xref: /freebsd/usr.bin/cut/cut.c (revision 5e3190f700637fcfc1a52daeaa4a031fdd2557c7)
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 #include <ctype.h>
43 #include <err.h>
44 #include <errno.h>
45 #include <limits.h>
46 #include <locale.h>
47 #include <stdio.h>
48 #include <stdlib.h>
49 #include <string.h>
50 #include <unistd.h>
51 #include <wchar.h>
52 
53 static int	bflag;
54 static int	cflag;
55 static wchar_t	dchar;
56 static char	dcharmb[MB_LEN_MAX + 1];
57 static int	dflag;
58 static int	fflag;
59 static int	nflag;
60 static int	sflag;
61 static int	wflag;
62 
63 static size_t	autostart, autostop, maxval;
64 static char *	positions;
65 
66 static int	b_cut(FILE *, const char *);
67 static int	b_n_cut(FILE *, const char *);
68 static int	c_cut(FILE *, const char *);
69 static int	f_cut(FILE *, const char *);
70 static void	get_list(char *);
71 static int	is_delim(wchar_t);
72 static void	needpos(size_t);
73 static void	usage(void);
74 
75 int
76 main(int argc, char *argv[])
77 {
78 	FILE *fp;
79 	int (*fcn)(FILE *, const char *);
80 	int ch, rval;
81 	size_t n;
82 
83 	setlocale(LC_ALL, "");
84 
85 	fcn = NULL;
86 	dchar = '\t';			/* default delimiter is \t */
87 	strcpy(dcharmb, "\t");
88 
89 	while ((ch = getopt(argc, argv, "b:c:d:f:snw")) != -1)
90 		switch(ch) {
91 		case 'b':
92 			get_list(optarg);
93 			bflag = 1;
94 			break;
95 		case 'c':
96 			get_list(optarg);
97 			cflag = 1;
98 			break;
99 		case 'd':
100 			n = mbrtowc(&dchar, optarg, MB_LEN_MAX, NULL);
101 			if (dchar == '\0' || n != strlen(optarg))
102 				errx(1, "bad delimiter");
103 			strcpy(dcharmb, optarg);
104 			dflag = 1;
105 			break;
106 		case 'f':
107 			get_list(optarg);
108 			fflag = 1;
109 			break;
110 		case 's':
111 			sflag = 1;
112 			break;
113 		case 'n':
114 			nflag = 1;
115 			break;
116 		case 'w':
117 			wflag = 1;
118 			break;
119 		case '?':
120 		default:
121 			usage();
122 		}
123 	argc -= optind;
124 	argv += optind;
125 
126 	if (fflag) {
127 		if (bflag || cflag || nflag || (wflag && dflag))
128 			usage();
129 	} else if (!(bflag || cflag) || dflag || sflag || wflag)
130 		usage();
131 	else if (!bflag && nflag)
132 		usage();
133 
134 	if (fflag)
135 		fcn = f_cut;
136 	else if (cflag)
137 		fcn = MB_CUR_MAX > 1 ? c_cut : b_cut;
138 	else if (bflag)
139 		fcn = nflag && MB_CUR_MAX > 1 ? b_n_cut : b_cut;
140 
141 	rval = 0;
142 	if (*argv)
143 		for (; *argv; ++argv) {
144 			if (strcmp(*argv, "-") == 0)
145 				rval |= fcn(stdin, "stdin");
146 			else {
147 				if (!(fp = fopen(*argv, "r"))) {
148 					warn("%s", *argv);
149 					rval = 1;
150 					continue;
151 				}
152 				fcn(fp, *argv);
153 				(void)fclose(fp);
154 			}
155 		}
156 	else
157 		rval = fcn(stdin, "stdin");
158 	exit(rval);
159 }
160 
161 static void
162 get_list(char *list)
163 {
164 	size_t setautostart, start, stop;
165 	char *pos;
166 	char *p;
167 
168 	/*
169 	 * set a byte in the positions array to indicate if a field or
170 	 * column is to be selected; use +1, it's 1-based, not 0-based.
171 	 * Numbers and number ranges may be overlapping, repeated, and in
172 	 * any order. We handle "-3-5" although there's no real reason to.
173 	 */
174 	for (; (p = strsep(&list, ", \t")) != NULL;) {
175 		setautostart = start = stop = 0;
176 		if (*p == '-') {
177 			++p;
178 			setautostart = 1;
179 		}
180 		if (isdigit((unsigned char)*p)) {
181 			start = stop = strtol(p, &p, 10);
182 			if (setautostart && start > autostart)
183 				autostart = start;
184 		}
185 		if (*p == '-') {
186 			if (isdigit((unsigned char)p[1]))
187 				stop = strtol(p + 1, &p, 10);
188 			if (*p == '-') {
189 				++p;
190 				if (!autostop || autostop > stop)
191 					autostop = stop;
192 			}
193 		}
194 		if (*p)
195 			errx(1, "[-bcf] list: illegal list value");
196 		if (!stop || !start)
197 			errx(1, "[-bcf] list: values may not include zero");
198 		if (maxval < stop) {
199 			maxval = stop;
200 			needpos(maxval + 1);
201 		}
202 		for (pos = positions + start; start++ <= stop; *pos++ = 1);
203 	}
204 
205 	/* overlapping ranges */
206 	if (autostop && maxval > autostop) {
207 		maxval = autostop;
208 		needpos(maxval + 1);
209 	}
210 
211 	/* reversed range with autostart */
212 	if (maxval < autostart) {
213 		maxval = autostart;
214 		needpos(maxval + 1);
215 	}
216 
217 	/* set autostart */
218 	if (autostart)
219 		memset(positions + 1, '1', autostart);
220 }
221 
222 static void
223 needpos(size_t n)
224 {
225 	static size_t npos;
226 	size_t oldnpos;
227 
228 	/* Grow the positions array to at least the specified size. */
229 	if (n > npos) {
230 		oldnpos = npos;
231 		if (npos == 0)
232 			npos = n;
233 		while (n > npos)
234 			npos *= 2;
235 		if ((positions = realloc(positions, npos)) == NULL)
236 			err(1, "realloc");
237 		memset((char *)positions + oldnpos, 0, npos - oldnpos);
238 	}
239 }
240 
241 static int
242 b_cut(FILE *fp, const char *fname __unused)
243 {
244 	int ch, col;
245 	char *pos;
246 
247 	ch = 0;
248 	for (;;) {
249 		pos = positions + 1;
250 		for (col = maxval; col; --col) {
251 			if ((ch = getc(fp)) == EOF)
252 				return (0);
253 			if (ch == '\n')
254 				break;
255 			if (*pos++)
256 				(void)putchar(ch);
257 		}
258 		if (ch != '\n') {
259 			if (autostop)
260 				while ((ch = getc(fp)) != EOF && ch != '\n')
261 					(void)putchar(ch);
262 			else
263 				while ((ch = getc(fp)) != EOF && ch != '\n');
264 		}
265 		(void)putchar('\n');
266 	}
267 	return (0);
268 }
269 
270 /*
271  * Cut based on byte positions, taking care not to split multibyte characters.
272  * Although this function also handles the case where -n is not specified,
273  * b_cut() ought to be much faster.
274  */
275 static int
276 b_n_cut(FILE *fp, const char *fname)
277 {
278 	size_t col, i, lbuflen;
279 	char *lbuf;
280 	int canwrite, clen, warned;
281 	mbstate_t mbs;
282 
283 	memset(&mbs, 0, sizeof(mbs));
284 	warned = 0;
285 	while ((lbuf = fgetln(fp, &lbuflen)) != NULL) {
286 		for (col = 0; lbuflen > 0; col += clen) {
287 			if ((clen = mbrlen(lbuf, lbuflen, &mbs)) < 0) {
288 				if (!warned) {
289 					warn("%s", fname);
290 					warned = 1;
291 				}
292 				memset(&mbs, 0, sizeof(mbs));
293 				clen = 1;
294 			}
295 			if (clen == 0 || *lbuf == '\n')
296 				break;
297 			if (col < maxval && !positions[1 + col]) {
298 				/*
299 				 * Print the character if (1) after an initial
300 				 * segment of un-selected bytes, the rest of
301 				 * it is selected, and (2) the last byte is
302 				 * selected.
303 				 */
304 				i = col;
305 				while (i < col + clen && i < maxval &&
306 				    !positions[1 + i])
307 					i++;
308 				canwrite = i < col + clen;
309 				for (; i < col + clen && i < maxval; i++)
310 					canwrite &= positions[1 + i];
311 				if (canwrite)
312 					fwrite(lbuf, 1, clen, stdout);
313 			} else {
314 				/*
315 				 * Print the character if all of it has
316 				 * been selected.
317 				 */
318 				canwrite = 1;
319 				for (i = col; i < col + clen; i++)
320 					if ((i >= maxval && !autostop) ||
321 					    (i < maxval && !positions[1 + i])) {
322 						canwrite = 0;
323 						break;
324 					}
325 				if (canwrite)
326 					fwrite(lbuf, 1, clen, stdout);
327 			}
328 			lbuf += clen;
329 			lbuflen -= clen;
330 		}
331 		if (lbuflen > 0)
332 			putchar('\n');
333 	}
334 	return (warned);
335 }
336 
337 static int
338 c_cut(FILE *fp, const char *fname)
339 {
340 	wint_t ch;
341 	int col;
342 	char *pos;
343 
344 	ch = 0;
345 	for (;;) {
346 		pos = positions + 1;
347 		for (col = maxval; col; --col) {
348 			if ((ch = getwc(fp)) == WEOF)
349 				goto out;
350 			if (ch == '\n')
351 				break;
352 			if (*pos++)
353 				(void)putwchar(ch);
354 		}
355 		if (ch != '\n') {
356 			if (autostop)
357 				while ((ch = getwc(fp)) != WEOF && ch != '\n')
358 					(void)putwchar(ch);
359 			else
360 				while ((ch = getwc(fp)) != WEOF && ch != '\n');
361 		}
362 		(void)putwchar('\n');
363 	}
364 out:
365 	if (ferror(fp)) {
366 		warn("%s", fname);
367 		return (1);
368 	}
369 	return (0);
370 }
371 
372 static int
373 is_delim(wchar_t ch)
374 {
375 	if (wflag) {
376 		if (ch == ' ' || ch == '\t')
377 			return 1;
378 	} else {
379 		if (ch == dchar)
380 			return 1;
381 	}
382 	return 0;
383 }
384 
385 static int
386 f_cut(FILE *fp, const char *fname)
387 {
388 	wchar_t ch;
389 	int field, i, isdelim;
390 	char *pos, *p;
391 	int output;
392 	char *lbuf, *mlbuf;
393 	size_t clen, lbuflen, reallen;
394 
395 	mlbuf = NULL;
396 	while ((lbuf = fgetln(fp, &lbuflen)) != NULL) {
397 		reallen = lbuflen;
398 		/* Assert EOL has a newline. */
399 		if (*(lbuf + lbuflen - 1) != '\n') {
400 			/* Can't have > 1 line with no trailing newline. */
401 			mlbuf = malloc(lbuflen + 1);
402 			if (mlbuf == NULL)
403 				err(1, "malloc");
404 			memcpy(mlbuf, lbuf, lbuflen);
405 			*(mlbuf + lbuflen) = '\n';
406 			lbuf = mlbuf;
407 			reallen++;
408 		}
409 		output = 0;
410 		for (isdelim = 0, p = lbuf;; p += clen) {
411 			clen = mbrtowc(&ch, p, lbuf + reallen - p, NULL);
412 			if (clen == (size_t)-1 || clen == (size_t)-2) {
413 				warnc(EILSEQ, "%s", fname);
414 				free(mlbuf);
415 				return (1);
416 			}
417 			if (clen == 0)
418 				clen = 1;
419 			/* this should work if newline is delimiter */
420 			if (is_delim(ch))
421 				isdelim = 1;
422 			if (ch == '\n') {
423 				if (!isdelim && !sflag)
424 					(void)fwrite(lbuf, lbuflen, 1, stdout);
425 				break;
426 			}
427 		}
428 		if (!isdelim)
429 			continue;
430 
431 		pos = positions + 1;
432 		for (field = maxval, p = lbuf; field; --field, ++pos) {
433 			if (*pos && output++)
434 				for (i = 0; dcharmb[i] != '\0'; i++)
435 					putchar(dcharmb[i]);
436 			for (;;) {
437 				clen = mbrtowc(&ch, p, lbuf + reallen - p,
438 				    NULL);
439 				if (clen == (size_t)-1 || clen == (size_t)-2) {
440 					warnc(EILSEQ, "%s", fname);
441 					free(mlbuf);
442 					return (1);
443 				}
444 				if (clen == 0)
445 					clen = 1;
446 				p += clen;
447 				if (ch == '\n' || is_delim(ch)) {
448 					/* compress whitespace */
449 					if (wflag && ch != '\n')
450 						while (is_delim(*p))
451 							p++;
452 					break;
453 				}
454 				if (*pos)
455 					for (i = 0; i < (int)clen; i++)
456 						putchar(p[i - clen]);
457 			}
458 			if (ch == '\n')
459 				break;
460 		}
461 		if (ch != '\n') {
462 			if (autostop) {
463 				if (output)
464 					for (i = 0; dcharmb[i] != '\0'; i++)
465 						putchar(dcharmb[i]);
466 				for (; (ch = *p) != '\n'; ++p)
467 					(void)putchar(ch);
468 			} else
469 				for (; (ch = *p) != '\n'; ++p);
470 		}
471 		(void)putchar('\n');
472 	}
473 	free(mlbuf);
474 	return (0);
475 }
476 
477 static void
478 usage(void)
479 {
480 	(void)fprintf(stderr, "%s\n%s\n%s\n",
481 		"usage: cut -b list [-n] [file ...]",
482 		"       cut -c list [file ...]",
483 		"       cut -f list [-s] [-w | -d delim] [file ...]");
484 	exit(1);
485 }
486