wcsmbs/wcstok.c

   1 /* Copyright (C) 1995-2018 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 (wchar_t *wcs, const wchar_t *delim, wchar_t **save_ptr)
  27 {
  28   wchar_t *result;
  29
  30   if (wcs == NULL)
  31     {
  32       if (*save_ptr == NULL)
  33         {
  34           __set_errno (EINVAL);
  35           return NULL;
  36         }
  37       else
  38         wcs = *save_ptr;
  39     }
  40
  41   /* Scan leading delimiters.  */
  42   wcs += wcsspn (wcs, delim);
  43   if (*wcs == L'\0')
  44     {
  45       *save_ptr = NULL;
  46       return NULL;
  47     }
  48
  49   /* Find the end of the token.  */
  50   result = wcs;
  51   wcs = wcspbrk (result, delim);
  52   if (wcs == NULL)
  53     /* This token finishes the string.  */
  54     *save_ptr = NULL;
  55   else
  56     {
  57       /* Terminate the token and make *SAVE_PTR point past it.  */
  58       *wcs = L'\0';
  59       *save_ptr = wcs + 1;
  60     }
  61   return result;
  62 }