contrib/tcpdump-3.9/strcasecmp.c

   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
  18 static 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  */
  31 static 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
  66 int
  67 strcasecmp(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
  80 int
  81 strncasecmp(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 }