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utils-std

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

time.c (3685B)

    

  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 200809L
  6. #include <errno.h>        // errno
  7. #include <stdio.h>        // perror, fprintf
  8. #include <stdlib.h>       // abort
  9. #include <string.h>       // strerror
  10. #include <sys/resource.h> // getrusage
  11. #include <sys/times.h>    // times
  12. #include <sys/wait.h>     // waitpid
  13. #include <unistd.h>       // sysconf, fork, execvp, getopt
  15. enum cmd_time_mode
  16. {
  17. 	CMD_TIME_POSIX = 0,
  18. 	CMD_TIME_VERBOSE = 1,
  19. };
  21. static void
  22. usage(void)
  23. {
  24. 	fprintf(stderr, "Usage: time [-p|-v] command [argument ...]\n");
  25. }
  27. int
  28. main(int argc, char *argv[])
  29. {
  30. 	struct tms tms;
  31. 	int ret = 0;
  32. 	enum cmd_time_mode mode = CMD_TIME_POSIX;
  34. 	if(argc <= 1)
  35. 	{
  36. 		usage();
  37. 		return 0;
  38. 	}
  40. 	for(int c = -1; (c = getopt(argc, argv, ":pv")) != -1;)
  41. 	{
  42. 		switch(c)
  43. 		{
  44. 		case 'p': // POSIX format (default)
  45. 			mode = CMD_TIME_POSIX;
  46. 			break;
  47. 		case 'v':
  48. 			mode = CMD_TIME_VERBOSE;
  49. 			break;
  50. 		case ':':
  51. 			fprintf(stderr, "time: error: Missing operand for option: '-%c'\n", optopt);
  52. 			usage();
  53. 			return 1;
  54. 		case '?':
  55. 			fprintf(stderr, "time: error: Unrecognised option: '-%c'\n", optopt);
  56. 			usage();
  57. 			return 1;
  58. 		}
  59. 	}
  61. 	argc -= optind;
  62. 	argv += optind;
  63. 	(void)argc;
  65. 	long ticks = sysconf(_SC_CLK_TCK);
  66. 	if(ticks <= 0)
  67. 	{
  68. 		perror("time: error: sysconf(_SC_CLK_TCK)");
  69. 		return 1;
  70. 	}
  72. 	clock_t t0 = times(&tms);
  73. 	if(t0 == (clock_t)-1)
  74. 	{
  75. 		perror("time: error: times");
  76. 		return 1;
  77. 	}
  79. 	// Note: posix_spawnp seems to lack enough error information
  80. 	pid_t pid = fork();
  81. 	switch(pid)
  82. 	{
  83. 	case -1:
  84. 		perror("time: error: fork");
  85. 		return 1;
  86. 	case 0:
  87. 		execvp(argv[0], argv);
  88. 		ret = 126 + (errno == ENOENT);
  89. 		fprintf(stderr, "time: error: Failed executing '%s': %s\n", argv[0], strerror(errno));
  90. 		return ret;
  91. 	default:
  92. 		break;
  93. 	}
  95. 	int status = 0;
  96. 	waitpid(pid, &status, 0);
  98. 	int t1 = times(&tms);
  99. 	if(t1 == (clock_t)-1)
  100. 	{
  101. 		perror("time: error: times");
  102. 		return 1;
  103. 	}
  105. 	if(WIFSIGNALED(status))
  106. 	{
  107. 		fprintf(stderr, "time: error: Command terminated by signal %d\n", WTERMSIG(status));
  108. 		ret = 128 + WTERMSIG(status);
  109. 	}
  111. 	struct rusage usage;
  112. 	if(getrusage(RUSAGE_CHILDREN, &usage) != 0)
  113. 	{
  114. 		fprintf(
  115. 		    stderr, "time: error: Failed getting resource usage of children: %s\n", strerror(errno));
  116. 		return 1;
  117. 	}
  119. 	double utime_s = usage.ru_utime.tv_sec + (usage.ru_utime.tv_usec * 0.000001);
  120. 	double stime_s = usage.ru_stime.tv_sec + (usage.ru_stime.tv_usec * 0.000001);
  122. 	switch(mode)
  123. 	{
  124. 	case CMD_TIME_POSIX:
  125. 		fprintf(stderr, "real %f\nuser %f\nsys %f\n", (t1 - t0) / (double)ticks, utime_s, stime_s);
  126. 		break;
  127. 	case CMD_TIME_VERBOSE:
  128. 		fprintf(stderr, "\tExecutable: %s\n", argv[0]);
  129. 		fprintf(stderr, "\tReal time  : %06f\n", (t1 - t0) / (double)ticks);
  130. 		fprintf(stderr, "\tUser time  : %06f\n", utime_s);
  131. 		fprintf(stderr, "\tSystem time: %06f\n", stime_s);
  132. #ifdef __linux__
  133. 		fprintf(stderr, "\tMaximum resident set size (maxrss): %ld kB\n", usage.ru_maxrss);
  134. 		fprintf(stderr, "\tMinor (no I/O required) page faults (minflt): %ld\n", usage.ru_minflt);
  135. 		fprintf(stderr, "\tMajor (I/O required) page faults (majflt): %ld\n", usage.ru_majflt);
  136. 		fprintf(stderr, "\tMajor (I/O required) page faults (majflt): %ld\n", usage.ru_majflt);
  137. 		fprintf(stderr, "\tVoluntary context switch (nvcsw): %ld\n", usage.ru_nvcsw);
  138. 		fprintf(stderr, "\tInvoluntary context switch (nivcsw): %ld\n", usage.ru_nivcsw);
  139. #endif
  141. 		if(WIFEXITED(status)) fprintf(stderr, "\tExit status: %d\n", WEXITSTATUS(status));
  143. 		break;
  144. 	default:
  145. 		abort();
  146. 	}
  148. 	if(WIFEXITED(status))
  149. 	{
  150. 		ret = WEXITSTATUS(status);
  151. 	}
  153. 	return ret;
  154. }