Added checks for null pointers
Added checks for null pointers

vlc-mirror/libbluray,vlc-mirror/libbluray,ace20022/libbluray,mwgoldsmith/bluray,pingflood/libbluray,mwgoldsmith/bluray,Azzuro/libbluray,tourettes/libbluray,Azzuro/libbluray,EdwardNewK/libbluray,Azzuro/libbluray,ShiftMediaProject/libbluray,ace20022/libbluray,ShiftMediaProject/libbluray,vlc-mirror/libbluray,koying/libbluray,zxlooong/libbluray,koying/libbluray,Distrotech/libbluray,Distrotech/libbluray,ShiftMediaProject/libbluray,pingflood/libbluray,EdwardNewK/libbluray,pingflood/libbluray,ace20022/libbluray,tourettes/libbluray,UIKit0/libbluray,Azzuro/libbluray,Distrotech/libbluray,EdwardNewK/libbluray,UIKit0/libbluray,zxlooong/libbluray,koying/libbluray,mwgoldsmith/bluray,UIKit0/libbluray,vlc-mirror/libbluray,EdwardNewK/libbluray,zxlooong/libbluray,ShiftMediaProject/libbluray,mwgoldsmith/bluray,Distrotech/libbluray,tourettes/libbluray,koying/libbluray,tourettes/libbluray,UIKit0/libbluray,ace20022/libbluray