1/* $NetBSD: gets.c,v 1.5 2016/06/11 06:49:46 dholland 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/* 37 * This implementation assumes that getchar() does echo, because 38 * on some machines, it is hard to keep echo from being done. 39 * Those that need it can do echo in their getchar() function. 40 * 41 * Yes, the code below will echo CR, DEL, and other control chars, 42 * but sending CR or DEL here is harmless. All the other editing 43 * characters will be followed by a newline, so it doesn't matter. 44 * (Most terminals will not show them anyway.) 45 */ 46 47void 48kgets(char *buf, size_t size) 49{ 50 int c; 51 char *lp; 52 53top: 54 lp = buf; 55 56 for (;;) { 57 if (lp - buf == size) { 58 lp--; 59 *lp = '\0'; 60 return; 61 } 62 c = getchar() & 0177; 63 64#ifdef GETS_MUST_ECHO /* Preserved in case someone wants it... */ 65 putchar(c); 66#endif 67 68 switch (c) { 69 70 default: 71 *lp++ = c; 72 continue; 73 74 case '\177': 75 putchar('\b'); 76 /* fall through */ 77 case '\b': 78 putchar(' '); 79 putchar('\b'); 80 /* fall through */ 81 case '#': 82 if (lp > buf) 83 lp--; 84 continue; 85 86#ifdef GETS_REPRINT 87 /* 88 * This is not very useful in a boot program. 89 * (It costs you 52 bytes on m68k, gcc -O3). 90 */ 91 case 'r'&037: { 92 char *p; 93 94 putchar('\n'); 95 for (p = buf; p < lp; ++p) 96 putchar(*p); 97 continue; 98 } 99#endif 100 101 case '@': 102 case 'u'&037: 103 case 'w'&037: 104 putchar('\n'); 105 goto top; 106 107 case '\r': 108 putchar('\n'); 109 /* fall through */ 110 case '\n': 111 *lp = '\0'; 112 return; 113 114 } /* switch */ 115 } 116 /*NOTREACHED*/ 117} 118