xref: /illumos-gate/usr/src/boot/libsa/gets.c (revision ddb365bfc9e868ad24ccdcb0dc91af18b10df082)
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 
36 #include "stand.h"
37 
38 /* gets() with constrained input length */
39 
40 void
41 ngets(char *buf, int n)
42 {
43 	int c;
44 	char *lp;
45 
46 	for (lp = buf; ; ) {
47 		c = getchar();
48 		if (c == -1)
49 			break;
50 		switch (c & 0177) {
51 		case '\n':
52 		case '\r':
53 			*lp = '\0';
54 			putchar('\n');
55 			return;
56 		case '\b':
57 		case '\177':
58 			if (lp > buf) {
59 				lp--;
60 				putchar('\b');
61 				putchar(' ');
62 				putchar('\b');
63 			}
64 			break;
65 		case 'r' & 037: {
66 			char *p;
67 
68 			putchar('\n');
69 			for (p = buf; p < lp; ++p)
70 				putchar(*p);
71 			break;
72 		}
73 		case 'u' & 037:
74 		case 'w' & 037:
75 			lp = buf;
76 			putchar('\n');
77 			break;
78 		default:
79 			if ((n < 1) || ((lp - buf) < n - 1)) {
80 				*lp++ = c;
81 				putchar(c);
82 			}
83 		}
84 	}
85 	/*NOTREACHED*/
86 }
87 
88 int
89 fgetstr(char *buf, int size, int fd)
90 {
91 	char	c;
92 	int	err, len;
93 
94 	size--;	/* leave space for terminator */
95 	len = 0;
96 	while (size != 0) {
97 		err = read(fd, &c, sizeof (c));
98 		if (err < 0)		/* read error */
99 			return (-1);
100 		if (err == 0) {		/* EOF */
101 			if (len == 0)
102 				return (-1);	/* nothing to read */
103 			break;
104 		}
105 		if ((c == '\r') ||	/* line terminators */
106 		    (c == '\n'))
107 			break;
108 		*buf++ = c;		/* keep char */
109 		size--;
110 		len++;
111 	}
112 	*buf = 0;
113 	return (len);
114 }
115