2
* Copyright (c) 1987 Regents of the University of California.
5
* Redistribution and use in source and binary forms are permitted
6
* provided that this notice is preserved and that due credit is given
7
* to the University of California at Berkeley. The name of the University
8
* may not be used to endorse or promote products derived from this
9
* software without specific written prior permission. This software
10
* is provided ``as is'' without express or implied warranty.
15
@deftypefn Supplemental int strncasecmp (const char *@var{s1}, const char *@var{s2})
17
A case-insensitive @code{strncmp}.
23
#if defined(LIBC_SCCS) && !defined(lint)
24
static char sccsid[] = "@(#)strcasecmp.c 5.5 (Berkeley) 11/24/87";
25
#endif /* LIBC_SCCS and not lint */
31
* This array is designed for mapping upper and lower case letter
32
* together for a case independent comparison. The mappings are
33
* based upon ascii character sequences.
35
static const unsigned char charmap[] = {
36
'\000', '\001', '\002', '\003', '\004', '\005', '\006', '\007',
37
'\010', '\011', '\012', '\013', '\014', '\015', '\016', '\017',
38
'\020', '\021', '\022', '\023', '\024', '\025', '\026', '\027',
39
'\030', '\031', '\032', '\033', '\034', '\035', '\036', '\037',
40
'\040', '\041', '\042', '\043', '\044', '\045', '\046', '\047',
41
'\050', '\051', '\052', '\053', '\054', '\055', '\056', '\057',
42
'\060', '\061', '\062', '\063', '\064', '\065', '\066', '\067',
43
'\070', '\071', '\072', '\073', '\074', '\075', '\076', '\077',
44
'\100', '\141', '\142', '\143', '\144', '\145', '\146', '\147',
45
'\150', '\151', '\152', '\153', '\154', '\155', '\156', '\157',
46
'\160', '\161', '\162', '\163', '\164', '\165', '\166', '\167',
47
'\170', '\171', '\172', '\133', '\134', '\135', '\136', '\137',
48
'\140', '\141', '\142', '\143', '\144', '\145', '\146', '\147',
49
'\150', '\151', '\152', '\153', '\154', '\155', '\156', '\157',
50
'\160', '\161', '\162', '\163', '\164', '\165', '\166', '\167',
51
'\170', '\171', '\172', '\173', '\174', '\175', '\176', '\177',
52
'\200', '\201', '\202', '\203', '\204', '\205', '\206', '\207',
53
'\210', '\211', '\212', '\213', '\214', '\215', '\216', '\217',
54
'\220', '\221', '\222', '\223', '\224', '\225', '\226', '\227',
55
'\230', '\231', '\232', '\233', '\234', '\235', '\236', '\237',
56
'\240', '\241', '\242', '\243', '\244', '\245', '\246', '\247',
57
'\250', '\251', '\252', '\253', '\254', '\255', '\256', '\257',
58
'\260', '\261', '\262', '\263', '\264', '\265', '\266', '\267',
59
'\270', '\271', '\272', '\273', '\274', '\275', '\276', '\277',
60
'\300', '\341', '\342', '\343', '\344', '\345', '\346', '\347',
61
'\350', '\351', '\352', '\353', '\354', '\355', '\356', '\357',
62
'\360', '\361', '\362', '\363', '\364', '\365', '\366', '\367',
63
'\370', '\371', '\372', '\333', '\334', '\335', '\336', '\337',
64
'\340', '\341', '\342', '\343', '\344', '\345', '\346', '\347',
65
'\350', '\351', '\352', '\353', '\354', '\355', '\356', '\357',
66
'\360', '\361', '\362', '\363', '\364', '\365', '\366', '\367',
67
'\370', '\371', '\372', '\373', '\374', '\375', '\376', '\377',
71
strncasecmp(const char *s1, const char *s2, register size_t n)
73
register unsigned char u1, u2;
76
u1 = (unsigned char) *s1++;
77
u2 = (unsigned char) *s2++;
78
if (charmap[u1] != charmap[u2]) {
79
return charmap[u1] - charmap[u2];