stream_dvd.c includes a pseudo-protocol that recognizes .IFO files, and plays them using libdvdread. This was relatively lazy, and could perhaps easily trigger with files that just had the .ifo extension. Make the checks stricter, and even probe the file header. Apparently the first bytes in an .ifo file are always "DVDVIDEO-VTS", so check for this. Refuse to load the main "video_ts.ifo". The plan is to use stream_dvdnav for it. This also removes at least 1 memory leak.