contrib/tcp_wrappers/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 the above copyright notice and this paragraph are
   7  * duplicated in all such forms and that any documentation,
   8  * advertising materials, and other materials related to such
   9  * distribution and use acknowledge that the software was developed
  10  * by the University of California, Berkeley.  The name of the
  11  * University may not be used to endorse or promote products derived
  12  * from this software without specific prior written permission.
  13  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
  14  * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
  15  * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
  16  */
  17
  18 #if defined(LIBC_SCCS) && !defined(lint)
  19 static char sccsid[] = "@(#)strcasecmp.c        5.6 (Berkeley) 6/27/88";
  20 #endif /* LIBC_SCCS and not lint */
  21
  22 /* Some environments don't define u_char -- WZV */
  23 #if 0
  24 #include <sys/types.h>
  25 #else
  26 typedef unsigned char u_char;
  27 #endif
  28
  29 /*
  30  * This array is designed for mapping upper and lower case letter
  31  * together for a case independent comparison.  The mappings are
  32  * based upon ascii character sequences.
  33  */
  34 static u_char charmap[] = {
  35         '\000', '\001', '\002', '\003', '\004', '\005', '\006', '\007',
  36         '\010', '\011', '\012', '\013', '\014', '\015', '\016', '\017',
  37         '\020', '\021', '\022', '\023', '\024', '\025', '\026', '\027',
  38         '\030', '\031', '\032', '\033', '\034', '\035', '\036', '\037',
  39         '\040', '\041', '\042', '\043', '\044', '\045', '\046', '\047',
  40         '\050', '\051', '\052', '\053', '\054', '\055', '\056', '\057',
  41         '\060', '\061', '\062', '\063', '\064', '\065', '\066', '\067',
  42         '\070', '\071', '\072', '\073', '\074', '\075', '\076', '\077',
  43         '\100', '\141', '\142', '\143', '\144', '\145', '\146', '\147',
  44         '\150', '\151', '\152', '\153', '\154', '\155', '\156', '\157',
  45         '\160', '\161', '\162', '\163', '\164', '\165', '\166', '\167',
  46         '\170', '\171', '\172', '\133', '\134', '\135', '\136', '\137',
  47         '\140', '\141', '\142', '\143', '\144', '\145', '\146', '\147',
  48         '\150', '\151', '\152', '\153', '\154', '\155', '\156', '\157',
  49         '\160', '\161', '\162', '\163', '\164', '\165', '\166', '\167',
  50         '\170', '\171', '\172', '\173', '\174', '\175', '\176', '\177',
  51         '\200', '\201', '\202', '\203', '\204', '\205', '\206', '\207',
  52         '\210', '\211', '\212', '\213', '\214', '\215', '\216', '\217',
  53         '\220', '\221', '\222', '\223', '\224', '\225', '\226', '\227',
  54         '\230', '\231', '\232', '\233', '\234', '\235', '\236', '\237',
  55         '\240', '\241', '\242', '\243', '\244', '\245', '\246', '\247',
  56         '\250', '\251', '\252', '\253', '\254', '\255', '\256', '\257',
  57         '\260', '\261', '\262', '\263', '\264', '\265', '\266', '\267',
  58         '\270', '\271', '\272', '\273', '\274', '\275', '\276', '\277',
  59         '\300', '\341', '\342', '\343', '\344', '\345', '\346', '\347',
  60         '\350', '\351', '\352', '\353', '\354', '\355', '\356', '\357',
  61         '\360', '\361', '\362', '\363', '\364', '\365', '\366', '\367',
  62         '\370', '\371', '\372', '\333', '\334', '\335', '\336', '\337',
  63         '\340', '\341', '\342', '\343', '\344', '\345', '\346', '\347',
  64         '\350', '\351', '\352', '\353', '\354', '\355', '\356', '\357',
  65         '\360', '\361', '\362', '\363', '\364', '\365', '\366', '\367',
  66         '\370', '\371', '\372', '\373', '\374', '\375', '\376', '\377',
  67 };
  68
  69 strcasecmp(s1, s2)
  70         char *s1, *s2;
  71 {
  72         register u_char *cm = charmap,
  73                         *us1 = (u_char *)s1,
  74                         *us2 = (u_char *)s2;
  75
  76         while (cm[*us1] == cm[*us2++])
  77                 if (*us1++ == '\0')
  78                         return(0);
  79         return(cm[*us1] - cm[*--us2]);
  80 }
  81
  82 strncasecmp(s1, s2, n)
  83         char *s1, *s2;
  84         register int n;
  85 {
  86         register u_char *cm = charmap,
  87                         *us1 = (u_char *)s1,
  88                         *us2 = (u_char *)s2;
  89
  90         while (--n >= 0 && cm[*us1] == cm[*us2++])
  91                 if (*us1++ == '\0')
  92                         return(0);
  93         return(n < 0 ? 0 : cm[*us1] - cm[*--us2]);
  94 }