time.cpp@ 18096

Last change on this file since 18096 was 14318, checked in by vboxsync, 16 years ago
Fix a couple of words doubled in comments. No code changes.
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1	/* $Id: time.cpp 14318 2008-11-18 16:56:53Z vboxsync $ */
2	/** @file
3	* IPRT - Time.
4	*/
5
6	/*
7	* Copyright (C) 2006-2007 Sun Microsystems, Inc.
8	*
9	* This file is part of VirtualBox Open Source Edition (OSE), as
10	* available from http://www.virtualbox.org. This file is free software;
11	* you can redistribute it and/or modify it under the terms of the GNU
12	* General Public License (GPL) as published by the Free Software
13	* Foundation, in version 2 as it comes in the "COPYING" file of the
14	* VirtualBox OSE distribution. VirtualBox OSE is distributed in the
15	* hope that it will be useful, but WITHOUT ANY WARRANTY of any kind.
16	*
17	* The contents of this file may alternatively be used under the terms
18	* of the Common Development and Distribution License Version 1.0
19	* (CDDL) only, as it comes in the "COPYING.CDDL" file of the
20	* VirtualBox OSE distribution, in which case the provisions of the
21	* CDDL are applicable instead of those of the GPL.
22	*
23	* You may elect to license modified versions of this file under the
24	* terms and conditions of either the GPL or the CDDL or both.
25	*
26	* Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa
27	* Clara, CA 95054 USA or visit http://www.sun.com if you need
28	* additional information or have any questions.
29	*/
30
31
32	/*******************************************************************************
33	* Header Files *
34	*******************************************************************************/
35	#define LOG_GROUP RTLOGGROUP_TIME
36	#include <iprt/time.h>
37	#include <iprt/string.h>
38	#include <iprt/assert.h>
39	#include "internal/time.h"
40
41
42	/*******************************************************************************
43	* Defined Constants And Macros *
44	*******************************************************************************/
45	/** The max year we possibly could implode. */
46	#define RTTIME_MAX_YEAR (292 + 1970)
47	/** The min year we possibly could implode. */
48	#define RTTIME_MIN_YEAR (-293 + 1970)
49
50	/** The max day supported by our time representation. (2262-04-11T23-47-16.854775807) */
51	#define RTTIME_MAX_DAY (365*292+71 + 101-1)
52	/** The min day supported by our time representation. (1677-09-21T00-12-43.145224192) */
53	#define RTTIME_MIN_DAY (365*-293-70 + 264-1)
54
55	/** The max nano second into the max day. (2262-04-11T23-47-16.854775807) */
56	#define RTTIME_MAX_DAY_NANO ( INT64_C(1000000000) * (233600 + 4760 + 16) + 854775807 )
57	/** The min nano second into the min day. (1677-09-21T00-12-43.145224192) */
58	#define RTTIME_MIN_DAY_NANO ( INT64_C(1000000000) * (003600 + 1260 + 43) + 145224192 )
59
60
61	/*******************************************************************************
62	* Global Variables *
63	*******************************************************************************/
64	/**
65	* Days per month in a common year.
66	*/
67	static const uint8_t g_acDaysInMonths[12] =
68	{
69	/Jan Feb Mar Arp May Jun Jul Aug Sep Oct Nov Dec /
70	31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31
71	};
72
73	/**
74	* Days per month in a leap year.
75	*/
76	static const uint8_t g_acDaysInMonthsLeap[12] =
77	{
78	/Jan Feb Mar Arp May Jun Jul Aug Sep Oct Nov Dec /
79	31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31
80	};
81
82	/**
83	* The day of year for each month in a common year.
84	*/
85	static const uint16_t g_aiDayOfYear[12 + 1] =
86	{
87	1, /* Jan */
88	1+31, /* Feb */
89	1+31+28, /* Mar */
90	1+31+28+31, /* Apr */
91	1+31+28+31+30, /* May */
92	1+31+28+31+30+31, /* Jun */
93	1+31+28+31+30+31+30, /* Jul */
94	1+31+28+31+30+31+30+31, /* Aug */
95	1+31+28+31+30+31+30+31+31, /* Sep */
96	1+31+28+31+30+31+30+31+31+30, /* Oct */
97	1+31+28+31+30+31+30+31+31+30+31, /* Nov */
98	1+31+28+31+30+31+30+31+31+30+31+30, /* Dec */
99	1+31+28+31+30+31+30+31+31+30+31+30+31
100	};
101
102	/**
103	* The day of year for each month in a leap year.
104	*/
105	static const uint16_t g_aiDayOfYearLeap[12 + 1] =
106	{
107	1, /* Jan */
108	1+31, /* Feb */
109	1+31+29, /* Mar */
110	1+31+29+31, /* Apr */
111	1+31+29+31+30, /* May */
112	1+31+29+31+30+31, /* Jun */
113	1+31+29+31+30+31+30, /* Jul */
114	1+31+29+31+30+31+30+31, /* Aug */
115	1+31+29+31+30+31+30+31+31, /* Sep */
116	1+31+29+31+30+31+30+31+31+30, /* Oct */
117	1+31+29+31+30+31+30+31+31+30+31, /* Nov */
118	1+31+29+31+30+31+30+31+31+30+31+30, /* Dec */
119	1+31+29+31+30+31+30+31+31+30+31+30+31
120	};
121
122	/** The index of 1970 in g_aoffYear */
123	#define OFF_YEAR_IDX_EPOCH 300
124	/** The year of the first index. */
125	#define OFF_YEAR_IDX_0_YEAR 1670
126
127	/**
128	* The number of days the 1st of january a year is offseted from 1970-01-01.
129	*/
130	static const int32_t g_aoffYear[] =
131	{
132	/1670:/ 365-300+-72, 365-299+-72, 365-298+-72, 365-297+-71, 365-296+-71, 365-295+-71, 365-294+-71, 365-293+-70, 365-292+-70, 365-291+-70,
133	/1680:/ 365-290+-70, 365-289+-69, 365-288+-69, 365-287+-69, 365-286+-69, 365-285+-68, 365-284+-68, 365-283+-68, 365-282+-68, 365-281+-67,
134	/1690:/ 365-280+-67, 365-279+-67, 365-278+-67, 365-277+-66, 365-276+-66, 365-275+-66, 365-274+-66, 365-273+-65, 365-272+-65, 365-271+-65,
135	/1700:/ 365-270+-65, 365-269+-65, 365-268+-65, 365-267+-65, 365-266+-65, 365-265+-64, 365-264+-64, 365-263+-64, 365-262+-64, 365-261+-63,
136	/1710:/ 365-260+-63, 365-259+-63, 365-258+-63, 365-257+-62, 365-256+-62, 365-255+-62, 365-254+-62, 365-253+-61, 365-252+-61, 365-251+-61,
137	/1720:/ 365-250+-61, 365-249+-60, 365-248+-60, 365-247+-60, 365-246+-60, 365-245+-59, 365-244+-59, 365-243+-59, 365-242+-59, 365-241+-58,
138	/1730:/ 365-240+-58, 365-239+-58, 365-238+-58, 365-237+-57, 365-236+-57, 365-235+-57, 365-234+-57, 365-233+-56, 365-232+-56, 365-231+-56,
139	/1740:/ 365-230+-56, 365-229+-55, 365-228+-55, 365-227+-55, 365-226+-55, 365-225+-54, 365-224+-54, 365-223+-54, 365-222+-54, 365-221+-53,
140	/1750:/ 365-220+-53, 365-219+-53, 365-218+-53, 365-217+-52, 365-216+-52, 365-215+-52, 365-214+-52, 365-213+-51, 365-212+-51, 365-211+-51,
141	/1760:/ 365-210+-51, 365-209+-50, 365-208+-50, 365-207+-50, 365-206+-50, 365-205+-49, 365-204+-49, 365-203+-49, 365-202+-49, 365-201+-48,
142	/1770:/ 365-200+-48, 365-199+-48, 365-198+-48, 365-197+-47, 365-196+-47, 365-195+-47, 365-194+-47, 365-193+-46, 365-192+-46, 365-191+-46,
143	/1780:/ 365-190+-46, 365-189+-45, 365-188+-45, 365-187+-45, 365-186+-45, 365-185+-44, 365-184+-44, 365-183+-44, 365-182+-44, 365-181+-43,
144	/1790:/ 365-180+-43, 365-179+-43, 365-178+-43, 365-177+-42, 365-176+-42, 365-175+-42, 365-174+-42, 365-173+-41, 365-172+-41, 365-171+-41,
145	/1800:/ 365-170+-41, 365-169+-41, 365-168+-41, 365-167+-41, 365-166+-41, 365-165+-40, 365-164+-40, 365-163+-40, 365-162+-40, 365-161+-39,
146	/1810:/ 365-160+-39, 365-159+-39, 365-158+-39, 365-157+-38, 365-156+-38, 365-155+-38, 365-154+-38, 365-153+-37, 365-152+-37, 365-151+-37,
147	/1820:/ 365-150+-37, 365-149+-36, 365-148+-36, 365-147+-36, 365-146+-36, 365-145+-35, 365-144+-35, 365-143+-35, 365-142+-35, 365-141+-34,
148	/1830:/ 365-140+-34, 365-139+-34, 365-138+-34, 365-137+-33, 365-136+-33, 365-135+-33, 365-134+-33, 365-133+-32, 365-132+-32, 365-131+-32,
149	/1840:/ 365-130+-32, 365-129+-31, 365-128+-31, 365-127+-31, 365-126+-31, 365-125+-30, 365-124+-30, 365-123+-30, 365-122+-30, 365-121+-29,
150	/1850:/ 365-120+-29, 365-119+-29, 365-118+-29, 365-117+-28, 365-116+-28, 365-115+-28, 365-114+-28, 365-113+-27, 365-112+-27, 365-111+-27,
151	/1860:/ 365-110+-27, 365-109+-26, 365-108+-26, 365-107+-26, 365-106+-26, 365-105+-25, 365-104+-25, 365-103+-25, 365-102+-25, 365-101+-24,
152	/1870:/ 365-100+-24, 365 -99+-24, 365* -98+-24, 365* -97+-23, 365* -96+-23, 365* -95+-23, 365* -94+-23, 365* -93+-22, 365* -92+-22, 365* -91+-22,
153	/1880:/ 365* -90+-22, 365* -89+-21, 365* -88+-21, 365* -87+-21, 365* -86+-21, 365* -85+-20, 365* -84+-20, 365* -83+-20, 365* -82+-20, 365* -81+-19,
154	/1890:/ 365* -80+-19, 365* -79+-19, 365* -78+-19, 365* -77+-18, 365* -76+-18, 365* -75+-18, 365* -74+-18, 365* -73+-17, 365* -72+-17, 365* -71+-17,
155	/1900:/ 365* -70+-17, 365* -69+-17, 365* -68+-17, 365* -67+-17, 365* -66+-17, 365* -65+-16, 365* -64+-16, 365* -63+-16, 365* -62+-16, 365* -61+-15,
156	/1910:/ 365* -60+-15, 365* -59+-15, 365* -58+-15, 365* -57+-14, 365* -56+-14, 365* -55+-14, 365* -54+-14, 365* -53+-13, 365* -52+-13, 365* -51+-13,
157	/1920:/ 365* -50+-13, 365* -49+-12, 365* -48+-12, 365* -47+-12, 365* -46+-12, 365* -45+-11, 365* -44+-11, 365* -43+-11, 365* -42+-11, 365* -41+-10,
158	/1930:/ 365* -40+-10, 365* -39+-10, 365* -38+-10, 365* -37+-9 , 365* -36+-9 , 365* -35+-9 , 365* -34+-9 , 365* -33+-8 , 365* -32+-8 , 365* -31+-8 ,
159	/1940:/ 365* -30+-8 , 365* -29+-7 , 365* -28+-7 , 365* -27+-7 , 365* -26+-7 , 365* -25+-6 , 365* -24+-6 , 365* -23+-6 , 365* -22+-6 , 365* -21+-5 ,
160	/1950:/ 365* -20+-5 , 365* -19+-5 , 365* -18+-5 , 365* -17+-4 , 365* -16+-4 , 365* -15+-4 , 365* -14+-4 , 365* -13+-3 , 365* -12+-3 , 365* -11+-3 ,
161	/1960:/ 365* -10+-3 , 365* -9+-2 , 365* -8+-2 , 365* -7+-2 , 365* -6+-2 , 365* -5+-1 , 365* -4+-1 , 365* -3+-1 , 365* -2+-1 , 365* -1+0 ,
162	/1970:/ 365* 0+0 , 365* 1+0 , 365* 2+0 , 365* 3+1 , 365* 4+1 , 365* 5+1 , 365* 6+1 , 365* 7+2 , 365* 8+2 , 365* 9+2 ,
163	/1980:/ 365* 10+2 , 365* 11+3 , 365* 12+3 , 365* 13+3 , 365* 14+3 , 365* 15+4 , 365* 16+4 , 365* 17+4 , 365* 18+4 , 365* 19+5 ,
164	/1990:/ 365* 20+5 , 365* 21+5 , 365* 22+5 , 365* 23+6 , 365* 24+6 , 365* 25+6 , 365* 26+6 , 365* 27+7 , 365* 28+7 , 365* 29+7 ,
165	/2000:/ 365* 30+7 , 365* 31+8 , 365* 32+8 , 365* 33+8 , 365* 34+8 , 365* 35+9 , 365* 36+9 , 365* 37+9 , 365* 38+9 , 365* 39+10 ,
166	/2010:/ 365* 40+10 , 365* 41+10 , 365* 42+10 , 365* 43+11 , 365* 44+11 , 365* 45+11 , 365* 46+11 , 365* 47+12 , 365* 48+12 , 365* 49+12 ,
167	/2020:/ 365* 50+12 , 365* 51+13 , 365* 52+13 , 365* 53+13 , 365* 54+13 , 365* 55+14 , 365* 56+14 , 365* 57+14 , 365* 58+14 , 365* 59+15 ,
168	/2030:/ 365* 60+15 , 365* 61+15 , 365* 62+15 , 365* 63+16 , 365* 64+16 , 365* 65+16 , 365* 66+16 , 365* 67+17 , 365* 68+17 , 365* 69+17 ,
169	/2040:/ 365* 70+17 , 365* 71+18 , 365* 72+18 , 365* 73+18 , 365* 74+18 , 365* 75+19 , 365* 76+19 , 365* 77+19 , 365* 78+19 , 365* 79+20 ,
170	/2050:/ 365* 80+20 , 365* 81+20 , 365* 82+20 , 365* 83+21 , 365* 84+21 , 365* 85+21 , 365* 86+21 , 365* 87+22 , 365* 88+22 , 365* 89+22 ,
171	/2060:/ 365* 90+22 , 365* 91+23 , 365* 92+23 , 365* 93+23 , 365* 94+23 , 365* 95+24 , 365* 96+24 , 365* 97+24 , 365* 98+24 , 365* 99+25 ,
172	/2070:/ 365* 100+25 , 365* 101+25 , 365* 102+25 , 365* 103+26 , 365* 104+26 , 365* 105+26 , 365* 106+26 , 365* 107+27 , 365* 108+27 , 365* 109+27 ,
173	/2080:/ 365* 110+27 , 365* 111+28 , 365* 112+28 , 365* 113+28 , 365* 114+28 , 365* 115+29 , 365* 116+29 , 365* 117+29 , 365* 118+29 , 365* 119+30 ,
174	/2090:/ 365* 120+30 , 365* 121+30 , 365* 122+30 , 365* 123+31 , 365* 124+31 , 365* 125+31 , 365* 126+31 , 365* 127+32 , 365* 128+32 , 365* 129+32 ,
175	/2100:/ 365* 130+32 , 365* 131+32 , 365* 132+32 , 365* 133+32 , 365* 134+32 , 365* 135+33 , 365* 136+33 , 365* 137+33 , 365* 138+33 , 365* 139+34 ,
176	/2110:/ 365* 140+34 , 365* 141+34 , 365* 142+34 , 365* 143+35 , 365* 144+35 , 365* 145+35 , 365* 146+35 , 365* 147+36 , 365* 148+36 , 365* 149+36 ,
177	/2120:/ 365* 150+36 , 365* 151+37 , 365* 152+37 , 365* 153+37 , 365* 154+37 , 365* 155+38 , 365* 156+38 , 365* 157+38 , 365* 158+38 , 365* 159+39 ,
178	/2130:/ 365* 160+39 , 365* 161+39 , 365* 162+39 , 365* 163+40 , 365* 164+40 , 365* 165+40 , 365* 166+40 , 365* 167+41 , 365* 168+41 , 365* 169+41 ,
179	/2140:/ 365* 170+41 , 365* 171+42 , 365* 172+42 , 365* 173+42 , 365* 174+42 , 365* 175+43 , 365* 176+43 , 365* 177+43 , 365* 178+43 , 365* 179+44 ,
180	/2150:/ 365* 180+44 , 365* 181+44 , 365* 182+44 , 365* 183+45 , 365* 184+45 , 365* 185+45 , 365* 186+45 , 365* 187+46 , 365* 188+46 , 365* 189+46 ,
181	/2160:/ 365* 190+46 , 365* 191+47 , 365* 192+47 , 365* 193+47 , 365* 194+47 , 365* 195+48 , 365* 196+48 , 365* 197+48 , 365* 198+48 , 365* 199+49 ,
182	/2170:/ 365* 200+49 , 365* 201+49 , 365* 202+49 , 365* 203+50 , 365* 204+50 , 365* 205+50 , 365* 206+50 , 365* 207+51 , 365* 208+51 , 365* 209+51 ,
183	/2180:/ 365* 210+51 , 365* 211+52 , 365* 212+52 , 365* 213+52 , 365* 214+52 , 365* 215+53 , 365* 216+53 , 365* 217+53 , 365* 218+53 , 365* 219+54 ,
184	/2190:/ 365* 220+54 , 365* 221+54 , 365* 222+54 , 365* 223+55 , 365* 224+55 , 365* 225+55 , 365* 226+55 , 365* 227+56 , 365* 228+56 , 365* 229+56 ,
185	/2200:/ 365* 230+56 , 365* 231+56 , 365* 232+56 , 365* 233+56 , 365* 234+56 , 365* 235+57 , 365* 236+57 , 365* 237+57 , 365* 238+57 , 365* 239+58 ,
186	/2210:/ 365* 240+58 , 365* 241+58 , 365* 242+58 , 365* 243+59 , 365* 244+59 , 365* 245+59 , 365* 246+59 , 365* 247+60 , 365* 248+60 , 365* 249+60 ,
187	/2220:/ 365* 250+60 , 365* 251+61 , 365* 252+61 , 365* 253+61 , 365* 254+61 , 365* 255+62 , 365* 256+62 , 365* 257+62 , 365* 258+62 , 365* 259+63 ,
188	/2230:/ 365* 260+63 , 365* 261+63 , 365* 262+63 , 365* 263+64 , 365* 264+64 , 365* 265+64 , 365* 266+64 , 365* 267+65 , 365* 268+65 , 365* 269+65 ,
189	/2240:/ 365* 270+65 , 365* 271+66 , 365* 272+66 , 365* 273+66 , 365* 274+66 , 365* 275+67 , 365* 276+67 , 365* 277+67 , 365* 278+67 , 365* 279+68 ,
190	/2250:/ 365* 280+68 , 365* 281+68 , 365* 282+68 , 365* 283+69 , 365* 284+69 , 365* 285+69 , 365* 286+69 , 365* 287+70 , 365* 288+70 , 365* 289+70 ,
191	/2260:/ 365* 290+70 , 365* 291+71 , 365* 292+71 , 365* 293+71 , 365* 294+71 , 365* 295+72 , 365* 296+72 , 365* 297+72 , 365* 298+72 , 365* 299+73
192	};
193
194	/* generator code:
195	#include <stdio.h>
196	bool isLeapYear(int iYear)
197	{
198	return iYear % 4 == 0 && (iYear % 100 != 0 \|\| iYear % 400 == 0);
199	}
200	void printYear(int iYear, int iLeap)
201	{
202	if (!(iYear % 10))
203	printf("\n/" "%d:" "/", iYear + 1970);
204	printf(" 365*%4d+%-3d,", iYear, iLeap);
205	}
206	int main()
207	{
208	int iYear = 0;
209	int iLeap = 0;
210	while (iYear > -300)
211	iLeap -= isLeapYear(1970 + --iYear);
212	while (iYear < 300)
213	{
214	printYear(iYear, iLeap);
215	iLeap += isLeapYear(1970 + iYear++);
216	}
217	printf("\n");
218	return 0;
219	}
220	*/
221
222
223	/**
224	* Checks if a year is a leap year or not.
225	*
226	* @returns true if it's a leap year.
227	* @returns false if it's a common year.
228	* @param i32Year The year in question.
229	*/
230	DECLINLINE(bool) rtTimeIsLeapYear(int32_t i32Year)
231	{
232	return i32Year % 4 == 0
233	&& ( i32Year % 100 != 0
234	\|\| i32Year % 400 == 0);
235	}
236
237	/**
238	* Checks if a year is a leap year or not.
239	*
240	* @returns true if it's a leap year.
241	* @returns false if it's a common year.
242	* @param i32Year The year in question.
243	*/
244	RTDECL(bool) RTTimeIsLeapYear(int32_t i32Year)
245	{
246	return rtTimeIsLeapYear(i32Year);
247	}
248
249
250	/**
251	* Explodes a time spec (UTC).
252	*
253	* @returns pTime.
254	* @param pTime Where to store the exploded time.
255	* @param pTimeSpec The time spec to exploded.
256	*/
257	RTDECL(PRTTIME) RTTimeExplode(PRTTIME pTime, PCRTTIMESPEC pTimeSpec)
258	{
259	AssertMsg(VALID_PTR(pTime), ("%p\n", pTime));
260	AssertMsg(VALID_PTR(pTimeSpec), ("%p\n", pTime));
261
262	/*
263	* The simple stuff first.
264	*/
265	pTime->fFlags = RTTIME_FLAGS_TYPE_UTC;
266	int64_t i64Div = pTimeSpec->i64NanosecondsRelativeToUnixEpoch;
267	int32_t i32Rem = (int32_t)(i64Div % 1000000000);
268	i64Div /= 1000000000;
269	if (i32Rem < 0)
270	{
271	i32Rem += 1000000000;
272	i64Div--;
273	}
274	pTime->u32Nanosecond = i32Rem;
275
276	/* second */
277	i32Rem = (int32_t)(i64Div % 60);
278	i64Div /= 60;
279	if (i32Rem < 0)
280	{
281	i32Rem += 60;
282	i64Div--;
283	}
284	pTime->u8Second = i32Rem;
285
286	/* minute */
287	int32_t i32Div = (int32_t)i64Div; /* 60,000,000,000 > 33bit, so 31bit suffices. */
288	i32Rem = i32Div % 60;
289	i32Div /= 60;
290	if (i32Rem < 0)
291	{
292	i32Rem += 60;
293	i32Div--;
294	}
295	pTime->u8Minute = i32Rem;
296
297	/* hour */
298	i32Rem = i32Div % 24;
299	i32Div /= 24; /* days relative to 1970-01-01 */
300	if (i32Rem < 0)
301	{
302	i32Rem += 24;
303	i32Div--;
304	}
305	pTime->u8Hour = i32Rem;
306
307	/* weekday - 1970-01-01 was a Thursday (3) */
308	pTime->u8WeekDay = ((int)(i32Div % 7) + 3 + 7) % 7;
309
310	/*
311	* We've now got a number of days relative to 1970-01-01.
312	* To get the correct year number we have to mess with leap years. Fortunatly,
313	* the represenation we've got only supports a few hundred years, so we can
314	* generate a table and perform a simple two way search from the modulus 365 derived.
315	*/
316	unsigned iYear = OFF_YEAR_IDX_EPOCH + i32Div / 365;
317	while (g_aoffYear[iYear + 1] <= i32Div)
318	iYear++;
319	while (g_aoffYear[iYear] > i32Div)
320	iYear--;
321	pTime->i32Year = iYear + OFF_YEAR_IDX_0_YEAR;
322	i32Div -= g_aoffYear[iYear];
323	pTime->u16YearDay = i32Div + 1;
324
325	/*
326	* Figuring out the month is done in a manner similar to the year, only here we
327	* ensure that the index is matching or too small.
328	*/
329	const uint16_t *paiDayOfYear;
330	if (rtTimeIsLeapYear(pTime->i32Year))
331	{
332	pTime->fFlags \|= RTTIME_FLAGS_LEAP_YEAR;
333	paiDayOfYear = &g_aiDayOfYearLeap[0];
334	}
335	else
336	{
337	pTime->fFlags \|= RTTIME_FLAGS_COMMON_YEAR;
338	paiDayOfYear = &g_aiDayOfYear[0];
339	}
340	int iMonth = i32Div / 32;
341	i32Div++;
342	while (paiDayOfYear[iMonth + 1] <= i32Div)
343	iMonth++;
344	pTime->u8Month = iMonth + 1;
345	i32Div -= paiDayOfYear[iMonth];
346	pTime->u8MonthDay = i32Div + 1;
347
348	/* This is for UTC timespecs, so, no offset. */
349	pTime->offUTC = 0;
350
351	return pTime;
352	}
353
354
355	/**
356	* Implodes exploded time to a time spec (UTC).
357	*
358	* @returns pTime on success.
359	* @returns NULL if the pTime data is invalid.
360	* @param pTimeSpec Where to store the imploded UTC time.
361	* If pTime specifies a time which outside the range, maximum or
362	* minimum values will be returned.
363	* @param pTime Pointer to the exploded time to implode.
364	* The fields u8Month, u8WeekDay and u8MonthDay are not used,
365	* and all the other fields are expected to be within their
366	* bounds. Use RTTimeNormalize() to calculate u16YearDay and
367	* normalize the ranges of the fields.
368	*/
369	RTDECL(PRTTIMESPEC) RTTimeImplode(PRTTIMESPEC pTimeSpec, PCRTTIME pTime)
370	{
371	/*
372	* Validate input.
373	*/
374	AssertReturn(VALID_PTR(pTimeSpec), NULL);
375	AssertReturn(VALID_PTR(pTime), NULL);
376	AssertReturn(pTime->u32Nanosecond < 1000000000, NULL);
377	AssertReturn(pTime->u8Second < 60, NULL);
378	AssertReturn(pTime->u8Minute < 60, NULL);
379	AssertReturn(pTime->u8Hour < 24, NULL);
380	AssertReturn(pTime->u16YearDay >= 1, NULL);
381	AssertReturn(pTime->u16YearDay <= (rtTimeIsLeapYear(pTime->i32Year) ? 366 : 365), NULL);
382	AssertMsgReturn(pTime->i32Year <= RTTIME_MAX_YEAR && pTime->i32Year >= RTTIME_MIN_YEAR, ("%RI32\n", pTime->i32Year), NULL);
383
384	/*
385	* Do the conversion to nanoseconds.
386	*/
387	int32_t i32Days = g_aoffYear[pTime->i32Year - OFF_YEAR_IDX_0_YEAR]
388	+ pTime->u16YearDay - 1;
389	AssertMsgReturn(i32Days <= RTTIME_MAX_DAY && i32Days >= RTTIME_MIN_DAY, ("%RI32\n", i32Days), NULL);
390
391	uint32_t u32Secs = pTime->u8Second
392	+ pTime->u8Minute * 60
393	+ pTime->u8Hour * 3600;
394	int64_t i64Nanos = (uint64_t)pTime->u32Nanosecond
395	+ u32Secs * UINT64_C(1000000000);
396	AssertMsgReturn(i32Days != RTTIME_MAX_DAY \|\| i64Nanos <= RTTIME_MAX_DAY_NANO, ("%RI64\n", i64Nanos), NULL);
397	AssertMsgReturn(i32Days != RTTIME_MIN_DAY \|\| i64Nanos >= RTTIME_MIN_DAY_NANO, ("%RI64\n", i64Nanos), NULL);
398
399	i64Nanos += i32Days * UINT64_C(86400000000000);
400
401	pTimeSpec->i64NanosecondsRelativeToUnixEpoch = i64Nanos;
402	return pTimeSpec;
403	}
404
405
406	/**
407	* Internal worker for RTTimeNormalize and RTTimeLocalNormalize.
408	* It doesn't adjust the UCT offset but leaves that for RTTimeLocalNormalize.
409	*/
410	PRTTIME rtTimeNormalizeInternal(PRTTIME pTime)
411	{
412	/*
413	* Fix the YearDay and Month/MonthDay.
414	*/
415	bool fLeapYear = rtTimeIsLeapYear(pTime->i32Year);
416	if (!pTime->u16YearDay)
417	{
418	/*
419	* The Month+MonthDay must present, overflow adjust them and calc the year day.
420	*/
421	AssertMsgReturn( pTime->u8Month
422	&& pTime->u8MonthDay,
423	("date=%d-%d-%d\n", pTime->i32Year, pTime->u8Month, pTime->u8MonthDay),
424	NULL);
425	while (pTime->u8Month > 12)
426	{
427	pTime->u8Month -= 12;
428	pTime->i32Year++;
429	fLeapYear = rtTimeIsLeapYear(pTime->i32Year);
430	pTime->fFlags &= ~(RTTIME_FLAGS_COMMON_YEAR \| RTTIME_FLAGS_LEAP_YEAR);
431	}
432
433	for (;;)
434	{
435	unsigned cDaysInMonth = fLeapYear
436	? g_acDaysInMonthsLeap[pTime->u8Month - 1]
437	: g_acDaysInMonthsLeap[pTime->u8Month - 1];
438	if (pTime->u8MonthDay <= cDaysInMonth)
439	break;
440	pTime->u8MonthDay -= cDaysInMonth;
441	if (pTime->u8Month != 12)
442	pTime->u8Month++;
443	else
444	{
445	pTime->u8Month = 1;
446	pTime->i32Year++;
447	fLeapYear = rtTimeIsLeapYear(pTime->i32Year);
448	pTime->fFlags &= ~(RTTIME_FLAGS_COMMON_YEAR \| RTTIME_FLAGS_LEAP_YEAR);
449	}
450	}
451
452	pTime->u16YearDay = pTime->u8MonthDay - 1
453	+ (fLeapYear
454	? g_aiDayOfYearLeap[pTime->u8Month - 1]
455	: g_aiDayOfYear[pTime->u8Month - 1]);
456	}
457	else
458	{
459	/*
460	* Are both YearDay and Month/MonthDay valid?
461	* Check that they don't overflow and match, if not use YearDay (simpler).
462	*/
463	bool fRecalc = true;
464	if ( pTime->u8Month
465	&& pTime->u8MonthDay)
466	{
467	do
468	{
469	/* If you change one, zero the other to make clear what you mean. */
470	AssertBreak(pTime->u8Month <= 12);
471	AssertBreak(pTime->u8MonthDay <= (fLeapYear
472	? g_acDaysInMonthsLeap[pTime->u8Month - 1]
473	: g_acDaysInMonths[pTime->u8Month - 1]));
474	uint16_t u16YearDay = pTime->u8MonthDay - 1
475	+ (fLeapYear
476	? g_aiDayOfYearLeap[pTime->u8Month - 1]
477	: g_aiDayOfYear[pTime->u8Month - 1]);
478	AssertBreak(u16YearDay == pTime->u16YearDay);
479	fRecalc = false;
480	} while (0);
481	}
482	if (fRecalc)
483	{
484	/* overflow adjust YearDay */
485	while (pTime->u16YearDay > (fLeapYear ? 366 : 365))
486	{
487	pTime->u16YearDay -= fLeapYear ? 366 : 365;
488	pTime->i32Year++;
489	fLeapYear = rtTimeIsLeapYear(pTime->i32Year);
490	pTime->fFlags &= ~(RTTIME_FLAGS_COMMON_YEAR \| RTTIME_FLAGS_LEAP_YEAR);
491	}
492
493	/* calc Month and MonthDay */
494	const uint16_t *paiDayOfYear = fLeapYear
495	? &g_aiDayOfYearLeap[0]
496	: &g_aiDayOfYear[0];
497	pTime->u8Month = 1;
498	while (pTime->u16YearDay > paiDayOfYear[pTime->u8Month])
499	pTime->u8Month++;
500	Assert(pTime->u8Month >= 1 && pTime->u8Month <= 12);
501	pTime->u8MonthDay = pTime->u16YearDay - paiDayOfYear[pTime->u8Month - 1] + 1;
502	}
503	}
504
505	/*
506	* Fixup time overflows.
507	* Use unsigned int values internally to avoid overflows.
508	*/
509	unsigned uSecond = pTime->u8Second;
510	unsigned uMinute = pTime->u8Minute;
511	unsigned uHour = pTime->u8Hour;
512
513	while (pTime->u32Nanosecond >= 1000000000)
514	{
515	pTime->u32Nanosecond -= 1000000000;
516	uSecond++;
517	}
518
519	while (uSecond >= 60)
520	{
521	uSecond -= 60;
522	uMinute++;
523	}
524
525	while (uMinute >= 60)
526	{
527	uMinute -= 60;
528	uHour++;
529	}
530
531	while (uHour >= 24)
532	{
533	uHour -= 24;
534
535	/* This is really a RTTimeIncDay kind of thing... */
536	if (pTime->u16YearDay + 1 != (fLeapYear ? g_aiDayOfYearLeap[pTime->u8Month] : g_aiDayOfYear[pTime->u8Month]))
537	{
538	pTime->u16YearDay++;
539	pTime->u8MonthDay++;
540	}
541	else if (pTime->u8Month != 12)
542	{
543	pTime->u16YearDay++;
544	pTime->u8Month++;
545	pTime->u8MonthDay = 1;
546	}
547	else
548	{
549	pTime->i32Year++;
550	fLeapYear = rtTimeIsLeapYear(pTime->i32Year);
551	pTime->fFlags &= ~(RTTIME_FLAGS_COMMON_YEAR \| RTTIME_FLAGS_LEAP_YEAR);
552	pTime->u16YearDay = 1;
553	pTime->u8Month = 1;
554	pTime->u8MonthDay = 1;
555	}
556	}
557
558	pTime->u8Second = uSecond;
559	pTime->u8Minute = uMinute;
560	pTime->u8Hour = uHour;
561
562	/*
563	* Correct the leap year flag.
564	* Assert if it's wrong, but ignore if unset.
565	*/
566	if (fLeapYear)
567	{
568	Assert(!(pTime->fFlags & RTTIME_FLAGS_COMMON_YEAR));
569	pTime->fFlags &= ~RTTIME_FLAGS_COMMON_YEAR;
570	pTime->fFlags \|= RTTIME_FLAGS_LEAP_YEAR;
571	}
572	else
573	{
574	Assert(!(pTime->fFlags & RTTIME_FLAGS_LEAP_YEAR));
575	pTime->fFlags &= ~RTTIME_FLAGS_LEAP_YEAR;
576	pTime->fFlags \|= RTTIME_FLAGS_COMMON_YEAR;
577	}
578
579
580	/*
581	* Calc week day.
582	*
583	* 1970-01-01 was a Thursday (3), so find the number of days relative to
584	* that point. We use the table when possible and a slow+stupid+brute-force
585	* algorithm for points outside it. Feel free to optimize the latter by
586	* using some clever formula.
587	*/
588	if ( pTime->i32Year >= OFF_YEAR_IDX_0_YEAR
589	&& pTime->i32Year < OFF_YEAR_IDX_0_YEAR + (int32_t)RT_ELEMENTS(g_aoffYear))
590	{
591	int32_t offDays = g_aoffYear[pTime->i32Year - OFF_YEAR_IDX_0_YEAR]
592	+ pTime->u16YearDay -1;
593	pTime->u8WeekDay = ((offDays % 7) + 3 + 7) % 7;
594	}
595	else
596	{
597	int32_t i32Year = pTime->i32Year;
598	if (i32Year >= 1970)
599	{
600	uint64_t offDays = pTime->u16YearDay - 1;
601	while (--i32Year >= 1970)
602	offDays += rtTimeIsLeapYear(i32Year) ? 366 : 365;
603	pTime->u8WeekDay = (uint8_t)((offDays + 3) % 7);
604	}
605	else
606	{
607	int64_t offDays = (fLeapYear ? -366 - 1 : -365 - 1) + pTime->u16YearDay;
608	while (++i32Year < 1970)
609	offDays -= rtTimeIsLeapYear(i32Year) ? 366 : 365;
610	pTime->u8WeekDay = ((int)(offDays % 7) + 3 + 7) % 7;
611	}
612	}
613	return pTime;
614	}
615
616
617	/**
618	* Normalizes the fields of a time structure.
619	*
620	* It is possible to calculate year-day from month/day and vice
621	* versa. If you adjust any of these, make sure to zero the
622	* other so you make it clear which of the fields to use. If
623	* it's ambiguous, the year-day field is used (and you get
624	* assertions in debug builds).
625	*
626	* All the time fields and the year-day or month/day fields will
627	* be adjusted for overflows. (Since all fields are unsigned, there
628	* is no underflows.) It is possible to exploit this for simple
629	* date math, though the recommended way of doing that to implode
630	* the time into a timespec and do the math on that.
631	*
632	* @returns pTime on success.
633	* @returns NULL if the data is invalid.
634	*
635	* @param pTime The time structure to normalize.
636	*
637	* @remarks This function doesn't work with local time, only with UTC time.
638	*/
639	RTDECL(PRTTIME) RTTimeNormalize(PRTTIME pTime)
640	{
641	/*
642	* Validate that we've got the minium of stuff handy.
643	*/
644	AssertReturn(VALID_PTR(pTime), NULL);
645	AssertMsgReturn(!(pTime->fFlags & ~RTTIME_FLAGS_MASK), ("%#x\n", pTime->fFlags), NULL);
646	AssertMsgReturn((pTime->fFlags & RTTIME_FLAGS_TYPE_MASK) != RTTIME_FLAGS_TYPE_LOCAL, ("Use RTTimeLocalNormalize!\n"), NULL);
647	AssertMsgReturn(pTime->offUTC == 0, ("%d; Use RTTimeLocalNormalize!\n", pTime->offUTC), NULL);
648
649	pTime = rtTimeNormalizeInternal(pTime);
650	if (pTime)
651	pTime->fFlags \|= RTTIME_FLAGS_TYPE_UTC;
652	return pTime;
653	}
654
655
656	/**
657	* Converts a time spec to a ISO date string.
658	*
659	* @returns psz on success.
660	* @returns NULL on buffer underflow.
661	* @param pTime The time. Caller should've normalized this.
662	* @param psz Where to store the string.
663	* @param cb The size of the buffer.
664	*/
665	RTDECL(char ) RTTimeToString(PCRTTIME pTime, char psz, size_t cb)
666	{
667	/* (Default to UTC if not specified) */
668	if ( (pTime->fFlags & RTTIME_FLAGS_TYPE_MASK) == RTTIME_FLAGS_TYPE_LOCAL
669	&& pTime->offUTC)
670	{
671	Assert(pTime->offUTC <= 840 && pTime->offUTC >= -840);
672	int32_t offUTCHour = pTime->offUTC / 60;
673	int32_t offUTCMinute = pTime->offUTC % 60;
674	char chSign;
675	if (pTime->offUTC >= 0)
676	chSign = '+';
677	else
678	{
679	chSign = '-';
680	offUTCMinute = -offUTCMinute;
681	offUTCHour = -offUTCHour;
682	}
683	size_t cch = RTStrPrintf(psz, cb,
684	"%RI32-%02u-%02uT%02u:%02u:%02u.%09RU32%c%02%02",
685	pTime->i32Year, pTime->u8Month, pTime->u8MonthDay,
686	pTime->u8Hour, pTime->u8Minute, pTime->u8Second, pTime->u32Nanosecond,
687	chSign, offUTCHour, offUTCMinute);
688	if ( cch <= 15
689	\|\| psz[cch - 5] != chSign)
690	return NULL;
691	}
692	else
693	{
694	size_t cch = RTStrPrintf(psz, cb, "%RI32-%02u-%02uT%02u:%02u:%02u.%09RU32Z",
695	pTime->i32Year, pTime->u8Month, pTime->u8MonthDay,
696	pTime->u8Hour, pTime->u8Minute, pTime->u8Second, pTime->u32Nanosecond);
697	if ( cch <= 15
698	\|\| psz[cch - 1] != 'Z')
699	return NULL;
700	}
701	return psz;
702	}
703
704
705	/**
706	* Converts a time spec to a ISO date string.
707	*
708	* @returns psz on success.
709	* @returns NULL on buffer underflow.
710	* @param pTime The time spec.
711	* @param psz Where to store the string.
712	* @param cb The size of the buffer.
713	*/
714	RTDECL(char ) RTTimeSpecToString(PCRTTIMESPEC pTime, char psz, size_t cb)
715	{
716	RTTIME Time;
717	return RTTimeToString(RTTimeExplode(&Time, pTime), psz, cb);
718	}
719

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source: vbox/trunk/src/VBox/Runtime/common/time/time.cpp@ 18096

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