1/*
2 * Copyright (c) 2003-2005 Apple Computer, Inc. All rights reserved.
3 *
4 * @APPLE_LICENSE_HEADER_START@
5 *
6 * This file contains Original Code and/or Modifications of Original Code
7 * as defined in and that are subject to the Apple Public Source License
8 * Version 2.0 (the 'License'). You may not use this file except in
9 * compliance with the License. Please obtain a copy of the License at
10 * http://www.opensource.apple.com/apsl/ and read it before using this
11 * file.
12 *
13 * The Original Code and all software distributed under the License are
14 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
15 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
16 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
17 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
18 * Please see the License for the specific language governing rights and
19 * limitations under the License.
20 *
21 * @APPLE_LICENSE_HEADER_END@
22 */
23/*
24 * Copyright (c) 1995 NeXT Computer, Inc. All Rights Reserved
25 *
26 * 	File:	libc/sys/gettimeofday.c
27 */
28
29#include <time.h>
30#include <tzfile.h>
31#include <sys/time.h>
32#include <errno.h>
33#include <unistd.h>
34
35#define	__APPLE_API_PRIVATE
36#include <machine/cpu_capabilities.h>
37#undef	__APPLE_API_PRIVATE
38
39extern int __gettimeofday(struct timeval *, struct timezone *);
40extern int __commpage_gettimeofday(struct timeval *);
41
42int gettimeofday (struct timeval *tp, void *vtzp)
43{
44	static int validtz = 0;
45	static struct timezone cached_tz = {0};
46	struct timezone *tzp = (struct timezone *)vtzp;
47	struct timeval atv;
48
49	if (tp == NULL) {
50	    if (tzp == NULL)
51		return	(0);
52	    tp = &atv;
53	}
54
55	if (__commpage_gettimeofday(tp)) {		/* first try commpage */
56		if (__gettimeofday(tp, NULL) < 0) {	/* if it fails, use syscall */
57			return (-1);
58		}
59	}
60
61	if (tzp) {
62	    if (validtz == 0)  {
63		struct tm *localtm = localtime ((time_t *)&tp->tv_sec);
64		cached_tz.tz_dsttime = localtm->tm_isdst;
65		cached_tz.tz_minuteswest =
66		    (-localtm->tm_gmtoff / SECSPERMIN) +
67		    (localtm->tm_isdst * MINSPERHOUR);
68		validtz = 1;
69	    }
70	    tzp->tz_dsttime = cached_tz.tz_dsttime;
71	    tzp->tz_minuteswest = cached_tz.tz_minuteswest;
72	}
73	return (0);
74}
75