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~/.local/bin tools and git-hooks git clone https://hacktivis.me/git/utils.git

touch.c (2722B)

    

  1. // Collection of Unix tools, comparable to coreutils
  2. // SPDX-FileCopyrightText: 2023 Haelwenn (lanodan) Monnier <contact+utils@hacktivis.me>
  3. // SPDX-License-Identifier: MPL-2.0
  5. #define _POSIX_C_SOURCE 200809L // O_NOFOLLOW
  7. #include "../lib/iso_parse.h" /* iso_parse */
  9. #include <errno.h>    /* errno */
  10. #include <fcntl.h>    /* open */
  11. #include <stdbool.h>  /* bool */
  12. #include <stdio.h>    /* perror */
  13. #include <sys/stat.h> /* futimens, stat, utimensat */
  14. #include <unistd.h>   /* getopt, opt*, close */
  16. int
  17. main(int argc, char *argv[])
  18. {
  19. 	bool ch_atime = false, ch_mtime = false;
  20. 	char *ref_file           = NULL;
  21. 	struct timespec times[2] = {
  22. 	    {.tv_sec = 0, .tv_nsec = UTIME_OMIT}, // access
  23. 	    {.tv_sec = 0, .tv_nsec = UTIME_OMIT}  // modification
  24. 	};
  25. 	struct timespec target = {0, UTIME_NOW};
  26. 	int open_flags         = O_WRONLY | O_CREAT | O_NOCTTY;
  27. 	int utimensat_flags    = 0;
  29. 	int c = 0;
  30. 	while((c = getopt(argc, argv, ":achmr:t:d:")) != -1)
  31. 	{
  32. 		switch(c)
  33. 		{
  34. 		case 'a':
  35. 			ch_atime = true;
  36. 			break;
  37. 		case 'c':
  38. 			open_flags ^= O_CREAT;
  39. 			break;
  40. 		case 'h':
  41. 			open_flags |= O_NOFOLLOW;
  42. 			utimensat_flags |= AT_SYMLINK_NOFOLLOW;
  43. 			break;
  44. 		case 'm':
  45. 			ch_mtime = true;
  46. 			break;
  47. 		case 'r':
  48. 			ref_file = optarg;
  49. 			break;
  50. 		case 't': // [[CC]YY]MMDDhhmm[.SS]
  51. 			// Too legacy of a format, too annoying to parse
  52. 			fprintf(stderr, "touch: Option -d not supported, use -t\n");
  53. 			return 1;
  54. 			break;
  55. 		case 'd':
  56. 			target = iso_parse(optarg);
  57. 			break;
  58. 		case ':':
  59. 			fprintf(stderr, "touch: Error: Missing operand for option: '-%c'\n", optopt);
  60. 			return 1;
  61. 		case '?':
  62. 			fprintf(stderr, "touch: Error: Unrecognised option: '-%c'\n", optopt);
  63. 			return 1;
  64. 		}
  65. 	}
  67. 	argc -= optind;
  68. 	argv += optind;
  70. 	// When neither -a nor -m are specified, change both
  71. 	if(!ch_atime && !ch_mtime)
  72. 	{
  73. 		ch_atime = true;
  74. 		ch_mtime = true;
  75. 	}
  77. 	if(ref_file == NULL)
  78. 	{
  79. 		if(ch_atime) times[0] = target;
  80. 		if(ch_mtime) times[1] = target;
  81. 	}
  82. 	else
  83. 	{
  84. 		struct stat ref;
  86. 		if(stat(ref_file, &ref) != 0)
  87. 		{
  88. 			perror("touch: stat");
  89. 			return 1;
  90. 		}
  92. 		if(ch_atime)
  93. 		{
  94. 			times[0] = ref.st_atim;
  95. 		}
  96. 		if(ch_mtime)
  97. 		{
  98. 			times[1] = ref.st_mtim;
  99. 		}
  100. 	}
  102. 	for(int i = 0; i < argc; i++)
  103. 	{
  104. 		int fd = open(argv[i], open_flags, S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH);
  105. 		if(fd == -1)
  106. 		{
  107. 			if(errno == EISDIR)
  108. 			{
  109. 				if(utimensat(AT_FDCWD, argv[i], times, utimensat_flags) != 0)
  110. 				{
  111. 					perror("touch: utimensat");
  112. 					return 1;
  113. 				}
  115. 				return 0;
  116. 			}
  117. 			if(errno != ENOENT) perror("touch: open");
  119. 			return 1;
  120. 		}
  122. 		if(futimens(fd, times) != 0)
  123. 		{
  124. 			perror("touch: futimens");
  125. 			return 1;
  126. 		}
  128. 		if(close(fd) != 0)
  129. 		{
  130. 			perror("touch: close");
  131. 			return 1;
  132. 		}
  133. 	}
  135. 	return 0;
  136. }