unexpand.c revision 1591 
1/*-
2 * Copyright (c) 1980, 1993
3 *	The Regents of the University of California.  All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 * 3. All advertising materials mentioning features or use of this software
14 *    must display the following acknowledgement:
15 *	This product includes software developed by the University of
16 *	California, Berkeley and its contributors.
17 * 4. Neither the name of the University nor the names of its contributors
18 *    may be used to endorse or promote products derived from this software
19 *    without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 */
33
34#ifndef lint
35static char copyright[] =
36"@(#) Copyright (c) 1980, 1993\n\
37	The Regents of the University of California.  All rights reserved.\n";
38#endif /* not lint */
39
40#ifndef lint
41static char sccsid[] = "@(#)unexpand.c	8.1 (Berkeley) 6/6/93";
42#endif /* not lint */
43
44/*
45 * unexpand - put tabs into a file replacing blanks
46 */
47#include <stdio.h>
48
49char	genbuf[BUFSIZ];
50char	linebuf[BUFSIZ];
51int	all;
52
53main(argc, argv)
54	int argc;
55	char *argv[];
56{
57	register char *cp;
58
59	argc--, argv++;
60	if (argc > 0 && argv[0][0] == '-') {
61		if (strcmp(argv[0], "-a") != 0) {
62			fprintf(stderr, "usage: unexpand [ -a ] file ...\n");
63			exit(1);
64		}
65		all++;
66		argc--, argv++;
67	}
68	do {
69		if (argc > 0) {
70			if (freopen(argv[0], "r", stdin) == NULL) {
71				perror(argv[0]);
72				exit(1);
73			}
74			argc--, argv++;
75		}
76		while (fgets(genbuf, BUFSIZ, stdin) != NULL) {
77			for (cp = linebuf; *cp; cp++)
78				continue;
79			if (cp > linebuf)
80				cp[-1] = 0;
81			tabify(all);
82			printf("%s", linebuf);
83		}
84	} while (argc > 0);
85	exit(0);
86}
87
88tabify(c)
89	char c;
90{
91	register char *cp, *dp;
92	register int dcol;
93	int ocol;
94
95	ocol = 0;
96	dcol = 0;
97	cp = genbuf, dp = linebuf;
98	for (;;) {
99		switch (*cp) {
100
101		case ' ':
102			dcol++;
103			break;
104
105		case '\t':
106			dcol += 8;
107			dcol &= ~07;
108			break;
109
110		default:
111			while (((ocol + 8) &~ 07) <= dcol) {
112				if (ocol + 1 == dcol)
113					break;
114				*dp++ = '\t';
115				ocol += 8;
116				ocol &= ~07;
117			}
118			while (ocol < dcol) {
119				*dp++ = ' ';
120				ocol++;
121			}
122			if (*cp == 0 || c == 0) {
123				strcpy(dp, cp);
124				return;
125			}
126			*dp++ = *cp;
127			ocol++, dcol++;
128		}
129		cp++;
130	}
131}
132