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

De-volatilize the internal implementation of png_safe_execute

Browse Source 
`png_safe_execute` called `setjmp` in a context where the result was
undefined (an assignment statement). This corrects the code and removes
volatile statements that were introduced previously to quell warnings
from earlier versions of GCC.

Co-authored-by: John Bowler <jbowler@acm.org>
This commit is contained in:
Cosmin Truta 2024-01-17 18:06:47 +02:00
parent 7dacc4d5aa
commit 2a4f0f5aee
1 changed files with 10 additions and 16 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

26
pngerror.c
View File

@ -933,31 +933,25 @@ png_safe_warning(png_structp png_nonconst_ptr, png_const_charp warning_message)
#endif #endif
int /* PRIVATE */ int /* PRIVATE */
png_safe_execute(png_imagep image_in, int (*function)(png_voidp), png_voidp arg) png_safe_execute(png_imagep image, int (*function)(png_voidp), png_voidp arg)
{ {
volatile png_imagep image = image_in; png_voidp saved_error_buf = image->opaque->error_buf;
volatile int result;
volatile png_voidp saved_error_buf;
jmp_buf safe_jmpbuf; jmp_buf safe_jmpbuf;
int result;
/* Safely execute function(arg) with png_error returning to this function. */ /* Safely execute function(arg), with png_error returning back here. */
saved_error_buf = image->opaque->error_buf; if (setjmp(safe_jmpbuf) == 0)
result = setjmp(safe_jmpbuf) == 0;
if (result != 0)
{ {
image->opaque->error_buf = safe_jmpbuf; image->opaque->error_buf = safe_jmpbuf;
result = function(arg); result = function(arg);
image->opaque->error_buf = saved_error_buf;
return result;
} }
/* On png_error, return via longjmp, pop the jmpbuf, and free the image. */
image->opaque->error_buf = saved_error_buf; image->opaque->error_buf = saved_error_buf;
png_image_free(image);
/* And do the cleanup prior to any failure return. */ return 0;
if (result == 0)
png_image_free(image);
return result;
} }
#endif /* SIMPLIFIED READ || SIMPLIFIED_WRITE */ #endif /* SIMPLIFIED READ || SIMPLIFIED_WRITE */
#endif /* READ || WRITE */ #endif /* READ || WRITE */