Harden rangstr_int and rangstr_find against empty Rangstr
Harden rangstr_int and rangstr_find against empty Rangstr

radare/sdb,radare/sdb,radare/sdb,radare/sdb,radare/sdb,radare/sdb,radare/sdb,radare/sdb,radare/sdb,radare/sdb,radare/sdb