------------------------------------------------------------------------------ -- -- -- GNAT RUN-TIME COMPONENTS -- -- -- -- A D A . C A L E N D A R -- -- -- -- S p e c -- -- -- -- Copyright (C) 1992-2006, 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. -- -- -- ------------------------------------------------------------------------------ package Ada.Calendar is 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 .. 2099; 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; -- GNAT Note: Normally when procedure Split is called on a Time value -- result of a call to function Time_Of, the out parameters of procedure -- Split are identical to the in parameters of function Time_Of. However, -- when a non-existent time of day is specified, the values for Seconds -- may or may not be different. This may happen when Daylight Saving Time -- (DST) is in effect, on the day when switching to DST, if Seconds -- specifies a time of day in the hour that does not exist. For example, -- in New York: -- -- Time_Of (Year => 1998, Month => 4, Day => 5, Seconds => 10740.0) -- -- will return a Time value T. If Split is called on T, the resulting -- Seconds may be 14340.0 (3:59:00) instead of 10740.0 (2:59:00 being -- a time that not exist). 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 (">="); -- Time is represented as a signed duration from the base point which is -- what Unix calls the EPOCH (i.e. 12 midnight (24:00:00), Dec 31st, 1969, -- or if you prefer 0:00:00 on Jan 1st, 1970). Since Ada allows dates -- before this EPOCH value, the stored duration value may be negative. -- The time value stored is typically a GMT 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. The range of times that -- can be stored in Time values depends on the declaration of the type -- Duration, which must at least cover the required Ada range represented -- by the declaration of Year_Number, but may be larger (we take full -- advantage of the new permission in Ada 95 to store time values outside -- the range that would be acceptable to Split). The Duration type is a -- real value representing a time interval in seconds. type Time is new Duration; -- The following package provides handling of leap seconds. It is -- used by Ada.Calendar.Arithmetic and Ada.Calendar.Formatting, both -- Ada 2005 children of Ada.Calendar. package Leap_Sec_Ops is After_Last_Leap : constant Time := Time'Last; -- Bigger by far than any leap second value. Not within range of -- Ada.Calendar specified dates. procedure Cumulative_Leap_Secs (Start_Date : Time; End_Date : Time; Leaps_Between : out Duration; Next_Leap_Sec : out Time); -- Leaps_Between is the sum of the leap seconds that have occured -- on or after Start_Date and before (strictly before) End_Date. -- Next_Leap_Sec represents the next leap second occurence on or -- after End_Date. If there are no leaps seconds after End_Date, -- After_Last_Leap is returned. This does not provide info about -- the next leap second (pos/neg or ?). After_Last_Leap can be used -- as End_Date to count all the leap seconds that have occured on -- or after Start_Date. -- -- Important Notes: any fractional parts of Start_Date and End_Date -- are discarded before the calculations are done. For instance: if -- 113 seconds is a leap second (it isn't) and 113.5 is input as an -- End_Date, the leap second at 113 will not be counted in -- Leaps_Between, but it will be returned as Next_Leap_Sec. Thus, if -- the caller wants to know if the End_Date is a leap second, the -- comparison should be: -- -- End_Date >= Next_Leap_Sec; -- -- After_Last_Leap is designed so that this comparison works without -- having to first check if Next_Leap_Sec is a valid leap second. function All_Leap_Seconds return Duration; -- Returns the sum off all of the leap seoncds. end Leap_Sec_Ops; procedure Split_With_Offset (Date : Time; Year : out Year_Number; Month : out Month_Number; Day : out Day_Number; Seconds : out Day_Duration; Offset : out Long_Integer); -- Split_W_Offset has the same spec as Split with the addition of an -- offset value which give the offset of the local time zone from UTC -- at the input Date. This value comes for free during the implementation -- of Split and is needed by UTC_Time_Offset. The returned Offset time -- is straight from the C tm struct and is in seconds. If the system -- dependent code has no way to find the offset it will return the value -- Invalid_TZ_Offset declared below. Otherwise no checking is done, so -- it is up to the user to check both for Invalid_TZ_Offset and otherwise -- for a value that is acceptable. Invalid_TZ_Offset : Long_Integer; pragma Import (C, Invalid_TZ_Offset, "__gnat_invalid_tzoff"); end Ada.Calendar;