summaryrefslogtreecommitdiffstats
path: root/Source/WTF/wtf/DateMath.h
blob: 0e1f449e61c596668e1150552ed5ac525c8c6b61 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
/*
 * Copyright (C) 1999-2000 Harri Porten (porten@kde.org)
 * Copyright (C) 2006, 2007 Apple Inc. All rights reserved.
 * Copyright (C) 2009 Google Inc. All rights reserved.
 * Copyright (C) 2010 Research In Motion Limited. All rights reserved.
 *
 * Version: MPL 1.1/GPL 2.0/LGPL 2.1
 *
 * The contents of this file are subject to the Mozilla Public License Version
 * 1.1 (the "License"); you may not use this file except in compliance with
 * the License. You may obtain a copy of the License at
 * http://www.mozilla.org/MPL/
 *
 * Software distributed under the License is distributed on an "AS IS" basis,
 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
 * for the specific language governing rights and limitations under the
 * License.
 *
 * The Original Code is Mozilla Communicator client code, released
 * March 31, 1998.
 *
 * The Initial Developer of the Original Code is
 * Netscape Communications Corporation.
 * Portions created by the Initial Developer are Copyright (C) 1998
 * the Initial Developer. All Rights Reserved.
 *
 * Contributor(s):
 *
 * Alternatively, the contents of this file may be used under the terms of
 * either of the GNU General Public License Version 2 or later (the "GPL"),
 * or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
 * in which case the provisions of the GPL or the LGPL are applicable instead
 * of those above. If you wish to allow use of your version of this file only
 * under the terms of either the GPL or the LGPL, and not to allow others to
 * use your version of this file under the terms of the MPL, indicate your
 * decision by deleting the provisions above and replace them with the notice
 * and other provisions required by the GPL or the LGPL. If you do not delete
 * the provisions above, a recipient may use your version of this file under
 * the terms of any one of the MPL, the GPL or the LGPL.
 *
 */

#ifndef DateMath_h
#define DateMath_h

#include <math.h>
#include <stdint.h>
#include <string.h>
#include <time.h>
#include <wtf/CurrentTime.h>
#include <wtf/Noncopyable.h>
#include <wtf/text/WTFString.h>

namespace WTF {

enum TimeType {
    UTCTime = 0,
    LocalTime
};

struct LocalTimeOffset {
    LocalTimeOffset()
        : isDST(false)
        , offset(0)
    {
    }

    LocalTimeOffset(bool isDST, int offset)
        : isDST(isDST)
        , offset(offset)
    {
    }

    bool operator==(const LocalTimeOffset& other)
    {
        return isDST == other.isDST && offset == other.offset;
    }

    bool operator!=(const LocalTimeOffset& other)
    {
        return isDST != other.isDST || offset != other.offset;
    }

    bool isDST;
    int offset;
};

void initializeDates();
int equivalentYearForDST(int year);

// Not really math related, but this is currently the only shared place to put these.
WTF_EXPORT_PRIVATE double parseES5DateFromNullTerminatedCharacters(const char* dateString);
WTF_EXPORT_PRIVATE double parseDateFromNullTerminatedCharacters(const char* dateString);
WTF_EXPORT_PRIVATE double parseDateFromNullTerminatedCharacters(const char* dateString, bool& haveTZ, int& offset);
WTF_EXPORT_PRIVATE double timeClip(double);
// dayOfWeek: [0, 6] 0 being Monday, day: [1, 31], month: [0, 11], year: ex: 2011, hours: [0, 23], minutes: [0, 59], seconds: [0, 59], utcOffset: [-720,720]. 
WTF_EXPORT_PRIVATE String makeRFC2822DateString(unsigned dayOfWeek, unsigned day, unsigned month, unsigned year, unsigned hours, unsigned minutes, unsigned seconds, int utcOffset);

inline double jsCurrentTime()
{
    // JavaScript doesn't recognize fractions of a millisecond.
    return floor(WTF::currentTimeMS());
}

const char* const weekdayName[7] = { "Mon", "Tue", "Wed", "Thu", "Fri", "Sat", "Sun" };
const char* const monthName[12] = { "Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sep", "Oct", "Nov", "Dec" };
const char* const monthFullName[12] = { "January", "February", "March", "April", "May", "June", "July", "August", "September", "October", "November", "December" };

const double hoursPerDay = 24.0;
const double minutesPerHour = 60.0;
const double secondsPerMinute = 60.0;
const double msPerSecond = 1000.0;
const double msPerMonth = 2592000000.0;
const double secondsPerHour = secondsPerMinute * minutesPerHour;
const double secondsPerDay = secondsPerHour * hoursPerDay;
const double msPerMinute = msPerSecond * secondsPerMinute;
const double msPerHour = msPerSecond * secondsPerHour;
const double msPerDay = msPerSecond * secondsPerDay;

WTF_EXPORT_PRIVATE bool isLeapYear(int year);

// Returns the number of days from 1970-01-01 to the specified date.
WTF_EXPORT_PRIVATE double dateToDaysFrom1970(int year, int month, int day);
WTF_EXPORT_PRIVATE int msToYear(double ms);
WTF_EXPORT_PRIVATE double msToDays(double ms);
WTF_EXPORT_PRIVATE int msToMinutes(double ms);
WTF_EXPORT_PRIVATE int msToHours(double ms);
WTF_EXPORT_PRIVATE int dayInYear(int year, int month, int day);
WTF_EXPORT_PRIVATE int dayInYear(double ms, int year);
WTF_EXPORT_PRIVATE int monthFromDayInYear(int dayInYear, bool leapYear);
WTF_EXPORT_PRIVATE int dayInMonthFromDayInYear(int dayInYear, bool leapYear);

// Returns combined offset in millisecond (UTC + DST).
WTF_EXPORT_PRIVATE LocalTimeOffset calculateLocalTimeOffset(double utcInMilliseconds, TimeType = UTCTime);

} // namespace WTF

using WTF::isLeapYear;
using WTF::dateToDaysFrom1970;
using WTF::dayInMonthFromDayInYear;
using WTF::dayInYear;
using WTF::minutesPerHour;
using WTF::monthFromDayInYear;
using WTF::msPerDay;
using WTF::msPerHour;
using WTF::msPerMinute;
using WTF::msPerSecond;
using WTF::msToYear;
using WTF::msToDays;
using WTF::msToMinutes;
using WTF::msToHours;
using WTF::secondsPerDay;
using WTF::secondsPerMinute;
using WTF::parseDateFromNullTerminatedCharacters;
using WTF::makeRFC2822DateString;
using WTF::LocalTimeOffset;
using WTF::calculateLocalTimeOffset;

#endif // DateMath_h