RTSP stream hangs on camera going offline

[magistrser]

Also when camera returns stream still hangs. I debugged it a little and find out that for

avcodec_decode_video2(this->video_dec_ctx, this->frame, &got_frame, &(this->packet));

got_frame still be 1 even if avcodec_decode_video2 returns 0. It leads to infinity loop in grab function.
I hope this fix is good enough, or may be you know the right way to fix it