Until now, bound check would simply trace the values and the range. This
enhances the trace by also tracing the name of the variable that was to be set
or read. This is not magically perfect in all cases, but greatly speed the
debugging work. Here's an example before and after this change:
Before: gst_h264_parser_parse_slice_hdr: value not in allowed range. value: 819183, range -87-77
After: gst_h264_parser_parse_slice_hdr: value for 'slice->slice_qp_delta' not in allowed range. value: 819183, range -87-77
Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-bad/-/merge_requests/1356>
Add a separate epb_cache variable to the codecparser NalReader to
detect Emulation Prevention Bytes separately from the main bit cache.
This fixes problems where the existing logic can mistakenly detect
multiple EPB with a sequence like: 0x00 0x00 0x03 0x00 0x03. In that
case, the 5th byte should not be regarded as an EPB.
READ_UE_ALLOWED was almost exclusively used with min == 0, which doesn't
make much point for unsigned integers.
Add a READ_UE_MAX variant and use that instead. Also replaced two usages
of CHECK_ALLOWED (a,0,something) by CHECK_ALLOWED_MAX (a, something)
Add nal_reader_skip_long() helper function to allow an arbitrary number
of bits to be skipped. The former nal_reader_skip() function is too
limited to the actual cache size.
Use this new function to simplify gst_h264_parser_parse_sei_message()
default case, that skips unsupported payloads.
v2: made args consistent from header to source file.
Signed-off-by: Gwenole Beauchesne <gwenole.beauchesne@intel.com>
The payloadSize does not account for emulation prevention bytes. So,
just use nal_reader_skip() for skipping payload_size bits. It should
be possible to further optimize this code since the NAL reader shall
be aligned to byte boundary already.
Kill the now unused nal_reader_skip_to_next_byte() function.
https://bugzilla.gnome.org/show_bug.cgi?id=726829
Signed-off-by: Gwenole Beauchesne <gwenole.beauchesne@intel.com>