/* 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_debug(1, "in png_read_end");
if (png_ptr == NULL)
return;
png_crc_finish(png_ptr, 0); /* Finish off CRC from last IDAT chunk */
do
{
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;
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))
{
if ((length > 0) || (png_ptr->mode & PNG_HAVE_CHUNK_AFTER_IDAT))
png_benign_error(png_ptr, "Too many IDATs found");
}
png_handle_unknown(png_ptr, info_ptr, length);
if (!png_memcmp(chunk_name, png_PLTE, 4))
png_ptr->mode |= PNG_HAVE_PLTE;
}
#endif
else if (!png_memcmp(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_HAVE_CHUNK_AFTER_IDAT))
png_benign_error(png_ptr, "Too many IDATs found");
png_crc_finish(png_ptr, length);
}
else if (!png_memcmp(chunk_name, png_PLTE, 4))
png_handle_PLTE(png_ptr, info_ptr, length);
#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);
} while (!(png_ptr->mode & PNG_HAVE_IEND));
}
void PNGAPI
png_set_iCCP(png_const_structrp png_ptr, png_inforp info_ptr,
png_const_charp name, int compression_type,
png_const_bytep profile, png_uint_32 proflen)
{
png_charp new_iccp_name;
png_bytep new_iccp_profile;
png_size_t length;
png_debug1(1, "in %s storage function", "iCCP");
if (png_ptr == NULL || info_ptr == NULL || name == NULL || profile == NULL)
return;
if (compression_type != PNG_COMPRESSION_TYPE_BASE)
png_app_error(png_ptr, "Invalid iCCP compression method");
/* Set the colorspace first because this validates the profile; do not
* override previously set app cHRM or gAMA here (because likely as not the
* application knows better than libpng what the correct values are.) Pass
* the info_ptr color_type field to png_colorspace_set_ICC because in the
* write case it has not yet been stored in png_ptr.
*/
{
int result = png_colorspace_set_ICC(png_ptr, &info_ptr->colorspace, name,
proflen, profile, info_ptr->color_type);
png_colorspace_sync_info(png_ptr, info_ptr);
/* Don't do any of the copying if the profile was bad, or inconsistent. */
if (result == 0)
return;
/* But do write the gAMA and cHRM chunks from the profile. */
info_ptr->colorspace.flags |=
PNG_COLORSPACE_FROM_gAMA|PNG_COLORSPACE_FROM_cHRM;
}
length = strlen(name)+1;
new_iccp_name = png_voidcast(png_charp, png_malloc_warn(png_ptr, length));
if (new_iccp_name == NULL)
{
png_benign_error(png_ptr, "Insufficient memory to process iCCP chunk");
return;
}
memcpy(new_iccp_name, name, length);
new_iccp_profile = png_voidcast(png_bytep,
png_malloc_warn(png_ptr, proflen));
if (new_iccp_profile == NULL)
{
png_free(png_ptr, new_iccp_name);
png_benign_error(png_ptr,
"Insufficient memory to process iCCP profile");
return;
}
memcpy(new_iccp_profile, profile, proflen);
png_free_data(png_ptr, info_ptr, PNG_FREE_ICCP, 0);
info_ptr->iccp_proflen = proflen;
info_ptr->iccp_name = new_iccp_name;
info_ptr->iccp_profile = new_iccp_profile;
info_ptr->free_me |= PNG_FREE_ICCP;
info_ptr->valid |= PNG_INFO_iCCP;
}
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;
default:
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);
}
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;
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)
{
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
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_chunk(png_structp png_ptr, png_infop info_ptr)
{
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_sRGB_SUPPORTED
PNG_sRGB;
#endif
#ifdef PNG_READ_sPLT_SUPPORTED
PNG_sPLT;
#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
/* 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_check_chunk_name(png_ptr, png_ptr->chunk_name);
png_ptr->mode |= PNG_HAVE_CHUNK_HEADER;
}
if (!png_memcmp(png_ptr->chunk_name, png_IDAT, 4))
if (png_ptr->mode & PNG_AFTER_IDAT)
png_ptr->mode |= PNG_HAVE_CHUNK_AFTER_IDAT;
if (!png_memcmp(png_ptr->chunk_name, png_IHDR, 4))
{
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 (!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_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->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_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
#ifdef 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
#ifdef 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
#ifdef 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
#ifdef 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
#ifdef 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
#ifdef 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
#ifdef 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
#ifdef 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
#ifdef 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
#ifdef 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
#ifdef 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
#ifdef 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
#ifdef 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
#ifdef 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
#ifdef 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
#ifdef 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_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) == 0)
{
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 = PNG_INFLATE(png_ptr, 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
{
if (ret == Z_DATA_ERROR)
png_benign_error(png_ptr, "IDAT: ADLER32 checksum mismatch");
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");
}
/* Writes the end of the PNG file. If you don't want to write comments or
* time information, you can pass NULL for info. If you already wrote these
* in png_write_info(), do not write them again here. If you have long
* comments, I suggest writing them here, and compressing them.
*/
void PNGAPI
png_write_end(png_structp png_ptr, png_infop info_ptr)
{
png_debug(1, "in png_write_end");
if (png_ptr == NULL)
return;
if (!(png_ptr->mode & PNG_HAVE_IDAT))
png_error(png_ptr, "No IDATs written into file");
#ifdef PNG_WRITE_CHECK_FOR_INVALID_INDEX_SUPPORTED
if (png_ptr->num_palette_max > png_ptr->num_palette)
png_benign_error(png_ptr, "Wrote palette index exceeding num_palette");
#endif
/* See if user wants us to write information chunks */
if (info_ptr != NULL)
{
#ifdef PNG_WRITE_TEXT_SUPPORTED
int i; /* local index variable */
#endif
#ifdef PNG_WRITE_tIME_SUPPORTED
/* Check to see if user has supplied a time chunk */
if ((info_ptr->valid & PNG_INFO_tIME) &&
!(png_ptr->mode & PNG_WROTE_tIME))
png_write_tIME(png_ptr, &(info_ptr->mod_time));
#endif
#ifdef PNG_WRITE_TEXT_SUPPORTED
/* Loop through comment chunks */
for (i = 0; i < info_ptr->num_text; i++)
{
png_debug2(2, "Writing trailer text chunk %d, type %d", i,
info_ptr->text[i].compression);
/* An internationalized chunk? */
if (info_ptr->text[i].compression > 0)
{
#ifdef PNG_WRITE_iTXt_SUPPORTED
/* Write international chunk */
png_write_iTXt(png_ptr,
info_ptr->text[i].compression,
info_ptr->text[i].key,
info_ptr->text[i].lang,
info_ptr->text[i].lang_key,
info_ptr->text[i].text);
/* Mark this chunk as written */
info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_NONE_WR;
#else
png_warning(png_ptr, "Unable to write international text");
#endif
}
else if (info_ptr->text[i].compression >= PNG_TEXT_COMPRESSION_zTXt)
{
#ifdef PNG_WRITE_zTXt_SUPPORTED
/* Write compressed chunk */
png_write_zTXt(png_ptr, info_ptr->text[i].key,
info_ptr->text[i].text, 0,
info_ptr->text[i].compression);
/* Mark this chunk as written */
info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_zTXt_WR;
#else
png_warning(png_ptr, "Unable to write compressed text");
#endif
}
else if (info_ptr->text[i].compression == PNG_TEXT_COMPRESSION_NONE)
{
#ifdef PNG_WRITE_tEXt_SUPPORTED
/* Write uncompressed chunk */
png_write_tEXt(png_ptr, info_ptr->text[i].key,
info_ptr->text[i].text, 0);
/* Mark this chunk as written */
info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_NONE_WR;
#else
png_warning(png_ptr, "Unable to write uncompressed text");
#endif
}
}
#endif
#ifdef PNG_WRITE_UNKNOWN_CHUNKS_SUPPORTED
if (info_ptr->unknown_chunks_num)
{
png_unknown_chunk *up;
png_debug(5, "writing extra chunks");
for (up = info_ptr->unknown_chunks;
up < info_ptr->unknown_chunks + info_ptr->unknown_chunks_num;
up++)
{
int keep = png_handle_as_unknown(png_ptr, up->name);
if (keep != PNG_HANDLE_CHUNK_NEVER &&
up->location &&
(up->location & PNG_AFTER_IDAT) &&
((up->name[3] & 0x20) || keep == PNG_HANDLE_CHUNK_ALWAYS ||
(png_ptr->flags & PNG_FLAG_KEEP_UNSAFE_CHUNKS)))
{
png_write_chunk(png_ptr, up->name, up->data, up->size);
}
}
}
#endif
}
png_ptr->mode |= PNG_AFTER_IDAT;
/* Write end of PNG file */
png_write_IEND(png_ptr);
/* This flush, added in libpng-1.0.8, removed from libpng-1.0.9beta03,
* and restored again in libpng-1.2.30, may cause some applications that
* do not set png_ptr->output_flush_fn to crash. If your application
* experiences a problem, please try building libpng with
* PNG_WRITE_FLUSH_AFTER_IEND_SUPPORTED defined, and report the event to
* png-mng-implement at lists.sf.net .
*/
#ifdef PNG_WRITE_FLUSH_SUPPORTED
# ifdef PNG_WRITE_FLUSH_AFTER_IEND_SUPPORTED
png_flush(png_ptr);
# endif
#endif
}
void /* PRIVATE */
png_push_read_chunk(png_structrp png_ptr, png_inforp info_ptr)
{
png_uint_32 chunk_name;
#ifdef PNG_SET_UNKNOWN_CHUNKS_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;
#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_push_crc_skip(png_ptr, png_ptr->push_length);
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_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)
{
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_push_crc_skip(png_ptr, png_ptr->push_length);
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)
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;
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_SET_UNKNOWN_CHUNKS_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)
{
#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)
{
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
#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
{
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;
}
