xref: /freebsd/stand/libsa/gets.c (revision bdd1243df58e60e85101c09001d9812a789b6bc4)
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  * 3. 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("$FreeBSD$");
36 
37 #include "stand.h"
38 
39 /* gets() with constrained input length */
40 
41 void
42 ngets(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 
89 int
90 fgetstr(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