glibc/debug/strncat_chk.c
Paul Eggert 581c785bf3 Update copyright dates with scripts/update-copyrights
I used these shell commands:

../glibc/scripts/update-copyrights $PWD/../gnulib/build-aux/update-copyright
(cd ../glibc && git commit -am"[this commit message]")

and then ignored the output, which consisted lines saying "FOO: warning:
copyright statement not found" for each of 7061 files FOO.

I then removed trailing white space from math/tgmath.h,
support/tst-support-open-dev-null-range.c, and
sysdeps/x86_64/multiarch/strlen-vec.S, to work around the following
obscure pre-commit check failure diagnostics from Savannah.  I don't
know why I run into these diagnostics whereas others evidently do not.

remote: *** 912-#endif
remote: *** 913:
remote: *** 914-
remote: *** error: lines with trailing whitespace found
...
remote: *** error: sysdeps/unix/sysv/linux/statx_cp.c: trailing lines
2022-01-01 11:40:24 -08:00

96 lines
2 KiB
C

/* Copyright (C) 1991-2022 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, see
<https://www.gnu.org/licenses/>. */
#include <string.h>
#include <memcopy.h>
char *
__strncat_chk (char *s1, const char *s2, size_t n, size_t s1len)
{
char c;
char *s = s1;
/* Find the end of S1. */
do
{
if (__glibc_unlikely (s1len-- == 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 (__glibc_unlikely (s1len-- == 0))
__chk_fail ();
c = *s2++;
*++s1 = c;
if (c == '\0')
return s;
if (__glibc_unlikely (s1len-- == 0))
__chk_fail ();
c = *s2++;
*++s1 = c;
if (c == '\0')
return s;
if (__glibc_unlikely (s1len-- == 0))
__chk_fail ();
c = *s2++;
*++s1 = c;
if (c == '\0')
return s;
if (__glibc_unlikely (s1len-- == 0))
__chk_fail ();
c = *s2++;
*++s1 = c;
if (c == '\0')
return s;
} while (--n4 > 0);
n &= 3;
}
while (n > 0)
{
if (__glibc_unlikely (s1len-- == 0))
__chk_fail ();
c = *s2++;
*++s1 = c;
if (c == '\0')
return s;
n--;
}
if (c != '\0')
{
if (__glibc_unlikely (s1len-- == 0))
__chk_fail ();
*++s1 = '\0';
}
return s;
}