sysdeps/generic/memccpy.c

   1 /* Copyright (C) 1991, 1995 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 Library General Public License as
   6 published by the Free Software Foundation; either version 2 of the
   7 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 Library General Public License for more details.
  13
  14 You should have received a copy of the GNU Library General Public
  15 License along with the GNU C Library; see the file COPYING.LIB.  If
  16 not, write to the Free Software Foundation, Inc., 675 Mass Ave,
  17 Cambridge, MA 02139, USA.  */
  18
  19 #include <ansidecl.h>
  20 #include <stddef.h>     /* For size_t and NULL. */
  21
  22
  23 /*
  24  * Copy no more than N bytes of SRC to DEST, stopping when C is found.
  25  * Return the position in DEST one byte past where C was copied,
  26  * or NULL if C was not found in the first N bytes of SRC.
  27  */
  28 PTR
  29 DEFUN(__memccpy, (dest, src, c, n),
  30       PTR dest AND CONST PTR src AND int c AND size_t n)
  31 {
  32   register CONST char *s = src;
  33   register char *d = dest;
  34   register CONST int x = (unsigned char) c;
  35   register size_t i = n;
  36
  37   while (i-- > 0)
  38     if ((*d++ = *s++) == x)
  39       return d;
  40
  41   return NULL;
  42 }
  43
  44 weak_alias (__memccpy, memccpy)