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      1 /* Searching a string for the last occurrence of a character.
      2    Copyright (C) 2007-2012 Free Software Foundation, Inc.
      3    Written by Bruno Haible <bruno (at) clisp.org>, 2007.
      4 
      5    This program is free software: you can redistribute it and/or modify
      6    it under the terms of the GNU General Public License as published by
      7    the Free Software Foundation; either version 3 of the License, or
      8    (at your option) any later version.
      9 
     10    This program is distributed in the hope that it will be useful,
     11    but WITHOUT ANY WARRANTY; without even the implied warranty of
     12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
     13    GNU General Public License for more details.
     14 
     15    You should have received a copy of the GNU General Public License
     16    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
     17 
     18 #include <config.h>
     19 
     20 /* Specification.  */
     21 #include <string.h>
     22 
     23 #include "mbuiter.h"
     24 
     25 /* Locate the last single-byte character C in the character string STRING,
     26    and return a pointer to it.  Return NULL if C is not found in STRING.  */
     27 char *
     28 mbsrchr (const char *string, int c)
     29 {
     30   if (MB_CUR_MAX > 1
     31       /* Optimization: We know that ASCII characters < 0x30 don't occur as
     32          part of multibyte characters longer than 1 byte.  Hence, if c < 0x30,
     33          the faster unibyte loop can be used.  */
     34       && (unsigned char) c >= 0x30)
     35     {
     36       const char *result = NULL;
     37       mbui_iterator_t iter;
     38 
     39       for (mbui_init (iter, string); mbui_avail (iter); mbui_advance (iter))
     40         {
     41           if (mb_len (mbui_cur (iter)) == 1
     42               && (unsigned char) * mbui_cur_ptr (iter) == (unsigned char) c)
     43             result = mbui_cur_ptr (iter);
     44         }
     45       return (char *) result;
     46     }
     47   else
     48     return strrchr (string, c);
     49 }
     50