xref: /xnu-10063.101.15/libsyscall/wrappers/string/strcmp.c (revision 94d3b452840153a99b38a3a9659680b2a006908e)
1*94d3b452SApple OSS Distributions /*-
2*94d3b452SApple OSS Distributions  * Copyright (c) 1990, 1993
3*94d3b452SApple OSS Distributions  *	The Regents of the University of California.  All rights reserved.
4*94d3b452SApple OSS Distributions  *
5*94d3b452SApple OSS Distributions  * This code is derived from software contributed to Berkeley by
6*94d3b452SApple OSS Distributions  * Chris Torek.
7*94d3b452SApple OSS Distributions  *
8*94d3b452SApple OSS Distributions  * Redistribution and use in source and binary forms, with or without
9*94d3b452SApple OSS Distributions  * modification, are permitted provided that the following conditions
10*94d3b452SApple OSS Distributions  * are met:
11*94d3b452SApple OSS Distributions  * 1. Redistributions of source code must retain the above copyright
12*94d3b452SApple OSS Distributions  *    notice, this list of conditions and the following disclaimer.
13*94d3b452SApple OSS Distributions  * 2. Redistributions in binary form must reproduce the above copyright
14*94d3b452SApple OSS Distributions  *    notice, this list of conditions and the following disclaimer in the
15*94d3b452SApple OSS Distributions  *    documentation and/or other materials provided with the distribution.
16*94d3b452SApple OSS Distributions  * 4. Neither the name of the University nor the names of its contributors
17*94d3b452SApple OSS Distributions  *    may be used to endorse or promote products derived from this software
18*94d3b452SApple OSS Distributions  *    without specific prior written permission.
19*94d3b452SApple OSS Distributions  *
20*94d3b452SApple OSS Distributions  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21*94d3b452SApple OSS Distributions  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22*94d3b452SApple OSS Distributions  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23*94d3b452SApple OSS Distributions  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24*94d3b452SApple OSS Distributions  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25*94d3b452SApple OSS Distributions  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26*94d3b452SApple OSS Distributions  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27*94d3b452SApple OSS Distributions  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28*94d3b452SApple OSS Distributions  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29*94d3b452SApple OSS Distributions  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30*94d3b452SApple OSS Distributions  * SUCH DAMAGE.
31*94d3b452SApple OSS Distributions  */
32*94d3b452SApple OSS Distributions 
33*94d3b452SApple OSS Distributions #include "string.h"
34*94d3b452SApple OSS Distributions 
35*94d3b452SApple OSS Distributions /*
36*94d3b452SApple OSS Distributions  * Compare strings.
37*94d3b452SApple OSS Distributions  */
38*94d3b452SApple OSS Distributions __attribute__((visibility("hidden")))
39*94d3b452SApple OSS Distributions int
_libkernel_strcmp(const char * s1,const char * s2)40*94d3b452SApple OSS Distributions _libkernel_strcmp(const char *s1, const char *s2)
41*94d3b452SApple OSS Distributions {
42*94d3b452SApple OSS Distributions 	while (*s1 == *s2++) {
43*94d3b452SApple OSS Distributions 		if (*s1++ == '\0') {
44*94d3b452SApple OSS Distributions 			return 0;
45*94d3b452SApple OSS Distributions 		}
46*94d3b452SApple OSS Distributions 	}
47*94d3b452SApple OSS Distributions 	return *(const unsigned char *)s1 - *(const unsigned char *)(s2 - 1);
48*94d3b452SApple OSS Distributions }
49