1 /* $OpenBSD: strcasecmp.c,v 1.6 2005/08/08 08:05:37 espie Exp $ */
2
3 /*
4 * Copyright (c) 1987, 1993
5 * The Regents of the University of California. All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 * 3. Neither the name of the University nor the names of its contributors
16 * may be used to endorse or promote products derived from this software
17 * without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 */
31
32 #include <string.h>
33
34 typedef unsigned char u_char;
35
36 /*
37 * This array is designed for mapping upper and lower case letter
38 * together for a case independent comparison. The mappings are
39 * based upon ascii character sequences.
40 */
41 static const u_char charmap[] = {
42 '\000', '\001', '\002', '\003', '\004', '\005', '\006', '\007',
43 '\010', '\011', '\012', '\013', '\014', '\015', '\016', '\017',
44 '\020', '\021', '\022', '\023', '\024', '\025', '\026', '\027',
45 '\030', '\031', '\032', '\033', '\034', '\035', '\036', '\037',
46 '\040', '\041', '\042', '\043', '\044', '\045', '\046', '\047',
47 '\050', '\051', '\052', '\053', '\054', '\055', '\056', '\057',
48 '\060', '\061', '\062', '\063', '\064', '\065', '\066', '\067',
49 '\070', '\071', '\072', '\073', '\074', '\075', '\076', '\077',
50 '\100', '\141', '\142', '\143', '\144', '\145', '\146', '\147',
51 '\150', '\151', '\152', '\153', '\154', '\155', '\156', '\157',
52 '\160', '\161', '\162', '\163', '\164', '\165', '\166', '\167',
53 '\170', '\171', '\172', '\133', '\134', '\135', '\136', '\137',
54 '\140', '\141', '\142', '\143', '\144', '\145', '\146', '\147',
55 '\150', '\151', '\152', '\153', '\154', '\155', '\156', '\157',
56 '\160', '\161', '\162', '\163', '\164', '\165', '\166', '\167',
57 '\170', '\171', '\172', '\173', '\174', '\175', '\176', '\177',
58 '\200', '\201', '\202', '\203', '\204', '\205', '\206', '\207',
59 '\210', '\211', '\212', '\213', '\214', '\215', '\216', '\217',
60 '\220', '\221', '\222', '\223', '\224', '\225', '\226', '\227',
61 '\230', '\231', '\232', '\233', '\234', '\235', '\236', '\237',
62 '\240', '\241', '\242', '\243', '\244', '\245', '\246', '\247',
63 '\250', '\251', '\252', '\253', '\254', '\255', '\256', '\257',
64 '\260', '\261', '\262', '\263', '\264', '\265', '\266', '\267',
65 '\270', '\271', '\272', '\273', '\274', '\275', '\276', '\277',
66 '\300', '\301', '\302', '\303', '\304', '\305', '\306', '\307',
67 '\310', '\311', '\312', '\313', '\314', '\315', '\316', '\317',
68 '\320', '\321', '\322', '\323', '\324', '\325', '\326', '\327',
69 '\330', '\331', '\332', '\333', '\334', '\335', '\336', '\337',
70 '\340', '\341', '\342', '\343', '\344', '\345', '\346', '\347',
71 '\350', '\351', '\352', '\353', '\354', '\355', '\356', '\357',
72 '\360', '\361', '\362', '\363', '\364', '\365', '\366', '\367',
73 '\370', '\371', '\372', '\373', '\374', '\375', '\376', '\377',
74 };
75
76 int
strcasecmp(const char * s1,const char * s2)77 strcasecmp(const char *s1, const char *s2)
78 {
79 const u_char *cm = charmap;
80 const u_char *us1 = (const u_char *)s1;
81 const u_char *us2 = (const u_char *)s2;
82
83 while (cm[*us1] == cm[*us2++])
84 if (*us1++ == '\0')
85 return (0);
86 return (cm[*us1] - cm[*--us2]);
87 }
88
89 int
strncasecmp(const char * s1,const char * s2,size_t n)90 strncasecmp(const char *s1, const char *s2, size_t n)
91 {
92 if (n != 0) {
93 const u_char *cm = charmap;
94 const u_char *us1 = (const u_char *)s1;
95 const u_char *us2 = (const u_char *)s2;
96
97 do {
98 if (cm[*us1] != cm[*us2++])
99 return (cm[*us1] - cm[*--us2]);
100 if (*us1++ == '\0')
101 break;
102 } while (--n != 0);
103 }
104 return (0);
105 }
106