glibc/debug/strlcat_chk.c
Florian Weimer 454a20c875 Implement strlcpy and strlcat [BZ #178]
These functions are about to be added to POSIX, under Austin Group
issue 986.

The fortified strlcat implementation does not raise SIGABRT if the
destination buffer does not contain a null terminator, it just
inherits the non-failing regular strlcat behavior.

Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
2023-06-14 18:10:08 +02:00

32 lines
1.1 KiB
C

/* Fortified version of strlcat.
Copyright (C) 2023 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>
/* Check that the user-supplied size does not exceed the
compiler-determined size, and then forward to strlcat. */
size_t
__strlcat_chk (char *__restrict s1, const char *__restrict s2,
size_t n, size_t s1len)
{
if (__glibc_unlikely (s1len < n))
__chk_fail ();
return __strlcat (s1, s2, n);
}