xref: /xnu-8792.81.2/libsyscall/wrappers/string/strcmp.c (revision 19c3b8c28c31cb8130e034cfb5df6bf9ba342d90)
1*19c3b8c2SApple OSS Distributions /*-
2*19c3b8c2SApple OSS Distributions  * Copyright (c) 1990, 1993
3*19c3b8c2SApple OSS Distributions  *	The Regents of the University of California.  All rights reserved.
4*19c3b8c2SApple OSS Distributions  *
5*19c3b8c2SApple OSS Distributions  * This code is derived from software contributed to Berkeley by
6*19c3b8c2SApple OSS Distributions  * Chris Torek.
7*19c3b8c2SApple OSS Distributions  *
8*19c3b8c2SApple OSS Distributions  * Redistribution and use in source and binary forms, with or without
9*19c3b8c2SApple OSS Distributions  * modification, are permitted provided that the following conditions
10*19c3b8c2SApple OSS Distributions  * are met:
11*19c3b8c2SApple OSS Distributions  * 1. Redistributions of source code must retain the above copyright
12*19c3b8c2SApple OSS Distributions  *    notice, this list of conditions and the following disclaimer.
13*19c3b8c2SApple OSS Distributions  * 2. Redistributions in binary form must reproduce the above copyright
14*19c3b8c2SApple OSS Distributions  *    notice, this list of conditions and the following disclaimer in the
15*19c3b8c2SApple OSS Distributions  *    documentation and/or other materials provided with the distribution.
16*19c3b8c2SApple OSS Distributions  * 4. Neither the name of the University nor the names of its contributors
17*19c3b8c2SApple OSS Distributions  *    may be used to endorse or promote products derived from this software
18*19c3b8c2SApple OSS Distributions  *    without specific prior written permission.
19*19c3b8c2SApple OSS Distributions  *
20*19c3b8c2SApple OSS Distributions  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21*19c3b8c2SApple OSS Distributions  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22*19c3b8c2SApple OSS Distributions  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23*19c3b8c2SApple OSS Distributions  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24*19c3b8c2SApple OSS Distributions  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25*19c3b8c2SApple OSS Distributions  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26*19c3b8c2SApple OSS Distributions  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27*19c3b8c2SApple OSS Distributions  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28*19c3b8c2SApple OSS Distributions  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29*19c3b8c2SApple OSS Distributions  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30*19c3b8c2SApple OSS Distributions  * SUCH DAMAGE.
31*19c3b8c2SApple OSS Distributions  */
32*19c3b8c2SApple OSS Distributions 
33*19c3b8c2SApple OSS Distributions #include "string.h"
34*19c3b8c2SApple OSS Distributions 
35*19c3b8c2SApple OSS Distributions /*
36*19c3b8c2SApple OSS Distributions  * Compare strings.
37*19c3b8c2SApple OSS Distributions  */
38*19c3b8c2SApple OSS Distributions __attribute__((visibility("hidden")))
39*19c3b8c2SApple OSS Distributions int
_libkernel_strcmp(const char * s1,const char * s2)40*19c3b8c2SApple OSS Distributions _libkernel_strcmp(const char *s1, const char *s2)
41*19c3b8c2SApple OSS Distributions {
42*19c3b8c2SApple OSS Distributions 	while (*s1 == *s2++) {
43*19c3b8c2SApple OSS Distributions 		if (*s1++ == '\0') {
44*19c3b8c2SApple OSS Distributions 			return 0;
45*19c3b8c2SApple OSS Distributions 		}
46*19c3b8c2SApple OSS Distributions 	}
47*19c3b8c2SApple OSS Distributions 	return *(const unsigned char *)s1 - *(const unsigned char *)(s2 - 1);
48*19c3b8c2SApple OSS Distributions }
49