xref: /dragonfly/usr.bin/expand/expand.c (revision 984263bc)
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
35 static 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
42 static char sccsid[] = "@(#)expand.c	8.1 (Berkeley) 6/9/93";
43 #endif
44 #endif /* not lint */
45 #include <sys/cdefs.h>
46 __FBSDID("$FreeBSD: src/usr.bin/expand/expand.c,v 1.5.2.6 2002/07/09 10:47:59 tjr Exp $");
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  */
58 int	nstops;
59 int	tabstops[100];
60 
61 static void getstops(char *);
62 static void usage(void);
63 
64 int
65 main(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 
161 static void
162 getstops(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 
187 static void
188 usage()
189 {
190 	(void)fprintf (stderr, "usage: expand [-t tablist] [file ...]\n");
191 	exit(1);
192 }
193