lib/sh/mbscmp.c

   1 /* mbscmp - multibyte string comparison. */
   2
   3 /* Copyright (C) 1995-2015 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
   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    Bash 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 Bash.  If not, see <http://www.gnu.org/licenses/>.
  19 */
  20
  21 #include <config.h>
  22
  23 #if !defined (HAVE_MBSCMP) && defined (HANDLE_MULTIBYTE)
  24
  25 #include <stdlib.h>
  26 #include <stddef.h>
  27 #include <string.h>
  28
  29 /* Compare MBS1 and MBS2.  */
  30 int
  31 mbscmp (mbs1, mbs2)
  32     const char *mbs1;
  33     const char *mbs2;
  34 {
  35   int len1, len2, mb_cur_max;
  36   wchar_t c1, c2;
  37
  38   len1 = len2 = 0;
  39   /* Reset multibyte characters to their initial state.  */
  40   (void) mblen ((char *) NULL, 0);
  41
  42   mb_cur_max = MB_CUR_MAX;
  43   do
  44     {
  45       len1 = mbtowc (&c1, mbs1, mb_cur_max);
  46       len2 = mbtowc (&c2, mbs2, mb_cur_max);
  47
  48       if (len1 == 0)
  49         return len2 == 0 ? 0 : -1;
  50       else if (len2 == 0)
  51         return 1;
  52       else if (len1 > 0 && len2 < 0)
  53         return -1;
  54       else if (len1 < 0 && len2 > 0)
  55         return 1;
  56       else if (len1 < 0 && len2 < 0)
  57         {
  58           len1 = strlen (mbs1);
  59           len2 = strlen (mbs2);
  60           return (len1 == len2 ? memcmp (mbs1, mbs2, len1)
  61                                : ((len1 < len2) ? (memcmp (mbs1, mbs2, len1) > 0 ? 1 : -1)
  62                                                 : (memcmp (mbs1, mbs2, len2) >= 0 ? 1 : -1)));
  63         }
  64
  65       mbs1 += len1;
  66       mbs2 += len2;
  67     }
  68   while (c1 == c2);
  69
  70   return c1 - c2;
  71 }
  72
  73 #endif