cut.c revision 244297 
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
34static const char copyright[] =
35"@(#) Copyright (c) 1989, 1993\n\
36	The Regents of the University of California.  All rights reserved.\n";
37static const char sccsid[] = "@(#)cut.c	8.3 (Berkeley) 5/4/95";
38#endif /* not lint */
39#include <sys/cdefs.h>
40__FBSDID("$FreeBSD: stable/9/usr.bin/cut/cut.c 244297 2012-12-16 16:55:11Z eadler $");
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
53int	bflag;
54int	cflag;
55wchar_t	dchar;
56char	dcharmb[MB_LEN_MAX + 1];
57int	dflag;
58int	fflag;
59int	nflag;
60int	sflag;
61
62size_t	autostart, autostop, maxval;
63char *	positions;
64
65int	b_cut(FILE *, const char *);
66int	b_n_cut(FILE *, const char *);
67int	c_cut(FILE *, const char *);
68int	f_cut(FILE *, const char *);
69void	get_list(char *);
70void	needpos(size_t);
71static 	void usage(void);
72
73int
74main(int argc, char *argv[])
75{
76	FILE *fp;
77	int (*fcn)(FILE *, const char *);
78	int ch, rval;
79	size_t n;
80
81	setlocale(LC_ALL, "");
82
83	fcn = NULL;
84	dchar = '\t';			/* default delimiter is \t */
85	strcpy(dcharmb, "\t");
86
87	while ((ch = getopt(argc, argv, "b:c:d:f:sn")) != -1)
88		switch(ch) {
89		case 'b':
90			get_list(optarg);
91			bflag = 1;
92			break;
93		case 'c':
94			get_list(optarg);
95			cflag = 1;
96			break;
97		case 'd':
98			n = mbrtowc(&dchar, optarg, MB_LEN_MAX, NULL);
99			if (dchar == '\0' || n != strlen(optarg))
100				errx(1, "bad delimiter");
101			strcpy(dcharmb, optarg);
102			dflag = 1;
103			break;
104		case 'f':
105			get_list(optarg);
106			fflag = 1;
107			break;
108		case 's':
109			sflag = 1;
110			break;
111		case 'n':
112			nflag = 1;
113			break;
114		case '?':
115		default:
116			usage();
117		}
118	argc -= optind;
119	argv += optind;
120
121	if (fflag) {
122		if (bflag || cflag || nflag)
123			usage();
124	} else if (!(bflag || cflag) || dflag || sflag)
125		usage();
126	else if (!bflag && nflag)
127		usage();
128
129	if (fflag)
130		fcn = f_cut;
131	else if (cflag)
132		fcn = MB_CUR_MAX > 1 ? c_cut : b_cut;
133	else if (bflag)
134		fcn = nflag && MB_CUR_MAX > 1 ? b_n_cut : b_cut;
135
136	rval = 0;
137	if (*argv)
138		for (; *argv; ++argv) {
139			if (strcmp(*argv, "-") == 0)
140				rval |= fcn(stdin, "stdin");
141			else {
142				if (!(fp = fopen(*argv, "r"))) {
143					warn("%s", *argv);
144					rval = 1;
145					continue;
146				}
147				fcn(fp, *argv);
148				(void)fclose(fp);
149			}
150		}
151	else
152		rval = fcn(stdin, "stdin");
153	exit(rval);
154}
155
156void
157get_list(char *list)
158{
159	size_t setautostart, start, stop;
160	char *pos;
161	char *p;
162
163	/*
164	 * set a byte in the positions array to indicate if a field or
165	 * column is to be selected; use +1, it's 1-based, not 0-based.
166	 * Numbers and number ranges may be overlapping, repeated, and in
167	 * any order. We handle "-3-5" although there's no real reason to.
168	 */
169	for (; (p = strsep(&list, ", \t")) != NULL;) {
170		setautostart = start = stop = 0;
171		if (*p == '-') {
172			++p;
173			setautostart = 1;
174		}
175		if (isdigit((unsigned char)*p)) {
176			start = stop = strtol(p, &p, 10);
177			if (setautostart && start > autostart)
178				autostart = start;
179		}
180		if (*p == '-') {
181			if (isdigit((unsigned char)p[1]))
182				stop = strtol(p + 1, &p, 10);
183			if (*p == '-') {
184				++p;
185				if (!autostop || autostop > stop)
186					autostop = stop;
187			}
188		}
189		if (*p)
190			errx(1, "[-bcf] list: illegal list value");
191		if (!stop || !start)
192			errx(1, "[-bcf] list: values may not include zero");
193		if (maxval < stop) {
194			maxval = stop;
195			needpos(maxval + 1);
196		}
197		for (pos = positions + start; start++ <= stop; *pos++ = 1);
198	}
199
200	/* overlapping ranges */
201	if (autostop && maxval > autostop) {
202		maxval = autostop;
203		needpos(maxval + 1);
204	}
205
206	/* set autostart */
207	if (autostart)
208		memset(positions + 1, '1', autostart);
209}
210
211void
212needpos(size_t n)
213{
214	static size_t npos;
215	size_t oldnpos;
216
217	/* Grow the positions array to at least the specified size. */
218	if (n > npos) {
219		oldnpos = npos;
220		if (npos == 0)
221			npos = n;
222		while (n > npos)
223			npos *= 2;
224		if ((positions = realloc(positions, npos)) == NULL)
225			err(1, "realloc");
226		memset((char *)positions + oldnpos, 0, npos - oldnpos);
227	}
228}
229
230int
231b_cut(FILE *fp, const char *fname __unused)
232{
233	int ch, col;
234	char *pos;
235
236	ch = 0;
237	for (;;) {
238		pos = positions + 1;
239		for (col = maxval; col; --col) {
240			if ((ch = getc(fp)) == EOF)
241				return (0);
242			if (ch == '\n')
243				break;
244			if (*pos++)
245				(void)putchar(ch);
246		}
247		if (ch != '\n') {
248			if (autostop)
249				while ((ch = getc(fp)) != EOF && ch != '\n')
250					(void)putchar(ch);
251			else
252				while ((ch = getc(fp)) != EOF && ch != '\n');
253		}
254		(void)putchar('\n');
255	}
256	return (0);
257}
258
259/*
260 * Cut based on byte positions, taking care not to split multibyte characters.
261 * Although this function also handles the case where -n is not specified,
262 * b_cut() ought to be much faster.
263 */
264int
265b_n_cut(FILE *fp, const char *fname)
266{
267	size_t col, i, lbuflen;
268	char *lbuf;
269	int canwrite, clen, warned;
270	mbstate_t mbs;
271
272	memset(&mbs, 0, sizeof(mbs));
273	warned = 0;
274	while ((lbuf = fgetln(fp, &lbuflen)) != NULL) {
275		for (col = 0; lbuflen > 0; col += clen) {
276			if ((clen = mbrlen(lbuf, lbuflen, &mbs)) < 0) {
277				if (!warned) {
278					warn("%s", fname);
279					warned = 1;
280				}
281				memset(&mbs, 0, sizeof(mbs));
282				clen = 1;
283			}
284			if (clen == 0 || *lbuf == '\n')
285				break;
286			if (col < maxval && !positions[1 + col]) {
287				/*
288				 * Print the character if (1) after an initial
289				 * segment of un-selected bytes, the rest of
290				 * it is selected, and (2) the last byte is
291				 * selected.
292				 */
293				i = col;
294				while (i < col + clen && i < maxval &&
295				    !positions[1 + i])
296					i++;
297				canwrite = i < col + clen;
298				for (; i < col + clen && i < maxval; i++)
299					canwrite &= positions[1 + i];
300				if (canwrite)
301					fwrite(lbuf, 1, clen, stdout);
302			} else {
303				/*
304				 * Print the character if all of it has
305				 * been selected.
306				 */
307				canwrite = 1;
308				for (i = col; i < col + clen; i++)
309					if ((i >= maxval && !autostop) ||
310					    (i < maxval && !positions[1 + i])) {
311						canwrite = 0;
312						break;
313					}
314				if (canwrite)
315					fwrite(lbuf, 1, clen, stdout);
316			}
317			lbuf += clen;
318			lbuflen -= clen;
319		}
320		if (lbuflen > 0)
321			putchar('\n');
322	}
323	return (warned);
324}
325
326int
327c_cut(FILE *fp, const char *fname)
328{
329	wint_t ch;
330	int col;
331	char *pos;
332
333	ch = 0;
334	for (;;) {
335		pos = positions + 1;
336		for (col = maxval; col; --col) {
337			if ((ch = getwc(fp)) == WEOF)
338				goto out;
339			if (ch == '\n')
340				break;
341			if (*pos++)
342				(void)putwchar(ch);
343		}
344		if (ch != '\n') {
345			if (autostop)
346				while ((ch = getwc(fp)) != WEOF && ch != '\n')
347					(void)putwchar(ch);
348			else
349				while ((ch = getwc(fp)) != WEOF && ch != '\n');
350		}
351		(void)putwchar('\n');
352	}
353out:
354	if (ferror(fp)) {
355		warn("%s", fname);
356		return (1);
357	}
358	return (0);
359}
360
361int
362f_cut(FILE *fp, const char *fname)
363{
364	wchar_t ch;
365	int field, i, isdelim;
366	char *pos, *p;
367	wchar_t sep;
368	int output;
369	char *lbuf, *mlbuf;
370	size_t clen, lbuflen, reallen;
371
372	mlbuf = NULL;
373	for (sep = dchar; (lbuf = fgetln(fp, &lbuflen)) != NULL;) {
374		reallen = lbuflen;
375		/* Assert EOL has a newline. */
376		if (*(lbuf + lbuflen - 1) != '\n') {
377			/* Can't have > 1 line with no trailing newline. */
378			mlbuf = malloc(lbuflen + 1);
379			if (mlbuf == NULL)
380				err(1, "malloc");
381			memcpy(mlbuf, lbuf, lbuflen);
382			*(mlbuf + lbuflen) = '\n';
383			lbuf = mlbuf;
384			reallen++;
385		}
386		output = 0;
387		for (isdelim = 0, p = lbuf;; p += clen) {
388			clen = mbrtowc(&ch, p, lbuf + reallen - p, NULL);
389			if (clen == (size_t)-1 || clen == (size_t)-2) {
390				warnc(EILSEQ, "%s", fname);
391				free(mlbuf);
392				return (1);
393			}
394			if (clen == 0)
395				clen = 1;
396			/* this should work if newline is delimiter */
397			if (ch == sep)
398				isdelim = 1;
399			if (ch == '\n') {
400				if (!isdelim && !sflag)
401					(void)fwrite(lbuf, lbuflen, 1, stdout);
402				break;
403			}
404		}
405		if (!isdelim)
406			continue;
407
408		pos = positions + 1;
409		for (field = maxval, p = lbuf; field; --field, ++pos) {
410			if (*pos && output++)
411				for (i = 0; dcharmb[i] != '\0'; i++)
412					putchar(dcharmb[i]);
413			for (;;) {
414				clen = mbrtowc(&ch, p, lbuf + reallen - p,
415				    NULL);
416				if (clen == (size_t)-1 || clen == (size_t)-2) {
417					warnc(EILSEQ, "%s", fname);
418					free(mlbuf);
419					return (1);
420				}
421				if (clen == 0)
422					clen = 1;
423				p += clen;
424				if (ch == '\n' || ch == sep)
425					break;
426				if (*pos)
427					for (i = 0; i < (int)clen; i++)
428						putchar(p[i - clen]);
429			}
430			if (ch == '\n')
431				break;
432		}
433		if (ch != '\n') {
434			if (autostop) {
435				if (output)
436					for (i = 0; dcharmb[i] != '\0'; i++)
437						putchar(dcharmb[i]);
438				for (; (ch = *p) != '\n'; ++p)
439					(void)putchar(ch);
440			} else
441				for (; (ch = *p) != '\n'; ++p);
442		}
443		(void)putchar('\n');
444	}
445	free(mlbuf);
446	return (0);
447}
448
449static void
450usage(void)
451{
452	(void)fprintf(stderr, "%s\n%s\n%s\n",
453		"usage: cut -b list [-n] [file ...]",
454		"       cut -c list [file ...]",
455		"       cut -f list [-s] [-d delim] [file ...]");
456	exit(1);
457}
458