gets.c revision 1.13 
1/*	$NetBSD: gets.c,v 1.13 1999/09/20 04:39:30 lukem 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. All advertising materials mentioning features or use of this software
19 *    must display the following acknowledgement:
20 *	This product includes software developed by the University of
21 *	California, Berkeley and its contributors.
22 * 4. Neither the name of the University nor the names of its contributors
23 *    may be used to endorse or promote products derived from this software
24 *    without specific prior written permission.
25 *
26 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
29 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36 * SUCH DAMAGE.
37 */
38
39#include <sys/cdefs.h>
40#if defined(LIBC_SCCS) && !defined(lint)
41#if 0
42static char sccsid[] = "@(#)gets.c	8.1 (Berkeley) 6/4/93";
43#else
44__RCSID("$NetBSD: gets.c,v 1.13 1999/09/20 04:39:30 lukem Exp $");
45#endif
46#endif /* LIBC_SCCS and not lint */
47
48#include <assert.h>
49#include <errno.h>
50#include <stdio.h>
51#include "reentrant.h"
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