1 /*        $NetBSD: gets.c,v 1.15 2019/03/31 20:08:45 christos 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 "stand.h"
35 
36 #if 0 /* harmful */
37 void
38 gets(char *buf)
39 {
40           kgets(buf, (size_t)-1);
41 }
42 #endif
43 
44 void
kgets(char * buf,size_t size)45 kgets(char *buf, size_t size)
46 {
47           int c;
48           char *lp;
49 
50           for (lp = buf;;) {
51                     if ((size_t)(lp - buf) == size) {
52                               lp--;
53                               *lp = '\0';
54                               return;
55                     }
56                     switch (c = getchar() & 0177) {
57                     case '\n':
58                     case '\r':
59                               *lp = '\0';
60                               putchar('\n');
61                               return;
62                     case '\b':
63                     case '\177':
64                               if (lp > buf) {
65                                         lp--;
66                                         putchar('\b');
67                                         putchar(' ');
68                                         putchar('\b');
69                               }
70                               break;
71 #if HASH_ERASE
72                     case '#':
73                               if (lp > buf)
74                                         --lp;
75                               break;
76 #endif
77                     case 'r' & 037: {
78                               char *p;
79 
80                               putchar('\n');
81                               for (p = buf; p < lp; ++p)
82                                         putchar(*p);
83                               break;
84                     }
85 #if AT_ERASE
86                     case '@':
87 #endif
88                     case 'u' & 037:
89                     case 'w' & 037:
90                               lp = buf;
91                               putchar('\n');
92                               break;
93                     default:
94                               *lp++ = c;
95                               putchar(c);
96                               break;
97                     }
98           }
99           /*NOTREACHED*/
100 }
101