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utils-std

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

cut.c (8894B)

    

  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"
  9. #include <assert.h>
  10. #include <ctype.h>
  11. #include <errno.h>
  12. #include <locale.h>
  13. #include <stdbool.h>
  14. #include <stdint.h> // size_t
  15. #include <stdio.h>  // fprintf, fopen
  16. #include <string.h> // strerror
  17. #include <unistd.h> // getopt
  18. #include <wchar.h>
  20. #undef MIN
  21. #define MIN(a, b) (((a) < (b)) ? (a) : (b))
  23. enum cut_mode
  24. {
  25. 	CUT_MODE_NONE = 0,
  26. 	CUT_MODE_B = 1,
  27. 	CUT_MODE_C = 2,
  28. 	CUT_MODE_F = 3,
  29. };
  31. char delim = '\t';
  32. bool opt_n = false, opt_s = false;
  33. enum cut_mode mode = CUT_MODE_NONE;
  34. bool *list = NULL;
  35. size_t list_len = 0;
  36. bool nostop = false;
  37. const char *argv0 = "cut";
  39. static size_t
  40. parse_list_num(char **s)
  41. {
  42. 	char *endptr = NULL;
  43. 	errno = 0;
  44. 	size_t n = strtoul(*s, &endptr, 10);
  45. 	if(errno != 0)
  46. 	{
  47. 		fprintf(stderr, "%s: error: Failed parsing '%s' as a number: %s\n", argv0, *s, strerror(errno));
  48. 		return 0;
  49. 	}
  51. 	if(n < 1)
  52. 	{
  53. 		fprintf(stderr, "%s: error: Invalid number in list: %zu\n", argv0, n);
  54. 		return 0;
  55. 	}
  57. 	if(endptr != NULL && strchr(",-", *endptr) == NULL)
  58. 	{
  59. 		fprintf(stderr, "%s: error: Invalid character in list: %c\n", argv0, *endptr);
  60. 		return 0;
  61. 	}
  63. 	*s = endptr;
  65. 	return n;
  66. }
  68. static int
  69. parse_list(char *s)
  70. {
  71. 	while(true)
  72. 	{
  73. 		if(s == NULL || *s == '\0') break;
  75. 		if(*s == ',')
  76. 		{
  77. 			fprintf(stderr, "%s: error: Empty list element\n", argv0);
  78. 			return -1;
  79. 		}
  81. 		size_t min = 1;
  82. 		if(*s != '-')
  83. 		{
  84. 			min = parse_list_num(&s);
  85. 			if(min == 0) return -1;
  86. 		}
  88. 		// min-- as cut(1) is 1-indexed and max needs to be at least min+1
  89. 		size_t max = min--;
  91. 		if(s && *s == '-')
  92. 		{
  93. 			s++;
  95. 			if(!isdigit(*s))
  96. 			{
  97. 				nostop = true;
  98. 			}
  99. 			else
  100. 			{
  101. 				max = parse_list_num(&s);
  102. 				if(max == 0) return -1;
  104. 				if(max < min)
  105. 				{
  106. 					fprintf(stderr, "%s: error: Decreasing range: %zu-%zu\n", argv0, min, max);
  107. 					return -1;
  108. 				}
  109. 			}
  110. 		}
  112. 		// Needs to be after *s == '-'
  113. 		if(s && *s == ',') s++;
  115. 		if(max > list_len)
  116. 		{
  117. 			list = reallocarray(list, max, sizeof(*list));
  118. 			if(list == NULL)
  119. 			{
  120. 				fprintf(stderr, "%s: error: Failed memory allocation: %s\n", argv0, strerror(errno));
  121. 				return -1;
  122. 			}
  124. 			if(min > list_len)
  125. 			{
  126. 				memset(list + list_len, 0, min - list_len);
  127. 			}
  129. 			list_len = max;
  130. 		}
  132. 		memset(list + min, 1, max - min);
  133. 	}
  135. 	if(list_len == 0)
  136. 	{
  137. 		fprintf(stderr, "%s: error: Empty list\n", argv0);
  138. 		return -1;
  139. 	}
  141. 	return 0;
  142. }
  144. static int
  145. cut_b(FILE *in, const char *filename)
  146. {
  147. 	char *line = NULL;
  148. 	size_t line_len = 0;
  149. 	int err = 0;
  151. 	while(err == 0)
  152. 	{
  153. 		errno = 0;
  154. 		ssize_t nread = getline(&line, &line_len, in);
  156. 		if(nread < 0)
  157. 		{
  158. 			if(errno != 0)
  159. 			{
  160. 				fprintf(
  161. 				    stderr, "%s: error: Failed reading file '%s': %s\n", argv0, filename, strerror(errno));
  162. 				err = 1;
  163. 			}
  164. 			break;
  165. 		}
  167. 		if(nread == 0)
  168. 		{
  169. 			fputc('\n', stdout);
  170. 			continue;
  171. 		}
  173. 		if(line[nread - 1] == '\n') line[nread--] = '\0';
  175. 		for(size_t i = 0; i < MIN(list_len, (size_t)nread); i++)
  176. 			if(list[i]) fputc(line[i], stdout);
  178. 		if(nostop && (size_t)nread > list_len) fwrite(line + list_len, nread - list_len, 1, stdout);
  180. 		fputc('\n', stdout);
  181. 	}
  183. 	if(line_len != 0) free(line);
  185. 	return err;
  186. }
  188. static int
  189. cut_c(FILE *in, const char *filename)
  190. {
  191. 	char *line = NULL;
  192. 	size_t line_len = 0;
  193. 	int err = 0;
  194. 	wchar_t *line_w = NULL;
  195. 	ssize_t line_wsz = 0;
  197. 	while(err == 0)
  198. 	{
  199. 		errno = 0;
  200. 		ssize_t nread = getline(&line, &line_len, in);
  202. 		if(nread < 0)
  203. 		{
  204. 			if(errno != 0)
  205. 			{
  206. 				fprintf(
  207. 				    stderr, "%s: error: Failed reading file '%s': %s\n", argv0, filename, strerror(errno));
  208. 				err = 1;
  209. 			}
  210. 			break;
  211. 		}
  213. 		if(nread == 0)
  214. 		{
  215. 			fputc('\n', stdout);
  216. 			continue;
  217. 		}
  219. 		if(line[nread - 1] == '\n') line[nread--] = '\0';
  221. 		if(nread > line_wsz)
  222. 		{
  223. 			line_w = reallocarray(line_w, nread, sizeof(*line_w));
  224. 			if(line_w == NULL)
  225. 			{
  226. 				fprintf(stderr, "%s: error: Failed memory allocation: %s\n", argv0, strerror(errno));
  227. 				return -1;
  228. 			}
  229. 			line_wsz = nread;
  230. 		}
  232. 		assert(line_wsz > 0);
  234. 		size_t wcread = mbstowcs(line_w, line, line_wsz);
  235. 		if(wcread == (size_t)-1)
  236. 		{
  237. 			fprintf(stderr,
  238. 			        "%s: error: Failed parsing characters in file '%s': %s\n",
  239. 			        argv0,
  240. 			        filename,
  241. 			        strerror(errno));
  242. 			err = 1;
  243. 			break;
  244. 		}
  246. 		//DEBUG fprintf(stderr, "cut: mbstowcs(_, _, %zu) => %zu\n", nread, wcread);
  248. 		size_t i = 0;
  249. 		for(; i < MIN(list_len, wcread); i++)
  250. 			if(list[i]) fputwc(line_w[i], stdout);
  252. 		if(nostop && wcread > list_len)
  253. 		{
  254. 			for(; i < wcread; i++)
  255. 				fputwc(line_w[i], stdout);
  256. 		}
  258. 		fputc('\n', stdout);
  259. 	}
  261. 	if(line_len != 0) free(line);
  263. 	return err;
  264. }
  266. static int
  267. cut_f(FILE *in, const char *filename)
  268. {
  269. 	char *line = NULL;
  270. 	size_t line_len = 0;
  271. 	int err = 0;
  273. 	while(err == 0)
  274. 	{
  275. 		errno = 0;
  276. 		ssize_t nread = getline(&line, &line_len, in);
  278. 		if(nread < 0)
  279. 		{
  280. 			if(errno != 0)
  281. 			{
  282. 				fprintf(
  283. 				    stderr, "%s: error: Failed reading file '%s': %s\n", argv0, filename, strerror(errno));
  284. 				err = 1;
  285. 			}
  286. 			break;
  287. 		}
  289. 		if(nread == 0)
  290. 		{
  291. 			fputc('\n', stdout);
  292. 			continue;
  293. 		}
  295. 		if(line[nread - 1] == '\n') line[--nread] = '\0';
  297. 		size_t di = 0;
  298. 		for(; di < (size_t)nread; di++)
  299. 			if(line[di] == delim) break;
  301. 		if(di == (size_t)nread)
  302. 		{
  303. 			if(!opt_s) puts(line);
  305. 			continue;
  306. 		}
  308. 		bool need_sep = false;
  309. 		char *c = line;
  310. 		for(size_t pos = 0, i = 0; pos <= (size_t)nread; pos++)
  311. 		{
  312. 			if(pos < (size_t)nread && line[pos] != delim) continue;
  314. 			line[pos] = '\0';
  316. 			if(i >= list_len)
  317. 			{
  318. 				if(!nostop) break;
  320. 				if(need_sep) fputc(delim, stdout);
  322. 				fputs(c, stdout);
  323. 				need_sep = true;
  324. 			}
  325. 			else if(list[i])
  326. 			{
  327. 				if(need_sep) fputc(delim, stdout);
  329. 				fputs(c, stdout);
  330. 				need_sep = true;
  331. 			}
  333. 			i++;
  334. 			c = line + pos + 1;
  335. 		}
  337. 		fputc('\n', stdout);
  338. 	}
  340. 	if(line_len != 0) free(line);
  342. 	return err;
  343. }
  345. static int
  346. cut(FILE *in, const char *filename)
  347. {
  348. 	switch(mode)
  349. 	{
  350. 	case CUT_MODE_NONE:
  351. 		fprintf(stderr, "%s: error: No action (-b, -c, -f) specified\n", argv0);
  352. 		return 1;
  353. 	case CUT_MODE_B:
  354. 		return cut_b(in, filename);
  355. 	case CUT_MODE_C:
  356. 		return cut_c(in, filename);
  357. 	case CUT_MODE_F:
  358. 		return cut_f(in, filename);
  359. 	default:
  360. 		abort();
  361. 	}
  362. }
  364. int
  365. main(int argc, char *argv[])
  366. {
  367. 	char *opt_list = NULL;
  369. 	errno = 0;
  370. 	setlocale(LC_ALL, "");
  371. 	if(errno != 0)
  372. 	{
  373. 		fprintf(stderr, "%s: warning: Failed to initialize locales: %s\n", argv0, strerror(errno));
  374. 		errno = 0;
  375. 	}
  377. 	int c = -1;
  378. 	while((c = getopt(argc, argv, ":b:c:d:f:ns")) != -1)
  379. 	{
  380. 		switch(c)
  381. 		{
  382. 		case 'b':
  383. 			if(opt_list != NULL)
  384. 			{
  385. 				fprintf(stderr, "%s: error: Only one list may be specified\n", argv0);
  386. 				return 1;
  387. 			}
  388. 			mode = CUT_MODE_B;
  389. 			opt_list = optarg;
  390. 			break;
  391. 		case 'c':
  392. 			if(opt_list != NULL)
  393. 			{
  394. 				fprintf(stderr, "%s: error: Only one list may be specified\n", argv0);
  395. 				return 1;
  396. 			}
  397. 			mode = CUT_MODE_C;
  398. 			opt_list = optarg;
  399. 			break;
  400. 		case 'f':
  401. 			if(opt_list != NULL)
  402. 			{
  403. 				fprintf(stderr, "%s: error: Only one list may be specified\n", argv0);
  404. 				return 1;
  405. 			}
  406. 			mode = CUT_MODE_F;
  407. 			opt_list = optarg;
  408. 			break;
  409. 		case 'd':
  410. 			if(optarg[0] != '\0' && optarg[1] != '\0')
  411. 			{
  412. 				fprintf(stderr,
  413. 				        "%s: error: Option '-d' only accepts single characters, got \"%s\"\n",
  414. 				        argv0,
  415. 				        optarg);
  416. 				return 1;
  417. 			}
  418. 			delim = optarg[0];
  419. 			break;
  420. 		case 'n':
  421. 			opt_n = true;
  422. 			break;
  423. 		case 's':
  424. 			opt_s = true;
  425. 			break;
  426. 		case ':':
  427. 			fprintf(stderr, "%s: error: Option '-%c' requires an operand\n", argv0, optopt);
  428. 			return 1;
  429. 		case '?':
  430. 			fprintf(stderr, "%s: error: Unhandled option '-%c'\n", argv0, optopt);
  431. 			return 1;
  432. 		default:
  433. 			fprintf(stderr, "%s: error: Unhandled getopt case '%c'\n", argv0, c);
  434. 			abort();
  435. 		}
  436. 	}
  438. 	argc -= optind;
  439. 	argv += optind;
  441. 	if(mode == CUT_MODE_NONE)
  442. 	{
  443. 		fprintf(stderr, "%s: error: No action (-b, -c, -f) specified\n", argv0);
  444. 		return 1;
  445. 	}
  447. 	if(parse_list(opt_list) < 0) return 1;
  449. #if 0
  450. 	fprintf(stderr, "[DEBUG] list: ");
  451. 	for(size_t i = 0; i < list_len; i++)
  452. 	{
  453. 		fputc(list[i] ? '1' : '0', stderr);
  454. 	}
  455. 	fputc('\n', stderr);
  456. #endif
  458. 	if(argc <= 0) return cut(stdin, "<stdin>");
  460. 	for(int i = 0; i < argc; i++)
  461. 	{
  462. 		FILE *in = fopen(argv[i], "r");
  463. 		if(in == NULL)
  464. 		{
  465. 			fprintf(stderr, "%s: error: Failed opening file '%s': %s\n", argv0, argv[i], strerror(errno));
  466. 			return 1;
  467. 		}
  469. 		int ret = cut(in, argv[i]);
  471. 		if(fclose(in) < 0)
  472. 		{
  473. 			fprintf(stderr, "%s: error: Failed closing file '%s': %s\n", argv0, argv[i], strerror(errno));
  474. 			return 1;
  475. 		}
  477. 		if(ret != 0) return 1;
  478. 	}
  480. 	if(fclose(stdin) != 0)
  481. 	{
  482. 		fprintf(stderr, "%s: error: Failed closing <stdin>: %s\n", argv0, strerror(errno));
  483. 		return 1;
  484. 	}
  486. 	if(fclose(stdout) != 0)
  487. 	{
  488. 		fprintf(stderr, "%s: error: Failed closing <stdout>: %s\n", argv0, strerror(errno));
  489. 		return 1;
  490. 	}
  492. 	return 0;
  493. }