NetBSD/lib/libc/ssp/gets_chk.c

75 lines
2.2 KiB
C

/* $NetBSD: gets_chk.c,v 1.6 2010/01/17 23:13:32 wiz Exp $ */
/*-
* Copyright (c) 2006 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Christos Zoulas.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__RCSID("$NetBSD: gets_chk.c,v 1.6 2010/01/17 23:13:32 wiz Exp $");
/*LINTLIBRARY*/
#include <ssp/ssp.h>
#include <stdio.h>
#include <string.h>
#include <limits.h>
#include <stdlib.h>
#include <ssp/stdio.h>
#undef gets
char *
__gets_chk(char * __restrict buf, size_t slen)
{
char *abuf;
size_t len;
if (slen >= (size_t)INT_MAX)
return gets(buf);
if ((abuf = malloc(slen + 1)) == NULL)
return gets(buf);
if (fgets(abuf, (int)(slen + 1), stdin) == NULL) {
free(abuf);
return NULL;
}
len = strlen(abuf);
if (len > 0 && abuf[len - 1] == '\n')
--len;
if (len >= slen)
__chk_fail();
(void)memcpy(buf, abuf, len);
buf[len] = '\0';
free(abuf);
return buf;
}