/* Copyright (C) 1991, 1997, 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
#include
char *
__strncat_chk (s1, s2, n, s1len)
char *s1;
const char *s2;
size_t n;
size_t s1len;
{
reg_char c;
char *s = s1;
/* Find the end of S1. */
do
{
if (__builtin_expect (s1len-- == 0, 0))
__chk_fail ();
c = *s1++;
}
while (c != '\0');
/* Make S1 point before next character, so we can increment
it while memory is read (wins on pipelined cpus). */
++s1len;
s1 -= 2;
if (n >= 4)
{
size_t n4 = n >> 2;
do
{
if (__builtin_expect (s1len-- == 0, 0))
__chk_fail ();
c = *s2++;
*++s1 = c;
if (c == '\0')
return s;
if (__builtin_expect (s1len-- == 0, 0))
__chk_fail ();
c = *s2++;
*++s1 = c;
if (c == '\0')
return s;
if (__builtin_expect (s1len-- == 0, 0))
__chk_fail ();
c = *s2++;
*++s1 = c;
if (c == '\0')
return s;
if (__builtin_expect (s1len-- == 0, 0))
__chk_fail ();
c = *s2++;
*++s1 = c;
if (c == '\0')
return s;
} while (--n4 > 0);
n &= 3;
}
while (n > 0)
{
if (__builtin_expect (s1len-- == 0, 0))
__chk_fail ();
c = *s2++;
*++s1 = c;
if (c == '\0')
return s;
n--;
}
if (c != '\0')
{
if (__builtin_expect (s1len-- == 0, 0))
__chk_fail ();
*++s1 = '\0';
}
return s;
}