xref: /freebsd/usr.bin/tr/tr.c (revision 257e70f1d5ee61037c8c59b116538d3b6b1427a2)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1988, 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/types.h>
33 #include <sys/capsicum.h>
34 
35 #include <capsicum_helpers.h>
36 #include <ctype.h>
37 #include <err.h>
38 #include <limits.h>
39 #include <locale.h>
40 #include <stdint.h>
41 #include <stdio.h>
42 #include <stdlib.h>
43 #include <string.h>
44 #include <unistd.h>
45 #include <wchar.h>
46 #include <wctype.h>
47 
48 #include "cmap.h"
49 #include "cset.h"
50 #include "extern.h"
51 
52 static STR s1 = { STRING1, NORMAL, 0, OOBCH, 0, { 0, OOBCH }, NULL, NULL };
53 static STR s2 = { STRING2, NORMAL, 0, OOBCH, 0, { 0, OOBCH }, NULL, NULL };
54 
55 static struct cset *setup(char *, STR *, int, int);
56 static void usage(void) __dead2;
57 
58 int
59 main(int argc, char **argv)
60 {
61 	static int carray[NCHARS_SB];
62 	struct cmap *map;
63 	struct cset *delete, *squeeze;
64 	int n, *p;
65 	int Cflag, cflag, dflag, sflag, isstring2;
66 	wint_t ch, cnt, lastch;
67 
68 	(void)setlocale(LC_ALL, "");
69 
70 	if (caph_limit_stdio() == -1)
71 		err(1, "unable to limit stdio");
72 
73 	if (caph_enter() < 0)
74 		err(1, "unable to enter capability mode");
75 
76 	Cflag = cflag = dflag = sflag = 0;
77 	while ((ch = getopt(argc, argv, "Ccdsu")) != -1)
78 		switch((char)ch) {
79 		case 'C':
80 			Cflag = 1;
81 			cflag = 0;
82 			break;
83 		case 'c':
84 			cflag = 1;
85 			Cflag = 0;
86 			break;
87 		case 'd':
88 			dflag = 1;
89 			break;
90 		case 's':
91 			sflag = 1;
92 			break;
93 		case 'u':
94 			setbuf(stdout, (char *)NULL);
95 			break;
96 		case '?':
97 		default:
98 			usage();
99 		}
100 	argc -= optind;
101 	argv += optind;
102 
103 	switch(argc) {
104 	case 0:
105 	default:
106 		usage();
107 		/* NOTREACHED */
108 	case 1:
109 		isstring2 = 0;
110 		break;
111 	case 2:
112 		isstring2 = 1;
113 		break;
114 	}
115 
116 	/*
117 	 * tr -ds [-Cc] string1 string2
118 	 * Delete all characters (or complemented characters) in string1.
119 	 * Squeeze all characters in string2.
120 	 */
121 	if (dflag && sflag) {
122 		if (!isstring2)
123 			usage();
124 
125 		delete = setup(argv[0], &s1, cflag, Cflag);
126 		squeeze = setup(argv[1], &s2, 0, 0);
127 
128 		for (lastch = OOBCH; (ch = getwchar()) != WEOF;)
129 			if (!cset_in(delete, ch) &&
130 			    (lastch != ch || !cset_in(squeeze, ch))) {
131 				lastch = ch;
132 				(void)putwchar(ch);
133 			}
134 		if (ferror(stdin))
135 			err(1, NULL);
136 		exit(0);
137 	}
138 
139 	/*
140 	 * tr -d [-Cc] string1
141 	 * Delete all characters (or complemented characters) in string1.
142 	 */
143 	if (dflag) {
144 		if (isstring2)
145 			usage();
146 
147 		delete = setup(argv[0], &s1, cflag, Cflag);
148 
149 		while ((ch = getwchar()) != WEOF)
150 			if (!cset_in(delete, ch))
151 				(void)putwchar(ch);
152 		if (ferror(stdin))
153 			err(1, NULL);
154 		exit(0);
155 	}
156 
157 	/*
158 	 * tr -s [-Cc] string1
159 	 * Squeeze all characters (or complemented characters) in string1.
160 	 */
161 	if (sflag && !isstring2) {
162 		squeeze = setup(argv[0], &s1, cflag, Cflag);
163 
164 		for (lastch = OOBCH; (ch = getwchar()) != WEOF;)
165 			if (lastch != ch || !cset_in(squeeze, ch)) {
166 				lastch = ch;
167 				(void)putwchar(ch);
168 			}
169 		if (ferror(stdin))
170 			err(1, NULL);
171 		exit(0);
172 	}
173 
174 	/*
175 	 * tr [-Ccs] string1 string2
176 	 * Replace all characters (or complemented characters) in string1 with
177 	 * the character in the same position in string2.  If the -s option is
178 	 * specified, squeeze all the characters in string2.
179 	 */
180 	if (!isstring2)
181 		usage();
182 
183 	map = cmap_alloc();
184 	if (map == NULL)
185 		err(1, NULL);
186 	squeeze = cset_alloc();
187 	if (squeeze == NULL)
188 		err(1, NULL);
189 
190 	s1.str = argv[0];
191 
192 	if (Cflag || cflag) {
193 		cmap_default(map, OOBCH);
194 		if ((s2.str = strdup(argv[1])) == NULL)
195 			errx(1, "strdup(argv[1])");
196 	} else
197 		s2.str = argv[1];
198 
199 	if (!next(&s2))
200 		errx(1, "empty string2");
201 
202 	/*
203 	 * For -s result will contain only those characters defined
204 	 * as the second characters in each of the toupper or tolower
205 	 * pairs.
206 	 */
207 
208 	/* If string2 runs out of characters, use the last one specified. */
209 	while (next(&s1)) {
210 	again:
211 		if (s1.state == CCLASS_LOWER &&
212 		    s2.state == CCLASS_UPPER &&
213 		    s1.cnt == 1 && s2.cnt == 1) {
214 			do {
215 				ch = towupper(s1.lastch);
216 				cmap_add(map, s1.lastch, ch);
217 				if (sflag && iswupper(ch))
218 					cset_add(squeeze, ch);
219 				if (!next(&s1))
220 					goto endloop;
221 			} while (s1.state == CCLASS_LOWER && s1.cnt > 1);
222 			/* skip upper set */
223 			do {
224 				if (!next(&s2))
225 					break;
226 			} while (s2.state == CCLASS_UPPER && s2.cnt > 1);
227 			goto again;
228 		} else if (s1.state == CCLASS_UPPER &&
229 			   s2.state == CCLASS_LOWER &&
230 			   s1.cnt == 1 && s2.cnt == 1) {
231 			do {
232 				ch = towlower(s1.lastch);
233 				cmap_add(map, s1.lastch, ch);
234 				if (sflag && iswlower(ch))
235 					cset_add(squeeze, ch);
236 				if (!next(&s1))
237 					goto endloop;
238 			} while (s1.state == CCLASS_UPPER && s1.cnt > 1);
239 			/* skip lower set */
240 			do {
241 				if (!next(&s2))
242 					break;
243 			} while (s2.state == CCLASS_LOWER && s2.cnt > 1);
244 			goto again;
245 		} else {
246 			cmap_add(map, s1.lastch, s2.lastch);
247 			if (sflag)
248 				cset_add(squeeze, s2.lastch);
249 		}
250 		(void)next(&s2);
251 	}
252 endloop:
253 	if (cflag || (Cflag && MB_CUR_MAX > 1)) {
254 		/*
255 		 * This is somewhat tricky: since the character set is
256 		 * potentially huge, we need to avoid allocating a map
257 		 * entry for every character. Our strategy is to set the
258 		 * default mapping to the last character of string #2
259 		 * (= the one that gets automatically repeated), then to
260 		 * add back identity mappings for characters that should
261 		 * remain unchanged. We don't waste space on identity mappings
262 		 * for non-characters with the -C option; those are simulated
263 		 * in the I/O loop.
264 		 */
265 		s2.str = argv[1];
266 		s2.state = NORMAL;
267 		for (cnt = 0; cnt < WINT_MAX; cnt++) {
268 			if (Cflag && !iswrune(cnt))
269 				continue;
270 			if (cmap_lookup(map, cnt) == OOBCH) {
271 				if (next(&s2)) {
272 					cmap_add(map, cnt, s2.lastch);
273 					if (sflag)
274 						cset_add(squeeze, s2.lastch);
275 				}
276 			} else
277 				cmap_add(map, cnt, cnt);
278 			if ((s2.state == EOS || s2.state == INFINITE) &&
279 			    cnt >= cmap_max(map))
280 				break;
281 		}
282 		cmap_default(map, s2.lastch);
283 	} else if (Cflag) {
284 		for (p = carray, cnt = 0; cnt < NCHARS_SB; cnt++) {
285 			if (cmap_lookup(map, cnt) == OOBCH && iswrune(cnt))
286 				*p++ = cnt;
287 			else
288 				cmap_add(map, cnt, cnt);
289 		}
290 		n = p - carray;
291 		if (Cflag && n > 1)
292 			(void)mergesort(carray, n, sizeof(*carray), charcoll);
293 
294 		s2.str = argv[1];
295 		s2.state = NORMAL;
296 		for (cnt = 0; cnt < n; cnt++) {
297 			(void)next(&s2);
298 			cmap_add(map, carray[cnt], s2.lastch);
299 			/*
300 			 * Chars taken from s2 can be different this time
301 			 * due to lack of complex upper/lower processing,
302 			 * so fill string2 again to not miss some.
303 			 */
304 			if (sflag)
305 				cset_add(squeeze, s2.lastch);
306 		}
307 	}
308 
309 	cset_cache(squeeze);
310 	cmap_cache(map);
311 
312 	if (sflag)
313 		for (lastch = OOBCH; (ch = getwchar()) != WEOF;) {
314 			if (!Cflag || iswrune(ch))
315 				ch = cmap_lookup(map, ch);
316 			if (lastch != ch || !cset_in(squeeze, ch)) {
317 				lastch = ch;
318 				(void)putwchar(ch);
319 			}
320 		}
321 	else
322 		while ((ch = getwchar()) != WEOF) {
323 			if (!Cflag || iswrune(ch))
324 				ch = cmap_lookup(map, ch);
325 			(void)putwchar(ch);
326 		}
327 	if (ferror(stdin))
328 		err(1, NULL);
329 	exit (0);
330 }
331 
332 static struct cset *
333 setup(char *arg, STR *str, int cflag, int Cflag)
334 {
335 	struct cset *cs;
336 
337 	cs = cset_alloc();
338 	if (cs == NULL)
339 		err(1, NULL);
340 	str->str = arg;
341 	while (next(str))
342 		cset_add(cs, str->lastch);
343 	if (Cflag)
344 		cset_addclass(cs, wctype("rune"), true);
345 	if (cflag || Cflag)
346 		cset_invert(cs);
347 	cset_cache(cs);
348 	return (cs);
349 }
350 
351 int
352 charcoll(const void *a, const void *b)
353 {
354 	static char sa[2], sb[2];
355 
356 	sa[0] = *(const int *)a;
357 	sb[0] = *(const int *)b;
358 	return (strcoll(sa, sb));
359 }
360 
361 static void
362 usage(void)
363 {
364 	(void)fprintf(stderr, "%s\n%s\n%s\n%s\n",
365 		"usage: tr [-Ccsu] string1 string2",
366 		"       tr [-Ccu] -d string1",
367 		"       tr [-Ccu] -s string1",
368 		"       tr [-Ccu] -ds string1 string2");
369 	exit(1);
370 }
371