| ------------------------------------------------------------------------------ |
| -- -- |
| -- GNAT RUN-TIME COMPONENTS -- |
| -- -- |
| -- G N A T . C A L E N D A R -- |
| -- -- |
| -- B o d y -- |
| -- -- |
| -- Copyright (C) 1999-2022, AdaCore -- |
| -- -- |
| -- 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 -- |
| -- <http://www.gnu.org/licenses/>. -- |
| -- -- |
| -- GNAT was originally developed by the GNAT team at New York University. -- |
| -- Extensive contributions were provided by Ada Core Technologies Inc. -- |
| -- -- |
| ------------------------------------------------------------------------------ |
| |
| with Interfaces.C.Extensions; |
| |
| package body GNAT.Calendar is |
| use Ada.Calendar; |
| use Interfaces; |
| |
| ----------------- |
| -- Day_In_Year -- |
| ----------------- |
| |
| function Day_In_Year (Date : Time) return Day_In_Year_Number is |
| Year : Year_Number; |
| Month : Month_Number; |
| Day : Day_Number; |
| Day_Secs : Day_Duration; |
| begin |
| Split (Date, Year, Month, Day, Day_Secs); |
| return Julian_Day (Year, Month, Day) - Julian_Day (Year, 1, 1) + 1; |
| end Day_In_Year; |
| |
| ----------------- |
| -- Day_Of_Week -- |
| ----------------- |
| |
| function Day_Of_Week (Date : Time) return Day_Name is |
| Year : Year_Number; |
| Month : Month_Number; |
| Day : Day_Number; |
| Day_Secs : Day_Duration; |
| begin |
| Split (Date, Year, Month, Day, Day_Secs); |
| return Day_Name'Val ((Julian_Day (Year, Month, Day)) mod 7); |
| end Day_Of_Week; |
| |
| ---------- |
| -- Hour -- |
| ---------- |
| |
| function Hour (Date : Time) return Hour_Number is |
| Year : Year_Number; |
| Month : Month_Number; |
| Day : Day_Number; |
| Hour : Hour_Number; |
| Minute : Minute_Number; |
| Second : Second_Number; |
| Sub_Second : Second_Duration; |
| begin |
| Split (Date, Year, Month, Day, Hour, Minute, Second, Sub_Second); |
| return Hour; |
| end Hour; |
| |
| ---------------- |
| -- Julian_Day -- |
| ---------------- |
| |
| -- Julian_Day is used to by Day_Of_Week and Day_In_Year. Note that this |
| -- implementation is not expensive. |
| |
| function Julian_Day |
| (Year : Year_Number; |
| Month : Month_Number; |
| Day : Day_Number) return Integer |
| is |
| Internal_Year : Integer; |
| Internal_Month : Integer; |
| Internal_Day : Integer; |
| Julian_Date : Integer; |
| C : Integer; |
| Ya : Integer; |
| |
| begin |
| Internal_Year := Integer (Year); |
| Internal_Month := Integer (Month); |
| Internal_Day := Integer (Day); |
| |
| if Internal_Month > 2 then |
| Internal_Month := Internal_Month - 3; |
| else |
| Internal_Month := Internal_Month + 9; |
| Internal_Year := Internal_Year - 1; |
| end if; |
| |
| C := Internal_Year / 100; |
| Ya := Internal_Year - (100 * C); |
| |
| Julian_Date := (146_097 * C) / 4 + |
| (1_461 * Ya) / 4 + |
| (153 * Internal_Month + 2) / 5 + |
| Internal_Day + 1_721_119; |
| |
| return Julian_Date; |
| end Julian_Day; |
| |
| ------------ |
| -- Minute -- |
| ------------ |
| |
| function Minute (Date : Time) return Minute_Number is |
| Year : Year_Number; |
| Month : Month_Number; |
| Day : Day_Number; |
| Hour : Hour_Number; |
| Minute : Minute_Number; |
| Second : Second_Number; |
| Sub_Second : Second_Duration; |
| begin |
| Split (Date, Year, Month, Day, Hour, Minute, Second, Sub_Second); |
| return Minute; |
| end Minute; |
| |
| ------------ |
| -- Second -- |
| ------------ |
| |
| function Second (Date : Time) return Second_Number is |
| Year : Year_Number; |
| Month : Month_Number; |
| Day : Day_Number; |
| Hour : Hour_Number; |
| Minute : Minute_Number; |
| Second : Second_Number; |
| Sub_Second : Second_Duration; |
| begin |
| Split (Date, Year, Month, Day, Hour, Minute, Second, Sub_Second); |
| return Second; |
| end Second; |
| |
| ----------- |
| -- Split -- |
| ----------- |
| |
| procedure Split |
| (Date : Time; |
| Year : out Year_Number; |
| Month : out Month_Number; |
| Day : out Day_Number; |
| Hour : out Hour_Number; |
| Minute : out Minute_Number; |
| Second : out Second_Number; |
| Sub_Second : out Second_Duration) |
| is |
| Day_Secs : Day_Duration; |
| Secs : Natural; |
| |
| begin |
| Split (Date, Year, Month, Day, Day_Secs); |
| |
| Secs := (if Day_Secs = 0.0 then 0 else Natural (Day_Secs - 0.5)); |
| Sub_Second := Second_Duration (Day_Secs - Day_Duration (Secs)); |
| Hour := Hour_Number (Secs / 3_600); |
| Secs := Secs mod 3_600; |
| Minute := Minute_Number (Secs / 60); |
| Second := Second_Number (Secs mod 60); |
| end Split; |
| |
| --------------------- |
| -- Split_At_Locale -- |
| --------------------- |
| |
| procedure Split_At_Locale |
| (Date : Time; |
| Year : out Year_Number; |
| Month : out Month_Number; |
| Day : out Day_Number; |
| Hour : out Hour_Number; |
| Minute : out Minute_Number; |
| Second : out Second_Number; |
| Sub_Second : out Second_Duration) |
| is |
| procedure Ada_Calendar_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; |
| Use_TZ : Boolean; |
| Is_Historic : Boolean; |
| Time_Zone : Long_Integer); |
| pragma Import (Ada, Ada_Calendar_Split, "__gnat_split"); |
| |
| Ds : Day_Duration; |
| Le : Boolean; |
| |
| begin |
| -- Even though the input time zone is UTC (0), the flag Use_TZ will |
| -- ensure that Split picks up the local time zone. ???But Use_TZ is |
| -- False below, and anyway, Use_TZ has no effect if Time_Zone is 0. |
| |
| Ada_Calendar_Split |
| (Date => Date, |
| Year => Year, |
| Month => Month, |
| Day => Day, |
| Day_Secs => Ds, |
| Hour => Hour, |
| Minute => Minute, |
| Second => Second, |
| Sub_Sec => Sub_Second, |
| Leap_Sec => Le, |
| Use_TZ => False, |
| Is_Historic => False, |
| Time_Zone => 0); |
| end Split_At_Locale; |
| |
| ---------------- |
| -- Sub_Second -- |
| ---------------- |
| |
| function Sub_Second (Date : Time) return Second_Duration is |
| Year : Year_Number; |
| Month : Month_Number; |
| Day : Day_Number; |
| Hour : Hour_Number; |
| Minute : Minute_Number; |
| Second : Second_Number; |
| Sub_Second : Second_Duration; |
| begin |
| Split (Date, Year, Month, Day, Hour, Minute, Second, Sub_Second); |
| return Sub_Second; |
| end Sub_Second; |
| |
| ------------- |
| -- Time_Of -- |
| ------------- |
| |
| function Time_Of |
| (Year : Year_Number; |
| Month : Month_Number; |
| Day : Day_Number; |
| Hour : Hour_Number; |
| Minute : Minute_Number; |
| Second : Second_Number; |
| Sub_Second : Second_Duration := 0.0) return Time |
| is |
| Day_Secs : constant Day_Duration := |
| Day_Duration (Hour * 3_600) + |
| Day_Duration (Minute * 60) + |
| Day_Duration (Second) + |
| Sub_Second; |
| begin |
| return Time_Of (Year, Month, Day, Day_Secs); |
| end Time_Of; |
| |
| ----------------------- |
| -- Time_Of_At_Locale -- |
| ----------------------- |
| |
| function Time_Of_At_Locale |
| (Year : Year_Number; |
| Month : Month_Number; |
| Day : Day_Number; |
| Hour : Hour_Number; |
| Minute : Minute_Number; |
| Second : Second_Number; |
| Sub_Second : Second_Duration := 0.0) return Time |
| is |
| function Ada_Calendar_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; |
| Use_TZ : Boolean; |
| Is_Historic : Boolean; |
| Time_Zone : Long_Integer) return Time; |
| pragma Import (Ada, Ada_Calendar_Time_Of, "__gnat_time_of"); |
| |
| begin |
| -- Even though the input time zone is UTC (0), the flag Use_TZ will |
| -- ensure that Split picks up the local time zone. ???But there is no |
| -- call to Split here. |
| |
| return |
| Ada_Calendar_Time_Of |
| (Year => Year, |
| Month => Month, |
| Day => Day, |
| Day_Secs => 0.0, |
| Hour => Hour, |
| Minute => Minute, |
| Second => Second, |
| Sub_Sec => Sub_Second, |
| Leap_Sec => False, |
| Use_Day_Secs => False, |
| Use_TZ => False, |
| Is_Historic => False, |
| Time_Zone => 0); |
| end Time_Of_At_Locale; |
| |
| ----------------- |
| -- To_Duration -- |
| ----------------- |
| |
| function To_Duration (T : not null access timeval) return Duration is |
| |
| procedure timeval_to_duration |
| (T : not null access timeval; |
| sec : not null access C.Extensions.long_long; |
| usec : not null access C.long); |
| pragma Import (C, timeval_to_duration, "__gnat_timeval_to_duration"); |
| |
| Micro : constant := 10**6; |
| sec : aliased C.Extensions.long_long; |
| usec : aliased C.long; |
| |
| begin |
| timeval_to_duration (T, sec'Access, usec'Access); |
| pragma Annotate (CodePeer, Modified, sec); |
| pragma Annotate (CodePeer, Modified, usec); |
| |
| return Duration (sec) + Duration (usec) / Micro; |
| end To_Duration; |
| |
| ---------------- |
| -- To_Timeval -- |
| ---------------- |
| |
| function To_Timeval (D : Duration) return timeval is |
| |
| procedure duration_to_timeval |
| (Sec : C.Extensions.long_long; |
| Usec : C.long; |
| T : not null access timeval); |
| pragma Import (C, duration_to_timeval, "__gnat_duration_to_timeval"); |
| |
| Micro : constant := 10**6; |
| Result : aliased timeval; |
| sec : C.Extensions.long_long; |
| usec : C.long; |
| |
| begin |
| if D = 0.0 then |
| sec := 0; |
| usec := 0; |
| else |
| sec := C.Extensions.long_long (D - 0.5); |
| usec := C.long ((D - Duration (sec)) * Micro - 0.5); |
| end if; |
| |
| duration_to_timeval (sec, usec, Result'Access); |
| |
| return Result; |
| end To_Timeval; |
| |
| ------------------ |
| -- Week_In_Year -- |
| ------------------ |
| |
| function Week_In_Year (Date : Time) return Week_In_Year_Number is |
| Year : Year_Number; |
| Week : Week_In_Year_Number; |
| begin |
| Year_Week_In_Year (Date, Year, Week); |
| return Week; |
| end Week_In_Year; |
| |
| ----------------------- |
| -- Year_Week_In_Year -- |
| ----------------------- |
| |
| procedure Year_Week_In_Year |
| (Date : Time; |
| Year : out Year_Number; |
| Week : out Week_In_Year_Number) |
| is |
| Month : Month_Number; |
| Day : Day_Number; |
| Hour : Hour_Number; |
| Minute : Minute_Number; |
| Second : Second_Number; |
| Sub_Second : Second_Duration; |
| Jan_1 : Day_Name; |
| Shift : Week_In_Year_Number; |
| Start_Week : Week_In_Year_Number; |
| |
| function Is_Leap (Year : Year_Number) return Boolean; |
| -- Return True if Year denotes a leap year. Leap centennial years are |
| -- properly handled. |
| |
| function Jan_1_Day_Of_Week |
| (Jan_1 : Day_Name; |
| Year : Year_Number; |
| Last_Year : Boolean := False; |
| Next_Year : Boolean := False) return Day_Name; |
| -- Given the weekday of January 1 in Year, determine the weekday on |
| -- which January 1 fell last year or will fall next year as set by |
| -- the two flags. This routine does not call Time_Of or Split. |
| |
| function Last_Year_Has_53_Weeks |
| (Jan_1 : Day_Name; |
| Year : Year_Number) return Boolean; |
| -- Given the weekday of January 1 in Year, determine whether last year |
| -- has 53 weeks. A False value implies that the year has 52 weeks. |
| |
| ------------- |
| -- Is_Leap -- |
| ------------- |
| |
| function Is_Leap (Year : Year_Number) return Boolean is |
| begin |
| if Year mod 400 = 0 then |
| return True; |
| elsif Year mod 100 = 0 then |
| return False; |
| else |
| return Year mod 4 = 0; |
| end if; |
| end Is_Leap; |
| |
| ----------------------- |
| -- Jan_1_Day_Of_Week -- |
| ----------------------- |
| |
| function Jan_1_Day_Of_Week |
| (Jan_1 : Day_Name; |
| Year : Year_Number; |
| Last_Year : Boolean := False; |
| Next_Year : Boolean := False) return Day_Name |
| is |
| Shift : Integer := 0; |
| |
| begin |
| if Last_Year then |
| Shift := (if Is_Leap (Year - 1) then -2 else -1); |
| elsif Next_Year then |
| Shift := (if Is_Leap (Year) then 2 else 1); |
| end if; |
| |
| return Day_Name'Val ((Day_Name'Pos (Jan_1) + Shift) mod 7); |
| end Jan_1_Day_Of_Week; |
| |
| ---------------------------- |
| -- Last_Year_Has_53_Weeks -- |
| ---------------------------- |
| |
| function Last_Year_Has_53_Weeks |
| (Jan_1 : Day_Name; |
| Year : Year_Number) return Boolean |
| is |
| Last_Jan_1 : constant Day_Name := |
| Jan_1_Day_Of_Week (Jan_1, Year, Last_Year => True); |
| |
| begin |
| -- These two cases are illustrated in the table below |
| |
| return |
| Last_Jan_1 = Thursday |
| or else (Last_Jan_1 = Wednesday and then Is_Leap (Year - 1)); |
| end Last_Year_Has_53_Weeks; |
| |
| -- Start of processing for Week_In_Year |
| |
| begin |
| Split (Date, Year, Month, Day, Hour, Minute, Second, Sub_Second); |
| |
| -- According to ISO 8601, the first week of year Y is the week that |
| -- contains the first Thursday in year Y. The following table contains |
| -- all possible combinations of years and weekdays along with examples. |
| |
| -- +-------+------+-------+---------+ |
| -- | Jan 1 | Leap | Weeks | Example | |
| -- +-------+------+-------+---------+ |
| -- | Mon | No | 52 | 2007 | |
| -- +-------+------+-------+---------+ |
| -- | Mon | Yes | 52 | 1996 | |
| -- +-------+------+-------+---------+ |
| -- | Tue | No | 52 | 2002 | |
| -- +-------+------+-------+---------+ |
| -- | Tue | Yes | 52 | 1980 | |
| -- +-------+------+-------+---------+ |
| -- | Wed | No | 52 | 2003 | |
| -- +-------+------#########---------+ |
| -- | Wed | Yes # 53 # 1992 | |
| -- +-------+------#-------#---------+ |
| -- | Thu | No # 53 # 1998 | |
| -- +-------+------#-------#---------+ |
| -- | Thu | Yes # 53 # 2004 | |
| -- +-------+------#########---------+ |
| -- | Fri | No | 52 | 1999 | |
| -- +-------+------+-------+---------+ |
| -- | Fri | Yes | 52 | 1988 | |
| -- +-------+------+-------+---------+ |
| -- | Sat | No | 52 | 1994 | |
| -- +-------+------+-------+---------+ |
| -- | Sat | Yes | 52 | 1972 | |
| -- +-------+------+-------+---------+ |
| -- | Sun | No | 52 | 1995 | |
| -- +-------+------+-------+---------+ |
| -- | Sun | Yes | 52 | 1956 | |
| -- +-------+------+-------+---------+ |
| |
| -- A small optimization, the input date is January 1. Note that this |
| -- is a key day since it determines the number of weeks and is used |
| -- when special casing the first week of January and the last week of |
| -- December. |
| |
| Jan_1 := Day_Of_Week (if Day = 1 and then Month = 1 |
| then Date |
| else (Time_Of (Year, 1, 1, 0.0))); |
| |
| -- Special cases for January |
| |
| if Month = 1 then |
| |
| -- Special case 1: January 1, 2 and 3. These three days may belong |
| -- to last year's last week which can be week number 52 or 53. |
| |
| -- +-----+-----+-----+=====+-----+-----+-----+ |
| -- | Mon | Tue | Wed # Thu # Fri | Sat | Sun | |
| -- +-----+-----+-----+-----+-----+-----+-----+ |
| -- | 26 | 27 | 28 # 29 # 30 | 31 | 1 | |
| -- +-----+-----+-----+-----+-----+-----+-----+ |
| -- | 27 | 28 | 29 # 30 # 31 | 1 | 2 | |
| -- +-----+-----+-----+-----+-----+-----+-----+ |
| -- | 28 | 29 | 30 # 31 # 1 | 2 | 3 | |
| -- +-----+-----+-----+=====+-----+-----+-----+ |
| |
| if (Day = 1 and then Jan_1 in Friday .. Sunday) |
| or else |
| (Day = 2 and then Jan_1 in Friday .. Saturday) |
| or else |
| (Day = 3 and then Jan_1 = Friday) |
| then |
| Week := (if Last_Year_Has_53_Weeks (Jan_1, Year) then 53 else 52); |
| |
| -- January 1, 2 and 3 belong to the previous year |
| |
| Year := Year - 1; |
| return; |
| |
| -- Special case 2: January 1, 2, 3, 4, 5, 6 and 7 of the first week |
| |
| -- +-----+-----+-----+=====+-----+-----+-----+ |
| -- | Mon | Tue | Wed # Thu # Fri | Sat | Sun | |
| -- +-----+-----+-----+-----+-----+-----+-----+ |
| -- | 29 | 30 | 31 # 1 # 2 | 3 | 4 | |
| -- +-----+-----+-----+-----+-----+-----+-----+ |
| -- | 30 | 31 | 1 # 2 # 3 | 4 | 5 | |
| -- +-----+-----+-----+-----+-----+-----+-----+ |
| -- | 31 | 1 | 2 # 3 # 4 | 5 | 6 | |
| -- +-----+-----+-----+-----+-----+-----+-----+ |
| -- | 1 | 2 | 3 # 4 # 5 | 6 | 7 | |
| -- +-----+-----+-----+=====+-----+-----+-----+ |
| |
| elsif (Day <= 4 and then Jan_1 in Monday .. Thursday) |
| or else |
| (Day = 5 and then Jan_1 in Monday .. Wednesday) |
| or else |
| (Day = 6 and then Jan_1 in Monday .. Tuesday) |
| or else |
| (Day = 7 and then Jan_1 = Monday) |
| then |
| Week := 1; |
| return; |
| end if; |
| |
| -- Month other than 1 |
| |
| -- Special case 3: December 29, 30 and 31. These days may belong to |
| -- next year's first week. |
| |
| -- +-----+-----+-----+=====+-----+-----+-----+ |
| -- | Mon | Tue | Wed # Thu # Fri | Sat | Sun | |
| -- +-----+-----+-----+-----+-----+-----+-----+ |
| -- | 29 | 30 | 31 # 1 # 2 | 3 | 4 | |
| -- +-----+-----+-----+-----+-----+-----+-----+ |
| -- | 30 | 31 | 1 # 2 # 3 | 4 | 5 | |
| -- +-----+-----+-----+-----+-----+-----+-----+ |
| -- | 31 | 1 | 2 # 3 # 4 | 5 | 6 | |
| -- +-----+-----+-----+=====+-----+-----+-----+ |
| |
| elsif Month = 12 and then Day > 28 then |
| declare |
| Next_Jan_1 : constant Day_Name := |
| Jan_1_Day_Of_Week (Jan_1, Year, Next_Year => True); |
| begin |
| if (Day = 29 and then Next_Jan_1 = Thursday) |
| or else |
| (Day = 30 and then Next_Jan_1 in Wednesday .. Thursday) |
| or else |
| (Day = 31 and then Next_Jan_1 in Tuesday .. Thursday) |
| then |
| Year := Year + 1; |
| Week := 1; |
| return; |
| end if; |
| end; |
| end if; |
| |
| -- Determine the week from which to start counting. If January 1 does |
| -- not belong to the first week of the input year, then the next week |
| -- is the first week. |
| |
| Start_Week := (if Jan_1 in Friday .. Sunday then 1 else 2); |
| |
| -- At this point all special combinations have been accounted for and |
| -- the proper start week has been found. Since January 1 may not fall |
| -- on a Monday, shift 7 - Day_Name'Pos (Jan_1). This action ensures an |
| -- origin which falls on Monday. |
| |
| Shift := 7 - Day_Name'Pos (Jan_1); |
| Week := Start_Week + (Day_In_Year (Date) - Shift - 1) / 7; |
| end Year_Week_In_Year; |
| |
| end GNAT.Calendar; |