// 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 objects and utils for mux. // // Authors: Urvang (urvang@google.com) // Vikas (vikasa@google.com) #include <assert.h> #include "src/mux/muxi.h" #include "src/utils/utils.h" #define UNDEFINED_CHUNK_SIZE ((uint32_t)(-1)) const ChunkInfo kChunks[] = { { MKFOURCC('V', 'P', '8', 'X'), WEBP_CHUNK_VP8X, VP8X_CHUNK_SIZE }, { MKFOURCC('I', 'C', 'C', 'P'), WEBP_CHUNK_ICCP, UNDEFINED_CHUNK_SIZE }, { MKFOURCC('A', 'N', 'I', 'M'), WEBP_CHUNK_ANIM, ANIM_CHUNK_SIZE }, { MKFOURCC('A', 'N', 'M', 'F'), WEBP_CHUNK_ANMF, ANMF_CHUNK_SIZE }, { MKFOURCC('A', 'L', 'P', 'H'), WEBP_CHUNK_ALPHA, UNDEFINED_CHUNK_SIZE }, { MKFOURCC('V', 'P', '8', ' '), WEBP_CHUNK_IMAGE, UNDEFINED_CHUNK_SIZE }, { MKFOURCC('V', 'P', '8', 'L'), WEBP_CHUNK_IMAGE, UNDEFINED_CHUNK_SIZE }, { MKFOURCC('E', 'X', 'I', 'F'), WEBP_CHUNK_EXIF, UNDEFINED_CHUNK_SIZE }, { MKFOURCC('X', 'M', 'P', ' '), WEBP_CHUNK_XMP, UNDEFINED_CHUNK_SIZE }, { NIL_TAG, WEBP_CHUNK_UNKNOWN, UNDEFINED_CHUNK_SIZE }, { NIL_TAG, WEBP_CHUNK_NIL, UNDEFINED_CHUNK_SIZE } }; //------------------------------------------------------------------------------ int WebPGetMuxVersion(void) { return (MUX_MAJ_VERSION << 16) | (MUX_MIN_VERSION << 8) | MUX_REV_VERSION; } //------------------------------------------------------------------------------ // Life of a chunk object. void ChunkInit(WebPChunk* const chunk) { assert(chunk); memset(chunk, 0, sizeof(*chunk)); chunk->tag_ = NIL_TAG; } WebPChunk* ChunkRelease(WebPChunk* const chunk) { WebPChunk* next; if (chunk == NULL) return NULL; if (chunk->owner_) { WebPDataClear(&chunk->data_); } next = chunk->next_; ChunkInit(chunk); return next; } //------------------------------------------------------------------------------ // Chunk misc methods. CHUNK_INDEX ChunkGetIndexFromTag(uint32_t tag) { int i; for (i = 0; kChunks[i].tag != NIL_TAG; ++i) { if (tag == kChunks[i].tag) return (CHUNK_INDEX)i; } return IDX_UNKNOWN; } WebPChunkId ChunkGetIdFromTag(uint32_t tag) { int i; for (i = 0; kChunks[i].tag != NIL_TAG; ++i) { if (tag == kChunks[i].tag) return kChunks[i].id; } return WEBP_CHUNK_UNKNOWN; } uint32_t ChunkGetTagFromFourCC(const char fourcc[4]) { return MKFOURCC(fourcc[0], fourcc[1], fourcc[2], fourcc[3]); } CHUNK_INDEX ChunkGetIndexFromFourCC(const char fourcc[4]) { const uint32_t tag = ChunkGetTagFromFourCC(fourcc); return ChunkGetIndexFromTag(tag); } //------------------------------------------------------------------------------ // Chunk search methods. // Returns next chunk in the chunk list with the given tag. static WebPChunk* ChunkSearchNextInList(WebPChunk* chunk, uint32_t tag) { while (chunk != NULL && chunk->tag_ != tag) { chunk = chunk->next_; } return chunk; } WebPChunk* ChunkSearchList(WebPChunk* first, uint32_t nth, uint32_t tag) { uint32_t iter = nth; first = ChunkSearchNextInList(first, tag); if (first == NULL) return NULL; while (--iter != 0) { WebPChunk* next_chunk = ChunkSearchNextInList(first->next_, tag); if (next_chunk == NULL) break; first = next_chunk; } return ((nth > 0) && (iter > 0)) ? NULL : first; } // Outputs a pointer to 'prev_chunk->next_', // where 'prev_chunk' is the pointer to the chunk at position (nth - 1). // Returns true if nth chunk was found. static int ChunkSearchListToSet(WebPChunk** chunk_list, uint32_t nth, WebPChunk*** const location) { uint32_t count = 0; assert(chunk_list != NULL); *location = chunk_list; while (*chunk_list != NULL) { WebPChunk* const cur_chunk = *chunk_list; ++count; if (count == nth) return 1; // Found. chunk_list = &cur_chunk->next_; *location = chunk_list; } // *chunk_list is ok to be NULL if adding at last location. return (nth == 0 || (count == nth - 1)) ? 1 : 0; } //------------------------------------------------------------------------------ // Chunk writer methods. WebPMuxError ChunkAssignData(WebPChunk* chunk, const WebPData* const data, int copy_data, uint32_t tag) { // For internally allocated chunks, always copy data & make it owner of data. if (tag == kChunks[IDX_VP8X].tag || tag == kChunks[IDX_ANIM].tag) { copy_data = 1; } ChunkRelease(chunk); if (data != NULL) { if (copy_data) { // Copy data. if (!WebPDataCopy(data, &chunk->data_)) return WEBP_MUX_MEMORY_ERROR; chunk->owner_ = 1; // Chunk is owner of data. } else { // Don't copy data. chunk->data_ = *data; } } chunk->tag_ = tag; return WEBP_MUX_OK; } WebPMuxError ChunkSetNth(WebPChunk* chunk, WebPChunk** chunk_list, uint32_t nth) { WebPChunk* new_chunk; if (!ChunkSearchListToSet(chunk_list, nth, &chunk_list)) { return WEBP_MUX_NOT_FOUND; } new_chunk = (WebPChunk*)WebPSafeMalloc(1ULL, sizeof(*new_chunk)); if (new_chunk == NULL) return WEBP_MUX_MEMORY_ERROR; *new_chunk = *chunk; chunk->owner_ = 0; new_chunk->next_ = *chunk_list; *chunk_list = new_chunk; return WEBP_MUX_OK; } //------------------------------------------------------------------------------ // Chunk deletion method(s). WebPChunk* ChunkDelete(WebPChunk* const chunk) { WebPChunk* const next = ChunkRelease(chunk); WebPSafeFree(chunk); return next; } void ChunkListDelete(WebPChunk** const chunk_list) { while (*chunk_list != NULL) { *chunk_list = ChunkDelete(*chunk_list); } } //------------------------------------------------------------------------------ // Chunk serialization methods. static uint8_t* ChunkEmit(const WebPChunk* const chunk, uint8_t* dst) { const size_t chunk_size = chunk->data_.size; assert(chunk); assert(chunk->tag_ != NIL_TAG); PutLE32(dst + 0, chunk->tag_); PutLE32(dst + TAG_SIZE, (uint32_t)chunk_size); assert(chunk_size == (uint32_t)chunk_size); memcpy(dst + CHUNK_HEADER_SIZE, chunk->data_.bytes, chunk_size); if (chunk_size & 1) dst[CHUNK_HEADER_SIZE + chunk_size] = 0; // Add padding. return dst + ChunkDiskSize(chunk); } uint8_t* ChunkListEmit(const WebPChunk* chunk_list, uint8_t* dst) { while (chunk_list != NULL) { dst = ChunkEmit(chunk_list, dst); chunk_list = chunk_list->next_; } return dst; } size_t ChunkListDiskSize(const WebPChunk* chunk_list) { size_t size = 0; while (chunk_list != NULL) { size += ChunkDiskSize(chunk_list); chunk_list = chunk_list->next_; } return size; } //------------------------------------------------------------------------------ // Life of a MuxImage object. void MuxImageInit(WebPMuxImage* const wpi) { assert(wpi); memset(wpi, 0, sizeof(*wpi)); } WebPMuxImage* MuxImageRelease(WebPMuxImage* const wpi) { WebPMuxImage* next; if (wpi == NULL) return NULL; ChunkDelete(wpi->header_); ChunkDelete(wpi->alpha_); ChunkDelete(wpi->img_); ChunkListDelete(&wpi->unknown_); next = wpi->next_; MuxImageInit(wpi); return next; } //------------------------------------------------------------------------------ // MuxImage search methods. // Get a reference to appropriate chunk list within an image given chunk tag. static WebPChunk** GetChunkListFromId(const WebPMuxImage* const wpi, WebPChunkId id) { assert(wpi != NULL); switch (id) { case WEBP_CHUNK_ANMF: return (WebPChunk**)&wpi->header_; case WEBP_CHUNK_ALPHA: return (WebPChunk**)&wpi->alpha_; case WEBP_CHUNK_IMAGE: return (WebPChunk**)&wpi->img_; default: return NULL; } } int MuxImageCount(const WebPMuxImage* wpi_list, WebPChunkId id) { int count = 0; const WebPMuxImage* current; for (current = wpi_list; current != NULL; current = current->next_) { if (id == WEBP_CHUNK_NIL) { ++count; // Special case: count all images. } else { const WebPChunk* const wpi_chunk = *GetChunkListFromId(current, id); if (wpi_chunk != NULL) { const WebPChunkId wpi_chunk_id = ChunkGetIdFromTag(wpi_chunk->tag_); if (wpi_chunk_id == id) ++count; // Count images with a matching 'id'. } } } return count; } // Outputs a pointer to 'prev_wpi->next_', // where 'prev_wpi' is the pointer to the image at position (nth - 1). // Returns true if nth image was found. static int SearchImageToGetOrDelete(WebPMuxImage** wpi_list, uint32_t nth, WebPMuxImage*** const location) { uint32_t count = 0; assert(wpi_list); *location = wpi_list; if (nth == 0) { nth = MuxImageCount(*wpi_list, WEBP_CHUNK_NIL); if (nth == 0) return 0; // Not found. } while (*wpi_list != NULL) { WebPMuxImage* const cur_wpi = *wpi_list; ++count; if (count == nth) return 1; // Found. wpi_list = &cur_wpi->next_; *location = wpi_list; } return 0; // Not found. } //------------------------------------------------------------------------------ // MuxImage writer methods. WebPMuxError MuxImagePush(const WebPMuxImage* wpi, WebPMuxImage** wpi_list) { WebPMuxImage* new_wpi; while (*wpi_list != NULL) { WebPMuxImage* const cur_wpi = *wpi_list; if (cur_wpi->next_ == NULL) break; wpi_list = &cur_wpi->next_; } new_wpi = (WebPMuxImage*)WebPSafeMalloc(1ULL, sizeof(*new_wpi)); if (new_wpi == NULL) return WEBP_MUX_MEMORY_ERROR; *new_wpi = *wpi; new_wpi->next_ = NULL; if (*wpi_list != NULL) { (*wpi_list)->next_ = new_wpi; } else { *wpi_list = new_wpi; } return WEBP_MUX_OK; } //------------------------------------------------------------------------------ // MuxImage deletion methods. WebPMuxImage* MuxImageDelete(WebPMuxImage* const wpi) { // Delete the components of wpi. If wpi is NULL this is a noop. WebPMuxImage* const next = MuxImageRelease(wpi); WebPSafeFree(wpi); return next; } WebPMuxError MuxImageDeleteNth(WebPMuxImage** wpi_list, uint32_t nth) { assert(wpi_list); if (!SearchImageToGetOrDelete(wpi_list, nth, &wpi_list)) { return WEBP_MUX_NOT_FOUND; } *wpi_list = MuxImageDelete(*wpi_list); return WEBP_MUX_OK; } //------------------------------------------------------------------------------ // MuxImage reader methods. WebPMuxError MuxImageGetNth(const WebPMuxImage** wpi_list, uint32_t nth, WebPMuxImage** wpi) { assert(wpi_list); assert(wpi); if (!SearchImageToGetOrDelete((WebPMuxImage**)wpi_list, nth, (WebPMuxImage***)&wpi_list)) { return WEBP_MUX_NOT_FOUND; } *wpi = (WebPMuxImage*)*wpi_list; return WEBP_MUX_OK; } //------------------------------------------------------------------------------ // MuxImage serialization methods. // Size of an image. size_t MuxImageDiskSize(const WebPMuxImage* const wpi) { size_t size = 0; if (wpi->header_ != NULL) size += ChunkDiskSize(wpi->header_); if (wpi->alpha_ != NULL) size += ChunkDiskSize(wpi->alpha_); if (wpi->img_ != NULL) size += ChunkDiskSize(wpi->img_); if (wpi->unknown_ != NULL) size += ChunkListDiskSize(wpi->unknown_); return size; } // Special case as ANMF chunk encapsulates other image chunks. static uint8_t* ChunkEmitSpecial(const WebPChunk* const header, size_t total_size, uint8_t* dst) { const size_t header_size = header->data_.size; const size_t offset_to_next = total_size - CHUNK_HEADER_SIZE; assert(header->tag_ == kChunks[IDX_ANMF].tag); PutLE32(dst + 0, header->tag_); PutLE32(dst + TAG_SIZE, (uint32_t)offset_to_next); assert(header_size == (uint32_t)header_size); memcpy(dst + CHUNK_HEADER_SIZE, header->data_.bytes, header_size); if (header_size & 1) { dst[CHUNK_HEADER_SIZE + header_size] = 0; // Add padding. } return dst + ChunkDiskSize(header); } uint8_t* MuxImageEmit(const WebPMuxImage* const wpi, uint8_t* dst) { // Ordering of chunks to be emitted is strictly as follows: // 1. ANMF chunk (if present). // 2. ALPH chunk (if present). // 3. VP8/VP8L chunk. assert(wpi); if (wpi->header_ != NULL) { dst = ChunkEmitSpecial(wpi->header_, MuxImageDiskSize(wpi), dst); } if (wpi->alpha_ != NULL) dst = ChunkEmit(wpi->alpha_, dst); if (wpi->img_ != NULL) dst = ChunkEmit(wpi->img_, dst); if (wpi->unknown_ != NULL) dst = ChunkListEmit(wpi->unknown_, dst); return dst; } //------------------------------------------------------------------------------ // Helper methods for mux. int MuxHasAlpha(const WebPMuxImage* images) { while (images != NULL) { if (images->has_alpha_) return 1; images = images->next_; } return 0; } uint8_t* MuxEmitRiffHeader(uint8_t* const data, size_t size) { PutLE32(data + 0, MKFOURCC('R', 'I', 'F', 'F')); PutLE32(data + TAG_SIZE, (uint32_t)size - CHUNK_HEADER_SIZE); assert(size == (uint32_t)size); PutLE32(data + TAG_SIZE + CHUNK_SIZE_BYTES, MKFOURCC('W', 'E', 'B', 'P')); return data + RIFF_HEADER_SIZE; } WebPChunk** MuxGetChunkListFromId(const WebPMux* mux, WebPChunkId id) { assert(mux != NULL); switch (id) { case WEBP_CHUNK_VP8X: return (WebPChunk**)&mux->vp8x_; case WEBP_CHUNK_ICCP: return (WebPChunk**)&mux->iccp_; case WEBP_CHUNK_ANIM: return (WebPChunk**)&mux->anim_; case WEBP_CHUNK_EXIF: return (WebPChunk**)&mux->exif_; case WEBP_CHUNK_XMP: return (WebPChunk**)&mux->xmp_; default: return (WebPChunk**)&mux->unknown_; } } static int IsNotCompatible(int feature, int num_items) { return (feature != 0) != (num_items > 0); } #define NO_FLAG ((WebPFeatureFlags)0) // Test basic constraints: // retrieval, maximum number of chunks by index (use -1 to skip) // and feature incompatibility (use NO_FLAG to skip). // On success returns WEBP_MUX_OK and stores the chunk count in *num. static WebPMuxError ValidateChunk(const WebPMux* const mux, CHUNK_INDEX idx, WebPFeatureFlags feature, uint32_t vp8x_flags, int max, int* num) { const WebPMuxError err = WebPMuxNumChunks(mux, kChunks[idx].id, num); if (err != WEBP_MUX_OK) return err; if (max > -1 && *num > max) return WEBP_MUX_INVALID_ARGUMENT; if (feature != NO_FLAG && IsNotCompatible(vp8x_flags & feature, *num)) { return WEBP_MUX_INVALID_ARGUMENT; } return WEBP_MUX_OK; } WebPMuxError MuxValidate(const WebPMux* const mux) { int num_iccp; int num_exif; int num_xmp; int num_anim; int num_frames; int num_vp8x; int num_images; int num_alpha; uint32_t flags; WebPMuxError err; // Verify mux is not NULL. if (mux == NULL) return WEBP_MUX_INVALID_ARGUMENT; // Verify mux has at least one image. if (mux->images_ == NULL) return WEBP_MUX_INVALID_ARGUMENT; err = WebPMuxGetFeatures(mux, &flags); if (err != WEBP_MUX_OK) return err; // At most one color profile chunk. err = ValidateChunk(mux, IDX_ICCP, ICCP_FLAG, flags, 1, &num_iccp); if (err != WEBP_MUX_OK) return err; // At most one EXIF metadata. err = ValidateChunk(mux, IDX_EXIF, EXIF_FLAG, flags, 1, &num_exif); if (err != WEBP_MUX_OK) return err; // At most one XMP metadata. err = ValidateChunk(mux, IDX_XMP, XMP_FLAG, flags, 1, &num_xmp); if (err != WEBP_MUX_OK) return err; // Animation: ANIMATION_FLAG, ANIM chunk and ANMF chunk(s) are consistent. // At most one ANIM chunk. err = ValidateChunk(mux, IDX_ANIM, NO_FLAG, flags, 1, &num_anim); if (err != WEBP_MUX_OK) return err; err = ValidateChunk(mux, IDX_ANMF, NO_FLAG, flags, -1, &num_frames); if (err != WEBP_MUX_OK) return err; { const int has_animation = !!(flags & ANIMATION_FLAG); if (has_animation && (num_anim == 0 || num_frames == 0)) { return WEBP_MUX_INVALID_ARGUMENT; } if (!has_animation && (num_anim == 1 || num_frames > 0)) { return WEBP_MUX_INVALID_ARGUMENT; } if (!has_animation) { const WebPMuxImage* images = mux->images_; // There can be only one image. if (images == NULL || images->next_ != NULL) { return WEBP_MUX_INVALID_ARGUMENT; } // Size must match. if (mux->canvas_width_ > 0) { if (images->width_ != mux->canvas_width_ || images->height_ != mux->canvas_height_) { return WEBP_MUX_INVALID_ARGUMENT; } } } } // Verify either VP8X chunk is present OR there is only one elem in // mux->images_. err = ValidateChunk(mux, IDX_VP8X, NO_FLAG, flags, 1, &num_vp8x); if (err != WEBP_MUX_OK) return err; err = ValidateChunk(mux, IDX_VP8, NO_FLAG, flags, -1, &num_images); if (err != WEBP_MUX_OK) return err; if (num_vp8x == 0 && num_images != 1) return WEBP_MUX_INVALID_ARGUMENT; // ALPHA_FLAG & alpha chunk(s) are consistent. // Note: ALPHA_FLAG can be set when there is actually no Alpha data present. if (MuxHasAlpha(mux->images_)) { if (num_vp8x > 0) { // VP8X chunk is present, so it should contain ALPHA_FLAG. if (!(flags & ALPHA_FLAG)) return WEBP_MUX_INVALID_ARGUMENT; } else { // VP8X chunk is not present, so ALPH chunks should NOT be present either. err = WebPMuxNumChunks(mux, WEBP_CHUNK_ALPHA, &num_alpha); if (err != WEBP_MUX_OK) return err; if (num_alpha > 0) return WEBP_MUX_INVALID_ARGUMENT; } } return WEBP_MUX_OK; } #undef NO_FLAG //------------------------------------------------------------------------------