1#define _BSD_SOURCE 2#include <string.h> 3#include <stdint.h> 4#include <limits.h> 5#include "libc.h" 6 7#define ALIGN (sizeof(size_t)-1) 8#define ONES ((size_t)-1/UCHAR_MAX) 9#define HIGHS (ONES * (UCHAR_MAX/2+1)) 10#define HASZERO(x) ((x)-ONES & ~(x) & HIGHS) 11 12size_t strlcpy(char *d, const char *s, size_t n) 13{ 14 char *d0 = d; 15 size_t *wd; 16 const size_t *ws; 17 18 if (!n--) goto finish; 19 if (((uintptr_t)s & ALIGN) == ((uintptr_t)d & ALIGN)) { 20 for (; ((uintptr_t)s & ALIGN) && n && (*d=*s); n--, s++, d++); 21 if (n && *s) { 22 wd=(void *)d; ws=(const void *)s; 23 for (; n>=sizeof(size_t) && !HASZERO(*ws); 24 n-=sizeof(size_t), ws++, wd++) *wd = *ws; 25 d=(void *)wd; s=(const void *)ws; 26 } 27 } 28 for (; n && (*d=*s); n--, s++, d++); 29 *d = 0; 30finish: 31 return d-d0 + strlen(s); 32} 33