lib/libstand/gets.c

   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. All advertising materials mentioning features or use of this software
  17  *    must display the following acknowledgement:
  18  *      This product includes software developed by the University of
  19  *      California, Berkeley and its contributors.
  20  * 4. Neither the name of the University nor the names of its contributors
  21  *    may be used to endorse or promote products derived from this software
  22  *    without specific prior written permission.
  23  *
  24  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  34  * SUCH DAMAGE.
  35  *
  36  *      @(#)gets.c      8.1 (Berkeley) 6/11/93
  37  */
  38
  39 #include "stand.h"
  40
  41 /* gets() with constrained input length */
  42
  43 void
  44 ngets(char *buf, int n)
  45 {
  46     int c;
  47     char *lp;
  48
  49     for (lp = buf;;)
  50         switch (c = getchar() & 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)) {
  80                 *lp++ = c;
  81                 putchar(c);
  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