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view code/cut.c__freebsd.2012-11-24 @ 25:aea7a19d400f

Schlusspointe: So muss das verstanden werden!

author	markus schnalke <meillo@marmaro.de>
date	Mon, 29 Jun 2015 21:37:01 +0200
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1 /*

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 */

33 #ifndef lint

34 static const char copyright[] =

37 static const char sccsid[] = "@(#)cut.c 8.3 (Berkeley) 5/4/95";

38 #endif /* not lint */

39 #include <sys/cdefs.h>

40 __FBSDID("$FreeBSD$");

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>

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;

63 static size_t autostart, autostop, maxval;

64 static char * positions;

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);

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;

83 setlocale(LC_ALL, "");

85 fcn = NULL;

86 dchar = '\t'; /* default delimiter is \t */

87 strcpy(dcharmb, "\t");

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 }