Movatterモバイル変換

#define _BSD_SOURCE#include <string.h>#include <stdint.h>#include <limits.h>#define ALIGN (sizeof(size_t)-1)#define ONES ((size_t)-1/UCHAR_MAX)#define HIGHS (ONES * (UCHAR_MAX/2+1))#define HASZERO(x) ((x)-ONES & ~(x) & HIGHS)size_t strlcpy(char *d, const char *s, size_t n){char *d0 = d;size_t *wd;if (!n--) goto finish;#ifdef __GNUC__typedef size_t __attribute__((__may_alias__)) word;const word *ws;if (((uintptr_t)s & ALIGN) == ((uintptr_t)d & ALIGN)) {for (; ((uintptr_t)s & ALIGN) && n && (*d=*s); n--, s++, d++);if (n && *s) {wd=(void *)d; ws=(const void *)s;for (; n>=sizeof(size_t) && !HASZERO(*ws);       n-=sizeof(size_t), ws++, wd++) *wd = *ws;d=(void *)wd; s=(const void *)ws;}}#endiffor (; n && (*d=*s); n--, s++, d++);*d = 0;finish:return d-d0 + strlen(s);}