1 #define _DEFAULT_SOURCE 2 #include <string.h> 3 #include <stdint.h> 4 #include <limits.h> 5 6 #define ALIGN (sizeof(size_t)) 7 #define ONES ((size_t)-1/UCHAR_MAX) 8 #define HIGHS (ONES * (UCHAR_MAX/2+1)) 9 #define HASZERO(x) ((x)-ONES & ~(x) & HIGHS) 10 11 char *strchrnul(const char *s, int c) 12 { 13 c = (unsigned char)c; 14 if (!c) return (char *)s + strlen(s); 15 16 #if 0 17 typedef size_t __attribute__((__may_alias__)) word; 18 const word *w; 19 for (; (uintptr_t)s % ALIGN; s++) 20 if (!*s || *(unsigned char *)s == c) return (char *)s; 21 size_t k = ONES * c; 22 for (w = (void *)s; !HASZERO(*w) && !HASZERO(*w^k); w++); 23 s = (void *)w; 24 #endif 25 for (; *s && *(unsigned char *)s != c; s++); 26 return (char *)s; 27 } 28