt_raw :
@@ -1730,7 +1824,8 @@ size_t ZSTD_decompressContinue(ZSTD_DCtx* dctx, void* dst, size_t dstCapacity, c
             return 0;
         }
     case ZSTDds_decodeSkippableHeader:
-        {   memcpy(dctx->headerBuffer + ZSTD_frameHeaderSize_prefix, src, dctx->expected);
+        {   assert(src != NULL);
+            memcpy(dctx->headerBuffer + ZSTD_frameHeaderSize_prefix, src, dctx->expected);
             dctx->expected = MEM_readLE32(dctx->headerBuffer + 4);
             dctx->stage = ZSTDds_skipFrame;
             return 0;
@@ -1767,7 +1862,9 @@ static size_t ZSTD_loadEntropy(ZSTD_entropyTables_t* entropy, const void* const
     dictPtr += 8;   /* skip header = magic + dictID */
 
 
-    {   size_t const hSize = HUF_readDTableX4(entropy->hufTable, dictPtr, dictEnd-dictPtr);
+    {   size_t const hSize = HUF_readDTableX4_wksp(
+            entropy->hufTable, dictPtr, dictEnd - dictPtr,
+            entropy->workspace, sizeof(entropy->workspace));
         if (HUF_isError(hSize)) return ERROR(dictionary_corrupted);
         dictPtr += hSize;
     }
@@ -1815,7 +1912,7 @@ static size_t ZSTD_decompress_insertDictionary(ZSTD_DCtx* dctx, const void* dict
 {
     if (dictSize < 8) return ZSTD_refDictContent(dctx, dict, dictSize);
     {   U32 const magic = MEM_readLE32(dict);
-        if (magic != ZSTD_DICT_MAGIC) {
+        if (magic != ZSTD_MAGIC_DICTIONARY) {
             return ZSTD_refDictContent(dctx, dict, dictSize);   /* pure content mode */
     }   }
     dctx->dictID = MEM_readLE32((const char*)dict + 4);
@@ -1862,10 +1959,10 @@ static size_t ZSTD_DDictDictSize(const ZSTD_DDict* ddict)
     return ddict->dictSize;
 }
 
-static void ZSTD_refDDict(ZSTD_DCtx* dstDCtx, const ZSTD_DDict* ddict)
+size_t ZSTD_decompressBegin_usingDDict(ZSTD_DCtx* dstDCtx, const ZSTD_DDict* ddict)
 {
-    ZSTD_decompressBegin(dstDCtx);  /* init */
-    if (ddict) {   /* support refDDict on NULL */
+    CHECK_F(ZSTD_decompressBegin(dstDCtx));
+    if (ddict) {   /* support begin on NULL */
         dstDCtx->dictID = ddict->dictID;
         dstDCtx->base = ddict->dictContent;
         dstDCtx->vBase = ddict->dictContent;
@@ -1886,6 +1983,7 @@ static void ZSTD_refDDict(ZSTD_DCtx* dstDCtx, const ZSTD_DDict* ddict)
             dstDCtx->fseEntropy = 0;
         }
     }
+    return 0;
 }
 
 static size_t ZSTD_loadEntropy_inDDict(ZSTD_DDict* ddict)
@@ -1894,7 +1992,7 @@ static size_t ZSTD_loadEntropy_inDDict(ZSTD_DDict* ddict)
     ddict->entropyPresent = 0;
     if (ddict->dictSize < 8) return 0;
     {   U32 const magic = MEM_readLE32(ddict->dictContent);
-        if (magic != ZSTD_DICT_MAGIC) return 0;   /* pure content mode */
+        if (magic != ZSTD_MAGIC_DICTIONARY) return 0;   /* pure content mode */
     }
     ddict->dictID = MEM_readLE32((const char*)ddict->dictContent + 4);
 
@@ -1905,33 +2003,39 @@ static size_t ZSTD_loadEntropy_inDDict(ZSTD_DDict* ddict)
 }
 
 
+static size_t ZSTD_initDDict_internal(ZSTD_DDict* ddict, const void* dict, size_t dictSize, unsigned byReference)
+{
+    if ((byReference) || (!dict) || (!dictSize)) {
+        ddict->dictBuffer = NULL;
+        ddict->dictContent = dict;
+    } else {
+        void* const internalBuffer = ZSTD_malloc(dictSize, ddict->cMem);
+        ddict->dictBuffer = internalBuffer;
+        ddict->dictContent = internalBuffer;
+        if (!internalBuffer) return ERROR(memory_allocation);
+        memcpy(internalBuffer, dict, dictSize);
+    }
+    ddict->dictSize = dictSize;
+    ddict->entropy.hufTable[0] = (HUF_DTable)((HufLog)*0x1000001);  /* cover both little and big endian */
+
+    /* parse dictionary content */
+    CHECK_F( ZSTD_loadEntropy_inDDict(ddict) );
+
+    return 0;
+}
+
 ZSTD_DDict* ZSTD_createDDict_advanced(const void* dict, size_t dictSize, unsigned byReference, ZSTD_customMem customMem)
 {
-    if (!customMem.customAlloc && !customMem.customFree) customMem = defaultCustomMem;
-    if (!customMem.customAlloc || !customMem.customFree) return NULL;
+    if (!customMem.customAlloc ^ !customMem.customFree) return NULL;
 
     {   ZSTD_DDict* const ddict = (ZSTD_DDict*) ZSTD_malloc(sizeof(ZSTD_DDict), customMem);
         if (!ddict) return NULL;
         ddict->cMem = customMem;
 
-        if ((byReference) || (!dict) || (!dictSize)) {
-            ddict->dictBuffer = NULL;
-            ddict->dictContent = dict;
-        } else {
-            void* const internalBuffer = ZSTD_malloc(dictSize, customMem);
-            if (!internalBuffer) { ZSTD_freeDDict(ddict); return NULL; }
-            memcpy(internalBuffer, dict, dictSize);
-            ddict->dictBuffer = internalBuffer;
-            ddict->dictContent = internalBuffer;
+        if (ZSTD_isError( ZSTD_initDDict_internal(ddict, dict, dictSize, byReference) )) {
+            ZSTD_freeDDict(ddict);
+            return NULL;
         }
-        ddict->dictSize = dictSize;
-        ddict->entropy.hufTable[0] = (HUF_DTable)((HufLog)*0x1000001);  /* cover both little and big endian */
-        /* parse dictionary content */
-        {   size_t const errorCode = ZSTD_loadEntropy_inDDict(ddict);
-            if (ZSTD_isError(errorCode)) {
-                ZSTD_freeDDict(ddict);
-                return NULL;
-        }   }
 
         return ddict;
     }
@@ -1947,7 +2051,6 @@ ZSTD_DDict* ZSTD_createDDict(const void* dict, size_t dictSize)
     return ZSTD_createDDict_advanced(dict, dictSize, 0, allocator);
 }
 
-
 /*! ZSTD_createDDict_byReference() :
  *  Create a digested dictionary, to start decompression without startup delay.
  *  Dictionary content is simply referenced, it will be accessed during decompression.
@@ -1959,6 +2062,26 @@ ZSTD_DDict* ZSTD_createDDict_byReference(const void* dictBuffer, size_t dictSize
 }
 
 
+ZSTD_DDict* ZSTD_initStaticDDict(void* workspace, size_t workspaceSize,
+                                 const void* dict, size_t dictSize,
+                                 unsigned byReference)
+{
+    size_t const neededSpace = sizeof(ZSTD_DDict) + (byReference ? 0 : dictSize);
+    ZSTD_DDict* const ddict = (ZSTD_DDict*)workspace;
+    assert(workspace != NULL);
+    assert(dict != NULL);
+    if ((size_t)workspace & 7) return NULL;  /* 8-aligned */
+    if (workspaceSize < neededSpace) return NULL;
+    if (!byReference) {
+        memcpy(ddict+1, dict, dictSize);  /* local copy */
+        dict = ddict+1;
+    }
+    if (ZSTD_isError( ZSTD_initDDict_internal(ddict, dict, dictSize, 1 /* byRef */) ))
+        return NULL;
+    return ddict;
+}
+
+
 size_t ZSTD_freeDDict(ZSTD_DDict* ddict)
 {
     if (ddict==NULL) return 0;   /* support free on NULL */
@@ -1969,6 +2092,14 @@ size_t ZSTD_freeDDict(ZSTD_DDict* ddict)
     }
 }
 
+/*! ZSTD_estimateDDictSize() :
+ *  Estimate amount of memory that will be needed to create a dictionary for decompression.
+ *  Note : dictionary created "byReference" are smaller */
+size_t ZSTD_estimateDDictSize(size_t dictSize, unsigned byReference)
+{
+    return sizeof(ZSTD_DDict) + (byReference ? 0 : dictSize);
+}
+
 size_t ZSTD_sizeof_DDict(const ZSTD_DDict* ddict)
 {
     if (ddict==NULL) return 0;   /* support sizeof on NULL */
@@ -1982,7 +2113,7 @@ size_t ZSTD_sizeof_DDict(const ZSTD_DDict* ddict)
 unsigned ZSTD_getDictID_fromDict(const void* dict, size_t dictSize)
 {
     if (dictSize < 8) return 0;
-    if (MEM_readLE32(dict) != ZSTD_DICT_MAGIC) return 0;
+    if (MEM_readLE32(dict) != ZSTD_MAGIC_DICTIONARY) return 0;
     return MEM_readLE32((const char*)dict + 4);
 }
 
@@ -2008,11 +2139,11 @@ unsigned ZSTD_getDictID_fromDDict(const ZSTD_DDict* ddict)
  *    Note : possible if `srcSize < ZSTD_FRAMEHEADERSIZE_MAX`.
  *  - This is not a Zstandard frame.
  *  When identifying the exact failure cause, it's possible to use
- *  ZSTD_getFrameParams(), which will provide a more precise error code. */
+ *  ZSTD_getFrameHeader(), which will provide a more precise error code. */
 unsigned ZSTD_getDictID_fromFrame(const void* src, size_t srcSize)
 {
-    ZSTD_frameParams zfp = { 0 , 0 , 0 , 0 };
-    size_t const hError = ZSTD_getFrameParams(&zfp, src, srcSize);
+    ZSTD_frameHeader zfp = { 0 , 0 , 0 , 0 };
+    size_t const hError = ZSTD_getFrameHeader(&zfp, src, srcSize);
     if (ZSTD_isError(hError)) return 0;
     return zfp.dictID;
 }
@@ -2037,88 +2168,35 @@ size_t ZSTD_decompress_usingDDict(ZSTD_DCtx* dctx,
 *   Streaming decompression
 *====================================*/
 
-typedef enum { zdss_init, zdss_loadHeader,
-               zdss_read, zdss_load, zdss_flush } ZSTD_dStreamStage;
-
-/* *** Resource management *** */
-struct ZSTD_DStream_s {
-    ZSTD_DCtx* dctx;
-    ZSTD_DDict* ddictLocal;
-    const ZSTD_DDict* ddict;
-    ZSTD_frameParams fParams;
-    ZSTD_dStreamStage stage;
-    char*  inBuff;
-    size_t inBuffSize;
-    size_t inPos;
-    size_t maxWindowSize;
-    char*  outBuff;
-    size_t outBuffSize;
-    size_t outStart;
-    size_t outEnd;
-    size_t blockSize;
-    BYTE headerBuffer[ZSTD_FRAMEHEADERSIZE_MAX];   /* tmp buffer to store frame header */
-    size_t lhSize;
-    ZSTD_customMem customMem;
-    void* legacyContext;
-    U32 previousLegacyVersion;
-    U32 legacyVersion;
-    U32 hostageByte;
-};   /* typedef'd to ZSTD_DStream within "zstd.h" */
-
-
 ZSTD_DStream* ZSTD_createDStream(void)
 {
-    return ZSTD_createDStream_advanced(defaultCustomMem);
+    return ZSTD_createDStream_advanced(ZSTD_defaultCMem);
 }
 
-ZSTD_DStream* ZSTD_createDStream_advanced(ZSTD_customMem customMem)
+ZSTD_DStream* ZSTD_initStaticDStream(void *workspace, size_t workspaceSize)
 {
-    ZSTD_DStream* zds;
-
-    if (!customMem.customAlloc && !customMem.customFree) customMem = defaultCustomMem;
-    if (!customMem.customAlloc || !customMem.customFree) return NULL;
+    return ZSTD_initStaticDCtx(workspace, workspaceSize);
+}
 
-    zds = (ZSTD_DStream*) ZSTD_malloc(sizeof(ZSTD_DStream), customMem);
-    if (zds==NULL) return NULL;
-    memset(zds, 0, sizeof(ZSTD_DStream));
-    memcpy(&zds->customMem, &customMem, sizeof(ZSTD_customMem));
-    zds->dctx = ZSTD_createDCtx_advanced(customMem);
-    if (zds->dctx == NULL) { ZSTD_freeDStream(zds); return NULL; }
-    zds->stage = zdss_init;
-    zds->maxWindowSize = ZSTD_MAXWINDOWSIZE_DEFAULT;
-    return zds;
+ZSTD_DStream* ZSTD_createDStream_advanced(ZSTD_customMem customMem)
+{
+    return ZSTD_createDCtx_advanced(customMem);
 }
 
 size_t ZSTD_freeDStream(ZSTD_DStream* zds)
 {
-    if (zds==NULL) return 0;   /* support free on null */
-    {   ZSTD_customMem const cMem = zds->customMem;
-        ZSTD_freeDCtx(zds->dctx);
-        zds->dctx = NULL;
-        ZSTD_freeDDict(zds->ddictLocal);
-        zds->ddictLocal = NULL;
-        ZSTD_free(zds->inBuff, cMem);
-        zds->inBuff = NULL;
-        ZSTD_free(zds->outBuff, cMem);
-        zds->outBuff = NULL;
-#if defined(ZSTD_LEGACY_SUPPORT) && (ZSTD_LEGACY_SUPPORT >= 1)
-        if (zds->legacyContext)
-            ZSTD_freeLegacyStreamContext(zds->legacyContext, zds->previousLegacyVersion);
-#endif
-        ZSTD_free(zds, cMem);
-        return 0;
-    }
+    return ZSTD_freeDCtx(zds);
 }
 
 
 /* *** Initialization *** */
 
-size_t ZSTD_DStreamInSize(void)  { return ZSTD_BLOCKSIZE_ABSOLUTEMAX + ZSTD_blockHeaderSize; }
-size_t ZSTD_DStreamOutSize(void) { return ZSTD_BLOCKSIZE_ABSOLUTEMAX; }
+size_t ZSTD_DStreamInSize(void)  { return ZSTD_BLOCKSIZE_MAX + ZSTD_blockHeaderSize; }
+size_t ZSTD_DStreamOutSize(void) { return ZSTD_BLOCKSIZE_MAX; }
 
 size_t ZSTD_initDStream_usingDict(ZSTD_DStream* zds, const void* dict, size_t dictSize)
 {
-    zds->stage = zdss_loadHeader;
+    zds->streamStage = zdss_loadHeader;
     zds->lhSize = zds->inPos = zds->outStart = zds->outEnd = 0;
     ZSTD_freeDDict(zds->ddictLocal);
     if (dict && dictSize >= 8) {
@@ -2147,7 +2225,7 @@ size_t ZSTD_initDStream_usingDDict(ZSTD_DStream* zds, const ZSTD_DDict* ddict)
 
 size_t ZSTD_resetDStream(ZSTD_DStream* zds)
 {
-    zds->stage = zdss_loadHeader;
+    zds->streamStage = zdss_loadHeader;
     zds->lhSize = zds->inPos = zds->outStart = zds->outEnd = 0;
     zds->legacyVersion = 0;
     zds->hostageByte = 0;
@@ -2168,11 +2246,24 @@ size_t ZSTD_setDStreamParameter(ZSTD_DStream* zds,
 
 size_t ZSTD_sizeof_DStream(const ZSTD_DStream* zds)
 {
-    if (zds==NULL) return 0;   /* support sizeof NULL */
-    return sizeof(*zds)
-           + ZSTD_sizeof_DCtx(zds->dctx)
-           + ZSTD_sizeof_DDict(zds->ddictLocal)
-           + zds->inBuffSize + zds->outBuffSize;
+    return ZSTD_sizeof_DCtx(zds);
+}
+
+size_t ZSTD_estimateDStreamSize(size_t windowSize)
+{
+    size_t const blockSize = MIN(windowSize, ZSTD_BLOCKSIZE_MAX);
+    size_t const inBuffSize = blockSize;  /* no block can be larger */
+    size_t const outBuffSize = windowSize + blockSize + (WILDCOPY_OVERLENGTH * 2);
+    return sizeof(ZSTD_DStream) + ZSTD_estimateDCtxSize() + inBuffSize + outBuffSize;
+}
+
+ZSTDLIB_API size_t ZSTD_estimateDStreamSize_fromFrame(const void* src, size_t srcSize)
+{
+    ZSTD_frameHeader fh;
+    size_t const err = ZSTD_getFrameHeader(&fh, src, srcSize);
+    if (ZSTD_isError(err)) return err;
+    if (err>0) return ERROR(srcSize_wrong);
+    return ZSTD_estimateDStreamSize(fh.windowSize);
 }
 
 
@@ -2196,44 +2287,55 @@ size_t ZSTD_decompressStream(ZSTD_DStream* zds, ZSTD_outBuffer* output, ZSTD_inB
     char* op = ostart;
     U32 someMoreWork = 1;
 
+    DEBUGLOG(5, "ZSTD_decompressStream");
+    DEBUGLOG(5, "input size : %u", (U32)(input->size - input->pos));
 #if defined(ZSTD_LEGACY_SUPPORT) && (ZSTD_LEGACY_SUPPORT>=1)
-    if (zds->legacyVersion)
+    if (zds->legacyVersion) {
+        /* legacy support is incompatible with static dctx */
+        if (zds->staticSize) return ERROR(memory_allocation);
         return ZSTD_decompressLegacyStream(zds->legacyContext, zds->legacyVersion, output, input);
+    }
 #endif
 
     while (someMoreWork) {
-        switch(zds->stage)
+        switch(zds->streamStage)
         {
         case zdss_init :
             ZSTD_resetDStream(zds);   /* transparent reset on starting decoding a new frame */
             /* fall-through */
 
         case zdss_loadHeader :
-            {   size_t const hSize = ZSTD_getFrameParams(&zds->fParams, zds->headerBuffer, zds->lhSize);
-                if (ZSTD_isError(hSize))
+            {   size_t const hSize = ZSTD_getFrameHeader(&zds->fParams, zds->headerBuffer, zds->lhSize);
+                if (ZSTD_isError(hSize)) {
 #if defined(ZSTD_LEGACY_SUPPORT) && (ZSTD_LEGACY_SUPPORT>=1)
-                {   U32 const legacyVersion = ZSTD_isLegacy(istart, iend-istart);
+                    U32 const legacyVersion = ZSTD_isLegacy(istart, iend-istart);
                     if (legacyVersion) {
                         const void* const dict = zds->ddict ? zds->ddict->dictContent : NULL;
                         size_t const dictSize = zds->ddict ? zds->ddict->dictSize : 0;
+                        /* legacy support is incompatible with static dctx */
+                        if (zds->staticSize) return ERROR(memory_allocation);
                         CHECK_F(ZSTD_initLegacyStream(&zds->legacyContext, zds->previousLegacyVersion, legacyVersion,
                                                        dict, dictSize));
                         zds->legacyVersion = zds->previousLegacyVersion = legacyVersion;
                         return ZSTD_decompressLegacyStream(zds->legacyContext, zds->legacyVersion, output, input);
                     } else {
                         return hSize; /* error */
-                }   }
+                    }
 #else
-                return hSize;
+                    return hSize;
 #endif
+                }
                 if (hSize != 0) {   /* need more input */
                     size_t const toLoad = hSize - zds->lhSize;   /* if hSize!=0, hSize > zds->lhSize */
                     if (toLoad > (size_t)(iend-ip)) {   /* not enough input to load full header */
-                        memcpy(zds->headerBuffer + zds->lhSize, ip, iend-ip);
-                        zds->lhSize += iend-ip;
+                        if (iend-ip > 0) {
+                            memcpy(zds->headerBuffer + zds->lhSize, ip, iend-ip);
+                            zds->lhSize += iend-ip;
+                        }
                         input->pos = input->size;
                         return (MAX(ZSTD_frameHeaderSize_min, hSize) - zds->lhSize) + ZSTD_blockHeaderSize;   /* remaining header bytes + next block header */
                     }
+                    assert(ip != NULL);
                     memcpy(zds->headerBuffer + zds->lhSize, ip, toLoad); zds->lhSize = hSize; ip += toLoad;
                     break;
             }   }
@@ -2243,74 +2345,90 @@ size_t ZSTD_decompressStream(ZSTD_DStream* zds, ZSTD_outBuffer* output, ZSTD_inB
                 && (U64)(size_t)(oend-op) >= zds->fParams.frameContentSize) {
                 size_t const cSize = ZSTD_findFrameCompressedSize(istart, iend-istart);
                 if (cSize <= (size_t)(iend-istart)) {
-                    size_t const decompressedSize = ZSTD_decompress_usingDDict(zds->dctx, op, oend-op, istart, cSize, zds->ddict);
+                    size_t const decompressedSize = ZSTD_decompress_usingDDict(zds, op, oend-op, istart, cSize, zds->ddict);
                     if (ZSTD_isError(decompressedSize)) return decompressedSize;
                     ip = istart + cSize;
                     op += decompressedSize;
-                    zds->dctx->expected = 0;
-                    zds->stage = zdss_init;
+                    zds->expected = 0;
+                    zds->streamStage = zdss_init;
                     someMoreWork = 0;
                     break;
             }   }
 
-            /* Consume header */
-            ZSTD_refDDict(zds->dctx, zds->ddict);
-            {   size_t const h1Size = ZSTD_nextSrcSizeToDecompress(zds->dctx);  /* == ZSTD_frameHeaderSize_prefix */
-                CHECK_F(ZSTD_decompressContinue(zds->dctx, NULL, 0, zds->headerBuffer, h1Size));
-                {   size_t const h2Size = ZSTD_nextSrcSizeToDecompress(zds->dctx);
-                    CHECK_F(ZSTD_decompressContinue(zds->dctx, NULL, 0, zds->headerBuffer+h1Size, h2Size));
-            }   }
+            /* Consume header (see ZSTDds_decodeFrameHeader) */
+            DEBUGLOG(4, "Consume header");
+            CHECK_F(ZSTD_decompressBegin_usingDDict(zds, zds->ddict));
+
+            if ((MEM_readLE32(zds->headerBuffer) & 0xFFFFFFF0U) == ZSTD_MAGIC_SKIPPABLE_START) {  /* skippable frame */
+                zds->expected = MEM_readLE32(zds->headerBuffer + 4);
+                zds->stage = ZSTDds_skipFrame;
+            } else {
+                CHECK_F(ZSTD_decodeFrameHeader(zds, zds->headerBuffer, zds->lhSize));
+                zds->expected = ZSTD_blockHeaderSize;
+                zds->stage = ZSTDds_decodeBlockHeader;
+            }
 
+            /* control buffer memory usage */
+            DEBUGLOG(4, "Control max buffer memory usage");
             zds->fParams.windowSize = MAX(zds->fParams.windowSize, 1U << ZSTD_WINDOWLOG_ABSOLUTEMIN);
             if (zds->fParams.windowSize > zds->maxWindowSize) return ERROR(frameParameter_windowTooLarge);
 
             /* Adapt buffer sizes to frame header instructions */
-            {   size_t const blockSize = MIN(zds->fParams.windowSize, ZSTD_BLOCKSIZE_ABSOLUTEMAX);
+            {   size_t const blockSize = MIN(zds->fParams.windowSize, ZSTD_BLOCKSIZE_MAX);
                 size_t const neededOutSize = zds->fParams.windowSize + blockSize + WILDCOPY_OVERLENGTH * 2;
                 zds->blockSize = blockSize;
-                if (zds->inBuffSize < blockSize) {
-                    ZSTD_free(zds->inBuff, zds->customMem);
-                    zds->inBuffSize = 0;
-                    zds->inBuff = (char*)ZSTD_malloc(blockSize, zds->customMem);
-                    if (zds->inBuff == NULL) return ERROR(memory_allocation);
+                if ((zds->inBuffSize < blockSize) || (zds->outBuffSize < neededOutSize)) {
+                    size_t const bufferSize = blockSize + neededOutSize;
+                    DEBUGLOG(4, "inBuff  : from %u to %u",
+                                (U32)zds->inBuffSize, (U32)blockSize);
+                    DEBUGLOG(4, "outBuff : from %u to %u",
+                                (U32)zds->outBuffSize, (U32)neededOutSize);
+                    if (zds->staticSize) {  /* static DCtx */
+                        DEBUGLOG(4, "staticSize : %u", (U32)zds->staticSize);
+                        assert(zds->staticSize >= sizeof(ZSTD_DCtx));  /* controlled at init */
+                        if (bufferSize > zds->staticSize - sizeof(ZSTD_DCtx))
+                            return ERROR(memory_allocation);
+                    } else {
+                        ZSTD_free(zds->inBuff, zds->customMem);
+                        zds->inBuffSize = 0;
+                        zds->outBuffSize = 0;
+                        zds->inBuff = (char*)ZSTD_malloc(bufferSize, zds->customMem);
+                        if (zds->inBuff == NULL) return ERROR(memory_allocation);
+                    }
                     zds->inBuffSize = blockSize;
-                }
-                if (zds->outBuffSize < neededOutSize) {
-                    ZSTD_free(zds->outBuff, zds->customMem);
-                    zds->outBuffSize = 0;
-                    zds->outBuff = (char*)ZSTD_malloc(neededOutSize, zds->customMem);
-                    if (zds->outBuff == NULL) return ERROR(memory_allocation);
+                    zds->outBuff = zds->inBuff + zds->inBuffSize;
                     zds->outBuffSize = neededOutSize;
             }   }
-            zds->stage = zdss_read;
+            zds->streamStage = zdss_read;
             /* pass-through */
 
         case zdss_read:
-            {   size_t const neededInSize = ZSTD_nextSrcSizeToDecompress(zds->dctx);
+            DEBUGLOG(5, "stage zdss_read");
+            {   size_t const neededInSize = ZSTD_nextSrcSizeToDecompress(zds);
+                DEBUGLOG(5, "neededInSize = %u", (U32)neededInSize);
                 if (neededInSize==0) {  /* end of frame */
-                    zds->stage = zdss_init;
+                    zds->streamStage = zdss_init;
                     someMoreWork = 0;
                     break;
                 }
                 if ((size_t)(iend-ip) >= neededInSize) {  /* decode directly from src */
-                    const int isSkipFrame = ZSTD_isSkipFrame(zds->dctx);
-                    size_t const decodedSize = ZSTD_decompressContinue(zds->dctx,
+                    int const isSkipFrame = ZSTD_isSkipFrame(zds);
+                    size_t const decodedSize = ZSTD_decompressContinue(zds,
                         zds->outBuff + zds->outStart, (isSkipFrame ? 0 : zds->outBuffSize - zds->outStart),
                         ip, neededInSize);
                     if (ZSTD_isError(decodedSize)) return decodedSize;
                     ip += neededInSize;
                     if (!decodedSize && !isSkipFrame) break;   /* this was just a header */
                     zds->outEnd = zds->outStart + decodedSize;
-                    zds->stage = zdss_flush;
+                    zds->streamStage = zdss_flush;
                     break;
-                }
-                if (ip==iend) { someMoreWork = 0; break; }   /* no more input */
-                zds->stage = zdss_load;
-                /* pass-through */
-            }
+            }   }
+            if (ip==iend) { someMoreWork = 0; break; }   /* no more input */
+            zds->streamStage = zdss_load;
+            /* pass-through */
 
         case zdss_load:
-            {   size_t const neededInSize = ZSTD_nextSrcSizeToDecompress(zds->dctx);
+            {   size_t const neededInSize = ZSTD_nextSrcSizeToDecompress(zds);
                 size_t const toLoad = neededInSize - zds->inPos;   /* should always be <= remaining space within inBuff */
                 size_t loadedSize;
                 if (toLoad > zds->inBuffSize - zds->inPos) return ERROR(corruption_detected);   /* should never happen */
@@ -2320,17 +2438,17 @@ size_t ZSTD_decompressStream(ZSTD_DStream* zds, ZSTD_outBuffer* output, ZSTD_inB
                 if (loadedSize < toLoad) { someMoreWork = 0; break; }   /* not enough input, wait for more */
 
                 /* decode loaded input */
-                {  const int isSkipFrame = ZSTD_isSkipFrame(zds->dctx);
-                   size_t const decodedSize = ZSTD_decompressContinue(zds->dctx,
+                {  const int isSkipFrame = ZSTD_isSkipFrame(zds);
+                   size_t const decodedSize = ZSTD_decompressContinue(zds,
                         zds->outBuff + zds->outStart, zds->outBuffSize - zds->outStart,
                         zds->inBuff, neededInSize);
                     if (ZSTD_isError(decodedSize)) return decodedSize;
                     zds->inPos = 0;   /* input is consumed */
-                    if (!decodedSize && !isSkipFrame) { zds->stage = zdss_read; break; }   /* this was just a header */
+                    if (!decodedSize && !isSkipFrame) { zds->streamStage = zdss_read; break; }   /* this was just a header */
                     zds->outEnd = zds->outStart +  decodedSize;
-                    zds->stage = zdss_flush;
-                    /* pass-through */
             }   }
+            zds->streamStage = zdss_flush;
+            /* pass-through */
 
         case zdss_flush:
             {   size_t const toFlushSize = zds->outEnd - zds->outStart;
@@ -2338,37 +2456,41 @@ size_t ZSTD_decompressStream(ZSTD_DStream* zds, ZSTD_outBuffer* output, ZSTD_inB
                 op += flushedSize;
                 zds->outStart += flushedSize;
                 if (flushedSize == toFlushSize) {  /* flush completed */
-                    zds->stage = zdss_read;
+                    zds->streamStage = zdss_read;
                     if (zds->outStart + zds->blockSize > zds->outBuffSize)
                         zds->outStart = zds->outEnd = 0;
                     break;
-                }
-                /* cannot complete flush */
-                someMoreWork = 0;
-                break;
-            }
+            }   }
+            /* cannot complete flush */
+            someMoreWork = 0;
+            break;
+
         default: return ERROR(GENERIC);   /* impossible */
     }   }
 
     /* result */
     input->pos += (size_t)(ip-istart);
     output->pos += (size_t)(op-ostart);
-    {   size_t nextSrcSizeHint = ZSTD_nextSrcSizeToDecompress(zds->dctx);
+    {   size_t nextSrcSizeHint = ZSTD_nextSrcSizeToDecompress(zds);
         if (!nextSrcSizeHint) {   /* frame fully decoded */
             if (zds->outEnd == zds->outStart) {  /* output fully flushed */
                 if (zds->hostageByte) {
-                    if (input->pos >= input->size) { zds->stage = zdss_read; return 1; }  /* can't release hostage (not present) */
+                    if (input->pos >= input->size) {
+                        /* can't release hostage (not present) */
+                        zds->streamStage = zdss_read;
+                        return 1;
+                    }
                     input->pos++;  /* release hostage */
-                }
+                }   /* zds->hostageByte */
                 return 0;
-            }
+            }  /* zds->outEnd == zds->outStart */
             if (!zds->hostageByte) { /* output not fully flushed; keep last byte as hostage; will be released when all output is flushed */
                 input->pos--;   /* note : pos > 0, otherwise, impossible to finish reading last block */
                 zds->hostageByte=1;
             }
             return 1;
-        }
-        nextSrcSizeHint += ZSTD_blockHeaderSize * (ZSTD_nextInputType(zds->dctx) == ZSTDnit_block);   /* preload header of next block */
+        }  /* nextSrcSizeHint==0 */
+        nextSrcSizeHint += ZSTD_blockHeaderSize * (ZSTD_nextInputType(zds) == ZSTDnit_block);   /* preload header of next block */
         if (zds->inPos > nextSrcSizeHint) return ERROR(GENERIC);   /* should never happen */
         nextSrcSizeHint -= zds->inPos;   /* already loaded*/
         return nextSrcSizeHint;
diff --git a/thirdparty/zstd/zstd.h b/thirdparty/zstd/zstd.h
index f8050c1361..58e9a5606d 100644
--- a/thirdparty/zstd/zstd.h
+++ b/thirdparty/zstd/zstd.h
@@ -19,10 +19,12 @@ extern "C" {
 
 
 /* =====   ZSTDLIB_API : control library symbols visibility   ===== */
-#if defined(__GNUC__) && (__GNUC__ >= 4)
-#  define ZSTDLIB_VISIBILITY __attribute__ ((visibility ("default")))
-#else
-#  define ZSTDLIB_VISIBILITY
+#ifndef ZSTDLIB_VISIBILITY
+#  if defined(__GNUC__) && (__GNUC__ >= 4)
+#    define ZSTDLIB_VISIBILITY __attribute__ ((visibility ("default")))
+#  else
+#    define ZSTDLIB_VISIBILITY
+#  endif
 #endif
 #if defined(ZSTD_DLL_EXPORT) && (ZSTD_DLL_EXPORT==1)
 #  define ZSTDLIB_API __declspec(dllexport) ZSTDLIB_VISIBILITY
@@ -36,35 +38,37 @@ extern "C" {
 /*******************************************************************************************************
   Introduction
 
-  zstd, short for Zstandard, is a fast lossless compression algorithm, targeting real-time compression scenarios
-  at zlib-level and better compression ratios. The zstd compression library provides in-memory compression and
-  decompression functions. The library supports compression levels from 1 up to ZSTD_maxCLevel() which is 22.
+  zstd, short for Zstandard, is a fast lossless compression algorithm,
+  targeting real-time compression scenarios at zlib-level and better compression ratios.
+  The zstd compression library provides in-memory compression and decompression functions.
+  The library supports compression levels from 1 up to ZSTD_maxCLevel() which is currently 22.
   Levels >= 20, labeled `--ultra`, should be used with caution, as they require more memory.
   Compression can be done in:
     - a single step (described as Simple API)
     - a single step, reusing a context (described as Explicit memory management)
     - unbounded multiple steps (described as Streaming compression)
-  The compression ratio achievable on small data can be highly improved using compression with a dictionary in:
+  The compression ratio achievable on small data can be highly improved using a dictionary in:
     - a single step (described as Simple dictionary API)
     - a single step, reusing a dictionary (described as Fast dictionary API)
 
   Advanced experimental functions can be accessed using #define ZSTD_STATIC_LINKING_ONLY before including zstd.h.
-  These APIs shall never be used with a dynamic library.
+  Advanced experimental APIs shall never be used with a dynamic library.
   They are not "stable", their definition may change in the future. Only static linking is allowed.
 *********************************************************************************************************/
 
 /*------   Version   ------*/
 #define ZSTD_VERSION_MAJOR    1
-#define ZSTD_VERSION_MINOR    2
+#define ZSTD_VERSION_MINOR    3
 #define ZSTD_VERSION_RELEASE  0
 
+#define ZSTD_VERSION_NUMBER  (ZSTD_VERSION_MAJOR *100*100 + ZSTD_VERSION_MINOR *100 + ZSTD_VERSION_RELEASE)
+ZSTDLIB_API unsigned ZSTD_versionNumber(void);   /**< useful to check dll version */
+
 #define ZSTD_LIB_VERSION ZSTD_VERSION_MAJOR.ZSTD_VERSION_MINOR.ZSTD_VERSION_RELEASE
 #define ZSTD_QUOTE(str) #str
 #define ZSTD_EXPAND_AND_QUOTE(str) ZSTD_QUOTE(str)
 #define ZSTD_VERSION_STRING ZSTD_EXPAND_AND_QUOTE(ZSTD_LIB_VERSION)
-
-#define ZSTD_VERSION_NUMBER  (ZSTD_VERSION_MAJOR *100*100 + ZSTD_VERSION_MINOR *100 + ZSTD_VERSION_RELEASE)
-ZSTDLIB_API unsigned ZSTD_versionNumber(void);   /**< library version number; to be used when checking dll version */
+ZSTDLIB_API const char* ZSTD_versionString(void);   /* v1.3.0 */
 
 
 /***************************************
@@ -81,38 +85,48 @@ ZSTDLIB_API size_t ZSTD_compress( void* dst, size_t dstCapacity,
 
 /*! ZSTD_decompress() :
  *  `compressedSize` : must be the _exact_ size of some number of compressed and/or skippable frames.
- *  `dstCapacity` is an upper bound of originalSize.
+ *  `dstCapacity` is an upper bound of originalSize to regenerate.
  *  If user cannot imply a maximum upper bound, it's better to use streaming mode to decompress data.
  *  @return : the number of bytes decompressed into `dst` (<= `dstCapacity`),
  *            or an errorCode if it fails (which can be tested using ZSTD_isError()). */
 ZSTDLIB_API size_t ZSTD_decompress( void* dst, size_t dstCapacity,
                               const void* src, size_t compressedSize);
 
-/*! ZSTD_getDecompressedSize() :
- *  NOTE: This function is planned to be obsolete, in favour of ZSTD_getFrameContentSize.
- *  ZSTD_getFrameContentSize functions the same way, returning the decompressed size of a single
- *  frame, but distinguishes empty frames from frames with an unknown size, or errors.
- *
- *  Additionally, ZSTD_findDecompressedSize can be used instead.  It can handle multiple
- *  concatenated frames in one buffer, and so is more general.
- *  As a result however, it requires more computation and entire frames to be passed to it,
- *  as opposed to ZSTD_getFrameContentSize which requires only a single frame's header.
- *
- *  'src' is the start of a zstd compressed frame.
- *  @return : content size to be decompressed, as a 64-bits value _if known_, 0 otherwise.
- *   note 1 : decompressed size is an optional field, that may not be present, especially in streaming mode.
- *            When `return==0`, data to decompress could be any size.
+/*! ZSTD_getFrameContentSize() : v1.3.0
+ *  `src` should point to the start of a ZSTD encoded frame.
+ *  `srcSize` must be at least as large as the frame header.
+ *            hint : any size >= `ZSTD_frameHeaderSize_max` is large enough.
+ *  @return : - decompressed size of the frame in `src`, if known
+ *            - ZSTD_CONTENTSIZE_UNKNOWN if the size cannot be determined
+ *            - ZSTD_CONTENTSIZE_ERROR if an error occurred (e.g. invalid magic number, srcSize too small)
+ *   note 1 : a 0 return value means the frame is valid but "empty".
+ *   note 2 : decompressed size is an optional field, it may not be present, typically in streaming mode.
+ *            When `return==ZSTD_CONTENTSIZE_UNKNOWN`, data to decompress could be any size.
  *            In which case, it's necessary to use streaming mode to decompress data.
- *            Optionally, application can still use ZSTD_decompress() while relying on implied limits.
- *            (For example, data may be necessarily cut into blocks <= 16 KB).
- *   note 2 : decompressed size is always present when compression is done with ZSTD_compress()
- *   note 3 : decompressed size can be very large (64-bits value),
+ *            Optionally, application can rely on some implicit limit,
+ *            as ZSTD_decompress() only needs an upper bound of decompressed size.
+ *            (For example, data could be necessarily cut into blocks <= 16 KB).
+ *   note 3 : decompressed size is always present when compression is done with ZSTD_compress()
+ *   note 4 : decompressed size can be very large (64-bits value),
  *            potentially larger than what local system can handle as a single memory segment.
  *            In which case, it's necessary to use streaming mode to decompress data.
- *   note 4 : If source is untrusted, decompressed size could be wrong or intentionally modified.
- *            Always ensure result fits within application's authorized limits.
+ *   note 5 : If source is untrusted, decompressed size could be wrong or intentionally modified.
+ *            Always ensure return value fits within application's authorized limits.
  *            Each application can set its own limits.
- *   note 5 : when `return==0`, if precise failure cause is needed, use ZSTD_getFrameParams() to know more. */
+ *   note 6 : This function replaces ZSTD_getDecompressedSize() */
+#define ZSTD_CONTENTSIZE_UNKNOWN (0ULL - 1)
+#define ZSTD_CONTENTSIZE_ERROR   (0ULL - 2)
+ZSTDLIB_API unsigned long long ZSTD_getFrameContentSize(const void *src, size_t srcSize);
+
+/*! ZSTD_getDecompressedSize() :
+ *  NOTE: This function is now obsolete, in favor of ZSTD_getFrameContentSize().
+ *  Both functions work the same way,
+ *  but ZSTD_getDecompressedSize() blends
+ *  "empty", "unknown" and "error" results in the same return value (0),
+ *  while ZSTD_getFrameContentSize() distinguishes them.
+ *
+ *  'src' is the start of a zstd compressed frame.
+ *  @return : content size to be decompressed, as a 64-bits value _if known and not empty_, 0 otherwise. */
 ZSTDLIB_API unsigned long long ZSTD_getDecompressedSize(const void* src, size_t srcSize);
 
 
@@ -137,29 +151,35 @@ ZSTDLIB_API size_t     ZSTD_freeCCtx(ZSTD_CCtx* cctx);
 
 /*! ZSTD_compressCCtx() :
  *  Same as ZSTD_compress(), requires an allocated ZSTD_CCtx (see ZSTD_createCCtx()). */
-ZSTDLIB_API size_t ZSTD_compressCCtx(ZSTD_CCtx* ctx, void* dst, size_t dstCapacity, const void* src, size_t srcSize, int compressionLevel);
+ZSTDLIB_API size_t ZSTD_compressCCtx(ZSTD_CCtx* ctx,
+                                     void* dst, size_t dstCapacity,
+                               const void* src, size_t srcSize,
+                                     int compressionLevel);
 
 /*= Decompression context
  *  When decompressing many times,
- *  it is recommended to allocate a context just once, and re-use it for each successive compression operation.
+ *  it is recommended to allocate a context only once,
+ *  and re-use it for each successive compression operation.
  *  This will make workload friendlier for system's memory.
- *  Use one context per thread for parallel execution in multi-threaded environments. */
+ *  Use one context per thread for parallel execution. */
 typedef struct ZSTD_DCtx_s ZSTD_DCtx;
 ZSTDLIB_API ZSTD_DCtx* ZSTD_createDCtx(void);
 ZSTDLIB_API size_t     ZSTD_freeDCtx(ZSTD_DCtx* dctx);
 
 /*! ZSTD_decompressDCtx() :
- *  Same as ZSTD_decompress(), requires an allocated ZSTD_DCtx (see ZSTD_createDCtx()). */
-ZSTDLIB_API size_t ZSTD_decompressDCtx(ZSTD_DCtx* ctx, void* dst, size_t dstCapacity, const void* src, size_t srcSize);
+ *  Same as ZSTD_decompress(), requires an allocated ZSTD_DCtx (see ZSTD_createDCtx()) */
+ZSTDLIB_API size_t ZSTD_decompressDCtx(ZSTD_DCtx* ctx,
+                                       void* dst, size_t dstCapacity,
+                                 const void* src, size_t srcSize);
 
 
 /**************************
 *  Simple dictionary API
 ***************************/
 /*! ZSTD_compress_usingDict() :
-*   Compression using a predefined Dictionary (see dictBuilder/zdict.h).
-*   Note : This function loads the dictionary, resulting in significant startup delay.
-*   Note : When `dict == NULL || dictSize < 8` no dictionary is used. */
+ *  Compression using a predefined Dictionary (see dictBuilder/zdict.h).
+ *  Note : This function loads the dictionary, resulting in significant startup delay.
+ *  Note : When `dict == NULL || dictSize < 8` no dictionary is used. */
 ZSTDLIB_API size_t ZSTD_compress_usingDict(ZSTD_CCtx* ctx,
                                            void* dst, size_t dstCapacity,
                                      const void* src, size_t srcSize,
@@ -167,30 +187,31 @@ ZSTDLIB_API size_t ZSTD_compress_usingDict(ZSTD_CCtx* ctx,
                                            int compressionLevel);
 
 /*! ZSTD_decompress_usingDict() :
-*   Decompression using a predefined Dictionary (see dictBuilder/zdict.h).
-*   Dictionary must be identical to the one used during compression.
-*   Note : This function loads the dictionary, resulting in significant startup delay.
-*   Note : When `dict == NULL || dictSize < 8` no dictionary is used. */
+ *  Decompression using a predefined Dictionary (see dictBuilder/zdict.h).
+ *  Dictionary must be identical to the one used during compression.
+ *  Note : This function loads the dictionary, resulting in significant startup delay.
+ *  Note : When `dict == NULL || dictSize < 8` no dictionary is used. */
 ZSTDLIB_API size_t ZSTD_decompress_usingDict(ZSTD_DCtx* dctx,
                                              void* dst, size_t dstCapacity,
                                        const void* src, size_t srcSize,
                                        const void* dict,size_t dictSize);
 
 
-/****************************
-*  Fast dictionary API
-****************************/
+/**********************************
+ *  Bulk processing dictionary API
+ *********************************/
 typedef struct ZSTD_CDict_s ZSTD_CDict;
 
 /*! ZSTD_createCDict() :
-*   When compressing multiple messages / blocks with the same dictionary, it's recommended to load it just once.
-*   ZSTD_createCDict() will create a digested dictionary, ready to start future compression operations without startup delay.
-*   ZSTD_CDict can be created once and used by multiple threads concurrently, as its usage is read-only.
-*   `dictBuffer` can be released after ZSTD_CDict creation, as its content is copied within CDict */
-ZSTDLIB_API ZSTD_CDict* ZSTD_createCDict(const void* dictBuffer, size_t dictSize, int compressionLevel);
+ *  When compressing multiple messages / blocks with the same dictionary, it's recommended to load it just once.
+ *  ZSTD_createCDict() will create a digested dictionary, ready to start future compression operations without startup delay.
+ *  ZSTD_CDict can be created once and shared by multiple threads concurrently, since its usage is read-only.
+ *  `dictBuffer` can be released after ZSTD_CDict creation, since its content is copied within CDict */
+ZSTDLIB_API ZSTD_CDict* ZSTD_createCDict(const void* dictBuffer, size_t dictSize,
+                                         int compressionLevel);
 
 /*! ZSTD_freeCDict() :
-*   Function frees memory allocated by ZSTD_createCDict(). */
+ *  Function frees memory allocated by ZSTD_createCDict(). */
 ZSTDLIB_API size_t      ZSTD_freeCDict(ZSTD_CDict* CDict);
 
 /*! ZSTD_compress_usingCDict() :
@@ -207,17 +228,17 @@ ZSTDLIB_API size_t ZSTD_compress_usingCDict(ZSTD_CCtx* cctx,
 typedef struct ZSTD_DDict_s ZSTD_DDict;
 
 /*! ZSTD_createDDict() :
-*   Create a digested dictionary, ready to start decompression operation without startup delay.
-*   dictBuffer can be released after DDict creation, as its content is copied inside DDict */
+ *  Create a digested dictionary, ready to start decompression operation without startup delay.
+ *  dictBuffer can be released after DDict creation, as its content is copied inside DDict */
 ZSTDLIB_API ZSTD_DDict* ZSTD_createDDict(const void* dictBuffer, size_t dictSize);
 
 /*! ZSTD_freeDDict() :
-*   Function frees memory allocated with ZSTD_createDDict() */
+ *  Function frees memory allocated with ZSTD_createDDict() */
 ZSTDLIB_API size_t      ZSTD_freeDDict(ZSTD_DDict* ddict);
 
 /*! ZSTD_decompress_usingDDict() :
-*   Decompression using a digested Dictionary.
-*   Faster startup than ZSTD_decompress_usingDict(), recommended when same dictionary is used multiple times. */
+ *  Decompression using a digested Dictionary.
+ *  Faster startup than ZSTD_decompress_usingDict(), recommended when same dictionary is used multiple times. */
 ZSTDLIB_API size_t ZSTD_decompress_usingDDict(ZSTD_DCtx* dctx,
                                               void* dst, size_t dstCapacity,
                                         const void* src, size_t srcSize,
@@ -274,14 +295,17 @@ typedef struct ZSTD_outBuffer_s {
 *  ZSTD_endStream() instructs to finish a frame.
 *  It will perform a flush and write frame epilogue.
 *  The epilogue is required for decoders to consider a frame completed.
-*  Similar to ZSTD_flushStream(), it may not be able to flush the full content if `output->size` is too small.
+*  ZSTD_endStream() may not be able to flush full data if `output->size` is too small.
 *  In which case, call again ZSTD_endStream() to complete the flush.
-*  @return : nb of bytes still present within internal buffer (0 if it's empty, hence compression completed)
+*  @return : 0 if frame fully completed and fully flushed,
+             or >0 if some data is still present within internal buffer
+                  (value is minimum size estimation for remaining data to flush, but it could be more)
 *            or an error code, which can be tested using ZSTD_isError().
 *
 * *******************************************************************/
 
-typedef struct ZSTD_CStream_s ZSTD_CStream;
+typedef ZSTD_CCtx ZSTD_CStream;  /**< CCtx and CStream are now effectively same object (>= v1.3.0) */
+                                 /* Continue to distinguish them for compatibility with versions <= v1.2.0 */
 /*===== ZSTD_CStream management functions =====*/
 ZSTDLIB_API ZSTD_CStream* ZSTD_createCStream(void);
 ZSTDLIB_API size_t ZSTD_freeCStream(ZSTD_CStream* zcs);
@@ -319,7 +343,8 @@ ZSTDLIB_API size_t ZSTD_CStreamOutSize(void);   /**< recommended size for output
 *            The return value is a suggested next input size (a hint to improve latency) that will never load more than the current frame.
 * *******************************************************************************/
 
-typedef struct ZSTD_DStream_s ZSTD_DStream;
+typedef ZSTD_DCtx ZSTD_DStream;  /**< DCtx and DStream are now effectively same object (>= v1.3.0) */
+                                 /* Continue to distinguish them for compatibility with versions <= v1.2.0 */
 /*===== ZSTD_DStream management functions =====*/
 ZSTDLIB_API ZSTD_DStream* ZSTD_createDStream(void);
 ZSTDLIB_API size_t ZSTD_freeDStream(ZSTD_DStream* zds);
@@ -334,23 +359,22 @@ ZSTDLIB_API size_t ZSTD_DStreamOutSize(void);   /*!< recommended size for output
 #endif  /* ZSTD_H_235446 */
 
 
-#if defined(ZSTD_STATIC_LINKING_ONLY) && !defined(ZSTD_H_ZSTD_STATIC_LINKING_ONLY)
-#define ZSTD_H_ZSTD_STATIC_LINKING_ONLY
 
 /****************************************************************************************
  * START OF ADVANCED AND EXPERIMENTAL FUNCTIONS
  * The definitions in this section are considered experimental.
- * They should never be used with a dynamic library, as they may change in the future.
- * They are provided for advanced usages.
+ * They should never be used with a dynamic library, as prototypes may change in the future.
+ * They are provided for advanced scenarios.
  * Use them only in association with static linking.
  * ***************************************************************************************/
 
+#if defined(ZSTD_STATIC_LINKING_ONLY) && !defined(ZSTD_H_ZSTD_STATIC_LINKING_ONLY)
+#define ZSTD_H_ZSTD_STATIC_LINKING_ONLY
+
 /* --- Constants ---*/
 #define ZSTD_MAGICNUMBER            0xFD2FB528   /* >= v0.8.0 */
 #define ZSTD_MAGIC_SKIPPABLE_START  0x184D2A50U
-
-#define ZSTD_CONTENTSIZE_UNKNOWN (0ULL - 1)
-#define ZSTD_CONTENTSIZE_ERROR   (0ULL - 2)
+#define ZSTD_MAGIC_DICTIONARY       0xEC30A437   /* v0.7+ */
 
 #define ZSTD_WINDOWLOG_MAX_32  27
 #define ZSTD_WINDOWLOG_MAX_64  27
@@ -370,14 +394,15 @@ ZSTDLIB_API size_t ZSTD_DStreamOutSize(void);   /*!< recommended size for output
 
 #define ZSTD_FRAMEHEADERSIZE_MAX 18    /* for static allocation */
 #define ZSTD_FRAMEHEADERSIZE_MIN  6
-static const size_t ZSTD_frameHeaderSize_prefix = 5;
-static const size_t ZSTD_frameHeaderSize_min = ZSTD_FRAMEHEADERSIZE_MIN;
+static const size_t ZSTD_frameHeaderSize_prefix = 5;  /* minimum input size to know frame header size */
 static const size_t ZSTD_frameHeaderSize_max = ZSTD_FRAMEHEADERSIZE_MAX;
+static const size_t ZSTD_frameHeaderSize_min = ZSTD_FRAMEHEADERSIZE_MIN;
 static const size_t ZSTD_skippableHeaderSize = 8;  /* magic number + skippable frame length */
 
 
 /*--- Advanced types ---*/
-typedef enum { ZSTD_fast, ZSTD_dfast, ZSTD_greedy, ZSTD_lazy, ZSTD_lazy2, ZSTD_btlazy2, ZSTD_btopt, ZSTD_btopt2 } ZSTD_strategy;   /* from faster to stronger */
+typedef enum { ZSTD_fast=1, ZSTD_dfast, ZSTD_greedy, ZSTD_lazy, ZSTD_lazy2,
+               ZSTD_btlazy2, ZSTD_btopt, ZSTD_btultra } ZSTD_strategy;   /* from faster to stronger */
 
 typedef struct {
     unsigned windowLog;      /**< largest match distance : larger == more compression, more memory needed during decompression */
@@ -400,76 +425,141 @@ typedef struct {
     ZSTD_frameParameters fParams;
 } ZSTD_parameters;
 
+typedef struct {
+    unsigned long long frameContentSize;
+    size_t windowSize;
+    unsigned dictID;
+    unsigned checksumFlag;
+} ZSTD_frameHeader;
+
 /*= Custom memory allocation functions */
 typedef void* (*ZSTD_allocFunction) (void* opaque, size_t size);
 typedef void  (*ZSTD_freeFunction) (void* opaque, void* address);
 typedef struct { ZSTD_allocFunction customAlloc; ZSTD_freeFunction customFree; void* opaque; } ZSTD_customMem;
+/* use this constant to defer to stdlib's functions */
+static const ZSTD_customMem ZSTD_defaultCMem = { NULL, NULL, NULL };
+
 
 /***************************************
-*  Compressed size functions
+*  Frame size functions
 ***************************************/
 
 /*! ZSTD_findFrameCompressedSize() :
  *  `src` should point to the start of a ZSTD encoded frame or skippable frame
  *  `srcSize` must be at least as large as the frame
- *  @return : the compressed size of the frame pointed to by `src`, suitable to pass to
- *      `ZSTD_decompress` or similar, or an error code if given invalid input. */
+ *  @return : the compressed size of the first frame starting at `src`,
+ *            suitable to pass to `ZSTD_decompress` or similar,
+ *            or an error code if input is invalid */
 ZSTDLIB_API size_t ZSTD_findFrameCompressedSize(const void* src, size_t srcSize);
 
+/*! ZSTD_findDecompressedSize() :
+ *  `src` should point the start of a series of ZSTD encoded and/or skippable frames
+ *  `srcSize` must be the _exact_ size of this series
+ *       (i.e. there should be a frame boundary exactly at `srcSize` bytes after `src`)
+ *  @return : - decompressed size of all data in all successive frames
+ *            - if the decompressed size cannot be determined: ZSTD_CONTENTSIZE_UNKNOWN
+ *            - if an error occurred: ZSTD_CONTENTSIZE_ERROR
+ *
+ *   note 1 : decompressed size is an optional field, that may not be present, especially in streaming mode.
+ *            When `return==ZSTD_CONTENTSIZE_UNKNOWN`, data to decompress could be any size.
+ *            In which case, it's necessary to use streaming mode to decompress data.
+ *   note 2 : decompressed size is always present when compression is done with ZSTD_compress()
+ *   note 3 : decompressed size can be very large (64-bits value),
+ *            potentially larger than what local system can handle as a single memory segment.
+ *            In which case, it's necessary to use streaming mode to decompress data.
+ *   note 4 : If source is untrusted, decompressed size could be wrong or intentionally modified.
+ *            Always ensure result fits within application's authorized limits.
+ *            Each application can set its own limits.
+ *   note 5 : ZSTD_findDecompressedSize handles multiple frames, and so it must traverse the input to
+ *            read each contained frame header.  This is fast as most of the data is skipped,
+ *            however it does mean that all frame data must be present and valid. */
+ZSTDLIB_API unsigned long long ZSTD_findDecompressedSize(const void* src, size_t srcSize);
+
+/*! ZSTD_frameHeaderSize() :
+*   `src` should point to the start of a ZSTD frame
+*   `srcSize` must be >= ZSTD_frameHeaderSize_prefix.
+*   @return : size of the Frame Header */
+ZSTDLIB_API size_t ZSTD_frameHeaderSize(const void* src, size_t srcSize);
+
+
 /***************************************
-*  Decompressed size functions
+*  Context memory usage
 ***************************************/
-/*! ZSTD_getFrameContentSize() :
-*   `src` should point to the start of a ZSTD encoded frame
-*   `srcSize` must be at least as large as the frame header.  A value greater than or equal
-*       to `ZSTD_frameHeaderSize_max` is guaranteed to be large enough in all cases.
-*   @return : decompressed size of the frame pointed to be `src` if known, otherwise
-*             - ZSTD_CONTENTSIZE_UNKNOWN if the size cannot be determined
-*             - ZSTD_CONTENTSIZE_ERROR if an error occurred (e.g. invalid magic number, srcSize too small) */
-ZSTDLIB_API unsigned long long ZSTD_getFrameContentSize(const void *src, size_t srcSize);
 
-/*! ZSTD_findDecompressedSize() :
-*   `src` should point the start of a series of ZSTD encoded and/or skippable frames
-*   `srcSize` must be the _exact_ size of this series
-*       (i.e. there should be a frame boundary exactly `srcSize` bytes after `src`)
-*   @return : the decompressed size of all data in the contained frames, as a 64-bit value _if known_
-*             - if the decompressed size cannot be determined: ZSTD_CONTENTSIZE_UNKNOWN
-*             - if an error occurred: ZSTD_CONTENTSIZE_ERROR
-*
-*    note 1 : decompressed size is an optional field, that may not be present, especially in streaming mode.
-*             When `return==ZSTD_CONTENTSIZE_UNKNOWN`, data to decompress could be any size.
-*             In which case, it's necessary to use streaming mode to decompress data.
-*             Optionally, application can still use ZSTD_decompress() while relying on implied limits.
-*             (For example, data may be necessarily cut into blocks <= 16 KB).
-*    note 2 : decompressed size is always present when compression is done with ZSTD_compress()
-*    note 3 : decompressed size can be very large (64-bits value),
-*             potentially larger than what local system can handle as a single memory segment.
-*             In which case, it's necessary to use streaming mode to decompress data.
-*    note 4 : If source is untrusted, decompressed size could be wrong or intentionally modified.
-*             Always ensure result fits within application's authorized limits.
-*             Each application can set its own limits.
-*    note 5 : ZSTD_findDecompressedSize handles multiple frames, and so it must traverse the input to
-*             read each contained frame header.  This is efficient as most of the data is skipped,
-*             however it does mean that all frame data must be present and valid. */
-ZSTDLIB_API unsigned long long ZSTD_findDecompressedSize(const void* src, size_t srcSize);
+/*! ZSTD_sizeof_*() :
+ *  These functions give the current memory usage of selected object.
+ *  Object memory usage can evolve if it's re-used multiple times. */
+ZSTDLIB_API size_t ZSTD_sizeof_CCtx(const ZSTD_CCtx* cctx);
+ZSTDLIB_API size_t ZSTD_sizeof_DCtx(const ZSTD_DCtx* dctx);
+ZSTDLIB_API size_t ZSTD_sizeof_CStream(const ZSTD_CStream* zcs);
+ZSTDLIB_API size_t ZSTD_sizeof_DStream(const ZSTD_DStream* zds);
+ZSTDLIB_API size_t ZSTD_sizeof_CDict(const ZSTD_CDict* cdict);
+ZSTDLIB_API size_t ZSTD_sizeof_DDict(const ZSTD_DDict* ddict);
+
+/*! ZSTD_estimate*() :
+ *  These functions make it possible to estimate memory usage
+ *  of a future {D,C}Ctx, before its creation.
+ *  ZSTD_estimateCCtxSize() will provide a budget large enough for any compression level up to selected one.
+ *  It will also consider src size to be arbitrarily "large", which is worst case.
+ *  If srcSize is known to always be small, ZSTD_estimateCCtxSize_advanced() can provide a tighter estimation.
+ *  ZSTD_estimateCCtxSize_advanced() can be used in tandem with ZSTD_getCParams() to create cParams from compressionLevel.
+ *  Note : CCtx estimation is only correct for single-threaded compression */
+ZSTDLIB_API size_t ZSTD_estimateCCtxSize(int compressionLevel);
+ZSTDLIB_API size_t ZSTD_estimateCCtxSize_advanced(ZSTD_compressionParameters cParams);
+ZSTDLIB_API size_t ZSTD_estimateDCtxSize(void);
+
+/*! ZSTD_estimate?StreamSize() :
+ *  ZSTD_estimateCStreamSize() will provide a budget large enough for any compression level up to selected one.
+ *  It will also consider src size to be arbitrarily "large", which is worst case.
+ *  If srcSize is known to always be small, ZSTD_estimateCStreamSize_advanced() can provide a tighter estimation.
+ *  ZSTD_estimateCStreamSize_advanced() can be used in tandem with ZSTD_getCParams() to create cParams from compressionLevel.
+ *  Note : CStream estimation is only correct for single-threaded compression.
+ *  ZSTD_DStream memory budget depends on window Size.
+ *  This information can be passed manually, using ZSTD_estimateDStreamSize,
+ *  or deducted from a valid frame Header, using ZSTD_estimateDStreamSize_fromFrame();
+ *  Note : if streaming is init with function ZSTD_init?Stream_usingDict(),
+ *         an internal ?Dict will be created, which additional size is not estimated here.
+ *         In this case, get total size by adding ZSTD_estimate?DictSize */
+ZSTDLIB_API size_t ZSTD_estimateCStreamSize(int compressionLevel);
+ZSTDLIB_API size_t ZSTD_estimateCStreamSize_advanced(ZSTD_compressionParameters cParams);
+ZSTDLIB_API size_t ZSTD_estimateDStreamSize(size_t windowSize);
+ZSTDLIB_API size_t ZSTD_estimateDStreamSize_fromFrame(const void* src, size_t srcSize);
+
+/*! ZSTD_estimate?DictSize() :
+ *  ZSTD_estimateCDictSize() will bet that src size is relatively "small", and content is copied, like ZSTD_createCDict().
+ *  ZSTD_estimateCStreamSize_advanced() makes it possible to control precisely compression parameters, like ZSTD_createCDict_advanced().
+ *  Note : dictionary created "byReference" are smaller */
+ZSTDLIB_API size_t ZSTD_estimateCDictSize(size_t dictSize, int compressionLevel);
+ZSTDLIB_API size_t ZSTD_estimateCDictSize_advanced(size_t dictSize, ZSTD_compressionParameters cParams, unsigned byReference);
+ZSTDLIB_API size_t ZSTD_estimateDDictSize(size_t dictSize, unsigned byReference);
 
 
 /***************************************
 *  Advanced compression functions
 ***************************************/
-/*! ZSTD_estimateCCtxSize() :
- *  Gives the amount of memory allocated for a ZSTD_CCtx given a set of compression parameters.
- *  `frameContentSize` is an optional parameter, provide `0` if unknown */
-ZSTDLIB_API size_t ZSTD_estimateCCtxSize(ZSTD_compressionParameters cParams);
-
 /*! ZSTD_createCCtx_advanced() :
  *  Create a ZSTD compression context using external alloc and free functions */
 ZSTDLIB_API ZSTD_CCtx* ZSTD_createCCtx_advanced(ZSTD_customMem customMem);
 
-/*! ZSTD_sizeofCCtx() :
- *  Gives the amount of memory used by a given ZSTD_CCtx */
-ZSTDLIB_API size_t ZSTD_sizeof_CCtx(const ZSTD_CCtx* cctx);
+/*! ZSTD_initStaticCCtx() : initialize a fixed-size zstd compression context
+ *  workspace: The memory area to emplace the context into.
+ *             Provided pointer must 8-bytes aligned.
+ *             It must outlive context usage.
+ *  workspaceSize: Use ZSTD_estimateCCtxSize() or ZSTD_estimateCStreamSize()
+ *                 to determine how large workspace must be to support scenario.
+ * @return : pointer to ZSTD_CCtx*, or NULL if error (size too small)
+ *  Note : zstd will never resize nor malloc() when using a static cctx.
+ *         If it needs more memory than available, it will simply error out.
+ *  Note 2 : there is no corresponding "free" function.
+ *           Since workspace was allocated externally, it must be freed externally too.
+ *  Limitation 1 : currently not compatible with internal CDict creation, such as
+ *                 ZSTD_CCtx_loadDictionary() or ZSTD_initCStream_usingDict().
+ *  Limitation 2 : currently not compatible with multi-threading
+ */
+ZSTDLIB_API ZSTD_CCtx* ZSTD_initStaticCCtx(void* workspace, size_t workspaceSize);
+
 
+/* !!! To be deprecated !!! */
 typedef enum {
     ZSTD_p_forceWindow,   /* Force back-references to remain < windowSize, even when referencing Dictionary content (default:0) */
     ZSTD_p_forceRawDict   /* Force loading dictionary in "content-only" mode (no header analysis) */
@@ -479,20 +569,43 @@ typedef enum {
  *  @result : 0, or an error code (which can be tested with ZSTD_isError()) */
 ZSTDLIB_API size_t ZSTD_setCCtxParameter(ZSTD_CCtx* cctx, ZSTD_CCtxParameter param, unsigned value);
 
+
 /*! ZSTD_createCDict_byReference() :
  *  Create a digested dictionary for compression
  *  Dictionary content is simply referenced, and therefore stays in dictBuffer.
  *  It is important that dictBuffer outlives CDict, it must remain read accessible throughout the lifetime of CDict */
 ZSTDLIB_API ZSTD_CDict* ZSTD_createCDict_byReference(const void* dictBuffer, size_t dictSize, int compressionLevel);
 
+
+typedef enum { ZSTD_dm_auto=0,        /* dictionary is "full" if it starts with ZSTD_MAGIC_DICTIONARY, otherwise it is "rawContent" */
+               ZSTD_dm_rawContent,    /* ensures dictionary is always loaded as rawContent, even if it starts with ZSTD_MAGIC_DICTIONARY */
+               ZSTD_dm_fullDict       /* refuses to load a dictionary if it does not respect Zstandard's specification */
+} ZSTD_dictMode_e;
 /*! ZSTD_createCDict_advanced() :
  *  Create a ZSTD_CDict using external alloc and free, and customized compression parameters */
-ZSTDLIB_API ZSTD_CDict* ZSTD_createCDict_advanced(const void* dict, size_t dictSize, unsigned byReference,
-                                                  ZSTD_compressionParameters cParams, ZSTD_customMem customMem);
-
-/*! ZSTD_sizeof_CDict() :
- *  Gives the amount of memory used by a given ZSTD_sizeof_CDict */
-ZSTDLIB_API size_t ZSTD_sizeof_CDict(const ZSTD_CDict* cdict);
+ZSTDLIB_API ZSTD_CDict* ZSTD_createCDict_advanced(const void* dict, size_t dictSize,
+                                                  unsigned byReference, ZSTD_dictMode_e dictMode,
+                                                  ZSTD_compressionParameters cParams,
+                                                  ZSTD_customMem customMem);
+
+/*! ZSTD_initStaticCDict_advanced() :
+ *  Generate a digested dictionary in provided memory area.
+ *  workspace: The memory area to emplace the dictionary into.
+ *             Provided pointer must 8-bytes aligned.
+ *             It must outlive dictionary usage.
+ *  workspaceSize: Use ZSTD_estimateCDictSize()
+ *                 to determine how large workspace must be.
+ *  cParams : use ZSTD_getCParams() to transform a compression level
+ *            into its relevants cParams.
+ * @return : pointer to ZSTD_CDict*, or NULL if error (size too small)
+ *  Note : there is no corresponding "free" function.
+ *         Since workspace was allocated externally, it must be freed externally.
+ */
+ZSTDLIB_API ZSTD_CDict* ZSTD_initStaticCDict(
+                            void* workspace, size_t workspaceSize,
+                      const void* dict, size_t dictSize,
+                            unsigned byReference, ZSTD_dictMode_e dictMode,
+                            ZSTD_compressionParameters cParams);
 
 /*! ZSTD_getCParams() :
 *   @return ZSTD_compressionParameters structure for a selected compression level and estimated srcSize.
@@ -509,8 +622,8 @@ ZSTDLIB_API ZSTD_parameters ZSTD_getParams(int compressionLevel, unsigned long l
 ZSTDLIB_API size_t ZSTD_checkCParams(ZSTD_compressionParameters params);
 
 /*! ZSTD_adjustCParams() :
-*   optimize params for a given `srcSize` and `dictSize`.
-*   both values are optional, select `0` if unknown. */
+ *  optimize params for a given `srcSize` and `dictSize`.
+ *  both values are optional, select `0` if unknown. */
 ZSTDLIB_API ZSTD_compressionParameters ZSTD_adjustCParams(ZSTD_compressionParameters cPar, unsigned long long srcSize, size_t dictSize);
 
 /*! ZSTD_compress_advanced() :
@@ -538,22 +651,32 @@ ZSTDLIB_API size_t ZSTD_compress_usingCDict_advanced(ZSTD_CCtx* cctx,
  *  Note 3 : Skippable Frame Identifiers are considered valid. */
 ZSTDLIB_API unsigned ZSTD_isFrame(const void* buffer, size_t size);
 
-/*! ZSTD_estimateDCtxSize() :
- *  Gives the potential amount of memory allocated to create a ZSTD_DCtx */
-ZSTDLIB_API size_t ZSTD_estimateDCtxSize(void);
-
 /*! ZSTD_createDCtx_advanced() :
  *  Create a ZSTD decompression context using external alloc and free functions */
 ZSTDLIB_API ZSTD_DCtx* ZSTD_createDCtx_advanced(ZSTD_customMem customMem);
 
-/*! ZSTD_sizeof_DCtx() :
- *  Gives the amount of memory used by a given ZSTD_DCtx */
-ZSTDLIB_API size_t ZSTD_sizeof_DCtx(const ZSTD_DCtx* dctx);
+/*! ZSTD_initStaticDCtx() : initialize a fixed-size zstd decompression context
+ *  workspace: The memory area to emplace the context into.
+ *             Provided pointer must 8-bytes aligned.
+ *             It must outlive context usage.
+ *  workspaceSize: Use ZSTD_estimateDCtxSize() or ZSTD_estimateDStreamSize()
+ *                 to determine how large workspace must be to support scenario.
+ * @return : pointer to ZSTD_DCtx*, or NULL if error (size too small)
+ *  Note : zstd will never resize nor malloc() when using a static dctx.
+ *         If it needs more memory than available, it will simply error out.
+ *  Note 2 : static dctx is incompatible with legacy support
+ *  Note 3 : there is no corresponding "free" function.
+ *           Since workspace was allocated externally, it must be freed externally.
+ *  Limitation : currently not compatible with internal DDict creation,
+ *               such as ZSTD_initDStream_usingDict().
+ */
+ZSTDLIB_API ZSTD_DCtx* ZSTD_initStaticDCtx(void* workspace, size_t workspaceSize);
 
 /*! ZSTD_createDDict_byReference() :
  *  Create a digested dictionary, ready to start decompression operation without startup delay.
- *  Dictionary content is simply referenced, and therefore stays in dictBuffer.
- *  It is important that dictBuffer outlives DDict, it must remain read accessible throughout the lifetime of DDict */
+ *  Dictionary content is referenced, and therefore stays in dictBuffer.
+ *  It is important that dictBuffer outlives DDict,
+ *  it must remain read accessible throughout the lifetime of DDict */
 ZSTDLIB_API ZSTD_DDict* ZSTD_createDDict_byReference(const void* dictBuffer, size_t dictSize);
 
 /*! ZSTD_createDDict_advanced() :
@@ -561,9 +684,20 @@ ZSTDLIB_API ZSTD_DDict* ZSTD_createDDict_byReference(const void* dictBuffer, siz
 ZSTDLIB_API ZSTD_DDict* ZSTD_createDDict_advanced(const void* dict, size_t dictSize,
                                                   unsigned byReference, ZSTD_customMem customMem);
 
-/*! ZSTD_sizeof_DDict() :
- *  Gives the amount of memory used by a given ZSTD_DDict */
-ZSTDLIB_API size_t ZSTD_sizeof_DDict(const ZSTD_DDict* ddict);
+/*! ZSTD_initStaticDDict() :
+ *  Generate a digested dictionary in provided memory area.
+ *  workspace: The memory area to emplace the dictionary into.
+ *             Provided pointer must 8-bytes aligned.
+ *             It must outlive dictionary usage.
+ *  workspaceSize: Use ZSTD_estimateDDictSize()
+ *                 to determine how large workspace must be.
+ * @return : pointer to ZSTD_DDict*, or NULL if error (size too small)
+ *  Note : there is no corresponding "free" function.
+ *         Since workspace was allocated externally, it must be freed externally.
+ */
+ZSTDLIB_API ZSTD_DDict* ZSTD_initStaticDDict(void* workspace, size_t workspaceSize,
+                                             const void* dict, size_t dictSize,
+                                             unsigned byReference);
 
 /*! ZSTD_getDictID_fromDict() :
  *  Provides the dictID stored within dictionary.
@@ -586,7 +720,7 @@ ZSTDLIB_API unsigned ZSTD_getDictID_fromDDict(const ZSTD_DDict* ddict);
  *    Note : this use case also happens when using a non-conformant dictionary.
  *  - `srcSize` is too small, and as a result, the frame header could not be decoded (only possible if `srcSize < ZSTD_FRAMEHEADERSIZE_MAX`).
  *  - This is not a Zstandard frame.
- *  When identifying the exact failure cause, it's possible to use ZSTD_getFrameParams(), which will provide a more precise error code. */
+ *  When identifying the exact failure cause, it's possible to use ZSTD_getFrameHeader(), which will provide a more precise error code. */
 ZSTDLIB_API unsigned ZSTD_getDictID_fromFrame(const void* src, size_t srcSize);
 
 
@@ -596,13 +730,13 @@ ZSTDLIB_API unsigned ZSTD_getDictID_fromFrame(const void* src, size_t srcSize);
 
 /*=====   Advanced Streaming compression functions  =====*/
 ZSTDLIB_API ZSTD_CStream* ZSTD_createCStream_advanced(ZSTD_customMem customMem);
-ZSTDLIB_API size_t ZSTD_sizeof_CStream(const ZSTD_CStream* zcs);   /**< size of CStream is variable, depending primarily on compression level */
+ZSTDLIB_API ZSTD_CStream* ZSTD_initStaticCStream(void* workspace, size_t workspaceSize);    /**< same as ZSTD_initStaticCCtx() */
 ZSTDLIB_API size_t ZSTD_initCStream_srcSize(ZSTD_CStream* zcs, int compressionLevel, unsigned long long pledgedSrcSize);   /**< pledgedSrcSize must be correct, a size of 0 means unknown.  for a frame size of 0 use initCStream_advanced */
-ZSTDLIB_API size_t ZSTD_initCStream_usingDict(ZSTD_CStream* zcs, const void* dict, size_t dictSize, int compressionLevel); /**< note: a dict will not be used if dict == NULL or dictSize < 8 */
+ZSTDLIB_API size_t ZSTD_initCStream_usingDict(ZSTD_CStream* zcs, const void* dict, size_t dictSize, int compressionLevel); /**< creates of an internal CDict (incompatible with static CCtx), except if dict == NULL or dictSize < 8, in which case no dict is used. */
 ZSTDLIB_API size_t ZSTD_initCStream_advanced(ZSTD_CStream* zcs, const void* dict, size_t dictSize,
                                              ZSTD_parameters params, unsigned long long pledgedSrcSize);  /**< pledgedSrcSize is optional and can be 0 (meaning unknown). note: if the contentSizeFlag is set, pledgedSrcSize == 0 means the source size is actually 0 */
 ZSTDLIB_API size_t ZSTD_initCStream_usingCDict(ZSTD_CStream* zcs, const ZSTD_CDict* cdict);  /**< note : cdict will just be referenced, and must outlive compression session */
-ZSTDLIB_API size_t ZSTD_initCStream_usingCDict_advanced(ZSTD_CStream* zcs, const ZSTD_CDict* cdict, unsigned long long pledgedSrcSize, ZSTD_frameParameters fParams);  /**< same as ZSTD_initCStream_usingCDict(), with control over frame parameters */
+ZSTDLIB_API size_t ZSTD_initCStream_usingCDict_advanced(ZSTD_CStream* zcs, const ZSTD_CDict* cdict, ZSTD_frameParameters fParams, unsigned long long pledgedSrcSize);  /**< same as ZSTD_initCStream_usingCDict(), with control over frame parameters */
 
 /*! ZSTD_resetCStream() :
  *  start a new compression job, using same parameters from previous job.
@@ -617,11 +751,11 @@ ZSTDLIB_API size_t ZSTD_resetCStream(ZSTD_CStream* zcs, unsigned long long pledg
 /*=====   Advanced Streaming decompression functions  =====*/
 typedef enum { DStream_p_maxWindowSize } ZSTD_DStreamParameter_e;
 ZSTDLIB_API ZSTD_DStream* ZSTD_createDStream_advanced(ZSTD_customMem customMem);
-ZSTDLIB_API size_t ZSTD_initDStream_usingDict(ZSTD_DStream* zds, const void* dict, size_t dictSize); /**< note: a dict will not be used if dict == NULL or dictSize < 8 */
+ZSTDLIB_API ZSTD_DStream* ZSTD_initStaticDStream(void* workspace, size_t workspaceSize);    /**< same as ZSTD_initStaticDCtx() */
 ZSTDLIB_API size_t ZSTD_setDStreamParameter(ZSTD_DStream* zds, ZSTD_DStreamParameter_e paramType, unsigned paramValue);
+ZSTDLIB_API size_t ZSTD_initDStream_usingDict(ZSTD_DStream* zds, const void* dict, size_t dictSize); /**< note: a dict will not be used if dict == NULL or dictSize < 8 */
 ZSTDLIB_API size_t ZSTD_initDStream_usingDDict(ZSTD_DStream* zds, const ZSTD_DDict* ddict);  /**< note : ddict will just be referenced, and must outlive decompression session */
 ZSTDLIB_API size_t ZSTD_resetDStream(ZSTD_DStream* zds);  /**< re-use decompression parameters from previous init; saves dictionary loading */
-ZSTDLIB_API size_t ZSTD_sizeof_DStream(const ZSTD_DStream* zds);
 
 
 /*********************************************************************
@@ -683,21 +817,24 @@ ZSTDLIB_API size_t ZSTD_compressEnd(ZSTD_CCtx* cctx, void* dst, size_t dstCapaci
   Use ZSTD_createDCtx() / ZSTD_freeDCtx() to manage it.
   A ZSTD_DCtx object can be re-used multiple times.
 
-  First typical operation is to retrieve frame parameters, using ZSTD_getFrameParams().
-  It fills a ZSTD_frameParams structure which provide important information to correctly decode the frame,
-  such as the minimum rolling buffer size to allocate to decompress data (`windowSize`),
-  and the dictionary ID used.
+  First typical operation is to retrieve frame parameters, using ZSTD_getFrameHeader().
+  It fills a ZSTD_frameHeader structure with important information to correctly decode the frame,
+  such as minimum rolling buffer size to allocate to decompress data (`windowSize`),
+  and the dictionary ID in use.
   (Note : content size is optional, it may not be present. 0 means : content size unknown).
   Note that these values could be wrong, either because of data malformation, or because an attacker is spoofing deliberate false information.
   As a consequence, check that values remain within valid application range, especially `windowSize`, before allocation.
-  Each application can set its own limit, depending on local restrictions. For extended interoperability, it is recommended to support at least 8 MB.
-  Frame parameters are extracted from the beginning of the compressed frame.
-  Data fragment must be large enough to ensure successful decoding, typically `ZSTD_frameHeaderSize_max` bytes.
-  @result : 0 : successful decoding, the `ZSTD_frameParams` structure is correctly filled.
+  Each application can set its own limit, depending on local restrictions.
+  For extended interoperability, it is recommended to support windowSize of at least 8 MB.
+  Frame header is extracted from the beginning of compressed frame, so providing only the frame's beginning is enough.
+  Data fragment must be large enough to ensure successful decoding.
+  `ZSTD_frameHeaderSize_max` bytes is guaranteed to always be large enough.
+  @result : 0 : successful decoding, the `ZSTD_frameHeader` structure is correctly filled.
            >0 : `srcSize` is too small, please provide at least @result bytes on next attempt.
            errorCode, which can be tested using ZSTD_isError().
 
-  Start decompression, with ZSTD_decompressBegin() or ZSTD_decompressBegin_usingDict().
+  Start decompression, with ZSTD_decompressBegin().
+  If decompression requires a dictionary, use ZSTD_decompressBegin_usingDict() or ZSTD_decompressBegin_usingDDict().
   Alternatively, you can copy a prepared context, using ZSTD_copyDCtx().
 
   Then use ZSTD_nextSrcSizeToDecompress() and ZSTD_decompressContinue() alternatively.
@@ -729,30 +866,233 @@ ZSTDLIB_API size_t ZSTD_compressEnd(ZSTD_CCtx* cctx, void* dst, size_t dstCapaci
   b) Frame Size - 4 Bytes, Little endian format, unsigned 32-bits
   c) Frame Content - any content (User Data) of length equal to Frame Size
   For skippable frames ZSTD_decompressContinue() always returns 0.
-  For skippable frames ZSTD_getFrameParams() returns fparamsPtr->windowLog==0 what means that a frame is skippable.
+  For skippable frames ZSTD_getFrameHeader() returns fparamsPtr->windowLog==0 what means that a frame is skippable.
     Note : If fparamsPtr->frameContentSize==0, it is ambiguous: the frame might actually be a Zstd encoded frame with no content.
            For purposes of decompression, it is valid in both cases to skip the frame using
            ZSTD_findFrameCompressedSize to find its size in bytes.
   It also returns Frame Size as fparamsPtr->frameContentSize.
 */
 
-typedef struct {
-    unsigned long long frameContentSize;
-    unsigned windowSize;
-    unsigned dictID;
-    unsigned checksumFlag;
-} ZSTD_frameParams;
-
 /*=====   Buffer-less streaming decompression functions  =====*/
-ZSTDLIB_API size_t ZSTD_getFrameParams(ZSTD_frameParams* fparamsPtr, const void* src, size_t srcSize);   /**< doesn't consume input, see details below */
+ZSTDLIB_API size_t ZSTD_getFrameHeader(ZSTD_frameHeader* zfhPtr, const void* src, size_t srcSize);   /**< doesn't consume input */
 ZSTDLIB_API size_t ZSTD_decompressBegin(ZSTD_DCtx* dctx);
 ZSTDLIB_API size_t ZSTD_decompressBegin_usingDict(ZSTD_DCtx* dctx, const void* dict, size_t dictSize);
+ZSTDLIB_API size_t ZSTD_decompressBegin_usingDDict(ZSTD_DCtx* dctx, const ZSTD_DDict* ddict);
 ZSTDLIB_API void   ZSTD_copyDCtx(ZSTD_DCtx* dctx, const ZSTD_DCtx* preparedDCtx);
+
 ZSTDLIB_API size_t ZSTD_nextSrcSizeToDecompress(ZSTD_DCtx* dctx);
 ZSTDLIB_API size_t ZSTD_decompressContinue(ZSTD_DCtx* dctx, void* dst, size_t dstCapacity, const void* src, size_t srcSize);
 typedef enum { ZSTDnit_frameHeader, ZSTDnit_blockHeader, ZSTDnit_block, ZSTDnit_lastBlock, ZSTDnit_checksum, ZSTDnit_skippableFrame } ZSTD_nextInputType_e;
 ZSTDLIB_API ZSTD_nextInputType_e ZSTD_nextInputType(ZSTD_DCtx* dctx);
 
+
+
+/*===   New advanced API (experimental, and compression only)  ===*/
+
+/* notes on API design :
+ *   In this proposal, parameters are pushed one by one into an existing CCtx,
+ *   and then applied on all subsequent compression jobs.
+ *   When no parameter is ever provided, CCtx is created with compression level ZSTD_CLEVEL_DEFAULT.
+ *
+ *   This API is intended to replace all others experimental API.
+ *   It can basically do all other use cases, and even new ones.
+ *   It stands a good chance to become "stable",
+ *   after a reasonable testing period.
+ */
+
+/* note on naming convention :
+ *   Initially, the API favored names like ZSTD_setCCtxParameter() .
+ *   In this proposal, convention is changed towards ZSTD_CCtx_setParameter() .
+ *   The main driver is that it identifies more clearly the target object type.
+ *   It feels clearer in light of potential variants :
+ *   ZSTD_CDict_setParameter() (rather than ZSTD_setCDictParameter())
+ *   ZSTD_DCtx_setParameter()  (rather than ZSTD_setDCtxParameter() )
+ *   Left variant feels easier to distinguish.
+ */
+
+/* note on enum design :
+ * All enum will be manually set to explicit values before reaching "stable API" status */
+
+typedef enum {
+    /* compression parameters */
+    ZSTD_p_compressionLevel=100, /* Update all compression parameters according to pre-defined cLevel table
+                              * Default level is ZSTD_CLEVEL_DEFAULT==3.
+                              * Special: value 0 means "do not change cLevel". */
+    ZSTD_p_windowLog,        /* Maximum allowed back-reference distance, expressed as power of 2.
+                              * Must be clamped between ZSTD_WINDOWLOG_MIN and ZSTD_WINDOWLOG_MAX.
+                              * Special: value 0 means "do not change windowLog". */
+    ZSTD_p_hashLog,          /* Size of the probe table, as a power of 2.
+                              * Resulting table size is (1 << (hashLog+2)).
+                              * Must be clamped between ZSTD_HASHLOG_MIN and ZSTD_HASHLOG_MAX.
+                              * Larger tables improve compression ratio of strategies <= dFast,
+                              * and improve speed of strategies > dFast.
+                              * Special: value 0 means "do not change hashLog". */
+    ZSTD_p_chainLog,         /* Size of the full-search table, as a power of 2.
+                              * Resulting table size is (1 << (chainLog+2)).
+                              * Larger tables result in better and slower compression.
+                              * This parameter is useless when using "fast" strategy.
+                              * Special: value 0 means "do not change chainLog". */
+    ZSTD_p_searchLog,        /* Number of search attempts, as a power of 2.
+                              * More attempts result in better and slower compression.
+                              * This parameter is useless when using "fast" and "dFast" strategies.
+                              * Special: value 0 means "do not change searchLog". */
+    ZSTD_p_minMatch,         /* Minimum size of searched matches (note : repCode matches can be smaller).
+                              * Larger values make faster compression and decompression, but decrease ratio.
+                              * Must be clamped between ZSTD_SEARCHLENGTH_MIN and ZSTD_SEARCHLENGTH_MAX.
+                              * Note that currently, for all strategies < btopt, effective minimum is 4.
+                              * Note that currently, for all strategies > fast, effective maximum is 6.
+                              * Special: value 0 means "do not change minMatchLength". */
+    ZSTD_p_targetLength,     /* Only useful for strategies >= btopt.
+                              * Length of Match considered "good enough" to stop search.
+                              * Larger values make compression stronger and slower.
+                              * Special: value 0 means "do not change targetLength". */
+    ZSTD_p_compressionStrategy, /* See ZSTD_strategy enum definition.
+                              * Cast selected strategy as unsigned for ZSTD_CCtx_setParameter() compatibility.
+                              * The higher the value of selected strategy, the more complex it is,
+                              * resulting in stronger and slower compression.
+                              * Special: value 0 means "do not change strategy". */
+
+    /* frame parameters */
+    ZSTD_p_contentSizeFlag=200, /* Content size is written into frame header _whenever known_ (default:1) */
+    ZSTD_p_checksumFlag,     /* A 32-bits checksum of content is written at end of frame (default:0) */
+    ZSTD_p_dictIDFlag,       /* When applicable, dictID of dictionary is provided in frame header (default:1) */
+
+    /* dictionary parameters (must be set before ZSTD_CCtx_loadDictionary) */
+    ZSTD_p_dictMode=300,     /* Select how dictionary content must be interpreted. Value must be from type ZSTD_dictMode_e.
+                              * default : 0==auto : dictionary will be "full" if it respects specification, otherwise it will be "rawContent" */
+    ZSTD_p_refDictContent,   /* Dictionary content will be referenced, instead of copied (default:0==byCopy).
+                              * It requires that dictionary buffer outlives its users */
+
+    /* multi-threading parameters */
+    ZSTD_p_nbThreads=400,    /* Select how many threads a compression job can spawn (default:1)
+                              * More threads improve speed, but also increase memory usage.
+                              * Can only receive a value > 1 if ZSTD_MULTITHREAD is enabled.
+                              * Special: value 0 means "do not change nbThreads" */
+    ZSTD_p_jobSize,          /* Size of a compression job. Each compression job is completed in parallel.
+                              * 0 means default, which is dynamically determined based on compression parameters.
+                              * Job size must be a minimum of overlapSize, or 1 KB, whichever is largest
+                              * The minimum size is automatically and transparently enforced */
+    ZSTD_p_overlapSizeLog,   /* Size of previous input reloaded at the beginning of each job.
+                              * 0 => no overlap, 6(default) => use 1/8th of windowSize, >=9 => use full windowSize */
+
+    /* advanced parameters - may not remain available after API update */
+    ZSTD_p_forceMaxWindow=1100, /* Force back-reference distances to remain < windowSize,
+                              * even when referencing into Dictionary content (default:0) */
+
+} ZSTD_cParameter;
+
+
+/*! ZSTD_CCtx_setParameter() :
+ *  Set one compression parameter, selected by enum ZSTD_cParameter.
+ *  Note : when `value` is an enum, cast it to unsigned for proper type checking.
+ *  @result : 0, or an error code (which can be tested with ZSTD_isError()). */
+ZSTDLIB_API size_t ZSTD_CCtx_setParameter(ZSTD_CCtx* cctx, ZSTD_cParameter param, unsigned value);
+
+/*! ZSTD_CCtx_setPledgedSrcSize() :
+ *  Total input data size to be compressed as a single frame.
+ *  This value will be controlled at the end, and result in error if not respected.
+ * @result : 0, or an error code (which can be tested with ZSTD_isError()).
+ *  Note 1 : 0 means zero, empty.
+ *           In order to mean "unknown content size", pass constant ZSTD_CONTENTSIZE_UNKNOWN.
+ *           Note that ZSTD_CONTENTSIZE_UNKNOWN is default value for new compression jobs.
+ *  Note 2 : If all data is provided and consumed in a single round,
+ *           this value is overriden by srcSize instead. */
+ZSTDLIB_API size_t ZSTD_CCtx_setPledgedSrcSize(ZSTD_CCtx* cctx, unsigned long long pledgedSrcSize);
+
+/*! ZSTD_CCtx_loadDictionary() :
+ *  Create an internal CDict from dict buffer.
+ *  Decompression will have to use same buffer.
+ * @result : 0, or an error code (which can be tested with ZSTD_isError()).
+ *  Special : Adding a NULL (or 0-size) dictionary invalidates any previous dictionary,
+ *            meaning "return to no-dictionary mode".
+ *  Note 1 : `dict` content will be copied internally,
+ *           except if ZSTD_p_refDictContent is set before loading.
+ *  Note 2 : Loading a dictionary involves building tables, which are dependent on compression parameters.
+ *           For this reason, compression parameters cannot be changed anymore after loading a dictionary.
+ *           It's also a CPU-heavy operation, with non-negligible impact on latency.
+ *  Note 3 : Dictionary will be used for all future compression jobs.
+ *           To return to "no-dictionary" situation, load a NULL dictionary */
+ZSTDLIB_API size_t ZSTD_CCtx_loadDictionary(ZSTD_CCtx* cctx, const void* dict, size_t dictSize);
+
+/*! ZSTD_CCtx_refCDict() :
+ *  Reference a prepared dictionary, to be used for all next compression jobs.
+ *  Note that compression parameters are enforced from within CDict,
+ *  and supercede any compression parameter previously set within CCtx.
+ *  The dictionary will remain valid for future compression jobs using same CCtx.
+ * @result : 0, or an error code (which can be tested with ZSTD_isError()).
+ *  Special : adding a NULL CDict means "return to no-dictionary mode".
+ *  Note 1 : Currently, only one dictionary can be managed.
+ *           Adding a new dictionary effectively "discards" any previous one.
+ *  Note 2 : CDict is just referenced, its lifetime must outlive CCtx.
+ */
+ZSTDLIB_API size_t ZSTD_CCtx_refCDict(ZSTD_CCtx* cctx, const ZSTD_CDict* cdict);
+
+/*! ZSTD_CCtx_refPrefix() :
+ *  Reference a prefix (single-usage dictionary) for next compression job.
+ *  Decompression need same prefix to properly regenerate data.
+ *  Prefix is **only used once**. Tables are discarded at end of compression job.
+ *  Subsequent compression jobs will be done without prefix (if none is explicitly referenced).
+ *  If there is a need to use same prefix multiple times, consider embedding it into a ZSTD_CDict instead.
+ * @result : 0, or an error code (which can be tested with ZSTD_isError()).
+ *  Special : Adding any prefix (including NULL) invalidates any previous prefix or dictionary
+ *  Note 1 : Prefix buffer is referenced. It must outlive compression job.
+ *  Note 2 : Referencing a prefix involves building tables, which are dependent on compression parameters.
+ *           It's a CPU-heavy operation, with non-negligible impact on latency.
+ *  Note 3 : it's possible to alter ZSTD_p_dictMode using ZSTD_CCtx_setParameter() */
+ZSTDLIB_API size_t ZSTD_CCtx_refPrefix(ZSTD_CCtx* cctx, const void* prefix, size_t prefixSize);
+
+
+
+typedef enum {
+    ZSTD_e_continue=0, /* collect more data, encoder transparently decides when to output result, for optimal conditions */
+    ZSTD_e_flush,      /* flush any data provided so far - frame will continue, future data can still reference previous data for better compression */
+    ZSTD_e_end         /* flush any remaining data and ends current frame. Any future compression starts a new frame. */
+} ZSTD_EndDirective;
+
+/*! ZSTD_compress_generic() :
+ *  Behave about the same as ZSTD_compressStream. To note :
+ *  - Compression parameters are pushed into CCtx before starting compression, using ZSTD_CCtx_setParameter()
+ *  - Compression parameters cannot be changed once compression is started.
+ *  - *dstPos must be <= dstCapacity, *srcPos must be <= srcSize
+ *  - *dspPos and *srcPos will be updated. They are guaranteed to remain below their respective limit.
+ *  - @return provides the minimum amount of data still to flush from internal buffers
+ *            or an error code, which can be tested using ZSTD_isError().
+ *            if @return != 0, flush is not fully completed, there is some data left within internal buffers.
+ *  - after a ZSTD_e_end directive, if internal buffer is not fully flushed,
+ *            only ZSTD_e_end or ZSTD_e_flush operations are allowed.
+ *            It is necessary to fully flush internal buffers
+ *            before starting a new compression job, or changing compression parameters.
+ */
+ZSTDLIB_API size_t ZSTD_compress_generic (ZSTD_CCtx* cctx,
+                                          ZSTD_outBuffer* output,
+                                          ZSTD_inBuffer* input,
+                                          ZSTD_EndDirective endOp);
+
+/*! ZSTD_CCtx_reset() :
+ *  Return a CCtx to clean state.
+ *  Useful after an error, or to interrupt an ongoing compression job and start a new one.
+ *  Any internal data not yet flushed is cancelled.
+ *  Dictionary (if any) is dropped.
+ *  It's possible to modify compression parameters after a reset.
+ */
+ZSTDLIB_API void ZSTD_CCtx_reset(ZSTD_CCtx* cctx);   /* Not ready yet ! */
+
+
+/*! ZSTD_compress_generic_simpleArgs() :
+ *  Same as ZSTD_compress_generic(),
+ *  but using only integral types as arguments.
+ *  Argument list is larger and less expressive than ZSTD_{in,out}Buffer,
+ *  but can be helpful for binders from dynamic languages
+ *  which have troubles handling structures containing memory pointers.
+ */
+size_t ZSTD_compress_generic_simpleArgs (
+                            ZSTD_CCtx* cctx,
+                            void* dst, size_t dstCapacity, size_t* dstPos,
+                      const void* src, size_t srcSize, size_t* srcPos,
+                            ZSTD_EndDirective endOp);
+
+
+
 /**
     Block functions
 
@@ -767,7 +1107,7 @@ ZSTDLIB_API ZSTD_nextInputType_e ZSTD_nextInputType(ZSTD_DCtx* dctx);
       + compression : any ZSTD_compressBegin*() variant, including with dictionary
       + decompression : any ZSTD_decompressBegin*() variant, including with dictionary
       + copyCCtx() and copyDCtx() can be used too
-    - Block size is limited, it must be <= ZSTD_getBlockSizeMax() <= ZSTD_BLOCKSIZE_ABSOLUTEMAX
+    - Block size is limited, it must be <= ZSTD_getBlockSize() <= ZSTD_BLOCKSIZE_MAX
       + If input is larger than a block size, it's necessary to split input data into multiple blocks
       + For inputs larger than a single block size, consider using the regular ZSTD_compress() instead.
         Frame metadata is not that costly, and quickly becomes negligible as source size grows larger.
@@ -780,9 +1120,10 @@ ZSTDLIB_API ZSTD_nextInputType_e ZSTD_nextInputType(ZSTD_DCtx* dctx);
         Use ZSTD_insertBlock() for such a case.
 */
 
-#define ZSTD_BLOCKSIZE_ABSOLUTEMAX (128 * 1024)   /* define, for static allocation */
+#define ZSTD_BLOCKSIZELOG_MAX 17
+#define ZSTD_BLOCKSIZE_MAX   (1<<ZSTD_BLOCKSIZELOG_MAX)   /* define, for static allocation */
 /*=====   Raw zstd block functions  =====*/
-ZSTDLIB_API size_t ZSTD_getBlockSizeMax(ZSTD_CCtx* cctx);
+ZSTDLIB_API size_t ZSTD_getBlockSize   (const ZSTD_CCtx* cctx);
 ZSTDLIB_API size_t ZSTD_compressBlock  (ZSTD_CCtx* cctx, void* dst, size_t dstCapacity, const void* src, size_t srcSize);
 ZSTDLIB_API size_t ZSTD_decompressBlock(ZSTD_DCtx* dctx, void* dst, size_t dstCapacity, const void* src, size_t srcSize);
 ZSTDLIB_API size_t ZSTD_insertBlock(ZSTD_DCtx* dctx, const void* blockStart, size_t blockSize);  /**< insert block into `dctx` history. Useful for uncompressed blocks */