]> git.saurik.com Git - wxWidgets.git/blobdiff - src/common/datetime.cpp
Bug fix.
[wxWidgets.git] / src / common / datetime.cpp
index 282fde1baeb6b3ef85c2df0674ec41b19747ea5c..4e68a76cd23edd1388e046523804da8c2893fba3 100644 (file)
 #if !defined(wxUSE_DATETIME) || wxUSE_DATETIME
 
 #ifndef WX_PRECOMP
 #if !defined(wxUSE_DATETIME) || wxUSE_DATETIME
 
 #ifndef WX_PRECOMP
+    #ifdef __WXMSW__
+        #include "wx/msw/wrapwin.h"
+    #endif
     #include "wx/string.h"
     #include "wx/log.h"
     #include "wx/string.h"
     #include "wx/log.h"
+    #include "wx/intl.h"
+    #include "wx/stopwatch.h"           // for wxGetLocalTimeMillis()
+    #include "wx/module.h"
 #endif // WX_PRECOMP
 
 #endif // WX_PRECOMP
 
-#include "wx/intl.h"
 #include "wx/thread.h"
 #include "wx/tokenzr.h"
 #include "wx/thread.h"
 #include "wx/tokenzr.h"
-#include "wx/module.h"
 
 #include <ctype.h>
 
 #ifdef __WINDOWS__
 
 #include <ctype.h>
 
 #ifdef __WINDOWS__
-    #include "wx/msw/wrapwin.h"
     #include <winnls.h>
     #ifndef __WXWINCE__
         #include <locale.h>
     #include <winnls.h>
     #ifndef __WXWINCE__
         #include <locale.h>
@@ -86,7 +89,6 @@
 #endif
 
 #include "wx/datetime.h"
 #endif
 
 #include "wx/datetime.h"
-#include "wx/stopwatch.h"           // for wxGetLocalTimeMillis()
 
 const long wxDateTime::TIME_T_FACTOR = 1000l;
 
 
 const long wxDateTime::TIME_T_FACTOR = 1000l;
 
@@ -169,18 +171,43 @@ wxCUSTOM_TYPE_INFO(wxDateTime, wxToStringConverter<wxDateTime> , wxFromStringCon
     #endif
 #endif // !WX_TIMEZONE && !WX_GMTOFF_IN_TM
 
     #endif
 #endif // !WX_TIMEZONE && !WX_GMTOFF_IN_TM
 
+#if (!defined(HAVE_LOCALTIME_R) || !defined(HAVE_GMTIME_R)) && wxUSE_THREADS && !defined(__WINDOWS__)
+static wxMutex timeLock;
+#endif
+
+#ifndef HAVE_LOCALTIME_R
+struct tm *wxLocaltime_r(const time_t* ticks, struct tm* temp)
+{
+#if wxUSE_THREADS && !defined(__WINDOWS__)
+  // No need to waste time with a mutex on windows since it's using
+  // thread local storage for localtime anyway.
+  wxMutexLocker locker(timeLock);
+#endif
+  memcpy(temp, localtime(ticks), sizeof(struct tm));
+  return temp;
+}
+#endif
+
+#ifndef HAVE_GMTIME_R
+struct tm *wxGmtime_r(const time_t* ticks, struct tm* temp)
+{
+#if wxUSE_THREADS && !defined(__WINDOWS__)
+  // No need to waste time with a mutex on windows since it's
+  // using thread local storage for gmtime anyway.
+  wxMutexLocker locker(timeLock);
+#endif
+  memcpy(temp, gmtime(ticks), sizeof(struct tm));
+  return temp;
+}
+#endif
+
 // ----------------------------------------------------------------------------
 // macros
 // ----------------------------------------------------------------------------
 
 // debugging helper: just a convenient replacement of wxCHECK()
 // ----------------------------------------------------------------------------
 // macros
 // ----------------------------------------------------------------------------
 
 // debugging helper: just a convenient replacement of wxCHECK()
-#define wxDATETIME_CHECK(expr, msg)     \
-        if ( !(expr) )                  \
-        {                               \
-            wxFAIL_MSG(msg);            \
-            *this = wxInvalidDateTime;  \
-            return *this;               \
-        }
+#define wxDATETIME_CHECK(expr, msg) \
+    wxCHECK2_MSG(expr, *this = wxInvalidDateTime; return *this, msg)
 
 // ----------------------------------------------------------------------------
 // private classes
 
 // ----------------------------------------------------------------------------
 // private classes
@@ -302,32 +329,32 @@ wxDateTime::wxDateTime_t GetNumOfDaysInMonth(int year, wxDateTime::Month month)
 // (in seconds)
 static int GetTimeZone()
 {
 // (in seconds)
 static int GetTimeZone()
 {
-#ifdef WX_GMTOFF_IN_TM
     // set to true when the timezone is set
     static bool s_timezoneSet = false;
     static long gmtoffset = LONG_MAX; // invalid timezone
 
     // set to true when the timezone is set
     static bool s_timezoneSet = false;
     static long gmtoffset = LONG_MAX; // invalid timezone
 
-    // ensure that the timezone variable is set by calling localtime
+    // ensure that the timezone variable is set by calling wxLocaltime_r
     if ( !s_timezoneSet )
     {
     if ( !s_timezoneSet )
     {
-        // just call localtime() instead of figuring out whether this system
-        // supports tzset(), _tzset() or something else
+        // just call wxLocaltime_r() instead of figuring out whether this
+        // system supports tzset(), _tzset() or something else
         time_t t = 0;
         time_t t = 0;
-        struct tm *tm;
+        struct tm tm;
 
 
-        tm = localtime(&t);
+        wxLocaltime_r(&t, &tm);
         s_timezoneSet = true;
 
         s_timezoneSet = true;
 
+#ifdef WX_GMTOFF_IN_TM
         // note that GMT offset is the opposite of time zone and so to return
         // consistent results in both WX_GMTOFF_IN_TM and !WX_GMTOFF_IN_TM
         // cases we have to negate it
         // note that GMT offset is the opposite of time zone and so to return
         // consistent results in both WX_GMTOFF_IN_TM and !WX_GMTOFF_IN_TM
         // cases we have to negate it
-        gmtoffset = -tm->tm_gmtoff;
+        gmtoffset = -tm.tm_gmtoff;
+#else // !WX_GMTOFF_IN_TM
+        gmtoffset = WX_TIMEZONE;
+#endif // WX_GMTOFF_IN_TM/!WX_GMTOFF_IN_TM
     }
 
     return (int)gmtoffset;
     }
 
     return (int)gmtoffset;
-#else // !WX_GMTOFF_IN_TM
-    return (int)WX_TIMEZONE;
-#endif // WX_GMTOFF_IN_TM/!WX_GMTOFF_IN_TM
 }
 
 // return the integral part of the JDN for the midnight of the given date (to
 }
 
 // return the integral part of the JDN for the midnight of the given date (to
@@ -430,10 +457,11 @@ static void ReplaceDefaultYearMonthWithCurrent(int *year,
                                                wxDateTime::Month *month)
 {
     struct tm *tmNow = NULL;
                                                wxDateTime::Month *month)
 {
     struct tm *tmNow = NULL;
+    struct tm tmstruct;
 
     if ( *year == wxDateTime::Inv_Year )
     {
 
     if ( *year == wxDateTime::Inv_Year )
     {
-        tmNow = wxDateTime::GetTmNow();
+        tmNow = wxDateTime::GetTmNow(&tmstruct);
 
         *year = 1900 + tmNow->tm_year;
     }
 
         *year = 1900 + tmNow->tm_year;
     }
@@ -441,7 +469,7 @@ static void ReplaceDefaultYearMonthWithCurrent(int *year,
     if ( *month == wxDateTime::Inv_Month )
     {
         if ( !tmNow )
     if ( *month == wxDateTime::Inv_Month )
     {
         if ( !tmNow )
-            tmNow = wxDateTime::GetTmNow();
+            tmNow = wxDateTime::GetTmNow(&tmstruct);
 
         *month = (wxDateTime::Month)tmNow->tm_mon;
     }
 
         *month = (wxDateTime::Month)tmNow->tm_mon;
     }
@@ -522,6 +550,13 @@ static wxDateTime::WeekDay GetWeekDayFromName(const wxString& name, int flags)
     return wd;
 }
 
     return wd;
 }
 
+/* static */
+struct tm *wxDateTime::GetTmNow(struct tm *tmstruct)
+{
+    time_t t = GetTimeNow();
+    return wxLocaltime_r(&t, tmstruct);
+}
+
 // scans all digits (but no more than len) and returns the resulting number
 static bool GetNumericToken(size_t len, const wxChar*& p, unsigned long *number)
 {
 // scans all digits (but no more than len) and returns the resulting number
 static bool GetNumericToken(size_t len, const wxChar*& p, unsigned long *number)
 {
@@ -988,7 +1023,8 @@ wxDateTime::Country wxDateTime::GetCountry()
     {
         // try to guess from the time zone name
         time_t t = time(NULL);
     {
         // try to guess from the time zone name
         time_t t = time(NULL);
-        struct tm *tm = localtime(&t);
+        struct tm tmstruct;
+        struct tm *tm = wxLocaltime_r(&t, &tmstruct);
 
         wxString tz = CallStrftime(_T("%Z"), tm);
         if ( tz == _T("WET") || tz == _T("WEST") )
 
         wxString tz = CallStrftime(_T("%Z"), tm);
         if ( tz == _T("WET") || tz == _T("WEST") )
@@ -1311,9 +1347,10 @@ wxDateTime& wxDateTime::Set(wxDateTime_t hour,
                       _T("Invalid time in wxDateTime::Set()") );
 
     // get the current date from system
                       _T("Invalid time in wxDateTime::Set()") );
 
     // get the current date from system
-    struct tm *tm = GetTmNow();
+    struct tm tmstruct;
+    struct tm *tm = GetTmNow(&tmstruct);
 
 
-    wxDATETIME_CHECK( tm, _T("localtime() failed") );
+    wxDATETIME_CHECK( tm, _T("wxLocaltime_r() failed") );
 
     // make a copy so it isn't clobbered by the call to mktime() below
     struct tm tm1(*tm);
 
     // make a copy so it isn't clobbered by the call to mktime() below
     struct tm tm1(*tm);
@@ -1479,7 +1516,8 @@ unsigned long wxDateTime::GetAsDOS() const
 {
     unsigned long ddt;
     time_t ticks = GetTicks();
 {
     unsigned long ddt;
     time_t ticks = GetTicks();
-    struct tm *tm = localtime(&ticks);
+    struct tm tmstruct;
+    struct tm *tm = wxLocaltime_r(&ticks, &tmstruct);
 
     long year = tm->tm_year;
     year -= 80;
 
     long year = tm->tm_year;
     year -= 80;
@@ -1517,14 +1555,15 @@ wxDateTime::Tm wxDateTime::GetTm(const TimeZone& tz) const
     if ( time != (time_t)-1 )
     {
         // use C RTL functions
     if ( time != (time_t)-1 )
     {
         // use C RTL functions
+        struct tm tmstruct;
         tm *tm;
         if ( tz.GetOffset() == -GetTimeZone() )
         {
             // we are working with local time
         tm *tm;
         if ( tz.GetOffset() == -GetTimeZone() )
         {
             // we are working with local time
-            tm = localtime(&time);
+            tm = wxLocaltime_r(&time, &tmstruct);
 
             // should never happen
 
             // should never happen
-            wxCHECK_MSG( tm, Tm(), _T("localtime() failed") );
+            wxCHECK_MSG( tm, Tm(), _T("wxLocaltime_r() failed") );
         }
         else
         {
         }
         else
         {
@@ -1536,10 +1575,10 @@ wxDateTime::Tm wxDateTime::GetTm(const TimeZone& tz) const
             if ( time >= 0 )
 #endif
             {
             if ( time >= 0 )
 #endif
             {
-                tm = gmtime(&time);
+                tm = wxGmtime_r(&time, &tmstruct);
 
                 // should never happen
 
                 // should never happen
-                wxCHECK_MSG( tm, Tm(), _T("gmtime() failed") );
+                wxCHECK_MSG( tm, Tm(), _T("wxGmtime_r() failed") );
             }
             else
             {
             }
             else
             {
@@ -1773,6 +1812,7 @@ wxDateTime::SetToWeekOfYear(int year, wxDateTime_t numWeek, WeekDay wd)
     return dt;
 }
 
     return dt;
 }
 
+#if WXWIN_COMPATIBILITY_2_6
 // use a separate function to avoid warnings about using deprecated
 // SetToTheWeek in GetWeek below
 static wxDateTime
 // use a separate function to avoid warnings about using deprecated
 // SetToTheWeek in GetWeek below
 static wxDateTime
@@ -1810,6 +1850,7 @@ wxDateTime wxDateTime::GetWeek(wxDateTime_t numWeek,
 {
     return ::SetToTheWeek(GetYear(), numWeek, weekday, flags);
 }
 {
     return ::SetToTheWeek(GetYear(), numWeek, weekday, flags);
 }
+#endif // WXWIN_COMPATIBILITY_2_6
 
 wxDateTime& wxDateTime::SetToLastMonthDay(Month month,
                                           int year)
 
 wxDateTime& wxDateTime::SetToLastMonthDay(Month month,
                                           int year)
@@ -2120,9 +2161,10 @@ int wxDateTime::IsDST(wxDateTime::Country country) const
     time_t timet = GetTicks();
     if ( timet != (time_t)-1 )
     {
     time_t timet = GetTicks();
     if ( timet != (time_t)-1 )
     {
-        tm *tm = localtime(&timet);
+        struct tm tmstruct;
+        tm *tm = wxLocaltime_r(&timet, &tmstruct);
 
 
-        wxCHECK_MSG( tm, -1, _T("localtime() failed") );
+        wxCHECK_MSG( tm, -1, _T("wxLocaltime_r() failed") );
 
         return tm->tm_isdst;
     }
 
         return tm->tm_isdst;
     }
@@ -2184,14 +2226,15 @@ wxString wxDateTime::Format(const wxChar *format, const TimeZone& tz) const
     if ( (time != (time_t)-1) && !wxStrstr(format, _T("%l")) )
     {
         // use strftime()
     if ( (time != (time_t)-1) && !wxStrstr(format, _T("%l")) )
     {
         // use strftime()
-        tm *tm;
+        struct tm tmstruct;
+        struct tm *tm;
         if ( tz.GetOffset() == -GetTimeZone() )
         {
             // we are working with local time
         if ( tz.GetOffset() == -GetTimeZone() )
         {
             // we are working with local time
-            tm = localtime(&time);
+            tm = wxLocaltime_r(&time, &tmstruct);
 
             // should never happen
 
             // should never happen
-            wxCHECK_MSG( tm, wxEmptyString, _T("localtime() failed") );
+            wxCHECK_MSG( tm, wxEmptyString, _T("wxLocaltime_r() failed") );
         }
         else
         {
         }
         else
         {
@@ -2204,10 +2247,10 @@ wxString wxDateTime::Format(const wxChar *format, const TimeZone& tz) const
             if ( time >= 0 )
 #endif
             {
             if ( time >= 0 )
 #endif
             {
-                tm = gmtime(&time);
+                tm = wxGmtime_r(&time, &tmstruct);
 
                 // should never happen
 
                 // should never happen
-                wxCHECK_MSG( tm, wxEmptyString, _T("gmtime() failed") );
+                wxCHECK_MSG( tm, wxEmptyString, _T("wxGmtime_r() failed") );
             }
             else
             {
             }
             else
             {
@@ -2363,6 +2406,9 @@ wxString wxDateTime::Format(const wxChar *format, const TimeZone& tz) const
                             nLostWeekDays += year++ % 4 ? 1 : 2;
                         }
 
                             nLostWeekDays += year++ % 4 ? 1 : 2;
                         }
 
+                        // Keep year below 2000 so the 2digit year number
+                        // can never match the month or day of the month
+                        if (year>=2000) year-=28;
                         // at any rate, we couldn't go further than 1988 + 9 + 28!
                         wxASSERT_MSG( year < 2030,
                                       _T("logic error in wxDateTime::Format") );
                         // at any rate, we couldn't go further than 1988 + 9 + 28!
                         wxASSERT_MSG( year < 2030,
                                       _T("logic error in wxDateTime::Format") );
@@ -2371,25 +2417,30 @@ wxString wxDateTime::Format(const wxChar *format, const TimeZone& tz) const
                         strYear.Printf(_T("%d"), year);
                         strYear2.Printf(_T("%d"), year % 100);
 
                         strYear.Printf(_T("%d"), year);
                         strYear2.Printf(_T("%d"), year % 100);
 
-                        // find two strings not occurring in format (this is surely
+                        // find four strings not occurring in format (this is surely
                         // not the optimal way of doing it... improvements welcome!)
                         wxString fmt2 = format;
                         // not the optimal way of doing it... improvements welcome!)
                         wxString fmt2 = format;
-                        wxString replacement = (wxChar)-1;
-                        while ( fmt2.Find(replacement) != wxNOT_FOUND )
+                        wxString replacement,replacement2,replacement3,replacement4;
+                        for (int rnr=1; rnr<5 ; rnr++)
                         {
                         {
-                            replacement << (wxChar)-1;
-                        }
+                            wxString r = (wxChar)-rnr;
+                            while ( fmt2.Find(r) != wxNOT_FOUND )
+                            {
+                                r << (wxChar)-rnr;
+                            }
 
 
-                        wxString replacement2 = (wxChar)-2;
-                        while ( fmt2.Find(replacement) != wxNOT_FOUND )
-                        {
-                            replacement << (wxChar)-2;
+                            switch (rnr)
+                            {
+                                case 1: replacement=r; break;
+                                case 2: replacement2=r; break;
+                                case 3: replacement3=r; break;
+                                case 4: replacement4=r; break;
+                            }
                         }
                         }
-
                         // replace all occurrences of year with it
                         bool wasReplaced = fmt2.Replace(strYear, replacement) > 0;
                         // replace all occurrences of year with it
                         bool wasReplaced = fmt2.Replace(strYear, replacement) > 0;
-                        if ( !wasReplaced )
-                            wasReplaced = fmt2.Replace(strYear2, replacement2) > 0;
+                        // evaluation order ensures we always attempt the replacement.
+                        wasReplaced = (fmt2.Replace(strYear2, replacement2) > 0) | wasReplaced ;
 
                         // use strftime() to format the same date but in supported
                         // year
 
                         // use strftime() to format the same date but in supported
                         // year
@@ -2414,11 +2465,17 @@ wxString wxDateTime::Format(const wxChar *format, const TimeZone& tz) const
                                                     &tmAdjusted);
 
                         // now replace the occurrence of 1999 with the real year
                                                     &tmAdjusted);
 
                         // now replace the occurrence of 1999 with the real year
+                        // we do this in two stages to stop the 2 digit year
+                        // matching any substring of the 4 digit year.
+                        // Any day,month hours and minutes components should be safe due
+                        // to ensuring the range of the years.
                         wxString strYearReal, strYearReal2;
                         strYearReal.Printf(_T("%04d"), yearReal);
                         strYearReal2.Printf(_T("%02d"), yearReal % 100);
                         wxString strYearReal, strYearReal2;
                         strYearReal.Printf(_T("%04d"), yearReal);
                         strYearReal2.Printf(_T("%02d"), yearReal % 100);
-                        str.Replace(strYear, strYearReal);
-                        str.Replace(strYear2, strYearReal2);
+                        str.Replace(strYear, replacement3);
+                        str.Replace(strYear2,replacement4);
+                        str.Replace(replacement3, strYearReal);
+                        str.Replace(replacement4, strYearReal2);
 
                         // and replace back all occurrences of replacement string
                         if ( wasReplaced )
 
                         // and replace back all occurrences of replacement string
                         if ( wasReplaced )
@@ -3765,9 +3822,11 @@ const wxChar *wxDateTime::ParseDate(const wxChar *date)
                 }
                 else // may be either day or year
                 {
                 }
                 else // may be either day or year
                 {
+                    // use a leap year if we don't have the year yet to allow
+                    // dates like 2/29/1976 which would be rejected otherwise
                     wxDateTime_t max_days = (wxDateTime_t)(
                         haveMon
                     wxDateTime_t max_days = (wxDateTime_t)(
                         haveMon
-                        ? GetNumOfDaysInMonth(haveYear ? year : Inv_Year, mon)
+                        ? GetNumOfDaysInMonth(haveYear ? year : 1976, mon)
                         : 31
                     );
 
                         : 31
                     );
 
@@ -3920,7 +3979,7 @@ const wxChar *wxDateTime::ParseDate(const wxChar *date)
     {
         wxLogDebug(_T("ParseDate: no day, no weekday hence no date."));
 
     {
         wxLogDebug(_T("ParseDate: no day, no weekday hence no date."));
 
-        return (wxChar *)NULL;
+        return NULL;
     }
 
     if ( haveWDay && (haveMon || haveYear || haveDay) &&
     }
 
     if ( haveWDay && (haveMon || haveYear || haveDay) &&
@@ -3929,7 +3988,7 @@ const wxChar *wxDateTime::ParseDate(const wxChar *date)
         // without adjectives (which we don't support here) the week day only
         // makes sense completely separately or with the full date
         // specification (what would "Wed 1999" mean?)
         // without adjectives (which we don't support here) the week day only
         // makes sense completely separately or with the full date
         // specification (what would "Wed 1999" mean?)
-        return (wxChar *)NULL;
+        return NULL;
     }
 
     if ( !haveWDay && haveYear && !(haveDay && haveMon) )
     }
 
     if ( !haveWDay && haveYear && !(haveDay && haveMon) )
@@ -3959,7 +4018,7 @@ const wxChar *wxDateTime::ParseDate(const wxChar *date)
             // if we give the year, month and day must be given too
             wxLogDebug(_T("ParseDate: day and month should be specified if year is."));
 
             // if we give the year, month and day must be given too
             wxLogDebug(_T("ParseDate: day and month should be specified if year is."));
 
-            return (wxChar *)NULL;
+            return NULL;
         }
     }
 
         }
     }
 
@@ -3975,6 +4034,11 @@ const wxChar *wxDateTime::ParseDate(const wxChar *date)
 
     if ( haveDay )
     {
 
     if ( haveDay )
     {
+        // normally we check the day above but the check is optimistic in case
+        // we find the day before its month/year so we have to redo it now
+        if ( day > GetNumOfDaysInMonth(year, mon) )
+            return NULL;
+
         Set(day, mon, year);
 
         if ( haveWDay )
         Set(day, mon, year);
 
         if ( haveWDay )
@@ -4172,11 +4236,14 @@ wxString wxTimeSpan::Format(const wxChar *format) const
         if ( ch == _T('%') )
         {
             // the start of the format specification of the printf() below
         if ( ch == _T('%') )
         {
             // the start of the format specification of the printf() below
-            wxString fmtPrefix = _T('%');
+            wxString fmtPrefix(_T('%'));
 
             // the number
             long n;
 
 
             // the number
             long n;
 
+            // the number of digits for the format string, 0 if unused
+            unsigned digits = 0;
+
             ch = *++pch;    // get the format spec char
             switch ( ch )
             {
             ch = *++pch;    // get the format spec char
             switch ( ch )
             {
@@ -4211,6 +4278,13 @@ wxString wxTimeSpan::Format(const wxChar *format) const
                     n = GetHours();
                     if ( partBiggest < Part_Hour )
                     {
                     n = GetHours();
                     if ( partBiggest < Part_Hour )
                     {
+                        if ( n < 0 )
+                        {
+                            // the sign has already been taken into account
+                            // when outputting the biggest part
+                            n = -n;
+                        }
+
                         n %= HOURS_PER_DAY;
                     }
                     else
                         n %= HOURS_PER_DAY;
                     }
                     else
@@ -4218,25 +4292,31 @@ wxString wxTimeSpan::Format(const wxChar *format) const
                         partBiggest = Part_Hour;
                     }
 
                         partBiggest = Part_Hour;
                     }
 
-                    fmtPrefix += _T("02");
+                    digits = 2;
                     break;
 
                 case _T('l'):
                     n = GetMilliseconds().ToLong();
                     if ( partBiggest < Part_MSec )
                     {
                     break;
 
                 case _T('l'):
                     n = GetMilliseconds().ToLong();
                     if ( partBiggest < Part_MSec )
                     {
+                        if ( n < 0 )
+                            n = -n;
+
                         n %= 1000;
                     }
                     //else: no need to reset partBiggest to Part_MSec, it is
                     //      the least significant one anyhow
 
                         n %= 1000;
                     }
                     //else: no need to reset partBiggest to Part_MSec, it is
                     //      the least significant one anyhow
 
-                    fmtPrefix += _T("03");
+                    digits = 3;
                     break;
 
                 case _T('M'):
                     n = GetMinutes();
                     if ( partBiggest < Part_Min )
                     {
                     break;
 
                 case _T('M'):
                     n = GetMinutes();
                     if ( partBiggest < Part_Min )
                     {
+                        if ( n < 0 )
+                            n = -n;
+
                         n %= MIN_PER_HOUR;
                     }
                     else
                         n %= MIN_PER_HOUR;
                     }
                     else
@@ -4244,13 +4324,16 @@ wxString wxTimeSpan::Format(const wxChar *format) const
                         partBiggest = Part_Min;
                     }
 
                         partBiggest = Part_Min;
                     }
 
-                    fmtPrefix += _T("02");
+                    digits = 2;
                     break;
 
                 case _T('S'):
                     n = GetSeconds().ToLong();
                     if ( partBiggest < Part_Sec )
                     {
                     break;
 
                 case _T('S'):
                     n = GetSeconds().ToLong();
                     if ( partBiggest < Part_Sec )
                     {
+                        if ( n < 0 )
+                            n = -n;
+
                         n %= SEC_PER_MIN;
                     }
                     else
                         n %= SEC_PER_MIN;
                     }
                     else
@@ -4258,10 +4341,19 @@ wxString wxTimeSpan::Format(const wxChar *format) const
                         partBiggest = Part_Sec;
                     }
 
                         partBiggest = Part_Sec;
                     }
 
-                    fmtPrefix += _T("02");
+                    digits = 2;
                     break;
             }
 
                     break;
             }
 
+            if ( digits )
+            {
+                // negative numbers need one extra position for '-' display
+                if ( n < 0 )
+                    digits++;
+
+                fmtPrefix << _T("0") << digits;
+            }
+
             str += wxString::Format(fmtPrefix + _T("ld"), n);
         }
         else
             str += wxString::Format(fmtPrefix + _T("ld"), n);
         }
         else