mewin/libpng
1
0
Fork 0
mirror of https://git.code.sf.net/p/libpng/code.git synced 2025-07-10 18:04:09 +02:00
Code Issues Projects Releases Wiki Activity

[master] Imported from libpng-1.6.18.tar

Browse Source
This commit is contained in:
Glenn Randers-Pehrson
2015-07-22 22:36:43 -05:00
parent 2b667e4923
commit 287fb89248
54 changed files with 3139 additions and 1878 deletions
Download Patch File Download Diff File Expand all files Collapse all files

111
pngpread.c
View File

@@ -1,7 +1,7 @@
/* pngpread.c - read a png file in push mode
*
* Last changed in libpng 1.6.17 [March 26, 2015]
* Last changed in libpng 1.6.18 [July 23, 2015]
* Copyright (c) 1998-2015 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.)
@@ -19,7 +19,6 @@
#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
@@ -78,32 +77,14 @@ png_process_data_pause(png_structrp png_ptr, int save)
png_uint_32 PNGAPI
png_process_data_skip(png_structrp png_ptr)
{
png_uint_32 remaining = 0;
if (png_ptr != NULL && png_ptr->process_mode == PNG_SKIP_MODE &&
png_ptr->skip_length > 0)
{
/* At the end of png_process_data the buffer size must be 0 (see the loop
* above) so we can detect a broken call here:
*/
if (png_ptr->buffer_size != 0)
png_error(png_ptr,
"png_process_data_skip called inside png_process_data");
/* If is impossible for there to be a saved buffer at this point -
* otherwise we could not be in SKIP mode. This will also happen if
* png_process_skip is called inside png_process_data (but only very
* rarely.)
*/
if (png_ptr->save_buffer_size != 0)
png_error(png_ptr, "png_process_data_skip called with saved data");
remaining = png_ptr->skip_length;
png_ptr->skip_length = 0;
png_ptr->process_mode = PNG_READ_CHUNK_MODE;
}
return remaining;
/* TODO: Deprecate and remove this API.
* Somewhere the implementation of this seems to have been lost,
* or abandoned. It was only to support some internal back-door access
* to png_struct) in libpng-1.4.x.
*/
png_app_warning(png_ptr,
"png_process_data_skip is not implemented in any current version of libpng");
return 0;
}
/* What we do with the incoming data depends on what we were previously
@@ -135,12 +116,6 @@ png_process_some_data(png_structrp png_ptr, png_inforp info_ptr)
break;
}
case PNG_SKIP_MODE:
{
png_push_crc_finish(png_ptr);
break;
}
default:
{
png_ptr->buffer_size = 0;
@@ -159,7 +134,7 @@ void /* PRIVATE */
png_push_read_sig(png_structrp png_ptr, png_inforp info_ptr)
{
png_size_t num_checked = png_ptr->sig_bytes, /* SAFE, does not exceed 8 */
num_to_check = 8 - num_checked;
num_to_check = 8 - num_checked;
if (png_ptr->buffer_size < num_to_check)
{
@@ -439,69 +414,6 @@ png_push_read_chunk(png_structrp png_ptr, png_inforp info_ptr)
png_ptr->mode &= ~PNG_HAVE_CHUNK_HEADER;
}
void /* PRIVATE */
png_push_crc_skip(png_structrp png_ptr, png_uint_32 skip)
{
png_ptr->process_mode = PNG_SKIP_MODE;
png_ptr->skip_length = skip;
}
void /* PRIVATE */
png_push_crc_finish(png_structrp png_ptr)
{
if (png_ptr->skip_length != 0 && png_ptr->save_buffer_size != 0)
{
png_size_t save_size = png_ptr->save_buffer_size;
png_uint_32 skip_length = png_ptr->skip_length;
/* We want the smaller of 'skip_length' and 'save_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 (skip_length < save_size)
save_size = (png_size_t)skip_length;
else
skip_length = (png_uint_32)save_size;
png_calculate_crc(png_ptr, png_ptr->save_buffer_ptr, save_size);
png_ptr->skip_length -= skip_length;
png_ptr->buffer_size -= save_size;
png_ptr->save_buffer_size -= save_size;
png_ptr->save_buffer_ptr += save_size;
}
if (png_ptr->skip_length != 0 && png_ptr->current_buffer_size != 0)
{
png_size_t save_size = png_ptr->current_buffer_size;
png_uint_32 skip_length = png_ptr->skip_length;
/* We want the smaller of 'skip_length' and 'current_buffer_size', here,
* the same problem exists as above and the same solution.
*/
if (skip_length < save_size)
save_size = (png_size_t)skip_length;
else
skip_length = (png_uint_32)save_size;
png_calculate_crc(png_ptr, png_ptr->current_buffer_ptr, save_size);
png_ptr->skip_length -= skip_length;
png_ptr->buffer_size -= save_size;
png_ptr->current_buffer_size -= save_size;
png_ptr->current_buffer_ptr += save_size;
}
if (png_ptr->skip_length == 0)
{
PNG_PUSH_SAVE_BUFFER_IF_LT(4)
png_crc_finish(png_ptr, 0);
png_ptr->process_mode = PNG_READ_CHUNK_MODE;
}
}
void PNGCBAPI
png_push_fill_buffer(png_structp png_ptr, png_bytep buffer, png_size_t length)
{
@@ -584,13 +496,11 @@ png_push_save_buffer(png_structrp png_ptr)
if (png_ptr->save_buffer == NULL)
{
png_free(png_ptr, old_buffer);
old_buffer = NULL;
png_error(png_ptr, "Insufficient memory for save_buffer");
}
memcpy(png_ptr->save_buffer, old_buffer, png_ptr->save_buffer_size);
png_free(png_ptr, old_buffer);
old_buffer = NULL;
png_ptr->save_buffer_max = new_max;
}
if (png_ptr->current_buffer_size)
@@ -696,6 +606,7 @@ png_push_read_IDAT(png_structrp png_ptr)
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)