wcsmbs/mbsrchr.c

   1 /* Copyright (C) 1995 Free Software Foundation, Inc.
   2 This file is part of the GNU C Library.
   3
   4 The GNU C Library is free software; you can redistribute it and/or
   5 modify it under the terms of the GNU Library General Public License as
   6 published by the Free Software Foundation; either version 2 of the
   7 License, or (at your option) any later version.
   8
   9 The GNU C Library is distributed in the hope that it will be useful,
  10 but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12 Library General Public License for more details.
  13
  14 You should have received a copy of the GNU Library General Public
  15 License along with the GNU C Library; see the file COPYING.LIB.  If
  16 not, write to the Free Software Foundation, Inc., 675 Mass Ave,
  17 Cambridge, MA 02139, USA.  */
  18
  19 #include <mbstr.h>
  20 #include <stdlib.h>
  21
  22 #define __need_wchar_t
  23 #include <stddef.h>
  24
  25
  26 /* Find the last occurence of MBC in MBS.  */
  27 char *
  28 mbsrchr (mbs, mbc)
  29     const char *mbs;
  30     mbchar_t mbc;
  31 {
  32   const char * retval = NULL;
  33   int clen;
  34   wchar_t wc;
  35   wchar_t c;
  36
  37   /* Reset multibyte characters to their initial state.  */
  38   (void) mblen ((char *) NULL, 0);
  39
  40   clen = mbtowc (&wc, (char *) &mbc, MB_CUR_MAX);
  41   if (clen < 0)
  42     /* FIXME: search character MBC is illegal.  */
  43     return NULL;
  44   else if (clen == 0)
  45     wc = L'\0';
  46
  47   clen = 0;
  48   do
  49     {
  50       mbs += clen;
  51       clen = mbtowc (&c, mbs, MB_CUR_MAX);
  52     }
  53   while (clen > 0 && c != wc);
  54
  55   if (clen < 0)
  56     /* FIXME: clen < 0 means illegal character in string.  */
  57     return NULL;
  58
  59   return (char *) (clen > 0 || (clen == 0 && wc == L'\0') ? mbs : retval);
  60 }
  61