1 /* $NetBSD: unexpand.c,v 1.14 2008/12/21 02:33:13 christos 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. Neither the name of the University nor the names of its contributors
16 * may be used to endorse or promote products derived from this software
17 * without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 */
31
32 #include <sys/cdefs.h>
33 #ifndef lint
34 __COPYRIGHT("@(#) Copyright (c) 1980, 1993\
35 The Regents of the University of California. All rights reserved.");
36 #endif /* not lint */
37
38 #ifndef lint
39 #if 0
40 static char sccsid[] = "@(#)unexpand.c 8.1 (Berkeley) 6/6/93";
41 #endif
42 __RCSID("$NetBSD: unexpand.c,v 1.14 2008/12/21 02:33:13 christos Exp $");
43 #endif /* not lint */
44
45 /*
46 * unexpand - put tabs into a file replacing blanks
47 */
48 #include <limits.h>
49 #include <stdio.h>
50 #include <stdlib.h>
51 #include <string.h>
52 #include <unistd.h>
53 #include <errno.h>
54 #include <err.h>
55 #include <util.h>
56
57
58 #define DSTOP 8
59 static int all;
60 static size_t nstops;
61 static size_t maxstops;
62 static size_t *tabstops;
63
64 static void tabify(const char *, size_t);
65 static void usage(void) __attribute__((__noreturn__));
66
67 static void
usage(void)68 usage(void)
69 {
70 (void)fprintf(stderr, "Usage: %s [-a] [-t tabstop] [file ...]\n",
71 getprogname());
72 exit(EXIT_FAILURE);
73 }
74
75 int
main(int argc,char ** argv)76 main(int argc, char **argv)
77 {
78 int c;
79 char *ep, *tab;
80 char *line;
81 size_t len;
82 unsigned long i;
83
84 setprogname(argv[0]);
85
86 while ((c = getopt(argc, argv, "at:")) != -1) {
87 switch (c) {
88 case 'a':
89 if (nstops)
90 usage();
91 all++;
92 break;
93 case 't':
94 if (all)
95 usage();
96 while ((tab = strsep(&optarg, ", \t")) != NULL) {
97 if (*tab == '\0')
98 continue;
99 errno = 0;
100 i = strtoul(tab, &ep, 0);
101 if (*ep || (errno == ERANGE && i == ULONG_MAX))
102 errx(EXIT_FAILURE,
103 "Invalid tabstop `%s'", tab);
104 if (nstops >= maxstops) {
105 maxstops += 20;
106 tabstops = erealloc(tabstops, maxstops);
107 }
108 if (nstops && tabstops[nstops - 1] >= (size_t)i)
109 errx(EXIT_FAILURE,
110 "Bad tabstop spec `%s', must be "
111 "greater than the previous `%zu'",
112 tab, tabstops[nstops - 1]);
113 tabstops[nstops++] = i;
114 }
115 break;
116 case '?':
117 default:
118 usage();
119 }
120 }
121 argc -= optind;
122 argv += optind;
123
124 for (i = 0; i < nstops; i++)
125 fprintf(stderr, "%lu %zu\n", i, tabstops[i]);
126
127 do {
128 if (argc > 0) {
129 if (freopen(argv[0], "r", stdin) == NULL)
130 err(EXIT_FAILURE, "Cannot open `%s'", argv[0]);
131 argc--, argv++;
132 }
133 while ((line = fgetln(stdin, &len)) != NULL)
134 tabify(line, len);
135 } while (argc > 0);
136 return EXIT_SUCCESS;
137 }
138
139 static void
tabify(const char * line,size_t len)140 tabify(const char *line, size_t len)
141 {
142 const char *e, *p;
143 size_t dcol, ocol, limit, n;
144
145 dcol = ocol = 0;
146 limit = nstops == 0 ? UINT_MAX : tabstops[nstops - 1] - 1;
147 e = line + len;
148 for (p = line; p < e; p++) {
149 if (*p == ' ') {
150 dcol++;
151 continue;
152 } else if (*p == '\t') {
153 if (nstops == 0) {
154 dcol = (1 + dcol / DSTOP) * DSTOP;
155 continue;
156 } else {
157 for (n = 0; tabstops[n] - 1 < dcol &&
158 n < nstops; n++)
159 continue;
160 if (n < nstops - 1 && tabstops[n] - 1 < limit) {
161 dcol = tabstops[n];
162 continue;
163 }
164 }
165 }
166
167 /* Output our tabs */
168 if (nstops == 0) {
169 while (((ocol + DSTOP) / DSTOP) <= (dcol / DSTOP)) {
170 if (dcol - ocol < 2)
171 break;
172 if (putchar('\t') == EOF)
173 goto out;
174 ocol = (1 + ocol / DSTOP) * DSTOP;
175 }
176 } else {
177 for (n = 0; tabstops[n] <= ocol && n < nstops; n++)
178 continue;
179 while (tabstops[n] <= dcol && ocol < dcol &&
180 n < nstops && ocol < limit) {
181 if (putchar('\t') == EOF)
182 goto out;
183 ocol = tabstops[n++];
184 }
185 }
186
187 /* Output remaining spaces */
188 while (ocol < dcol && ocol < limit) {
189 if (putchar(' ') == EOF)
190 goto out;
191 ocol++;
192 }
193
194 /* Output our char */
195 if (putchar(*p) == EOF)
196 goto out;
197 if (*p == '\b') {
198 if (ocol > 0) {
199 ocol--;
200 dcol--;
201 }
202 } else {
203 ocol++;
204 dcol++;
205 }
206
207 /* Output remainder of line */
208 if (!all || dcol >= limit) {
209 for (p++; p < e; p++)
210 if (putchar(*p) == EOF)
211 goto out;
212 return;
213 }
214 }
215 return;
216 out:
217 err(EXIT_FAILURE, "write failed");
218 }
219