xref: /xnu-8796.121.2/libsyscall/wrappers/string/strcmp.c (revision c54f35ca767986246321eb901baf8f5ff7923f6a)
1*c54f35caSApple OSS Distributions /*-
2*c54f35caSApple OSS Distributions  * Copyright (c) 1990, 1993
3*c54f35caSApple OSS Distributions  *	The Regents of the University of California.  All rights reserved.
4*c54f35caSApple OSS Distributions  *
5*c54f35caSApple OSS Distributions  * This code is derived from software contributed to Berkeley by
6*c54f35caSApple OSS Distributions  * Chris Torek.
7*c54f35caSApple OSS Distributions  *
8*c54f35caSApple OSS Distributions  * Redistribution and use in source and binary forms, with or without
9*c54f35caSApple OSS Distributions  * modification, are permitted provided that the following conditions
10*c54f35caSApple OSS Distributions  * are met:
11*c54f35caSApple OSS Distributions  * 1. Redistributions of source code must retain the above copyright
12*c54f35caSApple OSS Distributions  *    notice, this list of conditions and the following disclaimer.
13*c54f35caSApple OSS Distributions  * 2. Redistributions in binary form must reproduce the above copyright
14*c54f35caSApple OSS Distributions  *    notice, this list of conditions and the following disclaimer in the
15*c54f35caSApple OSS Distributions  *    documentation and/or other materials provided with the distribution.
16*c54f35caSApple OSS Distributions  * 4. Neither the name of the University nor the names of its contributors
17*c54f35caSApple OSS Distributions  *    may be used to endorse or promote products derived from this software
18*c54f35caSApple OSS Distributions  *    without specific prior written permission.
19*c54f35caSApple OSS Distributions  *
20*c54f35caSApple OSS Distributions  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21*c54f35caSApple OSS Distributions  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22*c54f35caSApple OSS Distributions  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23*c54f35caSApple OSS Distributions  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24*c54f35caSApple OSS Distributions  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25*c54f35caSApple OSS Distributions  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26*c54f35caSApple OSS Distributions  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27*c54f35caSApple OSS Distributions  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28*c54f35caSApple OSS Distributions  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29*c54f35caSApple OSS Distributions  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30*c54f35caSApple OSS Distributions  * SUCH DAMAGE.
31*c54f35caSApple OSS Distributions  */
32*c54f35caSApple OSS Distributions 
33*c54f35caSApple OSS Distributions #include "string.h"
34*c54f35caSApple OSS Distributions 
35*c54f35caSApple OSS Distributions /*
36*c54f35caSApple OSS Distributions  * Compare strings.
37*c54f35caSApple OSS Distributions  */
38*c54f35caSApple OSS Distributions __attribute__((visibility("hidden")))
39*c54f35caSApple OSS Distributions int
_libkernel_strcmp(const char * s1,const char * s2)40*c54f35caSApple OSS Distributions _libkernel_strcmp(const char *s1, const char *s2)
41*c54f35caSApple OSS Distributions {
42*c54f35caSApple OSS Distributions 	while (*s1 == *s2++) {
43*c54f35caSApple OSS Distributions 		if (*s1++ == '\0') {
44*c54f35caSApple OSS Distributions 			return 0;
45*c54f35caSApple OSS Distributions 		}
46*c54f35caSApple OSS Distributions 	}
47*c54f35caSApple OSS Distributions 	return *(const unsigned char *)s1 - *(const unsigned char *)(s2 - 1);
48*c54f35caSApple OSS Distributions }
49