expand.c revision 98251 
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 const 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
41#if 0
42static char sccsid[] = "@(#)expand.c	8.1 (Berkeley) 6/9/93";
43#endif
44static const char rcsid[] =
45  "$FreeBSD: head/usr.bin/expand/expand.c 98251 2002-06-15 10:16:39Z tjr $";
46#endif /* not lint */
47
48#include <ctype.h>
49#include <err.h>
50#include <locale.h>
51#include <stdio.h>
52#include <stdlib.h>
53#include <unistd.h>
54
55/*
56 * expand - expand tabs to equivalent spaces
57 */
58int	nstops;
59int	tabstops[100];
60
61static void getstops(char *);
62static void usage(void);
63
64int
65main(argc, argv)
66	int argc;
67	char *argv[];
68{
69	register int c, column;
70	register int n;
71	int rval;
72
73	setlocale(LC_CTYPE, "");
74
75	/* handle obsolete syntax */
76	while (argc > 1 && argv[1][0] == '-' &&
77	    isdigit((unsigned char)argv[1][1])) {
78		getstops(&argv[1][1]);
79		argc--; argv++;
80	}
81
82	while ((c = getopt (argc, argv, "t:")) != -1) {
83		switch (c) {
84		case 't':
85			getstops(optarg);
86			break;
87		case '?':
88		default:
89			usage();
90			/* NOTREACHED */
91		}
92	}
93	argc -= optind;
94	argv += optind;
95
96	rval = 0;
97	do {
98		if (argc > 0) {
99			if (freopen(argv[0], "r", stdin) == NULL) {
100				warn("%s", argv[0]);
101				rval = 1;
102				argc--, argv++;
103				continue;
104			}
105			argc--, argv++;
106		}
107		column = 0;
108		while ((c = getchar()) != EOF) {
109			switch (c) {
110			case '\t':
111				if (nstops == 0) {
112					do {
113						putchar(' ');
114						column++;
115					} while (column & 07);
116					continue;
117				}
118				if (nstops == 1) {
119					do {
120						putchar(' ');
121						column++;
122					} while (((column - 1) % tabstops[0]) != (tabstops[0] - 1));
123					continue;
124				}
125				for (n = 0; n < nstops; n++)
126					if (tabstops[n] > column)
127						break;
128				if (n == nstops) {
129					putchar(' ');
130					column++;
131					continue;
132				}
133				while (column < tabstops[n]) {
134					putchar(' ');
135					column++;
136				}
137				continue;
138
139			case '\b':
140				if (column)
141					column--;
142				putchar('\b');
143				continue;
144
145			default:
146				putchar(c);
147				if (isprint(c))
148					column++;
149				continue;
150
151			case '\n':
152				putchar(c);
153				column = 0;
154				continue;
155			}
156		}
157	} while (argc > 0);
158	exit(rval);
159}
160
161static void
162getstops(cp)
163	register char *cp;
164{
165	register int i;
166
167	nstops = 0;
168	for (;;) {
169		i = 0;
170		while (*cp >= '0' && *cp <= '9')
171			i = i * 10 + *cp++ - '0';
172		if (i <= 0)
173			errx(1, "bad tab stop spec");
174		if (nstops > 0 && i <= tabstops[nstops-1])
175			errx(1, "bad tab stop spec");
176		if (nstops == sizeof(tabstops) / sizeof(*tabstops))
177			errx(1, "too many tab stops");
178		tabstops[nstops++] = i;
179		if (*cp == 0)
180			break;
181		if (*cp != ',' && !isblank((unsigned char)*cp))
182			errx(1, "bad tab stop spec");
183		cp++;
184	}
185}
186
187static void
188usage()
189{
190	(void)fprintf (stderr, "usage: expand [-t tablist] [file ...]\n");
191	exit(1);
192}
193