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Code ausgewaehlter Implementierungen eingefuegt Das Datum entspricht dem Dateiaenderungsdatum.
author markus schnalke <meillo@marmaro.de>
date Tue, 12 May 2015 06:46:59 +0200
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13:bf5e41260f89 14:21ad1c1548c4
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 }