cut.c revision 131183 
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 * 3. All advertising materials mentioning features or use of this software
17 *    must display the following acknowledgement:
18 *	This product includes software developed by the University of
19 *	California, Berkeley and its contributors.
20 * 4. Neither the name of the University nor the names of its contributors
21 *    may be used to endorse or promote products derived from this software
22 *    without specific prior written permission.
23 *
24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34 * SUCH DAMAGE.
35 */
36
37#ifndef lint
38static const char copyright[] =
39"@(#) Copyright (c) 1989, 1993\n\
40	The Regents of the University of California.  All rights reserved.\n";
41static const char sccsid[] = "@(#)cut.c	8.3 (Berkeley) 5/4/95";
42#endif /* not lint */
43#include <sys/cdefs.h>
44__FBSDID("$FreeBSD: head/usr.bin/cut/cut.c 131183 2004-06-27 10:35:28Z tjr $");
45
46#include <ctype.h>
47#include <err.h>
48#include <limits.h>
49#include <locale.h>
50#include <stdio.h>
51#include <stdlib.h>
52#include <string.h>
53#include <unistd.h>
54#include <wchar.h>
55
56int	bflag;
57int	cflag;
58char	dchar;
59int	dflag;
60int	fflag;
61int	nflag;
62int	sflag;
63
64void	b_n_cut(FILE *, const char *);
65void	c_cut(FILE *, const char *);
66void	f_cut(FILE *, const char *);
67void	get_list(char *);
68void	needpos(size_t);
69static 	void usage(void);
70
71int
72main(int argc, char *argv[])
73{
74	FILE *fp;
75	void (*fcn)(FILE *, const char *);
76	int ch, rval;
77
78	setlocale(LC_ALL, "");
79
80	fcn = NULL;
81	dchar = '\t';			/* default delimiter is \t */
82
83	/*
84	 * Since we don't support multi-byte characters, the -c and -b
85	 * options are equivalent.
86	 */
87	while ((ch = getopt(argc, argv, "b:c:d:f:sn")) != -1)
88		switch(ch) {
89		case 'b':
90			fcn = c_cut;
91			get_list(optarg);
92			bflag = 1;
93			break;
94		case 'c':
95			fcn = c_cut;
96			get_list(optarg);
97			cflag = 1;
98			break;
99		case 'd':
100			dchar = *optarg;
101			dflag = 1;
102			break;
103		case 'f':
104			get_list(optarg);
105			fcn = f_cut;
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 (nflag)
130		fcn = b_n_cut;
131
132	rval = 0;
133	if (*argv)
134		for (; *argv; ++argv) {
135			if (strcmp(*argv, "-") == 0)
136				fcn(stdin, "stdin");
137			else {
138				if (!(fp = fopen(*argv, "r"))) {
139					warn("%s", *argv);
140					rval = 1;
141					continue;
142				}
143				fcn(fp, *argv);
144				(void)fclose(fp);
145			}
146		}
147	else
148		fcn(stdin, "stdin");
149	exit(rval);
150}
151
152size_t autostart, autostop, maxval;
153
154char *positions;
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	 * This parser is less restrictive than the Draft 9 POSIX spec.
167	 * POSIX doesn't allow lists that aren't in increasing order or
168	 * overlapping lists.  We also handle "-3-5" although there's no
169	 * real reason too.
170	 */
171	for (; (p = strsep(&list, ", \t")) != NULL;) {
172		setautostart = start = stop = 0;
173		if (*p == '-') {
174			++p;
175			setautostart = 1;
176		}
177		if (isdigit((unsigned char)*p)) {
178			start = stop = strtol(p, &p, 10);
179			if (setautostart && start > autostart)
180				autostart = start;
181		}
182		if (*p == '-') {
183			if (isdigit((unsigned char)p[1]))
184				stop = strtol(p + 1, &p, 10);
185			if (*p == '-') {
186				++p;
187				if (!autostop || autostop > stop)
188					autostop = stop;
189			}
190		}
191		if (*p)
192			errx(1, "[-cf] list: illegal list value");
193		if (!stop || !start)
194			errx(1, "[-cf] list: values may not include zero");
195		if (maxval < stop) {
196			maxval = stop;
197			needpos(maxval + 1);
198		}
199		for (pos = positions + start; start++ <= stop; *pos++ = 1);
200	}
201
202	/* overlapping ranges */
203	if (autostop && maxval > autostop) {
204		maxval = autostop;
205		needpos(maxval + 1);
206	}
207
208	/* set autostart */
209	if (autostart)
210		memset(positions + 1, '1', autostart);
211}
212
213void
214needpos(size_t n)
215{
216	static size_t npos;
217	size_t oldnpos;
218
219	/* Grow the positions array to at least the specified size. */
220	if (n > npos) {
221		oldnpos = npos;
222		if (npos == 0)
223			npos = n;
224		while (n > npos)
225			npos *= 2;
226		if ((positions = realloc(positions, npos)) == NULL)
227			err(1, "realloc");
228		memset((char *)positions + oldnpos, 0, npos - oldnpos);
229	}
230}
231
232/*
233 * Cut based on byte positions, taking care not to split multibyte characters.
234 * Although this function also handles the case where -n is not specified,
235 * c_cut() ought to be much faster.
236 */
237void
238b_n_cut(FILE *fp, const char *fname)
239{
240	size_t col, i, lbuflen;
241	char *lbuf;
242	int canwrite, clen, warned;
243	mbstate_t mbs;
244
245	memset(&mbs, 0, sizeof(mbs));
246	warned = 0;
247	while ((lbuf = fgetln(fp, &lbuflen)) != NULL) {
248		for (col = 0; lbuflen > 0; col += clen) {
249			if ((clen = mbrlen(lbuf, lbuflen, &mbs)) < 0) {
250				if (!warned) {
251					warn("%s", fname);
252					warned = 1;
253				}
254				memset(&mbs, 0, sizeof(mbs));
255				clen = 1;
256			}
257			if (clen == 0 || *lbuf == '\n')
258				break;
259			if (col < maxval && !positions[1 + col]) {
260				/*
261				 * Print the character if (1) after an initial
262				 * segment of un-selected bytes, the rest of
263				 * it is selected, and (2) the last byte is
264				 * selected.
265				 */
266				i = col;
267				while (i < col + clen && i < maxval &&
268				    !positions[1 + i])
269					i++;
270				canwrite = i < col + clen;
271				for (; i < col + clen && i < maxval; i++)
272					canwrite &= positions[1 + i];
273				if (canwrite)
274					fwrite(lbuf, 1, clen, stdout);
275			} else {
276				/*
277				 * Print the character if all of it has
278				 * been selected.
279				 */
280				canwrite = 1;
281				for (i = col; i < col + clen; i++)
282					if ((i >= maxval && !autostop) ||
283					    (i < maxval && !positions[1 + i])) {
284						canwrite = 0;
285						break;
286					}
287				if (canwrite)
288					fwrite(lbuf, 1, clen, stdout);
289			}
290			lbuf += clen;
291			lbuflen -= clen;
292		}
293		if (lbuflen > 0)
294			putchar('\n');
295	}
296}
297
298void
299c_cut(FILE *fp, const char *fname __unused)
300{
301	int ch, col;
302	char *pos;
303
304	ch = 0;
305	for (;;) {
306		pos = positions + 1;
307		for (col = maxval; col; --col) {
308			if ((ch = getc(fp)) == EOF)
309				return;
310			if (ch == '\n')
311				break;
312			if (*pos++)
313				(void)putchar(ch);
314		}
315		if (ch != '\n') {
316			if (autostop)
317				while ((ch = getc(fp)) != EOF && ch != '\n')
318					(void)putchar(ch);
319			else
320				while ((ch = getc(fp)) != EOF && ch != '\n');
321		}
322		(void)putchar('\n');
323	}
324}
325
326void
327f_cut(FILE *fp, const char *fname __unused)
328{
329	int ch, field, isdelim;
330	char *pos, *p, sep;
331	int output;
332	char *lbuf, *mlbuf;
333	size_t lbuflen;
334
335	mlbuf = NULL;
336	for (sep = dchar; (lbuf = fgetln(fp, &lbuflen)) != NULL;) {
337		/* Assert EOL has a newline. */
338		if (*(lbuf + lbuflen - 1) != '\n') {
339			/* Can't have > 1 line with no trailing newline. */
340			mlbuf = malloc(lbuflen + 1);
341			if (mlbuf == NULL)
342				err(1, "malloc");
343			memcpy(mlbuf, lbuf, lbuflen);
344			*(mlbuf + lbuflen) = '\n';
345			lbuf = mlbuf;
346		}
347		output = 0;
348		for (isdelim = 0, p = lbuf;; ++p) {
349			ch = *p;
350			/* this should work if newline is delimiter */
351			if (ch == sep)
352				isdelim = 1;
353			if (ch == '\n') {
354				if (!isdelim && !sflag)
355					(void)fwrite(lbuf, lbuflen, 1, stdout);
356				break;
357			}
358		}
359		if (!isdelim)
360			continue;
361
362		pos = positions + 1;
363		for (field = maxval, p = lbuf; field; --field, ++pos) {
364			if (*pos) {
365				if (output++)
366					(void)putchar(sep);
367				while ((ch = *p++) != '\n' && ch != sep)
368					(void)putchar(ch);
369			} else {
370				while ((ch = *p++) != '\n' && ch != sep)
371					continue;
372			}
373			if (ch == '\n')
374				break;
375		}
376		if (ch != '\n') {
377			if (autostop) {
378				if (output)
379					(void)putchar(sep);
380				for (; (ch = *p) != '\n'; ++p)
381					(void)putchar(ch);
382			} else
383				for (; (ch = *p) != '\n'; ++p);
384		}
385		(void)putchar('\n');
386	}
387	if (mlbuf != NULL)
388		free(mlbuf);
389}
390
391static void
392usage(void)
393{
394	(void)fprintf(stderr, "%s\n%s\n%s\n",
395		"usage: cut -b list [-n] [file ...]",
396		"       cut -c list [file ...]",
397		"       cut -f list [-s] [-d delim] [file ...]");
398	exit(1);
399}
400