logo

utils-std

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

cut.c (9842B)

    

  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 "../config.h"
  8. #include "../lib/reallocarray.h"
  9. #include "../libutils/getopt_nolong.h"
  11. #include <assert.h>
  12. #include <ctype.h>
  13. #include <errno.h>
  14. #include <locale.h>
  15. #include <stdbool.h>
  16. #include <stdint.h> // size_t
  17. #include <stdio.h>  // fprintf, fopen
  18. #include <string.h> // strerror
  19. #include <unistd.h> // getopt
  20. #include <wchar.h>
  21. #ifdef HAS_GETOPT_LONG
  22. #include <getopt.h>
  23. #endif
  25. #undef MIN
  26. #define MIN(a, b) (((a) < (b)) ? (a) : (b))
  28. enum cut_mode
  29. {
  30. 	CUT_MODE_NONE = 0,
  31. 	CUT_MODE_B = 1,
  32. 	CUT_MODE_C = 2,
  33. 	CUT_MODE_F = 3,
  34. };
  36. char delim = '\t';
  37. char line_delim = '\n';
  38. wchar_t line_delim_w = L'\n';
  39. bool opt_n = false, opt_s = false;
  40. enum cut_mode mode = CUT_MODE_NONE;
  41. bool *list = NULL;
  42. size_t list_len = 0;
  43. bool nostop = false;
  44. const char *argv0 = "cut";
  46. static size_t
  47. parse_list_num(char **s)
  48. {
  49. 	char *endptr = NULL;
  50. 	errno = 0;
  51. 	size_t n = strtoul(*s, &endptr, 10);
  52. 	if(errno != 0)
  53. 	{
  54. 		fprintf(stderr, "%s: error: Failed parsing '%s' as a number: %s\n", argv0, *s, strerror(errno));
  55. 		return 0;
  56. 	}
  58. 	if(n < 1)
  59. 	{
  60. 		fprintf(stderr, "%s: error: Invalid number in list: %zu\n", argv0, n);
  61. 		return 0;
  62. 	}
  64. 	if(endptr != NULL && strchr(",-", *endptr) == NULL)
  65. 	{
  66. 		fprintf(stderr, "%s: error: Invalid character in list: %c\n", argv0, *endptr);
  67. 		return 0;
  68. 	}
  70. 	*s = endptr;
  72. 	return n;
  73. }
  75. static int
  76. parse_list(char *s)
  77. {
  78. 	while(true)
  79. 	{
  80. 		if(s == NULL || *s == '\0') break;
  82. 		if(*s == ',')
  83. 		{
  84. 			fprintf(stderr, "%s: error: Empty list element\n", argv0);
  85. 			return -1;
  86. 		}
  88. 		size_t min = 1;
  89. 		if(*s != '-')
  90. 		{
  91. 			min = parse_list_num(&s);
  92. 			if(min == 0) return -1;
  93. 		}
  95. 		// min-- as cut(1) is 1-indexed and max needs to be at least min+1
  96. 		size_t max = min--;
  98. 		if(s && *s == '-')
  99. 		{
  100. 			s++;
  102. 			if(!isdigit(*s))
  103. 			{
  104. 				nostop = true;
  105. 			}
  106. 			else
  107. 			{
  108. 				max = parse_list_num(&s);
  109. 				if(max == 0) return -1;
  111. 				if(max < min)
  112. 				{
  113. 					fprintf(stderr, "%s: error: Decreasing range: %zu-%zu\n", argv0, min, max);
  114. 					return -1;
  115. 				}
  116. 			}
  117. 		}
  119. 		// Needs to be after *s == '-'
  120. 		if(s && *s == ',') s++;
  122. 		if(max > list_len)
  123. 		{
  124. 			list = reallocarray(list, max, sizeof(*list));
  125. 			if(list == NULL)
  126. 			{
  127. 				fprintf(stderr, "%s: error: Failed memory allocation: %s\n", argv0, strerror(errno));
  128. 				return -1;
  129. 			}
  131. 			if(min > list_len)
  132. 			{
  133. 				memset(list + list_len, 0, min - list_len);
  134. 			}
  136. 			list_len = max;
  137. 		}
  139. 		memset(list + min, 1, max - min);
  140. 	}
  142. 	if(list_len == 0)
  143. 	{
  144. 		fprintf(stderr, "%s: error: Empty list\n", argv0);
  145. 		return -1;
  146. 	}
  148. 	return 0;
  149. }
  151. static int
  152. cut_b(FILE *in, const char *filename)
  153. {
  154. 	char *line = NULL;
  155. 	size_t line_len = 0;
  156. 	int err = 0;
  158. 	while(err == 0)
  159. 	{
  160. 		errno = 0;
  161. 		ssize_t nread = getdelim(&line, &line_len, line_delim, in);
  163. 		if(nread < 0)
  164. 		{
  165. 			if(errno != 0)
  166. 			{
  167. 				fprintf(
  168. 				    stderr, "%s: error: Failed reading file '%s': %s\n", argv0, filename, strerror(errno));
  169. 				err = 1;
  170. 			}
  171. 			break;
  172. 		}
  174. 		if(nread == 0)
  175. 		{
  176. 			fputc(line_delim, stdout);
  177. 			continue;
  178. 		}
  180. 		if(line[nread - 1] == '\n') line[nread--] = '\0';
  182. 		for(size_t i = 0; i < MIN(list_len, (size_t)nread); i++)
  183. 			if(list[i]) fputc(line[i], stdout);
  185. 		if(nostop && (size_t)nread > list_len) fwrite(line + list_len, nread - list_len, 1, stdout);
  187. 		fputc(line_delim, stdout);
  188. 	}
  190. 	if(line_len != 0) free(line);
  192. 	return err;
  193. }
  195. static int
  196. cut_c(FILE *in, const char *filename)
  197. {
  198. 	char *line = NULL;
  199. 	size_t line_len = 0;
  200. 	int err = 0;
  201. 	wchar_t *line_w = NULL;
  202. 	ssize_t line_wsz = 0;
  204. 	while(err == 0)
  205. 	{
  206. 		errno = 0;
  207. 		ssize_t nread = getdelim(&line, &line_len, line_delim, in);
  209. 		if(nread < 0)
  210. 		{
  211. 			if(errno != 0)
  212. 			{
  213. 				fprintf(
  214. 				    stderr, "%s: error: Failed reading file '%s': %s\n", argv0, filename, strerror(errno));
  215. 				err = 1;
  216. 			}
  217. 			break;
  218. 		}
  220. 		if(nread == 0)
  221. 		{
  222. 			fputwc(line_delim_w, stdout);
  223. 			continue;
  224. 		}
  226. 		if(line[nread - 1] == '\n') line[nread--] = '\0';
  228. 		if(nread > line_wsz)
  229. 		{
  230. 			line_w = reallocarray(line_w, nread, sizeof(*line_w));
  231. 			if(line_w == NULL)
  232. 			{
  233. 				fprintf(stderr, "%s: error: Failed memory allocation: %s\n", argv0, strerror(errno));
  234. 				err = 1;
  235. 				break;
  236. 			}
  237. 			line_wsz = nread;
  238. 		}
  240. 		assert(line_wsz > 0);
  242. 		size_t wcread = mbstowcs(line_w, line, line_wsz);
  243. 		if(wcread == (size_t)-1)
  244. 		{
  245. 			fprintf(stderr,
  246. 			        "%s: error: Failed parsing characters in file '%s': %s\n",
  247. 			        argv0,
  248. 			        filename,
  249. 			        strerror(errno));
  250. 			err = 1;
  251. 			break;
  252. 		}
  254. 		//DEBUG fprintf(stderr, "cut: mbstowcs(_, _, %zu) => %zu\n", nread, wcread);
  256. 		size_t i = 0;
  257. 		for(; i < MIN(list_len, wcread); i++)
  258. 			if(list[i]) fputwc(line_w[i], stdout);
  260. 		if(nostop && wcread > list_len)
  261. 		{
  262. 			for(; i < wcread; i++)
  263. 				fputwc(line_w[i], stdout);
  264. 		}
  266. 		fputwc(line_delim_w, stdout);
  267. 	}
  269. 	free(line);
  270. 	free(line_w);
  272. 	return err;
  273. }
  275. static int
  276. cut_f(FILE *in, const char *filename)
  277. {
  278. 	char *line = NULL;
  279. 	size_t line_len = 0;
  280. 	int err = 0;
  282. 	while(err == 0)
  283. 	{
  284. 		errno = 0;
  285. 		ssize_t nread = getdelim(&line, &line_len, line_delim, in);
  287. 		if(nread < 0)
  288. 		{
  289. 			if(errno != 0)
  290. 			{
  291. 				fprintf(
  292. 				    stderr, "%s: error: Failed reading file '%s': %s\n", argv0, filename, strerror(errno));
  293. 				err = 1;
  294. 			}
  295. 			break;
  296. 		}
  298. 		if(nread == 0)
  299. 		{
  300. 			fputc(line_delim, stdout);
  301. 			continue;
  302. 		}
  304. 		if(line[nread - 1] == '\n') line[--nread] = '\0';
  306. 		size_t di = 0;
  307. 		for(; di < (size_t)nread; di++)
  308. 			if(line[di] == delim) break;
  310. 		if(di == (size_t)nread)
  311. 		{
  312. 			if(!opt_s) puts(line);
  314. 			continue;
  315. 		}
  317. 		bool need_sep = false;
  318. 		char *c = line;
  319. 		for(size_t pos = 0, i = 0; pos <= (size_t)nread; pos++)
  320. 		{
  321. 			if(pos < (size_t)nread && line[pos] != delim) continue;
  323. 			line[pos] = '\0';
  325. 			if(i >= list_len)
  326. 			{
  327. 				if(!nostop) break;
  329. 				if(need_sep) fputc(delim, stdout);
  331. 				fputs(c, stdout);
  332. 				need_sep = true;
  333. 			}
  334. 			else if(list[i])
  335. 			{
  336. 				if(need_sep) fputc(delim, stdout);
  338. 				fputs(c, stdout);
  339. 				need_sep = true;
  340. 			}
  342. 			i++;
  343. 			c = line + pos + 1;
  344. 		}
  346. 		fputc(line_delim, stdout);
  347. 	}
  349. 	if(line_len != 0) free(line);
  351. 	return err;
  352. }
  354. static int
  355. cut(FILE *in, const char *filename)
  356. {
  357. 	switch(mode)
  358. 	{
  359. 	case CUT_MODE_NONE:
  360. 		fprintf(stderr, "%s: error: No action (-b, -c, -f) specified\n", argv0);
  361. 		return 1;
  362. 	case CUT_MODE_B:
  363. 		return cut_b(in, filename);
  364. 	case CUT_MODE_C:
  365. 		return cut_c(in, filename);
  366. 	case CUT_MODE_F:
  367. 		return cut_f(in, filename);
  368. 	default:
  369. 		abort();
  370. 	}
  371. }
  373. int
  374. main(int argc, char *argv[])
  375. {
  376. 	char *opt_list = NULL;
  378. 	char *lc_all = setlocale(LC_ALL, "");
  379. 	if(lc_all == NULL)
  380. 	{
  381. 		fprintf(stderr,
  382. 		        "%s: warning: Failed loading locales. setlocale(LC_ALL, \"\"): %s\n",
  383. 		        argv0,
  384. 		        strerror(errno));
  385. 	}
  386. 	errno = 0;
  388. #ifdef HAS_GETOPT_LONG
  389. 	// Strictly for GNUisms compatibility so no long-only options
  390. 	// clang-format off
  391. 	static struct option opts[] = {
  392. 		{"bytes", required_argument, NULL, 'b'},
  393. 		{"characters", required_argument, NULL, 'c'},
  394. 		{"delimiter", required_argument, NULL, 'd'},
  395. 		{"fields", required_argument, NULL, 'f'},
  396. 		{"only-delimited", no_argument, NULL, 's'},
  397. 		{"zero-terminated", no_argument, NULL, 'z'},
  398. 		{0, 0, 0, 0},
  399. 	};
  400. 	// clang-format on
  402. 	// Need + as first character to get POSIX-style option parsing
  403. 	for(int c = -1; (c = getopt_long(argc, argv, "+:b:c:d:f:nsz", opts, NULL)) != -1;)
  404. #else
  405. 	for(int c = -1; (c = getopt_nolong(argc, argv, ":b:c:d:f:nsz")) != -1;)
  406. #endif
  407. 	{
  408. 		switch(c)
  409. 		{
  410. 		case 'b':
  411. 			if(opt_list != NULL)
  412. 			{
  413. 				fprintf(stderr, "%s: error: Only one list may be specified\n", argv0);
  414. 				return 1;
  415. 			}
  416. 			mode = CUT_MODE_B;
  417. 			opt_list = optarg;
  418. 			break;
  419. 		case 'c':
  420. 			if(opt_list != NULL)
  421. 			{
  422. 				fprintf(stderr, "%s: error: Only one list may be specified\n", argv0);
  423. 				return 1;
  424. 			}
  425. 			mode = CUT_MODE_C;
  426. 			opt_list = optarg;
  427. 			break;
  428. 		case 'f':
  429. 			if(opt_list != NULL)
  430. 			{
  431. 				fprintf(stderr, "%s: error: Only one list may be specified\n", argv0);
  432. 				return 1;
  433. 			}
  434. 			mode = CUT_MODE_F;
  435. 			opt_list = optarg;
  436. 			break;
  437. 		case 'd':
  438. 			if(optarg[0] != '\0' && optarg[1] != '\0')
  439. 			{
  440. 				fprintf(stderr,
  441. 				        "%s: error: Option '-d' only accepts single characters, got \"%s\"\n",
  442. 				        argv0,
  443. 				        optarg);
  444. 				return 1;
  445. 			}
  446. 			delim = optarg[0];
  447. 			break;
  448. 		case 'n':
  449. 			opt_n = true;
  450. 			break;
  451. 		case 's':
  452. 			opt_s = true;
  453. 			break;
  454. 		case 'z':
  455. 			line_delim = '\0';
  456. 			line_delim_w = L'\0';
  457. 			break;
  458. 		case ':':
  459. 			fprintf(stderr, "%s: error: Option '-%c' requires an operand\n", argv0, optopt);
  460. 			return 1;
  461. 		case '?':
  462. 			GETOPT_UNKNOWN_OPT
  463. 			return 1;
  464. 		default:
  465. 			fprintf(stderr, "%s: error: Unhandled getopt case '%c'\n", argv0, c);
  466. 			abort();
  467. 		}
  468. 	}
  470. 	argc -= optind;
  471. 	argv += optind;
  473. 	if(mode == CUT_MODE_NONE)
  474. 	{
  475. 		fprintf(stderr, "%s: error: No action (-b, -c, -f) specified\n", argv0);
  476. 		return 1;
  477. 	}
  479. 	if(parse_list(opt_list) < 0) return 1;
  481. #if 0
  482. 	fprintf(stderr, "[DEBUG] list: ");
  483. 	for(size_t i = 0; i < list_len; i++)
  484. 	{
  485. 		fputc(list[i] ? '1' : '0', stderr);
  486. 	}
  487. 	fputc('\n', stderr);
  488. #endif
  490. 	if(argc <= 0) return cut(stdin, "<stdin>");
  492. 	for(int i = 0; i < argc; i++)
  493. 	{
  494. 		FILE *in = fopen(argv[i], "r");
  495. 		if(in == NULL)
  496. 		{
  497. 			fprintf(stderr, "%s: error: Failed opening file '%s': %s\n", argv0, argv[i], strerror(errno));
  498. 			return 1;
  499. 		}
  501. 		int ret = cut(in, argv[i]);
  503. 		if(fclose(in) < 0)
  504. 		{
  505. 			fprintf(stderr, "%s: error: Failed closing file '%s': %s\n", argv0, argv[i], strerror(errno));
  506. 			return 1;
  507. 		}
  509. 		if(ret != 0) return 1;
  510. 	}
  512. 	if(fclose(stdin) != 0)
  513. 	{
  514. 		fprintf(stderr, "%s: error: Failed closing <stdin>: %s\n", argv0, strerror(errno));
  515. 		return 1;
  516. 	}
  518. 	if(fclose(stdout) != 0)
  519. 	{
  520. 		fprintf(stderr, "%s: error: Failed closing <stdout>: %s\n", argv0, strerror(errno));
  521. 		return 1;
  522. 	}
  524. 	return 0;
  525. }