1/*
2 * Copyright (c) 1987 Regents of the University of California.
3 * All rights reserved.
4 *
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.
11 */
12
13#ifdef HAVE_CONFIG_H
14#include "config.h"
15#endif
16
17#ifndef lint
18static const char rcsid[] _U_ =
19     "@(#) $Header: /tcpdump/master/tcpdump/strcasecmp.c,v 1.6 2003/11/16 09:36:43 guy Exp $";
20#endif
21
22#include <tcpdump-stdinc.h>
23
24#include "interface.h"
25
26/*
27 * This array is designed for mapping upper and lower case letter
28 * together for a case independent comparison.  The mappings are
29 * based upon ascii character sequences.
30 */
31static u_char charmap[] = {
32	'\000', '\001', '\002', '\003', '\004', '\005', '\006', '\007',
33	'\010', '\011', '\012', '\013', '\014', '\015', '\016', '\017',
34	'\020', '\021', '\022', '\023', '\024', '\025', '\026', '\027',
35	'\030', '\031', '\032', '\033', '\034', '\035', '\036', '\037',
36	'\040', '\041', '\042', '\043', '\044', '\045', '\046', '\047',
37	'\050', '\051', '\052', '\053', '\054', '\055', '\056', '\057',
38	'\060', '\061', '\062', '\063', '\064', '\065', '\066', '\067',
39	'\070', '\071', '\072', '\073', '\074', '\075', '\076', '\077',
40	'\100', '\141', '\142', '\143', '\144', '\145', '\146', '\147',
41	'\150', '\151', '\152', '\153', '\154', '\155', '\156', '\157',
42	'\160', '\161', '\162', '\163', '\164', '\165', '\166', '\167',
43	'\170', '\171', '\172', '\133', '\134', '\135', '\136', '\137',
44	'\140', '\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', '\173', '\174', '\175', '\176', '\177',
48	'\200', '\201', '\202', '\203', '\204', '\205', '\206', '\207',
49	'\210', '\211', '\212', '\213', '\214', '\215', '\216', '\217',
50	'\220', '\221', '\222', '\223', '\224', '\225', '\226', '\227',
51	'\230', '\231', '\232', '\233', '\234', '\235', '\236', '\237',
52	'\240', '\241', '\242', '\243', '\244', '\245', '\246', '\247',
53	'\250', '\251', '\252', '\253', '\254', '\255', '\256', '\257',
54	'\260', '\261', '\262', '\263', '\264', '\265', '\266', '\267',
55	'\270', '\271', '\272', '\273', '\274', '\275', '\276', '\277',
56	'\300', '\341', '\342', '\343', '\344', '\345', '\346', '\347',
57	'\350', '\351', '\352', '\353', '\354', '\355', '\356', '\357',
58	'\360', '\361', '\362', '\363', '\364', '\365', '\366', '\367',
59	'\370', '\371', '\372', '\333', '\334', '\335', '\336', '\337',
60	'\340', '\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', '\373', '\374', '\375', '\376', '\377',
64};
65
66int
67strcasecmp(s1, s2)
68	const char *s1, *s2;
69{
70	register u_char	*cm = charmap,
71			*us1 = (u_char *)s1,
72			*us2 = (u_char *)s2;
73
74	while (cm[*us1] == cm[*us2++])
75		if (*us1++ == '\0')
76			return(0);
77	return(cm[*us1] - cm[*--us2]);
78}
79
80int
81strncasecmp(s1, s2, n)
82	const char *s1, *s2;
83	register int n;
84{
85	register u_char	*cm = charmap,
86			*us1 = (u_char *)s1,
87			*us2 = (u_char *)s2;
88
89	while (--n >= 0 && cm[*us1] == cm[*us2++])
90		if (*us1++ == '\0')
91			return(0);
92	return(n < 0 ? 0 : cm[*us1] - cm[*--us2]);
93}
94