webp: Make it a module and unbundle libwebp thirdparty files

Note that there are two Godot-specific changes made to libwebp
for the javascript/HTML5 platform. They are documented in the
README.md.

1 files changed, 232 insertions, 0 deletions

diff --git a/thirdparty/libwebp/mux/muxi.h b/thirdparty/libwebp/mux/muxi.h
new file mode 100644
index 0000000000..d4d5cbad91
--- /dev/null
+++ b/thirdparty/libwebp/mux/muxi.h
@@ -0,0 +1,232 @@
+// Copyright 2011 Google Inc. All Rights Reserved.
+//
+// Use of this source code is governed by a BSD-style license
+// that can be found in the COPYING file in the root of the source
+// tree. An additional intellectual property rights grant can be found
+// in the file PATENTS. All contributing project authors may
+// be found in the AUTHORS file in the root of the source tree.
+// -----------------------------------------------------------------------------
+//
+// Internal header for mux library.
+//
+// Author: Urvang (urvang@google.com)
+
+#ifndef WEBP_MUX_MUXI_H_
+#define WEBP_MUX_MUXI_H_
+
+#include <stdlib.h>
+#include "../dec/vp8i.h"
+#include "../dec/vp8li.h"
+#include "../webp/mux.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+//------------------------------------------------------------------------------
+// Defines and constants.
+
+#define MUX_MAJ_VERSION 0
+#define MUX_MIN_VERSION 3
+#define MUX_REV_VERSION 1
+
+// Chunk object.
+typedef struct WebPChunk WebPChunk;
+struct WebPChunk {
+  uint32_t        tag_;
+  int             owner_;  // True if *data_ memory is owned internally.
+                           // VP8X, ANIM, and other internally created chunks
+                           // like ANMF/FRGM are always owned.
+  WebPData        data_;
+  WebPChunk*      next_;
+};
+
+// MuxImage object. Store a full WebP image (including ANMF/FRGM chunk, ALPH
+// chunk and VP8/VP8L chunk),
+typedef struct WebPMuxImage WebPMuxImage;
+struct WebPMuxImage {
+  WebPChunk*  header_;      // Corresponds to WEBP_CHUNK_ANMF/WEBP_CHUNK_FRGM.
+  WebPChunk*  alpha_;       // Corresponds to WEBP_CHUNK_ALPHA.
+  WebPChunk*  img_;         // Corresponds to WEBP_CHUNK_IMAGE.
+  WebPChunk*  unknown_;     // Corresponds to WEBP_CHUNK_UNKNOWN.
+  int         width_;
+  int         height_;
+  int         has_alpha_;   // Through ALPH chunk or as part of VP8L.
+  int         is_partial_;  // True if only some of the chunks are filled.
+  WebPMuxImage* next_;
+};
+
+// Main mux object. Stores data chunks.
+struct WebPMux {
+  WebPMuxImage*   images_;
+  WebPChunk*      iccp_;
+  WebPChunk*      exif_;
+  WebPChunk*      xmp_;
+  WebPChunk*      anim_;
+  WebPChunk*      vp8x_;
+
+  WebPChunk*      unknown_;
+  int             canvas_width_;
+  int             canvas_height_;
+};
+
+// CHUNK_INDEX enum: used for indexing within 'kChunks' (defined below) only.
+// Note: the reason for having two enums ('WebPChunkId' and 'CHUNK_INDEX') is to
+// allow two different chunks to have the same id (e.g. WebPChunkId
+// 'WEBP_CHUNK_IMAGE' can correspond to CHUNK_INDEX 'IDX_VP8' or 'IDX_VP8L').
+typedef enum {
+  IDX_VP8X = 0,
+  IDX_ICCP,
+  IDX_ANIM,
+  IDX_ANMF,
+  IDX_FRGM,
+  IDX_ALPHA,
+  IDX_VP8,
+  IDX_VP8L,
+  IDX_EXIF,
+  IDX_XMP,
+  IDX_UNKNOWN,
+
+  IDX_NIL,
+  IDX_LAST_CHUNK
+} CHUNK_INDEX;
+
+#define NIL_TAG 0x00000000u  // To signal void chunk.
+
+typedef struct {
+  uint32_t      tag;
+  WebPChunkId   id;
+  uint32_t      size;
+} ChunkInfo;
+
+extern const ChunkInfo kChunks[IDX_LAST_CHUNK];
+
+//------------------------------------------------------------------------------
+// Chunk object management.
+
+// Initialize.
+void ChunkInit(WebPChunk* const chunk);
+
+// Get chunk index from chunk tag. Returns IDX_UNKNOWN if not found.
+CHUNK_INDEX ChunkGetIndexFromTag(uint32_t tag);
+
+// Get chunk id from chunk tag. Returns WEBP_CHUNK_UNKNOWN if not found.
+WebPChunkId ChunkGetIdFromTag(uint32_t tag);
+
+// Convert a fourcc string to a tag.
+uint32_t ChunkGetTagFromFourCC(const char fourcc[4]);
+
+// Get chunk index from fourcc. Returns IDX_UNKNOWN if given fourcc is unknown.
+CHUNK_INDEX ChunkGetIndexFromFourCC(const char fourcc[4]);
+
+// Search for nth chunk with given 'tag' in the chunk list.
+// nth = 0 means "last of the list".
+WebPChunk* ChunkSearchList(WebPChunk* first, uint32_t nth, uint32_t tag);
+
+// Fill the chunk with the given data.
+WebPMuxError ChunkAssignData(WebPChunk* chunk, const WebPData* const data,
+                             int copy_data, uint32_t tag);
+
+// Sets 'chunk' at nth position in the 'chunk_list'.
+// nth = 0 has the special meaning "last of the list".
+// On success ownership is transferred from 'chunk' to the 'chunk_list'.
+WebPMuxError ChunkSetNth(WebPChunk* chunk, WebPChunk** chunk_list,
+                         uint32_t nth);
+
+// Releases chunk and returns chunk->next_.
+WebPChunk* ChunkRelease(WebPChunk* const chunk);
+
+// Deletes given chunk & returns chunk->next_.
+WebPChunk* ChunkDelete(WebPChunk* const chunk);
+
+// Deletes all chunks in the given chunk list.
+void ChunkListDelete(WebPChunk** const chunk_list);
+
+// Returns size of the chunk including chunk header and padding byte (if any).
+static WEBP_INLINE size_t SizeWithPadding(size_t chunk_size) {
+  return CHUNK_HEADER_SIZE + ((chunk_size + 1) & ~1U);
+}
+
+// Size of a chunk including header and padding.
+static WEBP_INLINE size_t ChunkDiskSize(const WebPChunk* chunk) {
+  const size_t data_size = chunk->data_.size;
+  assert(data_size < MAX_CHUNK_PAYLOAD);
+  return SizeWithPadding(data_size);
+}
+
+// Total size of a list of chunks.
+size_t ChunkListDiskSize(const WebPChunk* chunk_list);
+
+// Write out the given list of chunks into 'dst'.
+uint8_t* ChunkListEmit(const WebPChunk* chunk_list, uint8_t* dst);
+
+//------------------------------------------------------------------------------
+// MuxImage object management.
+
+// Initialize.
+void MuxImageInit(WebPMuxImage* const wpi);
+
+// Releases image 'wpi' and returns wpi->next.
+WebPMuxImage* MuxImageRelease(WebPMuxImage* const wpi);
+
+// Delete image 'wpi' and return the next image in the list or NULL.
+// 'wpi' can be NULL.
+WebPMuxImage* MuxImageDelete(WebPMuxImage* const wpi);
+
+// Count number of images matching the given tag id in the 'wpi_list'.
+// If id == WEBP_CHUNK_NIL, all images will be matched.
+int MuxImageCount(const WebPMuxImage* wpi_list, WebPChunkId id);
+
+// Update width/height/has_alpha info from chunks within wpi.
+// Also remove ALPH chunk if not needed.
+int MuxImageFinalize(WebPMuxImage* const wpi);
+
+// Check if given ID corresponds to an image related chunk.
+static WEBP_INLINE int IsWPI(WebPChunkId id) {
+  switch (id) {
+    case WEBP_CHUNK_ANMF:
+    case WEBP_CHUNK_FRGM:
+    case WEBP_CHUNK_ALPHA:
+    case WEBP_CHUNK_IMAGE:  return 1;
+    default:        return 0;
+  }
+}
+
+// Pushes 'wpi' at the end of 'wpi_list'.
+WebPMuxError MuxImagePush(const WebPMuxImage* wpi, WebPMuxImage** wpi_list);
+
+// Delete nth image in the image list.
+WebPMuxError MuxImageDeleteNth(WebPMuxImage** wpi_list, uint32_t nth);
+
+// Get nth image in the image list.
+WebPMuxError MuxImageGetNth(const WebPMuxImage** wpi_list, uint32_t nth,
+                            WebPMuxImage** wpi);
+
+// Total size of the given image.
+size_t MuxImageDiskSize(const WebPMuxImage* const wpi);
+
+// Write out the given image into 'dst'.
+uint8_t* MuxImageEmit(const WebPMuxImage* const wpi, uint8_t* dst);
+
+//------------------------------------------------------------------------------
+// Helper methods for mux.
+
+// Checks if the given image list contains at least one image with alpha.
+int MuxHasAlpha(const WebPMuxImage* images);
+
+// Write out RIFF header into 'data', given total data size 'size'.
+uint8_t* MuxEmitRiffHeader(uint8_t* const data, size_t size);
+
+// Returns the list where chunk with given ID is to be inserted in mux.
+WebPChunk** MuxGetChunkListFromId(const WebPMux* mux, WebPChunkId id);
+
+// Validates the given mux object.
+WebPMuxError MuxValidate(const WebPMux* const mux);
+
+//------------------------------------------------------------------------------
+
+#ifdef __cplusplus
+}    // extern "C"
+#endif
+
+#endif  /* WEBP_MUX_MUXI_H_ */