xref: /netbsd-src/usr.bin/unexpand/unexpand.c (revision ae9172d6cd9432a6a1a56760d86b32c57a66c39c)
1 /*	$NetBSD: unexpand.c,v 1.4 1994/12/20 01:30:26 jtc Exp $	*/
2 
3 /*-
4  * Copyright (c) 1980, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. All advertising materials mentioning features or use of this software
16  *    must display the following acknowledgement:
17  *	This product includes software developed by the University of
18  *	California, Berkeley and its contributors.
19  * 4. Neither the name of the University nor the names of its contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  */
35 
36 #ifndef lint
37 static char copyright[] =
38 "@(#) Copyright (c) 1980, 1993\n\
39 	The Regents of the University of California.  All rights reserved.\n";
40 #endif /* not lint */
41 
42 #ifndef lint
43 #if 0
44 static char sccsid[] = "@(#)unexpand.c	8.1 (Berkeley) 6/6/93";
45 #endif
46 static char rcsid[] = "$NetBSD: unexpand.c,v 1.4 1994/12/20 01:30:26 jtc Exp $";
47 #endif /* not lint */
48 
49 /*
50  * unexpand - put tabs into a file replacing blanks
51  */
52 #include <stdio.h>
53 
54 char	genbuf[BUFSIZ];
55 char	linebuf[BUFSIZ];
56 int	all;
57 
58 void tabify __P((char));
59 
60 int
61 main(argc, argv)
62 	int argc;
63 	char *argv[];
64 {
65 	register char *cp;
66 
67 	argc--, argv++;
68 	if (argc > 0 && argv[0][0] == '-') {
69 		if (strcmp(argv[0], "-a") != 0) {
70 			fprintf(stderr, "usage: unexpand [ -a ] file ...\n");
71 			exit(1);
72 		}
73 		all++;
74 		argc--, argv++;
75 	}
76 	do {
77 		if (argc > 0) {
78 			if (freopen(argv[0], "r", stdin) == NULL) {
79 				perror(argv[0]);
80 				exit(1);
81 			}
82 			argc--, argv++;
83 		}
84 		while (fgets(genbuf, BUFSIZ, stdin) != NULL) {
85 			for (cp = linebuf; *cp; cp++)
86 				continue;
87 			if (cp > linebuf)
88 				cp[-1] = 0;
89 			tabify(all);
90 			printf("%s", linebuf);
91 		}
92 	} while (argc > 0);
93 	exit(0);
94 }
95 
96 void
97 tabify(c)
98 	char c;
99 {
100 	register char *cp, *dp;
101 	register int dcol;
102 	int ocol;
103 
104 	ocol = 0;
105 	dcol = 0;
106 	cp = genbuf, dp = linebuf;
107 	for (;;) {
108 		switch (*cp) {
109 
110 		case ' ':
111 			dcol++;
112 			break;
113 
114 		case '\t':
115 			dcol += 8;
116 			dcol &= ~07;
117 			break;
118 
119 		default:
120 			while (((ocol + 8) &~ 07) <= dcol) {
121 				if (ocol + 1 == dcol)
122 					break;
123 				*dp++ = '\t';
124 				ocol += 8;
125 				ocol &= ~07;
126 			}
127 			while (ocol < dcol) {
128 				*dp++ = ' ';
129 				ocol++;
130 			}
131 			if (*cp == 0 || c == 0) {
132 				strcpy(dp, cp);
133 				return;
134 			}
135 			*dp++ = *cp;
136 			ocol++, dcol++;
137 		}
138 		cp++;
139 	}
140 }
141