kc3-lang/libjpeg-turbo

2016-05-10T21:04:02

Don't allow opaque source/dest mgrs to be swapped Calling jpeg_stdio_dest() followed by jpeg_mem_dest(), or jpeg_mem_src() followed by jpeg_stdio_src(), is dangerous, because the existing opaque structure would not be big enough to accommodate the new source/dest manager. This issue was non-obvious to libjpeg-turbo consumers, since it was only documented in code comments. Furthermore, the issue could also occur if the source/dest manager was allocated by the calling program, but it was not allocated with enough space to accommodate the opaque stdio or memory source/dest manager structs. The safest thing to do is to throw an error if one of these functions is called when there is already a source/dest manager assigned to the object and it was allocated elsewhere. Closes #78, #79