xref: /dflybsd-src/contrib/gcc-8.0/libssp/strcat-chk.c (revision 38fd149817dfbff97799f62fcb70be98c4e32523)
1*38fd1498Szrj /* Checking strcat.
2*38fd1498Szrj    Copyright (C) 1991-2018 Free Software Foundation, Inc.
3*38fd1498Szrj 
4*38fd1498Szrj This file is part of GCC.
5*38fd1498Szrj 
6*38fd1498Szrj GCC is free software; you can redistribute it and/or modify it under
7*38fd1498Szrj the terms of the GNU General Public License as published by the Free
8*38fd1498Szrj Software Foundation; either version 3, or (at your option) any later
9*38fd1498Szrj version.
10*38fd1498Szrj 
11*38fd1498Szrj In addition to the permissions in the GNU General Public License, the
12*38fd1498Szrj Free Software Foundation gives you unlimited permission to link the
13*38fd1498Szrj compiled version of this file into combinations with other programs,
14*38fd1498Szrj and to distribute those combinations without any restriction coming
15*38fd1498Szrj from the use of this file.  (The General Public License restrictions
16*38fd1498Szrj do apply in other respects; for example, they cover modification of
17*38fd1498Szrj the file, and distribution when not linked into a combine
18*38fd1498Szrj executable.)
19*38fd1498Szrj 
20*38fd1498Szrj GCC is distributed in the hope that it will be useful, but WITHOUT ANY
21*38fd1498Szrj WARRANTY; without even the implied warranty of MERCHANTABILITY or
22*38fd1498Szrj FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
23*38fd1498Szrj for more details.
24*38fd1498Szrj 
25*38fd1498Szrj Under Section 7 of GPL version 3, you are granted additional
26*38fd1498Szrj permissions described in the GCC Runtime Library Exception, version
27*38fd1498Szrj 3.1, as published by the Free Software Foundation.
28*38fd1498Szrj 
29*38fd1498Szrj You should have received a copy of the GNU General Public License and
30*38fd1498Szrj a copy of the GCC Runtime Library Exception along with this program;
31*38fd1498Szrj see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
32*38fd1498Szrj <http://www.gnu.org/licenses/>.  */
33*38fd1498Szrj 
34*38fd1498Szrj 
35*38fd1498Szrj #include "config.h"
36*38fd1498Szrj #include <ssp/ssp.h>
37*38fd1498Szrj #ifdef HAVE_STRING_H
38*38fd1498Szrj # include <string.h>
39*38fd1498Szrj #endif
40*38fd1498Szrj 
41*38fd1498Szrj extern void __chk_fail (void) __attribute__((__noreturn__));
42*38fd1498Szrj 
43*38fd1498Szrj char *
__strcat_chk(char * __restrict__ dest,const char * __restrict__ src,size_t slen)44*38fd1498Szrj __strcat_chk (char *__restrict__ dest, const char *__restrict__ src,
45*38fd1498Szrj               size_t slen)
46*38fd1498Szrj {
47*38fd1498Szrj   char *s1 = dest;
48*38fd1498Szrj   const char *s2 = src;
49*38fd1498Szrj   char c;
50*38fd1498Szrj 
51*38fd1498Szrj   do
52*38fd1498Szrj     {
53*38fd1498Szrj       if (slen-- == 0)
54*38fd1498Szrj         __chk_fail ();
55*38fd1498Szrj       c = *s1++;
56*38fd1498Szrj     }
57*38fd1498Szrj   while (c != '\0');
58*38fd1498Szrj 
59*38fd1498Szrj   ++slen;
60*38fd1498Szrj   s1 -= 2;
61*38fd1498Szrj 
62*38fd1498Szrj   do
63*38fd1498Szrj     {
64*38fd1498Szrj       if (slen-- == 0)
65*38fd1498Szrj         __chk_fail ();
66*38fd1498Szrj       c = *s2++;
67*38fd1498Szrj       *++s1 = c;
68*38fd1498Szrj     }
69*38fd1498Szrj   while (c != '\0');
70*38fd1498Szrj 
71*38fd1498Szrj   return dest;
72*38fd1498Szrj }
73