//
// System.TimeZone.cs
//
-// Author: Duncan Mak (duncan@ximian.com)
-// Ajay Kumar Dwivedi (adwiv@yahoo.com)
-// Martin Baulig (martin@gnome.org)
+// Authors:
+// Duncan Mak (duncan@ximian.com)
+// Ajay Kumar Dwivedi (adwiv@yahoo.com)
+// Martin Baulig (martin@gnome.org)
//
// (C) Ximian, Inc.
//
+//
+// Copyright (C) 2004 Novell, Inc (http://www.novell.com)
+//
+// Permission is hereby granted, free of charge, to any person obtaining
+// a copy of this software and associated documentation files (the
+// "Software"), to deal in the Software without restriction, including
+// without limitation the rights to use, copy, modify, merge, publish,
+// distribute, sublicense, and/or sell copies of the Software, and to
+// permit persons to whom the Software is furnished to do so, subject to
+// the following conditions:
+//
+// The above copyright notice and this permission notice shall be
+// included in all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+// LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+// OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+// WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+//
+
using System.Collections;
using System.Globalization;
using System.Runtime.CompilerServices;
-namespace System {
-
+namespace System
+{
[Serializable]
public abstract class TimeZone
{
// Fields
private static TimeZone currentTimeZone;
-
+
// Constructor
protected TimeZone ()
{
}
// Properties
- public static TimeZone CurrentTimeZone
- {
+ public static TimeZone CurrentTimeZone {
get {
if (currentTimeZone == null)
currentTimeZone = new CurrentTimeZone ();
return currentTimeZone;
}
}
-
- public abstract string DaylightName
+
+ internal static void ClearCurrentTimeZone ()
{
+ currentTimeZone = null;
+ }
+
+ public abstract string DaylightName {
get;
}
- public abstract string StandardName
- {
+ public abstract string StandardName {
get;
}
}
public static bool IsDaylightSavingTime (DateTime time, DaylightTime daylightTimes)
- {
+ {
if (daylightTimes == null)
- throw new ArgumentNullException ("daylightTimes");
+ throw new ArgumentNullException ("daylightTimes");
- // If Start == End, then DST is off
- if (daylightTimes.Start.Ticks == daylightTimes.End.Ticks)
- return false;
+ // If Start == End, then DST is off
+ if (daylightTimes.Start.Ticks == daylightTimes.End.Ticks)
+ return false;
- //We are in the northern hemisphere.
+ //We are in the northern hemisphere.
if (daylightTimes.Start.Ticks < daylightTimes.End.Ticks) {
- if (daylightTimes.Start.Ticks < time.Ticks
- && daylightTimes.End.Ticks > time.Ticks)
- return true; // time lies between Start and End
+ if (daylightTimes.Start.Ticks < time.Ticks && daylightTimes.End.Ticks > time.Ticks)
+ return true; // time lies between Start and End
- } else { // We are in the southern hemisphere.
+ }
+ else { // We are in the southern hemisphere.
if (time.Year == daylightTimes.Start.Year && time.Year == daylightTimes.End.Year)
- if (time.Ticks < daylightTimes.End.Ticks
- || time.Ticks > daylightTimes.Start.Ticks)
- return true; // time is less than End OR more than Start
- }
+ if (time.Ticks < daylightTimes.End.Ticks || time.Ticks > daylightTimes.Start.Ticks)
+ return true; // time is less than End OR more than Start
+ }
return false;
- }
-
+ }
+
public virtual DateTime ToLocalTime (DateTime time)
{
- return time + GetUtcOffset (time);
+ DaylightTime dlt = GetDaylightChanges (time.Year);
+ TimeSpan utcOffset = GetUtcOffset (time);
+ if (utcOffset.Ticks > 0) {
+ if (DateTime.MaxValue - utcOffset < time)
+ return DateTime.MaxValue;
+ //} else if (utcOffset.Ticks < 0) {
+ // LAMESPEC: MS.NET fails to check validity here
+ // it may throw ArgumentOutOfRangeException.
+ }
+
+ DateTime local = time.Add (utcOffset);
+ if (dlt.Delta.Ticks == 0)
+ return local;
+
+ // FIXME: check all of the combination of
+ // - basis: local-based or UTC-based
+ // - hemisphere: Northern or Southern
+ // - offset: positive or negative
+
+ // PST should work fine here.
+ if (local < dlt.End && dlt.End.Subtract (dlt.Delta) <= local)
+ return local;
+ if (local >= dlt.Start && dlt.Start.Add (dlt.Delta) > local)
+ return local.Subtract (dlt.Delta);
+
+ TimeSpan localOffset = GetUtcOffset (local);
+ return time.Add (localOffset);
}
public virtual DateTime ToUniversalTime (DateTime time)
{
- return time - GetUtcOffset (time);
+ TimeSpan offset = GetUtcOffset (time);
+
+ if (offset.Ticks < 0) {
+ if (DateTime.MaxValue + offset < time)
+ return DateTime.MaxValue;
+ } else if (offset.Ticks > 0) {
+ if (DateTime.MinValue + offset > time)
+ return DateTime.MinValue;
+ }
+
+ return new DateTime (time.Ticks - offset.Ticks);
}
}
internal class CurrentTimeZone : TimeZone
- {
+ {
// Fields
private static string daylightName;
- private static string standardName;
+ private static string standardName;
- // A yearwise cache of DaylightTime.
- private static Hashtable daylightCache = new Hashtable (1);
-
- // the offset when daylightsaving is not on.
- private static TimeSpan utcOffsetWithOutDLS;
+ // A yearwise cache of DaylightTime.
+ private static Hashtable daylightCache = new Hashtable (1);
- // the offset when daylightsaving is on.
- private static TimeSpan utcOffsetWithDLS;
+ // the offset when daylightsaving is not on.
+ private static TimeSpan utcOffsetWithOutDLS;
- internal enum TimeZoneData {
+ // the offset when daylightsaving is on.
+ private static TimeSpan utcOffsetWithDLS;
+
+ internal enum TimeZoneData
+ {
DaylightSavingStartIdx,
DaylightSavingEndIdx,
UtcOffsetIdx,
AdditionalDaylightOffsetIdx
};
- internal enum TimeZoneNames {
+ internal enum TimeZoneNames
+ {
StandardNameIdx,
DaylightNameIdx
};
// name[0]: name of this timezone when not daylight saving.
// name[1]: name of this timezone when daylight saving.
[MethodImplAttribute(MethodImplOptions.InternalCall)]
- private static extern bool GetTimeZoneData (int year,
- out Int64[] data,
- out string[] names);
+ private static extern bool GetTimeZoneData (int year, out Int64[] data, out string[] names);
// Constructor
internal CurrentTimeZone ()
DateTime now = new DateTime(DateTime.GetNow ());
if (!GetTimeZoneData (now.Year, out data, out names))
- throw new NotSupportedException (Locale.GetText ("Can't get timezone name"));
+ throw new NotSupportedException (Locale.GetText ("Can't get timezone name."));
standardName = Locale.GetText (names[(int)TimeZoneNames.StandardNameIdx]);
daylightName = Locale.GetText (names[(int)TimeZoneNames.DaylightNameIdx]);
utcOffsetWithOutDLS = new TimeSpan (data[(int)TimeZoneData.UtcOffsetIdx]);
- utcOffsetWithDLS = new TimeSpan (data[(int)TimeZoneData.UtcOffsetIdx] + data[(int)TimeZoneData.AdditionalDaylightOffsetIdx]);
+ utcOffsetWithDLS = new TimeSpan (data[(int)TimeZoneData.UtcOffsetIdx]
+ + data[(int)TimeZoneData.AdditionalDaylightOffsetIdx]);
}
// Properties
- public override string DaylightName
- {
- get { return daylightName; }
- }
-
- public override string StandardName
- {
- get { return standardName; }
- }
+ public override string DaylightName {
+ get { return daylightName; }
+ }
+
+ public override string StandardName {
+ get { return standardName; }
+ }
// Methods
[MonoTODO]
public override DaylightTime GetDaylightChanges (int year)
- {
- if (year < 1 || year > 9999)
- throw new ArgumentOutOfRangeException ("year", year + " is not in a range between 1 and 9999.");
-
- if (daylightCache [year] == null) {
- lock (this) {
- if (daylightCache [year] == null) {
- Int64[] data;
- string[] names;
-
- if (!GetTimeZoneData (year, out data, out names))
- throw new ArgumentException (Locale.GetText ("Can't get timezone data for " + year));
-
- DaylightTime dlt = new DaylightTime (new DateTime (data[(int)TimeZoneData.DaylightSavingStartIdx]),
- new DateTime (data[(int)TimeZoneData.DaylightSavingEndIdx]),
- new TimeSpan (data[(int)TimeZoneData.AdditionalDaylightOffsetIdx]));
- daylightCache.Add (year, dlt);
- };
- };
- }
-
- return (DaylightTime) daylightCache [year];
- }
+ {
+ if (year < 1 || year > 9999)
+ throw new ArgumentOutOfRangeException ("year", year +
+ Locale.GetText (" is not in a range between 1 and 9999."));
+
+ lock (daylightCache) {
+ DaylightTime dlt = (DaylightTime) daylightCache [year];
+ if (dlt == null) {
+ Int64[] data;
+ string[] names;
+
+ if (!GetTimeZoneData (year, out data, out names))
+ throw new ArgumentException (Locale.GetText ("Can't get timezone data for " + year));
+
+ dlt = new DaylightTime (new DateTime (data[(int)TimeZoneData.DaylightSavingStartIdx]),
+ new DateTime (data[(int)TimeZoneData.DaylightSavingEndIdx]),
+ new TimeSpan (data[(int)TimeZoneData.AdditionalDaylightOffsetIdx]));
+ daylightCache.Add (year, dlt);
+ }
+ return dlt;
+ }
+ }
public override TimeSpan GetUtcOffset (DateTime time)
{
- if (IsDaylightSavingTime (time))
- return utcOffsetWithDLS;
-
- return utcOffsetWithOutDLS;
- }
+ if (IsDaylightSavingTime (time))
+ return utcOffsetWithDLS;
+
+ return utcOffsetWithOutDLS;
+ }
}
}
projects / mono.git / blobdiff