BSD 4_3_Net_2 release

[unix-history] / usr / src / usr.bin / unexpand / unexpand.c

/*-
* Copyright (c) 1980 The Regents of the University of California.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
*    notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
*    notice, this list of conditions and the following disclaimer in the
*    documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
*    must display the following acknowledgement:
*      This product includes software developed by the University of
*      California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
*    may be used to endorse or promote products derived from this software
*    without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/

#ifndef lint
char copyright[] =
"@(#) Copyright (c) 1980 The Regents of the University of California.\n\
All rights reserved.\n";
#endif /* not lint */

#ifndef lint
static char sccsid[] = "@(#)unexpand.c  5.3 (Berkeley) 4/18/91";
#endif /* not lint */

/*
* unexpand - put tabs into a file replacing blanks
*/
#include <stdio.h>

char    genbuf[BUFSIZ];
char    linebuf[BUFSIZ];
int     all;

main(argc, argv)
       int argc;
       char *argv[];
{
       register char *cp;

       argc--, argv++;
       if (argc > 0 && argv[0][0] == '-') {
               if (strcmp(argv[0], "-a") != 0) {
                       fprintf(stderr, "usage: unexpand [ -a ] file ...\n");
                       exit(1);
               }
               all++;
               argc--, argv++;
       }
       do {
               if (argc > 0) {
                       if (freopen(argv[0], "r", stdin) == NULL) {
                               perror(argv[0]);
                               exit(1);
                       }
                       argc--, argv++;
               }
               while (fgets(genbuf, BUFSIZ, stdin) != NULL) {
                       for (cp = linebuf; *cp; cp++)
                               continue;
                       if (cp > linebuf)
                               cp[-1] = 0;
                       tabify(all);
                       printf("%s", linebuf);
               }
       } while (argc > 0);
       exit(0);
}

tabify(c)
       char c;
{
       register char *cp, *dp;
       register int dcol;
       int ocol;

       ocol = 0;
       dcol = 0;
       cp = genbuf, dp = linebuf;
       for (;;) {
               switch (*cp) {

               case ' ':
                       dcol++;
                       break;

               case '\t':
                       dcol += 8;
                       dcol &= ~07;
                       break;

               default:
                       while (((ocol + 8) &~ 07) <= dcol) {
                               if (ocol + 1 == dcol)
                                       break;
                               *dp++ = '\t';
                               ocol += 8;
                               ocol &= ~07;
                       }
                       while (ocol < dcol) {
                               *dp++ = ' ';
                               ocol++;
                       }
                       if (*cp == 0 || c == 0) {
                               strcpy(dp, cp);
                               return;
                       }
                       *dp++ = *cp;
                       ocol++, dcol++;
               }
               cp++;
       }
}