1 /*
2 * Copyright (c) 1987, 1993
3 * The Regents of the University of California. All rights reserved.
4 *
5 * %sccs.include.redist.c%
6 */
7
8 #include <sys/cdefs.h>
9 #include <string.h>
10
11 #if defined(LIBC_SCCS) && !defined(lint)
12 static char sccsid[] = "@(#)strcasecmp.c 8.1 (Berkeley) 06/04/93";
13 #endif /* LIBC_SCCS and not lint */
14
15 typedef unsigned char u_char;
16
17 /*
18 * This array is designed for mapping upper and lower case letter
19 * together for a case independent comparison. The mappings are
20 * based upon ascii character sequences.
21 */
22 static const u_char charmap[] = {
23 '\000', '\001', '\002', '\003', '\004', '\005', '\006', '\007',
24 '\010', '\011', '\012', '\013', '\014', '\015', '\016', '\017',
25 '\020', '\021', '\022', '\023', '\024', '\025', '\026', '\027',
26 '\030', '\031', '\032', '\033', '\034', '\035', '\036', '\037',
27 '\040', '\041', '\042', '\043', '\044', '\045', '\046', '\047',
28 '\050', '\051', '\052', '\053', '\054', '\055', '\056', '\057',
29 '\060', '\061', '\062', '\063', '\064', '\065', '\066', '\067',
30 '\070', '\071', '\072', '\073', '\074', '\075', '\076', '\077',
31 '\100', '\141', '\142', '\143', '\144', '\145', '\146', '\147',
32 '\150', '\151', '\152', '\153', '\154', '\155', '\156', '\157',
33 '\160', '\161', '\162', '\163', '\164', '\165', '\166', '\167',
34 '\170', '\171', '\172', '\133', '\134', '\135', '\136', '\137',
35 '\140', '\141', '\142', '\143', '\144', '\145', '\146', '\147',
36 '\150', '\151', '\152', '\153', '\154', '\155', '\156', '\157',
37 '\160', '\161', '\162', '\163', '\164', '\165', '\166', '\167',
38 '\170', '\171', '\172', '\173', '\174', '\175', '\176', '\177',
39 '\200', '\201', '\202', '\203', '\204', '\205', '\206', '\207',
40 '\210', '\211', '\212', '\213', '\214', '\215', '\216', '\217',
41 '\220', '\221', '\222', '\223', '\224', '\225', '\226', '\227',
42 '\230', '\231', '\232', '\233', '\234', '\235', '\236', '\237',
43 '\240', '\241', '\242', '\243', '\244', '\245', '\246', '\247',
44 '\250', '\251', '\252', '\253', '\254', '\255', '\256', '\257',
45 '\260', '\261', '\262', '\263', '\264', '\265', '\266', '\267',
46 '\270', '\271', '\272', '\273', '\274', '\275', '\276', '\277',
47 '\300', '\301', '\302', '\303', '\304', '\305', '\306', '\307',
48 '\310', '\311', '\312', '\313', '\314', '\315', '\316', '\317',
49 '\320', '\321', '\322', '\323', '\324', '\325', '\326', '\327',
50 '\330', '\331', '\332', '\333', '\334', '\335', '\336', '\337',
51 '\340', '\341', '\342', '\343', '\344', '\345', '\346', '\347',
52 '\350', '\351', '\352', '\353', '\354', '\355', '\356', '\357',
53 '\360', '\361', '\362', '\363', '\364', '\365', '\366', '\367',
54 '\370', '\371', '\372', '\373', '\374', '\375', '\376', '\377',
55 };
56
57 int
strcasecmp(s1,s2)58 strcasecmp(s1, s2)
59 const char *s1, *s2;
60 {
61 register const u_char *cm = charmap,
62 *us1 = (const u_char *)s1,
63 *us2 = (const u_char *)s2;
64
65 while (cm[*us1] == cm[*us2++])
66 if (*us1++ == '\0')
67 return (0);
68 return (cm[*us1] - cm[*--us2]);
69 }
70
71 int
strncasecmp(s1,s2,n)72 strncasecmp(s1, s2, n)
73 const char *s1, *s2;
74 register size_t n;
75 {
76 if (n != 0) {
77 register const u_char *cm = charmap,
78 *us1 = (const u_char *)s1,
79 *us2 = (const u_char *)s2;
80
81 do {
82 if (cm[*us1] != cm[*us2++])
83 return (cm[*us1] - cm[*--us2]);
84 if (*us1++ == '\0')
85 break;
86 } while (--n != 0);
87 }
88 return (0);
89 }
90