1 /* $NetBSD: gets.c,v 1.6 1995/10/11 21:16:57 pk Exp $ */
2 /* $DragonFly: src/lib/libstand/gets.c,v 1.2 2004/10/25 19:38:45 drhodus Exp $ */
3
4 /*-
5 * Copyright (c) 1993
6 * The Regents of the University of California. All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. Neither the name of the University nor the names of its contributors
17 * may be used to endorse or promote products derived from this software
18 * without specific prior written permission.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 * SUCH DAMAGE.
31 *
32 * @(#)gets.c 8.1 (Berkeley) 6/11/93
33 */
34
35 #include "stand.h"
36
37 /* gets() with constrained input length */
38
39 void
ngets(char * buf,int n)40 ngets(char *buf, int n)
41 {
42 int c;
43 char *lp;
44
45 for (lp = buf;;)
46 switch (c = getchar() & 0177) {
47 case '\n':
48 case '\r':
49 *lp = '\0';
50 putchar('\n');
51 return;
52 case '\b':
53 case '\177':
54 if (lp > buf) {
55 lp--;
56 putchar('\b');
57 putchar(' ');
58 putchar('\b');
59 }
60 break;
61 case 'r'&037: {
62 char *p;
63
64 putchar('\n');
65 for (p = buf; p < lp; ++p)
66 putchar(*p);
67 break;
68 }
69 case 'u'&037:
70 case 'w'&037:
71 lp = buf;
72 putchar('\n');
73 break;
74 default:
75 if ((n < 1) || ((lp - buf) < n)) {
76 *lp++ = c;
77 putchar(c);
78 }
79 }
80 /*NOTREACHED*/
81 }
82
83 int
fgetstr(char * buf,int size,int fd)84 fgetstr(char *buf, int size, int fd)
85 {
86 char c;
87 int err, len;
88
89 size--; /* leave space for terminator */
90 len = 0;
91 while (size != 0) {
92 err = read(fd, &c, sizeof(c));
93 if (err < 0) /* read error */
94 return(-1);
95 if (err == 0) { /* EOF */
96 if (len == 0)
97 return(-1); /* nothing to read */
98 break;
99 }
100 if ((c == '\r') || /* line terminators */
101 (c == '\n'))
102 break;
103 *buf++ = c; /* keep char */
104 size--;
105 len++;
106 }
107 *buf = 0;
108 return(len);
109 }
110
111 char *
fgets(char * buf,int size,int fd)112 fgets(char *buf, int size, int fd)
113 {
114 char c, *p;
115 int err, len;
116
117 p = buf;
118 size--; /* leave space for terminator */
119 len = 0;
120 while (size != 0) {
121 err = read(fd, &c, sizeof(c));
122 if (err < 0) /* read error */
123 return(NULL);
124 if (err == 0) { /* EOF */
125 if (len == 0)
126 return(NULL); /* nothing to read */
127 break;
128 }
129 *p++ = c; /* keep char */
130 size--;
131 len++;
132 if ((c == '\r') || /* line terminators */
133 (c == '\n'))
134 break;
135 }
136 *p = 0;
137 return(buf);
138 }
139