wcsmbs/wcschr.c

   1 /* Copyright (C) 1995-2019 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 Lesser General Public
   6    License as published by the Free Software Foundation; either
   7    version 2.1 of the 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    Lesser General Public License for more details.
  13
  14    You should have received a copy of the GNU Lesser General Public
  15    License along with the GNU C Library; if not, see
  16    <https://www.gnu.org/licenses/>.  */
  17
  18 #include <wchar.h>
  19 #include <loop_unroll.h>
  20
  21 #ifndef WCSCHR
  22 # define WCSCHR __wcschr
  23 #endif
  24
  25 /* Find the first occurrence of WC in WCS.  */
  26 wchar_t *
  27 WCSCHR (const wchar_t *wcs, const wchar_t wc)
  28 {
  29   wchar_t *dest = NULL;
  30
  31 #define ITERATION(index)                \
  32   ({                                    \
  33     if (*wcs == wc)                     \
  34       dest = (wchar_t*) wcs;            \
  35     dest == NULL && *wcs++ != L'\0';    \
  36   })
  37
  38 #ifndef UNROLL_NTIMES
  39 # define UNROLL_NTIMES 1
  40 #endif
  41
  42   while (1)
  43     UNROLL_REPEAT (UNROLL_NTIMES, ITERATION);
  44
  45   return dest;
  46 }
  47 libc_hidden_def (__wcschr)
  48 weak_alias (__wcschr, wcschr)
  49 libc_hidden_weak (wcschr)