xref: /freebsd/usr.bin/cut/cut.c (revision 57718be8fa0bd5edc11ab9a72e68cc71982939a6)
1 /*
2  * Copyright (c) 1989, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * This code is derived from software contributed to Berkeley by
6  * Adam S. Moskowitz of Menlo Consulting and Marciano Pitargue.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 4. Neither the name of the University nor the names of its contributors
17  *    may be used to endorse or promote products derived from this software
18  *    without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30  * SUCH DAMAGE.
31  */
32 
33 #ifndef lint
34 static const char copyright[] =
35 "@(#) Copyright (c) 1989, 1993\n\
36 	The Regents of the University of California.  All rights reserved.\n";
37 static const char sccsid[] = "@(#)cut.c	8.3 (Berkeley) 5/4/95";
38 #endif /* not lint */
39 #include <sys/cdefs.h>
40 __FBSDID("$FreeBSD$");
41 
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 	/* set autostart */
212 	if (autostart)
213 		memset(positions + 1, '1', autostart);
214 }
215 
216 static void
217 needpos(size_t n)
218 {
219 	static size_t npos;
220 	size_t oldnpos;
221 
222 	/* Grow the positions array to at least the specified size. */
223 	if (n > npos) {
224 		oldnpos = npos;
225 		if (npos == 0)
226 			npos = n;
227 		while (n > npos)
228 			npos *= 2;
229 		if ((positions = realloc(positions, npos)) == NULL)
230 			err(1, "realloc");
231 		memset((char *)positions + oldnpos, 0, npos - oldnpos);
232 	}
233 }
234 
235 static int
236 b_cut(FILE *fp, const char *fname __unused)
237 {
238 	int ch, col;
239 	char *pos;
240 
241 	ch = 0;
242 	for (;;) {
243 		pos = positions + 1;
244 		for (col = maxval; col; --col) {
245 			if ((ch = getc(fp)) == EOF)
246 				return (0);
247 			if (ch == '\n')
248 				break;
249 			if (*pos++)
250 				(void)putchar(ch);
251 		}
252 		if (ch != '\n') {
253 			if (autostop)
254 				while ((ch = getc(fp)) != EOF && ch != '\n')
255 					(void)putchar(ch);
256 			else
257 				while ((ch = getc(fp)) != EOF && ch != '\n');
258 		}
259 		(void)putchar('\n');
260 	}
261 	return (0);
262 }
263 
264 /*
265  * Cut based on byte positions, taking care not to split multibyte characters.
266  * Although this function also handles the case where -n is not specified,
267  * b_cut() ought to be much faster.
268  */
269 static int
270 b_n_cut(FILE *fp, const char *fname)
271 {
272 	size_t col, i, lbuflen;
273 	char *lbuf;
274 	int canwrite, clen, warned;
275 	mbstate_t mbs;
276 
277 	memset(&mbs, 0, sizeof(mbs));
278 	warned = 0;
279 	while ((lbuf = fgetln(fp, &lbuflen)) != NULL) {
280 		for (col = 0; lbuflen > 0; col += clen) {
281 			if ((clen = mbrlen(lbuf, lbuflen, &mbs)) < 0) {
282 				if (!warned) {
283 					warn("%s", fname);
284 					warned = 1;
285 				}
286 				memset(&mbs, 0, sizeof(mbs));
287 				clen = 1;
288 			}
289 			if (clen == 0 || *lbuf == '\n')
290 				break;
291 			if (col < maxval && !positions[1 + col]) {
292 				/*
293 				 * Print the character if (1) after an initial
294 				 * segment of un-selected bytes, the rest of
295 				 * it is selected, and (2) the last byte is
296 				 * selected.
297 				 */
298 				i = col;
299 				while (i < col + clen && i < maxval &&
300 				    !positions[1 + i])
301 					i++;
302 				canwrite = i < col + clen;
303 				for (; i < col + clen && i < maxval; i++)
304 					canwrite &= positions[1 + i];
305 				if (canwrite)
306 					fwrite(lbuf, 1, clen, stdout);
307 			} else {
308 				/*
309 				 * Print the character if all of it has
310 				 * been selected.
311 				 */
312 				canwrite = 1;
313 				for (i = col; i < col + clen; i++)
314 					if ((i >= maxval && !autostop) ||
315 					    (i < maxval && !positions[1 + i])) {
316 						canwrite = 0;
317 						break;
318 					}
319 				if (canwrite)
320 					fwrite(lbuf, 1, clen, stdout);
321 			}
322 			lbuf += clen;
323 			lbuflen -= clen;
324 		}
325 		if (lbuflen > 0)
326 			putchar('\n');
327 	}
328 	return (warned);
329 }
330 
331 static int
332 c_cut(FILE *fp, const char *fname)
333 {
334 	wint_t ch;
335 	int col;
336 	char *pos;
337 
338 	ch = 0;
339 	for (;;) {
340 		pos = positions + 1;
341 		for (col = maxval; col; --col) {
342 			if ((ch = getwc(fp)) == WEOF)
343 				goto out;
344 			if (ch == '\n')
345 				break;
346 			if (*pos++)
347 				(void)putwchar(ch);
348 		}
349 		if (ch != '\n') {
350 			if (autostop)
351 				while ((ch = getwc(fp)) != WEOF && ch != '\n')
352 					(void)putwchar(ch);
353 			else
354 				while ((ch = getwc(fp)) != WEOF && ch != '\n');
355 		}
356 		(void)putwchar('\n');
357 	}
358 out:
359 	if (ferror(fp)) {
360 		warn("%s", fname);
361 		return (1);
362 	}
363 	return (0);
364 }
365 
366 static int
367 is_delim(wchar_t ch)
368 {
369 	if (wflag) {
370 		if (ch == ' ' || ch == '\t')
371 			return 1;
372 	} else {
373 		if (ch == dchar)
374 			return 1;
375 	}
376 	return 0;
377 }
378 
379 static int
380 f_cut(FILE *fp, const char *fname)
381 {
382 	wchar_t ch;
383 	int field, i, isdelim;
384 	char *pos, *p;
385 	int output;
386 	char *lbuf, *mlbuf;
387 	size_t clen, lbuflen, reallen;
388 
389 	mlbuf = NULL;
390 	while ((lbuf = fgetln(fp, &lbuflen)) != NULL) {
391 		reallen = lbuflen;
392 		/* Assert EOL has a newline. */
393 		if (*(lbuf + lbuflen - 1) != '\n') {
394 			/* Can't have > 1 line with no trailing newline. */
395 			mlbuf = malloc(lbuflen + 1);
396 			if (mlbuf == NULL)
397 				err(1, "malloc");
398 			memcpy(mlbuf, lbuf, lbuflen);
399 			*(mlbuf + lbuflen) = '\n';
400 			lbuf = mlbuf;
401 			reallen++;
402 		}
403 		output = 0;
404 		for (isdelim = 0, p = lbuf;; p += clen) {
405 			clen = mbrtowc(&ch, p, lbuf + reallen - p, NULL);
406 			if (clen == (size_t)-1 || clen == (size_t)-2) {
407 				warnc(EILSEQ, "%s", fname);
408 				free(mlbuf);
409 				return (1);
410 			}
411 			if (clen == 0)
412 				clen = 1;
413 			/* this should work if newline is delimiter */
414 			if (is_delim(ch))
415 				isdelim = 1;
416 			if (ch == '\n') {
417 				if (!isdelim && !sflag)
418 					(void)fwrite(lbuf, lbuflen, 1, stdout);
419 				break;
420 			}
421 		}
422 		if (!isdelim)
423 			continue;
424 
425 		pos = positions + 1;
426 		for (field = maxval, p = lbuf; field; --field, ++pos) {
427 			if (*pos && output++)
428 				for (i = 0; dcharmb[i] != '\0'; i++)
429 					putchar(dcharmb[i]);
430 			for (;;) {
431 				clen = mbrtowc(&ch, p, lbuf + reallen - p,
432 				    NULL);
433 				if (clen == (size_t)-1 || clen == (size_t)-2) {
434 					warnc(EILSEQ, "%s", fname);
435 					free(mlbuf);
436 					return (1);
437 				}
438 				if (clen == 0)
439 					clen = 1;
440 				p += clen;
441 				if (ch == '\n' || is_delim(ch)) {
442 					/* compress whitespace */
443 					if (wflag && ch != '\n')
444 						while (is_delim(*p))
445 							p++;
446 					break;
447 				}
448 				if (*pos)
449 					for (i = 0; i < (int)clen; i++)
450 						putchar(p[i - clen]);
451 			}
452 			if (ch == '\n')
453 				break;
454 		}
455 		if (ch != '\n') {
456 			if (autostop) {
457 				if (output)
458 					for (i = 0; dcharmb[i] != '\0'; i++)
459 						putchar(dcharmb[i]);
460 				for (; (ch = *p) != '\n'; ++p)
461 					(void)putchar(ch);
462 			} else
463 				for (; (ch = *p) != '\n'; ++p);
464 		}
465 		(void)putchar('\n');
466 	}
467 	free(mlbuf);
468 	return (0);
469 }
470 
471 static void
472 usage(void)
473 {
474 	(void)fprintf(stderr, "%s\n%s\n%s\n",
475 		"usage: cut -b list [-n] [file ...]",
476 		"       cut -c list [file ...]",
477 		"       cut -f list [-s] [-w | -d delim] [file ...]");
478 	exit(1);
479 }
480