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Diffstat (limited to 'thirdparty/zstd/compress/zstd_compress_internal.h')
-rw-r--r--thirdparty/zstd/compress/zstd_compress_internal.h150
1 files changed, 136 insertions, 14 deletions
diff --git a/thirdparty/zstd/compress/zstd_compress_internal.h b/thirdparty/zstd/compress/zstd_compress_internal.h
index 14036f873f..db73f6ce21 100644
--- a/thirdparty/zstd/compress/zstd_compress_internal.h
+++ b/thirdparty/zstd/compress/zstd_compress_internal.h
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 2016-present, Yann Collet, Facebook, Inc.
+ * Copyright (c) 2016-2020, Yann Collet, Facebook, Inc.
* All rights reserved.
*
* This source code is licensed under both the BSD-style license (found in the
@@ -18,7 +18,7 @@
/*-*************************************
* Dependencies
***************************************/
-#include "zstd_internal.h"
+#include "../common/zstd_internal.h"
#include "zstd_cwksp.h"
#ifdef ZSTD_MULTITHREAD
# include "zstdmt_compress.h"
@@ -166,6 +166,7 @@ typedef struct {
typedef struct {
ZSTD_window_t window; /* State for the window round buffer management */
ldmEntry_t* hashTable;
+ U32 loadedDictEnd;
BYTE* bucketOffsets; /* Next position in bucket to insert entry */
U64 hashPower; /* Used to compute the rolling hash.
* Depends on ldmParams.minMatchLength */
@@ -249,6 +250,7 @@ struct ZSTD_CCtx_s {
size_t staticSize;
SeqCollector seqCollector;
int isFirstBlock;
+ int initialized;
seqStore_t seqStore; /* sequences storage ptrs */
ldmState_t ldmState; /* long distance matching state */
@@ -324,6 +326,31 @@ MEM_STATIC U32 ZSTD_MLcode(U32 mlBase)
return (mlBase > 127) ? ZSTD_highbit32(mlBase) + ML_deltaCode : ML_Code[mlBase];
}
+typedef struct repcodes_s {
+ U32 rep[3];
+} repcodes_t;
+
+MEM_STATIC repcodes_t ZSTD_updateRep(U32 const rep[3], U32 const offset, U32 const ll0)
+{
+ repcodes_t newReps;
+ if (offset >= ZSTD_REP_NUM) { /* full offset */
+ newReps.rep[2] = rep[1];
+ newReps.rep[1] = rep[0];
+ newReps.rep[0] = offset - ZSTD_REP_MOVE;
+ } else { /* repcode */
+ U32 const repCode = offset + ll0;
+ if (repCode > 0) { /* note : if repCode==0, no change */
+ U32 const currentOffset = (repCode==ZSTD_REP_NUM) ? (rep[0] - 1) : rep[repCode];
+ newReps.rep[2] = (repCode >= 2) ? rep[1] : rep[2];
+ newReps.rep[1] = rep[0];
+ newReps.rep[0] = currentOffset;
+ } else { /* repCode == 0 */
+ memcpy(&newReps, rep, sizeof(newReps));
+ }
+ }
+ return newReps;
+}
+
/* ZSTD_cParam_withinBounds:
* @return 1 if value is within cParam bounds,
* 0 otherwise */
@@ -336,6 +363,30 @@ MEM_STATIC int ZSTD_cParam_withinBounds(ZSTD_cParameter cParam, int value)
return 1;
}
+/* ZSTD_noCompressBlock() :
+ * Writes uncompressed block to dst buffer from given src.
+ * Returns the size of the block */
+MEM_STATIC size_t ZSTD_noCompressBlock (void* dst, size_t dstCapacity, const void* src, size_t srcSize, U32 lastBlock)
+{
+ U32 const cBlockHeader24 = lastBlock + (((U32)bt_raw)<<1) + (U32)(srcSize << 3);
+ RETURN_ERROR_IF(srcSize + ZSTD_blockHeaderSize > dstCapacity,
+ dstSize_tooSmall, "dst buf too small for uncompressed block");
+ MEM_writeLE24(dst, cBlockHeader24);
+ memcpy((BYTE*)dst + ZSTD_blockHeaderSize, src, srcSize);
+ return ZSTD_blockHeaderSize + srcSize;
+}
+
+MEM_STATIC size_t ZSTD_rleCompressBlock (void* dst, size_t dstCapacity, BYTE src, size_t srcSize, U32 lastBlock)
+{
+ BYTE* const op = (BYTE*)dst;
+ U32 const cBlockHeader = lastBlock + (((U32)bt_rle)<<1) + (U32)(srcSize << 3);
+ RETURN_ERROR_IF(dstCapacity < 4, dstSize_tooSmall, "");
+ MEM_writeLE24(op, cBlockHeader);
+ op[3] = src;
+ return 4;
+}
+
+
/* ZSTD_minGain() :
* minimum compression required
* to generate a compress block or a compressed literals section.
@@ -348,6 +399,21 @@ MEM_STATIC size_t ZSTD_minGain(size_t srcSize, ZSTD_strategy strat)
return (srcSize >> minlog) + 2;
}
+MEM_STATIC int ZSTD_disableLiteralsCompression(const ZSTD_CCtx_params* cctxParams)
+{
+ switch (cctxParams->literalCompressionMode) {
+ case ZSTD_lcm_huffman:
+ return 0;
+ case ZSTD_lcm_uncompressed:
+ return 1;
+ default:
+ assert(0 /* impossible: pre-validated */);
+ /* fall-through */
+ case ZSTD_lcm_auto:
+ return (cctxParams->cParams.strategy == ZSTD_fast) && (cctxParams->cParams.targetLength > 0);
+ }
+}
+
/*! ZSTD_safecopyLiterals() :
* memcpy() function that won't read beyond more than WILDCOPY_OVERLENGTH bytes past ilimit_w.
* Only called when the sequence ends past ilimit_w, so it only needs to be optimized for single
@@ -433,8 +499,7 @@ static unsigned ZSTD_NbCommonBytes (size_t val)
if (MEM_64bits()) {
# if defined(_MSC_VER) && defined(_WIN64)
unsigned long r = 0;
- _BitScanForward64( &r, (U64)val );
- return (unsigned)(r>>3);
+ return _BitScanForward64( &r, (U64)val ) ? (unsigned)(r >> 3) : 0;
# elif defined(__GNUC__) && (__GNUC__ >= 4)
return (__builtin_ctzll((U64)val) >> 3);
# else
@@ -451,8 +516,7 @@ static unsigned ZSTD_NbCommonBytes (size_t val)
} else { /* 32 bits */
# if defined(_MSC_VER)
unsigned long r=0;
- _BitScanForward( &r, (U32)val );
- return (unsigned)(r>>3);
+ return _BitScanForward( &r, (U32)val ) ? (unsigned)(r >> 3) : 0;
# elif defined(__GNUC__) && (__GNUC__ >= 3)
return (__builtin_ctz((U32)val) >> 3);
# else
@@ -467,8 +531,7 @@ static unsigned ZSTD_NbCommonBytes (size_t val)
if (MEM_64bits()) {
# if defined(_MSC_VER) && defined(_WIN64)
unsigned long r = 0;
- _BitScanReverse64( &r, val );
- return (unsigned)(r>>3);
+ return _BitScanReverse64( &r, val ) ? (unsigned)(r >> 3) : 0;
# elif defined(__GNUC__) && (__GNUC__ >= 4)
return (__builtin_clzll(val) >> 3);
# else
@@ -482,8 +545,7 @@ static unsigned ZSTD_NbCommonBytes (size_t val)
} else { /* 32 bits */
# if defined(_MSC_VER)
unsigned long r = 0;
- _BitScanReverse( &r, (unsigned long)val );
- return (unsigned)(r>>3);
+ return _BitScanReverse( &r, (unsigned long)val ) ? (unsigned)(r >> 3) : 0;
# elif defined(__GNUC__) && (__GNUC__ >= 3)
return (__builtin_clz((U32)val) >> 3);
# else
@@ -730,7 +792,10 @@ MEM_STATIC U32 ZSTD_window_correctOverflow(ZSTD_window_t* window, U32 cycleLog,
*/
U32 const cycleMask = (1U << cycleLog) - 1;
U32 const current = (U32)((BYTE const*)src - window->base);
- U32 const newCurrent = (current & cycleMask) + maxDist;
+ U32 const currentCycle0 = current & cycleMask;
+ /* Exclude zero so that newCurrent - maxDist >= 1. */
+ U32 const currentCycle1 = currentCycle0 == 0 ? (1U << cycleLog) : currentCycle0;
+ U32 const newCurrent = currentCycle1 + maxDist;
U32 const correction = current - newCurrent;
assert((maxDist & cycleMask) == 0);
assert(current > newCurrent);
@@ -739,8 +804,17 @@ MEM_STATIC U32 ZSTD_window_correctOverflow(ZSTD_window_t* window, U32 cycleLog,
window->base += correction;
window->dictBase += correction;
- window->lowLimit -= correction;
- window->dictLimit -= correction;
+ if (window->lowLimit <= correction) window->lowLimit = 1;
+ else window->lowLimit -= correction;
+ if (window->dictLimit <= correction) window->dictLimit = 1;
+ else window->dictLimit -= correction;
+
+ /* Ensure we can still reference the full window. */
+ assert(newCurrent >= maxDist);
+ assert(newCurrent - maxDist >= 1);
+ /* Ensure that lowLimit and dictLimit didn't underflow. */
+ assert(window->lowLimit <= newCurrent);
+ assert(window->dictLimit <= newCurrent);
DEBUGLOG(4, "Correction of 0x%x bytes to lowLimit=0x%x", correction,
window->lowLimit);
@@ -844,6 +918,15 @@ ZSTD_checkDictValidity(const ZSTD_window_t* window,
} } }
}
+MEM_STATIC void ZSTD_window_init(ZSTD_window_t* window) {
+ memset(window, 0, sizeof(*window));
+ window->base = (BYTE const*)"";
+ window->dictBase = (BYTE const*)"";
+ window->dictLimit = 1; /* start from 1, so that 1st position is valid */
+ window->lowLimit = 1; /* it ensures first and later CCtx usages compress the same */
+ window->nextSrc = window->base + 1; /* see issue #1241 */
+}
+
/**
* ZSTD_window_update():
* Updates the window by appending [src, src + srcSize) to the window.
@@ -857,6 +940,10 @@ MEM_STATIC U32 ZSTD_window_update(ZSTD_window_t* window,
BYTE const* const ip = (BYTE const*)src;
U32 contiguous = 1;
DEBUGLOG(5, "ZSTD_window_update");
+ if (srcSize == 0)
+ return contiguous;
+ assert(window->base != NULL);
+ assert(window->dictBase != NULL);
/* Check if blocks follow each other */
if (src != window->nextSrc) {
/* not contiguous */
@@ -867,7 +954,7 @@ MEM_STATIC U32 ZSTD_window_update(ZSTD_window_t* window,
window->dictLimit = (U32)distanceFromBase;
window->dictBase = window->base;
window->base = ip - distanceFromBase;
- // ms->nextToUpdate = window->dictLimit;
+ /* ms->nextToUpdate = window->dictLimit; */
if (window->dictLimit - window->lowLimit < HASH_READ_SIZE) window->lowLimit = window->dictLimit; /* too small extDict */
contiguous = 0;
}
@@ -883,6 +970,9 @@ MEM_STATIC U32 ZSTD_window_update(ZSTD_window_t* window,
return contiguous;
}
+/**
+ * Returns the lowest allowed match index. It may either be in the ext-dict or the prefix.
+ */
MEM_STATIC U32 ZSTD_getLowestMatchIndex(const ZSTD_matchState_t* ms, U32 current, unsigned windowLog)
{
U32 const maxDistance = 1U << windowLog;
@@ -893,6 +983,19 @@ MEM_STATIC U32 ZSTD_getLowestMatchIndex(const ZSTD_matchState_t* ms, U32 current
return matchLowest;
}
+/**
+ * Returns the lowest allowed match index in the prefix.
+ */
+MEM_STATIC U32 ZSTD_getLowestPrefixIndex(const ZSTD_matchState_t* ms, U32 current, unsigned windowLog)
+{
+ U32 const maxDistance = 1U << windowLog;
+ U32 const lowestValid = ms->window.dictLimit;
+ U32 const withinWindow = (current - lowestValid > maxDistance) ? current - maxDistance : lowestValid;
+ U32 const isDictionary = (ms->loadedDictEnd != 0);
+ U32 const matchLowest = isDictionary ? lowestValid : withinWindow;
+ return matchLowest;
+}
+
/* debug functions */
@@ -931,6 +1034,21 @@ MEM_STATIC void ZSTD_debugTable(const U32* table, U32 max)
}
#endif
+/* ===============================================================
+ * Shared internal declarations
+ * These prototypes may be called from sources not in lib/compress
+ * =============================================================== */
+
+/* ZSTD_loadCEntropy() :
+ * dict : must point at beginning of a valid zstd dictionary.
+ * return : size of dictionary header (size of magic number + dict ID + entropy tables)
+ * assumptions : magic number supposed already checked
+ * and dictSize >= 8 */
+size_t ZSTD_loadCEntropy(ZSTD_compressedBlockState_t* bs, void* workspace,
+ short* offcodeNCount, unsigned* offcodeMaxValue,
+ const void* const dict, size_t dictSize);
+
+void ZSTD_reset_compressedBlockState(ZSTD_compressedBlockState_t* bs);
/* ==============================================================
* Private declarations
@@ -940,6 +1058,7 @@ MEM_STATIC void ZSTD_debugTable(const U32* table, U32 max)
/* ZSTD_getCParamsFromCCtxParams() :
* cParams are built depending on compressionLevel, src size hints,
* LDM and manually set compression parameters.
+ * Note: srcSizeHint == 0 means 0!
*/
ZSTD_compressionParameters ZSTD_getCParamsFromCCtxParams(
const ZSTD_CCtx_params* CCtxParams, U64 srcSizeHint, size_t dictSize);
@@ -999,5 +1118,8 @@ size_t ZSTD_writeLastEmptyBlock(void* dst, size_t dstCapacity);
*/
size_t ZSTD_referenceExternalSequences(ZSTD_CCtx* cctx, rawSeq* seq, size_t nbSeq);
+/** ZSTD_cycleLog() :
+ * condition for correct operation : hashLog > 1 */
+U32 ZSTD_cycleLog(U32 hashLog, ZSTD_strategy strat);
#endif /* ZSTD_COMPRESS_H */
generated by cgit v1.2.3 (git 2.25.1) at 2025-02-26 08:16:55 +0000