1/* See LICENSE file for copyright and license details. */
 2
 3
 4#include <sys/times.h>
 5#include <sys/wait.h>
 6
 7#include <errno.h>
 8#include <stdio.h>
 9#include <unistd.h>
10
11#include "util.h"
12
13static void
14usage(void)
15{
16	eprintf("usage: %s [-p] cmd [arg ...]\n", argv0);
17}
18
19// ?man time: time command execution
20// ?man arguments: cmd [arg ...
21// ?man run a command and report its execution duration
22int
23main(int argc, char *argv[])
24{
25	pid_t pid;
26	struct tms tms; /* user and sys times */
27	clock_t r0, r1; /* real time */
28	long ticks;     /* per second */
29	int status, savederrno, ret = 0;
30
31	ARGBEGIN {
32	// ?man -p: preserve file attributes
33	case 'p':
34		break;
35	default:
36		usage();
37	} ARGEND
38
39	if (!argc)
40		usage();
41
42	if ((ticks = sysconf(_SC_CLK_TCK)) <= 0)
43		eprintf("sysconf _SC_CLK_TCK:");
44
45	if ((r0 = times(&tms)) == (clock_t)-1)
46		eprintf("times:");
47
48	switch ((pid = fork())) {
49	case -1:
50		eprintf("fork:");
51		/* fallthrough */
52	case 0:
53		execvp(argv[0], argv);
54		savederrno = errno;
55		weprintf("execvp %s:", argv[0]);
56		_exit(126 + (savederrno == ENOENT));
57	default:
58		break;
59	}
60	waitpid(pid, &status, 0);
61
62	if ((r1 = times(&tms)) == (clock_t)-1)
63		eprintf("times:");
64
65	if (WIFSIGNALED(status)) {
66		fprintf(stderr, "Command terminated by signal %d\n",
67		        WTERMSIG(status));
68		ret = 128 + WTERMSIG(status);
69	}
70
71	fprintf(stderr, "real %f\nuser %f\nsys %f\n",
72	        (r1 - r0)      / (double)ticks,
73	        tms.tms_cutime / (double)ticks,
74	        tms.tms_cstime / (double)ticks);
75
76	if (WIFEXITED(status))
77		ret = WEXITSTATUS(status);
78
79	return ret;
80}