Fix inconsistent handling of invalid zlib data

In libpng 1.6 zlib initialization was changed to use the window size in the zlib
stream, not a fixed value.  This causes some invalid images, ones where CINFO is
too large, to display 'correctly' if the rest of the data is valid.  This
provides a work-round for zlib versions where the error arises (ones that
support the API change to use the window size in the stream).

Signed-off-by: John Bowler <jbowler@acm.org>
This commit is contained in:
John Bowler
2015-11-27 23:57:39 -08:00
parent 87049cbf84
commit 28a1cdfc2e
4 changed files with 46 additions and 4 deletions

View File

@@ -662,7 +662,7 @@ png_process_IDAT_data(png_structrp png_ptr, png_bytep buffer,
* 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);
ret = PNG_INFLATE(png_ptr, Z_SYNC_FLUSH);
/* Check for any failure before proceeding. */
if (ret != Z_OK && ret != Z_STREAM_END)