string/strchr.c

   1 /* Copyright (C) 1991-2024 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 <string.h>
  19
  20 #undef strchr
  21 #undef index
  22
  23 #ifdef STRCHR
  24 # define strchr STRCHR
  25 #endif
  26
  27 /* Find the first occurrence of C in S.  */
  28 char *
  29 strchr (const char *s, int c_in)
  30 {
  31   char *r = __strchrnul (s, c_in);
  32   return (*(unsigned char *)r == (unsigned char)c_in) ? r : NULL;
  33 }
  34 #ifndef STRCHR
  35 weak_alias (strchr, index)
  36 libc_hidden_builtin_def (strchr)
  37 #endif