summary refs log tree commit diff
path: root/sysdeps/generic/strcpy_chk.c
blob: 5c1ae44cd078329b9ba42ce3ed80719864012aca (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
/* Copyright (C) 1991, 1997, 2000, 2003, 2004 Free Software Foundation, Inc.
   This file is part of the GNU C Library.

   The GNU C Library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Lesser General Public
   License as published by the Free Software Foundation; either
   version 2.1 of the License, or (at your option) any later version.

   The GNU C Library is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   Lesser General Public License for more details.

   You should have received a copy of the GNU Lesser General Public
   License along with the GNU C Library; if not, write to the Free
   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
   02111-1307 USA.  */

#include <stddef.h>
#include <string.h>
#include <memcopy.h>

#undef strcpy

/* Copy SRC to DEST with checking of destination buffer overflow.  */
char *
__strcpy_chk (dest, src, destlen)
     char *dest;
     const char *src;
     size_t destlen;
{
  reg_char c;
  char *s = (char *) src;
  const ptrdiff_t off = dest - s - 1;

  do
    {
      if (__builtin_expect (destlen-- == 0, 0))
	__chk_fail ();
      c = *s++;
      s[off] = c;
    }
  while (c != '\0');

  return dest;
}