wcsmbs/wcstok.c

   1 /* Copyright (C) 1995, 1996, 1997 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3    Contributed by Ulrich Drepper <drepper@gnu.ai.mit.edu>, 1995.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library 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 GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, see
  17    <http://www.gnu.org/licenses/>.  */
  18
  19 #include <wchar.h>
  20 #include <errno.h>
  21
  22
  23 /* Parse WCS into tokens separated by characters in DELIM.  If WCS is
  24    NULL, the last string wcstok() was called with is used.  */
  25 wchar_t *
  26 wcstok (wcs, delim, save_ptr)
  27      wchar_t *wcs;
  28      const wchar_t *delim;
  29      wchar_t **save_ptr;
  30 {
  31   wchar_t *result;
  32
  33   if (wcs == NULL)
  34     {
  35       if (*save_ptr == NULL)
  36         {
  37           __set_errno (EINVAL);
  38           return NULL;
  39         }
  40       else
  41         wcs = *save_ptr;
  42     }
  43
  44   /* Scan leading delimiters.  */
  45   wcs += wcsspn (wcs, delim);
  46   if (*wcs == L'\0')
  47     {
  48       *save_ptr = NULL;
  49       return NULL;
  50     }
  51
  52   /* Find the end of the token.  */
  53   result = wcs;
  54   wcs = wcspbrk (result, delim);
  55   if (wcs == NULL)
  56     /* This token finishes the string.  */
  57     *save_ptr = NULL;
  58   else
  59     {
  60       /* Terminate the token and make *SAVE_PTR point past it.  */
  61       *wcs = L'\0';
  62       *save_ptr = wcs + 1;
  63     }
  64   return result;
  65 }