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106 | package body DCF.Streams.Calendar is
procedure Set_Time (S : out Root_Zipstream_Type'Class; Modification_Time : Ada.Calendar.Time) is
begin
Set_Time (S, Calendar.Convert (Modification_Time));
end Set_Time;
function Get_Time (S : in Root_Zipstream_Type'Class) return Ada.Calendar.Time is
begin
return Calendar.Convert (Get_Time (S));
end Get_Time;
------------------------------------------------
-- Time = DOS Time. Valid through Year 2107 --
------------------------------------------------
procedure Split
(Date : Time;
Year : out Year_Number;
Month : out Month_Number;
Day : out Day_Number;
Seconds : out Day_Duration)
is
D_Date : constant Integer := Integer (Date / 65536);
D_Time : constant Integer := Integer (Date and 65535);
X : Integer;
Hours : Integer;
Minutes : Integer;
Seconds_Only : Integer;
begin
Year := 1980 + D_Date / 512;
X := (D_Date / 32) mod 16;
if X not in Month_Number then -- that is 0, or in 13..15
raise Time_Error;
end if;
Month := X;
X := D_Date mod 32;
if X not in Day_Number then -- that is 0
raise Time_Error;
end if;
Day := X;
Hours := D_Time / 2048;
Minutes := (D_Time / 32) mod 64;
Seconds_Only := 2 * (D_Time mod 32);
if Hours not in 0 .. 23 or Minutes not in 0 .. 59 or Seconds_Only not in 0 .. 59 then
raise Time_Error;
end if;
Seconds := Day_Duration (Hours * 3600 + Minutes * 60 + Seconds_Only);
end Split;
function Time_Of
(Year : Year_Number;
Month : Month_Number;
Day : Day_Number;
Seconds : Day_Duration := 0.0) return Time
is
Year_2 : Integer := Year;
Hours : Unsigned_32;
Minutes : Unsigned_32;
Seconds_Only : Unsigned_32;
Seconds_Day : Unsigned_32;
Result : Unsigned_32;
begin
if Year_2 < 1980 then -- Avoid invalid DOS date
Year_2 := 1980;
end if;
Seconds_Day := Unsigned_32 (Seconds);
Hours := Seconds_Day / 3600;
Minutes := (Seconds_Day / 60) mod 60;
Seconds_Only := Seconds_Day mod 60;
Result :=
-- MSDN formula for encoding:
Unsigned_32 ((Year_2 - 1980) * 512 + Month * 32 + Day) * 65536 -- Date
+
Hours * 2048 +
Minutes * 32 +
Seconds_Only / 2; -- Time
return Time (Result);
end Time_Of;
function ">" (Left, Right : Time) return Boolean is
begin
return Unsigned_32 (Left) > Unsigned_32 (Right);
end ">";
function Convert (Date : in Ada.Calendar.Time) return Time is
Year : Year_Number;
Month : Month_Number;
Day : Day_Number;
Seconds_Day_Dur : Day_Duration;
begin
Split (Date, Year, Month, Day, Seconds_Day_Dur);
return Time_Of (Year, Month, Day, Seconds_Day_Dur);
end Convert;
function Convert (Date : in Time) return Ada.Calendar.Time is
Year : Year_Number;
Month : Month_Number;
Day : Day_Number;
Seconds_Day_Dur : Day_Duration;
begin
Split (Date, Year, Month, Day, Seconds_Day_Dur);
return Time_Of (Year, Month, Day, Seconds_Day_Dur);
end Convert;
end DCF.Streams.Calendar;
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