gets.c revision 1.16 
1/*	$NetBSD: gets.c,v 1.16 2007/06/03 17:39:26 christos Exp $	*/
2
3/*-
4 * Copyright (c) 1990, 1993
5 *	The Regents of the University of California.  All rights reserved.
6 *
7 * This code is derived from software contributed to Berkeley by
8 * Chris Torek.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 *    notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 *    notice, this list of conditions and the following disclaimer in the
17 *    documentation and/or other materials provided with the distribution.
18 * 3. Neither the name of the University nor the names of its contributors
19 *    may be used to endorse or promote products derived from this software
20 *    without specific prior written permission.
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 * SUCH DAMAGE.
33 */
34
35#include <sys/cdefs.h>
36#if defined(LIBC_SCCS) && !defined(lint)
37#if 0
38static char sccsid[] = "@(#)gets.c	8.1 (Berkeley) 6/4/93";
39#else
40__RCSID("$NetBSD: gets.c,v 1.16 2007/06/03 17:39:26 christos Exp $");
41#endif
42#endif /* LIBC_SCCS and not lint */
43
44#include <assert.h>
45#include <errno.h>
46#include <stdio.h>
47#include "reentrant.h"
48#include "local.h"
49#ifdef _FORTIFY_SOURCE
50#undef gets
51#endif
52
53__warn_references(gets, "warning: this program uses gets(), which is unsafe.")
54
55char *
56gets(buf)
57	char *buf;
58{
59	int c;
60	char *s;
61
62	_DIAGASSERT(buf != NULL);
63
64	FLOCKFILE(stdin);
65	for (s = buf; (c = getchar_unlocked()) != '\n'; ) {
66		if (c == EOF) {
67			if (s == buf) {
68				FUNLOCKFILE(stdin);
69				return (NULL);
70			} else {
71				break;
72			}
73		} else {
74			*s++ = c;
75		}
76	}
77	*s = 0;
78	FUNLOCKFILE(stdin);
79	return (buf);
80}
81