lib/wcsrchr-impl.h

   1 /* Search wide string for a wide character.
   2    Copyright (C) 1999, 2011-2020 Free Software Foundation, Inc.
   3    Written by Bruno Haible <bruno@clisp.org>, 1999.
   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 <https://www.gnu.org/licenses/>.  */
  17
  18 wchar_t *
  19 wcsrchr (const wchar_t *wcs, wchar_t wc)
  20 {
  21   /* Calling wcslen and then searching from the other end would cause more
  22      memory accesses.  Avoid that, at the cost of a few more comparisons.  */
  23   wchar_t *result = NULL;
  24
  25   for (;; wcs++)
  26     {
  27       if (*wcs == wc)
  28         result = (wchar_t *) wcs;
  29       if (*wcs == (wchar_t)'\0')
  30         break;
  31     }
  32   return result;
  33 }