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utils-std

Collection of commonly available Unix tools git clone https://anongit.hacktivis.me/git/utils-std.git/

cut.c (9152B)

    

  1. // utils-std: Collection of commonly available Unix tools
  2. // SPDX-FileCopyrightText: 2017 Haelwenn (lanodan) Monnier <contact+utils@hacktivis.me>
  3. // SPDX-License-Identifier: MPL-2.0
  5. #define _POSIX_C_SOURCE 202405L
  7. #include "../lib/reallocarray.h"
  8. #include "../libutils/getopt_nolong.h"
  10. #include <assert.h>
  11. #include <ctype.h>
  12. #include <errno.h>
  13. #include <locale.h>
  14. #include <stdbool.h>
  15. #include <stdint.h> // size_t
  16. #include <stdio.h>  // fprintf, fopen
  17. #include <string.h> // strerror
  18. #include <unistd.h> // getopt
  19. #include <wchar.h>
  21. #undef MIN
  22. #define MIN(a, b) (((a) < (b)) ? (a) : (b))
  24. enum cut_mode
  25. {
  26. 	CUT_MODE_NONE = 0,
  27. 	CUT_MODE_B = 1,
  28. 	CUT_MODE_C = 2,
  29. 	CUT_MODE_F = 3,
  30. };
  32. char delim = '\t';
  33. char line_delim = '\n';
  34. wchar_t line_delim_w = L'\n';
  35. bool opt_n = false, opt_s = false;
  36. enum cut_mode mode = CUT_MODE_NONE;
  37. bool *list = NULL;
  38. size_t list_len = 0;
  39. bool nostop = false;
  40. const char *argv0 = "cut";
  42. static size_t
  43. parse_list_num(char **s)
  44. {
  45. 	char *endptr = NULL;
  46. 	errno = 0;
  47. 	size_t n = strtoul(*s, &endptr, 10);
  48. 	if(errno != 0)
  49. 	{
  50. 		fprintf(stderr, "%s: error: Failed parsing '%s' as a number: %s\n", argv0, *s, strerror(errno));
  51. 		return 0;
  52. 	}
  54. 	if(n < 1)
  55. 	{
  56. 		fprintf(stderr, "%s: error: Invalid number in list: %zu\n", argv0, n);
  57. 		return 0;
  58. 	}
  60. 	if(endptr != NULL && strchr(",-", *endptr) == NULL)
  61. 	{
  62. 		fprintf(stderr, "%s: error: Invalid character in list: %c\n", argv0, *endptr);
  63. 		return 0;
  64. 	}
  66. 	*s = endptr;
  68. 	return n;
  69. }
  71. static int
  72. parse_list(char *s)
  73. {
  74. 	while(true)
  75. 	{
  76. 		if(s == NULL || *s == '\0') break;
  78. 		if(*s == ',')
  79. 		{
  80. 			fprintf(stderr, "%s: error: Empty list element\n", argv0);
  81. 			return -1;
  82. 		}
  84. 		size_t min = 1;
  85. 		if(*s != '-')
  86. 		{
  87. 			min = parse_list_num(&s);
  88. 			if(min == 0) return -1;
  89. 		}
  91. 		// min-- as cut(1) is 1-indexed and max needs to be at least min+1
  92. 		size_t max = min--;
  94. 		if(s && *s == '-')
  95. 		{
  96. 			s++;
  98. 			if(!isdigit(*s))
  99. 			{
  100. 				nostop = true;
  101. 			}
  102. 			else
  103. 			{
  104. 				max = parse_list_num(&s);
  105. 				if(max == 0) return -1;
  107. 				if(max < min)
  108. 				{
  109. 					fprintf(stderr, "%s: error: Decreasing range: %zu-%zu\n", argv0, min, max);
  110. 					return -1;
  111. 				}
  112. 			}
  113. 		}
  115. 		// Needs to be after *s == '-'
  116. 		if(s && *s == ',') s++;
  118. 		if(max > list_len)
  119. 		{
  120. 			list = reallocarray(list, max, sizeof(*list));
  121. 			if(list == NULL)
  122. 			{
  123. 				fprintf(stderr, "%s: error: Failed memory allocation: %s\n", argv0, strerror(errno));
  124. 				return -1;
  125. 			}
  127. 			if(min > list_len)
  128. 			{
  129. 				memset(list + list_len, 0, min - list_len);
  130. 			}
  132. 			list_len = max;
  133. 		}
  135. 		memset(list + min, 1, max - min);
  136. 	}
  138. 	if(list_len == 0)
  139. 	{
  140. 		fprintf(stderr, "%s: error: Empty list\n", argv0);
  141. 		return -1;
  142. 	}
  144. 	return 0;
  145. }
  147. static int
  148. cut_b(FILE *in, const char *filename)
  149. {
  150. 	char *line = NULL;
  151. 	size_t line_len = 0;
  152. 	int err = 0;
  154. 	while(err == 0)
  155. 	{
  156. 		errno = 0;
  157. 		ssize_t nread = getdelim(&line, &line_len, line_delim, in);
  159. 		if(nread < 0)
  160. 		{
  161. 			if(errno != 0)
  162. 			{
  163. 				fprintf(
  164. 				    stderr, "%s: error: Failed reading file '%s': %s\n", argv0, filename, strerror(errno));
  165. 				err = 1;
  166. 			}
  167. 			break;
  168. 		}
  170. 		if(nread == 0)
  171. 		{
  172. 			fputc(line_delim, stdout);
  173. 			continue;
  174. 		}
  176. 		if(line[nread - 1] == '\n') line[nread--] = '\0';
  178. 		for(size_t i = 0; i < MIN(list_len, (size_t)nread); i++)
  179. 			if(list[i]) fputc(line[i], stdout);
  181. 		if(nostop && (size_t)nread > list_len) fwrite(line + list_len, nread - list_len, 1, stdout);
  183. 		fputc(line_delim, stdout);
  184. 	}
  186. 	if(line_len != 0) free(line);
  188. 	return err;
  189. }
  191. static int
  192. cut_c(FILE *in, const char *filename)
  193. {
  194. 	char *line = NULL;
  195. 	size_t line_len = 0;
  196. 	int err = 0;
  197. 	wchar_t *line_w = NULL;
  198. 	ssize_t line_wsz = 0;
  200. 	while(err == 0)
  201. 	{
  202. 		errno = 0;
  203. 		ssize_t nread = getdelim(&line, &line_len, line_delim, in);
  205. 		if(nread < 0)
  206. 		{
  207. 			if(errno != 0)
  208. 			{
  209. 				fprintf(
  210. 				    stderr, "%s: error: Failed reading file '%s': %s\n", argv0, filename, strerror(errno));
  211. 				err = 1;
  212. 			}
  213. 			break;
  214. 		}
  216. 		if(nread == 0)
  217. 		{
  218. 			fputwc(line_delim_w, stdout);
  219. 			continue;
  220. 		}
  222. 		if(line[nread - 1] == '\n') line[nread--] = '\0';
  224. 		if(nread > line_wsz)
  225. 		{
  226. 			line_w = reallocarray(line_w, nread, sizeof(*line_w));
  227. 			if(line_w == NULL)
  228. 			{
  229. 				fprintf(stderr, "%s: error: Failed memory allocation: %s\n", argv0, strerror(errno));
  230. 				err = 1;
  231. 				break;
  232. 			}
  233. 			line_wsz = nread;
  234. 		}
  236. 		assert(line_wsz > 0);
  238. 		size_t wcread = mbstowcs(line_w, line, line_wsz);
  239. 		if(wcread == (size_t)-1)
  240. 		{
  241. 			fprintf(stderr,
  242. 			        "%s: error: Failed parsing characters in file '%s': %s\n",
  243. 			        argv0,
  244. 			        filename,
  245. 			        strerror(errno));
  246. 			err = 1;
  247. 			break;
  248. 		}
  250. 		//DEBUG fprintf(stderr, "cut: mbstowcs(_, _, %zu) => %zu\n", nread, wcread);
  252. 		size_t i = 0;
  253. 		for(; i < MIN(list_len, wcread); i++)
  254. 			if(list[i]) fputwc(line_w[i], stdout);
  256. 		if(nostop && wcread > list_len)
  257. 		{
  258. 			for(; i < wcread; i++)
  259. 				fputwc(line_w[i], stdout);
  260. 		}
  262. 		fputwc(line_delim_w, stdout);
  263. 	}
  265. 	free(line);
  266. 	free(line_w);
  268. 	return err;
  269. }
  271. static int
  272. cut_f(FILE *in, const char *filename)
  273. {
  274. 	char *line = NULL;
  275. 	size_t line_len = 0;
  276. 	int err = 0;
  278. 	while(err == 0)
  279. 	{
  280. 		errno = 0;
  281. 		ssize_t nread = getdelim(&line, &line_len, line_delim, in);
  283. 		if(nread < 0)
  284. 		{
  285. 			if(errno != 0)
  286. 			{
  287. 				fprintf(
  288. 				    stderr, "%s: error: Failed reading file '%s': %s\n", argv0, filename, strerror(errno));
  289. 				err = 1;
  290. 			}
  291. 			break;
  292. 		}
  294. 		if(nread == 0)
  295. 		{
  296. 			fputc(line_delim, stdout);
  297. 			continue;
  298. 		}
  300. 		if(line[nread - 1] == '\n') line[--nread] = '\0';
  302. 		size_t di = 0;
  303. 		for(; di < (size_t)nread; di++)
  304. 			if(line[di] == delim) break;
  306. 		if(di == (size_t)nread)
  307. 		{
  308. 			if(!opt_s) puts(line);
  310. 			continue;
  311. 		}
  313. 		bool need_sep = false;
  314. 		char *c = line;
  315. 		for(size_t pos = 0, i = 0; pos <= (size_t)nread; pos++)
  316. 		{
  317. 			if(pos < (size_t)nread && line[pos] != delim) continue;
  319. 			line[pos] = '\0';
  321. 			if(i >= list_len)
  322. 			{
  323. 				if(!nostop) break;
  325. 				if(need_sep) fputc(delim, stdout);
  327. 				fputs(c, stdout);
  328. 				need_sep = true;
  329. 			}
  330. 			else if(list[i])
  331. 			{
  332. 				if(need_sep) fputc(delim, stdout);
  334. 				fputs(c, stdout);
  335. 				need_sep = true;
  336. 			}
  338. 			i++;
  339. 			c = line + pos + 1;
  340. 		}
  342. 		fputc(line_delim, stdout);
  343. 	}
  345. 	if(line_len != 0) free(line);
  347. 	return err;
  348. }
  350. static int
  351. cut(FILE *in, const char *filename)
  352. {
  353. 	switch(mode)
  354. 	{
  355. 	case CUT_MODE_NONE:
  356. 		fprintf(stderr, "%s: error: No action (-b, -c, -f) specified\n", argv0);
  357. 		return 1;
  358. 	case CUT_MODE_B:
  359. 		return cut_b(in, filename);
  360. 	case CUT_MODE_C:
  361. 		return cut_c(in, filename);
  362. 	case CUT_MODE_F:
  363. 		return cut_f(in, filename);
  364. 	default:
  365. 		abort();
  366. 	}
  367. }
  369. int
  370. main(int argc, char *argv[])
  371. {
  372. 	char *opt_list = NULL;
  374. 	char *lc_all = setlocale(LC_ALL, "");
  375. 	if(lc_all == NULL)
  376. 	{
  377. 		fprintf(stderr,
  378. 		        "%s: warning: Failed loading locales. setlocale(LC_ALL, \"\"): %s\n",
  379. 		        argv0,
  380. 		        strerror(errno));
  381. 	}
  382. 	errno = 0;
  384. 	for(int c = -1; (c = getopt_nolong(argc, argv, ":b:c:d:f:nsz")) != -1;)
  385. 	{
  386. 		switch(c)
  387. 		{
  388. 		case 'b':
  389. 			if(opt_list != NULL)
  390. 			{
  391. 				fprintf(stderr, "%s: error: Only one list may be specified\n", argv0);
  392. 				return 1;
  393. 			}
  394. 			mode = CUT_MODE_B;
  395. 			opt_list = optarg;
  396. 			break;
  397. 		case 'c':
  398. 			if(opt_list != NULL)
  399. 			{
  400. 				fprintf(stderr, "%s: error: Only one list may be specified\n", argv0);
  401. 				return 1;
  402. 			}
  403. 			mode = CUT_MODE_C;
  404. 			opt_list = optarg;
  405. 			break;
  406. 		case 'f':
  407. 			if(opt_list != NULL)
  408. 			{
  409. 				fprintf(stderr, "%s: error: Only one list may be specified\n", argv0);
  410. 				return 1;
  411. 			}
  412. 			mode = CUT_MODE_F;
  413. 			opt_list = optarg;
  414. 			break;
  415. 		case 'd':
  416. 			if(optarg[0] != '\0' && optarg[1] != '\0')
  417. 			{
  418. 				fprintf(stderr,
  419. 				        "%s: error: Option '-d' only accepts single characters, got \"%s\"\n",
  420. 				        argv0,
  421. 				        optarg);
  422. 				return 1;
  423. 			}
  424. 			delim = optarg[0];
  425. 			break;
  426. 		case 'n':
  427. 			opt_n = true;
  428. 			break;
  429. 		case 's':
  430. 			opt_s = true;
  431. 			break;
  432. 		case 'z':
  433. 			line_delim = '\0';
  434. 			line_delim_w = L'\0';
  435. 			break;
  436. 		case ':':
  437. 			fprintf(stderr, "%s: error: Option '-%c' requires an operand\n", argv0, optopt);
  438. 			return 1;
  439. 		case '?':
  440. 			GETOPT_UNKNOWN_OPT
  441. 			return 1;
  442. 		default:
  443. 			fprintf(stderr, "%s: error: Unhandled getopt case '%c'\n", argv0, c);
  444. 			abort();
  445. 		}
  446. 	}
  448. 	argc -= optind;
  449. 	argv += optind;
  451. 	if(mode == CUT_MODE_NONE)
  452. 	{
  453. 		fprintf(stderr, "%s: error: No action (-b, -c, -f) specified\n", argv0);
  454. 		return 1;
  455. 	}
  457. 	if(parse_list(opt_list) < 0) return 1;
  459. #if 0
  460. 	fprintf(stderr, "[DEBUG] list: ");
  461. 	for(size_t i = 0; i < list_len; i++)
  462. 	{
  463. 		fputc(list[i] ? '1' : '0', stderr);
  464. 	}
  465. 	fputc('\n', stderr);
  466. #endif
  468. 	if(argc <= 0) return cut(stdin, "<stdin>");
  470. 	for(int i = 0; i < argc; i++)
  471. 	{
  472. 		FILE *in = fopen(argv[i], "r");
  473. 		if(in == NULL)
  474. 		{
  475. 			fprintf(stderr, "%s: error: Failed opening file '%s': %s\n", argv0, argv[i], strerror(errno));
  476. 			return 1;
  477. 		}
  479. 		int ret = cut(in, argv[i]);
  481. 		if(fclose(in) < 0)
  482. 		{
  483. 			fprintf(stderr, "%s: error: Failed closing file '%s': %s\n", argv0, argv[i], strerror(errno));
  484. 			return 1;
  485. 		}
  487. 		if(ret != 0) return 1;
  488. 	}
  490. 	if(fclose(stdin) != 0)
  491. 	{
  492. 		fprintf(stderr, "%s: error: Failed closing <stdin>: %s\n", argv0, strerror(errno));
  493. 		return 1;
  494. 	}
  496. 	if(fclose(stdout) != 0)
  497. 	{
  498. 		fprintf(stderr, "%s: error: Failed closing <stdout>: %s\n", argv0, strerror(errno));
  499. 		return 1;
  500. 	}
  502. 	return 0;
  503. }