1 /*- 2 * SPDX-License-Identifier: MIT 3 * 4 * Copyright (c) 2005-2014 Rich Felker, et al. 5 * 6 * Permission is hereby granted, free of charge, to any person obtaining 7 * a copy of this software and associated documentation files (the 8 * "Software"), to deal in the Software without restriction, including 9 * without limitation the rights to use, copy, modify, merge, publish, 10 * distribute, sublicense, and/or sell copies of the Software, and to 11 * permit persons to whom the Software is furnished to do so, subject to 12 * the following conditions: 13 * 14 * The above copyright notice and this permission notice shall be 15 * included in all copies or substantial portions of the Software. 16 * 17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 18 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 19 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. 20 * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY 21 * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, 22 * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE 23 * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. 24 */ 25 #include <limits.h> 26 #include <stdint.h> 27 #include <string.h> 28 29 #define ALIGN (sizeof(size_t)) 30 #define ONES ((size_t)-1 / UCHAR_MAX) 31 #define HIGHS (ONES * (UCHAR_MAX / 2 + 1)) 32 #define HASZERO(x) (((x)-ONES) & ~(x)&HIGHS) 33 34 char *__strchrnul(const char *, int); 35 36 char * 37 __strchrnul(const char *s, int c) 38 { 39 c = (unsigned char)c; 40 if (!c) 41 return (char *)s + strlen(s); 42 43 #ifdef __GNUC__ 44 typedef size_t __attribute__((__may_alias__)) word; 45 const word *w; 46 for (; (uintptr_t)s % ALIGN; s++) 47 if (!*s || *(unsigned char *)s == c) 48 return (char *)s; 49 size_t k = ONES * c; 50 for (w = (void *)s; !HASZERO(*w) && !HASZERO(*w ^ k); w++) 51 ; 52 s = (void *)w; 53 #endif 54 for (; *s && *(unsigned char *)s != c; s++) 55 ; 56 return (char *)s; 57 } 58 59 __weak_reference(__strchrnul, strchrnul); 60