#include "wx/log.h"
#endif // WX_PRECOMP
+#include "wx/thread.h"
+
+#define wxDEFINE_TIME_CONSTANTS
+
#include "wx/datetime.h"
+// ----------------------------------------------------------------------------
+// constants
+// ----------------------------------------------------------------------------
+
+// some trivial ones
+static const int MONTHS_IN_YEAR = 12;
+
+static const int SECONDS_IN_MINUTE = 60;
+
+static const long SECONDS_PER_DAY = 86400l;
+
+static const long MILLISECONDS_PER_DAY = 86400000l;
+
+// this is the integral part of JDN of the midnight of Jan 1, 1970
+// (i.e. JDN(Jan 1, 1970) = 2440587.5)
+static const int EPOCH_JDN = 2440587;
+
+// ----------------------------------------------------------------------------
+// globals
+// ----------------------------------------------------------------------------
+
+// a critical section is needed to protect GetTimeZone() static
+// variable in MT case
+#ifdef wxUSE_THREADS
+ wxCriticalSection gs_critsectTimezone;
+#endif // wxUSE_THREADS
+
+// ----------------------------------------------------------------------------
+// private functions
+// ----------------------------------------------------------------------------
+
+// get the number of days in the given month of the given year
+static inline
+wxDateTime::wxDateTime_t GetNumOfDaysInMonth(int year, wxDateTime::Month month)
+{
+ // the number of days in month in Julian/Gregorian calendar: the first line
+ // is for normal years, the second one is for the leap ones
+ static wxDateTime::wxDateTime_t daysInMonth[2][MONTHS_IN_YEAR] =
+ {
+ { 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 },
+ { 31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 }
+ };
+
+ return daysInMonth[wxDateTime::IsLeapYear(year)][month];
+}
+
+// ensure that the timezone variable is set by calling localtime
+static int GetTimeZone()
+{
+ // set to TRUE when the timezone is set
+ static bool s_timezoneSet = FALSE;
+
+ wxCRIT_SECT_LOCKER(lock, gs_critsectTimezone);
+
+ if ( !s_timezoneSet )
+ {
+ // just call localtime() instead of figurin out whether this system
+ // supports tzset(), _tzset() or something else
+ time_t t;
+ (void)localtime(&t);
+
+ s_timezoneSet = TRUE;
+ }
+
+ return (int)timezone;
+}
+
+// return the integral part of the JDN for the midnight of the given date (to
+// get the real JDN you need to add 0.5, this is, in fact, JDN of the noon of
+// the previous day)
+static long GetTruncatedJDN(wxDateTime::wxDateTime_t day,
+ wxDateTime::Month mon,
+ int year)
+{
+ // CREDIT: the algorithm was taken from Peter Baum's home page
+
+ // the algorithm assumes Jan == 1
+ int month = mon + 1;
+
+ // we want the leap day (Feb 29) be at the end of the year, so we count
+ // March as the first month
+ if ( month < wxDateTime::Mar + 1 )
+ {
+ month += MONTHS_IN_YEAR;
+ year--;
+ }
+
+ // this table contains the number of the days before the 1st of the each
+ // month (in a non leap year) with the third value corresponding to March
+ // (and the last one to February)
+ static const int monthOffsets[14] =
+ {
+ 0, 31, 61, 92, 122, 153, 184, 214, 245, 275, 306
+ };
+
+ // and now add contributions of all terms together to get the result (you'd
+ // better see the Web page for the description if you want to understand
+ // why it works (if it does :-))
+ return day +
+ // linear approximation for months
+ monthOffsets[month - (wxDateTime::Mar + 1)] +
+ // the year contribution
+ 365*year + year/4 - year/100 + year/400 +
+ // 1721119.5 is the JDN of the midnight of Mar 1, year 0
+ 1721118;
+}
+
+// this function is a wrapper around strftime(3)
+static wxString CallStrftime(const wxChar *format, const tm* tm)
+{
+ wxChar buf[1024];
+ if ( !wxStrftime(buf, WXSIZEOF(buf), format, tm) )
+ {
+ // is ti really possible that 1024 is too short?
+ wxFAIL_MSG(_T("strftime() failed"));
+ }
+
+ return wxString(buf);
+}
+
+// if year and/or month have invalid values, replace them with the current ones
+static void ReplaceDefaultYearMonthWithCurrent(int *year,
+ wxDateTime::Month *month)
+{
+ struct tm *tmNow = NULL;
+
+ if ( *year == wxDateTime::Inv_Year )
+ {
+ tmNow = wxDateTime::GetTmNow();
+
+ *year = 1900 + tmNow->tm_year;
+ }
+
+ if ( *month == wxDateTime::Inv_Month )
+ {
+ if ( !tmNow )
+ tmNow = wxDateTime::GetTmNow();
+
+ *month = (wxDateTime::Month)tmNow->tm_mon;
+ }
+}
+
// ============================================================================
// implementation of wxDateTime
// ============================================================================
// static data
// ----------------------------------------------------------------------------
-Country wxDateTime::ms_country;
+wxDateTime::Country wxDateTime::ms_country = wxDateTime::Country_Unknown;
wxDateTime wxDateTime::ms_InvDateTime;
+// ----------------------------------------------------------------------------
+// struct Tm
+// ----------------------------------------------------------------------------
+
+wxDateTime::Tm::Tm()
+{
+ year = (wxDateTime_t)wxDateTime::Inv_Year;
+ mon = wxDateTime::Inv_Month;
+ mday = 0;
+ hour = min = sec = msec = 0;
+ wday = wxDateTime::Inv_WeekDay;
+}
+
+wxDateTime::Tm::Tm(const struct tm& tm)
+{
+ msec = 0;
+ sec = tm.tm_sec;
+ min = tm.tm_min;
+ hour = tm.tm_hour;
+ mday = tm.tm_mday;
+ mon = (wxDateTime::Month)tm.tm_mon;
+ year = 1900 + tm.tm_year;
+ wday = tm.tm_wday;
+ yday = tm.tm_yday;
+}
+
+bool wxDateTime::Tm::IsValid() const
+{
+ // we allow for the leap seconds, although we don't use them (yet)
+ return (year != wxDateTime::Inv_Year) && (mon != wxDateTime::Inv_Month) &&
+ (mday < GetNumOfDaysInMonth(year, mon)) &&
+ (hour < 24) && (min < 60) && (sec < 62) && (msec < 1000);
+}
+
+void wxDateTime::Tm::ComputeWeekDay()
+{
+ wxFAIL_MSG(_T("TODO"));
+}
+
+void wxDateTime::Tm::AddMonths(int monDiff)
+{
+ // normalize the months field
+ while ( monDiff < -mon )
+ {
+ year--;
+
+ monDiff += MONTHS_IN_YEAR;
+ }
+
+ while ( monDiff + mon > MONTHS_IN_YEAR )
+ {
+ year++;
+ }
+
+ mon = (wxDateTime::Month)(mon + monDiff);
+
+ wxASSERT_MSG( mon >= 0 && mon < MONTHS_IN_YEAR, _T("logic error") );
+}
+
+void wxDateTime::Tm::AddDays(int dayDiff)
+{
+ // normalize the days field
+ mday += dayDiff;
+ while ( mday < 1 )
+ {
+ AddMonths(-1);
+
+ mday += GetNumOfDaysInMonth(year, mon);
+ }
+
+ while ( mday > GetNumOfDaysInMonth(year, mon) )
+ {
+ mday -= GetNumOfDaysInMonth(year, mon);
+
+ AddMonths(1);
+ }
+
+ wxASSERT_MSG( mday > 0 && mday <= GetNumOfDaysInMonth(year, mon),
+ _T("logic error") );
+}
+
+// ----------------------------------------------------------------------------
+// class TimeZone
+// ----------------------------------------------------------------------------
+
+wxDateTime::TimeZone::TimeZone(wxDateTime::TZ tz)
+{
+ switch ( tz )
+ {
+ case wxDateTime::Local:
+ // leave offset to be 0
+ break;
+
+ case wxDateTime::GMT_12:
+ case wxDateTime::GMT_11:
+ case wxDateTime::GMT_10:
+ case wxDateTime::GMT_9:
+ case wxDateTime::GMT_8:
+ case wxDateTime::GMT_7:
+ case wxDateTime::GMT_6:
+ case wxDateTime::GMT_5:
+ case wxDateTime::GMT_4:
+ case wxDateTime::GMT_3:
+ case wxDateTime::GMT_2:
+ case wxDateTime::GMT_1:
+ m_offset = -60*(wxDateTime::GMT0 - tz);
+ break;
+
+ case wxDateTime::GMT0:
+ case wxDateTime::GMT1:
+ case wxDateTime::GMT2:
+ case wxDateTime::GMT3:
+ case wxDateTime::GMT4:
+ case wxDateTime::GMT5:
+ case wxDateTime::GMT6:
+ case wxDateTime::GMT7:
+ case wxDateTime::GMT8:
+ case wxDateTime::GMT9:
+ case wxDateTime::GMT10:
+ case wxDateTime::GMT11:
+ case wxDateTime::GMT12:
+ m_offset = 60*(tz - wxDateTime::GMT0);
+ break;
+
+ case wxDateTime::A_CST:
+ // Central Standard Time in use in Australia = UTC + 9.5
+ m_offset = 9*60 + 30;
+ break;
+
+ default:
+ wxFAIL_MSG( _T("unknown time zone") );
+ }
+}
+
+// ----------------------------------------------------------------------------
+// static functions
+// ----------------------------------------------------------------------------
+
+/* static */
+bool wxDateTime::IsLeapYear(int year, wxDateTime::Calendar cal)
+{
+ if ( year == Inv_Year )
+ year = GetCurrentYear();
+
+ if ( cal == Gregorian )
+ {
+ // in Gregorian calendar leap years are those divisible by 4 except
+ // those divisible by 100 unless they're also divisible by 400
+ // (in some countries, like Russia and Greece, additional corrections
+ // exist, but they won't manifest themselves until 2700)
+ return (year % 4 == 0) && ((year % 100 != 0) || (year % 400 == 0));
+ }
+ else if ( cal == Julian )
+ {
+ // in Julian calendar the rule is simpler
+ return year % 4 == 0;
+ }
+ else
+ {
+ wxFAIL_MSG(_T("unknown calendar"));
+
+ return FALSE;
+ }
+}
+
+/* static */
+int wxDateTime::GetCentury(int year)
+{
+ return year > 0 ? year / 100 : year / 100 - 1;
+}
+
+/* static */
+void wxDateTime::SetCountry(wxDateTime::Country country)
+{
+ ms_country = country;
+}
+
+/* static */
+int wxDateTime::ConvertYearToBC(int year)
+{
+ // year 0 is BC 1
+ return year > 0 ? year : year - 1;
+}
+
+/* static */
+int wxDateTime::GetCurrentYear(wxDateTime::Calendar cal)
+{
+ switch ( cal )
+ {
+ case Gregorian:
+ return Now().GetYear();
+
+ case Julian:
+ wxFAIL_MSG(_T("TODO"));
+ break;
+
+ default:
+ wxFAIL_MSG(_T("unsupported calendar"));
+ break;
+ }
+
+ return Inv_Year;
+}
+
+/* static */
+wxDateTime::Month wxDateTime::GetCurrentMonth(wxDateTime::Calendar cal)
+{
+ switch ( cal )
+ {
+ case Gregorian:
+ return Now().GetMonth();
+ break;
+
+ case Julian:
+ wxFAIL_MSG(_T("TODO"));
+ break;
+
+ default:
+ wxFAIL_MSG(_T("unsupported calendar"));
+ break;
+ }
+
+ return Inv_Month;
+}
+
+/* static */
+wxDateTime::wxDateTime_t wxDateTime::GetNumberOfDays(int year, Calendar cal)
+{
+ if ( year == Inv_Year )
+ {
+ // take the current year if none given
+ year = GetCurrentYear();
+ }
+
+ switch ( cal )
+ {
+ case Gregorian:
+ case Julian:
+ return IsLeapYear(year) ? 366 : 365;
+ break;
+
+ default:
+ wxFAIL_MSG(_T("unsupported calendar"));
+ break;
+ }
+
+ return 0;
+}
+
+/* static */
+wxDateTime::wxDateTime_t wxDateTime::GetNumberOfDays(wxDateTime::Month month,
+ int year,
+ wxDateTime::Calendar cal)
+{
+ wxCHECK_MSG( month < MONTHS_IN_YEAR, 0, _T("invalid month") );
+
+ if ( cal == Gregorian || cal == Julian )
+ {
+ if ( year == Inv_Year )
+ {
+ // take the current year if none given
+ year = GetCurrentYear();
+ }
+
+ return GetNumOfDaysInMonth(year, month);
+ }
+ else
+ {
+ wxFAIL_MSG(_T("unsupported calendar"));
+
+ return 0;
+ }
+}
+
+/* static */
+wxString wxDateTime::GetMonthName(wxDateTime::Month month, bool abbr)
+{
+ wxCHECK_MSG( month != Inv_Month, _T(""), _T("invalid month") );
+
+ tm tm = { 0, 0, 0, 1, month, 76 }; // any year will do
+
+ return CallStrftime(abbr ? _T("%b") : _T("%B"), &tm);
+}
+
+/* static */
+wxString wxDateTime::GetWeekDayName(wxDateTime::WeekDay wday, bool abbr)
+{
+ wxCHECK_MSG( wday != Inv_WeekDay, _T(""), _T("invalid weekday") );
+
+ // take some arbitrary Sunday
+ tm tm = { 0, 0, 0, 28, Nov, 99 };
+
+ // and offset it by the number of days needed to get
+ tm.tm_mday += wday;
+
+ return CallStrftime(abbr ? _T("%a") : _T("%A"), &tm);
+}
+
// ----------------------------------------------------------------------------
// constructors and assignment operators
// ----------------------------------------------------------------------------
-wxDateTime& wxDateTime::Set(const struct tm& tm)
+wxDateTime& wxDateTime::Set(const struct tm& tm1)
{
- time_t timet = mktime(tm);
+ wxASSERT_MSG( IsValid(), _T("invalid wxDateTime") );
+
+ tm tm2(tm1);
+ time_t timet = mktime(&tm2);
if ( timet == (time_t)(-1) )
{
wxFAIL_MSG(_T("Invalid time"));
wxDateTime_t second,
wxDateTime_t millisec)
{
+ wxASSERT_MSG( IsValid(), _T("invalid wxDateTime") );
+
// we allow seconds to be 61 to account for the leap seconds, even if we
// don't use them really
wxCHECK_MSG( hour < 24 && second < 62 && minute < 60 && millisec < 1000,
tm->tm_min = minute;
tm->tm_sec = second;
- (void)Set(tm);
+ (void)Set(*tm);
// and finally adjust milliseconds
return SetMillisecond(millisec);
wxDateTime_t second,
wxDateTime_t millisec)
{
+ wxASSERT_MSG( IsValid(), _T("invalid wxDateTime") );
+
wxCHECK_MSG( hour < 24 && second < 62 && minute < 60 && millisec < 1000,
ms_InvDateTime,
_T("Invalid time in wxDateTime::Set()") );
- if ( year == Inv_Year )
- year = GetCurrentYear();
- if ( month == Inv_Month )
- month = GetCurrentMonth();
+ ReplaceDefaultYearMonthWithCurrent(&year, &month);
- wxCHECK_MSG( day < GetNumberOfDays(month, year), ms_InvDateTime,
+ wxCHECK_MSG( day <= GetNumberOfDays(month, year), ms_InvDateTime,
_T("Invalid date in wxDateTime::Set()") );
// the range of time_t type (inclusive)
// test only the year instead of testing for the exact end of the Unix
// time_t range - it doesn't bring anything to do more precise checks
- if ( year >= yearMaxInRange && year <= yearMaxInRange )
+ if ( year >= yearMinInRange && year <= yearMaxInRange )
{
// use the standard library version if the date is in range - this is
- // probably much more efficient than our code
+ // probably more efficient than our code
struct tm tm;
- tm.tm_year = year;
+ tm.tm_year = year - 1900;
tm.tm_mon = month;
tm.tm_mday = day;
tm.tm_hour = hour;
else
{
// do time calculations ourselves: we want to calculate the number of
- // milliseconds between the given date and the epoch (necessarily
- // negative)
+ // milliseconds between the given date and the epoch
+
+ // get the JDN for the midnight of this day
+ m_time = GetTruncatedJDN(day, month, year);
+ m_time -= EPOCH_JDN;
+ m_time *= SECONDS_PER_DAY * TIME_T_FACTOR;
+
+ Add(wxTimeSpan(hour, minute, second, millisec));
}
return *this;
}
+
+wxDateTime& wxDateTime::Set(double jdn)
+{
+ m_time = (jdn - 0.5 - EPOCH_JDN) * TIME_T_FACTOR;
+
+ return *this;
+}
+
+// ----------------------------------------------------------------------------
+// time_t <-> broken down time conversions
+// ----------------------------------------------------------------------------
+
+wxDateTime::Tm wxDateTime::GetTm() const
+{
+ wxASSERT_MSG( IsValid(), _T("invalid wxDateTime") );
+
+ time_t time = GetTicks();
+ if ( time != (time_t)-1 )
+ {
+ // use C RTL functions
+ tm *tm = localtime(&time);
+
+ // should never happen
+ wxCHECK_MSG( tm, Tm(), _T("localtime() failed") );
+
+ return Tm(*tm);
+ }
+ else
+ {
+ // CREDIT: the algorithm was taken from Peter Baum's home page
+
+ // calculate the Gregorian date from JDN for the midnight of our date
+ wxLongLong timeMidnight = m_time;
+ long timeOnly = (m_time % MILLISECONDS_PER_DAY).GetLo();
+ timeMidnight -= timeOnly;
+
+ // TODO this probably could be optimised somehow...
+
+ double jdn = (timeMidnight / MILLISECONDS_PER_DAY).GetLo();
+ jdn += EPOCH_JDN + 0.5;
+ long z = jdn - 1721118.5;
+ double r = jdn - 1721118.5 - z;
+ double g = z - 0.25;
+ long a = g/36524.25; // number of days per year
+ long b = a - a / 4;
+ int year = (b + g) / 365.25;
+ long c = b + z - 365.25*year;
+ int month = (5*c + 456)/153;
+ int day = c - (153*month - 457)/5 + (r < 0.5 ? 0 : 1);
+ if ( month > 12 )
+ {
+ year++;
+ month -= 12;
+ }
+
+ Tm tm;
+ tm.year = year;
+ tm.mon = (Month)(month - 1); // algorithm yields 1 for January, not 0
+ tm.mday = day;
+ tm.msec = timeOnly % 1000;
+ timeOnly -= tm.msec;
+ timeOnly /= 1000; // now we have time in seconds
+
+ tm.sec = timeOnly % 60;
+ timeOnly -= tm.sec;
+ timeOnly /= 60; // now we have time in minutes
+
+ tm.min = timeOnly % 60;
+ timeOnly -= tm.min;
+
+ tm.hour = timeOnly / 60;
+
+ return tm;
+ }
+}
+
+wxDateTime& wxDateTime::SetYear(int year)
+{
+ wxASSERT_MSG( IsValid(), _T("invalid wxDateTime") );
+
+ Tm tm(GetTm());
+ tm.year = year;
+ Set(tm);
+
+ return *this;
+}
+
+wxDateTime& wxDateTime::SetMonth(Month month)
+{
+ wxASSERT_MSG( IsValid(), _T("invalid wxDateTime") );
+
+ Tm tm(GetTm());
+ tm.mon = month;
+ Set(tm);
+
+ return *this;
+}
+
+wxDateTime& wxDateTime::SetDay(wxDateTime_t mday)
+{
+ wxASSERT_MSG( IsValid(), _T("invalid wxDateTime") );
+
+ Tm tm(GetTm());
+ tm.mday = mday;
+ Set(tm);
+
+ return *this;
+}
+
+wxDateTime& wxDateTime::SetHour(wxDateTime_t hour)
+{
+ wxASSERT_MSG( IsValid(), _T("invalid wxDateTime") );
+
+ Tm tm(GetTm());
+ tm.hour = hour;
+ Set(tm);
+
+ return *this;
+}
+
+wxDateTime& wxDateTime::SetMinute(wxDateTime_t min)
+{
+ wxASSERT_MSG( IsValid(), _T("invalid wxDateTime") );
+
+ Tm tm(GetTm());
+ tm.min = min;
+ Set(tm);
+
+ return *this;
+}
+
+wxDateTime& wxDateTime::SetSecond(wxDateTime_t sec)
+{
+ wxASSERT_MSG( IsValid(), _T("invalid wxDateTime") );
+
+ Tm tm(GetTm());
+ tm.sec = sec;
+ Set(tm);
+
+ return *this;
+}
+
+wxDateTime& wxDateTime::SetMillisecond(wxDateTime_t millisecond)
+{
+ wxASSERT_MSG( IsValid(), _T("invalid wxDateTime") );
+
+ // we don't need to use GetTm() for this one
+ m_time -= m_time % 1000l;
+ m_time += millisecond;
+
+ return *this;
+}
+
+// ----------------------------------------------------------------------------
+// wxDateTime arithmetics
+// ----------------------------------------------------------------------------
+
+wxDateTime& wxDateTime::Add(const wxDateSpan& diff)
+{
+ Tm tm(GetTm());
+
+ tm.year += diff.GetYears();
+ tm.AddMonths(diff.GetMonths());
+ tm.AddDays(diff.GetTotalDays());
+
+ Set(tm);
+
+ return *this;
+}
+
+// ----------------------------------------------------------------------------
+// Weekday and monthday stuff
+// ----------------------------------------------------------------------------
+
+wxDateTime& wxDateTime::SetToLastMonthDay(Month month,
+ int year)
+{
+ // take the current month/year if none specified
+ ReplaceDefaultYearMonthWithCurrent(&year, &month);
+
+ return Set(GetNumOfDaysInMonth(year, month), month, year);
+}
+
+bool wxDateTime::SetToWeekDay(WeekDay weekday,
+ int n,
+ Month month,
+ int year)
+{
+ wxCHECK_MSG( weekday != Inv_WeekDay, FALSE, _T("invalid weekday") );
+
+ // we don't check explicitly that -5 <= n <= 5 because we will return FALSE
+ // anyhow in such case - but may be should still give an assert for it?
+
+ // take the current month/year if none specified
+ ReplaceDefaultYearMonthWithCurrent(&year, &month);
+
+ wxDateTime dt;
+
+ // TODO this probably could be optimised somehow...
+
+ if ( n > 0 )
+ {
+ // get the first day of the month
+ dt.Set(1, month, year);
+
+ // get its wday
+ WeekDay wdayFirst = dt.GetWeekDay();
+
+ // go to the first weekday of the month
+ int diff = weekday - wdayFirst;
+ if ( diff < 0 )
+ diff += 7;
+
+ // add advance n-1 weeks more
+ diff += 7*(n - 1);
+
+ dt -= wxDateSpan::Days(diff);
+ }
+ else
+ {
+ // get the last day of the month
+ dt.SetToLastMonthDay(month, year);
+
+ // get its wday
+ WeekDay wdayLast = dt.GetWeekDay();
+
+ // go to the last weekday of the month
+ int diff = wdayLast - weekday;
+ if ( diff < 0 )
+ diff += 7;
+
+ // and rewind n-1 weeks from there
+ diff += 7*(n - 1);
+
+ dt -= wxDateSpan::Days(diff);
+ }
+
+ // check that it is still in the same month
+ if ( dt.GetMonth() == month )
+ {
+ *this = dt;
+
+ return TRUE;
+ }
+ else
+ {
+ // no such day in this month
+ return FALSE;
+ }
+}
+
+// ----------------------------------------------------------------------------
+// Julian day number conversion and related stuff
+// ----------------------------------------------------------------------------
+
+double wxDateTime::GetJulianDayNumber() const
+{
+ Tm tm(GetTm());
+
+ double result = GetTruncatedJDN(tm.mday, tm.mon, tm.year);
+
+ // add the part GetTruncatedJDN() neglected
+ result += 0.5;
+
+ // and now add the time: 86400 sec = 1 JDN
+ return result + ((double)(60*(60*tm.hour + tm.min) + tm.sec)) / 86400;
+}
+
+double wxDateTime::GetRataDie() const
+{
+ // March 1 of the year 0 is Rata Die day -306 and JDN 1721119.5
+ return GetJulianDayNumber() - 1721119.5 - 306;
+}
+
+// ----------------------------------------------------------------------------
+// timezone stuff
+// ----------------------------------------------------------------------------
+
+wxDateTime& wxDateTime::MakeUTC()
+{
+ return Add(wxTimeSpan::Seconds(GetTimeZone()));
+}
+
+wxDateTime& wxDateTime::MakeTimezone(const TimeZone& tz)
+{
+ int minDiff = GetTimeZone() / SECONDS_IN_MINUTE + tz.GetOffset();
+ return Add(wxTimeSpan::Minutes(minDiff));
+}
+
+wxDateTime& wxDateTime::MakeLocalTime(const TimeZone& tz)
+{
+ int minDiff = GetTimeZone() / SECONDS_IN_MINUTE + tz.GetOffset();
+ return Substract(wxTimeSpan::Minutes(minDiff));
+}
+
+// ----------------------------------------------------------------------------
+// wxDateTime to/from text representations
+// ----------------------------------------------------------------------------
+
+wxString wxDateTime::Format(const wxChar *format) const
+{
+ wxCHECK_MSG( format, _T(""), _T("NULL format in wxDateTime::Format") );
+
+ time_t time = GetTicks();
+ if ( time != (time_t)-1 )
+ {
+ // use strftime()
+ tm *tm = localtime(&time);
+
+ // should never happen
+ wxCHECK_MSG( tm, _T(""), _T("localtime() failed") );
+
+ return CallStrftime(format, tm);
+ }
+ else
+ {
+ // use a hack and still use strftime(): make a copy of the format and
+ // replace all occurences of YEAR in it with some unique string not
+ // appearing anywhere else in it, then use strftime() to format the
+ // date in year YEAR and then replace YEAR back by the real year and
+ // the unique replacement string back with YEAR where YEAR is any year
+ // in the range supported by strftime() (1970 - 2037) which is equal to
+ // the real year modulo 28 (so the week days coincide for them)
+
+ // find the YEAR
+ int yearReal = GetYear();
+ int year = 1970 + yearReal % 28;
+
+ wxString strYear;
+ strYear.Printf(_T("%d"), year);
+
+ // find a string not occuring in format (this is surely not optimal way
+ // of doing it... improvements welcome!)
+ wxString fmt = format;
+ wxString replacement = (wxChar)-1;
+ while ( fmt.Find(replacement) != wxNOT_FOUND )
+ {
+ replacement << (wxChar)-1;
+ }
+
+ // replace all occurences of year with it
+ bool wasReplaced = fmt.Replace(strYear, replacement) > 0;
+
+ // use strftime() to format the same date but in supported year
+ wxDateTime dt(*this);
+ dt.SetYear(year);
+ wxString str = dt.Format(format);
+
+ // now replace the occurence of 1999 with the real year
+ wxString strYearReal;
+ strYearReal.Printf(_T("%d"), yearReal);
+ str.Replace(strYear, strYearReal);
+
+ // and replace back all occurences of replacement string
+ if ( wasReplaced )
+ str.Replace(replacement, strYear);
+
+ return str;
+ }
+}
+
+// ============================================================================
+// wxTimeSpan
+// ============================================================================
+
+// not all strftime(3) format specifiers make sense here because, for example,
+// a time span doesn't have a year nor a timezone
+//
+// Here are the ones which are supported (all of them are supported by strftime
+// as well):
+// %H hour in 24 hour format
+// %M minute (00 - 59)
+// %S second (00 - 59)
+// %% percent sign
+//
+// Also, for MFC CTimeSpan compatibility, we support
+// %D number of days
+//
+// And, to be better than MFC :-), we also have
+// %E number of wEeks
+// %l milliseconds (000 - 999)
+wxString wxTimeSpan::Format(const wxChar *format) const
+{
+ wxCHECK_MSG( format, _T(""), _T("NULL format in wxTimeSpan::Format") );
+
+ wxString str;
+ str.Alloc(strlen(format));
+
+ for ( const wxChar *pch = format; pch; pch++ )
+ {
+ wxChar ch = *pch;
+
+ if ( ch == '%' )
+ {
+ wxString tmp;
+
+ ch = *pch++;
+ switch ( ch )
+ {
+ default:
+ wxFAIL_MSG( _T("invalid format character") );
+ // fall through
+
+ case '%':
+ // will get to str << ch below
+ break;
+
+ case 'D':
+ tmp.Printf(_T("%d"), GetDays());
+ break;
+
+ case 'E':
+ tmp.Printf(_T("%d"), GetWeeks());
+ break;
+
+ case 'H':
+ tmp.Printf(_T("%02d"), GetHours());
+ break;
+
+ case 'l':
+ tmp.Printf(_T("%03d"), GetMilliseconds());
+ break;
+
+ case 'M':
+ tmp.Printf(_T("%02d"), GetMinutes());
+ break;
+
+ case 'S':
+ tmp.Printf(_T("%02d"), GetSeconds());
+ break;
+ }
+
+ if ( !!tmp )
+ {
+ str += tmp;
+
+ // skip str += ch below
+ continue;
+ }
+ }
+
+ str += ch;
+ }
+
+ return str;
+}