void PNGAPI
png_read_png(png_structp png_ptr, png_infop info_ptr,
int transforms,
voidp params)
{
int row;
if (png_ptr == NULL)
return;
/* png_read_info() gives us all of the information from the
* PNG file before the first IDAT (image data chunk).
*/
png_read_info(png_ptr, info_ptr);
if (info_ptr->height > PNG_UINT_32_MAX/png_sizeof(png_bytep))
png_error(png_ptr, "Image is too high to process with png_read_png()");
/* -------------- image transformations start here ------------------- */
#ifdef PNG_READ_16_TO_8_SUPPORTED
/* Tell libpng to strip 16 bit/color files down to 8 bits per color.
*/
if (transforms & PNG_TRANSFORM_STRIP_16)
png_set_strip_16(png_ptr);
#endif
#ifdef PNG_READ_STRIP_ALPHA_SUPPORTED
/* Strip alpha bytes from the input data without combining with
* the background (not recommended).
*/
if (transforms & PNG_TRANSFORM_STRIP_ALPHA)
png_set_strip_alpha(png_ptr);
#endif
#if defined(PNG_READ_PACK_SUPPORTED) && !defined(PNG_READ_EXPAND_SUPPORTED)
/* Extract multiple pixels with bit depths of 1, 2, or 4 from a single
* byte into separate bytes (useful for paletted and grayscale images).
*/
if (transforms & PNG_TRANSFORM_PACKING)
png_set_packing(png_ptr);
#endif
#ifdef PNG_READ_PACKSWAP_SUPPORTED
/* Change the order of packed pixels to least significant bit first
* (not useful if you are using png_set_packing).
*/
if (transforms & PNG_TRANSFORM_PACKSWAP)
png_set_packswap(png_ptr);
#endif
#ifdef PNG_READ_EXPAND_SUPPORTED
/* Expand paletted colors into true RGB triplets
* Expand grayscale images to full 8 bits from 1, 2, or 4 bits/pixel
* Expand paletted or RGB images with transparency to full alpha
* channels so the data will be available as RGBA quartets.
*/
if (transforms & PNG_TRANSFORM_EXPAND)
if ((png_ptr->bit_depth < 8) ||
(png_ptr->color_type == PNG_COLOR_TYPE_PALETTE) ||
(png_get_valid(png_ptr, info_ptr, PNG_INFO_tRNS)))
png_set_expand(png_ptr);
#endif
/* We don't handle background color or gamma transformation or dithering.
*/
#ifdef PNG_READ_INVERT_SUPPORTED
/* Invert monochrome files to have 0 as white and 1 as black
*/
if (transforms & PNG_TRANSFORM_INVERT_MONO)
png_set_invert_mono(png_ptr);
#endif
#ifdef PNG_READ_SHIFT_SUPPORTED
/* If you want to shift the pixel values from the range [0,255] or
* [0,65535] to the original [0,7] or [0,31], or whatever range the
* colors were originally in:
*/
if ((transforms & PNG_TRANSFORM_SHIFT)
&& png_get_valid(png_ptr, info_ptr, PNG_INFO_sBIT))
{
png_color_8p sig_bit;
png_get_sBIT(png_ptr, info_ptr, &sig_bit);
png_set_shift(png_ptr, sig_bit);
}
#endif
#ifdef PNG_READ_BGR_SUPPORTED
/* Flip the RGB pixels to BGR (or RGBA to BGRA)
*/
if (transforms & PNG_TRANSFORM_BGR)
png_set_bgr(png_ptr);
#endif
#ifdef PNG_READ_SWAP_ALPHA_SUPPORTED
/* Swap the RGBA or GA data to ARGB or AG (or BGRA to ABGR)
*/
if (transforms & PNG_TRANSFORM_SWAP_ALPHA)
png_set_swap_alpha(png_ptr);
#endif
#ifdef PNG_READ_SWAP_SUPPORTED
/* Swap bytes of 16 bit files to least significant byte first
*/
if (transforms & PNG_TRANSFORM_SWAP_ENDIAN)
png_set_swap(png_ptr);
#endif
/* Added at libpng-1.2.41 */
#ifdef PNG_READ_INVERT_ALPHA_SUPPORTED
/* Invert the alpha channel from opacity to transparency
*/
if (transforms & PNG_TRANSFORM_INVERT_ALPHA)
png_set_invert_alpha(png_ptr);
#endif
/* Added at libpng-1.2.41 */
#ifdef PNG_READ_GRAY_TO_RGB_SUPPORTED
/* Expand grayscale image to RGB
*/
if (transforms & PNG_TRANSFORM_GRAY_TO_RGB)
png_set_gray_to_rgb(png_ptr);
#endif
/* We don't handle adding filler bytes */
/* Optional call to gamma correct and add the background to the palette
* and update info structure. REQUIRED if you are expecting libpng to
* update the palette for you (i.e., you selected such a transform above).
*/
png_read_update_info(png_ptr, info_ptr);
/* -------------- image transformations end here ------------------- */
png_free_data(png_ptr, info_ptr, PNG_FREE_ROWS, 0);
if (info_ptr->row_pointers == NULL)
{
png_uint_32 iptr;
info_ptr->row_pointers = (png_bytepp)png_malloc(png_ptr,
info_ptr->height * png_sizeof(png_bytep));
for (iptr=0; iptr<info_ptr->height; iptr++)
info_ptr->row_pointers[iptr] = NULL;
info_ptr->free_me |= PNG_FREE_ROWS;
for (row = 0; row < (int)info_ptr->height; row++)
info_ptr->row_pointers[row] = (png_bytep)png_malloc(png_ptr,
png_get_rowbytes(png_ptr, info_ptr));
}
png_read_image(png_ptr, info_ptr->row_pointers);
info_ptr->valid |= PNG_INFO_IDAT;
/* Read rest of file, and get additional chunks in info_ptr - REQUIRED */
png_read_end(png_ptr, info_ptr);
transforms = transforms; /* Quiet compiler warnings */
params = params;
}
/* 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");
if (png_ptr == NULL || info_ptr == NULL)
return;
/* 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;
#ifdef PNG_IO_STATE_SUPPORTED
png_ptr->io_state = PNG_IO_READING | PNG_IO_SIGNATURE;
#endif
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 (;;)
{
PNG_IHDR;
PNG_IDAT;
PNG_IEND;
PNG_PLTE;
#ifdef PNG_READ_bKGD_SUPPORTED
PNG_bKGD;
#endif
#ifdef PNG_READ_cHRM_SUPPORTED
PNG_cHRM;
#endif
#ifdef PNG_READ_gAMA_SUPPORTED
PNG_gAMA;
#endif
#ifdef PNG_READ_hIST_SUPPORTED
PNG_hIST;
#endif
#ifdef PNG_READ_iCCP_SUPPORTED
PNG_iCCP;
#endif
#ifdef PNG_READ_iTXt_SUPPORTED
PNG_iTXt;
#endif
#ifdef PNG_READ_oFFs_SUPPORTED
PNG_oFFs;
#endif
#ifdef PNG_READ_pCAL_SUPPORTED
PNG_pCAL;
#endif
#ifdef PNG_READ_pHYs_SUPPORTED
PNG_pHYs;
#endif
#ifdef PNG_READ_sBIT_SUPPORTED
PNG_sBIT;
#endif
#ifdef PNG_READ_sCAL_SUPPORTED
PNG_sCAL;
#endif
#ifdef PNG_READ_sPLT_SUPPORTED
PNG_sPLT;
#endif
#ifdef PNG_READ_sRGB_SUPPORTED
PNG_sRGB;
#endif
#ifdef PNG_READ_tEXt_SUPPORTED
PNG_tEXt;
#endif
#ifdef PNG_READ_tIME_SUPPORTED
PNG_tIME;
#endif
#ifdef PNG_READ_tRNS_SUPPORTED
PNG_tRNS;
#endif
#ifdef PNG_READ_zTXt_SUPPORTED
PNG_zTXt;
#endif
png_uint_32 length = png_read_chunk_header(png_ptr);
PNG_CONST png_bytep chunk_name = png_ptr->chunk_name;
/* This should be a binary subdivision search or a hash for
* matching the chunk name rather than a linear search.
*/
if (!png_memcmp(chunk_name, png_IDAT, 4))
if (png_ptr->mode & PNG_AFTER_IDAT)
png_ptr->mode |= PNG_HAVE_CHUNK_AFTER_IDAT;
if (!png_memcmp(chunk_name, png_IHDR, 4))
png_handle_IHDR(png_ptr, info_ptr, length);
else if (!png_memcmp(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, chunk_name))
{
if (!png_memcmp(chunk_name, png_IDAT, 4))
png_ptr->mode |= PNG_HAVE_IDAT;
png_handle_unknown(png_ptr, info_ptr, length);
if (!png_memcmp(chunk_name, png_PLTE, 4))
png_ptr->mode |= PNG_HAVE_PLTE;
else if (!png_memcmp(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(chunk_name, png_PLTE, 4))
png_handle_PLTE(png_ptr, info_ptr, length);
else if (!png_memcmp(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;
}
#ifdef PNG_READ_bKGD_SUPPORTED
else if (!png_memcmp(chunk_name, png_bKGD, 4))
png_handle_bKGD(png_ptr, info_ptr, length);
#endif
#ifdef PNG_READ_cHRM_SUPPORTED
else if (!png_memcmp(chunk_name, png_cHRM, 4))
png_handle_cHRM(png_ptr, info_ptr, length);
#endif
#ifdef PNG_READ_gAMA_SUPPORTED
else if (!png_memcmp(chunk_name, png_gAMA, 4))
png_handle_gAMA(png_ptr, info_ptr, length);
#endif
#ifdef PNG_READ_hIST_SUPPORTED
else if (!png_memcmp(chunk_name, png_hIST, 4))
png_handle_hIST(png_ptr, info_ptr, length);
#endif
#ifdef PNG_READ_oFFs_SUPPORTED
else if (!png_memcmp(chunk_name, png_oFFs, 4))
png_handle_oFFs(png_ptr, info_ptr, length);
#endif
#ifdef PNG_READ_pCAL_SUPPORTED
else if (!png_memcmp(chunk_name, png_pCAL, 4))
png_handle_pCAL(png_ptr, info_ptr, length);
#endif
#ifdef PNG_READ_sCAL_SUPPORTED
else if (!png_memcmp(chunk_name, png_sCAL, 4))
png_handle_sCAL(png_ptr, info_ptr, length);
#endif
#ifdef PNG_READ_pHYs_SUPPORTED
else if (!png_memcmp(chunk_name, png_pHYs, 4))
png_handle_pHYs(png_ptr, info_ptr, length);
#endif
#ifdef PNG_READ_sBIT_SUPPORTED
else if (!png_memcmp(chunk_name, png_sBIT, 4))
png_handle_sBIT(png_ptr, info_ptr, length);
#endif
#ifdef PNG_READ_sRGB_SUPPORTED
else if (!png_memcmp(chunk_name, png_sRGB, 4))
png_handle_sRGB(png_ptr, info_ptr, length);
#endif
#ifdef PNG_READ_iCCP_SUPPORTED
else if (!png_memcmp(chunk_name, png_iCCP, 4))
png_handle_iCCP(png_ptr, info_ptr, length);
#endif
#ifdef PNG_READ_sPLT_SUPPORTED
else if (!png_memcmp(chunk_name, png_sPLT, 4))
png_handle_sPLT(png_ptr, info_ptr, length);
#endif
#ifdef PNG_READ_tEXt_SUPPORTED
else if (!png_memcmp(chunk_name, png_tEXt, 4))
png_handle_tEXt(png_ptr, info_ptr, length);
#endif
#ifdef PNG_READ_tIME_SUPPORTED
else if (!png_memcmp(chunk_name, png_tIME, 4))
png_handle_tIME(png_ptr, info_ptr, length);
#endif
#ifdef PNG_READ_tRNS_SUPPORTED
else if (!png_memcmp(chunk_name, png_tRNS, 4))
png_handle_tRNS(png_ptr, info_ptr, length);
#endif
#ifdef PNG_READ_zTXt_SUPPORTED
else if (!png_memcmp(chunk_name, png_zTXt, 4))
png_handle_zTXt(png_ptr, info_ptr, length);
#endif
#ifdef PNG_READ_iTXt_SUPPORTED
else if (!png_memcmp(chunk_name, png_iTXt, 4))
png_handle_iTXt(png_ptr, info_ptr, length);
#endif
else
png_handle_unknown(png_ptr, info_ptr, length);
}
}
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))
{
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)
{
if (png_ptr->mode & PNG_AFTER_IDAT)
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))
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->mode |= PNG_HAVE_IDAT;
png_ptr->process_mode = PNG_READ_IDAT_MODE;
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");
}
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 ((keep = png_chunk_unknown_handling(png_ptr, chunk_name)) != 0)
{
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, keep);
if (chunk_name == png_PLTE)
png_ptr->mode |= PNG_HAVE_PLTE;
}
#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)
{
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)
{
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_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 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_process_row(png_structrp png_ptr)
{
/* 1.5.6: row_info moved out of png_struct to a local here. */
png_row_info row_info;
row_info.width = png_ptr->iwidth; /* NOTE: width of current interlaced row */
row_info.color_type = png_ptr->color_type;
row_info.bit_depth = png_ptr->bit_depth;
row_info.channels = png_ptr->channels;
row_info.pixel_depth = png_ptr->pixel_depth;
row_info.rowbytes = PNG_ROWBYTES(row_info.pixel_depth, row_info.width);
if (png_ptr->row_buf[0] > PNG_FILTER_VALUE_NONE)
{
if (png_ptr->row_buf[0] < PNG_FILTER_VALUE_LAST)
png_read_filter_row(png_ptr, &row_info, png_ptr->row_buf + 1,
png_ptr->prev_row + 1, png_ptr->row_buf[0]);
else
png_error(png_ptr, "bad adaptive filter value");
}
/* libpng 1.5.6: the following line was copying png_ptr->rowbytes before
* 1.5.6, while the buffer really is this big in current versions of libpng
* it may not be in the future, so this was changed just to copy the
* interlaced row count:
*/
memcpy(png_ptr->prev_row, png_ptr->row_buf, row_info.rowbytes + 1);
#ifdef PNG_READ_TRANSFORMS_SUPPORTED
if (png_ptr->transformations != 0)
png_do_read_transformations(png_ptr, &row_info);
#endif
/* The transformed pixel depth should match the depth now in row_info. */
if (png_ptr->transformed_pixel_depth == 0)
{
png_ptr->transformed_pixel_depth = row_info.pixel_depth;
if (row_info.pixel_depth > png_ptr->maximum_pixel_depth)
png_error(png_ptr, "progressive row overflow");
}
else if (png_ptr->transformed_pixel_depth != row_info.pixel_depth)
png_error(png_ptr, "internal progressive row size calculation error");
#ifdef PNG_READ_INTERLACING_SUPPORTED
/* Expand interlaced rows to full size */
if (png_ptr->interlaced != 0 &&
(png_ptr->transformations & PNG_INTERLACE) != 0)
{
if (png_ptr->pass < 6)
png_do_read_interlace(&row_info, png_ptr->row_buf + 1, png_ptr->pass,
png_ptr->transformations);
switch (png_ptr->pass)
{
case 0:
{
int i;
for (i = 0; i < 8 && png_ptr->pass == 0; i++)
{
png_push_have_row(png_ptr, png_ptr->row_buf + 1);
png_read_push_finish_row(png_ptr); /* Updates png_ptr->pass */
}
if (png_ptr->pass == 2) /* Pass 1 might be empty */
{
for (i = 0; i < 4 && png_ptr->pass == 2; i++)
{
png_push_have_row(png_ptr, NULL);
png_read_push_finish_row(png_ptr);
}
}
if (png_ptr->pass == 4 && png_ptr->height <= 4)
{
for (i = 0; i < 2 && png_ptr->pass == 4; i++)
{
png_push_have_row(png_ptr, NULL);
png_read_push_finish_row(png_ptr);
}
}
if (png_ptr->pass == 6 && png_ptr->height <= 4)
{
png_push_have_row(png_ptr, NULL);
png_read_push_finish_row(png_ptr);
}
break;
}
case 1:
{
int i;
for (i = 0; i < 8 && png_ptr->pass == 1; i++)
{
png_push_have_row(png_ptr, png_ptr->row_buf + 1);
png_read_push_finish_row(png_ptr);
}
if (png_ptr->pass == 2) /* Skip top 4 generated rows */
{
for (i = 0; i < 4 && png_ptr->pass == 2; i++)
{
png_push_have_row(png_ptr, NULL);
png_read_push_finish_row(png_ptr);
}
}
break;
}
case 2:
{
int i;
for (i = 0; i < 4 && png_ptr->pass == 2; i++)
{
png_push_have_row(png_ptr, png_ptr->row_buf + 1);
png_read_push_finish_row(png_ptr);
}
for (i = 0; i < 4 && png_ptr->pass == 2; i++)
{
png_push_have_row(png_ptr, NULL);
png_read_push_finish_row(png_ptr);
}
if (png_ptr->pass == 4) /* Pass 3 might be empty */
{
for (i = 0; i < 2 && png_ptr->pass == 4; i++)
{
png_push_have_row(png_ptr, NULL);
png_read_push_finish_row(png_ptr);
}
}
break;
}
case 3:
{
int i;
for (i = 0; i < 4 && png_ptr->pass == 3; i++)
{
png_push_have_row(png_ptr, png_ptr->row_buf + 1);
png_read_push_finish_row(png_ptr);
}
if (png_ptr->pass == 4) /* Skip top two generated rows */
{
for (i = 0; i < 2 && png_ptr->pass == 4; i++)
{
png_push_have_row(png_ptr, NULL);
png_read_push_finish_row(png_ptr);
}
}
break;
}
case 4:
{
int i;
for (i = 0; i < 2 && png_ptr->pass == 4; i++)
{
png_push_have_row(png_ptr, png_ptr->row_buf + 1);
png_read_push_finish_row(png_ptr);
}
for (i = 0; i < 2 && png_ptr->pass == 4; i++)
{
png_push_have_row(png_ptr, NULL);
png_read_push_finish_row(png_ptr);
}
if (png_ptr->pass == 6) /* Pass 5 might be empty */
{
png_push_have_row(png_ptr, NULL);
png_read_push_finish_row(png_ptr);
}
break;
}
case 5:
{
int i;
for (i = 0; i < 2 && png_ptr->pass == 5; i++)
{
png_push_have_row(png_ptr, png_ptr->row_buf + 1);
png_read_push_finish_row(png_ptr);
}
if (png_ptr->pass == 6) /* Skip top generated row */
{
png_push_have_row(png_ptr, NULL);
png_read_push_finish_row(png_ptr);
}
break;
}
default:
case 6:
{
png_push_have_row(png_ptr, png_ptr->row_buf + 1);
png_read_push_finish_row(png_ptr);
if (png_ptr->pass != 6)
break;
png_push_have_row(png_ptr, NULL);
png_read_push_finish_row(png_ptr);
}
}
}
else
{
png_push_have_row(png_ptr, png_ptr->row_buf + 1);
png_read_push_finish_row(png_ptr);
}
}
/* 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");
/* save jump buffer and error functions */
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_GLOBAL_ARRAYS */
png_read_data(png_ptr, chunk_length, 4);
length = png_get_uint_32(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 (length > PNG_MAX_UINT)
png_error(png_ptr, "Invalid chunk length.");
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));
}
/* read_data:
* Custom read function to use Allegro packfile routines,
* rather than C streams (so we can read from datafiles!)
*/
static void read_data(png_structp png_ptr, png_bytep data, png_uint_32 length)
{
ALLEGRO_FILE *f = (ALLEGRO_FILE *)png_get_io_ptr(png_ptr);
if ((png_uint_32) al_fread(f, data, length) != length)
png_error(png_ptr, "read error (loadpng calling al_fs_entry_read)");
}
/* Alternate create PNG structure for reading, and allocate any memory needed. */
png_structp PNGAPI
png_create_read_struct_2(png_const_charp user_png_ver, png_voidp error_ptr,
png_error_ptr error_fn, png_error_ptr warn_fn, png_voidp mem_ptr,
png_malloc_ptr malloc_fn, png_free_ptr free_fn)
{
#endif /* PNG_USER_MEM_SUPPORTED */
png_structp png_ptr;
#ifdef PNG_SETJMP_SUPPORTED
#ifdef USE_FAR_KEYWORD
jmp_buf jmpbuf;
#endif
#endif
int i;
png_debug(1, "in png_create_read_struct\n");
#ifdef PNG_USER_MEM_SUPPORTED
png_ptr = (png_structp)png_create_struct_2(PNG_STRUCT_PNG,
(png_malloc_ptr)malloc_fn, (png_voidp)mem_ptr);
#else
png_ptr = (png_structp)png_create_struct(PNG_STRUCT_PNG);
#endif
if (png_ptr == NULL)
return (NULL);
#if !defined(PNG_1_0_X)
#ifdef PNG_ASSEMBLER_CODE_SUPPORTED
png_init_mmx_flags(png_ptr); /* 1.2.0 addition */
#endif
#endif /* PNG_1_0_X */
#ifdef PNG_SETJMP_SUPPORTED
#ifdef USE_FAR_KEYWORD
if (setjmp(jmpbuf))
#else
if (setjmp(png_ptr->jmpbuf))
#endif
{
png_free(png_ptr, png_ptr->zbuf);
png_ptr->zbuf=NULL;
#ifdef PNG_USER_MEM_SUPPORTED
png_destroy_struct_2((png_voidp)png_ptr,
(png_free_ptr)free_fn,
(png_voidp)mem_ptr);
#else
png_destroy_struct((png_voidp)png_ptr);
#endif
return (NULL);
}
#ifdef USE_FAR_KEYWORD
png_memcpy(png_ptr->jmpbuf,jmpbuf,sizeof(jmp_buf));
#endif
#endif
#ifdef PNG_USER_MEM_SUPPORTED
png_set_mem_fn(png_ptr, mem_ptr, malloc_fn, free_fn);
#endif
png_set_error_fn(png_ptr, error_ptr, error_fn, warn_fn);
i=0;
do
{
if(user_png_ver[i] != png_libpng_ver[i])
png_ptr->flags |= PNG_FLAG_LIBRARY_MISMATCH;
} while (png_libpng_ver[i++]);
if (png_ptr->flags & PNG_FLAG_LIBRARY_MISMATCH)
{
/* Libpng 0.90 and later are binary incompatible with libpng 0.89, so
* we must recompile any applications that use any older library version.
* For versions after libpng 1.0, we will be compatible, so we need
* only check the first digit.
*/
if (user_png_ver == NULL || user_png_ver[0] != png_libpng_ver[0] ||
(user_png_ver[0] == '1' && user_png_ver[2] != png_libpng_ver[2]) ||
(user_png_ver[0] == '0' && user_png_ver[2] < '9'))
{
#if !defined(PNG_NO_STDIO) && !defined(_WIN32_WCE)
char msg[80];
if (user_png_ver)
{
sprintf(msg, "Application was compiled with png.h from libpng-%.20s",
user_png_ver);
png_warning(png_ptr, msg);
}
sprintf(msg, "Application is running with png.c from libpng-%.20s",
png_libpng_ver);
png_warning(png_ptr, msg);
#endif
#ifdef PNG_ERROR_NUMBERS_SUPPORTED
png_ptr->flags=0;
#endif
png_error(png_ptr,
"Incompatible libpng version in application and library");
}
}
/* initialize zbuf - compression buffer */
png_ptr->zbuf_size = PNG_ZBUF_SIZE;
png_ptr->zbuf = (png_bytep)png_malloc(png_ptr,
(png_uint_32)png_ptr->zbuf_size);
png_ptr->zstream.zalloc = png_zalloc;
png_ptr->zstream.zfree = png_zfree;
png_ptr->zstream.opaque = (voidpf)png_ptr;
switch (inflateInit(&png_ptr->zstream))
{
case Z_OK: /* Do nothing */ break;
case Z_MEM_ERROR:
case Z_STREAM_ERROR: png_error(png_ptr, "zlib memory error"); break;
case Z_VERSION_ERROR: png_error(png_ptr, "zlib version error"); break;
default: png_error(png_ptr, "Unknown zlib error");
}
png_ptr->zstream.next_out = png_ptr->zbuf;
png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;
png_set_read_fn(png_ptr, png_voidp_NULL, png_rw_ptr_NULL);
#ifdef PNG_SETJMP_SUPPORTED
/* Applications that neglect to set up their own setjmp() and then encounter
a png_error() will longjmp here. Since the jmpbuf is then meaningless we
abort instead of returning. */
#ifdef USE_FAR_KEYWORD
if (setjmp(jmpbuf))
PNG_ABORT();
png_memcpy(png_ptr->jmpbuf,jmpbuf,sizeof(jmp_buf));
#else
if (setjmp(png_ptr->jmpbuf))
PNG_ABORT();
#endif
#endif
return (png_ptr);
}
/* 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");
/* save jump buffer and error functions */
/* 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_GLOBAL_ARRAYS */
png_byte chunk_length[4];
png_uint_32 length;
png_read_data(png_ptr, chunk_length, 4);
length = png_get_uint_32(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);
if (length > PNG_MAX_UINT)
png_error(png_ptr, "Invalid chunk 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);
}
}
void PNGAPI
png_read_init_3(png_structpp ptr_ptr, png_const_charp user_png_ver,
png_size_t png_struct_size)
{
#ifdef PNG_SETJMP_SUPPORTED
jmp_buf tmp_jmp; /* to save current jump buffer */
#endif
int i=0;
png_structp png_ptr=*ptr_ptr;
do
{
if(user_png_ver[i] != png_libpng_ver[i])
{
#ifdef PNG_LEGACY_SUPPORTED
png_ptr->flags |= PNG_FLAG_LIBRARY_MISMATCH;
#else
png_ptr->warning_fn=NULL;
png_warning(png_ptr,
"Application uses deprecated png_read_init() and should be recompiled.");
break;
#endif
}
} while (png_libpng_ver[i++]);
png_debug(1, "in png_read_init_3\n");
#ifdef PNG_SETJMP_SUPPORTED
/* save jump buffer and error functions */
png_memcpy(tmp_jmp, png_ptr->jmpbuf, sizeof (jmp_buf));
#endif
if(sizeof(png_struct) > png_struct_size)
{
png_destroy_struct(png_ptr);
*ptr_ptr = (png_structp)png_create_struct(PNG_STRUCT_PNG);
png_ptr = *ptr_ptr;
}
/* reset all variables to 0 */
png_memset(png_ptr, 0, sizeof (png_struct));
#ifdef PNG_SETJMP_SUPPORTED
/* restore jump buffer */
png_memcpy(png_ptr->jmpbuf, tmp_jmp, sizeof (jmp_buf));
#endif
/* initialize zbuf - compression buffer */
png_ptr->zbuf_size = PNG_ZBUF_SIZE;
png_ptr->zbuf = (png_bytep)png_malloc(png_ptr,
(png_uint_32)png_ptr->zbuf_size);
png_ptr->zstream.zalloc = png_zalloc;
png_ptr->zstream.zfree = png_zfree;
png_ptr->zstream.opaque = (voidpf)png_ptr;
switch (inflateInit(&png_ptr->zstream))
{
case Z_OK: /* Do nothing */ break;
case Z_MEM_ERROR:
case Z_STREAM_ERROR: png_error(png_ptr, "zlib memory"); break;
case Z_VERSION_ERROR: png_error(png_ptr, "zlib version"); break;
default: png_error(png_ptr, "Unknown zlib error");
}
png_ptr->zstream.next_out = png_ptr->zbuf;
png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;
png_set_read_fn(png_ptr, png_voidp_NULL, png_rw_ptr_NULL);
}
/* Alternate create PNG structure for reading, and allocate any memory needed. */
png_structp PNGAPI
png_create_read_struct_2(png_const_charp user_png_ver, png_voidp error_ptr,
png_error_ptr error_fn, png_error_ptr warn_fn, png_voidp mem_ptr,
png_malloc_ptr malloc_fn, png_free_ptr free_fn)
{
#endif /* PNG_USER_MEM_SUPPORTED */
volatile png_structp png_ptr;
#ifdef PNG_SETJMP_SUPPORTED
#ifdef USE_FAR_KEYWORD
jmp_buf jmpbuf;
#endif
#endif
int i;
png_debug(1, "in png_create_read_struct\n");
#ifdef PNG_USER_MEM_SUPPORTED
if ((png_ptr = (png_structp)png_create_struct_2(PNG_STRUCT_PNG,
(png_malloc_ptr)malloc_fn, (png_voidp)mem_ptr)) == NULL)
#else
if ((png_ptr = (png_structp)png_create_struct(PNG_STRUCT_PNG)) == NULL)
#endif
{
return (png_structp)NULL;
}
#ifdef PNG_SETJMP_SUPPORTED
#ifdef USE_FAR_KEYWORD
if (setjmp(jmpbuf))
#else
if (setjmp(png_ptr->jmpbuf))
#endif
{
png_free(png_ptr, png_ptr->zbuf);
png_ptr->zbuf=NULL;
png_destroy_struct(png_ptr);
return (png_structp)NULL;
}
#ifdef USE_FAR_KEYWORD
png_memcpy(png_ptr->jmpbuf,jmpbuf,sizeof(jmp_buf));
#endif
#endif
#ifdef PNG_USER_MEM_SUPPORTED
png_set_mem_fn(png_ptr, mem_ptr, malloc_fn, free_fn);
#endif
png_set_error_fn(png_ptr, error_ptr, error_fn, warn_fn);
i=0;
do
{
if(user_png_ver[i] != png_libpng_ver[i])
png_ptr->flags |= PNG_FLAG_LIBRARY_MISMATCH;
} while (png_libpng_ver[i++]);
if (png_ptr->flags & PNG_FLAG_LIBRARY_MISMATCH)
{
/* Libpng 0.90 and later are binary incompatible with libpng 0.89, so
* we must recompile any applications that use any older library version.
* For versions after libpng 1.0, we will be compatible, so we need
* only check the first digit.
*/
if (user_png_ver == NULL || user_png_ver[0] != png_libpng_ver[0] ||
(user_png_ver[0] == '1' && user_png_ver[2] != png_libpng_ver[2]) ||
(user_png_ver[0] == '0' && user_png_ver[2] < '9'))
{
#if !defined(PNG_NO_STDIO) && !defined(_WIN32_WCE)
char msg[80];
if (user_png_ver)
{
sprintf(msg, "Application was compiled with png.h from libpng-%.20s",
user_png_ver);
png_warning(png_ptr, msg);
}
sprintf(msg, "Application is running with png.c from libpng-%.20s",
png_libpng_ver);
png_warning(png_ptr, msg);
#endif
#ifdef PNG_ERROR_NUMBERS_SUPPORTED
png_ptr->flags=0;
#endif
png_error(png_ptr,
"Incompatible libpng version in application and library");
}
/* Libpng 1.0.6 was not binary compatible, due to insertion of the
info_ptr->free_me member. Libpng-1.0.1 and earlier were not
compatible due to insertion of the user transform function. Note
to maintainer: this test can be removed from version 1.2.0 and
beyond because the previous test would have already rejected it. */
if (user_png_ver[0] == '1' && user_png_ver[2] == '0' &&
(user_png_ver[4] < '2' || user_png_ver[4] == '6') &&
user_png_ver[5] == '\0')
{
#if !defined(PNG_NO_STDIO) && !defined(_WIN32_WCE)
char msg[80];
if (user_png_ver)
{
sprintf(msg, "Application was compiled with png.h from libpng-%.20s",
user_png_ver);
png_warning(png_ptr, msg);
}
sprintf(msg, "Application is running with png.c from libpng-%.20s",
png_libpng_ver);
png_warning(png_ptr, msg);
#endif
#ifdef PNG_ERROR_NUMBERS_SUPPORTED
png_ptr->flags=0;
#endif
png_error(png_ptr,
"Application must be recompiled; versions <= 1.0.6 were incompatible");
}
}
/* initialize zbuf - compression buffer */
png_ptr->zbuf_size = PNG_ZBUF_SIZE;
png_ptr->zbuf = (png_bytep)png_malloc(png_ptr,
(png_uint_32)png_ptr->zbuf_size);
png_ptr->zstream.zalloc = png_zalloc;
png_ptr->zstream.zfree = png_zfree;
png_ptr->zstream.opaque = (voidpf)png_ptr;
switch (inflateInit(&png_ptr->zstream))
{
case Z_OK: /* Do nothing */ break;
case Z_MEM_ERROR:
case Z_STREAM_ERROR: png_error(png_ptr, "zlib memory error"); break;
case Z_VERSION_ERROR: png_error(png_ptr, "zlib version error"); break;
default: png_error(png_ptr, "Unknown zlib error");
}
png_ptr->zstream.next_out = png_ptr->zbuf;
png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;
png_set_read_fn(png_ptr, NULL, NULL);
return (png_ptr);
}
void /* PRIVATE */
png_push_read_IDAT(png_structrp png_ptr)
{
if (!(png_ptr->mode & PNG_HAVE_CHUNK_HEADER))
{
png_byte chunk_length[4];
png_byte chunk_tag[4];
/* TODO: this code can be commoned up with the same code in push_read */
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_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))
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;
png_ptr->zowner = 0;
}
}
void PNGAPI
png_read_row(png_structp png_ptr, png_bytep row, png_bytep dsp_row)
{
PNG_IDAT;
PNG_CONST int png_pass_dsp_mask[7] = {0xff, 0x0f, 0xff, 0x33, 0xff, 0x55,
0xff};
PNG_CONST int png_pass_mask[7] = {0x80, 0x08, 0x88, 0x22, 0xaa, 0x55, 0xff};
int ret;
if (png_ptr == NULL)
return;
png_debug2(1, "in png_read_row (row %lu, pass %d)",
(unsigned long) 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
}
#ifdef 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_ROWBYTES(png_ptr->pixel_depth,
png_ptr->iwidth) + 1);
do
{
if (!(png_ptr->zstream.avail_in))
{
while (!png_ptr->idat_size)
{
png_crc_finish(png_ptr, 0);
png_ptr->idat_size = png_read_chunk_header(png_ptr);
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_benign_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(png_ptr->prev_row, png_ptr->row_buf, png_ptr->rowbytes + 1);
#ifdef 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);
#ifdef 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);
}
static int
read_png(FILE *fp)
{
png_structp png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING,0,0,0);
png_infop info_ptr = NULL;
png_bytep row = NULL, display = NULL;
if (png_ptr == NULL)
return 0;
if (setjmp(png_jmpbuf(png_ptr)))
{
png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
if (row != NULL) free(row);
if (display != NULL) free(display);
return 0;
}
png_init_io(png_ptr, fp);
info_ptr = png_create_info_struct(png_ptr);
if (info_ptr == NULL)
png_error(png_ptr, "OOM allocating info structure");
png_set_keep_unknown_chunks(png_ptr, PNG_HANDLE_CHUNK_ALWAYS, NULL, 0);
png_read_info(png_ptr, info_ptr);
{
png_size_t rowbytes = png_get_rowbytes(png_ptr, info_ptr);
row = malloc(rowbytes);
display = malloc(rowbytes);
if (row == NULL || display == NULL)
png_error(png_ptr, "OOM allocating row buffers");
{
png_uint_32 height = png_get_image_height(png_ptr, info_ptr);
int passes = png_set_interlace_handling(png_ptr);
int pass;
png_start_read_image(png_ptr);
for (pass = 0; pass < passes; ++pass)
{
png_uint_32 y = height;
/* NOTE: this trashes the row each time; interlace handling won't
* work, but this avoids memory thrashing for speed testing.
*/
while (y-- > 0)
png_read_row(png_ptr, row, display);
}
}
}
/* Make sure to read to the end of the file: */
png_read_end(png_ptr, info_ptr);
png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
free(row);
free(display);
return 1;
}
/* write_data:
* Custom write function to use Allegro packfile routines,
* rather than C streams.
*/
static void write_data(png_structp png_ptr, png_bytep data, png_uint_32 length)
{
ALLEGRO_FILE *f = (ALLEGRO_FILE *)png_get_io_ptr(png_ptr);
if ((png_uint_32) al_fwrite(f, data, length) != length)
png_error(png_ptr, "write error (loadpng calling al_fs_entry_write)");
}
void PNGAPI
png_set_pCAL(png_structp png_ptr, png_infop info_ptr,
png_const_charp purpose, png_int_32 X0, png_int_32 X1, int type,
int nparams, png_const_charp units, png_charpp params)
{
png_size_t length;
int i;
png_debug1(1, "in %s storage function", "pCAL");
if (png_ptr == NULL || info_ptr == NULL)
return;
length = png_strlen(purpose) + 1;
png_debug1(3, "allocating purpose for info (%lu bytes)",
(unsigned long)length);
/* TODO: validate format of calibration name and unit name */
/* Check that the type matches the specification. */
if (type < 0 || type > 3)
png_error(png_ptr, "Invalid pCAL equation type");
/* Validate params[nparams] */
for (i=0; i<nparams; ++i)
if (!png_check_fp_string(params[i], png_strlen(params[i])))
png_error(png_ptr, "Invalid format for pCAL parameter");
info_ptr->pcal_purpose = (png_charp)png_malloc_warn(png_ptr, length);
if (info_ptr->pcal_purpose == NULL)
{
png_warning(png_ptr, "Insufficient memory for pCAL purpose");
return;
}
png_memcpy(info_ptr->pcal_purpose, purpose, length);
png_debug(3, "storing X0, X1, type, and nparams in info");
info_ptr->pcal_X0 = X0;
info_ptr->pcal_X1 = X1;
info_ptr->pcal_type = (png_byte)type;
info_ptr->pcal_nparams = (png_byte)nparams;
length = png_strlen(units) + 1;
png_debug1(3, "allocating units for info (%lu bytes)",
(unsigned long)length);
info_ptr->pcal_units = (png_charp)png_malloc_warn(png_ptr, length);
if (info_ptr->pcal_units == NULL)
{
png_warning(png_ptr, "Insufficient memory for pCAL units");
return;
}
png_memcpy(info_ptr->pcal_units, units, length);
info_ptr->pcal_params = (png_charpp)png_malloc_warn(png_ptr,
(png_size_t)((nparams + 1) * png_sizeof(png_charp)));
if (info_ptr->pcal_params == NULL)
{
png_warning(png_ptr, "Insufficient memory for pCAL params");
return;
}
png_memset(info_ptr->pcal_params, 0, (nparams + 1) * png_sizeof(png_charp));
for (i = 0; i < nparams; i++)
{
length = png_strlen(params[i]) + 1;
png_debug2(3, "allocating parameter %d for info (%lu bytes)", i,
(unsigned long)length);
info_ptr->pcal_params[i] = (png_charp)png_malloc_warn(png_ptr, length);
if (info_ptr->pcal_params[i] == NULL)
{
png_warning(png_ptr, "Insufficient memory for pCAL parameter");
return;
}
png_memcpy(info_ptr->pcal_params[i], params[i], length);
}
info_ptr->valid |= PNG_INFO_pCAL;
info_ptr->free_me |= PNG_FREE_PCAL;
}
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) != 0 ||
png_ptr->num_frames_read > 1)
png_error(png_ptr, "out of place IDAT");
PNG_PUSH_SAVE_BUFFER_IF_FULL
png_push_crc_skip(png_ptr, png_ptr->push_length);
png_ptr->mode &= ~PNG_HAVE_CHUNK_HEADER;
return;
}
else if (chunk_name == png_fdAT)
{
PNG_PUSH_SAVE_BUFFER_IF_LT(4)
png_ensure_sequence_number(png_ptr, 4);
if ((png_ptr->mode & PNG_HAVE_fcTL) == 0)
{
/* Discard trailing fdATs for frames other than the first */
if (png_ptr->num_frames_read < 2)
png_error(png_ptr, "out of place fdAT");
PNG_PUSH_SAVE_BUFFER_IF_FULL
png_push_crc_skip(png_ptr, png_ptr->push_length);
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)
{
PNG_PUSH_SAVE_BUFFER_IF_FULL
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) == 0)
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
{
PNG_PUSH_SAVE_BUFFER_IF_FULL
png_warning(png_ptr, "Skipped (ignored) a chunk "
"between APNG chunks");
png_push_crc_skip(png_ptr, png_ptr->push_length);
png_ptr->mode &= ~PNG_HAVE_CHUNK_HEADER;
return;
}
return;
}
#endif /* READ_APNG */
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->mode |= PNG_HAVE_IDAT;
png_ptr->process_mode = PNG_READ_IDAT_MODE;
if ((png_ptr->mode & PNG_HAVE_CHUNK_AFTER_IDAT) == 0)
if (png_ptr->push_length == 0)
return;
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)
{
PNG_PUSH_SAVE_BUFFER_IF_FULL
png_handle_acTL(png_ptr, info_ptr, png_ptr->push_length);
}
else if (chunk_name == png_fcTL)
{
PNG_PUSH_SAVE_BUFFER_IF_FULL
png_handle_fcTL(png_ptr, info_ptr, png_ptr->push_length);
}
#endif /* READ_APNG */
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 PNGAPI
png_set_sCAL_s(png_structp png_ptr, png_infop info_ptr,
int unit, png_const_charp swidth, png_const_charp sheight)
{
png_size_t lengthw = 0, lengthh = 0;
png_debug1(1, "in %s storage function", "sCAL");
if (png_ptr == NULL || info_ptr == NULL)
return;
/* Double check the unit (should never get here with an invalid
* unit unless this is an API call.)
*/
if (unit != 1 && unit != 2)
png_error(png_ptr, "Invalid sCAL unit");
if (swidth == NULL || (lengthw = png_strlen(swidth)) == 0 ||
swidth[0] == 45 /* '-' */ || !png_check_fp_string(swidth, lengthw))
png_error(png_ptr, "Invalid sCAL width");
if (sheight == NULL || (lengthh = png_strlen(sheight)) == 0 ||
sheight[0] == 45 /* '-' */ || !png_check_fp_string(sheight, lengthh))
png_error(png_ptr, "Invalid sCAL height");
info_ptr->scal_unit = (png_byte)unit;
++lengthw;
png_debug1(3, "allocating unit for info (%u bytes)", (unsigned int)lengthw);
info_ptr->scal_s_width = (png_charp)png_malloc_warn(png_ptr, lengthw);
if (info_ptr->scal_s_width == NULL)
{
png_warning(png_ptr, "Memory allocation failed while processing sCAL");
return;
}
png_memcpy(info_ptr->scal_s_width, swidth, lengthw);
++lengthh;
png_debug1(3, "allocating unit for info (%u bytes)", (unsigned int)lengthh);
info_ptr->scal_s_height = (png_charp)png_malloc_warn(png_ptr, lengthh);
if (info_ptr->scal_s_height == NULL)
{
png_free (png_ptr, info_ptr->scal_s_width);
info_ptr->scal_s_width = NULL;
png_warning(png_ptr, "Memory allocation failed while processing sCAL");
return;
}
png_memcpy(info_ptr->scal_s_height, sheight, lengthh);
info_ptr->valid |= PNG_INFO_sCAL;
info_ptr->free_me |= PNG_FREE_SCAL;
}
void /* PRIVATE */
png_process_IDAT_data(png_structrp png_ptr, png_bytep buffer,
png_size_t buffer_length)
{
/* The caller checks for a non-zero buffer length. */
if (!(buffer_length > 0) || buffer == NULL)
png_error(png_ptr, "No IDAT data (internal error)");
#ifdef PNG_READ_APNG_SUPPORTED
/* If the app is not APNG-aware, decode only the first frame */
if ((png_ptr->apng_flags & PNG_APNG_APP) == 0 &&
png_ptr->num_frames_read > 0)
{
png_ptr->flags |= PNG_FLAG_ZSTREAM_ENDED;
return;
}
#endif
/* This routine must process all the data it has been given
* before returning, calling the row callback as required to
* handle the uncompressed results.
*/
png_ptr->zstream.next_in = buffer;
/* TODO: WARNING: TRUNCATION ERROR: DANGER WILL ROBINSON: */
png_ptr->zstream.avail_in = (uInt)buffer_length;
/* Keep going until the decompressed data is all processed
* or the stream marked as finished.
*/
while (png_ptr->zstream.avail_in > 0 &&
!(png_ptr->flags & PNG_FLAG_ZSTREAM_ENDED))
{
int ret;
/* We have data for zlib, but we must check that zlib
* has someplace to put the results. It doesn't matter
* if we don't expect any results -- it may be the input
* data is just the LZ end code.
*/
if (!(png_ptr->zstream.avail_out > 0))
{
/* TODO: WARNING: TRUNCATION ERROR: DANGER WILL ROBINSON: */
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;
}
/* Using Z_SYNC_FLUSH here means that an unterminated
* LZ stream (a stream with a missing end code) can still
* be handled, otherwise (Z_NO_FLUSH) a future zlib
* implementation might defer output and therefore
* change the current behavior (see comments in inflate.c
* for why this doesn't happen at present with zlib 1.2.5).
*/
ret = inflate(&png_ptr->zstream, Z_SYNC_FLUSH);
/* Check for any failure before proceeding. */
if (ret != Z_OK && ret != Z_STREAM_END)
{
/* Terminate the decompression. */
png_ptr->flags |= PNG_FLAG_ZSTREAM_ENDED;
png_ptr->zowner = 0;
/* This may be a truncated stream (missing or
* damaged end code). Treat that as a warning.
*/
if (png_ptr->row_number >= png_ptr->num_rows ||
png_ptr->pass > 6)
png_warning(png_ptr, "Truncated compressed data in IDAT");
else
png_error(png_ptr, "Decompression error in IDAT");
/* Skip the check on unprocessed input */
return;
}
/* Did inflate output any data? */
if (png_ptr->zstream.next_out != png_ptr->row_buf)
{
/* Is this unexpected data after the last row?
* If it is, artificially terminate the LZ output
* here.
*/
if (png_ptr->row_number >= png_ptr->num_rows ||
png_ptr->pass > 6)
{
/* Extra data. */
png_warning(png_ptr, "Extra compressed data in IDAT");
png_ptr->flags |= PNG_FLAG_ZSTREAM_ENDED;
png_ptr->zowner = 0;
/* Do no more processing; skip the unprocessed
* input check below.
*/
return;
}
/* Do we have a complete row? */
if (png_ptr->zstream.avail_out == 0)
png_push_process_row(png_ptr);
}
/* And check for the end of the stream. */
if (ret == Z_STREAM_END)
png_ptr->flags |= PNG_FLAG_ZSTREAM_ENDED;
}
/* All the data should have been processed, if anything
* is left at this point we have bytes of IDAT data
* after the zlib end code.
*/
if (png_ptr->zstream.avail_in > 0)
png_warning(png_ptr, "Extra compression data in IDAT");
}
png_voidp PNGAPI
png_malloc_default(png_structp png_ptr, png_uint_32 size)
{
png_voidp ret;
#endif /* PNG_USER_MEM_SUPPORTED */
if (png_ptr == NULL || size == 0)
return (NULL);
#ifdef PNG_MAX_MALLOC_64K
if (size > (png_uint_32)65536L)
{
png_warning(png_ptr, "Cannot Allocate > 64K");
ret = NULL;
}
else
#endif
if (size != (size_t)size)
ret = NULL;
else if (size == (png_uint_32)65536L)
{
if (png_ptr->offset_table == NULL)
{
/* try to see if we need to do any of this fancy stuff */
ret = farmalloc(size);
if (ret == NULL || ((png_size_t)ret & 0xffff))
{
int num_blocks;
png_uint_32 total_size;
png_bytep table;
int i;
png_byte huge * hptr;
if (ret != NULL)
{
farfree(ret);
ret = NULL;
}
if(png_ptr->zlib_window_bits > 14)
num_blocks = (int)(1 << (png_ptr->zlib_window_bits - 14));
else
num_blocks = 1;
if (png_ptr->zlib_mem_level >= 7)
num_blocks += (int)(1 << (png_ptr->zlib_mem_level - 7));
else
num_blocks++;
total_size = ((png_uint_32)65536L) * (png_uint_32)num_blocks+16;
table = farmalloc(total_size);
if (table == NULL)
{
#ifndef PNG_USER_MEM_SUPPORTED
if ((png_ptr->flags&PNG_FLAG_MALLOC_NULL_MEM_OK) == 0)
png_error(png_ptr, "Out Of Memory."); /* Note "O" and "M" */
else
png_warning(png_ptr, "Out Of Memory.");
#endif
return (NULL);
}
if ((png_size_t)table & 0xfff0)
{
#ifndef PNG_USER_MEM_SUPPORTED
if ((png_ptr->flags&PNG_FLAG_MALLOC_NULL_MEM_OK) == 0)
png_error(png_ptr,
"Farmalloc didn't return normalized pointer");
else
png_warning(png_ptr,
"Farmalloc didn't return normalized pointer");
#endif
return (NULL);
}
png_ptr->offset_table = table;
png_ptr->offset_table_ptr = farmalloc(num_blocks *
png_sizeof (png_bytep));
if (png_ptr->offset_table_ptr == NULL)
{
#ifndef PNG_USER_MEM_SUPPORTED
if ((png_ptr->flags&PNG_FLAG_MALLOC_NULL_MEM_OK) == 0)
png_error(png_ptr, "Out Of memory."); /* Note "O" and "M" */
else
png_warning(png_ptr, "Out Of memory.");
#endif
return (NULL);
}
hptr = (png_byte huge *)table;
if ((png_size_t)hptr & 0xf)
{
hptr = (png_byte huge *)((long)(hptr) & 0xfffffff0L);
hptr = hptr + 16L; /* "hptr += 16L" fails on Turbo C++ 3.0 */
}
for (i = 0; i < num_blocks; i++)
{
png_ptr->offset_table_ptr[i] = (png_bytep)hptr;
hptr = hptr + (png_uint_32)65536L; /* "+=" fails on TC++3.0 */
}
png_ptr->offset_table_number = num_blocks;
png_ptr->offset_table_count = 0;
png_ptr->offset_table_count_free = 0;
}
}
if (png_ptr->offset_table_count >= png_ptr->offset_table_number)
{
#ifndef PNG_USER_MEM_SUPPORTED
if ((png_ptr->flags&PNG_FLAG_MALLOC_NULL_MEM_OK) == 0)
png_error(png_ptr, "Out of Memory."); /* Note "o" and "M" */
else
png_warning(png_ptr, "Out of Memory.");
#endif
return (NULL);
}
ret = png_ptr->offset_table_ptr[png_ptr->offset_table_count++];
}
else
ret = farmalloc(size);
#ifndef PNG_USER_MEM_SUPPORTED
if (ret == NULL)
{
if ((png_ptr->flags&PNG_FLAG_MALLOC_NULL_MEM_OK) == 0)
png_error(png_ptr, "Out of memory."); /* Note "o" and "m" */
else
png_warning(png_ptr, "Out of memory."); /* Note "o" and "m" */
}
#endif
return (ret);
}
/* write_data:
* Custom write function to use Allegro packfile routines,
* rather than C streams.
*/
static void write_data(png_structp png_ptr, png_bytep data, png_uint_32 length)
{
PACKFILE *f = (PACKFILE *)png_get_io_ptr(png_ptr);
if ((png_uint_32)pack_fwrite(data, length, f) != length)
png_error(png_ptr, "write error (loadpng calling pack_fwrite)");
}
void PNGAPI
png_set_IHDR(png_structp png_ptr, png_infop info_ptr,
png_uint_32 width, png_uint_32 height, int bit_depth,
int color_type, int interlace_type, int compression_type,
int filter_type)
{
int rowbytes_per_pixel;
png_debug1(1, "in %s storage function\n", "IHDR");
if (png_ptr == NULL || info_ptr == NULL)
return;
/* check for width and height valid values */
if (width == 0 || height == 0)
png_error(png_ptr, "Image width or height is zero in IHDR");
if (width > PNG_MAX_UINT || height > PNG_MAX_UINT)
png_error(png_ptr, "Invalid image size in IHDR");
/* check other values */
if (bit_depth != 1 && bit_depth != 2 && bit_depth != 4 &&
bit_depth != 8 && bit_depth != 16)
png_error(png_ptr, "Invalid bit depth in IHDR");
if (color_type < 0 || color_type == 1 ||
color_type == 5 || color_type > 6)
png_error(png_ptr, "Invalid color type in IHDR");
if (((color_type == PNG_COLOR_TYPE_PALETTE) && bit_depth > 8) ||
((color_type == PNG_COLOR_TYPE_RGB ||
color_type == PNG_COLOR_TYPE_GRAY_ALPHA ||
color_type == PNG_COLOR_TYPE_RGB_ALPHA) && bit_depth < 8))
png_error(png_ptr, "Invalid color type/bit depth combination in IHDR");
if (interlace_type >= PNG_INTERLACE_LAST)
png_error(png_ptr, "Unknown interlace method in IHDR");
if (compression_type != PNG_COMPRESSION_TYPE_BASE)
png_error(png_ptr, "Unknown compression method in IHDR");
#if defined(PNG_MNG_FEATURES_SUPPORTED)
/* Accept filter_method 64 (intrapixel differencing) only if
* 1. Libpng was compiled with PNG_MNG_FEATURES_SUPPORTED and
* 2. Libpng did not read a PNG signature (this filter_method is only
* used in PNG datastreams that are embedded in MNG datastreams) and
* 3. The application called png_permit_mng_features with a mask that
* included PNG_FLAG_MNG_FILTER_64 and
* 4. The filter_method is 64 and
* 5. The color_type is RGB or RGBA
*/
if((png_ptr->mode&PNG_HAVE_PNG_SIGNATURE)&&png_ptr->mng_features_permitted)
png_warning(png_ptr,"MNG features are not allowed in a PNG datastream\n");
if(filter_type != PNG_FILTER_TYPE_BASE)
{
if(!((png_ptr->mng_features_permitted & PNG_FLAG_MNG_FILTER_64) &&
(filter_type == PNG_INTRAPIXEL_DIFFERENCING) &&
((png_ptr->mode&PNG_HAVE_PNG_SIGNATURE) == 0) &&
(color_type == PNG_COLOR_TYPE_RGB ||
color_type == PNG_COLOR_TYPE_RGB_ALPHA)))
png_error(png_ptr, "Unknown filter method in IHDR");
if(png_ptr->mode&PNG_HAVE_PNG_SIGNATURE)
png_warning(png_ptr, "Invalid filter method in IHDR");
}
#else
if(filter_type != PNG_FILTER_TYPE_BASE)
png_error(png_ptr, "Unknown filter method in IHDR");
#endif
info_ptr->width = width;
info_ptr->height = height;
info_ptr->bit_depth = (png_byte)bit_depth;
info_ptr->color_type =(png_byte) color_type;
info_ptr->compression_type = (png_byte)compression_type;
info_ptr->filter_type = (png_byte)filter_type;
info_ptr->interlace_type = (png_byte)interlace_type;
if (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
info_ptr->channels = 1;
else if (info_ptr->color_type & PNG_COLOR_MASK_COLOR)
info_ptr->channels = 3;
else
info_ptr->channels = 1;
if (info_ptr->color_type & PNG_COLOR_MASK_ALPHA)
info_ptr->channels++;
info_ptr->pixel_depth = (png_byte)(info_ptr->channels * info_ptr->bit_depth);
/* check for overflow */
rowbytes_per_pixel = (info_ptr->pixel_depth + 7) >> 3;
if (( width > PNG_MAX_UINT/rowbytes_per_pixel))
{
png_warning(png_ptr,
"Width too large to process image data; rowbytes will overflow.");
info_ptr->rowbytes = (png_size_t)0;
}
else
info_ptr->rowbytes = (info_ptr->width * info_ptr->pixel_depth + 7) >> 3;
}
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_32(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_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;
}
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);
}
#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;
}
static void sk_write_fn(png_structp png_ptr, png_bytep data, png_size_t len) {
SkWStream* stream = (SkWStream*)png_get_io_ptr(png_ptr);
if (!stream->write(data, len)) {
png_error(png_ptr, "sk_write_fn cannot write to stream");
}
}
