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 * return Tm_t for t
36 * time zone and leap seconds accounted for in return value
37 */
38
39Tm_t*
40tmxtm(register Tm_t* tm, Time_t t, Tm_zone_t* zone)
41{
42	register struct tm*	tp;
43	register Tm_leap_t*	lp;
44	Time_t			x;
45	time_t			now;
46	int			leapsec;
47	int			y;
48	uint32_t		n;
49	int32_t			o;
50#if TMX_FLOAT
51	Time_t			z;
52	uint32_t		i;
53#endif
54
55	tmset(tm_info.zone);
56	leapsec = 0;
57	if ((tm_info.flags & (TM_ADJUST|TM_LEAP)) == (TM_ADJUST|TM_LEAP) && (n = tmxsec(t)))
58	{
59		for (lp = &tm_data.leap[0]; n < lp->time; lp++);
60		if (lp->total)
61		{
62			if (n == lp->time && (leapsec = (lp->total - (lp+1)->total)) < 0)
63				leapsec = 0;
64			t = tmxsns(n - lp->total, tmxnsec(t));
65		}
66	}
67	x = tmxsec(t);
68	if (!(tm->tm_zone = zone))
69	{
70		if (tm_info.flags & TM_UTC)
71			tm->tm_zone = &tm_data.zone[2];
72		else
73			tm->tm_zone = tm_info.zone;
74	}
75	if ((o = 60 * tm->tm_zone->west) && x > o)
76	{
77		x -= o;
78		o = 0;
79	}
80#if TMX_FLOAT
81	i = x / (24 * 60 * 60);
82	z = i;
83	n = x - z * (24 * 60 * 60);
84	tm->tm_sec = n % 60 + leapsec;
85	n /= 60;
86	tm->tm_min = n % 60;
87	n /= 60;
88	tm->tm_hour = n % 24;
89#define x	i
90#else
91	tm->tm_sec = x % 60 + leapsec;
92	x /= 60;
93	tm->tm_min = x % 60;
94	x /= 60;
95	tm->tm_hour = x % 24;
96	x /= 24;
97#endif
98	tm->tm_wday = (x + 4) % 7;
99	tm->tm_year = (400 * (x + 25202)) / 146097 + 1;
100	n = tm->tm_year - 1;
101	x -= n * 365 + n / 4 - n / 100 + (n + (1900 - 1600)) / 400 - (1970 - 1901) * 365 - (1970 - 1901) / 4;
102	tm->tm_mon = 0;
103	tm->tm_mday = x + 1;
104	tm->tm_nsec = tmxnsec(t);
105	tmfix(tm);
106	n += 1900;
107	tm->tm_isdst = 0;
108	if (tm->tm_zone->daylight)
109	{
110		if ((y = tmequiv(tm) - 1900) == tm->tm_year)
111			now = tmxsec(t);
112		else
113		{
114			Tm_t	te;
115
116			te = *tm;
117			te.tm_year = y;
118			now = tmxsec(tmxtime(&te, tm->tm_zone->west));
119		}
120		if ((tp = tmlocaltime(&now)) && ((tm->tm_isdst = tp->tm_isdst) || o))
121		{
122			tm->tm_min -= o / 60 + (tm->tm_isdst ? tm->tm_zone->dst : 0);
123			tmfix(tm);
124		}
125	}
126	return tm;
127}
128
129/*
130 * return Tm_t for t
131 * time zone and leap seconds accounted for in return value
132 */
133
134Tm_t*
135tmxmake(Time_t t)
136{
137	static Tm_t		ts;
138
139	return tmxtm(&ts, t, NiL);
140}
141