void /* PRIVATE */
png_push_read_IDAT(png_structp png_ptr)
{
#ifdef PNG_USE_LOCAL_ARRAYS
PNG_IDAT;
#endif
if (!(png_ptr->mode & PNG_HAVE_CHUNK_HEADER))
{
png_byte chunk_length[4];
if (png_ptr->buffer_size < 8)
{
png_push_save_buffer(png_ptr);
return;
}
png_push_fill_buffer(png_ptr, chunk_length, 4);
png_ptr->push_length = png_get_uint_31(png_ptr,chunk_length);
png_reset_crc(png_ptr);
png_crc_read(png_ptr, png_ptr->chunk_name, 4);
png_ptr->mode |= PNG_HAVE_CHUNK_HEADER;
if (png_memcmp(png_ptr->chunk_name, (png_bytep)png_IDAT, 4))
{
png_ptr->process_mode = PNG_READ_CHUNK_MODE;
if (!(png_ptr->flags & PNG_FLAG_ZLIB_FINISHED))
png_error(png_ptr, "Not enough compressed data");
return;
}
png_ptr->idat_size = png_ptr->push_length;
}
if (png_ptr->idat_size && png_ptr->save_buffer_size)
{
png_size_t save_size;
if (png_ptr->idat_size < (png_uint_32)png_ptr->save_buffer_size)
{
save_size = (png_size_t)png_ptr->idat_size;
/* check for overflow */
if((png_uint_32)save_size != png_ptr->idat_size)
png_error(png_ptr, "save_size overflowed in pngpread");
}
else
save_size = png_ptr->save_buffer_size;
png_calculate_crc(png_ptr, png_ptr->save_buffer_ptr, save_size);
if (!(png_ptr->flags & PNG_FLAG_ZLIB_FINISHED))
png_process_IDAT_data(png_ptr, png_ptr->save_buffer_ptr, save_size);
png_ptr->idat_size -= save_size;
png_ptr->buffer_size -= save_size;
png_ptr->save_buffer_size -= save_size;
png_ptr->save_buffer_ptr += save_size;
}
if (png_ptr->idat_size && png_ptr->current_buffer_size)
{
png_size_t save_size;
if (png_ptr->idat_size < (png_uint_32)png_ptr->current_buffer_size)
{
save_size = (png_size_t)png_ptr->idat_size;
/* check for overflow */
if((png_uint_32)save_size != png_ptr->idat_size)
png_error(png_ptr, "save_size overflowed in pngpread");
}
else
save_size = png_ptr->current_buffer_size;
png_calculate_crc(png_ptr, png_ptr->current_buffer_ptr, save_size);
if (!(png_ptr->flags & PNG_FLAG_ZLIB_FINISHED))
png_process_IDAT_data(png_ptr, png_ptr->current_buffer_ptr, save_size);
png_ptr->idat_size -= save_size;
png_ptr->buffer_size -= save_size;
png_ptr->current_buffer_size -= save_size;
png_ptr->current_buffer_ptr += save_size;
}
if (!png_ptr->idat_size)
{
if (png_ptr->buffer_size < 4)
{
png_push_save_buffer(png_ptr);
return;
}
png_crc_finish(png_ptr, 0);
png_ptr->mode &= ~PNG_HAVE_CHUNK_HEADER;
png_ptr->mode |= PNG_AFTER_IDAT;
}
}
void /* PRIVATE */
png_push_read_chunk(png_structrp png_ptr, png_inforp info_ptr)
{
png_uint_32 chunk_name;
#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
int keep; /* unknown handling method */
#endif
/* First we make sure we have enough data for the 4-byte chunk name
* and the 4-byte chunk length before proceeding with decoding the
* chunk data. To fully decode each of these chunks, we also make
* sure we have enough data in the buffer for the 4-byte CRC at the
* end of every chunk (except IDAT, which is handled separately).
*/
if ((png_ptr->mode & PNG_HAVE_CHUNK_HEADER) == 0)
{
png_byte chunk_length[4];
png_byte chunk_tag[4];
PNG_PUSH_SAVE_BUFFER_IF_LT(8)
png_push_fill_buffer(png_ptr, chunk_length, 4);
png_ptr->push_length = png_get_uint_31(png_ptr, chunk_length);
png_reset_crc(png_ptr);
png_crc_read(png_ptr, chunk_tag, 4);
png_ptr->chunk_name = PNG_CHUNK_FROM_STRING(chunk_tag);
png_check_chunk_name(png_ptr, png_ptr->chunk_name);
png_ptr->mode |= PNG_HAVE_CHUNK_HEADER;
}
chunk_name = png_ptr->chunk_name;
#ifdef PNG_READ_APNG_SUPPORTED
if (png_ptr->num_frames_read > 0 &&
png_ptr->num_frames_read < info_ptr->num_frames)
{
if (chunk_name == png_IDAT)
{
/* Discard trailing IDATs for the first frame */
if (png_ptr->mode & PNG_HAVE_fcTL || png_ptr->num_frames_read > 1)
png_error(png_ptr, "out of place IDAT");
if (png_ptr->push_length + 4 > png_ptr->buffer_size)
{
png_push_save_buffer(png_ptr);
return;
}
png_ptr->mode &= ~PNG_HAVE_CHUNK_HEADER;
return;
}
else if (chunk_name == png_fdAT)
{
if (png_ptr->buffer_size < 4)
{
png_push_save_buffer(png_ptr);
return;
}
png_ensure_sequence_number(png_ptr, 4);
if (!(png_ptr->mode & PNG_HAVE_fcTL))
{
/* Discard trailing fdATs for frames other than the first */
if (png_ptr->num_frames_read < 2)
png_error(png_ptr, "out of place fdAT");
if (png_ptr->push_length + 4 > png_ptr->buffer_size)
{
png_push_save_buffer(png_ptr);
return;
}
png_ptr->mode &= ~PNG_HAVE_CHUNK_HEADER;
return;
}
else
{
/* frame data follows */
png_ptr->idat_size = png_ptr->push_length - 4;
png_ptr->mode |= PNG_HAVE_IDAT;
png_ptr->process_mode = PNG_READ_IDAT_MODE;
return;
}
}
else if (chunk_name == png_fcTL)
{
if (png_ptr->push_length + 4 > png_ptr->buffer_size)
{
png_push_save_buffer(png_ptr);
return;
}
png_read_reset(png_ptr);
png_ptr->mode &= ~PNG_HAVE_fcTL;
png_handle_fcTL(png_ptr, info_ptr, png_ptr->push_length);
if (!(png_ptr->mode & PNG_HAVE_fcTL))
png_error(png_ptr, "missing required fcTL chunk");
png_read_reinit(png_ptr, info_ptr);
png_progressive_read_reset(png_ptr);
if (png_ptr->frame_info_fn != NULL)
(*(png_ptr->frame_info_fn))(png_ptr, png_ptr->num_frames_read);
png_ptr->mode &= ~PNG_HAVE_CHUNK_HEADER;
return;
}
else
{
if (png_ptr->push_length + 4 > png_ptr->buffer_size)
{
png_push_save_buffer(png_ptr);
return;
}
png_warning(png_ptr, "Skipped (ignored) a chunk "
"between APNG chunks");
png_ptr->mode &= ~PNG_HAVE_CHUNK_HEADER;
return;
}
return;
}
#endif /* PNG_READ_APNG_SUPPORTED */
if (chunk_name == png_IDAT)
{
if ((png_ptr->mode & PNG_AFTER_IDAT) != 0)
png_ptr->mode |= PNG_HAVE_CHUNK_AFTER_IDAT;
/* If we reach an IDAT chunk, this means we have read all of the
* header chunks, and we can start reading the image (or if this
* is called after the image has been read - we have an error).
*/
if ((png_ptr->mode & PNG_HAVE_IHDR) == 0)
png_error(png_ptr, "Missing IHDR before IDAT");
else if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE &&
(png_ptr->mode & PNG_HAVE_PLTE) == 0)
png_error(png_ptr, "Missing PLTE before IDAT");
png_ptr->process_mode = PNG_READ_IDAT_MODE;
if ((png_ptr->mode & PNG_HAVE_IDAT) != 0)
if ((png_ptr->mode & PNG_HAVE_CHUNK_AFTER_IDAT) == 0)
if (png_ptr->push_length == 0)
return;
png_ptr->mode |= PNG_HAVE_IDAT;
if ((png_ptr->mode & PNG_AFTER_IDAT) != 0)
png_benign_error(png_ptr, "Too many IDATs found");
}
if (chunk_name == png_IHDR)
{
if (png_ptr->push_length != 13)
png_error(png_ptr, "Invalid IHDR length");
PNG_PUSH_SAVE_BUFFER_IF_FULL
png_handle_IHDR(png_ptr, info_ptr, png_ptr->push_length);
}
else if (chunk_name == png_IEND)
{
PNG_PUSH_SAVE_BUFFER_IF_FULL
png_handle_IEND(png_ptr, info_ptr, png_ptr->push_length);
png_ptr->process_mode = PNG_READ_DONE_MODE;
png_push_have_end(png_ptr, info_ptr);
}
#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
else if ((keep = png_chunk_unknown_handling(png_ptr, chunk_name)) != 0)
{
PNG_PUSH_SAVE_BUFFER_IF_FULL
png_handle_unknown(png_ptr, info_ptr, png_ptr->push_length, keep);
if (chunk_name == png_PLTE)
png_ptr->mode |= PNG_HAVE_PLTE;
}
#endif
else if (chunk_name == png_PLTE)
{
PNG_PUSH_SAVE_BUFFER_IF_FULL
png_handle_PLTE(png_ptr, info_ptr, png_ptr->push_length);
}
else if (chunk_name == png_IDAT)
{
#ifdef PNG_READ_APNG_SUPPORTED
png_have_info(png_ptr, info_ptr);
#endif
png_ptr->idat_size = png_ptr->push_length;
png_ptr->process_mode = PNG_READ_IDAT_MODE;
png_push_have_info(png_ptr, info_ptr);
png_ptr->zstream.avail_out =
(uInt) PNG_ROWBYTES(png_ptr->pixel_depth,
png_ptr->iwidth) + 1;
png_ptr->zstream.next_out = png_ptr->row_buf;
return;
}
#ifdef PNG_READ_gAMA_SUPPORTED
else if (png_ptr->chunk_name == png_gAMA)
{
PNG_PUSH_SAVE_BUFFER_IF_FULL
png_handle_gAMA(png_ptr, info_ptr, png_ptr->push_length);
}
#endif
#ifdef PNG_READ_sBIT_SUPPORTED
else if (png_ptr->chunk_name == png_sBIT)
{
PNG_PUSH_SAVE_BUFFER_IF_FULL
png_handle_sBIT(png_ptr, info_ptr, png_ptr->push_length);
}
#endif
#ifdef PNG_READ_cHRM_SUPPORTED
else if (png_ptr->chunk_name == png_cHRM)
{
PNG_PUSH_SAVE_BUFFER_IF_FULL
png_handle_cHRM(png_ptr, info_ptr, png_ptr->push_length);
}
#endif
#ifdef PNG_READ_sRGB_SUPPORTED
else if (chunk_name == png_sRGB)
{
PNG_PUSH_SAVE_BUFFER_IF_FULL
png_handle_sRGB(png_ptr, info_ptr, png_ptr->push_length);
}
#endif
#ifdef PNG_READ_iCCP_SUPPORTED
else if (png_ptr->chunk_name == png_iCCP)
{
PNG_PUSH_SAVE_BUFFER_IF_FULL
png_handle_iCCP(png_ptr, info_ptr, png_ptr->push_length);
}
#endif
#ifdef PNG_READ_sPLT_SUPPORTED
else if (chunk_name == png_sPLT)
{
PNG_PUSH_SAVE_BUFFER_IF_FULL
png_handle_sPLT(png_ptr, info_ptr, png_ptr->push_length);
}
#endif
#ifdef PNG_READ_tRNS_SUPPORTED
else if (chunk_name == png_tRNS)
{
PNG_PUSH_SAVE_BUFFER_IF_FULL
png_handle_tRNS(png_ptr, info_ptr, png_ptr->push_length);
}
#endif
#ifdef PNG_READ_bKGD_SUPPORTED
else if (chunk_name == png_bKGD)
{
PNG_PUSH_SAVE_BUFFER_IF_FULL
png_handle_bKGD(png_ptr, info_ptr, png_ptr->push_length);
}
#endif
#ifdef PNG_READ_hIST_SUPPORTED
else if (chunk_name == png_hIST)
{
PNG_PUSH_SAVE_BUFFER_IF_FULL
png_handle_hIST(png_ptr, info_ptr, png_ptr->push_length);
}
#endif
#ifdef PNG_READ_pHYs_SUPPORTED
else if (chunk_name == png_pHYs)
{
PNG_PUSH_SAVE_BUFFER_IF_FULL
png_handle_pHYs(png_ptr, info_ptr, png_ptr->push_length);
}
#endif
#ifdef PNG_READ_oFFs_SUPPORTED
else if (chunk_name == png_oFFs)
{
PNG_PUSH_SAVE_BUFFER_IF_FULL
png_handle_oFFs(png_ptr, info_ptr, png_ptr->push_length);
}
#endif
#ifdef PNG_READ_pCAL_SUPPORTED
else if (chunk_name == png_pCAL)
{
PNG_PUSH_SAVE_BUFFER_IF_FULL
png_handle_pCAL(png_ptr, info_ptr, png_ptr->push_length);
}
#endif
#ifdef PNG_READ_sCAL_SUPPORTED
else if (chunk_name == png_sCAL)
{
PNG_PUSH_SAVE_BUFFER_IF_FULL
png_handle_sCAL(png_ptr, info_ptr, png_ptr->push_length);
}
#endif
#ifdef PNG_READ_tIME_SUPPORTED
else if (chunk_name == png_tIME)
{
PNG_PUSH_SAVE_BUFFER_IF_FULL
png_handle_tIME(png_ptr, info_ptr, png_ptr->push_length);
}
#endif
#ifdef PNG_READ_tEXt_SUPPORTED
else if (chunk_name == png_tEXt)
{
PNG_PUSH_SAVE_BUFFER_IF_FULL
png_handle_tEXt(png_ptr, info_ptr, png_ptr->push_length);
}
#endif
#ifdef PNG_READ_zTXt_SUPPORTED
else if (chunk_name == png_zTXt)
{
PNG_PUSH_SAVE_BUFFER_IF_FULL
png_handle_zTXt(png_ptr, info_ptr, png_ptr->push_length);
}
#endif
#ifdef PNG_READ_iTXt_SUPPORTED
else if (chunk_name == png_iTXt)
{
PNG_PUSH_SAVE_BUFFER_IF_FULL
png_handle_iTXt(png_ptr, info_ptr, png_ptr->push_length);
}
#endif
#ifdef PNG_READ_APNG_SUPPORTED
else if (chunk_name == png_acTL)
{
if (png_ptr->push_length + 4 > png_ptr->buffer_size)
{
png_push_save_buffer(png_ptr);
return;
}
png_handle_acTL(png_ptr, info_ptr, png_ptr->push_length);
}
else if (chunk_name == png_fcTL)
{
if (png_ptr->push_length + 4 > png_ptr->buffer_size)
{
png_push_save_buffer(png_ptr);
return;
}
png_handle_fcTL(png_ptr, info_ptr, png_ptr->push_length);
}
#endif /* PNG_READ_APNG_SUPPORTED */
else
{
PNG_PUSH_SAVE_BUFFER_IF_FULL
png_handle_unknown(png_ptr, info_ptr, png_ptr->push_length,
PNG_HANDLE_CHUNK_AS_DEFAULT);
}
png_ptr->mode &= ~PNG_HAVE_CHUNK_HEADER;
}
void /* PRIVATE */
png_push_read_IDAT(png_structrp png_ptr)
{
if ((png_ptr->mode & PNG_HAVE_CHUNK_HEADER) == 0)
{
png_byte chunk_length[4];
png_byte chunk_tag[4];
/* TODO: this code can be commoned up with the same code in push_read */
#ifdef PNG_READ_APNG_SUPPORTED
PNG_PUSH_SAVE_BUFFER_IF_LT(12)
#else
PNG_PUSH_SAVE_BUFFER_IF_LT(8)
#endif
png_push_fill_buffer(png_ptr, chunk_length, 4);
png_ptr->push_length = png_get_uint_31(png_ptr, chunk_length);
png_reset_crc(png_ptr);
png_crc_read(png_ptr, chunk_tag, 4);
png_ptr->chunk_name = PNG_CHUNK_FROM_STRING(chunk_tag);
png_ptr->mode |= PNG_HAVE_CHUNK_HEADER;
#ifdef PNG_READ_APNG_SUPPORTED
if (png_ptr->chunk_name != png_fdAT && png_ptr->num_frames_read > 0)
{
if ((png_ptr->flags & PNG_FLAG_ZSTREAM_ENDED) != 0)
{
png_ptr->process_mode = PNG_READ_CHUNK_MODE;
if (png_ptr->frame_end_fn != NULL)
(*(png_ptr->frame_end_fn))(png_ptr, png_ptr->num_frames_read);
png_ptr->num_frames_read++;
return;
}
else
{
if (png_ptr->chunk_name == png_IEND)
png_error(png_ptr, "Not enough image data");
PNG_PUSH_SAVE_BUFFER_IF_FULL
png_warning(png_ptr, "Skipping (ignoring) a chunk between "
"APNG chunks");
png_crc_finish(png_ptr, png_ptr->push_length);
png_ptr->mode &= ~PNG_HAVE_CHUNK_HEADER;
return;
}
}
else
#endif
#ifdef PNG_READ_APNG_SUPPORTED
if (png_ptr->chunk_name != png_IDAT && png_ptr->num_frames_read == 0)
#else
if (png_ptr->chunk_name != png_IDAT)
#endif
{
png_ptr->process_mode = PNG_READ_CHUNK_MODE;
if ((png_ptr->flags & PNG_FLAG_ZSTREAM_ENDED) == 0)
png_error(png_ptr, "Not enough compressed data");
#ifdef PNG_READ_APNG_SUPPORTED
if (png_ptr->frame_end_fn != NULL)
(*(png_ptr->frame_end_fn))(png_ptr, png_ptr->num_frames_read);
png_ptr->num_frames_read++;
#endif
return;
}
png_ptr->idat_size = png_ptr->push_length;
#ifdef PNG_READ_APNG_SUPPORTED
if (png_ptr->num_frames_read > 0)
{
png_ensure_sequence_number(png_ptr, 4);
png_ptr->idat_size -= 4;
}
#endif
}
if (png_ptr->idat_size != 0 && png_ptr->save_buffer_size != 0)
{
png_size_t save_size = png_ptr->save_buffer_size;
png_uint_32 idat_size = png_ptr->idat_size;
/* We want the smaller of 'idat_size' and 'current_buffer_size', but they
* are of different types and we don't know which variable has the fewest
* bits. Carefully select the smaller and cast it to the type of the
* larger - this cannot overflow. Do not cast in the following test - it
* will break on either 16-bit or 64-bit platforms.
*/
if (idat_size < save_size)
save_size = (png_size_t)idat_size;
else
idat_size = (png_uint_32)save_size;
png_calculate_crc(png_ptr, png_ptr->save_buffer_ptr, save_size);
png_process_IDAT_data(png_ptr, png_ptr->save_buffer_ptr, save_size);
png_ptr->idat_size -= idat_size;
png_ptr->buffer_size -= save_size;
png_ptr->save_buffer_size -= save_size;
png_ptr->save_buffer_ptr += save_size;
}
if (png_ptr->idat_size != 0 && png_ptr->current_buffer_size != 0)
{
png_size_t save_size = png_ptr->current_buffer_size;
png_uint_32 idat_size = png_ptr->idat_size;
/* We want the smaller of 'idat_size' and 'current_buffer_size', but they
* are of different types and we don't know which variable has the fewest
* bits. Carefully select the smaller and cast it to the type of the
* larger - this cannot overflow.
*/
if (idat_size < save_size)
save_size = (png_size_t)idat_size;
else
idat_size = (png_uint_32)save_size;
png_calculate_crc(png_ptr, png_ptr->current_buffer_ptr, save_size);
png_process_IDAT_data(png_ptr, png_ptr->current_buffer_ptr, save_size);
png_ptr->idat_size -= idat_size;
png_ptr->buffer_size -= save_size;
png_ptr->current_buffer_size -= save_size;
png_ptr->current_buffer_ptr += save_size;
}
if (png_ptr->idat_size == 0)
{
PNG_PUSH_SAVE_BUFFER_IF_LT(4)
png_crc_finish(png_ptr, 0);
png_ptr->mode &= ~PNG_HAVE_CHUNK_HEADER;
png_ptr->mode |= PNG_AFTER_IDAT;
png_ptr->zowner = 0;
}
}
void /* PRIVATE */
png_push_read_chunk(png_structp png_ptr, png_infop info_ptr)
{
#ifdef PNG_USE_LOCAL_ARRAYS
PNG_IHDR;
PNG_IDAT;
PNG_IEND;
PNG_PLTE;
#if defined(PNG_READ_bKGD_SUPPORTED)
PNG_bKGD;
#endif
#if defined(PNG_READ_cHRM_SUPPORTED)
PNG_cHRM;
#endif
#if defined(PNG_READ_gAMA_SUPPORTED)
PNG_gAMA;
#endif
#if defined(PNG_READ_hIST_SUPPORTED)
PNG_hIST;
#endif
#if defined(PNG_READ_iCCP_SUPPORTED)
PNG_iCCP;
#endif
#if defined(PNG_READ_iTXt_SUPPORTED)
PNG_iTXt;
#endif
#if defined(PNG_READ_oFFs_SUPPORTED)
PNG_oFFs;
#endif
#if defined(PNG_READ_pCAL_SUPPORTED)
PNG_pCAL;
#endif
#if defined(PNG_READ_pHYs_SUPPORTED)
PNG_pHYs;
#endif
#if defined(PNG_READ_sBIT_SUPPORTED)
PNG_sBIT;
#endif
#if defined(PNG_READ_sCAL_SUPPORTED)
PNG_sCAL;
#endif
#if defined(PNG_READ_sRGB_SUPPORTED)
PNG_sRGB;
#endif
#if defined(PNG_READ_sPLT_SUPPORTED)
PNG_sPLT;
#endif
#if defined(PNG_READ_tEXt_SUPPORTED)
PNG_tEXt;
#endif
#if defined(PNG_READ_tIME_SUPPORTED)
PNG_tIME;
#endif
#if defined(PNG_READ_tRNS_SUPPORTED)
PNG_tRNS;
#endif
#if defined(PNG_READ_zTXt_SUPPORTED)
PNG_zTXt;
#endif
#endif /* PNG_USE_LOCAL_ARRAYS */
/* First we make sure we have enough data for the 4 byte chunk name
* and the 4 byte chunk length before proceeding with decoding the
* chunk data. To fully decode each of these chunks, we also make
* sure we have enough data in the buffer for the 4 byte CRC at the
* end of every chunk (except IDAT, which is handled separately).
*/
if (!(png_ptr->mode & PNG_HAVE_CHUNK_HEADER))
{
png_byte chunk_length[4];
if (png_ptr->buffer_size < 8)
{
png_push_save_buffer(png_ptr);
return;
}
png_push_fill_buffer(png_ptr, chunk_length, 4);
png_ptr->push_length = png_get_uint_31(png_ptr,chunk_length);
png_reset_crc(png_ptr);
png_crc_read(png_ptr, png_ptr->chunk_name, 4);
png_ptr->mode |= PNG_HAVE_CHUNK_HEADER;
}
if (!png_memcmp(png_ptr->chunk_name, png_IHDR, 4))
{
if (png_ptr->push_length + 4 > png_ptr->buffer_size)
{
png_push_save_buffer(png_ptr);
return;
}
png_handle_IHDR(png_ptr, info_ptr, png_ptr->push_length);
}
else if (!png_memcmp(png_ptr->chunk_name, png_IEND, 4))
{
if (png_ptr->push_length + 4 > png_ptr->buffer_size)
{
png_push_save_buffer(png_ptr);
return;
}
png_handle_IEND(png_ptr, info_ptr, png_ptr->push_length);
png_ptr->process_mode = PNG_READ_DONE_MODE;
png_push_have_end(png_ptr, info_ptr);
}
#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
else if (png_handle_as_unknown(png_ptr, png_ptr->chunk_name))
{
if (png_ptr->push_length + 4 > png_ptr->buffer_size)
{
png_push_save_buffer(png_ptr);
return;
}
if (!png_memcmp(png_ptr->chunk_name, png_IDAT, 4))
png_ptr->mode |= PNG_HAVE_IDAT;
png_handle_unknown(png_ptr, info_ptr, png_ptr->push_length);
if (!png_memcmp(png_ptr->chunk_name, png_PLTE, 4))
png_ptr->mode |= PNG_HAVE_PLTE;
else if (!png_memcmp(png_ptr->chunk_name, png_IDAT, 4))
{
if (!(png_ptr->mode & PNG_HAVE_IHDR))
png_error(png_ptr, "Missing IHDR before IDAT");
else if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE &&
!(png_ptr->mode & PNG_HAVE_PLTE))
png_error(png_ptr, "Missing PLTE before IDAT");
}
}
#endif
else if (!png_memcmp(png_ptr->chunk_name, png_PLTE, 4))
{
if (png_ptr->push_length + 4 > png_ptr->buffer_size)
{
png_push_save_buffer(png_ptr);
return;
}
png_handle_PLTE(png_ptr, info_ptr, png_ptr->push_length);
}
else if (!png_memcmp(png_ptr->chunk_name, (png_bytep)png_IDAT, 4))
{
/* If we reach an IDAT chunk, this means we have read all of the
* header chunks, and we can start reading the image (or if this
* is called after the image has been read - we have an error).
*/
if (!(png_ptr->mode & PNG_HAVE_IHDR))
png_error(png_ptr, "Missing IHDR before IDAT");
else if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE &&
!(png_ptr->mode & PNG_HAVE_PLTE))
png_error(png_ptr, "Missing PLTE before IDAT");
if (png_ptr->mode & PNG_HAVE_IDAT)
{
if (png_ptr->push_length == 0)
return;
if (png_ptr->mode & PNG_AFTER_IDAT)
png_error(png_ptr, "Too many IDAT's found");
}
png_ptr->idat_size = png_ptr->push_length;
png_ptr->mode |= PNG_HAVE_IDAT;
png_ptr->process_mode = PNG_READ_IDAT_MODE;
png_push_have_info(png_ptr, info_ptr);
png_ptr->zstream.avail_out = (uInt)png_ptr->irowbytes;
png_ptr->zstream.next_out = png_ptr->row_buf;
return;
}
#if defined(PNG_READ_gAMA_SUPPORTED)
else if (!png_memcmp(png_ptr->chunk_name, png_gAMA, 4))
{
if (png_ptr->push_length + 4 > png_ptr->buffer_size)
{
png_push_save_buffer(png_ptr);
return;
}
png_handle_gAMA(png_ptr, info_ptr, png_ptr->push_length);
}
#endif
#if defined(PNG_READ_sBIT_SUPPORTED)
else if (!png_memcmp(png_ptr->chunk_name, png_sBIT, 4))
{
if (png_ptr->push_length + 4 > png_ptr->buffer_size)
{
png_push_save_buffer(png_ptr);
return;
}
png_handle_sBIT(png_ptr, info_ptr, png_ptr->push_length);
}
#endif
#if defined(PNG_READ_cHRM_SUPPORTED)
else if (!png_memcmp(png_ptr->chunk_name, png_cHRM, 4))
{
if (png_ptr->push_length + 4 > png_ptr->buffer_size)
{
png_push_save_buffer(png_ptr);
return;
}
png_handle_cHRM(png_ptr, info_ptr, png_ptr->push_length);
}
#endif
#if defined(PNG_READ_sRGB_SUPPORTED)
else if (!png_memcmp(png_ptr->chunk_name, png_sRGB, 4))
{
if (png_ptr->push_length + 4 > png_ptr->buffer_size)
{
png_push_save_buffer(png_ptr);
return;
}
png_handle_sRGB(png_ptr, info_ptr, png_ptr->push_length);
}
#endif
#if defined(PNG_READ_iCCP_SUPPORTED)
else if (!png_memcmp(png_ptr->chunk_name, png_iCCP, 4))
{
if (png_ptr->push_length + 4 > png_ptr->buffer_size)
{
png_push_save_buffer(png_ptr);
return;
}
png_handle_iCCP(png_ptr, info_ptr, png_ptr->push_length);
}
#endif
#if defined(PNG_READ_sPLT_SUPPORTED)
else if (!png_memcmp(png_ptr->chunk_name, png_sPLT, 4))
{
if (png_ptr->push_length + 4 > png_ptr->buffer_size)
{
png_push_save_buffer(png_ptr);
return;
}
png_handle_sPLT(png_ptr, info_ptr, png_ptr->push_length);
}
#endif
#if defined(PNG_READ_tRNS_SUPPORTED)
else if (!png_memcmp(png_ptr->chunk_name, png_tRNS, 4))
{
if (png_ptr->push_length + 4 > png_ptr->buffer_size)
{
png_push_save_buffer(png_ptr);
return;
}
png_handle_tRNS(png_ptr, info_ptr, png_ptr->push_length);
}
#endif
#if defined(PNG_READ_bKGD_SUPPORTED)
else if (!png_memcmp(png_ptr->chunk_name, png_bKGD, 4))
{
if (png_ptr->push_length + 4 > png_ptr->buffer_size)
{
png_push_save_buffer(png_ptr);
return;
}
png_handle_bKGD(png_ptr, info_ptr, png_ptr->push_length);
}
#endif
#if defined(PNG_READ_hIST_SUPPORTED)
else if (!png_memcmp(png_ptr->chunk_name, png_hIST, 4))
{
if (png_ptr->push_length + 4 > png_ptr->buffer_size)
{
png_push_save_buffer(png_ptr);
return;
}
png_handle_hIST(png_ptr, info_ptr, png_ptr->push_length);
}
#endif
#if defined(PNG_READ_pHYs_SUPPORTED)
else if (!png_memcmp(png_ptr->chunk_name, png_pHYs, 4))
{
if (png_ptr->push_length + 4 > png_ptr->buffer_size)
{
png_push_save_buffer(png_ptr);
return;
}
png_handle_pHYs(png_ptr, info_ptr, png_ptr->push_length);
}
#endif
#if defined(PNG_READ_oFFs_SUPPORTED)
else if (!png_memcmp(png_ptr->chunk_name, png_oFFs, 4))
{
if (png_ptr->push_length + 4 > png_ptr->buffer_size)
{
png_push_save_buffer(png_ptr);
return;
}
png_handle_oFFs(png_ptr, info_ptr, png_ptr->push_length);
}
#endif
#if defined(PNG_READ_pCAL_SUPPORTED)
else if (!png_memcmp(png_ptr->chunk_name, png_pCAL, 4))
{
if (png_ptr->push_length + 4 > png_ptr->buffer_size)
{
png_push_save_buffer(png_ptr);
return;
}
png_handle_pCAL(png_ptr, info_ptr, png_ptr->push_length);
}
#endif
#if defined(PNG_READ_sCAL_SUPPORTED)
else if (!png_memcmp(png_ptr->chunk_name, png_sCAL, 4))
{
if (png_ptr->push_length + 4 > png_ptr->buffer_size)
{
png_push_save_buffer(png_ptr);
return;
}
png_handle_sCAL(png_ptr, info_ptr, png_ptr->push_length);
}
#endif
#if defined(PNG_READ_tIME_SUPPORTED)
else if (!png_memcmp(png_ptr->chunk_name, png_tIME, 4))
{
if (png_ptr->push_length + 4 > png_ptr->buffer_size)
{
png_push_save_buffer(png_ptr);
return;
}
png_handle_tIME(png_ptr, info_ptr, png_ptr->push_length);
}
#endif
#if defined(PNG_READ_tEXt_SUPPORTED)
else if (!png_memcmp(png_ptr->chunk_name, png_tEXt, 4))
{
if (png_ptr->push_length + 4 > png_ptr->buffer_size)
{
png_push_save_buffer(png_ptr);
return;
}
png_push_handle_tEXt(png_ptr, info_ptr, png_ptr->push_length);
}
#endif
#if defined(PNG_READ_zTXt_SUPPORTED)
else if (!png_memcmp(png_ptr->chunk_name, png_zTXt, 4))
{
if (png_ptr->push_length + 4 > png_ptr->buffer_size)
{
png_push_save_buffer(png_ptr);
return;
}
png_push_handle_zTXt(png_ptr, info_ptr, png_ptr->push_length);
}
#endif
#if defined(PNG_READ_iTXt_SUPPORTED)
else if (!png_memcmp(png_ptr->chunk_name, png_iTXt, 4))
{
if (png_ptr->push_length + 4 > png_ptr->buffer_size)
{
png_push_save_buffer(png_ptr);
return;
}
png_push_handle_iTXt(png_ptr, info_ptr, png_ptr->push_length);
}
#endif
else
{
if (png_ptr->push_length + 4 > png_ptr->buffer_size)
{
png_push_save_buffer(png_ptr);
return;
}
png_push_handle_unknown(png_ptr, info_ptr, png_ptr->push_length);
}
png_ptr->mode &= ~PNG_HAVE_CHUNK_HEADER;
}
void /* PRIVATE */
png_push_read_IDAT(png_structp png_ptr)
{
PNG_IDAT;
if (!(png_ptr->mode & PNG_HAVE_CHUNK_HEADER))
{
png_byte chunk_length[4];
if (png_ptr->buffer_size < 8)
{
png_push_save_buffer(png_ptr);
return;
}
png_push_fill_buffer(png_ptr, chunk_length, 4);
png_ptr->push_length = png_get_uint_31(png_ptr, chunk_length);
png_reset_crc(png_ptr);
png_crc_read(png_ptr, png_ptr->chunk_name, 4);
png_ptr->mode |= PNG_HAVE_CHUNK_HEADER;
if (png_memcmp(png_ptr->chunk_name, png_IDAT, 4))
{
png_ptr->process_mode = PNG_READ_CHUNK_MODE;
if (!(png_ptr->flags & PNG_FLAG_ZLIB_FINISHED))
png_error(png_ptr, "Not enough compressed data");
return;
}
png_ptr->idat_size = png_ptr->push_length;
}
if (png_ptr->idat_size && png_ptr->save_buffer_size)
{
png_size_t save_size = png_ptr->save_buffer_size;
png_uint_32 idat_size = png_ptr->idat_size;
/* We want the smaller of 'idat_size' and 'current_buffer_size', but they
* are of different types and we don't know which variable has the fewest
* bits. Carefully select the smaller and cast it to the type of the
* larger - this cannot overflow. Do not cast in the following test - it
* will break on either 16 or 64 bit platforms.
*/
if (idat_size < save_size)
save_size = (png_size_t)idat_size;
else
idat_size = (png_uint_32)save_size;
png_calculate_crc(png_ptr, png_ptr->save_buffer_ptr, save_size);
png_process_IDAT_data(png_ptr, png_ptr->save_buffer_ptr, save_size);
png_ptr->idat_size -= idat_size;
png_ptr->buffer_size -= save_size;
png_ptr->save_buffer_size -= save_size;
png_ptr->save_buffer_ptr += save_size;
}
if (png_ptr->idat_size && png_ptr->current_buffer_size)
{
png_size_t save_size = png_ptr->current_buffer_size;
png_uint_32 idat_size = png_ptr->idat_size;
/* We want the smaller of 'idat_size' and 'current_buffer_size', but they
* are of different types and we don't know which variable has the fewest
* bits. Carefully select the smaller and cast it to the type of the
* larger - this cannot overflow.
*/
if (idat_size < save_size)
save_size = (png_size_t)idat_size;
else
idat_size = (png_uint_32)save_size;
png_calculate_crc(png_ptr, png_ptr->current_buffer_ptr, save_size);
png_process_IDAT_data(png_ptr, png_ptr->current_buffer_ptr, save_size);
png_ptr->idat_size -= idat_size;
png_ptr->buffer_size -= save_size;
png_ptr->current_buffer_size -= save_size;
png_ptr->current_buffer_ptr += save_size;
}
if (!png_ptr->idat_size)
{
if (png_ptr->buffer_size < 4)
{
png_push_save_buffer(png_ptr);
return;
}
png_crc_finish(png_ptr, 0);
png_ptr->mode &= ~PNG_HAVE_CHUNK_HEADER;
png_ptr->mode |= PNG_AFTER_IDAT;
}
}
void /* PRIVATE */
png_push_read_IDAT(png_structrp png_ptr)
{
if ((png_ptr->mode & PNG_HAVE_CHUNK_HEADER) == 0)
{
png_byte chunk_length[4];
png_byte chunk_tag[4];
/* TODO: this code can be commoned up with the same code in push_read */
PNG_PUSH_SAVE_BUFFER_IF_LT(8)
png_push_fill_buffer(png_ptr, chunk_length, 4);
png_ptr->push_length = png_get_uint_31(png_ptr, chunk_length);
png_reset_crc(png_ptr);
png_crc_read(png_ptr, chunk_tag, 4);
png_ptr->chunk_name = PNG_CHUNK_FROM_STRING(chunk_tag);
png_ptr->mode |= PNG_HAVE_CHUNK_HEADER;
if (png_ptr->chunk_name != png_IDAT)
{
png_ptr->process_mode = PNG_READ_CHUNK_MODE;
if ((png_ptr->flags & PNG_FLAG_ZSTREAM_ENDED) == 0)
png_error(png_ptr, "Not enough compressed data");
return;
}
png_ptr->idat_size = png_ptr->push_length;
}
if (png_ptr->idat_size != 0 && png_ptr->save_buffer_size != 0)
{
png_size_t save_size = png_ptr->save_buffer_size;
png_uint_32 idat_size = png_ptr->idat_size;
/* We want the smaller of 'idat_size' and 'current_buffer_size', but they
* are of different types and we don't know which variable has the fewest
* bits. Carefully select the smaller and cast it to the type of the
* larger - this cannot overflow. Do not cast in the following test - it
* will break on either 16-bit or 64-bit platforms.
*/
if (idat_size < save_size)
save_size = (png_size_t)idat_size;
else
idat_size = (png_uint_32)save_size;
png_calculate_crc(png_ptr, png_ptr->save_buffer_ptr, save_size);
png_process_IDAT_data(png_ptr, png_ptr->save_buffer_ptr, save_size);
png_ptr->idat_size -= idat_size;
png_ptr->buffer_size -= save_size;
png_ptr->save_buffer_size -= save_size;
png_ptr->save_buffer_ptr += save_size;
}
if (png_ptr->idat_size != 0 && png_ptr->current_buffer_size != 0)
{
png_size_t save_size = png_ptr->current_buffer_size;
png_uint_32 idat_size = png_ptr->idat_size;
/* We want the smaller of 'idat_size' and 'current_buffer_size', but they
* are of different types and we don't know which variable has the fewest
* bits. Carefully select the smaller and cast it to the type of the
* larger - this cannot overflow.
*/
if (idat_size < save_size)
save_size = (png_size_t)idat_size;
else
idat_size = (png_uint_32)save_size;
png_calculate_crc(png_ptr, png_ptr->current_buffer_ptr, save_size);
png_process_IDAT_data(png_ptr, png_ptr->current_buffer_ptr, save_size);
png_ptr->idat_size -= idat_size;
png_ptr->buffer_size -= save_size;
png_ptr->current_buffer_size -= save_size;
png_ptr->current_buffer_ptr += save_size;
}
if (png_ptr->idat_size == 0)
{
PNG_PUSH_SAVE_BUFFER_IF_LT(4)
png_crc_finish(png_ptr, 0);
png_ptr->mode &= ~PNG_HAVE_CHUNK_HEADER;
png_ptr->mode |= PNG_AFTER_IDAT;
png_ptr->zowner = 0;
}
}
void PNGAPI
png_read_row(png_structp png_ptr, png_bytep row, png_bytep dsp_row)
{
#ifdef PNG_USE_LOCAL_ARRAYS
PNG_IDAT;
const int png_pass_dsp_mask[7] = {0xff, 0x0f, 0xff, 0x33, 0xff, 0x55, 0xff};
const int png_pass_mask[7] = {0x80, 0x08, 0x88, 0x22, 0xaa, 0x55, 0xff};
#endif
int ret;
png_debug2(1, "in png_read_row (row %lu, pass %d)\n",
png_ptr->row_number, png_ptr->pass);
if (!(png_ptr->flags & PNG_FLAG_ROW_INIT)) {
png_read_start_row(png_ptr);
}
if (png_ptr->row_number == 0 && png_ptr->pass == 0) {
/* check for transforms that have been set but were defined out */
#if defined(PNG_WRITE_INVERT_SUPPORTED) && !defined(PNG_READ_INVERT_SUPPORTED)
if (png_ptr->transformations & PNG_INVERT_MONO) {
png_warning(png_ptr, "PNG_READ_INVERT_SUPPORTED is not defined.");
}
#endif
#if defined(PNG_WRITE_FILLER_SUPPORTED) && !defined(PNG_READ_FILLER_SUPPORTED)
if (png_ptr->transformations & PNG_FILLER) {
png_warning(png_ptr, "PNG_READ_FILLER_SUPPORTED is not defined.");
}
#endif
#if defined(PNG_WRITE_PACKSWAP_SUPPORTED) && !defined(PNG_READ_PACKSWAP_SUPPORTED)
if (png_ptr->transformations & PNG_PACKSWAP) {
png_warning(png_ptr, "PNG_READ_PACKSWAP_SUPPORTED is not defined.");
}
#endif
#if defined(PNG_WRITE_PACK_SUPPORTED) && !defined(PNG_READ_PACK_SUPPORTED)
if (png_ptr->transformations & PNG_PACK) {
png_warning(png_ptr, "PNG_READ_PACK_SUPPORTED is not defined.");
}
#endif
#if defined(PNG_WRITE_SHIFT_SUPPORTED) && !defined(PNG_READ_SHIFT_SUPPORTED)
if (png_ptr->transformations & PNG_SHIFT) {
png_warning(png_ptr, "PNG_READ_SHIFT_SUPPORTED is not defined.");
}
#endif
#if defined(PNG_WRITE_BGR_SUPPORTED) && !defined(PNG_READ_BGR_SUPPORTED)
if (png_ptr->transformations & PNG_BGR) {
png_warning(png_ptr, "PNG_READ_BGR_SUPPORTED is not defined.");
}
#endif
#if defined(PNG_WRITE_SWAP_SUPPORTED) && !defined(PNG_READ_SWAP_SUPPORTED)
if (png_ptr->transformations & PNG_SWAP_BYTES) {
png_warning(png_ptr, "PNG_READ_SWAP_SUPPORTED is not defined.");
}
#endif
}
#if defined(PNG_READ_INTERLACING_SUPPORTED)
/* if interlaced and we do not need a new row, combine row and return */
if (png_ptr->interlaced && (png_ptr->transformations & PNG_INTERLACE)) {
switch (png_ptr->pass) {
case 0:
if (png_ptr->row_number & 0x07) {
if (dsp_row != NULL)
png_combine_row(png_ptr, dsp_row,
png_pass_dsp_mask[png_ptr->pass]);
png_read_finish_row(png_ptr);
return;
}
break;
case 1:
if ((png_ptr->row_number & 0x07) || png_ptr->width < 5) {
if (dsp_row != NULL)
png_combine_row(png_ptr, dsp_row,
png_pass_dsp_mask[png_ptr->pass]);
png_read_finish_row(png_ptr);
return;
}
break;
case 2:
if ((png_ptr->row_number & 0x07) != 4) {
if (dsp_row != NULL && (png_ptr->row_number & 4))
png_combine_row(png_ptr, dsp_row,
png_pass_dsp_mask[png_ptr->pass]);
png_read_finish_row(png_ptr);
return;
}
break;
case 3:
if ((png_ptr->row_number & 3) || png_ptr->width < 3) {
if (dsp_row != NULL)
png_combine_row(png_ptr, dsp_row,
png_pass_dsp_mask[png_ptr->pass]);
png_read_finish_row(png_ptr);
return;
}
break;
case 4:
if ((png_ptr->row_number & 3) != 2) {
if (dsp_row != NULL && (png_ptr->row_number & 2))
png_combine_row(png_ptr, dsp_row,
png_pass_dsp_mask[png_ptr->pass]);
png_read_finish_row(png_ptr);
return;
}
break;
case 5:
if ((png_ptr->row_number & 1) || png_ptr->width < 2) {
if (dsp_row != NULL)
png_combine_row(png_ptr, dsp_row,
png_pass_dsp_mask[png_ptr->pass]);
png_read_finish_row(png_ptr);
return;
}
break;
case 6:
if (!(png_ptr->row_number & 1)) {
png_read_finish_row(png_ptr);
return;
}
break;
}
}
#endif
if (!(png_ptr->mode & PNG_HAVE_IDAT)) {
png_error(png_ptr, "Invalid attempt to read row data");
}
png_ptr->zstream.next_out = png_ptr->row_buf;
png_ptr->zstream.avail_out = (uInt)png_ptr->irowbytes;
do {
if (!(png_ptr->zstream.avail_in)) {
while (!png_ptr->idat_size) {
png_byte chunk_length[4];
png_crc_finish(png_ptr, 0);
png_read_data(png_ptr, chunk_length, 4);
png_ptr->idat_size = png_get_uint_31(png_ptr, chunk_length);
png_reset_crc(png_ptr);
png_crc_read(png_ptr, png_ptr->chunk_name, 4);
if (png_memcmp(png_ptr->chunk_name, png_IDAT, 4)) {
png_error(png_ptr, "Not enough image data");
}
}
png_ptr->zstream.avail_in = (uInt)png_ptr->zbuf_size;
png_ptr->zstream.next_in = png_ptr->zbuf;
if (png_ptr->zbuf_size > png_ptr->idat_size) {
png_ptr->zstream.avail_in = (uInt)png_ptr->idat_size;
}
png_crc_read(png_ptr, png_ptr->zbuf,
(png_size_t)png_ptr->zstream.avail_in);
png_ptr->idat_size -= png_ptr->zstream.avail_in;
}
ret = inflate(&png_ptr->zstream, Z_PARTIAL_FLUSH);
if (ret == Z_STREAM_END) {
if (png_ptr->zstream.avail_out || png_ptr->zstream.avail_in ||
png_ptr->idat_size) {
png_error(png_ptr, "Extra compressed data");
}
png_ptr->mode |= PNG_AFTER_IDAT;
png_ptr->flags |= PNG_FLAG_ZLIB_FINISHED;
break;
}
if (ret != Z_OK)
png_error(png_ptr, png_ptr->zstream.msg ? png_ptr->zstream.msg :
"Decompression error");
} while (png_ptr->zstream.avail_out);
png_ptr->row_info.color_type = png_ptr->color_type;
png_ptr->row_info.width = png_ptr->iwidth;
png_ptr->row_info.channels = png_ptr->channels;
png_ptr->row_info.bit_depth = png_ptr->bit_depth;
png_ptr->row_info.pixel_depth = png_ptr->pixel_depth;
png_ptr->row_info.rowbytes = PNG_ROWBYTES(png_ptr->row_info.pixel_depth,
png_ptr->row_info.width);
if (png_ptr->row_buf[0])
png_read_filter_row(png_ptr, &(png_ptr->row_info),
png_ptr->row_buf + 1, png_ptr->prev_row + 1,
(int)(png_ptr->row_buf[0]));
png_memcpy_check(png_ptr, png_ptr->prev_row, png_ptr->row_buf,
png_ptr->rowbytes + 1);
#if defined(PNG_MNG_FEATURES_SUPPORTED)
if ((png_ptr->mng_features_permitted & PNG_FLAG_MNG_FILTER_64) &&
(png_ptr->filter_type == PNG_INTRAPIXEL_DIFFERENCING)) {
/* Intrapixel differencing */
png_do_read_intrapixel(&(png_ptr->row_info), png_ptr->row_buf + 1);
}
#endif
if (png_ptr->transformations || (png_ptr->flags & PNG_FLAG_STRIP_ALPHA)) {
png_do_read_transformations(png_ptr);
}
#if defined(PNG_READ_INTERLACING_SUPPORTED)
/* blow up interlaced rows to full size */
if (png_ptr->interlaced &&
(png_ptr->transformations & PNG_INTERLACE)) {
if (png_ptr->pass < 6)
/* old interface (pre-1.0.9):
png_do_read_interlace(&(png_ptr->row_info),
png_ptr->row_buf + 1, png_ptr->pass, png_ptr->transformations);
*/
{
png_do_read_interlace(png_ptr);
}
if (dsp_row != NULL)
png_combine_row(png_ptr, dsp_row,
png_pass_dsp_mask[png_ptr->pass]);
if (row != NULL)
png_combine_row(png_ptr, row,
png_pass_mask[png_ptr->pass]);
} else
#endif
{
if (row != NULL) {
png_combine_row(png_ptr, row, 0xff);
}
if (dsp_row != NULL) {
png_combine_row(png_ptr, dsp_row, 0xff);
}
}
png_read_finish_row(png_ptr);
if (png_ptr->read_row_fn != NULL) {
(*(png_ptr->read_row_fn))(png_ptr, png_ptr->row_number, png_ptr->pass);
}
}
/* Read the information before the actual image data. This has been
* changed in v0.90 to allow reading a file that already has the magic
* bytes read from the stream. You can tell libpng how many bytes have
* been read from the beginning of the stream (up to the maximum of 8)
* via png_set_sig_bytes(), and we will only check the remaining bytes
* here. The application can then have access to the signature bytes we
* read if it is determined that this isn't a valid PNG file.
*/
void PNGAPI
png_read_info(png_structp png_ptr, png_infop info_ptr)
{
png_debug(1, "in png_read_info\n");
/* If we haven't checked all of the PNG signature bytes, do so now. */
if (png_ptr->sig_bytes < 8) {
png_size_t num_checked = png_ptr->sig_bytes,
num_to_check = 8 - num_checked;
png_read_data(png_ptr, &(info_ptr->signature[num_checked]), num_to_check);
png_ptr->sig_bytes = 8;
if (png_sig_cmp(info_ptr->signature, num_checked, num_to_check)) {
if (num_checked < 4 &&
png_sig_cmp(info_ptr->signature, num_checked, num_to_check - 4)) {
png_error(png_ptr, "Not a PNG file");
} else {
png_error(png_ptr, "PNG file corrupted by ASCII conversion");
}
}
if (num_checked < 3) {
png_ptr->mode |= PNG_HAVE_PNG_SIGNATURE;
}
}
for (;;) {
#ifdef PNG_USE_LOCAL_ARRAYS
PNG_IHDR;
PNG_IDAT;
PNG_IEND;
PNG_PLTE;
#if defined(PNG_READ_bKGD_SUPPORTED)
PNG_bKGD;
#endif
#if defined(PNG_READ_cHRM_SUPPORTED)
PNG_cHRM;
#endif
#if defined(PNG_READ_gAMA_SUPPORTED)
PNG_gAMA;
#endif
#if defined(PNG_READ_hIST_SUPPORTED)
PNG_hIST;
#endif
#if defined(PNG_READ_iCCP_SUPPORTED)
PNG_iCCP;
#endif
#if defined(PNG_READ_iTXt_SUPPORTED)
PNG_iTXt;
#endif
#if defined(PNG_READ_oFFs_SUPPORTED)
PNG_oFFs;
#endif
#if defined(PNG_READ_pCAL_SUPPORTED)
PNG_pCAL;
#endif
#if defined(PNG_READ_pHYs_SUPPORTED)
PNG_pHYs;
#endif
#if defined(PNG_READ_sBIT_SUPPORTED)
PNG_sBIT;
#endif
#if defined(PNG_READ_sCAL_SUPPORTED)
PNG_sCAL;
#endif
#if defined(PNG_READ_sPLT_SUPPORTED)
PNG_sPLT;
#endif
#if defined(PNG_READ_sRGB_SUPPORTED)
PNG_sRGB;
#endif
#if defined(PNG_READ_tEXt_SUPPORTED)
PNG_tEXt;
#endif
#if defined(PNG_READ_tIME_SUPPORTED)
PNG_tIME;
#endif
#if defined(PNG_READ_tRNS_SUPPORTED)
PNG_tRNS;
#endif
#if defined(PNG_READ_zTXt_SUPPORTED)
PNG_zTXt;
#endif
#endif /* PNG_USE_LOCAL_ARRAYS */
png_byte chunk_length[4];
png_uint_32 length;
png_read_data(png_ptr, chunk_length, 4);
length = png_get_uint_31(png_ptr, chunk_length);
png_reset_crc(png_ptr);
png_crc_read(png_ptr, png_ptr->chunk_name, 4);
png_debug2(0, "Reading %s chunk, length=%lu.\n", png_ptr->chunk_name,
length);
/* This should be a binary subdivision search or a hash for
* matching the chunk name rather than a linear search.
*/
if (!png_memcmp(png_ptr->chunk_name, png_IHDR, 4)) {
png_handle_IHDR(png_ptr, info_ptr, length);
} else if (!png_memcmp(png_ptr->chunk_name, png_IEND, 4)) {
png_handle_IEND(png_ptr, info_ptr, length);
}
#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
else if (png_handle_as_unknown(png_ptr, png_ptr->chunk_name)) {
if (!png_memcmp(png_ptr->chunk_name, png_IDAT, 4)) {
png_ptr->mode |= PNG_HAVE_IDAT;
}
png_handle_unknown(png_ptr, info_ptr, length);
if (!png_memcmp(png_ptr->chunk_name, png_PLTE, 4)) {
png_ptr->mode |= PNG_HAVE_PLTE;
} else if (!png_memcmp(png_ptr->chunk_name, png_IDAT, 4)) {
if (!(png_ptr->mode & PNG_HAVE_IHDR)) {
png_error(png_ptr, "Missing IHDR before IDAT");
} else if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE &&
!(png_ptr->mode & PNG_HAVE_PLTE)) {
png_error(png_ptr, "Missing PLTE before IDAT");
}
break;
}
}
#endif
else if (!png_memcmp(png_ptr->chunk_name, png_PLTE, 4)) {
png_handle_PLTE(png_ptr, info_ptr, length);
} else if (!png_memcmp(png_ptr->chunk_name, png_IDAT, 4)) {
if (!(png_ptr->mode & PNG_HAVE_IHDR)) {
png_error(png_ptr, "Missing IHDR before IDAT");
} else if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE &&
!(png_ptr->mode & PNG_HAVE_PLTE)) {
png_error(png_ptr, "Missing PLTE before IDAT");
}
png_ptr->idat_size = length;
png_ptr->mode |= PNG_HAVE_IDAT;
break;
}
#if defined(PNG_READ_bKGD_SUPPORTED)
else if (!png_memcmp(png_ptr->chunk_name, png_bKGD, 4)) {
png_handle_bKGD(png_ptr, info_ptr, length);
}
#endif
#if defined(PNG_READ_cHRM_SUPPORTED)
else if (!png_memcmp(png_ptr->chunk_name, png_cHRM, 4)) {
png_handle_cHRM(png_ptr, info_ptr, length);
}
#endif
#if defined(PNG_READ_gAMA_SUPPORTED)
else if (!png_memcmp(png_ptr->chunk_name, png_gAMA, 4)) {
png_handle_gAMA(png_ptr, info_ptr, length);
}
#endif
#if defined(PNG_READ_hIST_SUPPORTED)
else if (!png_memcmp(png_ptr->chunk_name, png_hIST, 4)) {
png_handle_hIST(png_ptr, info_ptr, length);
}
#endif
#if defined(PNG_READ_oFFs_SUPPORTED)
else if (!png_memcmp(png_ptr->chunk_name, png_oFFs, 4)) {
png_handle_oFFs(png_ptr, info_ptr, length);
}
#endif
#if defined(PNG_READ_pCAL_SUPPORTED)
else if (!png_memcmp(png_ptr->chunk_name, png_pCAL, 4)) {
png_handle_pCAL(png_ptr, info_ptr, length);
}
#endif
#if defined(PNG_READ_sCAL_SUPPORTED)
else if (!png_memcmp(png_ptr->chunk_name, png_sCAL, 4)) {
png_handle_sCAL(png_ptr, info_ptr, length);
}
#endif
#if defined(PNG_READ_pHYs_SUPPORTED)
else if (!png_memcmp(png_ptr->chunk_name, png_pHYs, 4)) {
png_handle_pHYs(png_ptr, info_ptr, length);
}
#endif
#if defined(PNG_READ_sBIT_SUPPORTED)
else if (!png_memcmp(png_ptr->chunk_name, png_sBIT, 4)) {
png_handle_sBIT(png_ptr, info_ptr, length);
}
#endif
#if defined(PNG_READ_sRGB_SUPPORTED)
else if (!png_memcmp(png_ptr->chunk_name, png_sRGB, 4)) {
png_handle_sRGB(png_ptr, info_ptr, length);
}
#endif
#if defined(PNG_READ_iCCP_SUPPORTED)
else if (!png_memcmp(png_ptr->chunk_name, png_iCCP, 4)) {
png_handle_iCCP(png_ptr, info_ptr, length);
}
#endif
#if defined(PNG_READ_sPLT_SUPPORTED)
else if (!png_memcmp(png_ptr->chunk_name, png_sPLT, 4)) {
png_handle_sPLT(png_ptr, info_ptr, length);
}
#endif
#if defined(PNG_READ_tEXt_SUPPORTED)
else if (!png_memcmp(png_ptr->chunk_name, png_tEXt, 4)) {
png_handle_tEXt(png_ptr, info_ptr, length);
}
#endif
#if defined(PNG_READ_tIME_SUPPORTED)
else if (!png_memcmp(png_ptr->chunk_name, png_tIME, 4)) {
png_handle_tIME(png_ptr, info_ptr, length);
}
#endif
#if defined(PNG_READ_tRNS_SUPPORTED)
else if (!png_memcmp(png_ptr->chunk_name, png_tRNS, 4)) {
png_handle_tRNS(png_ptr, info_ptr, length);
}
#endif
#if defined(PNG_READ_zTXt_SUPPORTED)
else if (!png_memcmp(png_ptr->chunk_name, png_zTXt, 4)) {
png_handle_zTXt(png_ptr, info_ptr, length);
}
#endif
#if defined(PNG_READ_iTXt_SUPPORTED)
else if (!png_memcmp(png_ptr->chunk_name, png_iTXt, 4)) {
png_handle_iTXt(png_ptr, info_ptr, length);
}
#endif
else {
png_handle_unknown(png_ptr, info_ptr, length);
}
}
}
/* Read the end of the PNG file. Will not read past the end of the
* file, will verify the end is accurate, and will read any comments
* or time information at the end of the file, if info is not NULL.
*/
void PNGAPI
png_read_end(png_structp png_ptr, png_infop info_ptr)
{
png_byte chunk_length[4];
png_uint_32 length;
png_debug(1, "in png_read_end\n");
png_crc_finish(png_ptr, 0); /* Finish off CRC from last IDAT chunk */
do {
#ifdef PNG_USE_LOCAL_ARRAYS
PNG_IHDR;
PNG_IDAT;
PNG_IEND;
PNG_PLTE;
#if defined(PNG_READ_bKGD_SUPPORTED)
PNG_bKGD;
#endif
#if defined(PNG_READ_cHRM_SUPPORTED)
PNG_cHRM;
#endif
#if defined(PNG_READ_gAMA_SUPPORTED)
PNG_gAMA;
#endif
#if defined(PNG_READ_hIST_SUPPORTED)
PNG_hIST;
#endif
#if defined(PNG_READ_iCCP_SUPPORTED)
PNG_iCCP;
#endif
#if defined(PNG_READ_iTXt_SUPPORTED)
PNG_iTXt;
#endif
#if defined(PNG_READ_oFFs_SUPPORTED)
PNG_oFFs;
#endif
#if defined(PNG_READ_pCAL_SUPPORTED)
PNG_pCAL;
#endif
#if defined(PNG_READ_pHYs_SUPPORTED)
PNG_pHYs;
#endif
#if defined(PNG_READ_sBIT_SUPPORTED)
PNG_sBIT;
#endif
#if defined(PNG_READ_sCAL_SUPPORTED)
PNG_sCAL;
#endif
#if defined(PNG_READ_sPLT_SUPPORTED)
PNG_sPLT;
#endif
#if defined(PNG_READ_sRGB_SUPPORTED)
PNG_sRGB;
#endif
#if defined(PNG_READ_tEXt_SUPPORTED)
PNG_tEXt;
#endif
#if defined(PNG_READ_tIME_SUPPORTED)
PNG_tIME;
#endif
#if defined(PNG_READ_tRNS_SUPPORTED)
PNG_tRNS;
#endif
#if defined(PNG_READ_zTXt_SUPPORTED)
PNG_zTXt;
#endif
#endif /* PNG_USE_LOCAL_ARRAYS */
png_read_data(png_ptr, chunk_length, 4);
length = png_get_uint_31(png_ptr, chunk_length);
png_reset_crc(png_ptr);
png_crc_read(png_ptr, png_ptr->chunk_name, 4);
png_debug1(0, "Reading %s chunk.\n", png_ptr->chunk_name);
if (!png_memcmp(png_ptr->chunk_name, png_IHDR, 4)) {
png_handle_IHDR(png_ptr, info_ptr, length);
} else if (!png_memcmp(png_ptr->chunk_name, png_IEND, 4)) {
png_handle_IEND(png_ptr, info_ptr, length);
}
#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
else if (png_handle_as_unknown(png_ptr, png_ptr->chunk_name)) {
if (!png_memcmp(png_ptr->chunk_name, png_IDAT, 4)) {
if (length > 0 || png_ptr->mode & PNG_AFTER_IDAT) {
png_error(png_ptr, "Too many IDAT's found");
}
} else {
png_ptr->mode |= PNG_AFTER_IDAT;
}
png_handle_unknown(png_ptr, info_ptr, length);
if (!png_memcmp(png_ptr->chunk_name, png_PLTE, 4)) {
png_ptr->mode |= PNG_HAVE_PLTE;
}
}
#endif
else if (!png_memcmp(png_ptr->chunk_name, png_IDAT, 4)) {
/* Zero length IDATs are legal after the last IDAT has been
* read, but not after other chunks have been read.
*/
if (length > 0 || png_ptr->mode & PNG_AFTER_IDAT) {
png_error(png_ptr, "Too many IDAT's found");
}
png_crc_finish(png_ptr, length);
} else if (!png_memcmp(png_ptr->chunk_name, png_PLTE, 4)) {
png_handle_PLTE(png_ptr, info_ptr, length);
}
#if defined(PNG_READ_bKGD_SUPPORTED)
else if (!png_memcmp(png_ptr->chunk_name, png_bKGD, 4)) {
png_handle_bKGD(png_ptr, info_ptr, length);
}
#endif
#if defined(PNG_READ_cHRM_SUPPORTED)
else if (!png_memcmp(png_ptr->chunk_name, png_cHRM, 4)) {
png_handle_cHRM(png_ptr, info_ptr, length);
}
#endif
#if defined(PNG_READ_gAMA_SUPPORTED)
else if (!png_memcmp(png_ptr->chunk_name, png_gAMA, 4)) {
png_handle_gAMA(png_ptr, info_ptr, length);
}
#endif
#if defined(PNG_READ_hIST_SUPPORTED)
else if (!png_memcmp(png_ptr->chunk_name, png_hIST, 4)) {
png_handle_hIST(png_ptr, info_ptr, length);
}
#endif
#if defined(PNG_READ_oFFs_SUPPORTED)
else if (!png_memcmp(png_ptr->chunk_name, png_oFFs, 4)) {
png_handle_oFFs(png_ptr, info_ptr, length);
}
#endif
#if defined(PNG_READ_pCAL_SUPPORTED)
else if (!png_memcmp(png_ptr->chunk_name, png_pCAL, 4)) {
png_handle_pCAL(png_ptr, info_ptr, length);
}
#endif
#if defined(PNG_READ_sCAL_SUPPORTED)
else if (!png_memcmp(png_ptr->chunk_name, png_sCAL, 4)) {
png_handle_sCAL(png_ptr, info_ptr, length);
}
#endif
#if defined(PNG_READ_pHYs_SUPPORTED)
else if (!png_memcmp(png_ptr->chunk_name, png_pHYs, 4)) {
png_handle_pHYs(png_ptr, info_ptr, length);
}
#endif
#if defined(PNG_READ_sBIT_SUPPORTED)
else if (!png_memcmp(png_ptr->chunk_name, png_sBIT, 4)) {
png_handle_sBIT(png_ptr, info_ptr, length);
}
#endif
#if defined(PNG_READ_sRGB_SUPPORTED)
else if (!png_memcmp(png_ptr->chunk_name, png_sRGB, 4)) {
png_handle_sRGB(png_ptr, info_ptr, length);
}
#endif
#if defined(PNG_READ_iCCP_SUPPORTED)
else if (!png_memcmp(png_ptr->chunk_name, png_iCCP, 4)) {
png_handle_iCCP(png_ptr, info_ptr, length);
}
#endif
#if defined(PNG_READ_sPLT_SUPPORTED)
else if (!png_memcmp(png_ptr->chunk_name, png_sPLT, 4)) {
png_handle_sPLT(png_ptr, info_ptr, length);
}
#endif
#if defined(PNG_READ_tEXt_SUPPORTED)
else if (!png_memcmp(png_ptr->chunk_name, png_tEXt, 4)) {
png_handle_tEXt(png_ptr, info_ptr, length);
}
#endif
#if defined(PNG_READ_tIME_SUPPORTED)
else if (!png_memcmp(png_ptr->chunk_name, png_tIME, 4)) {
png_handle_tIME(png_ptr, info_ptr, length);
}
#endif
#if defined(PNG_READ_tRNS_SUPPORTED)
else if (!png_memcmp(png_ptr->chunk_name, png_tRNS, 4)) {
png_handle_tRNS(png_ptr, info_ptr, length);
}
#endif
#if defined(PNG_READ_zTXt_SUPPORTED)
else if (!png_memcmp(png_ptr->chunk_name, png_zTXt, 4)) {
png_handle_zTXt(png_ptr, info_ptr, length);
}
#endif
#if defined(PNG_READ_iTXt_SUPPORTED)
else if (!png_memcmp(png_ptr->chunk_name, png_iTXt, 4)) {
png_handle_iTXt(png_ptr, info_ptr, length);
}
#endif
else {
png_handle_unknown(png_ptr, info_ptr, length);
}
} while (!(png_ptr->mode & PNG_HAVE_IEND));
}
void /* PRIVATE */
png_push_read_chunk(png_structp png_ptr, png_infop info_ptr)
{
png_uint_32 chunk_name;
/* First we make sure we have enough data for the 4 byte chunk name
* and the 4 byte chunk length before proceeding with decoding the
* chunk data. To fully decode each of these chunks, we also make
* sure we have enough data in the buffer for the 4 byte CRC at the
* end of every chunk (except IDAT, which is handled separately).
*/
if (!(png_ptr->mode & PNG_HAVE_CHUNK_HEADER))
{
png_byte chunk_length[4];
png_byte chunk_tag[4];
if (png_ptr->buffer_size < 8)
{
png_push_save_buffer(png_ptr);
return;
}
png_push_fill_buffer(png_ptr, chunk_length, 4);
png_ptr->push_length = png_get_uint_31(png_ptr, chunk_length);
png_reset_crc(png_ptr);
png_crc_read(png_ptr, chunk_tag, 4);
png_ptr->chunk_name = PNG_CHUNK_FROM_STRING(chunk_tag);
png_check_chunk_name(png_ptr, png_ptr->chunk_name);
png_ptr->mode |= PNG_HAVE_CHUNK_HEADER;
}
chunk_name = png_ptr->chunk_name;
if (chunk_name == png_IDAT)
{
/* This is here above the if/else case statement below because if the
* unknown handling marks 'IDAT' as unknown then the IDAT handling case is
* completely skipped.
*
* TODO: there must be a better way of doing this.
*/
if (png_ptr->mode & PNG_AFTER_IDAT)
png_ptr->mode |= PNG_HAVE_CHUNK_AFTER_IDAT;
}
if (chunk_name == png_IHDR)
{
if (png_ptr->push_length != 13)
png_error(png_ptr, "Invalid IHDR length");
if (png_ptr->push_length + 4 > png_ptr->buffer_size)
{
png_push_save_buffer(png_ptr);
return;
}
png_handle_IHDR(png_ptr, info_ptr, png_ptr->push_length);
}
else if (chunk_name == png_IEND)
{
if (png_ptr->push_length + 4 > png_ptr->buffer_size)
{
png_push_save_buffer(png_ptr);
return;
}
png_handle_IEND(png_ptr, info_ptr, png_ptr->push_length);
png_ptr->process_mode = PNG_READ_DONE_MODE;
png_push_have_end(png_ptr, info_ptr);
}
#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
else if (png_chunk_unknown_handling(png_ptr, chunk_name))
{
if (png_ptr->push_length + 4 > png_ptr->buffer_size)
{
png_push_save_buffer(png_ptr);
return;
}
if (chunk_name == png_IDAT)
png_ptr->mode |= PNG_HAVE_IDAT;
png_handle_unknown(png_ptr, info_ptr, png_ptr->push_length);
if (chunk_name == png_PLTE)
png_ptr->mode |= PNG_HAVE_PLTE;
else if (chunk_name == png_IDAT)
{
if (!(png_ptr->mode & PNG_HAVE_IHDR))
png_error(png_ptr, "Missing IHDR before IDAT");
else if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE &&
!(png_ptr->mode & PNG_HAVE_PLTE))
png_error(png_ptr, "Missing PLTE before IDAT");
}
}
#endif
else if (chunk_name == png_PLTE)
{
if (png_ptr->push_length + 4 > png_ptr->buffer_size)
{
png_push_save_buffer(png_ptr);
return;
}
png_handle_PLTE(png_ptr, info_ptr, png_ptr->push_length);
}
else if (chunk_name == png_IDAT)
{
/* If we reach an IDAT chunk, this means we have read all of the
* header chunks, and we can start reading the image (or if this
* is called after the image has been read - we have an error).
*/
if (!(png_ptr->mode & PNG_HAVE_IHDR))
png_error(png_ptr, "Missing IHDR before IDAT");
else if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE &&
!(png_ptr->mode & PNG_HAVE_PLTE))
png_error(png_ptr, "Missing PLTE before IDAT");
if (png_ptr->mode & PNG_HAVE_IDAT)
{
if (!(png_ptr->mode & PNG_HAVE_CHUNK_AFTER_IDAT))
if (png_ptr->push_length == 0)
return;
if (png_ptr->mode & PNG_AFTER_IDAT)
png_benign_error(png_ptr, "Too many IDATs found");
}
png_ptr->idat_size = png_ptr->push_length;
png_ptr->mode |= PNG_HAVE_IDAT;
png_ptr->process_mode = PNG_READ_IDAT_MODE;
png_push_have_info(png_ptr, info_ptr);
png_ptr->zstream.avail_out =
(uInt) PNG_ROWBYTES(png_ptr->pixel_depth,
png_ptr->iwidth) + 1;
png_ptr->zstream.next_out = png_ptr->row_buf;
return;
}
#ifdef PNG_READ_gAMA_SUPPORTED
else if (png_ptr->chunk_name == png_gAMA)
{
if (png_ptr->push_length + 4 > png_ptr->buffer_size)
{
png_push_save_buffer(png_ptr);
return;
}
png_handle_gAMA(png_ptr, info_ptr, png_ptr->push_length);
}
#endif
#ifdef PNG_READ_sBIT_SUPPORTED
else if (png_ptr->chunk_name == png_sBIT)
{
if (png_ptr->push_length + 4 > png_ptr->buffer_size)
{
png_push_save_buffer(png_ptr);
return;
}
png_handle_sBIT(png_ptr, info_ptr, png_ptr->push_length);
}
#endif
#ifdef PNG_READ_cHRM_SUPPORTED
else if (png_ptr->chunk_name == png_cHRM)
{
if (png_ptr->push_length + 4 > png_ptr->buffer_size)
{
png_push_save_buffer(png_ptr);
return;
}
png_handle_cHRM(png_ptr, info_ptr, png_ptr->push_length);
}
#endif
#ifdef PNG_READ_sRGB_SUPPORTED
else if (chunk_name == png_sRGB)
{
if (png_ptr->push_length + 4 > png_ptr->buffer_size)
{
png_push_save_buffer(png_ptr);
return;
}
png_handle_sRGB(png_ptr, info_ptr, png_ptr->push_length);
}
#endif
#ifdef PNG_READ_iCCP_SUPPORTED
else if (png_ptr->chunk_name == png_iCCP)
{
if (png_ptr->push_length + 4 > png_ptr->buffer_size)
{
png_push_save_buffer(png_ptr);
return;
}
png_handle_iCCP(png_ptr, info_ptr, png_ptr->push_length);
}
#endif
#ifdef PNG_READ_sPLT_SUPPORTED
else if (chunk_name == png_sPLT)
{
if (png_ptr->push_length + 4 > png_ptr->buffer_size)
{
png_push_save_buffer(png_ptr);
return;
}
png_handle_sPLT(png_ptr, info_ptr, png_ptr->push_length);
}
#endif
#ifdef PNG_READ_tRNS_SUPPORTED
else if (chunk_name == png_tRNS)
{
if (png_ptr->push_length + 4 > png_ptr->buffer_size)
{
png_push_save_buffer(png_ptr);
return;
}
png_handle_tRNS(png_ptr, info_ptr, png_ptr->push_length);
}
#endif
#ifdef PNG_READ_bKGD_SUPPORTED
else if (chunk_name == png_bKGD)
{
if (png_ptr->push_length + 4 > png_ptr->buffer_size)
{
png_push_save_buffer(png_ptr);
return;
}
png_handle_bKGD(png_ptr, info_ptr, png_ptr->push_length);
}
#endif
#ifdef PNG_READ_hIST_SUPPORTED
else if (chunk_name == png_hIST)
{
if (png_ptr->push_length + 4 > png_ptr->buffer_size)
{
png_push_save_buffer(png_ptr);
return;
}
png_handle_hIST(png_ptr, info_ptr, png_ptr->push_length);
}
#endif
#ifdef PNG_READ_pHYs_SUPPORTED
else if (chunk_name == png_pHYs)
{
if (png_ptr->push_length + 4 > png_ptr->buffer_size)
{
png_push_save_buffer(png_ptr);
return;
}
png_handle_pHYs(png_ptr, info_ptr, png_ptr->push_length);
}
#endif
#ifdef PNG_READ_oFFs_SUPPORTED
else if (chunk_name == png_oFFs)
{
if (png_ptr->push_length + 4 > png_ptr->buffer_size)
{
png_push_save_buffer(png_ptr);
return;
}
png_handle_oFFs(png_ptr, info_ptr, png_ptr->push_length);
}
#endif
#ifdef PNG_READ_pCAL_SUPPORTED
else if (chunk_name == png_pCAL)
{
if (png_ptr->push_length + 4 > png_ptr->buffer_size)
{
png_push_save_buffer(png_ptr);
return;
}
png_handle_pCAL(png_ptr, info_ptr, png_ptr->push_length);
}
#endif
#ifdef PNG_READ_sCAL_SUPPORTED
else if (chunk_name == png_sCAL)
{
if (png_ptr->push_length + 4 > png_ptr->buffer_size)
{
png_push_save_buffer(png_ptr);
return;
}
png_handle_sCAL(png_ptr, info_ptr, png_ptr->push_length);
}
#endif
#ifdef PNG_READ_tIME_SUPPORTED
else if (chunk_name == png_tIME)
{
if (png_ptr->push_length + 4 > png_ptr->buffer_size)
{
png_push_save_buffer(png_ptr);
return;
}
png_handle_tIME(png_ptr, info_ptr, png_ptr->push_length);
}
#endif
#ifdef PNG_READ_tEXt_SUPPORTED
else if (chunk_name == png_tEXt)
{
if (png_ptr->push_length + 4 > png_ptr->buffer_size)
{
png_push_save_buffer(png_ptr);
return;
}
png_handle_tEXt(png_ptr, info_ptr, png_ptr->push_length);
}
#endif
#ifdef PNG_READ_zTXt_SUPPORTED
else if (chunk_name == png_zTXt)
{
if (png_ptr->push_length + 4 > png_ptr->buffer_size)
{
png_push_save_buffer(png_ptr);
return;
}
png_handle_zTXt(png_ptr, info_ptr, png_ptr->push_length);
}
#endif
#ifdef PNG_READ_iTXt_SUPPORTED
else if (chunk_name == png_iTXt)
{
if (png_ptr->push_length + 4 > png_ptr->buffer_size)
{
png_push_save_buffer(png_ptr);
return;
}
png_handle_iTXt(png_ptr, info_ptr, png_ptr->push_length);
}
#endif
else
{
if (png_ptr->push_length + 4 > png_ptr->buffer_size)
{
png_push_save_buffer(png_ptr);
return;
}
png_handle_unknown(png_ptr, info_ptr, png_ptr->push_length);
}
png_ptr->mode &= ~PNG_HAVE_CHUNK_HEADER;
}
void PNGAPI
png_read_end(png_structp png_ptr, png_infop info_ptr)
{
png_byte chunk_length[4];
png_uint_32 length;
png_debug(1, "in png_read_end\n");
if(png_ptr == NULL) return;
png_crc_finish(png_ptr, 0);
do
{
#ifdef PNG_USE_LOCAL_ARRAYS
PNG_CONST PNG_IHDR;
PNG_CONST PNG_IDAT;
PNG_CONST PNG_IEND;
PNG_CONST PNG_PLTE;
#if defined(PNG_READ_bKGD_SUPPORTED)
PNG_CONST PNG_bKGD;
#endif
#if defined(PNG_READ_cHRM_SUPPORTED)
PNG_CONST PNG_cHRM;
#endif
#if defined(PNG_READ_gAMA_SUPPORTED)
PNG_CONST PNG_gAMA;
#endif
#if defined(PNG_READ_hIST_SUPPORTED)
PNG_CONST PNG_hIST;
#endif
#if defined(PNG_READ_iCCP_SUPPORTED)
PNG_CONST PNG_iCCP;
#endif
#if defined(PNG_READ_iTXt_SUPPORTED)
PNG_CONST PNG_iTXt;
#endif
#if defined(PNG_READ_oFFs_SUPPORTED)
PNG_CONST PNG_oFFs;
#endif
#if defined(PNG_READ_pCAL_SUPPORTED)
PNG_CONST PNG_pCAL;
#endif
#if defined(PNG_READ_pHYs_SUPPORTED)
PNG_CONST PNG_pHYs;
#endif
#if defined(PNG_READ_sBIT_SUPPORTED)
PNG_CONST PNG_sBIT;
#endif
#if defined(PNG_READ_sCAL_SUPPORTED)
PNG_CONST PNG_sCAL;
#endif
#if defined(PNG_READ_sPLT_SUPPORTED)
PNG_CONST PNG_sPLT;
#endif
#if defined(PNG_READ_sRGB_SUPPORTED)
PNG_CONST PNG_sRGB;
#endif
#if defined(PNG_READ_tEXt_SUPPORTED)
PNG_CONST PNG_tEXt;
#endif
#if defined(PNG_READ_tIME_SUPPORTED)
PNG_CONST PNG_tIME;
#endif
#if defined(PNG_READ_tRNS_SUPPORTED)
PNG_CONST PNG_tRNS;
#endif
#if defined(PNG_READ_zTXt_SUPPORTED)
PNG_CONST PNG_zTXt;
#endif
#endif
png_read_data(png_ptr, chunk_length, 4);
length = png_get_uint_31(png_ptr,chunk_length);
png_reset_crc(png_ptr);
png_crc_read(png_ptr, png_ptr->chunk_name, 4);
png_debug1(0, "Reading %s chunk.\n", png_ptr->chunk_name);
if (!png_memcmp(png_ptr->chunk_name, png_IHDR, 4))
png_handle_IHDR(png_ptr, info_ptr, length);
else if (!png_memcmp(png_ptr->chunk_name, png_IEND, 4))
png_handle_IEND(png_ptr, info_ptr, length);
#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
else if (png_handle_as_unknown(png_ptr, png_ptr->chunk_name))
{
if (!png_memcmp(png_ptr->chunk_name, png_IDAT, 4))
{
if ((length > 0) || (png_ptr->mode & PNG_HAVE_CHUNK_AFTER_IDAT))
png_error(png_ptr, "Too many IDAT's found");
}
png_handle_unknown(png_ptr, info_ptr, length);
if (!png_memcmp(png_ptr->chunk_name, png_PLTE, 4))
png_ptr->mode |= PNG_HAVE_PLTE;
}
#endif
else if (!png_memcmp(png_ptr->chunk_name, png_IDAT, 4))
{
if ((length > 0) || (png_ptr->mode & PNG_HAVE_CHUNK_AFTER_IDAT))
png_error(png_ptr, "Too many IDAT's found");
png_crc_finish(png_ptr, length);
}
else if (!png_memcmp(png_ptr->chunk_name, png_PLTE, 4))
png_handle_PLTE(png_ptr, info_ptr, length);
#if defined(PNG_READ_bKGD_SUPPORTED)
else if (!png_memcmp(png_ptr->chunk_name, png_bKGD, 4))
png_handle_bKGD(png_ptr, info_ptr, length);
#endif
#if defined(PNG_READ_cHRM_SUPPORTED)
else if (!png_memcmp(png_ptr->chunk_name, png_cHRM, 4))
png_handle_cHRM(png_ptr, info_ptr, length);
#endif
#if defined(PNG_READ_gAMA_SUPPORTED)
else if (!png_memcmp(png_ptr->chunk_name, png_gAMA, 4))
png_handle_gAMA(png_ptr, info_ptr, length);
#endif
#if defined(PNG_READ_hIST_SUPPORTED)
else if (!png_memcmp(png_ptr->chunk_name, png_hIST, 4))
png_handle_hIST(png_ptr, info_ptr, length);
#endif
#if defined(PNG_READ_oFFs_SUPPORTED)
else if (!png_memcmp(png_ptr->chunk_name, png_oFFs, 4))
png_handle_oFFs(png_ptr, info_ptr, length);
#endif
#if defined(PNG_READ_pCAL_SUPPORTED)
else if (!png_memcmp(png_ptr->chunk_name, png_pCAL, 4))
png_handle_pCAL(png_ptr, info_ptr, length);
#endif
#if defined(PNG_READ_sCAL_SUPPORTED)
else if (!png_memcmp(png_ptr->chunk_name, png_sCAL, 4))
png_handle_sCAL(png_ptr, info_ptr, length);
#endif
#if defined(PNG_READ_pHYs_SUPPORTED)
else if (!png_memcmp(png_ptr->chunk_name, png_pHYs, 4))
png_handle_pHYs(png_ptr, info_ptr, length);
#endif
#if defined(PNG_READ_sBIT_SUPPORTED)
else if (!png_memcmp(png_ptr->chunk_name, png_sBIT, 4))
png_handle_sBIT(png_ptr, info_ptr, length);
#endif
#if defined(PNG_READ_sRGB_SUPPORTED)
else if (!png_memcmp(png_ptr->chunk_name, png_sRGB, 4))
png_handle_sRGB(png_ptr, info_ptr, length);
#endif
#if defined(PNG_READ_iCCP_SUPPORTED)
else if (!png_memcmp(png_ptr->chunk_name, png_iCCP, 4))
png_handle_iCCP(png_ptr, info_ptr, length);
#endif
#if defined(PNG_READ_sPLT_SUPPORTED)
else if (!png_memcmp(png_ptr->chunk_name, png_sPLT, 4))
png_handle_sPLT(png_ptr, info_ptr, length);
#endif
#if defined(PNG_READ_tEXt_SUPPORTED)
else if (!png_memcmp(png_ptr->chunk_name, png_tEXt, 4))
png_handle_tEXt(png_ptr, info_ptr, length);
#endif
#if defined(PNG_READ_tIME_SUPPORTED)
else if (!png_memcmp(png_ptr->chunk_name, png_tIME, 4))
png_handle_tIME(png_ptr, info_ptr, length);
#endif
#if defined(PNG_READ_tRNS_SUPPORTED)
else if (!png_memcmp(png_ptr->chunk_name, png_tRNS, 4))
png_handle_tRNS(png_ptr, info_ptr, length);
#endif
#if defined(PNG_READ_zTXt_SUPPORTED)
else if (!png_memcmp(png_ptr->chunk_name, png_zTXt, 4))
png_handle_zTXt(png_ptr, info_ptr, length);
#endif
#if defined(PNG_READ_iTXt_SUPPORTED)
else if (!png_memcmp(png_ptr->chunk_name, png_iTXt, 4))
png_handle_iTXt(png_ptr, info_ptr, length);
#endif
else
png_handle_unknown(png_ptr, info_ptr, length);
} while (!(png_ptr->mode & PNG_HAVE_IEND));
}
