lib/sh/strcasecmp.c

   1 /* strcasecmp.c - functions for case-insensitive string comparison. */
   2
   3 /* Copyright (C) 1995 Free Software Foundation, Inc.
   4
   5    This file is part of GNU Bash, the Bourne Again SHell.
   6
   7    Bash is free software; you can redistribute it and/or modify it under
   8    the terms of the GNU General Public License as published by the Free
   9    Software Foundation; either version 2, or (at your option) any later
  10    version.
  11
  12    Bash is distributed in the hope that it will be useful, but WITHOUT ANY
  13    WARRANTY; without even the implied warranty of MERCHANTABILITY or
  14    FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  15    for more details.
  16
  17    You should have received a copy of the GNU General Public License along
  18    with Bash; see the file COPYING.  If not, write to the Free Software
  19    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307, USA */
  20
  21 #include <config.h>
  22
  23 #if !defined (HAVE_STRCASECMP)
  24
  25 #include <stdc.h>
  26 #include <bashansi.h>
  27 #include <ctype.h>
  28
  29 #if !defined (to_lower)
  30 #  define to_lower(c) (islower(c) ? (c) : tolower(c))
  31 #endif /* to_lower */
  32
  33 /* Compare at most COUNT characters from string1 to string2.  Case
  34    doesn't matter. */
  35 int
  36 strncasecmp (string1, string2, count)
  37      const char *string1;
  38      const char *string2;
  39      int count;
  40 {
  41   register const char *s1;
  42   register const char *s2;
  43   register int r;
  44
  45   if (count <= 0 || (string1 == string2))
  46     return 0;
  47
  48   s1 = string1;
  49   s2 = string2;
  50   do
  51     {
  52       if ((r = to_lower (*s1) - to_lower (*s2)) != 0)
  53         return r;
  54       if (*s1++ == '\0')
  55         break;
  56       s2++;
  57     }
  58   while (--count != 0);
  59
  60   return (0);
  61 }
  62
  63 /* strcmp (), but caseless. */
  64 int
  65 strcasecmp (string1, string2)
  66      const char *string1;
  67      const char *string2;
  68 {
  69   register const char *s1;
  70   register const char *s2;
  71   register int r;
  72
  73   s1 = string1;
  74   s2 = string2;
  75
  76   if (s1 == s2)
  77     return (0);
  78
  79   while ((r = to_lower (*s1) - to_lower (*s2)) == 0)
  80     {
  81       if (*s1++ == '\0')
  82         return 0;
  83       s2++;
  84     }
  85
  86   return (r);
  87 }
  88 #endif /* !HAVE_STRCASECMP */