1/***********************************************************************
2*                                                                      *
3*               This software is part of the ast package               *
4*          Copyright (c) 1985-2011 AT&T Intellectual Property          *
5*                      and is licensed under the                       *
6*                 Eclipse Public License, Version 1.0                  *
7*                    by AT&T Intellectual Property                     *
8*                                                                      *
9*                A copy of the License is available at                 *
10*          http://www.eclipse.org/org/documents/epl-v10.html           *
11*         (with md5 checksum b35adb5213ca9657e911e9befb180842)         *
12*                                                                      *
13*              Information and Software Systems Research               *
14*                            AT&T Research                             *
15*                           Florham Park NJ                            *
16*                                                                      *
17*                 Glenn Fowler <gsf@research.att.com>                  *
18*                  David Korn <dgk@research.att.com>                   *
19*                   Phong Vo <kpv@research.att.com>                    *
20*                                                                      *
21***********************************************************************/
22#pragma prototyped
23/*
24 * Glenn Fowler
25 * AT&T Research
26 *
27 * Time_t conversion support
28 */
29
30#include <tmx.h>
31
32#include "FEATURE/tmlib"
33
34/*
35 * convert Tm_t to Time_t
36 *
37 * if west==TM_LOCALZONE then the local timezone is used
38 * otherwise west is the number of minutes west
39 * of GMT with DST taken into account
40 *
41 * this routine works with a copy of Tm_t to avoid clashes
42 * with other tm*() that may return static Tm_t*
43 */
44
45Time_t
46tmxtime(register Tm_t* tm, int west)
47{
48	register Time_t		t;
49	register Tm_leap_t*	lp;
50	register int32_t	y;
51	int			n;
52	int			sec;
53	time_t			now;
54	struct tm*		tl;
55	Tm_t*			to;
56	Tm_t			ts;
57
58	ts = *tm;
59	to = tm;
60	tm = &ts;
61	tmset(tm_info.zone);
62	tmfix(tm);
63	y = tm->tm_year;
64	if (y < 69 || y > (TMX_MAXYEAR - 1900))
65		return TMX_NOTIME;
66	y--;
67	t = y * 365 + y / 4 - y / 100 + (y + (1900 - 1600)) / 400 - (1970 - 1901) * 365 - (1970 - 1901) / 4;
68	if ((n = tm->tm_mon) > 11)
69		n = 11;
70	y += 1901;
71	if (n > 1 && tmisleapyear(y))
72		t++;
73	t += tm_data.sum[n] + tm->tm_mday - 1;
74	t *= 24;
75	t += tm->tm_hour;
76	t *= 60;
77	t += tm->tm_min;
78	t *= 60;
79	t += sec = tm->tm_sec;
80	if (west != TM_UTCZONE && !(tm_info.flags & TM_UTC))
81	{
82		/*
83		 * time zone adjustments
84		 */
85
86		if (west == TM_LOCALZONE)
87		{
88			t += tm_info.zone->west * 60;
89			if (!tm_info.zone->daylight)
90				tm->tm_isdst = 0;
91			else
92			{
93				y = tm->tm_year;
94				tm->tm_year = tmequiv(tm) - 1900;
95				now = tmxsec(tmxtime(tm, tm_info.zone->west));
96				tm->tm_year = y;
97				if (!(tl = tmlocaltime(&now)))
98					return TMX_NOTIME;
99				if (tm->tm_isdst = tl->tm_isdst)
100					t += tm_info.zone->dst * 60;
101			}
102		}
103		else
104		{
105			t += west * 60;
106			if (!tm_info.zone->daylight)
107				tm->tm_isdst = 0;
108			else if (tm->tm_isdst < 0)
109			{
110				y = tm->tm_year;
111				tm->tm_year = tmequiv(tm) - 1900;
112				tm->tm_isdst = 0;
113				now = tmxsec(tmxtime(tm, tm_info.zone->west));
114				tm->tm_year = y;
115				if (!(tl = tmlocaltime(&now)))
116					return TMX_NOTIME;
117				tm->tm_isdst = tl->tm_isdst;
118			}
119		}
120	}
121	else if (tm->tm_isdst)
122		tm->tm_isdst = 0;
123	*to = *tm;
124	if (tm_info.flags & TM_LEAP)
125	{
126		/*
127		 * leap second adjustments
128		 */
129
130		for (lp = &tm_data.leap[0]; t < lp->time - (lp+1)->total; lp++);
131		t += lp->total;
132		n = lp->total - (lp+1)->total;
133		if (t <= (lp->time + n) && (n > 0 && sec > 59 || n < 0 && sec > (59 + n) && sec <= 59))
134			t -= n;
135	}
136	return tmxsns(t, tm->tm_nsec);
137}
138