ref: fb7dd4b3a868cb8987049c95bb32e6425a73c8b9 dir: purgatorio/libkern/toupper.c
toupper(int c) { if(c < 'a' || c > 'z') return c; return (c-'a'+'A'); } tolower(int c) { if(c < 'A' || c > 'Z') return c; return (c-'A'+'a'); }