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

humanize.c (2025B)

    

  1. // Collection of Unix tools, comparable to coreutils
  2. // SPDX-FileCopyrightText: 2017-2022 Haelwenn (lanodan) Monnier <contact+utils@hacktivis.me>
  3. // SPDX-License-Identifier: GPL-2.0-only OR GPL-3.0-only
  5. #define _DEFAULT_SOURCE
  6. // strtonum
  7. #define _OPENBSD_SOURCE
  8. // On non-BSDs use libbsd
  9. #include <err.h>     // errx
  10. #include <errno.h>   // EINVAL, ERANGE
  11. #include <limits.h>  // LLONG_MIN, LLONG_MAX
  12. #include <stdbool.h> // bool
  13. #include <stdio.h>   // fprintf
  14. #include <stdlib.h>  // strtonum
  15. #include <string.h>  // strerror
  16. #include <unistd.h>  // opt*, getopt
  18. void
  19. dtosi(double num, char *buf, size_t bufsize, bool iec)
  20. {
  21. 	char *si_prefixes[9]  = {"", "k", "M", "G", "T", "P", "E", "Z", "Y"};
  22. 	char *iec_prefixes[9] = {"B", "KiB", "MiB", "GiB", "TiB", "PiB", "EiB", "ZiB", "YiB"};
  24. 	int div         = iec ? 1024 : 1000;
  25. 	char **prefixes = iec ? iec_prefixes : si_prefixes;
  27. 	unsigned quotient = 0;
  29. 	while(num > div && quotient < 9)
  30. 	{
  31. 		num /= div;
  32. 		quotient += 1;
  33. 	}
  35. 	snprintf(buf, bufsize, "%g %s", num, prefixes[quotient]);
  36. }
  38. static void
  39. usage()
  40. {
  41. 	fprintf(stderr, "Usage: humanize [-bd] number\n");
  42. }
  44. int
  45. main(int argc, char *argv[])
  46. {
  47. 	// default to -d
  48. 	bool iec = false;
  50. 	int c = -1;
  51. 	while((c = getopt(argc, argv, ":bd")) != -1)
  52. 	{
  53. 		switch(c)
  54. 		{
  55. 		case 'b':
  56. 			iec = true;
  57. 			break;
  58. 		case 'd':
  59. 			iec = false;
  60. 			break;
  61. 		case ':':
  62. 			fprintf(stderr, "Error: Missing operand for option: '-%c'\n", optopt);
  63. 			usage();
  64. 			return 1;
  65. 		case '?':
  66. 			fprintf(stderr, "Error: Unrecognised option: '-%c'\n", optopt);
  67. 			usage();
  68. 			return 1;
  69. 		}
  70. 	}
  72. 	argc -= optind;
  73. 	argv += optind;
  75. 	if(argc < 1)
  76. 	{
  77. 		usage();
  78. 		return 1;
  79. 	}
  81. 	for(int argi = 0; argi < argc; argi++)
  82. 	{
  83. 		const char *errstr = NULL;
  84. 		char buf[32]       = "";
  86. 		// 1024^(6+1) goes higher than long long; don't ask for the moon
  87. 		long long n = strtonum(argv[argi], LLONG_MIN, LLONG_MAX, &errstr);
  88. 		if(errstr)
  89. 		{
  90. 			errx(1, "strtonum: %s is %s", argv[argi], errstr);
  91. 		}
  93. 		dtosi(n, buf, 32, iec);
  95. 		printf("%s\n", buf);
  96. 	}
  98. 	return 0;
  99. }