usr/src/cmd/vi/misc/fold.c

   1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License, Version 1.0 only
   6  * (the "License").  You may not use this file except in compliance
   7  * with the License.
   8  *
   9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
  10  * or http://www.opensolaris.org/os/licensing.
  11  * See the License for the specific language governing permissions
  12  * and limitations under the License.
  13  *
  14  * When distributing Covered Code, include this CDDL HEADER in each
  15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  16  * If applicable, add the following below this CDDL HEADER, with the
  17  * fields enclosed by brackets "[]" replaced with your own identifying
  18  * information: Portions Copyright [yyyy] [name of copyright owner]
  19  *
  20  * CDDL HEADER END
  21  */
  22 /*
  23  * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
  24  * Use is subject to license terms.
  25  */
  26
  27 /*      Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */
  28 /*        All Rights Reserved   */
  29
  30 /*
  31  * University Copyright- Copyright (c) 1982, 1986, 1988
  32  * The Regents of the University of California
  33  * All Rights Reserved
  34  *
  35  * University Acknowledgment- Portions of this document are derived from
  36  * software developed by the University of California, Berkeley, and its
  37  * contributors.
  38  */
  39
  40 #pragma ident   "%Z%%M% %I%     %E% SMI"
  41
  42 #include <stdio.h>
  43 /*
  44  * fold - fold long lines for finite output devices
  45  *
  46  */
  47
  48 int     fold =  80;
  49
  50 void putch(int c);
  51
  52 int
  53 main(int argc, char *argv[])
  54 {
  55         int c;
  56         FILE *f;
  57         char obuf[BUFSIZ];
  58
  59         argc--, argv++;
  60         setbuf(stdout, obuf);
  61         if (argc > 0 && argv[0][0] == '-') {
  62                 fold = 0;
  63                 argv[0]++;
  64                 while (*argv[0] >= '0' && *argv[0] <= '9')
  65                         fold *= 10, fold += *argv[0]++ - '0';
  66                 if (*argv[0]) {
  67                         printf("Bad number for fold\n");
  68                         exit(1);
  69                 }
  70                 argc--, argv++;
  71         }
  72         do {
  73                 if (argc > 0) {
  74                         if (freopen(argv[0], "r", stdin) == NULL) {
  75                                 perror(argv[0]);
  76                                 exit(1);
  77                         }
  78                         argc--, argv++;
  79                 }
  80                 for (;;) {
  81                         c = getc(stdin);
  82                         if (c == -1)
  83                                 break;
  84                         putch(c);
  85                 }
  86         } while (argc > 0);
  87         return (0);
  88 }
  89
  90 int     col;
  91
  92 void
  93 putch(int c)
  94 {
  95         int ncol;
  96
  97         switch (c) {
  98                 case '\n':
  99                         ncol = 0;
 100                         break;
 101                 case '\t':
 102                         ncol = (col + 8) &~ 7;
 103                         break;
 104                 case '\b':
 105                         ncol = col ? col - 1 : 0;
 106                         break;
 107                 case '\r':
 108                         ncol = 0;
 109                         break;
 110                 default:
 111                         ncol = col + 1;
 112         }
 113         if (ncol > fold)
 114                 putchar('\n'), col = 0;
 115         putchar(c);
 116         switch (c) {
 117                 case '\n':
 118                         col = 0;
 119                         break;
 120                 case '\t':
 121                         col += 8;
 122                         col &= ~7;
 123                         break;
 124                 case '\b':
 125                         if (col)
 126                                 col--;
 127                         break;
 128                 case '\r':
 129                         col = 0;
 130                         break;
 131                 default:
 132                         col++;
 133                         break;
 134         }
 135 }