/* pngpread.c - read a png file in push mode
*
- * libpng 1.0.1
- * For conditions of distribution and use, see copyright notice in png.h
- * Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.
- * Copyright (c) 1996, 1997 Andreas Dilger
- * Copyright (c) 1998, Glenn Randers-Pehrson
- * March 15, 1998
+ * Last changed in libpng 1.4.3 [June 26, 2010]
+ * Copyright (c) 1998-2010 Glenn Randers-Pehrson
+ * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
+ * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
+ *
+ * This code is released under the libpng license.
+ * For conditions of distribution and use, see the disclaimer
+ * and license in png.h
*/
-#define PNG_INTERNAL
+#define PNG_NO_PEDANTIC_WARNINGS
#include "png.h"
-
#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
-
-void
+#include "pngpriv.h"
+
+/* Push model modes */
+#define PNG_READ_SIG_MODE 0
+#define PNG_READ_CHUNK_MODE 1
+#define PNG_READ_IDAT_MODE 2
+#define PNG_SKIP_MODE 3
+#define PNG_READ_tEXt_MODE 4
+#define PNG_READ_zTXt_MODE 5
+#define PNG_READ_DONE_MODE 6
+#define PNG_READ_iTXt_MODE 7
+#define PNG_ERROR_MODE 8
+
+void PNGAPI
png_process_data(png_structp png_ptr, png_infop info_ptr,
png_bytep buffer, png_size_t buffer_size)
{
+ if (png_ptr == NULL || info_ptr == NULL)
+ return;
+
png_push_restore_buffer(png_ptr, buffer, buffer_size);
while (png_ptr->buffer_size)
/* What we do with the incoming data depends on what we were previously
* doing before we ran out of data...
*/
-void
+void /* PRIVATE */
png_process_some_data(png_structp png_ptr, png_infop info_ptr)
{
+ if (png_ptr == NULL)
+ return;
+
switch (png_ptr->process_mode)
{
case PNG_READ_SIG_MODE:
png_push_read_sig(png_ptr, info_ptr);
break;
}
+
case PNG_READ_CHUNK_MODE:
{
png_push_read_chunk(png_ptr, info_ptr);
break;
}
+
case PNG_READ_IDAT_MODE:
{
png_push_read_IDAT(png_ptr);
break;
}
-#if defined(PNG_READ_tEXt_SUPPORTED)
+
+#ifdef PNG_READ_tEXt_SUPPORTED
case PNG_READ_tEXt_MODE:
{
png_push_read_tEXt(png_ptr, info_ptr);
break;
}
+
#endif
-#if defined(PNG_READ_zTXt_SUPPORTED)
+#ifdef PNG_READ_zTXt_SUPPORTED
case PNG_READ_zTXt_MODE:
{
png_push_read_zTXt(png_ptr, info_ptr);
break;
}
+
+#endif
+#ifdef PNG_READ_iTXt_SUPPORTED
+ case PNG_READ_iTXt_MODE:
+ {
+ png_push_read_iTXt(png_ptr, info_ptr);
+ break;
+ }
+
#endif
case PNG_SKIP_MODE:
{
png_push_crc_finish(png_ptr);
break;
}
+
default:
{
png_ptr->buffer_size = 0;
/* Read any remaining signature bytes from the stream and compare them with
* the correct PNG signature. It is possible that this routine is called
- * with bytes already read from the signature, whether because they have been
- * checked by the calling application, or from multiple calls to this routine.
+ * with bytes already read from the signature, either because they have been
+ * checked by the calling application, or because of multiple calls to this
+ * routine.
*/
-void
+void /* PRIVATE */
png_push_read_sig(png_structp png_ptr, png_infop info_ptr)
{
png_size_t num_checked = png_ptr->sig_bytes,
num_to_check = png_ptr->buffer_size;
}
- png_push_fill_buffer(png_ptr, &(info_ptr->signature[num_checked]),
+ png_push_fill_buffer(png_ptr, &(info_ptr->signature[num_checked]),
num_to_check);
- png_ptr->sig_bytes += num_to_check;
+ png_ptr->sig_bytes = (png_byte)(png_ptr->sig_bytes + num_to_check);
if (png_sig_cmp(info_ptr->signature, num_checked, num_to_check))
{
}
}
-void
+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->flags & PNG_FLAG_HAVE_CHUNK_HEADER))
+ if (!(png_ptr->mode & PNG_HAVE_CHUNK_HEADER))
{
png_byte chunk_length[4];
}
png_push_fill_buffer(png_ptr, chunk_length, 4);
- png_ptr->push_length = png_get_uint_32(chunk_length);
+ 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->flags |= PNG_FLAG_HAVE_CHUNK_HEADER;
+ 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);
png_handle_IHDR(png_ptr, info_ptr, png_ptr->push_length);
}
- else if (!png_memcmp(png_ptr->chunk_name, png_PLTE, 4))
+
+ 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)
{
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->push_length == 0)
- return;
+ if (!(png_ptr->mode & PNG_HAVE_CHUNK_AFTER_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_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_ptr->irowbytes;
+ 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;
}
- 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)
+#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_handle_gAMA(png_ptr, info_ptr, png_ptr->push_length);
}
+
#endif
-#if defined(PNG_READ_sBIT_SUPPORTED)
+#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_handle_sBIT(png_ptr, info_ptr, png_ptr->push_length);
}
+
#endif
-#if defined(PNG_READ_cHRM_SUPPORTED)
+#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_handle_cHRM(png_ptr, info_ptr, png_ptr->push_length);
}
+
#endif
-#if defined(PNG_READ_sRGB_SUPPORTED)
+#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_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
-#if defined(PNG_READ_tRNS_SUPPORTED)
+#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_handle_tRNS(png_ptr, info_ptr, png_ptr->push_length);
}
+
#endif
-#if defined(PNG_READ_bKGD_SUPPORTED)
+#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_handle_bKGD(png_ptr, info_ptr, png_ptr->push_length);
}
+
#endif
-#if defined(PNG_READ_hIST_SUPPORTED)
+#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_handle_hIST(png_ptr, info_ptr, png_ptr->push_length);
}
+
#endif
-#if defined(PNG_READ_pHYs_SUPPORTED)
+#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_handle_pHYs(png_ptr, info_ptr, png_ptr->push_length);
}
+
#endif
-#if defined(PNG_READ_oFFs_SUPPORTED)
+#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_handle_oFFs(png_ptr, info_ptr, png_ptr->push_length);
}
#endif
-#if defined(PNG_READ_pCAL_SUPPORTED)
+
+#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_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
-#if defined(PNG_READ_tIME_SUPPORTED)
+#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_handle_tIME(png_ptr, info_ptr, png_ptr->push_length);
}
+
#endif
-#if defined(PNG_READ_tEXt_SUPPORTED)
+#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
-#if defined(PNG_READ_zTXt_SUPPORTED)
+#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->flags &= ~PNG_FLAG_HAVE_CHUNK_HEADER;
+ png_ptr->mode &= ~PNG_HAVE_CHUNK_HEADER;
}
-void
+void /* PRIVATE */
png_push_crc_skip(png_structp png_ptr, png_uint_32 skip)
{
png_ptr->process_mode = PNG_SKIP_MODE;
png_ptr->skip_length = skip;
}
-void
+void /* PRIVATE */
png_push_crc_finish(png_structp png_ptr)
{
if (png_ptr->skip_length && png_ptr->save_buffer_size)
}
}
-void
+void PNGAPI
png_push_fill_buffer(png_structp png_ptr, png_bytep buffer, png_size_t length)
{
png_bytep ptr;
+ if (png_ptr == NULL)
+ return;
+
ptr = buffer;
if (png_ptr->save_buffer_size)
{
if (length < png_ptr->current_buffer_size)
save_size = length;
+
else
save_size = png_ptr->current_buffer_size;
}
}
-void
+void /* PRIVATE */
png_push_save_buffer(png_structp png_ptr)
{
if (png_ptr->save_buffer_size)
{
if (png_ptr->save_buffer_ptr != png_ptr->save_buffer)
{
- png_size_t i;
+ png_size_t i, istop;
png_bytep sp;
png_bytep dp;
+ istop = png_ptr->save_buffer_size;
for (i = 0, sp = png_ptr->save_buffer_ptr, dp = png_ptr->save_buffer;
- i < png_ptr->save_buffer_size;
- i++, sp++, dp++)
+ i < istop; i++, sp++, dp++)
{
*dp = *sp;
}
png_size_t new_max;
png_bytep old_buffer;
+ if (png_ptr->save_buffer_size > PNG_SIZE_MAX -
+ (png_ptr->current_buffer_size + 256))
+ {
+ png_error(png_ptr, "Potential overflow of save_buffer");
+ }
+
new_max = png_ptr->save_buffer_size + png_ptr->current_buffer_size + 256;
old_buffer = png_ptr->save_buffer;
- png_ptr->save_buffer = (png_bytep)png_malloc(png_ptr,
- (png_uint_32)new_max);
+ png_ptr->save_buffer = (png_bytep)png_malloc_warn(png_ptr,
+ (png_size_t)new_max);
+ if (png_ptr->save_buffer == NULL)
+ {
+ png_free(png_ptr, old_buffer);
+ png_error(png_ptr, "Insufficient memory for save_buffer");
+ }
png_memcpy(png_ptr->save_buffer, old_buffer, png_ptr->save_buffer_size);
png_free(png_ptr, old_buffer);
png_ptr->save_buffer_max = new_max;
png_ptr->buffer_size = 0;
}
-void
+void /* PRIVATE */
png_push_restore_buffer(png_structp png_ptr, png_bytep buffer,
png_size_t buffer_length)
{
png_ptr->current_buffer_ptr = png_ptr->current_buffer;
}
-void
+void /* PRIVATE */
png_push_read_IDAT(png_structp png_ptr)
{
- if (!(png_ptr->flags & PNG_FLAG_HAVE_CHUNK_HEADER))
+ PNG_IDAT;
+ if (!(png_ptr->mode & PNG_HAVE_CHUNK_HEADER))
{
png_byte chunk_length[4];
}
png_push_fill_buffer(png_ptr, chunk_length, 4);
- png_ptr->push_length = png_get_uint_32(chunk_length);
-
+ 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->flags |= PNG_FLAG_HAVE_CHUNK_HEADER;
+ png_ptr->mode |= PNG_HAVE_CHUNK_HEADER;
if (png_memcmp(png_ptr->chunk_name, png_IDAT, 4))
{
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)
+
+ /* 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);
+
png_process_IDAT_data(png_ptr, png_ptr->save_buffer_ptr, save_size);
png_ptr->idat_size -= 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)
+
+ /* 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);
+
png_process_IDAT_data(png_ptr, png_ptr->current_buffer_ptr, save_size);
png_ptr->idat_size -= save_size;
}
png_crc_finish(png_ptr, 0);
- png_ptr->flags &= ~PNG_FLAG_HAVE_CHUNK_HEADER;
+ png_ptr->mode &= ~PNG_HAVE_CHUNK_HEADER;
+ png_ptr->mode |= PNG_AFTER_IDAT;
}
}
-void
+void /* PRIVATE */
png_process_IDAT_data(png_structp png_ptr, png_bytep buffer,
png_size_t buffer_length)
{
- int ret;
-
- if ((png_ptr->flags & PNG_FLAG_ZLIB_FINISHED) && buffer_length)
- png_error(png_ptr, "Extra compression data");
+ /* The caller checks for a non-zero buffer length. */
+ if (!(buffer_length > 0) || buffer == NULL)
+ png_error(png_ptr, "No IDAT data (internal error)");
+ /* 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;
png_ptr->zstream.avail_in = (uInt)buffer_length;
- for(;;)
+
+ /* 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_ZLIB_FINISHED))
{
- ret = inflate(&png_ptr->zstream, Z_PARTIAL_FLUSH);
- if (ret == Z_STREAM_END)
+ int ret;
+
+ /* We have data for zlib, but we must check that zlib
+ * has somewhere 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))
{
- if (png_ptr->zstream.avail_in)
- png_error(png_ptr, "Extra compressed data");
- if (!(png_ptr->zstream.avail_out))
- {
- png_push_process_row(png_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;
+ }
- png_ptr->mode |= PNG_AFTER_IDAT;
+ /* Using Z_SYNC_FLUSH here means that an unterminated
+ * LZ stream can still be handled (a stream with a missing
+ * end code), 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_ZLIB_FINISHED;
- break;
+
+ /* 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;
}
- else if (ret == Z_BUF_ERROR)
- break;
- else if (ret != Z_OK)
- png_error(png_ptr, "Decompression Error");
- if (!(png_ptr->zstream.avail_out))
+
+ /* Did inflate output any data? */
+ if (png_ptr->zstream.next_out != png_ptr->row_buf)
{
- png_push_process_row(png_ptr);
- png_ptr->zstream.avail_out = (uInt)png_ptr->irowbytes;
- 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_ZLIB_FINISHED;
+ /* 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);
}
- else
- break;
+
+ /* And check for the end of the stream. */
+ if (ret == Z_STREAM_END)
+ png_ptr->flags |= PNG_FLAG_ZLIB_FINISHED;
}
+
+ /* 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");
}
-void
+void /* PRIVATE */
png_push_process_row(png_structp png_ptr)
{
png_ptr->row_info.color_type = png_ptr->color_type;
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_ptr->row_info.width *
- (png_uint_32)png_ptr->row_info.pixel_depth + 7) >> 3);
+
+ png_ptr->row_info.rowbytes = PNG_ROWBYTES(png_ptr->row_info.pixel_depth,
+ png_ptr->row_info.width);
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_ptr->row_buf + 1, png_ptr->prev_row + 1,
+ (int)(png_ptr->row_buf[0]));
- png_memcpy_check(png_ptr, png_ptr->prev_row, png_ptr->row_buf,
- png_ptr->rowbytes + 1);
+ png_memcpy(png_ptr->prev_row, png_ptr->row_buf, png_ptr->rowbytes + 1);
- if (png_ptr->transformations)
+ if (png_ptr->transformations || (png_ptr->flags&PNG_FLAG_STRIP_ALPHA))
png_do_read_transformations(png_ptr);
-#if defined(PNG_READ_INTERLACING_SUPPORTED)
- /* blow up interlaced rows to full size */
+#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_ptr->row_buf + 1, png_ptr->pass, png_ptr->transformations);
+ */
+ png_do_read_interlace(png_ptr);
- switch (png_ptr->pass)
- {
+ 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);
+ 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;
png_push_have_row(png_ptr, png_ptr->row_buf + 1);
png_read_push_finish_row(png_ptr);
}
- if (png_ptr->pass == 2)
+
+ if (png_ptr->pass == 2) /* Skip top 4 generated rows */
{
for (i = 0; i < 4 && png_ptr->pass == 2; i++)
{
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)
+
+ if (png_ptr->pass == 4) /* Skip top two generated rows */
{
for (i = 0; i < 2 && png_ptr->pass == 4; i++)
{
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)
+
+ if (png_ptr->pass == 6) /* Skip top generated row */
{
png_push_have_row(png_ptr, NULL);
png_read_push_finish_row(png_ptr);
}
+
break;
}
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);
}
}
}
-void
+void /* PRIVATE */
png_read_push_finish_row(png_structp png_ptr)
{
+ /* Arrays to facilitate easy interlacing - use pass (0 - 6) as index */
+
+ /* Start of interlace block */
+ PNG_CONST int FARDATA png_pass_start[] = {0, 4, 0, 2, 0, 1, 0};
+
+ /* Offset to next interlace block */
+ PNG_CONST int FARDATA png_pass_inc[] = {8, 8, 4, 4, 2, 2, 1};
+
+ /* Start of interlace block in the y direction */
+ PNG_CONST int FARDATA png_pass_ystart[] = {0, 0, 4, 0, 2, 0, 1};
+
+ /* Offset to next interlace block in the y direction */
+ PNG_CONST int FARDATA png_pass_yinc[] = {8, 8, 8, 4, 4, 2, 2};
+
+ /* Height of interlace block. This is not currently used - if you need
+ * it, uncomment it here and in png.h
+ PNG_CONST int FARDATA png_pass_height[] = {8, 8, 4, 4, 2, 2, 1};
+ */
+
png_ptr->row_number++;
if (png_ptr->row_number < png_ptr->num_rows)
return;
+#ifdef PNG_READ_INTERLACING_SUPPORTED
if (png_ptr->interlaced)
{
png_ptr->row_number = 0;
- png_memset_check(png_ptr, png_ptr->prev_row, 0,
+ png_memset(png_ptr->prev_row, 0,
png_ptr->rowbytes + 1);
do
{
png_ptr->pass++;
+ if ((png_ptr->pass == 1 && png_ptr->width < 5) ||
+ (png_ptr->pass == 3 && png_ptr->width < 3) ||
+ (png_ptr->pass == 5 && png_ptr->width < 2))
+ png_ptr->pass++;
+
+ if (png_ptr->pass > 7)
+ png_ptr->pass--;
+
if (png_ptr->pass >= 7)
break;
+
png_ptr->iwidth = (png_ptr->width +
png_pass_inc[png_ptr->pass] - 1 -
png_pass_start[png_ptr->pass]) /
png_pass_inc[png_ptr->pass];
- png_ptr->irowbytes = ((png_ptr->iwidth *
- png_ptr->pixel_depth + 7) >> 3) + 1;
-
- if (!(png_ptr->transformations & PNG_INTERLACE))
- {
- png_ptr->num_rows = (png_ptr->height +
- png_pass_yinc[png_ptr->pass] - 1 -
- png_pass_ystart[png_ptr->pass]) /
- png_pass_yinc[png_ptr->pass];
- if (!(png_ptr->num_rows))
- continue;
- }
if (png_ptr->transformations & PNG_INTERLACE)
break;
- } while (png_ptr->iwidth == 0);
+
+ png_ptr->num_rows = (png_ptr->height +
+ png_pass_yinc[png_ptr->pass] - 1 -
+ png_pass_ystart[png_ptr->pass]) /
+ png_pass_yinc[png_ptr->pass];
+
+ } while (png_ptr->iwidth == 0 || png_ptr->num_rows == 0);
}
+#endif /* PNG_READ_INTERLACING_SUPPORTED */
}
-#if defined(PNG_READ_tEXt_SUPPORTED)
-void
-png_push_handle_tEXt(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
+#ifdef PNG_READ_tEXt_SUPPORTED
+void /* PRIVATE */
+png_push_handle_tEXt(png_structp png_ptr, png_infop info_ptr, png_uint_32
+ length)
{
- if (png_ptr->mode == PNG_BEFORE_IHDR || png_ptr->mode & PNG_HAVE_IEND)
+ if (!(png_ptr->mode & PNG_HAVE_IHDR) || (png_ptr->mode & PNG_HAVE_IEND))
{
png_error(png_ptr, "Out of place tEXt");
- /* to quiet some compiler warnings */
- if(info_ptr == NULL) return;
+ info_ptr = info_ptr; /* To quiet some compiler warnings */
}
#ifdef PNG_MAX_MALLOC_64K
png_ptr->skip_length = 0; /* This may not be necessary */
- if (length > (png_uint_32)65535L) /* Can't hold the entire string in memory */
+ if (length > (png_uint_32)65535L) /* Can't hold entire string in memory */
{
png_warning(png_ptr, "tEXt chunk too large to fit in memory");
png_ptr->skip_length = length - (png_uint_32)65535L;
}
#endif
- png_ptr->current_text = (png_charp)png_malloc(png_ptr,
- (png_uint_32)(length+1));
+ png_ptr->current_text = (png_charp)png_malloc(png_ptr,
+ (png_size_t)(length + 1));
png_ptr->current_text[length] = '\0';
png_ptr->current_text_ptr = png_ptr->current_text;
png_ptr->current_text_size = (png_size_t)length;
png_ptr->process_mode = PNG_READ_tEXt_MODE;
}
-void
+void /* PRIVATE */
png_push_read_tEXt(png_structp png_ptr, png_infop info_ptr)
{
if (png_ptr->buffer_size && png_ptr->current_text_left)
if (png_ptr->buffer_size < png_ptr->current_text_left)
text_size = png_ptr->buffer_size;
+
else
text_size = png_ptr->current_text_left;
+
png_crc_read(png_ptr, (png_bytep)png_ptr->current_text_ptr, text_size);
png_ptr->current_text_left -= text_size;
png_ptr->current_text_ptr += text_size;
png_textp text_ptr;
png_charp text;
png_charp key;
+ int ret;
if (png_ptr->buffer_size < 4)
{
png_push_crc_finish(png_ptr);
-#if defined(PNG_MAX_MALLOC_64K)
+#ifdef PNG_MAX_MALLOC_64K
if (png_ptr->skip_length)
return;
#endif
key = png_ptr->current_text;
- png_ptr->current_text = 0;
for (text = key; *text; text++)
- /* empty loop */ ;
+ /* Empty loop */ ;
- if (text != key + png_ptr->current_text_size)
+ if (text < key + png_ptr->current_text_size)
text++;
- text_ptr = (png_textp)png_malloc(png_ptr, (png_uint_32)sizeof(png_text));
+ text_ptr = (png_textp)png_malloc(png_ptr,
+ png_sizeof(png_text));
text_ptr->compression = PNG_TEXT_COMPRESSION_NONE;
text_ptr->key = key;
+#ifdef PNG_iTXt_SUPPORTED
+ text_ptr->lang = NULL;
+ text_ptr->lang_key = NULL;
+#endif
text_ptr->text = text;
- png_set_text(png_ptr, info_ptr, text_ptr, 1);
+ ret = png_set_text_2(png_ptr, info_ptr, text_ptr, 1);
+ png_free(png_ptr, key);
png_free(png_ptr, text_ptr);
+ png_ptr->current_text = NULL;
+
+ if (ret)
+ png_warning(png_ptr, "Insufficient memory to store text chunk");
}
}
#endif
-#if defined(PNG_READ_zTXt_SUPPORTED)
-void
-png_push_handle_zTXt(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
+#ifdef PNG_READ_zTXt_SUPPORTED
+void /* PRIVATE */
+png_push_handle_zTXt(png_structp png_ptr, png_infop info_ptr, png_uint_32
+ length)
{
- if (png_ptr->mode == PNG_BEFORE_IHDR || png_ptr->mode & PNG_HAVE_IEND)
+ if (!(png_ptr->mode & PNG_HAVE_IHDR) || (png_ptr->mode & PNG_HAVE_IEND))
{
png_error(png_ptr, "Out of place zTXt");
- /* to quiet some compiler warnings */
- if(info_ptr == NULL) return;
+ info_ptr = info_ptr; /* To quiet some compiler warnings */
}
#ifdef PNG_MAX_MALLOC_64K
#endif
png_ptr->current_text = (png_charp)png_malloc(png_ptr,
- (png_uint_32)(length+1));
+ (png_size_t)(length + 1));
png_ptr->current_text[length] = '\0';
png_ptr->current_text_ptr = png_ptr->current_text;
png_ptr->current_text_size = (png_size_t)length;
png_ptr->process_mode = PNG_READ_zTXt_MODE;
}
-void
+void /* PRIVATE */
png_push_read_zTXt(png_structp png_ptr, png_infop info_ptr)
{
if (png_ptr->buffer_size && png_ptr->current_text_left)
if (png_ptr->buffer_size < (png_uint_32)png_ptr->current_text_left)
text_size = png_ptr->buffer_size;
+
else
text_size = png_ptr->current_text_left;
+
png_crc_read(png_ptr, (png_bytep)png_ptr->current_text_ptr, text_size);
png_ptr->current_text_left -= text_size;
png_ptr->current_text_ptr += text_size;
png_push_crc_finish(png_ptr);
key = png_ptr->current_text;
- png_ptr->current_text = 0;
for (text = key; *text; text++)
- /* empty loop */ ;
+ /* Empty loop */ ;
/* zTXt can't have zero text */
- if (text == key + png_ptr->current_text_size)
+ if (text >= key + png_ptr->current_text_size)
{
+ png_ptr->current_text = NULL;
png_free(png_ptr, key);
return;
}
text++;
- if (*text != PNG_TEXT_COMPRESSION_zTXt) /* check compression byte */
+ if (*text != PNG_TEXT_COMPRESSION_zTXt) /* Check compression byte */
{
+ png_ptr->current_text = NULL;
png_free(png_ptr, key);
return;
}
{
inflateReset(&png_ptr->zstream);
png_ptr->zstream.avail_in = 0;
+ png_ptr->current_text = NULL;
png_free(png_ptr, key);
png_free(png_ptr, text);
return;
if (text == NULL)
{
text = (png_charp)png_malloc(png_ptr,
- (png_uint_32)(png_ptr->zbuf_size - png_ptr->zstream.avail_out +
- key_size + 1));
+ (png_ptr->zbuf_size
+ - png_ptr->zstream.avail_out + key_size + 1));
+
png_memcpy(text + key_size, png_ptr->zbuf,
png_ptr->zbuf_size - png_ptr->zstream.avail_out);
+
png_memcpy(text, key, key_size);
+
text_size = key_size + png_ptr->zbuf_size -
png_ptr->zstream.avail_out;
+
*(text + text_size) = '\0';
}
else
tmp = text;
text = (png_charp)png_malloc(png_ptr, text_size +
- (png_uint_32)(png_ptr->zbuf_size - png_ptr->zstream.avail_out
- + 1));
+ (png_ptr->zbuf_size
+ - png_ptr->zstream.avail_out + 1));
+
png_memcpy(text, tmp, text_size);
png_free(png_ptr, tmp);
+
png_memcpy(text + text_size, png_ptr->zbuf,
png_ptr->zbuf_size - png_ptr->zstream.avail_out);
+
text_size += png_ptr->zbuf_size - png_ptr->zstream.avail_out;
*(text + text_size) = '\0';
}
if (ret != Z_STREAM_END)
{
+ png_ptr->current_text = NULL;
png_free(png_ptr, key);
png_free(png_ptr, text);
return;
}
+ png_ptr->current_text = NULL;
png_free(png_ptr, key);
key = text;
text += key_size;
- text_ptr = (png_textp)png_malloc(png_ptr, (png_uint_32)sizeof(png_text));
+ text_ptr = (png_textp)png_malloc(png_ptr,
+ png_sizeof(png_text));
text_ptr->compression = PNG_TEXT_COMPRESSION_zTXt;
text_ptr->key = key;
+#ifdef PNG_iTXt_SUPPORTED
+ text_ptr->lang = NULL;
+ text_ptr->lang_key = NULL;
+#endif
+ text_ptr->text = text;
+
+ ret = png_set_text_2(png_ptr, info_ptr, text_ptr, 1);
+
+ png_free(png_ptr, key);
+ png_free(png_ptr, text_ptr);
+
+ if (ret)
+ png_warning(png_ptr, "Insufficient memory to store text chunk");
+ }
+}
+#endif
+
+#ifdef PNG_READ_iTXt_SUPPORTED
+void /* PRIVATE */
+png_push_handle_iTXt(png_structp png_ptr, png_infop info_ptr, png_uint_32
+ length)
+{
+ if (!(png_ptr->mode & PNG_HAVE_IHDR) || (png_ptr->mode & PNG_HAVE_IEND))
+ {
+ png_error(png_ptr, "Out of place iTXt");
+ info_ptr = info_ptr; /* To quiet some compiler warnings */
+ }
+
+#ifdef PNG_MAX_MALLOC_64K
+ png_ptr->skip_length = 0; /* This may not be necessary */
+
+ if (length > (png_uint_32)65535L) /* Can't hold entire string in memory */
+ {
+ png_warning(png_ptr, "iTXt chunk too large to fit in memory");
+ png_ptr->skip_length = length - (png_uint_32)65535L;
+ length = (png_uint_32)65535L;
+ }
+#endif
+
+ png_ptr->current_text = (png_charp)png_malloc(png_ptr,
+ (png_size_t)(length + 1));
+ png_ptr->current_text[length] = '\0';
+ png_ptr->current_text_ptr = png_ptr->current_text;
+ png_ptr->current_text_size = (png_size_t)length;
+ png_ptr->current_text_left = (png_size_t)length;
+ png_ptr->process_mode = PNG_READ_iTXt_MODE;
+}
+
+void /* PRIVATE */
+png_push_read_iTXt(png_structp png_ptr, png_infop info_ptr)
+{
+
+ if (png_ptr->buffer_size && png_ptr->current_text_left)
+ {
+ png_size_t text_size;
+
+ if (png_ptr->buffer_size < png_ptr->current_text_left)
+ text_size = png_ptr->buffer_size;
+
+ else
+ text_size = png_ptr->current_text_left;
+
+ png_crc_read(png_ptr, (png_bytep)png_ptr->current_text_ptr, text_size);
+ png_ptr->current_text_left -= text_size;
+ png_ptr->current_text_ptr += text_size;
+ }
+ if (!(png_ptr->current_text_left))
+ {
+ png_textp text_ptr;
+ png_charp key;
+ int comp_flag;
+ png_charp lang;
+ png_charp lang_key;
+ png_charp text;
+ int ret;
+
+ if (png_ptr->buffer_size < 4)
+ {
+ png_push_save_buffer(png_ptr);
+ return;
+ }
+
+ png_push_crc_finish(png_ptr);
+
+#ifdef PNG_MAX_MALLOC_64K
+ if (png_ptr->skip_length)
+ return;
+#endif
+
+ key = png_ptr->current_text;
+
+ for (lang = key; *lang; lang++)
+ /* Empty loop */ ;
+
+ if (lang < key + png_ptr->current_text_size - 3)
+ lang++;
+
+ comp_flag = *lang++;
+ lang++; /* Skip comp_type, always zero */
+
+ for (lang_key = lang; *lang_key; lang_key++)
+ /* Empty loop */ ;
+
+ lang_key++; /* Skip NUL separator */
+
+ text=lang_key;
+
+ if (lang_key < key + png_ptr->current_text_size - 1)
+ {
+ for (; *text; text++)
+ /* Empty loop */ ;
+ }
+
+ if (text < key + png_ptr->current_text_size)
+ text++;
+
+ text_ptr = (png_textp)png_malloc(png_ptr,
+ png_sizeof(png_text));
+
+ text_ptr->compression = comp_flag + 2;
+ text_ptr->key = key;
+ text_ptr->lang = lang;
+ text_ptr->lang_key = lang_key;
text_ptr->text = text;
+ text_ptr->text_length = 0;
+ text_ptr->itxt_length = png_strlen(text);
+
+ ret = png_set_text_2(png_ptr, info_ptr, text_ptr, 1);
- png_set_text(png_ptr, info_ptr, text_ptr, 1);
+ png_ptr->current_text = NULL;
png_free(png_ptr, text_ptr);
+ if (ret)
+ png_warning(png_ptr, "Insufficient memory to store iTXt chunk");
}
}
#endif
/* This function is called when we haven't found a handler for this
- * chunk. In the future we will have code here which can handle
- * user-defined callback functions for unknown chunks before they are
- * ignored or cause an error. If there isn't a problem with the
- * chunk itself (ie a bad chunk name or a critical chunk), the chunk
- * is (currently) silently ignored.
+ * chunk. If there isn't a problem with the chunk itself (ie a bad chunk
+ * name or a critical chunk), the chunk is (currently) silently ignored.
*/
-void
-png_push_handle_unknown(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
+void /* PRIVATE */
+png_push_handle_unknown(png_structp png_ptr, png_infop info_ptr, png_uint_32
+ length)
{
- png_check_chunk_name(png_ptr, png_ptr->chunk_name);
+ png_uint_32 skip = 0;
if (!(png_ptr->chunk_name[0] & 0x20))
{
- png_chunk_error(png_ptr, "unknown critical chunk");
- /* to quiet some compiler warnings */
- if(info_ptr == NULL) return;
+#ifdef PNG_READ_UNKNOWN_CHUNKS_SUPPORTED
+ if (png_handle_as_unknown(png_ptr, png_ptr->chunk_name) !=
+ PNG_HANDLE_CHUNK_ALWAYS
+#ifdef PNG_READ_USER_CHUNKS_SUPPORTED
+ && png_ptr->read_user_chunk_fn == NULL
+#endif
+ )
+#endif
+ png_chunk_error(png_ptr, "unknown critical chunk");
+
+ info_ptr = info_ptr; /* To quiet some compiler warnings */
}
- png_push_crc_skip(png_ptr, length);
+#ifdef PNG_READ_UNKNOWN_CHUNKS_SUPPORTED
+ if (png_ptr->flags & PNG_FLAG_KEEP_UNKNOWN_CHUNKS)
+ {
+#ifdef PNG_MAX_MALLOC_64K
+ if (length > (png_uint_32)65535L)
+ {
+ png_warning(png_ptr, "unknown chunk too large to fit in memory");
+ skip = length - (png_uint_32)65535L;
+ length = (png_uint_32)65535L;
+ }
+#endif
+ png_memcpy((png_charp)png_ptr->unknown_chunk.name,
+ (png_charp)png_ptr->chunk_name,
+ png_sizeof(png_ptr->unknown_chunk.name));
+ png_ptr->unknown_chunk.name[png_sizeof(png_ptr->unknown_chunk.name) - 1]
+ = '\0';
+
+ png_ptr->unknown_chunk.size = (png_size_t)length;
+
+ if (length == 0)
+ png_ptr->unknown_chunk.data = NULL;
+
+ else
+ {
+ png_ptr->unknown_chunk.data = (png_bytep)png_malloc(png_ptr,
+ (png_size_t)length);
+ png_crc_read(png_ptr, (png_bytep)png_ptr->unknown_chunk.data, length);
+ }
+
+#ifdef PNG_READ_USER_CHUNKS_SUPPORTED
+ if (png_ptr->read_user_chunk_fn != NULL)
+ {
+ /* Callback to user unknown chunk handler */
+ int ret;
+ ret = (*(png_ptr->read_user_chunk_fn))
+ (png_ptr, &png_ptr->unknown_chunk);
+
+ if (ret < 0)
+ png_chunk_error(png_ptr, "error in user chunk");
+
+ if (ret == 0)
+ {
+ if (!(png_ptr->chunk_name[0] & 0x20))
+ if (png_handle_as_unknown(png_ptr, png_ptr->chunk_name) !=
+ PNG_HANDLE_CHUNK_ALWAYS)
+ png_chunk_error(png_ptr, "unknown critical chunk");
+ png_set_unknown_chunks(png_ptr, info_ptr,
+ &png_ptr->unknown_chunk, 1);
+ }
+ }
+
+ else
+#endif
+ png_set_unknown_chunks(png_ptr, info_ptr, &png_ptr->unknown_chunk, 1);
+ png_free(png_ptr, png_ptr->unknown_chunk.data);
+ png_ptr->unknown_chunk.data = NULL;
+ }
+
+ else
+#endif
+ skip=length;
+ png_push_crc_skip(png_ptr, skip);
}
-void
+void /* PRIVATE */
png_push_have_info(png_structp png_ptr, png_infop info_ptr)
{
if (png_ptr->info_fn != NULL)
(*(png_ptr->info_fn))(png_ptr, info_ptr);
}
-void
+void /* PRIVATE */
png_push_have_end(png_structp png_ptr, png_infop info_ptr)
{
if (png_ptr->end_fn != NULL)
(*(png_ptr->end_fn))(png_ptr, info_ptr);
}
-void
+void /* PRIVATE */
png_push_have_row(png_structp png_ptr, png_bytep row)
{
if (png_ptr->row_fn != NULL)
(int)png_ptr->pass);
}
-void
+void PNGAPI
png_progressive_combine_row (png_structp png_ptr,
png_bytep old_row, png_bytep new_row)
{
- if (new_row != NULL)
+ PNG_CONST int FARDATA png_pass_dsp_mask[7] =
+ {0xff, 0x0f, 0xff, 0x33, 0xff, 0x55, 0xff};
+
+ if (png_ptr == NULL)
+ return;
+
+ if (new_row != NULL) /* new_row must == png_ptr->row_buf here. */
png_combine_row(png_ptr, old_row, png_pass_dsp_mask[png_ptr->pass]);
}
-void
+void PNGAPI
png_set_progressive_read_fn(png_structp png_ptr, png_voidp progressive_ptr,
png_progressive_info_ptr info_fn, png_progressive_row_ptr row_fn,
png_progressive_end_ptr end_fn)
{
+ if (png_ptr == NULL)
+ return;
+
png_ptr->info_fn = info_fn;
png_ptr->row_fn = row_fn;
png_ptr->end_fn = end_fn;
png_set_read_fn(png_ptr, progressive_ptr, png_push_fill_buffer);
}
-png_voidp
+png_voidp PNGAPI
png_get_progressive_ptr(png_structp png_ptr)
{
+ if (png_ptr == NULL)
+ return (NULL);
+
return png_ptr->io_ptr;
}
-
#endif /* PNG_PROGRESSIVE_READ_SUPPORTED */
-