xref: /freebsd/usr.bin/cut/cut.c (revision 3c4ba5f55438f7afd4f4b0b56f88f2bb505fd6a6)
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 	/* reversed range with autostart */
214 	if (maxval < autostart) {
215 		maxval = autostart;
216 		needpos(maxval + 1);
217 	}
218 
219 	/* set autostart */
220 	if (autostart)
221 		memset(positions + 1, '1', autostart);
222 }
223 
224 static void
225 needpos(size_t n)
226 {
227 	static size_t npos;
228 	size_t oldnpos;
229 
230 	/* Grow the positions array to at least the specified size. */
231 	if (n > npos) {
232 		oldnpos = npos;
233 		if (npos == 0)
234 			npos = n;
235 		while (n > npos)
236 			npos *= 2;
237 		if ((positions = realloc(positions, npos)) == NULL)
238 			err(1, "realloc");
239 		memset((char *)positions + oldnpos, 0, npos - oldnpos);
240 	}
241 }
242 
243 static int
244 b_cut(FILE *fp, const char *fname __unused)
245 {
246 	int ch, col;
247 	char *pos;
248 
249 	ch = 0;
250 	for (;;) {
251 		pos = positions + 1;
252 		for (col = maxval; col; --col) {
253 			if ((ch = getc(fp)) == EOF)
254 				return (0);
255 			if (ch == '\n')
256 				break;
257 			if (*pos++)
258 				(void)putchar(ch);
259 		}
260 		if (ch != '\n') {
261 			if (autostop)
262 				while ((ch = getc(fp)) != EOF && ch != '\n')
263 					(void)putchar(ch);
264 			else
265 				while ((ch = getc(fp)) != EOF && ch != '\n');
266 		}
267 		(void)putchar('\n');
268 	}
269 	return (0);
270 }
271 
272 /*
273  * Cut based on byte positions, taking care not to split multibyte characters.
274  * Although this function also handles the case where -n is not specified,
275  * b_cut() ought to be much faster.
276  */
277 static int
278 b_n_cut(FILE *fp, const char *fname)
279 {
280 	size_t col, i, lbuflen;
281 	char *lbuf;
282 	int canwrite, clen, warned;
283 	mbstate_t mbs;
284 
285 	memset(&mbs, 0, sizeof(mbs));
286 	warned = 0;
287 	while ((lbuf = fgetln(fp, &lbuflen)) != NULL) {
288 		for (col = 0; lbuflen > 0; col += clen) {
289 			if ((clen = mbrlen(lbuf, lbuflen, &mbs)) < 0) {
290 				if (!warned) {
291 					warn("%s", fname);
292 					warned = 1;
293 				}
294 				memset(&mbs, 0, sizeof(mbs));
295 				clen = 1;
296 			}
297 			if (clen == 0 || *lbuf == '\n')
298 				break;
299 			if (col < maxval && !positions[1 + col]) {
300 				/*
301 				 * Print the character if (1) after an initial
302 				 * segment of un-selected bytes, the rest of
303 				 * it is selected, and (2) the last byte is
304 				 * selected.
305 				 */
306 				i = col;
307 				while (i < col + clen && i < maxval &&
308 				    !positions[1 + i])
309 					i++;
310 				canwrite = i < col + clen;
311 				for (; i < col + clen && i < maxval; i++)
312 					canwrite &= positions[1 + i];
313 				if (canwrite)
314 					fwrite(lbuf, 1, clen, stdout);
315 			} else {
316 				/*
317 				 * Print the character if all of it has
318 				 * been selected.
319 				 */
320 				canwrite = 1;
321 				for (i = col; i < col + clen; i++)
322 					if ((i >= maxval && !autostop) ||
323 					    (i < maxval && !positions[1 + i])) {
324 						canwrite = 0;
325 						break;
326 					}
327 				if (canwrite)
328 					fwrite(lbuf, 1, clen, stdout);
329 			}
330 			lbuf += clen;
331 			lbuflen -= clen;
332 		}
333 		if (lbuflen > 0)
334 			putchar('\n');
335 	}
336 	return (warned);
337 }
338 
339 static int
340 c_cut(FILE *fp, const char *fname)
341 {
342 	wint_t ch;
343 	int col;
344 	char *pos;
345 
346 	ch = 0;
347 	for (;;) {
348 		pos = positions + 1;
349 		for (col = maxval; col; --col) {
350 			if ((ch = getwc(fp)) == WEOF)
351 				goto out;
352 			if (ch == '\n')
353 				break;
354 			if (*pos++)
355 				(void)putwchar(ch);
356 		}
357 		if (ch != '\n') {
358 			if (autostop)
359 				while ((ch = getwc(fp)) != WEOF && ch != '\n')
360 					(void)putwchar(ch);
361 			else
362 				while ((ch = getwc(fp)) != WEOF && ch != '\n');
363 		}
364 		(void)putwchar('\n');
365 	}
366 out:
367 	if (ferror(fp)) {
368 		warn("%s", fname);
369 		return (1);
370 	}
371 	return (0);
372 }
373 
374 static int
375 is_delim(wchar_t ch)
376 {
377 	if (wflag) {
378 		if (ch == ' ' || ch == '\t')
379 			return 1;
380 	} else {
381 		if (ch == dchar)
382 			return 1;
383 	}
384 	return 0;
385 }
386 
387 static int
388 f_cut(FILE *fp, const char *fname)
389 {
390 	wchar_t ch;
391 	int field, i, isdelim;
392 	char *pos, *p;
393 	int output;
394 	char *lbuf, *mlbuf;
395 	size_t clen, lbuflen, reallen;
396 
397 	mlbuf = NULL;
398 	while ((lbuf = fgetln(fp, &lbuflen)) != NULL) {
399 		reallen = lbuflen;
400 		/* Assert EOL has a newline. */
401 		if (*(lbuf + lbuflen - 1) != '\n') {
402 			/* Can't have > 1 line with no trailing newline. */
403 			mlbuf = malloc(lbuflen + 1);
404 			if (mlbuf == NULL)
405 				err(1, "malloc");
406 			memcpy(mlbuf, lbuf, lbuflen);
407 			*(mlbuf + lbuflen) = '\n';
408 			lbuf = mlbuf;
409 			reallen++;
410 		}
411 		output = 0;
412 		for (isdelim = 0, p = lbuf;; p += clen) {
413 			clen = mbrtowc(&ch, p, lbuf + reallen - p, NULL);
414 			if (clen == (size_t)-1 || clen == (size_t)-2) {
415 				warnc(EILSEQ, "%s", fname);
416 				free(mlbuf);
417 				return (1);
418 			}
419 			if (clen == 0)
420 				clen = 1;
421 			/* this should work if newline is delimiter */
422 			if (is_delim(ch))
423 				isdelim = 1;
424 			if (ch == '\n') {
425 				if (!isdelim && !sflag)
426 					(void)fwrite(lbuf, lbuflen, 1, stdout);
427 				break;
428 			}
429 		}
430 		if (!isdelim)
431 			continue;
432 
433 		pos = positions + 1;
434 		for (field = maxval, p = lbuf; field; --field, ++pos) {
435 			if (*pos && output++)
436 				for (i = 0; dcharmb[i] != '\0'; i++)
437 					putchar(dcharmb[i]);
438 			for (;;) {
439 				clen = mbrtowc(&ch, p, lbuf + reallen - p,
440 				    NULL);
441 				if (clen == (size_t)-1 || clen == (size_t)-2) {
442 					warnc(EILSEQ, "%s", fname);
443 					free(mlbuf);
444 					return (1);
445 				}
446 				if (clen == 0)
447 					clen = 1;
448 				p += clen;
449 				if (ch == '\n' || is_delim(ch)) {
450 					/* compress whitespace */
451 					if (wflag && ch != '\n')
452 						while (is_delim(*p))
453 							p++;
454 					break;
455 				}
456 				if (*pos)
457 					for (i = 0; i < (int)clen; i++)
458 						putchar(p[i - clen]);
459 			}
460 			if (ch == '\n')
461 				break;
462 		}
463 		if (ch != '\n') {
464 			if (autostop) {
465 				if (output)
466 					for (i = 0; dcharmb[i] != '\0'; i++)
467 						putchar(dcharmb[i]);
468 				for (; (ch = *p) != '\n'; ++p)
469 					(void)putchar(ch);
470 			} else
471 				for (; (ch = *p) != '\n'; ++p);
472 		}
473 		(void)putchar('\n');
474 	}
475 	free(mlbuf);
476 	return (0);
477 }
478 
479 static void
480 usage(void)
481 {
482 	(void)fprintf(stderr, "%s\n%s\n%s\n",
483 		"usage: cut -b list [-n] [file ...]",
484 		"       cut -c list [file ...]",
485 		"       cut -f list [-s] [-w | -d delim] [file ...]");
486 	exit(1);
487 }
488