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------------------------------------------------------------------------------
-- --
-- GNAT RUN-TIME COMPONENTS --
-- --
-- A D A . C A L E N D A R --
-- --
-- S p e c --
-- --
-- Copyright (C) 1992-2007, Free Software Foundation, Inc. --
-- --
-- This specification is derived from the Ada Reference Manual for use with --
-- GNAT. The copyright notice above, and the license provisions that follow --
-- apply solely to the contents of the part following the private keyword. --
-- --
-- GNAT is free software; you can redistribute it and/or modify it under --
-- terms of the GNU General Public License as published by the Free Soft- --
-- ware Foundation; either version 2, or (at your option) any later ver- --
-- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
-- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
-- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
-- for more details. You should have received a copy of the GNU General --
-- Public License distributed with GNAT; see file COPYING. If not, write --
-- to the Free Software Foundation, 51 Franklin Street, Fifth Floor, --
-- Boston, MA 02110-1301, USA. --
-- --
-- As a special exception, if other files instantiate generics from this --
-- unit, or you link this unit with other files to produce an executable, --
-- this unit does not by itself cause the resulting executable to be --
-- covered by the GNU General Public License. This exception does not --
-- however invalidate any other reasons why the executable file might be --
-- covered by the GNU Public License. --
-- --
-- GNAT was originally developed by the GNAT team at New York University. --
-- Extensive contributions were provided by Ada Core Technologies Inc. --
-- --
------------------------------------------------------------------------------
-- This is the Alpha/VMS version
with System.OS_Primitives;
package Ada.Calendar is
package OSP renames System.OS_Primitives;
type Time is private;
-- Declarations representing limits of allowed local time values. Note
-- that these do NOT constrain the possible stored values of time which
-- may well permit a larger range of times (this is explicitly allowed
-- in Ada 95).
subtype Year_Number is Integer range 1901 .. 2399;
subtype Month_Number is Integer range 1 .. 12;
subtype Day_Number is Integer range 1 .. 31;
subtype Day_Duration is Duration range 0.0 .. 86_400.0;
function Clock return Time;
function Year (Date : Time) return Year_Number;
function Month (Date : Time) return Month_Number;
function Day (Date : Time) return Day_Number;
function Seconds (Date : Time) return Day_Duration;
procedure Split
(Date : Time;
Year : out Year_Number;
Month : out Month_Number;
Day : out Day_Number;
Seconds : out Day_Duration);
function Time_Of
(Year : Year_Number;
Month : Month_Number;
Day : Day_Number;
Seconds : Day_Duration := 0.0) return Time;
function "+" (Left : Time; Right : Duration) return Time;
function "+" (Left : Duration; Right : Time) return Time;
function "-" (Left : Time; Right : Duration) return Time;
function "-" (Left : Time; Right : Time) return Duration;
function "<" (Left, Right : Time) return Boolean;
function "<=" (Left, Right : Time) return Boolean;
function ">" (Left, Right : Time) return Boolean;
function ">=" (Left, Right : Time) return Boolean;
Time_Error : exception;
private
pragma Inline (Clock);
pragma Inline (Year);
pragma Inline (Month);
pragma Inline (Day);
pragma Inline ("+");
pragma Inline ("-");
pragma Inline ("<");
pragma Inline ("<=");
pragma Inline (">");
pragma Inline (">=");
-- Although the units are 100 nanoseconds, for the purpose of better
-- readability, this unit will be called "mili".
Mili : constant := 10_000_000;
Milis_In_Day : constant := 864_000_000_000;
Secs_In_Day : constant := 86_400;
-- Time is represented as the number of 100-nanosecond (ns) units from the
-- system base date and time 1858-11-17 0.0 (the Smithsonian base date and
-- time for the astronomic calendar).
-- The time value stored is typically a UTC value, as provided in standard
-- Unix environments. If this is the case then Split and Time_Of perform
-- required conversions to and from local times.
-- Notwithstanding this definition, Time is not quite the same as OS_Time.
-- Relative Time is positive, whereas relative OS_Time is negative,
-- but this declaration makes for easier conversion.
type Time is new OSP.OS_Time;
Days_In_Month : constant array (Month_Number) of Day_Number :=
(31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31);
Invalid_Time_Zone_Offset : Long_Integer;
pragma Import (C, Invalid_Time_Zone_Offset, "__gnat_invalid_tzoff");
function Is_Leap (Year : Year_Number) return Boolean;
-- Determine whether a given year is leap
-- The following packages provide a target independent interface to the
-- children of Calendar - Arithmetic, Formatting and Time_Zones.
-- NOTE: Delays does not need a target independent interface because
-- VMS already has a target specific file for that package.
package Arithmetic_Operations is
function Add (Date : Time; Days : Long_Integer) return Time;
-- Add a certain number of days to a time value
procedure Difference
(Left : Time;
Right : Time;
Days : out Long_Integer;
Seconds : out Duration;
Leap_Seconds : out Integer);
-- Calculate the difference between two time values in terms of days,
-- seconds and leap seconds elapsed. The leap seconds are not included
-- in the seconds returned. If Left is greater than Right, the returned
-- values are positive, negative otherwise.
function Subtract (Date : Time; Days : Long_Integer) return Time;
-- Subtract a certain number of days from a time value
end Arithmetic_Operations;
package Formatting_Operations is
function Day_Of_Week (Date : Time) return Integer;
-- Determine which day of week Date falls on. The returned values are
-- within the range of 0 .. 6 (Monday .. Sunday).
procedure Split
(Date : Time;
Year : out Year_Number;
Month : out Month_Number;
Day : out Day_Number;
Day_Secs : out Day_Duration;
Hour : out Integer;
Minute : out Integer;
Second : out Integer;
Sub_Sec : out Duration;
Leap_Sec : out Boolean;
Is_Ada_05 : Boolean;
Time_Zone : Long_Integer);
-- Split a time value into its components. Set Is_Ada_05 to use the
-- local time zone (the value in Time_Zone is ignored) when splitting
-- a time value.
function Time_Of
(Year : Year_Number;
Month : Month_Number;
Day : Day_Number;
Day_Secs : Day_Duration;
Hour : Integer;
Minute : Integer;
Second : Integer;
Sub_Sec : Duration;
Leap_Sec : Boolean;
Use_Day_Secs : Boolean;
Is_Ada_05 : Boolean;
Time_Zone : Long_Integer) return Time;
-- Given all the components of a date, return the corresponding time
-- value. Set Use_Day_Secs to use the value in Day_Secs, otherwise the
-- day duration will be calculated from Hour, Minute, Second and Sub_
-- Sec. Set Is_Ada_05 to use the local time zone (the value in formal
-- Time_Zone is ignored) when building a time value and to verify the
-- validity of a requested leap second.
end Formatting_Operations;
package Time_Zones_Operations is
function UTC_Time_Offset (Date : Time) return Long_Integer;
-- Return the offset in seconds from UTC
end Time_Zones_Operations;
end Ada.Calendar;
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