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;
}
// Delete all images in 'wpi_list'.
static void DeleteAllImages(WebPMuxImage** const wpi_list) {
while (*wpi_list != NULL) {
*wpi_list = MuxImageDelete(*wpi_list);
}
}
WebPMux* WebPMuxCreateInternal(const WebPData* bitstream, int copy_data,
int version) {
size_t riff_size;
uint32_t tag;
const uint8_t* end;
WebPMux* mux = NULL;
WebPMuxImage* wpi = NULL;
const uint8_t* data;
size_t size;
WebPChunk chunk;
ChunkInit(&chunk);
// Sanity checks.
if (WEBP_ABI_IS_INCOMPATIBLE(version, WEBP_MUX_ABI_VERSION)) {
return NULL; // version mismatch
}
if (bitstream == NULL) return NULL;
data = bitstream->bytes;
size = bitstream->size;
if (data == NULL) return NULL;
if (size < RIFF_HEADER_SIZE) return NULL;
if (GetLE32(data + 0) != MKFOURCC('R', 'I', 'F', 'F') ||
GetLE32(data + CHUNK_HEADER_SIZE) != MKFOURCC('W', 'E', 'B', 'P')) {
return NULL;
}
mux = WebPMuxNew();
if (mux == NULL) return NULL;
if (size < RIFF_HEADER_SIZE + TAG_SIZE) goto Err;
tag = GetLE32(data + RIFF_HEADER_SIZE);
if (tag != kChunks[IDX_VP8].tag &&
tag != kChunks[IDX_VP8L].tag &&
tag != kChunks[IDX_VP8X].tag) {
goto Err; // First chunk should be VP8, VP8L or VP8X.
}
riff_size = SizeWithPadding(GetLE32(data + TAG_SIZE));
if (riff_size > MAX_CHUNK_PAYLOAD || riff_size > size) {
goto Err;
} else {
if (riff_size < size) { // Redundant data after last chunk.
size = riff_size; // To make sure we don't read any data beyond mux_size.
}
}
end = data + size;
data += RIFF_HEADER_SIZE;
size -= RIFF_HEADER_SIZE;
wpi = (WebPMuxImage*)WebPSafeMalloc(1ULL, sizeof(*wpi));
if (wpi == NULL) goto Err;
MuxImageInit(wpi);
// Loop over chunks.
while (data != end) {
size_t data_size;
WebPChunkId id;
WebPChunk** chunk_list;
if (ChunkVerifyAndAssign(&chunk, data, size, riff_size,
copy_data) != WEBP_MUX_OK) {
goto Err;
}
data_size = ChunkDiskSize(&chunk);
id = ChunkGetIdFromTag(chunk.tag_);
switch (id) {
case WEBP_CHUNK_ALPHA:
if (wpi->alpha_ != NULL) goto Err; // Consecutive ALPH chunks.
if (ChunkSetNth(&chunk, &wpi->alpha_, 1) != WEBP_MUX_OK) goto Err;
wpi->is_partial_ = 1; // Waiting for a VP8 chunk.
break;
case WEBP_CHUNK_IMAGE:
if (ChunkSetNth(&chunk, &wpi->img_, 1) != WEBP_MUX_OK) goto Err;
if (!MuxImageFinalize(wpi)) goto Err;
wpi->is_partial_ = 0; // wpi is completely filled.
PushImage:
// Add this to mux->images_ list.
if (MuxImagePush(wpi, &mux->images_) != WEBP_MUX_OK) goto Err;
MuxImageInit(wpi); // Reset for reading next image.
break;
case WEBP_CHUNK_ANMF:
if (wpi->is_partial_) goto Err; // Previous wpi is still incomplete.
if (!MuxImageParse(&chunk, copy_data, wpi)) goto Err;
ChunkRelease(&chunk);
goto PushImage;
break;
default: // A non-image chunk.
if (wpi->is_partial_) goto Err; // Encountered a non-image chunk before
// getting all chunks of an image.
chunk_list = MuxGetChunkListFromId(mux, id); // List to add this chunk.
if (ChunkSetNth(&chunk, chunk_list, 0) != WEBP_MUX_OK) goto Err;
if (id == WEBP_CHUNK_VP8X) { // grab global specs
mux->canvas_width_ = GetLE24(data + 12) + 1;
mux->canvas_height_ = GetLE24(data + 15) + 1;
}
break;
}
data += data_size;
size -= data_size;
ChunkInit(&chunk);
}
// Validate mux if complete.
if (MuxValidate(mux) != WEBP_MUX_OK) goto Err;
MuxImageDelete(wpi);
return mux; // All OK;
Err: // Something bad happened.
ChunkRelease(&chunk);
MuxImageDelete(wpi);
WebPMuxDelete(mux);
return NULL;
}
void MuxImageDeleteAll(WebPMuxImage** const wpi_list) {
while (*wpi_list != NULL) {
*wpi_list = MuxImageDelete(*wpi_list);
}
}
