expand.c revision 331722 
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 * 4. Neither the name of the University nor the names of its contributors
14 *    may be used to endorse or promote products derived from this software
15 *    without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 */
29
30#ifndef lint
31static const char copyright[] =
32"@(#) Copyright (c) 1980, 1993\n\
33	The Regents of the University of California.  All rights reserved.\n";
34#endif /* not lint */
35
36#ifndef lint
37#if 0
38static char sccsid[] = "@(#)expand.c	8.1 (Berkeley) 6/9/93";
39#endif
40#endif /* not lint */
41#include <sys/cdefs.h>
42__FBSDID("$FreeBSD: stable/11/usr.bin/expand/expand.c 331722 2018-03-29 02:50:57Z eadler $");
43
44#include <ctype.h>
45#include <err.h>
46#include <locale.h>
47#include <stdio.h>
48#include <stdlib.h>
49#include <unistd.h>
50#include <wchar.h>
51#include <wctype.h>
52
53/*
54 * expand - expand tabs to equivalent spaces
55 */
56static int	nstops;
57static int	tabstops[100];
58
59static void getstops(char *);
60static void usage(void);
61
62int
63main(int argc, char *argv[])
64{
65	const char *curfile;
66	wint_t wc;
67	int c, column;
68	int n;
69	int rval;
70	int width;
71
72	setlocale(LC_CTYPE, "");
73
74	/* handle obsolete syntax */
75	while (argc > 1 && argv[1][0] == '-' &&
76	    isdigit((unsigned char)argv[1][1])) {
77		getstops(&argv[1][1]);
78		argc--; argv++;
79	}
80
81	while ((c = getopt (argc, argv, "t:")) != -1) {
82		switch (c) {
83		case 't':
84			getstops(optarg);
85			break;
86		case '?':
87		default:
88			usage();
89			/* NOTREACHED */
90		}
91	}
92	argc -= optind;
93	argv += optind;
94
95	rval = 0;
96	do {
97		if (argc > 0) {
98			if (freopen(argv[0], "r", stdin) == NULL) {
99				warn("%s", argv[0]);
100				rval = 1;
101				argc--, argv++;
102				continue;
103			}
104			curfile = argv[0];
105			argc--, argv++;
106		} else
107			curfile = "stdin";
108		column = 0;
109		while ((wc = getwchar()) != WEOF) {
110			switch (wc) {
111			case '\t':
112				if (nstops == 0) {
113					do {
114						putwchar(' ');
115						column++;
116					} while (column & 07);
117					continue;
118				}
119				if (nstops == 1) {
120					do {
121						putwchar(' ');
122						column++;
123					} while (((column - 1) % tabstops[0]) != (tabstops[0] - 1));
124					continue;
125				}
126				for (n = 0; n < nstops; n++)
127					if (tabstops[n] > column)
128						break;
129				if (n == nstops) {
130					putwchar(' ');
131					column++;
132					continue;
133				}
134				while (column < tabstops[n]) {
135					putwchar(' ');
136					column++;
137				}
138				continue;
139
140			case '\b':
141				if (column)
142					column--;
143				putwchar('\b');
144				continue;
145
146			default:
147				putwchar(wc);
148				if ((width = wcwidth(wc)) > 0)
149					column += width;
150				continue;
151
152			case '\n':
153				putwchar(wc);
154				column = 0;
155				continue;
156			}
157		}
158		if (ferror(stdin)) {
159			warn("%s", curfile);
160			rval = 1;
161		}
162	} while (argc > 0);
163	exit(rval);
164}
165
166static void
167getstops(char *cp)
168{
169	int i;
170
171	nstops = 0;
172	for (;;) {
173		i = 0;
174		while (*cp >= '0' && *cp <= '9')
175			i = i * 10 + *cp++ - '0';
176		if (i <= 0)
177			errx(1, "bad tab stop spec");
178		if (nstops > 0 && i <= tabstops[nstops-1])
179			errx(1, "bad tab stop spec");
180		if (nstops == sizeof(tabstops) / sizeof(*tabstops))
181			errx(1, "too many tab stops");
182		tabstops[nstops++] = i;
183		if (*cp == 0)
184			break;
185		if (*cp != ',' && !isblank((unsigned char)*cp))
186			errx(1, "bad tab stop spec");
187		cp++;
188	}
189}
190
191static void
192usage(void)
193{
194	(void)fprintf (stderr, "usage: expand [-t tablist] [file ...]\n");
195	exit(1);
196}
197