gets.c revision 338077 
1/*	$NetBSD: gets.c,v 1.6 1995/10/11 21:16:57 pk Exp $	*/
2
3/*-
4 * Copyright (c) 1993
5 *	The Regents of the University of California.  All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 * 4. Neither the name of the University nor the names of its contributors
16 *    may be used to endorse or promote products derived from this software
17 *    without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 *
31 *	@(#)gets.c	8.1 (Berkeley) 6/11/93
32 */
33
34#include <sys/cdefs.h>
35__FBSDID("$FreeBSD: stable/11/stand/libsa/gets.c 338077 2018-08-20 00:49:06Z kevans $");
36
37#include "stand.h"
38
39/* gets() with constrained input length */
40
41void
42ngets(char *buf, int n)
43{
44    int c;
45    char *lp;
46
47    for (lp = buf;;) {
48	c = getchar();
49	if (c == -1)
50		break;
51	switch (c & 0177) {
52	case '\n':
53	case '\r':
54	    *lp = '\0';
55	    putchar('\n');
56	    return;
57	case '\b':
58	case '\177':
59	    if (lp > buf) {
60		lp--;
61		putchar('\b');
62		putchar(' ');
63		putchar('\b');
64	    }
65	    break;
66	case 'r'&037: {
67	    char *p;
68
69	    putchar('\n');
70	    for (p = buf; p < lp; ++p)
71		putchar(*p);
72	    break;
73	}
74	case 'u'&037:
75	case 'w'&037:
76	    lp = buf;
77	    putchar('\n');
78	    break;
79	default:
80	    if ((n < 1) || ((lp - buf) < n - 1)) {
81		*lp++ = c;
82		putchar(c);
83	    }
84	}
85    }
86    /*NOTREACHED*/
87}
88
89int
90fgetstr(char *buf, int size, int fd)
91{
92    char	c;
93    int		err, len;
94
95    size--;	/* leave space for terminator */
96    len = 0;
97    while (size != 0) {
98	err = read(fd, &c, sizeof(c));
99	if (err < 0)		/* read error */
100	    return(-1);
101	if (err == 0) {		/* EOF */
102	    if (len == 0)
103		return(-1);	/* nothing to read */
104	    break;
105	}
106	if ((c == '\r') ||	/* line terminators */
107	    (c == '\n'))
108	    break;
109	*buf++ = c;		/* keep char */
110	size--;
111	len++;
112    }
113    *buf = 0;
114    return(len);
115}
116
117