lib/sh/mbscasecmp.c

   1 /* mbscasecmp - case-insensitive multibyte string comparison. */
   2
   3 /* Copyright (C) 2009-2015 Free Software Foundation, Inc.
   4
   5    This file is part of GNU Bush, the Bourne Again SHell.
   6
   7    Bush is free software: you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation, either version 3 of the License, or
  10    (at your option) any later version.
  11
  12    Bush is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with Bush.  If not, see <http://www.gnu.org/licenses/>.
  19 */
  20
  21 #include <config.h>
  22
  23 #if !defined (HAVE_MBSCASECMP) && defined (HANDLE_MULTIBYTE)
  24
  25 #include <stdlib.h>
  26 #include <stddef.h>
  27 #include <string.h>
  28
  29 #include <wchar.h>
  30 #include <wctype.h>
  31
  32 /* Compare MBS1 and MBS2 without regard to case.  */
  33 int
  34 mbscasecmp (mbs1, mbs2)
  35     const char *mbs1;
  36     const char *mbs2;
  37 {
  38   int len1, len2, mb_cur_max;
  39   wchar_t c1, c2, l1, l2;
  40
  41   len1 = len2 = 0;
  42   /* Reset multibyte characters to their initial state.  */
  43   (void) mblen ((char *) NULL, 0);
  44
  45   mb_cur_max = MB_CUR_MAX;
  46   do
  47     {
  48       len1 = mbtowc (&c1, mbs1, mb_cur_max);
  49       len2 = mbtowc (&c2, mbs2, mb_cur_max);
  50
  51       if (len1 == 0)
  52         return len2 == 0 ? 0 : -1;
  53       else if (len2 == 0)
  54         return 1;
  55       else if (len1 > 0 && len2 < 0)
  56         return -1;
  57       else if (len1 < 0 && len2 > 0)
  58         return 1;
  59       else if (len1 < 0 && len2 < 0)
  60         {
  61           len1 = strlen (mbs1);
  62           len2 = strlen (mbs2);
  63           return (len1 == len2 ? memcmp (mbs1, mbs2, len1)
  64                                : ((len1 < len2) ? (memcmp (mbs1, mbs2, len1) > 0 ? 1 : -1)
  65                                                 : (memcmp (mbs1, mbs2, len2) >= 0 ? 1 : -1)));
  66         }
  67
  68       l1 = towlower (c1);
  69       l2 = towlower (c2);
  70
  71       mbs1 += len1;
  72       mbs2 += len2;
  73     }
  74   while (l1 == l2);
  75
  76   return l1 - l2;
  77 }
  78
  79 #endif