- // use strftime()
- tm *tm;
- if ( tz.GetOffset() == -GetTimeZone() )
- {
- // we are working with local time
- tm = localtime(&time);
-
- // should never happen
- wxCHECK_MSG( tm, wxEmptyString, _T("localtime() failed") );
- }
- else
- {
- time += tz.GetOffset();
-
- if ( time >= 0 )
- {
- tm = gmtime(&time);
-
- // should never happen
- wxCHECK_MSG( tm, wxEmptyString, _T("gmtime() failed") );
- }
- else
- {
- tm = (struct tm *)NULL;
- }
- }
-
- if ( tm )
- {
- return CallStrftime(format, tm);
- }
- //else: use generic code below
- }
-
- // we only parse ANSI C format specifications here, no POSIX 2
- // complications, no GNU extensions
- Tm tm = GetTm(tz);
-
- // used for calls to strftime() when we only deal with time
- struct tm tmTimeOnly;
- tmTimeOnly.tm_hour = tm.hour;
- tmTimeOnly.tm_min = tm.min;
- tmTimeOnly.tm_sec = tm.sec;
- tmTimeOnly.tm_wday = 0;
- tmTimeOnly.tm_yday = 0;
- tmTimeOnly.tm_mday = 1; // any date will do
- tmTimeOnly.tm_mon = 0;
- tmTimeOnly.tm_year = 76;
- tmTimeOnly.tm_isdst = 0; // no DST, we adjust for tz ourselves
-
- wxString tmp, res;
- for ( const wxChar *p = format; *p; p++ )
- {
- if ( *p != _T('%') )
- {
- // copy as is
- res += *p;
-
- continue;
- }
-
- // start of the format specification
- switch ( *++p )
- {
- case _T('a'): // a weekday name
- case _T('A'):
- // second parameter should be TRUE for abbreviated names
- res += GetWeekDayName(tm.GetWeekDay(), *p == _T('a'));
- break;
-
- case _T('b'): // a month name
- case _T('B'):
- // second parameter should be TRUE for abbreviated names
- res += GetMonthName(tm.mon, *p == _T('b'));
- break;
-
- case _T('c'): // locale default date and time representation
- case _T('x'): // locale default date representation
- //
- // the problem: there is no way to know what do these format
- // specifications correspond to for the current locale.
- //
- // the solution: use a hack and still use strftime(): first
- // find the YEAR which is a year in the strftime() range (1970
- // - 2038) whose Jan 1 falls on the same week day as the Jan 1
- // of the real year. Then 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. Notice that "all occurences of YEAR"
- // means all occurences of 4 digit as well as 2 digit form!
- //
- // the bugs: we assume that neither of %c nor %x contains any
- // fields which may change between the YEAR and real year. For
- // example, the week number (%U, %W) and the day number (%j)
- // will change if one of these years is leap and the other one
- // is not!
- {
- // find the YEAR: normally, for any year X, Jan 1 or the
- // year X + 28 is the same weekday as Jan 1 of X (because
- // the weekday advances by 1 for each normal X and by 2
- // for each leap X, hence by 5 every 4 years or by 35
- // which is 0 mod 7 every 28 years) but this rule breaks
- // down if there are years between X and Y which are
- // divisible by 4 but not leap (i.e. divisible by 100 but
- // not 400), hence the correction.
-
- int yearReal = GetYear(tz);
- int mod28 = yearReal % 28;
-
- // be careful to not go too far - we risk to leave the
- // supported range
- int year;
- if ( mod28 < 10 )
- {
- year = 1988 + mod28; // 1988 == 0 (mod 28)
- }
- else
- {
- year = 1970 + mod28 - 10; // 1970 == 10 (mod 28)
- }
-
- int nCentury = year / 100,
- nCenturyReal = yearReal / 100;
-
- // need to adjust for the years divisble by 400 which are
- // not leap but are counted like leap ones if we just take
- // the number of centuries in between for nLostWeekDays
- int nLostWeekDays = (nCentury - nCenturyReal) -
- (nCentury / 4 - nCenturyReal / 4);
-
- // we have to gain back the "lost" weekdays: note that the
- // effect of this loop is to not do anything to
- // nLostWeekDays (which we won't use any more), but to
- // (indirectly) set the year correctly
- while ( (nLostWeekDays % 7) != 0 )
- {
- nLostWeekDays += year++ % 4 ? 1 : 2;
- }
-
- // at any rate, we couldn't go further than 1988 + 9 + 28!
- wxASSERT_MSG( year < 2030,
- _T("logic error in wxDateTime::Format") );
-
- wxString strYear, strYear2;
- strYear.Printf(_T("%d"), year);
- strYear2.Printf(_T("%d"), year % 100);
-
- // find two strings 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;
- }
-
- wxString replacement2 = (wxChar)-2;
- while ( fmt.Find(replacement) != wxNOT_FOUND )
- {
- replacement << (wxChar)-2;
- }
-
- // replace all occurences of year with it
- bool wasReplaced = fmt.Replace(strYear, replacement) > 0;
- if ( !wasReplaced )
- wasReplaced = fmt.Replace(strYear2, replacement2) > 0;
-
- // use strftime() to format the same date but in supported
- // year
- //
- // NB: we assume that strftime() doesn't check for the
- // date validity and will happily format the date
- // corresponding to Feb 29 of a non leap year (which
- // may happen if yearReal was leap and year is not)
- struct tm tmAdjusted;
- tmAdjusted.tm_hour = tm.hour;
- tmAdjusted.tm_min = tm.min;
- tmAdjusted.tm_sec = tm.sec;
- tmAdjusted.tm_wday = tm.GetWeekDay();
- tmAdjusted.tm_yday = GetDayOfYear();
- tmAdjusted.tm_mday = tm.mday;
- tmAdjusted.tm_mon = tm.mon;
- tmAdjusted.tm_year = year - 1900;
- tmAdjusted.tm_isdst = 0; // no DST, already adjusted
- wxString str = CallStrftime(*p == _T('c') ? _T("%c")
- : _T("%x"),
- &tmAdjusted);
-
- // now replace the occurence of 1999 with the real year
- wxString strYearReal, strYearReal2;
- strYearReal.Printf(_T("%04d"), yearReal);
- strYearReal2.Printf(_T("%02d"), yearReal % 100);
- str.Replace(strYear, strYearReal);
- str.Replace(strYear2, strYearReal2);
-
- // and replace back all occurences of replacement string
- if ( wasReplaced )
- {
- str.Replace(replacement2, strYear2);
- str.Replace(replacement, strYear);
- }
-
- res += str;
- }
- break;
-
- case _T('d'): // day of a month (01-31)
- tmp.Printf(_T("%02d"), tm.mday);
- res += tmp;
- break;
-
- case _T('H'): // hour in 24h format (00-23)
- tmp.Printf(_T("%02d"), tm.hour);
- res += tmp;
- break;
-
- case _T('I'): // hour in 12h format (01-12)
- {
- // 24h -> 12h, 0h -> 12h too
- int hour12 = tm.hour > 12 ? tm.hour - 12
- : tm.hour ? tm.hour : 12;
- tmp.Printf(_T("%02d"), hour12);
- res += tmp;
- }
- break;
-
- case _T('j'): // day of the year
- tmp.Printf(_T("%03d"), GetDayOfYear(tz));
- res += tmp;
- break;
-
- case _T('m'): // month as a number (01-12)
- tmp.Printf(_T("%02d"), tm.mon + 1);
- res += tmp;
- break;
-
- case _T('M'): // minute as a decimal number (00-59)
- tmp.Printf(_T("%02d"), tm.min);
- res += tmp;
- break;
-
- case _T('p'): // AM or PM string
- res += CallStrftime(_T("%p"), &tmTimeOnly);
- break;
-
- case _T('S'): // second as a decimal number (00-61)
- tmp.Printf(_T("%02d"), tm.sec);
- res += tmp;
- break;
-
- case _T('U'): // week number in the year (Sunday 1st week day)
- tmp.Printf(_T("%02d"),
- (GetDayOfYear(tz) - tm.GetWeekDay() + 7) / 7);
- res += tmp;
- break;
-
- case _T('W'): // week number in the year (Monday 1st week day)
- tmp.Printf(_T("%02d"), GetWeekOfYear(tz));
- res += tmp;
- break;
-
- case _T('w'): // weekday as a number (0-6), Sunday = 0
- tmp.Printf(_T("%d"), tm.GetWeekDay());
- res += tmp;
- break;
-
- // case _T('x'): -- handled with "%c"
-
- case _T('X'): // locale default time representation
- // just use strftime() to format the time for us
- res += CallStrftime(_T("%X"), &tmTimeOnly);
- break;
-
- case _T('y'): // year without century (00-99)
- tmp.Printf(_T("%02d"), tm.year % 100);
- res += tmp;
- break;
-
- case _T('Y'): // year with century
- tmp.Printf(_T("%04d"), tm.year);
- res += tmp;
- break;
-
- case _T('Z'): // timezone name
- res += CallStrftime(_T("%Z"), &tmTimeOnly);
- break;
-
- default:
- wxFAIL_MSG(_T("unknown format specificator"));
-
- // fall through and just copy it nevertheless
-
- case _T('%'): // a percent sign
- res += *p;
- break;
-
- case 0:
- wxFAIL_MSG(_T("missing format at the end of string"));
-
- // just put the '%' which was the last char in format
- res += _T('%');
- break;
- }
projects / wxWidgets.git / blobdiff