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#include <sys/cdefs.h>
35
36__FBSDID("$FreeBSD: src/usr.bin/unexpand/unexpand.c,v 1.15 2006/10/13 16:22:25 ru Exp $");
37
38#ifndef lint
39static const char copyright[] =
40"@(#) Copyright (c) 1980, 1993\n\
41	The Regents of the University of California.  All rights reserved.\n";
42#endif
43
44#ifndef lint
45static const char sccsid[] = "@(#)unexpand.c	8.1 (Berkeley) 6/6/93";
46#endif
47
48/*
49 * unexpand - put tabs into a file replacing blanks
50 */
51#include <ctype.h>
52#include <err.h>
53#include <limits.h>
54#include <locale.h>
55#include <stdio.h>
56#include <stdlib.h>
57#include <string.h>
58#include <unistd.h>
59#include <wchar.h>
60#include <wctype.h>
61
62int	all;
63int	nstops;
64int	tabstops[100];
65
66static void getstops(const char *);
67static void usage(void);
68static int tabify(const char *);
69
70int
71main(int argc, char *argv[])
72{
73	int ch, failed;
74	char *filename;
75
76	setlocale(LC_CTYPE, "");
77
78	nstops = 1;
79	tabstops[0] = 8;
80	while ((ch = getopt(argc, argv, "at:")) != -1) {
81		switch (ch) {
82		case 'a':	/* Un-expand all spaces, not just leading. */
83			all = 1;
84			break;
85		case 't':	/* Specify tab list, implies -a. */
86			getstops(optarg);
87			all = 1;
88			break;
89		default:
90			usage();
91			/*NOTREACHED*/
92		}
93	}
94	argc -= optind;
95	argv += optind;
96
97	failed = 0;
98	if (argc == 0)
99		failed |= tabify("stdin");
100	else {
101		while ((filename = *argv++) != NULL) {
102			if (freopen(filename, "r", stdin) == NULL) {
103				warn("%s", filename);
104				failed = 1;
105			} else
106				failed |= tabify(filename);
107		}
108	}
109	exit(failed != 0);
110}
111
112static void
113usage(void)
114{
115	fprintf(stderr, "usage: unexpand [-a | -t tablist] [file ...]\n");
116	exit(1);
117}
118
119static int
120tabify(const char *curfile)
121{
122	int dcol, doneline, limit, n, ocol, width;
123	wint_t ch;
124
125	limit = nstops == 1 ? INT_MAX : tabstops[nstops - 1] - 1;
126
127	doneline = ocol = dcol = 0;
128	while ((ch = getwchar()) != WEOF) {
129		if (ch == ' ' && !doneline) {
130			if (++dcol >= limit)
131				doneline = 1;
132			continue;
133		} else if (ch == '\t') {
134			if (nstops == 1) {
135				dcol = (1 + dcol / tabstops[0]) *
136				    tabstops[0];
137				continue;
138			} else {
139				for (n = 0; tabstops[n] - 1 < dcol &&
140				    n < nstops; n++)
141					;
142				if (n < nstops - 1 && tabstops[n] - 1 < limit) {
143					dcol = tabstops[n];
144					continue;
145				}
146				doneline = 1;
147			}
148		}
149
150		/* Output maximal number of tabs. */
151		if (nstops == 1) {
152			while (((ocol + tabstops[0]) / tabstops[0])
153			    <= (dcol / tabstops[0])) {
154				if (dcol - ocol < 2)
155					break;
156				putwchar('\t');
157				ocol = (1 + ocol / tabstops[0]) *
158				    tabstops[0];
159			}
160		} else {
161			for (n = 0; tabstops[n] - 1 < ocol && n < nstops; n++)
162				;
163			while (ocol < dcol && n < nstops && ocol < limit) {
164				putwchar('\t');
165				ocol = tabstops[n++];
166			}
167		}
168
169		/* Then spaces. */
170		while (ocol < dcol && ocol < limit) {
171			putwchar(' ');
172			ocol++;
173		}
174
175		if (ch == '\b') {
176			putwchar('\b');
177			if (ocol > 0)
178				ocol--, dcol--;
179		} else if (ch == '\n') {
180			putwchar('\n');
181			doneline = ocol = dcol = 0;
182			continue;
183		} else if (ch != ' ' || dcol > limit) {
184			putwchar(ch);
185			if ((width = wcwidth(ch)) > 0)
186				ocol += width, dcol += width;
187		}
188
189		/*
190		 * Only processing leading blanks or we've gone past the
191		 * last tab stop. Emit remainder of this line unchanged.
192		 */
193		if (!all || dcol >= limit) {
194			while ((ch = getwchar()) != '\n' && ch != WEOF)
195				putwchar(ch);
196			if (ch == '\n')
197				putwchar('\n');
198			doneline = ocol = dcol = 0;
199		}
200	}
201	if (ferror(stdin)) {
202		warn("%s", curfile);
203		return (1);
204	}
205	return (0);
206}
207
208static void
209getstops(const char *cp)
210{
211	int i;
212
213	nstops = 0;
214	for (;;) {
215		i = 0;
216		while (*cp >= '0' && *cp <= '9')
217			i = i * 10 + *cp++ - '0';
218		if (i <= 0)
219			errx(1, "bad tab stop spec");
220		if (nstops > 0 && i <= tabstops[nstops-1])
221			errx(1, "bad tab stop spec");
222		if (nstops == sizeof(tabstops) / sizeof(*tabstops))
223			errx(1, "too many tab stops");
224		tabstops[nstops++] = i;
225		if (*cp == 0)
226			break;
227		if (*cp != ',' && !isblank((unsigned char)*cp))
228			errx(1, "bad tab stop spec");
229		cp++;
230	}
231}
232