xref: /illumos-gate/usr/src/lib/libc/i386/sys/gettimeofday.c (revision 31aa620247ae407b2bee2dccd71693d1938f54d6)
1 /*
2  * This file and its contents are supplied under the terms of the
3  * Common Development and Distribution License ("CDDL"), version 1.0.
4  * You may only use this file in accordance with the terms of version
5  * 1.0 of the CDDL.
6  *
7  * A full copy of the text of the CDDL should have accompanied this
8  * source.  A copy of the CDDL is also available via the Internet at
9  * http://www.illumos.org/license/CDDL.
10  */
11 
12 /*
13  * Copyright (c) 2017, Joyent, Inc.
14  */
15 
16 
17 #include "thr_uberdata.h"
18 #include <cp_defs.h>
19 
20 #pragma weak _gettimeofday = gettimeofday
21 
22 extern int __clock_gettime_sys(clockid_t, timespec_t *);
23 
24 int
25 gettimeofday(struct timeval *tv, void *tz)
26 {
27 	comm_page_t *cp = (comm_page_t *)__uberdata.ub_comm_page;
28 
29 	/*
30 	 * Perform a NULL check before attempting to store the result directly.
31 	 * The old fasttrap logic would perform this same check, but after the
32 	 * call into hrestime().
33 	 */
34 	if (tv == NULL) {
35 		return (0);
36 	}
37 
38 	/*
39 	 * Since timeval and timespec structs feature the same effective types
40 	 * and layout of their members, the conversion can be done in-place.
41 	 */
42 	if (cp != NULL && __cp_can_gettime(cp) != 0) {
43 		__cp_clock_gettime_realtime(cp, (struct timespec *)tv);
44 	} else {
45 		__clock_gettime_sys(CLOCK_REALTIME, (struct timespec *)tv);
46 	}
47 	/* Convert from tv_nsec to tv_usec */
48 	tv->tv_usec /= 1000;
49 	return (0);
50 }
51