From 554fd8c5195424bdbcabf5de30fdc183aba391bd Mon Sep 17 00:00:00 2001 From: upstream source tree Date: Sun, 15 Mar 2015 20:14:05 -0400 Subject: obtained gcc-4.6.4.tar.bz2 from upstream website; verified gcc-4.6.4.tar.bz2.sig; imported gcc-4.6.4 source tree from verified upstream tarball. downloading a git-generated archive based on the 'upstream' tag should provide you with a source tree that is binary identical to the one extracted from the above tarball. if you have obtained the source via the command 'git clone', however, do note that line-endings of files in your working directory might differ from line-endings of the respective files in the upstream repository. --- gcc/ada/a-calend.adb | 1523 ++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 1523 insertions(+) create mode 100644 gcc/ada/a-calend.adb (limited to 'gcc/ada/a-calend.adb') diff --git a/gcc/ada/a-calend.adb b/gcc/ada/a-calend.adb new file mode 100644 index 000000000..dd500f436 --- /dev/null +++ b/gcc/ada/a-calend.adb @@ -0,0 +1,1523 @@ +------------------------------------------------------------------------------ +-- -- +-- GNAT RUN-TIME COMPONENTS -- +-- -- +-- A D A . C A L E N D A R -- +-- -- +-- B o d y -- +-- -- +-- Copyright (C) 1992-2009, 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. -- +-- -- +------------------------------------------------------------------------------ + +with Ada.Unchecked_Conversion; + +with System.OS_Primitives; + +package body Ada.Calendar is + + -------------------------- + -- Implementation Notes -- + -------------------------- + + -- In complex algorithms, some variables of type Ada.Calendar.Time carry + -- suffix _S or _N to denote units of seconds or nanoseconds. + -- + -- Because time is measured in different units and from different origins + -- on various targets, a system independent model is incorporated into + -- Ada.Calendar. The idea behind the design is to encapsulate all target + -- dependent machinery in a single package, thus providing a uniform + -- interface to all existing and any potential children. + + -- package Ada.Calendar + -- procedure Split (5 parameters) -------+ + -- | Call from local routine + -- private | + -- package Formatting_Operations | + -- procedure Split (11 parameters) <--+ + -- end Formatting_Operations | + -- end Ada.Calendar | + -- | + -- package Ada.Calendar.Formatting | Call from child routine + -- procedure Split (9 or 10 parameters) -+ + -- end Ada.Calendar.Formatting + + -- The behaviour of the interfacing routines is controlled via various + -- flags. All new Ada 2005 types from children of Ada.Calendar are + -- emulated by a similar type. For instance, type Day_Number is replaced + -- by Integer in various routines. One ramification of this model is that + -- the caller site must perform validity checks on returned results. + -- The end result of this model is the lack of target specific files per + -- child of Ada.Calendar (a-calfor, a-calfor-vms, a-calfor-vxwors, etc). + + ----------------------- + -- Local Subprograms -- + ----------------------- + + procedure Check_Within_Time_Bounds (T : Time_Rep); + -- Ensure that a time representation value falls withing the bounds of Ada + -- time. Leap seconds support is taken into account. + + procedure Cumulative_Leap_Seconds + (Start_Date : Time_Rep; + End_Date : Time_Rep; + Elapsed_Leaps : out Natural; + Next_Leap : out Time_Rep); + -- Elapsed_Leaps is the sum of the leap seconds that have occurred on or + -- after Start_Date and before (strictly before) End_Date. Next_Leap_Sec + -- represents the next leap second occurrence on or after End_Date. If + -- there are no leaps seconds after End_Date, End_Of_Time is returned. + -- End_Of_Time can be used as End_Date to count all the leap seconds that + -- have occurred on or after Start_Date. + -- + -- Note: Any sub seconds 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 Duration_To_Time_Rep is + new Ada.Unchecked_Conversion (Duration, Time_Rep); + -- Convert a duration value into a time representation value + + function Time_Rep_To_Duration is + new Ada.Unchecked_Conversion (Time_Rep, Duration); + -- Convert a time representation value into a duration value + + ----------------- + -- Local Types -- + ----------------- + + -- An integer time duration. The type is used whenever a positive elapsed + -- duration is needed, for instance when splitting a time value. Here is + -- how Time_Rep and Time_Dur are related: + + -- 'First Ada_Low Ada_High 'Last + -- Time_Rep: +-------+------------------------+---------+ + -- Time_Dur: +------------------------+---------+ + -- 0 'Last + + type Time_Dur is range 0 .. 2 ** 63 - 1; + + -------------------------- + -- Leap seconds control -- + -------------------------- + + Flag : Integer; + pragma Import (C, Flag, "__gl_leap_seconds_support"); + -- This imported value is used to determine whether the compilation had + -- binder flag "-y" present which enables leap seconds. A value of zero + -- signifies no leap seconds support while a value of one enables the + -- support. + + Leap_Support : constant Boolean := Flag = 1; + -- The above flag controls the usage of leap seconds in all Ada.Calendar + -- routines. + + Leap_Seconds_Count : constant Natural := 24; + + --------------------- + -- Local Constants -- + --------------------- + + Ada_Min_Year : constant Year_Number := Year_Number'First; + Secs_In_Four_Years : constant := (3 * 365 + 366) * Secs_In_Day; + Secs_In_Non_Leap_Year : constant := 365 * Secs_In_Day; + Nanos_In_Four_Years : constant := Secs_In_Four_Years * Nano; + + -- Lower and upper bound of Ada time. The zero (0) value of type Time is + -- positioned at year 2150. Note that the lower and upper bound account + -- for the non-leap centennial years. + + Ada_Low : constant Time_Rep := -(61 * 366 + 188 * 365) * Nanos_In_Day; + Ada_High : constant Time_Rep := (60 * 366 + 190 * 365) * Nanos_In_Day; + + -- Even though the upper bound of time is 2399-12-31 23:59:59.999999999 + -- UTC, it must be increased to include all leap seconds. + + Ada_High_And_Leaps : constant Time_Rep := + Ada_High + Time_Rep (Leap_Seconds_Count) * Nano; + + -- Two constants used in the calculations of elapsed leap seconds. + -- End_Of_Time is later than Ada_High in time zone -28. Start_Of_Time + -- is earlier than Ada_Low in time zone +28. + + End_Of_Time : constant Time_Rep := + Ada_High + Time_Rep (3) * Nanos_In_Day; + Start_Of_Time : constant Time_Rep := + Ada_Low - Time_Rep (3) * Nanos_In_Day; + + -- The Unix lower time bound expressed as nanoseconds since the + -- start of Ada time in UTC. + + Unix_Min : constant Time_Rep := + Ada_Low + Time_Rep (17 * 366 + 52 * 365) * Nanos_In_Day; + + Epoch_Offset : constant Time_Rep := (136 * 365 + 44 * 366) * Nanos_In_Day; + -- The difference between 2150-1-1 UTC and 1970-1-1 UTC expressed in + -- nanoseconds. Note that year 2100 is non-leap. + + Cumulative_Days_Before_Month : + constant array (Month_Number) of Natural := + (0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334); + + -- The following table contains the hard time values of all existing leap + -- seconds. The values are produced by the utility program xleaps.adb. + + Leap_Second_Times : constant array (1 .. Leap_Seconds_Count) of Time_Rep := + (-5601484800000000000, + -5585587199000000000, + -5554051198000000000, + -5522515197000000000, + -5490979196000000000, + -5459356795000000000, + -5427820794000000000, + -5396284793000000000, + -5364748792000000000, + -5317487991000000000, + -5285951990000000000, + -5254415989000000000, + -5191257588000000000, + -5112287987000000000, + -5049129586000000000, + -5017593585000000000, + -4970332784000000000, + -4938796783000000000, + -4907260782000000000, + -4859827181000000000, + -4812566380000000000, + -4765132779000000000, + -4544207978000000000, + -4449513577000000000); + + --------- + -- "+" -- + --------- + + function "+" (Left : Time; Right : Duration) return Time is + pragma Unsuppress (Overflow_Check); + Left_N : constant Time_Rep := Time_Rep (Left); + begin + return Time (Left_N + Duration_To_Time_Rep (Right)); + exception + when Constraint_Error => + raise Time_Error; + end "+"; + + function "+" (Left : Duration; Right : Time) return Time is + begin + return Right + Left; + end "+"; + + --------- + -- "-" -- + --------- + + function "-" (Left : Time; Right : Duration) return Time is + pragma Unsuppress (Overflow_Check); + Left_N : constant Time_Rep := Time_Rep (Left); + begin + return Time (Left_N - Duration_To_Time_Rep (Right)); + exception + when Constraint_Error => + raise Time_Error; + end "-"; + + function "-" (Left : Time; Right : Time) return Duration is + pragma Unsuppress (Overflow_Check); + + -- The bounds of type Duration expressed as time representations + + Dur_Low : constant Time_Rep := Duration_To_Time_Rep (Duration'First); + Dur_High : constant Time_Rep := Duration_To_Time_Rep (Duration'Last); + + Res_N : Time_Rep; + + begin + Res_N := Time_Rep (Left) - Time_Rep (Right); + + -- Due to the extended range of Ada time, "-" is capable of producing + -- results which may exceed the range of Duration. In order to prevent + -- the generation of bogus values by the Unchecked_Conversion, we apply + -- the following check. + + if Res_N < Dur_Low + or else Res_N > Dur_High + then + raise Time_Error; + end if; + + return Time_Rep_To_Duration (Res_N); + exception + when Constraint_Error => + raise Time_Error; + end "-"; + + --------- + -- "<" -- + --------- + + function "<" (Left, Right : Time) return Boolean is + begin + return Time_Rep (Left) < Time_Rep (Right); + end "<"; + + ---------- + -- "<=" -- + ---------- + + function "<=" (Left, Right : Time) return Boolean is + begin + return Time_Rep (Left) <= Time_Rep (Right); + end "<="; + + --------- + -- ">" -- + --------- + + function ">" (Left, Right : Time) return Boolean is + begin + return Time_Rep (Left) > Time_Rep (Right); + end ">"; + + ---------- + -- ">=" -- + ---------- + + function ">=" (Left, Right : Time) return Boolean is + begin + return Time_Rep (Left) >= Time_Rep (Right); + end ">="; + + ------------------------------ + -- Check_Within_Time_Bounds -- + ------------------------------ + + procedure Check_Within_Time_Bounds (T : Time_Rep) is + begin + if Leap_Support then + if T < Ada_Low or else T > Ada_High_And_Leaps then + raise Time_Error; + end if; + else + if T < Ada_Low or else T > Ada_High then + raise Time_Error; + end if; + end if; + end Check_Within_Time_Bounds; + + ----------- + -- Clock -- + ----------- + + function Clock return Time is + Elapsed_Leaps : Natural; + Next_Leap_N : Time_Rep; + + -- The system clock returns the time in UTC since the Unix Epoch of + -- 1970-01-01 00:00:00.0. We perform an origin shift to the Ada Epoch + -- by adding the number of nanoseconds between the two origins. + + Res_N : Time_Rep := + Duration_To_Time_Rep (System.OS_Primitives.Clock) + + Unix_Min; + + begin + -- If the target supports leap seconds, determine the number of leap + -- seconds elapsed until this moment. + + if Leap_Support then + Cumulative_Leap_Seconds + (Start_Of_Time, Res_N, Elapsed_Leaps, Next_Leap_N); + + -- The system clock may fall exactly on a leap second + + if Res_N >= Next_Leap_N then + Elapsed_Leaps := Elapsed_Leaps + 1; + end if; + + -- The target does not support leap seconds + + else + Elapsed_Leaps := 0; + end if; + + Res_N := Res_N + Time_Rep (Elapsed_Leaps) * Nano; + + return Time (Res_N); + end Clock; + + ----------------------------- + -- Cumulative_Leap_Seconds -- + ----------------------------- + + procedure Cumulative_Leap_Seconds + (Start_Date : Time_Rep; + End_Date : Time_Rep; + Elapsed_Leaps : out Natural; + Next_Leap : out Time_Rep) + is + End_Index : Positive; + End_T : Time_Rep := End_Date; + Start_Index : Positive; + Start_T : Time_Rep := Start_Date; + + begin + -- Both input dates must be normalized to UTC + + pragma Assert (Leap_Support and then End_Date >= Start_Date); + + Next_Leap := End_Of_Time; + + -- Make sure that the end date does not exceed the upper bound + -- of Ada time. + + if End_Date > Ada_High then + End_T := Ada_High; + end if; + + -- Remove the sub seconds from both dates + + Start_T := Start_T - (Start_T mod Nano); + End_T := End_T - (End_T mod Nano); + + -- Some trivial cases: + -- Leap 1 . . . Leap N + -- ---+========+------+############+-------+========+----- + -- Start_T End_T Start_T End_T + + if End_T < Leap_Second_Times (1) then + Elapsed_Leaps := 0; + Next_Leap := Leap_Second_Times (1); + return; + + elsif Start_T > Leap_Second_Times (Leap_Seconds_Count) then + Elapsed_Leaps := 0; + Next_Leap := End_Of_Time; + return; + end if; + + -- Perform the calculations only if the start date is within the leap + -- second occurrences table. + + if Start_T <= Leap_Second_Times (Leap_Seconds_Count) then + + -- 1 2 N - 1 N + -- +----+----+-- . . . --+-------+---+ + -- | T1 | T2 | | N - 1 | N | + -- +----+----+-- . . . --+-------+---+ + -- ^ ^ + -- | Start_Index | End_Index + -- +-------------------+ + -- Leaps_Between + + -- The idea behind the algorithm is to iterate and find two + -- closest dates which are after Start_T and End_T. Their + -- corresponding index difference denotes the number of leap + -- seconds elapsed. + + Start_Index := 1; + loop + exit when Leap_Second_Times (Start_Index) >= Start_T; + Start_Index := Start_Index + 1; + end loop; + + End_Index := Start_Index; + loop + exit when End_Index > Leap_Seconds_Count + or else Leap_Second_Times (End_Index) >= End_T; + End_Index := End_Index + 1; + end loop; + + if End_Index <= Leap_Seconds_Count then + Next_Leap := Leap_Second_Times (End_Index); + end if; + + Elapsed_Leaps := End_Index - Start_Index; + + else + Elapsed_Leaps := 0; + end if; + end Cumulative_Leap_Seconds; + + --------- + -- Day -- + --------- + + function Day (Date : Time) return Day_Number is + D : Day_Number; + Y : Year_Number; + M : Month_Number; + S : Day_Duration; + pragma Unreferenced (Y, M, S); + begin + Split (Date, Y, M, D, S); + return D; + end Day; + + ------------- + -- Is_Leap -- + ------------- + + function Is_Leap (Year : Year_Number) return Boolean is + begin + -- Leap centennial years + + if Year mod 400 = 0 then + return True; + + -- Non-leap centennial years + + elsif Year mod 100 = 0 then + return False; + + -- Regular years + + else + return Year mod 4 = 0; + end if; + end Is_Leap; + + ----------- + -- Month -- + ----------- + + function Month (Date : Time) return Month_Number is + Y : Year_Number; + M : Month_Number; + D : Day_Number; + S : Day_Duration; + pragma Unreferenced (Y, D, S); + begin + Split (Date, Y, M, D, S); + return M; + end Month; + + ------------- + -- Seconds -- + ------------- + + function Seconds (Date : Time) return Day_Duration is + Y : Year_Number; + M : Month_Number; + D : Day_Number; + S : Day_Duration; + pragma Unreferenced (Y, M, D); + begin + Split (Date, Y, M, D, S); + return S; + end Seconds; + + ----------- + -- Split -- + ----------- + + procedure Split + (Date : Time; + Year : out Year_Number; + Month : out Month_Number; + Day : out Day_Number; + Seconds : out Day_Duration) + is + H : Integer; + M : Integer; + Se : Integer; + Ss : Duration; + Le : Boolean; + + pragma Unreferenced (H, M, Se, Ss, Le); + + begin + -- Even though the input time zone is UTC (0), the flag Is_Ada_05 will + -- ensure that Split picks up the local time zone. + + Formatting_Operations.Split + (Date => Date, + Year => Year, + Month => Month, + Day => Day, + Day_Secs => Seconds, + Hour => H, + Minute => M, + Second => Se, + Sub_Sec => Ss, + Leap_Sec => Le, + Is_Ada_05 => False, + Time_Zone => 0); + + -- Validity checks + + if not Year'Valid + or else not Month'Valid + or else not Day'Valid + or else not Seconds'Valid + then + raise Time_Error; + end if; + end Split; + + ------------- + -- Time_Of -- + ------------- + + function Time_Of + (Year : Year_Number; + Month : Month_Number; + Day : Day_Number; + Seconds : Day_Duration := 0.0) return Time + is + -- The values in the following constants are irrelevant, they are just + -- placeholders; the choice of constructing a Day_Duration value is + -- controlled by the Use_Day_Secs flag. + + H : constant Integer := 1; + M : constant Integer := 1; + Se : constant Integer := 1; + Ss : constant Duration := 0.1; + + begin + -- Validity checks + + if not Year'Valid + or else not Month'Valid + or else not Day'Valid + or else not Seconds'Valid + then + raise Time_Error; + end if; + + -- Even though the input time zone is UTC (0), the flag Is_Ada_05 will + -- ensure that Split picks up the local time zone. + + return + Formatting_Operations.Time_Of + (Year => Year, + Month => Month, + Day => Day, + Day_Secs => Seconds, + Hour => H, + Minute => M, + Second => Se, + Sub_Sec => Ss, + Leap_Sec => False, + Use_Day_Secs => True, + Is_Ada_05 => False, + Time_Zone => 0); + end Time_Of; + + ---------- + -- Year -- + ---------- + + function Year (Date : Time) return Year_Number is + Y : Year_Number; + M : Month_Number; + D : Day_Number; + S : Day_Duration; + pragma Unreferenced (M, D, S); + begin + Split (Date, Y, M, D, S); + return Y; + end Year; + + -- The following packages assume that Time is a signed 64 bit integer + -- type, the units are nanoseconds and the origin is the start of Ada + -- time (1901-01-01 00:00:00.0 UTC). + + --------------------------- + -- Arithmetic_Operations -- + --------------------------- + + package body Arithmetic_Operations is + + --------- + -- Add -- + --------- + + function Add (Date : Time; Days : Long_Integer) return Time is + pragma Unsuppress (Overflow_Check); + Date_N : constant Time_Rep := Time_Rep (Date); + begin + return Time (Date_N + Time_Rep (Days) * Nanos_In_Day); + exception + when Constraint_Error => + raise Time_Error; + end Add; + + ---------------- + -- Difference -- + ---------------- + + procedure Difference + (Left : Time; + Right : Time; + Days : out Long_Integer; + Seconds : out Duration; + Leap_Seconds : out Integer) + is + Res_Dur : Time_Dur; + Earlier : Time_Rep; + Elapsed_Leaps : Natural; + Later : Time_Rep; + Negate : Boolean := False; + Next_Leap_N : Time_Rep; + Sub_Secs : Duration; + Sub_Secs_Diff : Time_Rep; + + begin + -- Both input time values are assumed to be in UTC + + if Left >= Right then + Later := Time_Rep (Left); + Earlier := Time_Rep (Right); + else + Later := Time_Rep (Right); + Earlier := Time_Rep (Left); + Negate := True; + end if; + + -- If the target supports leap seconds, process them + + if Leap_Support then + Cumulative_Leap_Seconds + (Earlier, Later, Elapsed_Leaps, Next_Leap_N); + + if Later >= Next_Leap_N then + Elapsed_Leaps := Elapsed_Leaps + 1; + end if; + + -- The target does not support leap seconds + + else + Elapsed_Leaps := 0; + end if; + + -- Sub seconds processing. We add the resulting difference to one + -- of the input dates in order to account for any potential rounding + -- of the difference in the next step. + + Sub_Secs_Diff := Later mod Nano - Earlier mod Nano; + Earlier := Earlier + Sub_Secs_Diff; + Sub_Secs := Duration (Sub_Secs_Diff) / Nano_F; + + -- Difference processing. This operation should be able to calculate + -- the difference between opposite values which are close to the end + -- and start of Ada time. To accommodate the large range, we convert + -- to seconds. This action may potentially round the two values and + -- either add or drop a second. We compensate for this issue in the + -- previous step. + + Res_Dur := + Time_Dur (Later / Nano - Earlier / Nano) - Time_Dur (Elapsed_Leaps); + + Days := Long_Integer (Res_Dur / Secs_In_Day); + Seconds := Duration (Res_Dur mod Secs_In_Day) + Sub_Secs; + Leap_Seconds := Integer (Elapsed_Leaps); + + if Negate then + Days := -Days; + Seconds := -Seconds; + + if Leap_Seconds /= 0 then + Leap_Seconds := -Leap_Seconds; + end if; + end if; + end Difference; + + -------------- + -- Subtract -- + -------------- + + function Subtract (Date : Time; Days : Long_Integer) return Time is + pragma Unsuppress (Overflow_Check); + Date_N : constant Time_Rep := Time_Rep (Date); + begin + return Time (Date_N - Time_Rep (Days) * Nanos_In_Day); + exception + when Constraint_Error => + raise Time_Error; + end Subtract; + + end Arithmetic_Operations; + + --------------------------- + -- Conversion_Operations -- + --------------------------- + + package body Conversion_Operations is + + ----------------- + -- To_Ada_Time -- + ----------------- + + function To_Ada_Time (Unix_Time : Long_Integer) return Time is + pragma Unsuppress (Overflow_Check); + Unix_Rep : constant Time_Rep := Time_Rep (Unix_Time) * Nano; + begin + return Time (Unix_Rep - Epoch_Offset); + exception + when Constraint_Error => + raise Time_Error; + end To_Ada_Time; + + ----------------- + -- To_Ada_Time -- + ----------------- + + function To_Ada_Time + (tm_year : Integer; + tm_mon : Integer; + tm_day : Integer; + tm_hour : Integer; + tm_min : Integer; + tm_sec : Integer; + tm_isdst : Integer) return Time + is + pragma Unsuppress (Overflow_Check); + Year : Year_Number; + Month : Month_Number; + Day : Day_Number; + Second : Integer; + Leap : Boolean; + Result : Time_Rep; + + begin + -- Input processing + + Year := Year_Number (1900 + tm_year); + Month := Month_Number (1 + tm_mon); + Day := Day_Number (tm_day); + + -- Step 1: Validity checks of input values + + if not Year'Valid + or else not Month'Valid + or else not Day'Valid + or else tm_hour not in 0 .. 24 + or else tm_min not in 0 .. 59 + or else tm_sec not in 0 .. 60 + or else tm_isdst not in -1 .. 1 + then + raise Time_Error; + end if; + + -- Step 2: Potential leap second + + if tm_sec = 60 then + Leap := True; + Second := 59; + else + Leap := False; + Second := tm_sec; + end if; + + -- Step 3: Calculate the time value + + Result := + Time_Rep + (Formatting_Operations.Time_Of + (Year => Year, + Month => Month, + Day => Day, + Day_Secs => 0.0, -- Time is given in h:m:s + Hour => tm_hour, + Minute => tm_min, + Second => Second, + Sub_Sec => 0.0, -- No precise sub second given + Leap_Sec => Leap, + Use_Day_Secs => False, -- Time is given in h:m:s + Is_Ada_05 => True, -- Force usage of explicit time zone + Time_Zone => 0)); -- Place the value in UTC + + -- Step 4: Daylight Savings Time + + if tm_isdst = 1 then + Result := Result + Time_Rep (3_600) * Nano; + end if; + + return Time (Result); + + exception + when Constraint_Error => + raise Time_Error; + end To_Ada_Time; + + ----------------- + -- To_Duration -- + ----------------- + + function To_Duration + (tv_sec : Long_Integer; + tv_nsec : Long_Integer) return Duration + is + pragma Unsuppress (Overflow_Check); + begin + return Duration (tv_sec) + Duration (tv_nsec) / Nano_F; + end To_Duration; + + ------------------------ + -- To_Struct_Timespec -- + ------------------------ + + procedure To_Struct_Timespec + (D : Duration; + tv_sec : out Long_Integer; + tv_nsec : out Long_Integer) + is + pragma Unsuppress (Overflow_Check); + Secs : Duration; + Nano_Secs : Duration; + + begin + -- Seconds extraction, avoid potential rounding errors + + Secs := D - 0.5; + tv_sec := Long_Integer (Secs); + + -- Nanoseconds extraction + + Nano_Secs := D - Duration (tv_sec); + tv_nsec := Long_Integer (Nano_Secs * Nano); + end To_Struct_Timespec; + + ------------------ + -- To_Struct_Tm -- + ------------------ + + procedure To_Struct_Tm + (T : Time; + tm_year : out Integer; + tm_mon : out Integer; + tm_day : out Integer; + tm_hour : out Integer; + tm_min : out Integer; + tm_sec : out Integer) + is + pragma Unsuppress (Overflow_Check); + Year : Year_Number; + Month : Month_Number; + Second : Integer; + Day_Secs : Day_Duration; + Sub_Sec : Duration; + Leap_Sec : Boolean; + + begin + -- Step 1: Split the input time + + Formatting_Operations.Split + (T, Year, Month, tm_day, Day_Secs, + tm_hour, tm_min, Second, Sub_Sec, Leap_Sec, True, 0); + + -- Step 2: Correct the year and month + + tm_year := Year - 1900; + tm_mon := Month - 1; + + -- Step 3: Handle leap second occurrences + + tm_sec := (if Leap_Sec then 60 else Second); + end To_Struct_Tm; + + ------------------ + -- To_Unix_Time -- + ------------------ + + function To_Unix_Time (Ada_Time : Time) return Long_Integer is + pragma Unsuppress (Overflow_Check); + Ada_Rep : constant Time_Rep := Time_Rep (Ada_Time); + begin + return Long_Integer ((Ada_Rep + Epoch_Offset) / Nano); + exception + when Constraint_Error => + raise Time_Error; + end To_Unix_Time; + end Conversion_Operations; + + ---------------------- + -- Delay_Operations -- + ---------------------- + + package body Delay_Operations is + + ----------------- + -- To_Duration -- + ----------------- + + function To_Duration (Date : Time) return Duration is + pragma Unsuppress (Overflow_Check); + + Safe_Ada_High : constant Time_Rep := Ada_High - Epoch_Offset; + -- This value represents a "safe" end of time. In order to perform a + -- proper conversion to Unix duration, we will have to shift origins + -- at one point. For very distant dates, this means an overflow check + -- failure. To prevent this, the function returns the "safe" end of + -- time (roughly 2219) which is still distant enough. + + Elapsed_Leaps : Natural; + Next_Leap_N : Time_Rep; + Res_N : Time_Rep; + + begin + Res_N := Time_Rep (Date); + + -- Step 1: If the target supports leap seconds, remove any leap + -- seconds elapsed up to the input date. + + if Leap_Support then + Cumulative_Leap_Seconds + (Start_Of_Time, Res_N, Elapsed_Leaps, Next_Leap_N); + + -- The input time value may fall on a leap second occurrence + + if Res_N >= Next_Leap_N then + Elapsed_Leaps := Elapsed_Leaps + 1; + end if; + + -- The target does not support leap seconds + + else + Elapsed_Leaps := 0; + end if; + + Res_N := Res_N - Time_Rep (Elapsed_Leaps) * Nano; + + -- Step 2: Perform a shift in origins to obtain a Unix equivalent of + -- the input. Guard against very large delay values such as the end + -- of time since the computation will overflow. + + Res_N := (if Res_N > Safe_Ada_High then Safe_Ada_High + else Res_N + Epoch_Offset); + + return Time_Rep_To_Duration (Res_N); + end To_Duration; + + end Delay_Operations; + + --------------------------- + -- Formatting_Operations -- + --------------------------- + + package body Formatting_Operations is + + ----------------- + -- Day_Of_Week -- + ----------------- + + function Day_Of_Week (Date : Time) return Integer is + Date_N : constant Time_Rep := Time_Rep (Date); + Time_Zone : constant Long_Integer := + Time_Zones_Operations.UTC_Time_Offset (Date); + + Ada_Low_N : Time_Rep; + Day_Count : Long_Integer; + Day_Dur : Time_Dur; + High_N : Time_Rep; + Low_N : Time_Rep; + + begin + -- As declared, the Ada Epoch is set in UTC. For this calculation to + -- work properly, both the Epoch and the input date must be in the + -- same time zone. The following places the Epoch in the input date's + -- time zone. + + Ada_Low_N := Ada_Low - Time_Rep (Time_Zone) * Nano; + + if Date_N > Ada_Low_N then + High_N := Date_N; + Low_N := Ada_Low_N; + else + High_N := Ada_Low_N; + Low_N := Date_N; + end if; + + -- Determine the elapsed seconds since the start of Ada time + + Day_Dur := Time_Dur (High_N / Nano - Low_N / Nano); + + -- Count the number of days since the start of Ada time. 1901-01-01 + -- GMT was a Tuesday. + + Day_Count := Long_Integer (Day_Dur / Secs_In_Day) + 1; + + return Integer (Day_Count mod 7); + end Day_Of_Week; + + ----------- + -- Split -- + ----------- + + 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) + is + -- The following constants represent the number of nanoseconds + -- elapsed since the start of Ada time to and including the non + -- leap centennial years. + + Year_2101 : constant Time_Rep := Ada_Low + + Time_Rep (49 * 366 + 151 * 365) * Nanos_In_Day; + Year_2201 : constant Time_Rep := Ada_Low + + Time_Rep (73 * 366 + 227 * 365) * Nanos_In_Day; + Year_2301 : constant Time_Rep := Ada_Low + + Time_Rep (97 * 366 + 303 * 365) * Nanos_In_Day; + + Date_Dur : Time_Dur; + Date_N : Time_Rep; + Day_Seconds : Natural; + Elapsed_Leaps : Natural; + Four_Year_Segs : Natural; + Hour_Seconds : Natural; + Is_Leap_Year : Boolean; + Next_Leap_N : Time_Rep; + Rem_Years : Natural; + Sub_Sec_N : Time_Rep; + Year_Day : Natural; + + begin + Date_N := Time_Rep (Date); + + -- Step 1: Leap seconds processing in UTC + + if Leap_Support then + Cumulative_Leap_Seconds + (Start_Of_Time, Date_N, Elapsed_Leaps, Next_Leap_N); + + Leap_Sec := Date_N >= Next_Leap_N; + + if Leap_Sec then + Elapsed_Leaps := Elapsed_Leaps + 1; + end if; + + -- The target does not support leap seconds + + else + Elapsed_Leaps := 0; + Leap_Sec := False; + end if; + + Date_N := Date_N - Time_Rep (Elapsed_Leaps) * Nano; + + -- Step 2: Time zone processing. This action converts the input date + -- from GMT to the requested time zone. + + if Is_Ada_05 then + if Time_Zone /= 0 then + Date_N := Date_N + Time_Rep (Time_Zone) * 60 * Nano; + end if; + + -- Ada 83 and 95 + + else + declare + Off : constant Long_Integer := + Time_Zones_Operations.UTC_Time_Offset (Time (Date_N)); + begin + Date_N := Date_N + Time_Rep (Off) * Nano; + end; + end if; + + -- Step 3: Non-leap centennial year adjustment in local time zone + + -- In order for all divisions to work properly and to avoid more + -- complicated arithmetic, we add fake February 29s to dates which + -- occur after a non-leap centennial year. + + if Date_N >= Year_2301 then + Date_N := Date_N + Time_Rep (3) * Nanos_In_Day; + + elsif Date_N >= Year_2201 then + Date_N := Date_N + Time_Rep (2) * Nanos_In_Day; + + elsif Date_N >= Year_2101 then + Date_N := Date_N + Time_Rep (1) * Nanos_In_Day; + end if; + + -- Step 4: Sub second processing in local time zone + + Sub_Sec_N := Date_N mod Nano; + Sub_Sec := Duration (Sub_Sec_N) / Nano_F; + Date_N := Date_N - Sub_Sec_N; + + -- Convert Date_N into a time duration value, changing the units + -- to seconds. + + Date_Dur := Time_Dur (Date_N / Nano - Ada_Low / Nano); + + -- Step 5: Year processing in local time zone. Determine the number + -- of four year segments since the start of Ada time and the input + -- date. + + Four_Year_Segs := Natural (Date_Dur / Secs_In_Four_Years); + + if Four_Year_Segs > 0 then + Date_Dur := Date_Dur - Time_Dur (Four_Year_Segs) * + Secs_In_Four_Years; + end if; + + -- Calculate the remaining non-leap years + + Rem_Years := Natural (Date_Dur / Secs_In_Non_Leap_Year); + + if Rem_Years > 3 then + Rem_Years := 3; + end if; + + Date_Dur := Date_Dur - Time_Dur (Rem_Years) * Secs_In_Non_Leap_Year; + + Year := Ada_Min_Year + Natural (4 * Four_Year_Segs + Rem_Years); + Is_Leap_Year := Is_Leap (Year); + + -- Step 6: Month and day processing in local time zone + + Year_Day := Natural (Date_Dur / Secs_In_Day) + 1; + + Month := 1; + + -- Processing for months after January + + if Year_Day > 31 then + Month := 2; + Year_Day := Year_Day - 31; + + -- Processing for a new month or a leap February + + if Year_Day > 28 + and then (not Is_Leap_Year or else Year_Day > 29) + then + Month := 3; + Year_Day := Year_Day - 28; + + if Is_Leap_Year then + Year_Day := Year_Day - 1; + end if; + + -- Remaining months + + while Year_Day > Days_In_Month (Month) loop + Year_Day := Year_Day - Days_In_Month (Month); + Month := Month + 1; + end loop; + end if; + end if; + + -- Step 7: Hour, minute, second and sub second processing in local + -- time zone. + + Day := Day_Number (Year_Day); + Day_Seconds := Integer (Date_Dur mod Secs_In_Day); + Day_Secs := Duration (Day_Seconds) + Sub_Sec; + Hour := Day_Seconds / 3_600; + Hour_Seconds := Day_Seconds mod 3_600; + Minute := Hour_Seconds / 60; + Second := Hour_Seconds mod 60; + end Split; + + ------------- + -- Time_Of -- + ------------- + + 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 := False; + Use_Day_Secs : Boolean := False; + Is_Ada_05 : Boolean := False; + Time_Zone : Long_Integer := 0) return Time + is + Count : Integer; + Elapsed_Leaps : Natural; + Next_Leap_N : Time_Rep; + Res_N : Time_Rep; + Rounded_Res_N : Time_Rep; + + begin + -- Step 1: Check whether the day, month and year form a valid date + + if Day > Days_In_Month (Month) + and then (Day /= 29 or else Month /= 2 or else not Is_Leap (Year)) + then + raise Time_Error; + end if; + + -- Start accumulating nanoseconds from the low bound of Ada time + + Res_N := Ada_Low; + + -- Step 2: Year processing and centennial year adjustment. Determine + -- the number of four year segments since the start of Ada time and + -- the input date. + + Count := (Year - Year_Number'First) / 4; + for Four_Year_Segments in 1 .. Count loop + Res_N := Res_N + Nanos_In_Four_Years; + end loop; + + -- Note that non-leap centennial years are automatically considered + -- leap in the operation above. An adjustment of several days is + -- required to compensate for this. + + if Year > 2300 then + Res_N := Res_N - Time_Rep (3) * Nanos_In_Day; + + elsif Year > 2200 then + Res_N := Res_N - Time_Rep (2) * Nanos_In_Day; + + elsif Year > 2100 then + Res_N := Res_N - Time_Rep (1) * Nanos_In_Day; + end if; + + -- Add the remaining non-leap years + + Count := (Year - Year_Number'First) mod 4; + Res_N := Res_N + Time_Rep (Count) * Secs_In_Non_Leap_Year * Nano; + + -- Step 3: Day of month processing. Determine the number of days + -- since the start of the current year. Do not add the current + -- day since it has not elapsed yet. + + Count := Cumulative_Days_Before_Month (Month) + Day - 1; + + -- The input year is leap and we have passed February + + if Is_Leap (Year) + and then Month > 2 + then + Count := Count + 1; + end if; + + Res_N := Res_N + Time_Rep (Count) * Nanos_In_Day; + + -- Step 4: Hour, minute, second and sub second processing + + if Use_Day_Secs then + Res_N := Res_N + Duration_To_Time_Rep (Day_Secs); + + else + Res_N := + Res_N + Time_Rep (Hour * 3_600 + Minute * 60 + Second) * Nano; + + if Sub_Sec = 1.0 then + Res_N := Res_N + Time_Rep (1) * Nano; + else + Res_N := Res_N + Duration_To_Time_Rep (Sub_Sec); + end if; + end if; + + -- At this point, the generated time value should be withing the + -- bounds of Ada time. + + Check_Within_Time_Bounds (Res_N); + + -- Step 4: Time zone processing. At this point we have built an + -- arbitrary time value which is not related to any time zone. + -- For simplicity, the time value is normalized to GMT, producing + -- a uniform representation which can be treated by arithmetic + -- operations for instance without any additional corrections. + + if Is_Ada_05 then + if Time_Zone /= 0 then + Res_N := Res_N - Time_Rep (Time_Zone) * 60 * Nano; + end if; + + -- Ada 83 and 95 + + else + declare + Current_Off : constant Long_Integer := + Time_Zones_Operations.UTC_Time_Offset + (Time (Res_N)); + Current_Res_N : constant Time_Rep := + Res_N - Time_Rep (Current_Off) * Nano; + Off : constant Long_Integer := + Time_Zones_Operations.UTC_Time_Offset + (Time (Current_Res_N)); + begin + Res_N := Res_N - Time_Rep (Off) * Nano; + end; + end if; + + -- Step 5: Leap seconds processing in GMT + + if Leap_Support then + Cumulative_Leap_Seconds + (Start_Of_Time, Res_N, Elapsed_Leaps, Next_Leap_N); + + Res_N := Res_N + Time_Rep (Elapsed_Leaps) * Nano; + + -- An Ada 2005 caller requesting an explicit leap second or an + -- Ada 95 caller accounting for an invisible leap second. + + if Leap_Sec + or else Res_N >= Next_Leap_N + then + Res_N := Res_N + Time_Rep (1) * Nano; + end if; + + -- Leap second validity check + + Rounded_Res_N := Res_N - (Res_N mod Nano); + + if Is_Ada_05 + and then Leap_Sec + and then Rounded_Res_N /= Next_Leap_N + then + raise Time_Error; + end if; + end if; + + return Time (Res_N); + end Time_Of; + + end Formatting_Operations; + + --------------------------- + -- Time_Zones_Operations -- + --------------------------- + + package body Time_Zones_Operations is + + -- The Unix time bounds in nanoseconds: 1970/1/1 .. 2037/1/1 + + Unix_Min : constant Time_Rep := Ada_Low + + Time_Rep (17 * 366 + 52 * 365) * Nanos_In_Day; + + Unix_Max : constant Time_Rep := Ada_Low + + Time_Rep (34 * 366 + 102 * 365) * Nanos_In_Day + + Time_Rep (Leap_Seconds_Count) * Nano; + + -- The following constants denote February 28 during non-leap + -- centennial years, the units are nanoseconds. + + T_2100_2_28 : constant Time_Rep := Ada_Low + + (Time_Rep (49 * 366 + 150 * 365 + 59) * Secs_In_Day + + Time_Rep (Leap_Seconds_Count)) * Nano; + + T_2200_2_28 : constant Time_Rep := Ada_Low + + (Time_Rep (73 * 366 + 226 * 365 + 59) * Secs_In_Day + + Time_Rep (Leap_Seconds_Count)) * Nano; + + T_2300_2_28 : constant Time_Rep := Ada_Low + + (Time_Rep (97 * 366 + 302 * 365 + 59) * Secs_In_Day + + Time_Rep (Leap_Seconds_Count)) * Nano; + + -- 56 years (14 leap years + 42 non leap years) in nanoseconds: + + Nanos_In_56_Years : constant := (14 * 366 + 42 * 365) * Nanos_In_Day; + + subtype long is Long_Integer; + type long_Pointer is access all long; + + type time_t is + range -(2 ** (Standard'Address_Size - Integer'(1))) .. + +(2 ** (Standard'Address_Size - Integer'(1)) - 1); + type time_t_Pointer is access all time_t; + + procedure localtime_tzoff + (timer : time_t_Pointer; + off : long_Pointer); + pragma Import (C, localtime_tzoff, "__gnat_localtime_tzoff"); + -- This is a lightweight wrapper around the system library function + -- localtime_r. Parameter 'off' captures the UTC offset which is either + -- retrieved from the tm struct or calculated from the 'timezone' extern + -- and the tm_isdst flag in the tm struct. + + --------------------- + -- UTC_Time_Offset -- + --------------------- + + function UTC_Time_Offset (Date : Time) return Long_Integer is + Adj_Cent : Integer; + Date_N : Time_Rep; + Offset : aliased long; + Secs_T : aliased time_t; + + begin + Date_N := Time_Rep (Date); + + -- Dates which are 56 years apart fall on the same day, day light + -- saving and so on. Non-leap centennial years violate this rule by + -- one day and as a consequence, special adjustment is needed. + + Adj_Cent := + (if Date_N <= T_2100_2_28 then 0 + elsif Date_N <= T_2200_2_28 then 1 + elsif Date_N <= T_2300_2_28 then 2 + else 3); + + if Adj_Cent > 0 then + Date_N := Date_N - Time_Rep (Adj_Cent) * Nanos_In_Day; + end if; + + -- Shift the date within bounds of Unix time + + while Date_N < Unix_Min loop + Date_N := Date_N + Nanos_In_56_Years; + end loop; + + while Date_N >= Unix_Max loop + Date_N := Date_N - Nanos_In_56_Years; + end loop; + + -- Perform a shift in origins from Ada to Unix + + Date_N := Date_N - Unix_Min; + + -- Convert the date into seconds + + Secs_T := time_t (Date_N / Nano); + + localtime_tzoff + (Secs_T'Unchecked_Access, + Offset'Unchecked_Access); + + return Offset; + end UTC_Time_Offset; + + end Time_Zones_Operations; + +-- Start of elaboration code for Ada.Calendar + +begin + System.OS_Primitives.Initialize; +end Ada.Calendar; -- cgit v1.2.3