xref: /freebsd/stand/libsa/gets.c (revision 2008043f386721d58158e37e0d7e50df8095942d)
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 #include "stand.h"
36 
37 /* gets() with constrained input length */
38 
39 void
40 ngets(char *buf, int n)
41 {
42     int c;
43     char *lp;
44 
45     for (lp = buf;;) {
46 	c = getchar();
47 	if (c == -1)
48 		break;
49 	switch (c & 0177) {
50 	case '\n':
51 	case '\r':
52 	    *lp = '\0';
53 	    putchar('\n');
54 	    return;
55 	case '\b':
56 	case '\177':
57 	    if (lp > buf) {
58 		lp--;
59 		putchar('\b');
60 		putchar(' ');
61 		putchar('\b');
62 	    }
63 	    break;
64 	case 'r'&037: {
65 	    char *p;
66 
67 	    putchar('\n');
68 	    for (p = buf; p < lp; ++p)
69 		putchar(*p);
70 	    break;
71 	}
72 	case 'u'&037:
73 	case 'w'&037:
74 	    lp = buf;
75 	    putchar('\n');
76 	    break;
77 	default:
78 	    if ((n < 1) || ((lp - buf) < n - 1)) {
79 		*lp++ = c;
80 		putchar(c);
81 	    }
82 	}
83     }
84     /*NOTREACHED*/
85 }
86 
87 int
88 fgetstr(char *buf, int size, int fd)
89 {
90     char	c;
91     int		err, len;
92 
93     size--;	/* leave space for terminator */
94     len = 0;
95     while (size != 0) {
96 	err = read(fd, &c, sizeof(c));
97 	if (err < 0)		/* read error */
98 	    return(-1);
99 	if (err == 0) {		/* EOF */
100 	    if (len == 0)
101 		return(-1);	/* nothing to read */
102 	    break;
103 	}
104 	if ((c == '\r') ||	/* line terminators */
105 	    (c == '\n'))
106 	    break;
107 	*buf++ = c;		/* keep char */
108 	size--;
109 	len++;
110     }
111     *buf = 0;
112     return(len);
113 }
114 
115