[mirror_frr.git] / lib / strlcpy.c

/* Copy a null-terminated string to a fixed-size buffer, with length checking.
 * Copyright (C) 2016 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
 * <http://www.gnu.org/licenses/>.
 */

/* adapted for Quagga from glibc patch submission originally from
 * Florian Weimer <fweimer@redhat.com>, 2016-05-18 */

#include <string.h>

#include "config.h"

#ifndef HAVE_STRLCPY
#undef strlcpy

size_t strlcpy(char *__restrict dest, const char *__restrict src, size_t size);

size_t strlcpy(char *__restrict dest, const char *__restrict src, size_t size)
{
	size_t src_length = strlen(src);

	if (__builtin_expect(src_length >= size, 0)) {
		if (size > 0) {
			/* Copy the leading portion of the string.  The last
			   character is subsequently overwritten with the NUL
			   terminator, but the destination size is usually a
			   multiple of a small power of two, so writing it twice
			   should be more efficient than copying an odd number
			   of
			   bytes.  */
			memcpy(dest, src, size);
			dest[size - 1] = '\0';
		}
	} else
		/* Copy the string and its terminating NUL character.  */
		memcpy(dest, src, src_length + 1);
	return src_length;
}
#endif /* HAVE_STRLCPY */
Commit	Line	Data
c5d9d3bb	1	/* Copy a null-terminated string to a fixed-size buffer, with length checking.
896014f4 DL	2	* Copyright (C) 2016 Free Software Foundation, Inc.
	3	* This file is part of the GNU C Library.
	4	*
	5	* The GNU C Library is free software; you can redistribute it and/or
	6	* modify it under the terms of the GNU Lesser General Public
	7	* License as published by the Free Software Foundation; either
	8	* version 2.1 of the License, or (at your option) any later version.
	9	*
	10	* The GNU C Library is distributed in the hope that it will be useful,
	11	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	12	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	13	* Lesser General Public License for more details.
	14	*
	15	* You should have received a copy of the GNU Lesser General Public
	16	* License along with the GNU C Library; if not, see
d62a17ae	17	* <http://www.gnu.org/licenses/>.
896014f4	18	*/
c5d9d3bb DL	19
	20	/* adapted for Quagga from glibc patch submission originally from
	21	* Florian Weimer <fweimer@redhat.com>, 2016-05-18 */
	22
	23	#include <string.h>
	24
	25	#include "config.h"
	26
	27	#ifndef HAVE_STRLCPY
	28	#undef strlcpy
	29
d62a17ae	30	size_t strlcpy(char __restrict dest, const char __restrict src, size_t size);
c5d9d3bb	31
d62a17ae	32	size_t strlcpy(char __restrict dest, const char __restrict src, size_t size)
c5d9d3bb	33	{
d62a17ae	34	size_t src_length = strlen(src);
c5d9d3bb	35
d62a17ae	36	if (__builtin_expect(src_length >= size, 0)) {
	37	if (size > 0) {
	38	/* Copy the leading portion of the string. The last
	39	character is subsequently overwritten with the NUL
	40	terminator, but the destination size is usually a
	41	multiple of a small power of two, so writing it twice
	42	should be more efficient than copying an odd number
	43	of
	44	bytes. */
	45	memcpy(dest, src, size);
	46	dest[size - 1] = '\0';
	47	}
	48	} else
	49	/* Copy the string and its terminating NUL character. */
	50	memcpy(dest, src, src_length + 1);
	51	return src_length;
c5d9d3bb DL	52	}
c5d9d3bb DL	53	#endif /* HAVE_STRLCPY */