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utils-std

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

time.c (3683B)

    

  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. 	int c = -1;
  41. 	while((c = getopt(argc, argv, ":pv")) != -1)
  42. 	{
  43. 		switch(c)
  44. 		{
  45. 		case 'p': // POSIX format (default)
  46. 			mode = CMD_TIME_POSIX;
  47. 			break;
  48. 		case 'v':
  49. 			mode = CMD_TIME_VERBOSE;
  50. 			break;
  51. 		case ':':
  52. 			fprintf(stderr, "time: error: Missing operand for option: '-%c'\n", optopt);
  53. 			usage();
  54. 			return 1;
  55. 		case '?':
  56. 			fprintf(stderr, "time: error: Unrecognised option: '-%c'\n", optopt);
  57. 			usage();
  58. 			return 1;
  59. 		}
  60. 	}
  62. 	argc -= optind;
  63. 	argv += optind;
  64. 	(void)argc;
  66. 	long ticks = sysconf(_SC_CLK_TCK);
  67. 	if(ticks <= 0)
  68. 	{
  69. 		perror("time: error: sysconf(_SC_CLK_TCK)");
  70. 		return 1;
  71. 	}
  73. 	clock_t t0 = times(&tms);
  74. 	if(t0 == (clock_t)-1)
  75. 	{
  76. 		perror("time: error: times");
  77. 		return 1;
  78. 	}
  80. 	// Note: posix_spawnp seems to lack enough error information
  81. 	pid_t pid = fork();
  82. 	switch(pid)
  83. 	{
  84. 	case -1:
  85. 		perror("time: error: fork");
  86. 		return 1;
  87. 	case 0:
  88. 		execvp(argv[0], argv);
  89. 		ret = 126 + (errno == ENOENT);
  90. 		fprintf(stderr, "time: error: Failed executing '%s': %s\n", argv[0], strerror(errno));
  91. 		return ret;
  92. 	default:
  93. 		break;
  94. 	}
  96. 	int status = 0;
  97. 	waitpid(pid, &status, 0);
  99. 	int t1 = times(&tms);
  100. 	if(t1 == (clock_t)-1)
  101. 	{
  102. 		perror("time: error: times");
  103. 		return 1;
  104. 	}
  106. 	if(WIFSIGNALED(status))
  107. 	{
  108. 		fprintf(stderr, "time: error: Command terminated by signal %d\n", WTERMSIG(status));
  109. 		ret = 128 + WTERMSIG(status);
  110. 	}
  112. 	struct rusage usage;
  113. 	if(getrusage(RUSAGE_CHILDREN, &usage) != 0)
  114. 	{
  115. 		fprintf(
  116. 		    stderr, "time: error: Failed getting resource usage of children: %s\n", strerror(errno));
  117. 		return 1;
  118. 	}
  120. 	double utime_s = usage.ru_utime.tv_sec + (usage.ru_utime.tv_usec * 0.000001);
  121. 	double stime_s = usage.ru_stime.tv_sec + (usage.ru_stime.tv_usec * 0.000001);
  123. 	switch(mode)
  124. 	{
  125. 	case CMD_TIME_POSIX:
  126. 		fprintf(stderr, "real %f\nuser %f\nsys %f\n", (t1 - t0) / (double)ticks, utime_s, stime_s);
  127. 		break;
  128. 	case CMD_TIME_VERBOSE:
  129. 		fprintf(stderr, "\tExecutable: %s\n", argv[0]);
  130. 		fprintf(stderr, "\tReal time: %06f\n", (t1 - t0) / (double)ticks);
  131. 		fprintf(stderr, "\tUser time: %06f\n", utime_s);
  132. 		fprintf(stderr, "\tSystem time: %06f\n", stime_s);
  133. #ifdef __linux__
  134. 		fprintf(stderr, "\tMaximum resident set size (maxrss): %ld kB\n", usage.ru_maxrss);
  135. 		fprintf(stderr, "\tMinor (no I/O required) page faults (minflt): %ld\n", usage.ru_minflt);
  136. 		fprintf(stderr, "\tMajor (I/O required) page faults (majflt): %ld\n", usage.ru_majflt);
  137. 		fprintf(stderr, "\tMajor (I/O required) page faults (majflt): %ld\n", usage.ru_majflt);
  138. 		fprintf(stderr, "\tVoluntary context switch (nvcsw): %ld\n", usage.ru_nvcsw);
  139. 		fprintf(stderr, "\tInvoluntary context switch (nivcsw): %ld\n", usage.ru_nivcsw);
  140. #endif
  142. 		if(WIFEXITED(status)) fprintf(stderr, "\tExit status: %d\n", WEXITSTATUS(status));
  144. 		break;
  145. 	default:
  146. 		abort();
  147. 	}
  149. 	if(WIFEXITED(status))
  150. 	{
  151. 		ret = WEXITSTATUS(status);
  152. 	}
  154. 	return ret;
  155. }