------------------------------------------------------------------------------ -- -- -- GNAT RUN-TIME COMPONENTS -- -- -- -- G N A T . C A L E N D A R -- -- -- -- S p e c -- -- -- -- Copyright (C) 1999-2018, Free Software Foundation, Inc. -- -- -- -- 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 3, 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. -- -- -- -- As a special exception under Section 7 of GPL version 3, you are granted -- -- additional permissions described in the GCC Runtime Library Exception, -- -- version 3.1, as published by the Free Software Foundation. -- -- -- -- You should have received a copy of the GNU General Public License and -- -- a copy of the GCC Runtime Library Exception along with this program; -- -- see the files COPYING3 and COPYING.RUNTIME respectively. If not, see -- -- . -- -- -- -- GNAT was originally developed by the GNAT team at New York University. -- -- Extensive contributions were provided by Ada Core Technologies Inc. -- -- -- ------------------------------------------------------------------------------ -- This package extends Ada.Calendar to handle Hour, Minute, Second, -- Second_Duration and Day_Of_Week and Day_In_Year from Calendar.Time. -- Second_Duration precision depends on the target clock precision. -- -- GNAT.Calendar provides the same kind of abstraction found in Ada.Calendar. -- It provides Split and Time_Of to build and split a Time data. And it -- provides accessor functions to get only one of Hour, Minute, Second, -- Second_Duration. Other functions are to access more advanced values like -- Day_Of_Week, Day_In_Year and Week_In_Year. with Ada.Calendar.Formatting; with Interfaces.C; package GNAT.Calendar is type Day_Name is (Monday, Tuesday, Wednesday, Thursday, Friday, Saturday, Sunday); pragma Ordered (Day_Name); subtype Hour_Number is Natural range 0 .. 23; subtype Minute_Number is Natural range 0 .. 59; subtype Second_Number is Natural range 0 .. 59; subtype Second_Duration is Ada.Calendar.Day_Duration range 0.0 .. 1.0; subtype Day_In_Year_Number is Positive range 1 .. 366; subtype Week_In_Year_Number is Positive range 1 .. 53; No_Time : constant Ada.Calendar.Time; -- A constant set to the first date that can be represented by the type -- Time. It can be used to indicate an uninitialized date. function Hour (Date : Ada.Calendar.Time) return Hour_Number; function Minute (Date : Ada.Calendar.Time) return Minute_Number; function Second (Date : Ada.Calendar.Time) return Second_Number; function Sub_Second (Date : Ada.Calendar.Time) return Second_Duration; -- Hour, Minute, Second and Sub_Second returns the complete time data for -- the Date (H:M:S.SS). See Ada.Calendar for Year, Month, Day accessors. -- Second_Duration precision depends on the target clock precision. function Day_Of_Week (Date : Ada.Calendar.Time) return Day_Name; -- Return the day name function Day_In_Year (Date : Ada.Calendar.Time) return Day_In_Year_Number; -- Return the day number in the year. (1st January is day 1 and 31st -- December is day 365 or 366 for leap year). procedure Split (Date : Ada.Calendar.Time; Year : out Ada.Calendar.Year_Number; Month : out Ada.Calendar.Month_Number; Day : out Ada.Calendar.Day_Number; Hour : out Hour_Number; Minute : out Minute_Number; Second : out Second_Number; Sub_Second : out Second_Duration); -- Split a standard Ada.Calendar.Time value in date data (Year, Month, Day) -- and Time data (Hour, Minute, Second, Sub_Second). procedure Split_At_Locale (Date : Ada.Calendar.Time; Year : out Ada.Calendar.Year_Number; Month : out Ada.Calendar.Month_Number; Day : out Ada.Calendar.Day_Number; Hour : out Hour_Number; Minute : out Minute_Number; Second : out Second_Number; Sub_Second : out Second_Duration); -- Split a standard Ada.Calendar.Time value in date data (Year, Month, Day) -- and Time data (Hour, Minute, Second, Sub_Second). This version of Split -- utilizes the time zone and DST bias of the locale (equivalent to Clock). -- Due to this simplified behavior, the implementation does not require -- expensive system calls on targets such as Windows. -- WARNING: Split_At_Locale is no longer aware of historic events and may -- produce inaccurate results over DST changes which occurred in the past. function Time_Of (Year : Ada.Calendar.Year_Number; Month : Ada.Calendar.Month_Number; Day : Ada.Calendar.Day_Number; Hour : Hour_Number; Minute : Minute_Number; Second : Second_Number; Sub_Second : Second_Duration := 0.0) return Ada.Calendar.Time; -- Return an Ada.Calendar.Time data built from the date and time values function Time_Of_At_Locale (Year : Ada.Calendar.Year_Number; Month : Ada.Calendar.Month_Number; Day : Ada.Calendar.Day_Number; Hour : Hour_Number; Minute : Minute_Number; Second : Second_Number; Sub_Second : Second_Duration := 0.0) return Ada.Calendar.Time; -- Return an Ada.Calendar.Time data built from the date and time values. -- This version of Time_Of utilizes the time zone and DST bias of the -- locale (equivalent to Clock). Due to this simplified behavior, the -- implementation does not require expensive system calls on targets such -- as Windows. -- WARNING: Split_At_Locale is no longer aware of historic events and may -- produce inaccurate results over DST changes which occurred in the past. function Week_In_Year (Date : Ada.Calendar.Time) return Week_In_Year_Number; -- Return the week number as defined in ISO 8601. A week always starts on -- a Monday and the first week of a particular year is the one containing -- the first Thursday. A year may have 53 weeks when January 1st is a -- Wednesday and the year is leap or January 1st is a Thursday. Note that -- the last days of December may belong to the first week on the next year -- and conversely, the first days of January may belong to the last week -- of the last year. procedure Year_Week_In_Year (Date : Ada.Calendar.Time; Year : out Ada.Calendar.Year_Number; Week : out Week_In_Year_Number); -- Return the week number as defined in ISO 8601 along with the year in -- which the week occurs. -- C timeval conversion -- C timeval represent a duration (used in Select for example). This -- structure is composed of a number of seconds and a number of micro -- seconds. The timeval structure is not exposed here because its -- definition is target dependent. Interface to C programs is done via a -- pointer to timeval structure. type timeval is private; function To_Duration (T : not null access timeval) return Duration; function To_Timeval (D : Duration) return timeval; private -- This is a dummy declaration that should be the largest possible timeval -- structure of all supported targets. type timeval is array (1 .. 3) of Interfaces.C.long; function Julian_Day (Year : Ada.Calendar.Year_Number; Month : Ada.Calendar.Month_Number; Day : Ada.Calendar.Day_Number) return Integer; -- Compute Julian day number -- -- The code of this function is a modified version of algorithm 199 from -- the Collected Algorithms of the ACM. The author of algorithm 199 is -- Robert G. Tantzen. No_Time : constant Ada.Calendar.Time := Ada.Calendar.Formatting.Time_Of (Ada.Calendar.Year_Number'First, Ada.Calendar.Month_Number'First, Ada.Calendar.Day_Number'First, Time_Zone => 0); -- Use Time_Zone => 0 to be the same binary representation in any timezone end GNAT.Calendar;