1 /*-
2 * SPDX-License-Identifier: BSD-3-Clause
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 /*
33 * unexpand - put tabs into a file replacing blanks
34 */
35 #include <ctype.h>
36 #include <err.h>
37 #include <limits.h>
38 #include <locale.h>
39 #include <stdio.h>
40 #include <stdlib.h>
41 #include <string.h>
42 #include <unistd.h>
43 #include <wchar.h>
44 #include <wctype.h>
45
46 static int all;
47 static int nstops;
48 static int tabstops[100];
49
50 static void getstops(const char *);
51 static void usage(void) __dead2;
52 static int tabify(const char *);
53
54 int
main(int argc,char * argv[])55 main(int argc, char *argv[])
56 {
57 int ch, failed;
58 char *filename;
59
60 setlocale(LC_CTYPE, "");
61
62 nstops = 1;
63 tabstops[0] = 8;
64 while ((ch = getopt(argc, argv, "at:")) != -1) {
65 switch (ch) {
66 case 'a': /* Un-expand all spaces, not just leading. */
67 all = 1;
68 break;
69 case 't': /* Specify tab list, implies -a. */
70 getstops(optarg);
71 all = 1;
72 break;
73 default:
74 usage();
75 /*NOTREACHED*/
76 }
77 }
78 argc -= optind;
79 argv += optind;
80
81 failed = 0;
82 if (argc == 0)
83 failed |= tabify("stdin");
84 else {
85 while ((filename = *argv++) != NULL) {
86 if (freopen(filename, "r", stdin) == NULL) {
87 warn("%s", filename);
88 failed = 1;
89 } else
90 failed |= tabify(filename);
91 }
92 }
93 exit(failed != 0);
94 }
95
96 static void
usage(void)97 usage(void)
98 {
99 fprintf(stderr, "usage: unexpand [-a | -t tablist] [file ...]\n");
100 exit(1);
101 }
102
103 static int
tabify(const char * curfile)104 tabify(const char *curfile)
105 {
106 int dcol, doneline, limit, n, ocol, width;
107 wint_t ch;
108
109 limit = nstops == 1 ? INT_MAX : tabstops[nstops - 1] - 1;
110
111 doneline = ocol = dcol = 0;
112 while ((ch = getwchar()) != WEOF) {
113 if (ch == ' ' && !doneline) {
114 if (++dcol >= limit)
115 doneline = 1;
116 continue;
117 } else if (ch == '\t') {
118 if (nstops == 1) {
119 dcol = (1 + dcol / tabstops[0]) *
120 tabstops[0];
121 continue;
122 } else {
123 for (n = 0; n < nstops &&
124 tabstops[n] - 1 < dcol; n++)
125 ;
126 if (n < nstops - 1 && tabstops[n] - 1 < limit) {
127 dcol = tabstops[n];
128 continue;
129 }
130 doneline = 1;
131 }
132 }
133
134 /* Output maximal number of tabs. */
135 if (nstops == 1) {
136 while (((ocol + tabstops[0]) / tabstops[0])
137 <= (dcol / tabstops[0])) {
138 if (dcol - ocol < 2)
139 break;
140 putwchar('\t');
141 ocol = (1 + ocol / tabstops[0]) *
142 tabstops[0];
143 }
144 } else {
145 for (n = 0; n < nstops && tabstops[n] - 1 < ocol; n++)
146 ;
147 while (ocol < dcol && n < nstops && ocol < limit) {
148 putwchar('\t');
149 ocol = tabstops[n++];
150 }
151 }
152
153 /* Then spaces. */
154 while (ocol < dcol && ocol < limit) {
155 putwchar(' ');
156 ocol++;
157 }
158
159 if (ch == '\b') {
160 putwchar('\b');
161 if (ocol > 0)
162 ocol--, dcol--;
163 } else if (ch == '\n') {
164 putwchar('\n');
165 doneline = ocol = dcol = 0;
166 continue;
167 } else if (ch != ' ' || dcol > limit) {
168 putwchar(ch);
169 if ((width = wcwidth(ch)) > 0)
170 ocol += width, dcol += width;
171 }
172
173 /*
174 * Only processing leading blanks or we've gone past the
175 * last tab stop. Emit remainder of this line unchanged.
176 */
177 if (!all || dcol >= limit) {
178 while ((ch = getwchar()) != '\n' && ch != WEOF)
179 putwchar(ch);
180 if (ch == '\n')
181 putwchar('\n');
182 doneline = ocol = dcol = 0;
183 }
184 }
185 if (ferror(stdin)) {
186 warn("%s", curfile);
187 return (1);
188 }
189 return (0);
190 }
191
192 static void
getstops(const char * cp)193 getstops(const char *cp)
194 {
195 int i;
196
197 nstops = 0;
198 for (;;) {
199 i = 0;
200 while (*cp >= '0' && *cp <= '9')
201 i = i * 10 + *cp++ - '0';
202 if (i <= 0)
203 errx(1, "bad tab stop spec");
204 if (nstops > 0 && i <= tabstops[nstops-1])
205 errx(1, "bad tab stop spec");
206 if (nstops == sizeof(tabstops) / sizeof(*tabstops))
207 errx(1, "too many tab stops");
208 tabstops[nstops++] = i;
209 if (*cp == 0)
210 break;
211 if (*cp != ',' && !isblank((unsigned char)*cp))
212 errx(1, "bad tab stop spec");
213 cp++;
214 }
215 }
216