libc/string/memchr.c

   1 /*
   2  *  ZeX/OS
   3  *  Copyright (C) 2008  Tomas 'ZeXx86' Jedrzejek (zexx86@zexos.org)
   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 <http://www.gnu.org/licenses/>.
  17  */
  18
  19
  20 #include <string.h> /* size_t */
  21
  22 void *memchr (void const *buf, int c, size_t len)
  23 {
  24         size_t i;
  25         const unsigned char *b = buf;
  26         unsigned char x = (c & 0xff);
  27
  28         for (i= 0; i < len; i ++) {
  29                 if (b[i] == x)
  30                         return (void *) (b + i);
  31         }
  32
  33         return 0;
  34 }