1/*
2 * Copyright (C) 1999-2000 Harri Porten (porten@kde.org)
3 * Copyright (C) 2006, 2007 Apple Inc. All rights reserved.
4 * Copyright (C) 2009 Google Inc. All rights reserved.
5 *
6 * Version: MPL 1.1/GPL 2.0/LGPL 2.1
7 *
8 * The contents of this file are subject to the Mozilla Public License Version
9 * 1.1 (the "License"); you may not use this file except in compliance with
10 * the License. You may obtain a copy of the License at
11 * http://www.mozilla.org/MPL/
12 *
13 * Software distributed under the License is distributed on an "AS IS" basis,
14 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
15 * for the specific language governing rights and limitations under the
16 * License.
17 *
18 * The Original Code is Mozilla Communicator client code, released
19 * March 31, 1998.
20 *
21 * The Initial Developer of the Original Code is
22 * Netscape Communications Corporation.
23 * Portions created by the Initial Developer are Copyright (C) 1998
24 * the Initial Developer. All Rights Reserved.
25 *
26 * Contributor(s):
27 *
28 * Alternatively, the contents of this file may be used under the terms of
29 * either of the GNU General Public License Version 2 or later (the "GPL"),
30 * or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
31 * in which case the provisions of the GPL or the LGPL are applicable instead
32 * of those above. If you wish to allow use of your version of this file only
33 * under the terms of either the GPL or the LGPL, and not to allow others to
34 * use your version of this file under the terms of the MPL, indicate your
35 * decision by deleting the provisions above and replace them with the notice
36 * and other provisions required by the GPL or the LGPL. If you do not delete
37 * the provisions above, a recipient may use your version of this file under
38 * the terms of any one of the MPL, the GPL or the LGPL.
39 *
40 */
41
42#ifndef DateMath_h
43#define DateMath_h
44
45#include <math.h>
46#include <string.h>
47#include <time.h>
48#include <wtf/CurrentTime.h>
49#include <wtf/Noncopyable.h>
50#include <wtf/UnusedParam.h>
51
52namespace WTF {
53void initializeDates();
54int equivalentYearForDST(int year);
55
56// Not really math related, but this is currently the only shared place to put these.
57double parseDateFromNullTerminatedCharacters(const char* dateString);
58double timeClip(double);
59
60inline double jsCurrentTime()
61{
62    // JavaScript doesn't recognize fractions of a millisecond.
63    return floor(WTF::currentTimeMS());
64}
65
66const char * const weekdayName[7] = { "Mon", "Tue", "Wed", "Thu", "Fri", "Sat", "Sun" };
67const char * const monthName[12] = { "Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sep", "Oct", "Nov", "Dec" };
68
69const double hoursPerDay = 24.0;
70const double minutesPerHour = 60.0;
71const double secondsPerHour = 60.0 * 60.0;
72const double secondsPerMinute = 60.0;
73const double msPerSecond = 1000.0;
74const double msPerMinute = 60.0 * 1000.0;
75const double msPerHour = 60.0 * 60.0 * 1000.0;
76const double msPerDay = 24.0 * 60.0 * 60.0 * 1000.0;
77const double msPerMonth = 2592000000.0;
78
79// Returns the number of days from 1970-01-01 to the specified date.
80double dateToDaysFrom1970(int year, int month, int day);
81int msToYear(double ms);
82int dayInYear(double ms, int year);
83int monthFromDayInYear(int dayInYear, bool leapYear);
84int dayInMonthFromDayInYear(int dayInYear, bool leapYear);
85
86} // namespace WTF
87
88using WTF::dateToDaysFrom1970;
89using WTF::dayInMonthFromDayInYear;
90using WTF::dayInYear;
91using WTF::minutesPerHour;
92using WTF::monthFromDayInYear;
93using WTF::msPerDay;
94using WTF::msPerSecond;
95using WTF::msToYear;
96using WTF::secondsPerMinute;
97
98#if USE(JSC)
99namespace JSC {
100class ExecState;
101struct GregorianDateTime;
102
103void msToGregorianDateTime(ExecState*, double, bool outputIsUTC, GregorianDateTime&);
104double gregorianDateTimeToMS(ExecState*, const GregorianDateTime&, double, bool inputIsUTC);
105double getUTCOffset(ExecState*);
106double parseDateFromNullTerminatedCharacters(ExecState*, const char* dateString);
107
108// Intentionally overridding the default tm of the system.
109// The members of tm differ on various operating systems.
110struct GregorianDateTime : Noncopyable {
111    GregorianDateTime()
112        : second(0)
113        , minute(0)
114        , hour(0)
115        , weekDay(0)
116        , monthDay(0)
117        , yearDay(0)
118        , month(0)
119        , year(0)
120        , isDST(0)
121        , utcOffset(0)
122        , timeZone(0)
123    {
124    }
125
126    ~GregorianDateTime()
127    {
128        delete [] timeZone;
129    }
130
131    GregorianDateTime(ExecState* exec, const tm& inTm)
132        : second(inTm.tm_sec)
133        , minute(inTm.tm_min)
134        , hour(inTm.tm_hour)
135        , weekDay(inTm.tm_wday)
136        , monthDay(inTm.tm_mday)
137        , yearDay(inTm.tm_yday)
138        , month(inTm.tm_mon)
139        , year(inTm.tm_year)
140        , isDST(inTm.tm_isdst)
141    {
142        UNUSED_PARAM(exec);
143#if HAVE(TM_GMTOFF)
144        utcOffset = static_cast<int>(inTm.tm_gmtoff);
145#else
146        utcOffset = static_cast<int>(getUTCOffset(exec) / WTF::msPerSecond + (isDST ? WTF::secondsPerHour : 0));
147#endif
148
149#if HAVE(TM_ZONE)
150        int inZoneSize = strlen(inTm.tm_zone) + 1;
151        timeZone = new char[inZoneSize];
152        strncpy(timeZone, inTm.tm_zone, inZoneSize);
153#else
154        timeZone = 0;
155#endif
156    }
157
158    operator tm() const
159    {
160        tm ret;
161        memset(&ret, 0, sizeof(ret));
162
163        ret.tm_sec   =  second;
164        ret.tm_min   =  minute;
165        ret.tm_hour  =  hour;
166        ret.tm_wday  =  weekDay;
167        ret.tm_mday  =  monthDay;
168        ret.tm_yday  =  yearDay;
169        ret.tm_mon   =  month;
170        ret.tm_year  =  year;
171        ret.tm_isdst =  isDST;
172
173#if HAVE(TM_GMTOFF)
174        ret.tm_gmtoff = static_cast<long>(utcOffset);
175#endif
176#if HAVE(TM_ZONE)
177        ret.tm_zone = timeZone;
178#endif
179
180        return ret;
181    }
182
183    void copyFrom(const GregorianDateTime& rhs)
184    {
185        second = rhs.second;
186        minute = rhs.minute;
187        hour = rhs.hour;
188        weekDay = rhs.weekDay;
189        monthDay = rhs.monthDay;
190        yearDay = rhs.yearDay;
191        month = rhs.month;
192        year = rhs.year;
193        isDST = rhs.isDST;
194        utcOffset = rhs.utcOffset;
195        if (rhs.timeZone) {
196            int inZoneSize = strlen(rhs.timeZone) + 1;
197            timeZone = new char[inZoneSize];
198            strncpy(timeZone, rhs.timeZone, inZoneSize);
199        } else
200            timeZone = 0;
201    }
202
203    int second;
204    int minute;
205    int hour;
206    int weekDay;
207    int monthDay;
208    int yearDay;
209    int month;
210    int year;
211    int isDST;
212    int utcOffset;
213    char* timeZone;
214};
215
216static inline int gmtoffset(const GregorianDateTime& t)
217{
218    return t.utcOffset;
219}
220} // namespace JSC
221#endif // USE(JSC)
222
223#endif // DateMath_h
224