Updated to fedora-glibc-20080612T1619
[glibc.git] / debug / strcat_chk.c
blobb3fb3470b7fd22eb2797951d8d4fecdbaf311580
1 /* Copyright (C) 1991, 1997, 2003, 2004 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
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.
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.
14 You should have received a copy of the GNU Lesser General Public
15 License along with the GNU C Library; if not, write to the Free
16 Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
17 02111-1307 USA. */
19 #include <string.h>
20 #include <memcopy.h>
23 /* Append SRC on the end of DEST. */
24 char *
25 __strcat_chk (dest, src, destlen)
26 char *dest;
27 const char *src;
28 size_t destlen;
30 char *s1 = dest;
31 const char *s2 = src;
32 reg_char c;
34 /* Find the end of the string. */
37 if (__builtin_expect (destlen-- == 0, 0))
38 __chk_fail ();
39 c = *s1++;
41 while (c != '\0');
43 /* Make S1 point before the next character, so we can increment
44 it while memory is read (wins on pipelined cpus). */
45 ++destlen;
46 s1 -= 2;
50 if (__builtin_expect (destlen-- == 0, 0))
51 __chk_fail ();
52 c = *s2++;
53 *++s1 = c;
55 while (c != '\0');
57 return dest;