xref: /freebsd/usr.bin/cut/cut.c (revision f5147e312f43a9050468de539aeafa072caa1a60)
1 /*
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1989, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * This code is derived from software contributed to Berkeley by
8  * Adam S. Moskowitz of Menlo Consulting and Marciano Pitargue.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. Neither the name of the University nor the names of its contributors
19  *    may be used to endorse or promote products derived from this software
20  *    without specific prior written permission.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32  * SUCH DAMAGE.
33  */
34 
35 #ifndef lint
36 static const char copyright[] =
37 "@(#) Copyright (c) 1989, 1993\n\
38 	The Regents of the University of California.  All rights reserved.\n";
39 static const char sccsid[] = "@(#)cut.c	8.3 (Berkeley) 5/4/95";
40 #endif /* not lint */
41 #include <sys/cdefs.h>
42 __FBSDID("$FreeBSD$");
43 
44 #include <ctype.h>
45 #include <err.h>
46 #include <errno.h>
47 #include <limits.h>
48 #include <locale.h>
49 #include <stdio.h>
50 #include <stdlib.h>
51 #include <string.h>
52 #include <unistd.h>
53 #include <wchar.h>
54 
55 static int	bflag;
56 static int	cflag;
57 static wchar_t	dchar;
58 static char	dcharmb[MB_LEN_MAX + 1];
59 static int	dflag;
60 static int	fflag;
61 static int	nflag;
62 static int	sflag;
63 static int	wflag;
64 
65 static size_t	autostart, autostop, maxval;
66 static char *	positions;
67 
68 static int	b_cut(FILE *, const char *);
69 static int	b_n_cut(FILE *, const char *);
70 static int	c_cut(FILE *, const char *);
71 static int	f_cut(FILE *, const char *);
72 static void	get_list(char *);
73 static int	is_delim(wchar_t);
74 static void	needpos(size_t);
75 static void	usage(void);
76 
77 int
78 main(int argc, char *argv[])
79 {
80 	FILE *fp;
81 	int (*fcn)(FILE *, const char *);
82 	int ch, rval;
83 	size_t n;
84 
85 	setlocale(LC_ALL, "");
86 
87 	fcn = NULL;
88 	dchar = '\t';			/* default delimiter is \t */
89 	strcpy(dcharmb, "\t");
90 
91 	while ((ch = getopt(argc, argv, "b:c:d:f:snw")) != -1)
92 		switch(ch) {
93 		case 'b':
94 			get_list(optarg);
95 			bflag = 1;
96 			break;
97 		case 'c':
98 			get_list(optarg);
99 			cflag = 1;
100 			break;
101 		case 'd':
102 			n = mbrtowc(&dchar, optarg, MB_LEN_MAX, NULL);
103 			if (dchar == '\0' || n != strlen(optarg))
104 				errx(1, "bad delimiter");
105 			strcpy(dcharmb, optarg);
106 			dflag = 1;
107 			break;
108 		case 'f':
109 			get_list(optarg);
110 			fflag = 1;
111 			break;
112 		case 's':
113 			sflag = 1;
114 			break;
115 		case 'n':
116 			nflag = 1;
117 			break;
118 		case 'w':
119 			wflag = 1;
120 			break;
121 		case '?':
122 		default:
123 			usage();
124 		}
125 	argc -= optind;
126 	argv += optind;
127 
128 	if (fflag) {
129 		if (bflag || cflag || nflag || (wflag && dflag))
130 			usage();
131 	} else if (!(bflag || cflag) || dflag || sflag || wflag)
132 		usage();
133 	else if (!bflag && nflag)
134 		usage();
135 
136 	if (fflag)
137 		fcn = f_cut;
138 	else if (cflag)
139 		fcn = MB_CUR_MAX > 1 ? c_cut : b_cut;
140 	else if (bflag)
141 		fcn = nflag && MB_CUR_MAX > 1 ? b_n_cut : b_cut;
142 
143 	rval = 0;
144 	if (*argv)
145 		for (; *argv; ++argv) {
146 			if (strcmp(*argv, "-") == 0)
147 				rval |= fcn(stdin, "stdin");
148 			else {
149 				if (!(fp = fopen(*argv, "r"))) {
150 					warn("%s", *argv);
151 					rval = 1;
152 					continue;
153 				}
154 				fcn(fp, *argv);
155 				(void)fclose(fp);
156 			}
157 		}
158 	else
159 		rval = fcn(stdin, "stdin");
160 	exit(rval);
161 }
162 
163 static void
164 get_list(char *list)
165 {
166 	size_t setautostart, start, stop;
167 	char *pos;
168 	char *p;
169 
170 	/*
171 	 * set a byte in the positions array to indicate if a field or
172 	 * column is to be selected; use +1, it's 1-based, not 0-based.
173 	 * Numbers and number ranges may be overlapping, repeated, and in
174 	 * any order. We handle "-3-5" although there's no real reason to.
175 	 */
176 	for (; (p = strsep(&list, ", \t")) != NULL;) {
177 		setautostart = start = stop = 0;
178 		if (*p == '-') {
179 			++p;
180 			setautostart = 1;
181 		}
182 		if (isdigit((unsigned char)*p)) {
183 			start = stop = strtol(p, &p, 10);
184 			if (setautostart && start > autostart)
185 				autostart = start;
186 		}
187 		if (*p == '-') {
188 			if (isdigit((unsigned char)p[1]))
189 				stop = strtol(p + 1, &p, 10);
190 			if (*p == '-') {
191 				++p;
192 				if (!autostop || autostop > stop)
193 					autostop = stop;
194 			}
195 		}
196 		if (*p)
197 			errx(1, "[-bcf] list: illegal list value");
198 		if (!stop || !start)
199 			errx(1, "[-bcf] list: values may not include zero");
200 		if (maxval < stop) {
201 			maxval = stop;
202 			needpos(maxval + 1);
203 		}
204 		for (pos = positions + start; start++ <= stop; *pos++ = 1);
205 	}
206 
207 	/* overlapping ranges */
208 	if (autostop && maxval > autostop) {
209 		maxval = autostop;
210 		needpos(maxval + 1);
211 	}
212 
213 	/* set autostart */
214 	if (autostart)
215 		memset(positions + 1, '1', autostart);
216 }
217 
218 static void
219 needpos(size_t n)
220 {
221 	static size_t npos;
222 	size_t oldnpos;
223 
224 	/* Grow the positions array to at least the specified size. */
225 	if (n > npos) {
226 		oldnpos = npos;
227 		if (npos == 0)
228 			npos = n;
229 		while (n > npos)
230 			npos *= 2;
231 		if ((positions = realloc(positions, npos)) == NULL)
232 			err(1, "realloc");
233 		memset((char *)positions + oldnpos, 0, npos - oldnpos);
234 	}
235 }
236 
237 static int
238 b_cut(FILE *fp, const char *fname __unused)
239 {
240 	int ch, col;
241 	char *pos;
242 
243 	ch = 0;
244 	for (;;) {
245 		pos = positions + 1;
246 		for (col = maxval; col; --col) {
247 			if ((ch = getc(fp)) == EOF)
248 				return (0);
249 			if (ch == '\n')
250 				break;
251 			if (*pos++)
252 				(void)putchar(ch);
253 		}
254 		if (ch != '\n') {
255 			if (autostop)
256 				while ((ch = getc(fp)) != EOF && ch != '\n')
257 					(void)putchar(ch);
258 			else
259 				while ((ch = getc(fp)) != EOF && ch != '\n');
260 		}
261 		(void)putchar('\n');
262 	}
263 	return (0);
264 }
265 
266 /*
267  * Cut based on byte positions, taking care not to split multibyte characters.
268  * Although this function also handles the case where -n is not specified,
269  * b_cut() ought to be much faster.
270  */
271 static int
272 b_n_cut(FILE *fp, const char *fname)
273 {
274 	size_t col, i, lbuflen;
275 	char *lbuf;
276 	int canwrite, clen, warned;
277 	mbstate_t mbs;
278 
279 	memset(&mbs, 0, sizeof(mbs));
280 	warned = 0;
281 	while ((lbuf = fgetln(fp, &lbuflen)) != NULL) {
282 		for (col = 0; lbuflen > 0; col += clen) {
283 			if ((clen = mbrlen(lbuf, lbuflen, &mbs)) < 0) {
284 				if (!warned) {
285 					warn("%s", fname);
286 					warned = 1;
287 				}
288 				memset(&mbs, 0, sizeof(mbs));
289 				clen = 1;
290 			}
291 			if (clen == 0 || *lbuf == '\n')
292 				break;
293 			if (col < maxval && !positions[1 + col]) {
294 				/*
295 				 * Print the character if (1) after an initial
296 				 * segment of un-selected bytes, the rest of
297 				 * it is selected, and (2) the last byte is
298 				 * selected.
299 				 */
300 				i = col;
301 				while (i < col + clen && i < maxval &&
302 				    !positions[1 + i])
303 					i++;
304 				canwrite = i < col + clen;
305 				for (; i < col + clen && i < maxval; i++)
306 					canwrite &= positions[1 + i];
307 				if (canwrite)
308 					fwrite(lbuf, 1, clen, stdout);
309 			} else {
310 				/*
311 				 * Print the character if all of it has
312 				 * been selected.
313 				 */
314 				canwrite = 1;
315 				for (i = col; i < col + clen; i++)
316 					if ((i >= maxval && !autostop) ||
317 					    (i < maxval && !positions[1 + i])) {
318 						canwrite = 0;
319 						break;
320 					}
321 				if (canwrite)
322 					fwrite(lbuf, 1, clen, stdout);
323 			}
324 			lbuf += clen;
325 			lbuflen -= clen;
326 		}
327 		if (lbuflen > 0)
328 			putchar('\n');
329 	}
330 	return (warned);
331 }
332 
333 static int
334 c_cut(FILE *fp, const char *fname)
335 {
336 	wint_t ch;
337 	int col;
338 	char *pos;
339 
340 	ch = 0;
341 	for (;;) {
342 		pos = positions + 1;
343 		for (col = maxval; col; --col) {
344 			if ((ch = getwc(fp)) == WEOF)
345 				goto out;
346 			if (ch == '\n')
347 				break;
348 			if (*pos++)
349 				(void)putwchar(ch);
350 		}
351 		if (ch != '\n') {
352 			if (autostop)
353 				while ((ch = getwc(fp)) != WEOF && ch != '\n')
354 					(void)putwchar(ch);
355 			else
356 				while ((ch = getwc(fp)) != WEOF && ch != '\n');
357 		}
358 		(void)putwchar('\n');
359 	}
360 out:
361 	if (ferror(fp)) {
362 		warn("%s", fname);
363 		return (1);
364 	}
365 	return (0);
366 }
367 
368 static int
369 is_delim(wchar_t ch)
370 {
371 	if (wflag) {
372 		if (ch == ' ' || ch == '\t')
373 			return 1;
374 	} else {
375 		if (ch == dchar)
376 			return 1;
377 	}
378 	return 0;
379 }
380 
381 static int
382 f_cut(FILE *fp, const char *fname)
383 {
384 	wchar_t ch;
385 	int field, i, isdelim;
386 	char *pos, *p;
387 	int output;
388 	char *lbuf, *mlbuf;
389 	size_t clen, lbuflen, reallen;
390 
391 	mlbuf = NULL;
392 	while ((lbuf = fgetln(fp, &lbuflen)) != NULL) {
393 		reallen = lbuflen;
394 		/* Assert EOL has a newline. */
395 		if (*(lbuf + lbuflen - 1) != '\n') {
396 			/* Can't have > 1 line with no trailing newline. */
397 			mlbuf = malloc(lbuflen + 1);
398 			if (mlbuf == NULL)
399 				err(1, "malloc");
400 			memcpy(mlbuf, lbuf, lbuflen);
401 			*(mlbuf + lbuflen) = '\n';
402 			lbuf = mlbuf;
403 			reallen++;
404 		}
405 		output = 0;
406 		for (isdelim = 0, p = lbuf;; p += clen) {
407 			clen = mbrtowc(&ch, p, lbuf + reallen - p, NULL);
408 			if (clen == (size_t)-1 || clen == (size_t)-2) {
409 				warnc(EILSEQ, "%s", fname);
410 				free(mlbuf);
411 				return (1);
412 			}
413 			if (clen == 0)
414 				clen = 1;
415 			/* this should work if newline is delimiter */
416 			if (is_delim(ch))
417 				isdelim = 1;
418 			if (ch == '\n') {
419 				if (!isdelim && !sflag)
420 					(void)fwrite(lbuf, lbuflen, 1, stdout);
421 				break;
422 			}
423 		}
424 		if (!isdelim)
425 			continue;
426 
427 		pos = positions + 1;
428 		for (field = maxval, p = lbuf; field; --field, ++pos) {
429 			if (*pos && output++)
430 				for (i = 0; dcharmb[i] != '\0'; i++)
431 					putchar(dcharmb[i]);
432 			for (;;) {
433 				clen = mbrtowc(&ch, p, lbuf + reallen - p,
434 				    NULL);
435 				if (clen == (size_t)-1 || clen == (size_t)-2) {
436 					warnc(EILSEQ, "%s", fname);
437 					free(mlbuf);
438 					return (1);
439 				}
440 				if (clen == 0)
441 					clen = 1;
442 				p += clen;
443 				if (ch == '\n' || is_delim(ch)) {
444 					/* compress whitespace */
445 					if (wflag && ch != '\n')
446 						while (is_delim(*p))
447 							p++;
448 					break;
449 				}
450 				if (*pos)
451 					for (i = 0; i < (int)clen; i++)
452 						putchar(p[i - clen]);
453 			}
454 			if (ch == '\n')
455 				break;
456 		}
457 		if (ch != '\n') {
458 			if (autostop) {
459 				if (output)
460 					for (i = 0; dcharmb[i] != '\0'; i++)
461 						putchar(dcharmb[i]);
462 				for (; (ch = *p) != '\n'; ++p)
463 					(void)putchar(ch);
464 			} else
465 				for (; (ch = *p) != '\n'; ++p);
466 		}
467 		(void)putchar('\n');
468 	}
469 	free(mlbuf);
470 	return (0);
471 }
472 
473 static void
474 usage(void)
475 {
476 	(void)fprintf(stderr, "%s\n%s\n%s\n",
477 		"usage: cut -b list [-n] [file ...]",
478 		"       cut -c list [file ...]",
479 		"       cut -f list [-s] [-w | -d delim] [file ...]");
480 	exit(1);
481 }
482