xref: /freebsd/usr.bin/expand/expand.c (revision 2be1a816b9ff69588e55be0a84cbe2a31efc0f2f)
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("$FreeBSD$");
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 #include <wchar.h>
55 #include <wctype.h>
56 
57 /*
58  * expand - expand tabs to equivalent spaces
59  */
60 int	nstops;
61 int	tabstops[100];
62 
63 static void getstops(char *);
64 static void usage(void);
65 
66 int
67 main(int argc, char *argv[])
68 {
69 	const char *curfile;
70 	wint_t wc;
71 	int c, column;
72 	int n;
73 	int rval;
74 	int width;
75 
76 	setlocale(LC_CTYPE, "");
77 
78 	/* handle obsolete syntax */
79 	while (argc > 1 && argv[1][0] == '-' &&
80 	    isdigit((unsigned char)argv[1][1])) {
81 		getstops(&argv[1][1]);
82 		argc--; argv++;
83 	}
84 
85 	while ((c = getopt (argc, argv, "t:")) != -1) {
86 		switch (c) {
87 		case 't':
88 			getstops(optarg);
89 			break;
90 		case '?':
91 		default:
92 			usage();
93 			/* NOTREACHED */
94 		}
95 	}
96 	argc -= optind;
97 	argv += optind;
98 
99 	rval = 0;
100 	do {
101 		if (argc > 0) {
102 			if (freopen(argv[0], "r", stdin) == NULL) {
103 				warn("%s", argv[0]);
104 				rval = 1;
105 				argc--, argv++;
106 				continue;
107 			}
108 			curfile = argv[0];
109 			argc--, argv++;
110 		} else
111 			curfile = "stdin";
112 		column = 0;
113 		while ((wc = getwchar()) != WEOF) {
114 			switch (wc) {
115 			case '\t':
116 				if (nstops == 0) {
117 					do {
118 						putwchar(' ');
119 						column++;
120 					} while (column & 07);
121 					continue;
122 				}
123 				if (nstops == 1) {
124 					do {
125 						putwchar(' ');
126 						column++;
127 					} while (((column - 1) % tabstops[0]) != (tabstops[0] - 1));
128 					continue;
129 				}
130 				for (n = 0; n < nstops; n++)
131 					if (tabstops[n] > column)
132 						break;
133 				if (n == nstops) {
134 					putwchar(' ');
135 					column++;
136 					continue;
137 				}
138 				while (column < tabstops[n]) {
139 					putwchar(' ');
140 					column++;
141 				}
142 				continue;
143 
144 			case '\b':
145 				if (column)
146 					column--;
147 				putwchar('\b');
148 				continue;
149 
150 			default:
151 				putwchar(wc);
152 				if ((width = wcwidth(wc)) > 0)
153 					column += width;
154 				continue;
155 
156 			case '\n':
157 				putwchar(wc);
158 				column = 0;
159 				continue;
160 			}
161 		}
162 		if (ferror(stdin)) {
163 			warn("%s", curfile);
164 			rval = 1;
165 		}
166 	} while (argc > 0);
167 	exit(rval);
168 }
169 
170 static void
171 getstops(char *cp)
172 {
173 	int i;
174 
175 	nstops = 0;
176 	for (;;) {
177 		i = 0;
178 		while (*cp >= '0' && *cp <= '9')
179 			i = i * 10 + *cp++ - '0';
180 		if (i <= 0)
181 			errx(1, "bad tab stop spec");
182 		if (nstops > 0 && i <= tabstops[nstops-1])
183 			errx(1, "bad tab stop spec");
184 		if (nstops == sizeof(tabstops) / sizeof(*tabstops))
185 			errx(1, "too many tab stops");
186 		tabstops[nstops++] = i;
187 		if (*cp == 0)
188 			break;
189 		if (*cp != ',' && !isblank((unsigned char)*cp))
190 			errx(1, "bad tab stop spec");
191 		cp++;
192 	}
193 }
194 
195 static void
196 usage(void)
197 {
198 	(void)fprintf (stderr, "usage: expand [-t tablist] [file ...]\n");
199 	exit(1);
200 }
201