-- --
-- B o d y --
-- --
--- Copyright (C) 1992-2008, Free Software Foundation, Inc. --
+-- 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 2, or (at your option) any later ver- --
+-- 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. 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. --
+-- or FITNESS FOR A PARTICULAR PURPOSE. --
-- --
--- 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. --
+-- 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. --
-- The above flag controls the usage of leap seconds in all Ada.Calendar
-- routines.
- Leap_Seconds_Count : constant Natural := 23;
+ 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
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);
-4859827181000000000,
-4812566380000000000,
-4765132779000000000,
- -4544207978000000000);
+ -4544207978000000000,
+ -4449513577000000000);
---------
-- "+" --
package body Conversion_Operations is
- 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.
-
-----------------
-- To_Ada_Time --
-----------------
-- Step 3: Handle leap second occurrences
- if Leap_Sec then
- tm_sec := 60;
- else
- tm_sec := Second;
- end if;
+ tm_sec := (if Leap_Sec then 60 else Second);
end To_Struct_Tm;
------------------
-----------------
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);
- -- If the target supports leap seconds, remove any leap seconds
- -- elapsed up to the input 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
Res_N := Res_N - Time_Rep (Elapsed_Leaps) * Nano;
- -- Perform a shift in origins, note that enforcing type Time on
- -- both operands will invoke Ada.Calendar."-".
+ -- 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 (Res_N) - Time (Unix_Min);
+ return Time_Rep_To_Duration (Res_N);
end To_Duration;
end Delay_Operations;
-----------------
function Day_Of_Week (Date : Time) return Integer is
- Y : Year_Number;
- Mo : Month_Number;
- D : Day_Number;
- Ds : Day_Duration;
- H : Integer;
- Mi : Integer;
- Se : Integer;
- Su : Duration;
- Le : Boolean;
-
- pragma Unreferenced (Ds, H, Mi, Se, Su, Le);
+ 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;
- Res_Dur : Time_Dur;
- Res_N : Time_Rep;
+ Day_Dur : Time_Dur;
+ High_N : Time_Rep;
+ Low_N : Time_Rep;
begin
- Formatting_Operations.Split
- (Date => Date,
- Year => Y,
- Month => Mo,
- Day => D,
- Day_Secs => Ds,
- Hour => H,
- Minute => Mi,
- Second => Se,
- Sub_Sec => Su,
- Leap_Sec => Le,
- Is_Ada_05 => True,
- Time_Zone => 0);
-
- -- Build a time value in the middle of the same day
-
- Res_N :=
- Time_Rep
- (Formatting_Operations.Time_Of
- (Year => Y,
- Month => Mo,
- Day => D,
- Day_Secs => 0.0,
- Hour => 12,
- Minute => 0,
- Second => 0,
- Sub_Sec => 0.0,
- Leap_Sec => False,
- Use_Day_Secs => False,
- Is_Ada_05 => True,
- Time_Zone => 0));
+ -- 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
- Res_Dur := Time_Dur (Res_N / Nano - Ada_Low / Nano);
+ Day_Dur := Time_Dur (High_N / Nano - Low_N / Nano);
- -- Count the number of days since the start of Ada time. 1901-1-1
+ -- Count the number of days since the start of Ada time. 1901-01-01
-- GMT was a Tuesday.
- Day_Count := Long_Integer (Res_Dur / Secs_In_Day) + 1;
+ Day_Count := Long_Integer (Day_Dur / Secs_In_Day) + 1;
return Integer (Day_Count mod 7);
end Day_Of_Week;
-- the input date.
Count := (Year - Year_Number'First) / 4;
- Res_N := Res_N + Time_Rep (Count) * Secs_In_Four_Years * Nano;
+ 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
Res_N := Res_N + Duration_To_Time_Rep (Day_Secs);
else
- Res_N := Res_N +
- Time_Rep (Hour * 3_600 + Minute * 60 + Second) * Nano;
+ 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;
Nanos_In_56_Years : constant := (14 * 366 + 42 * 365) * Nanos_In_Day;
- -- Base C types. There is no point dragging in Interfaces.C just for
- -- these four types.
-
- type char_Pointer is access Character;
- subtype int is Integer;
subtype long is Long_Integer;
type long_Pointer is access all long;
- -- The Ada equivalent of struct tm and type time_t
-
- type tm is record
- tm_sec : int; -- seconds after the minute (0 .. 60)
- tm_min : int; -- minutes after the hour (0 .. 59)
- tm_hour : int; -- hours since midnight (0 .. 24)
- tm_mday : int; -- day of the month (1 .. 31)
- tm_mon : int; -- months since January (0 .. 11)
- tm_year : int; -- years since 1900
- tm_wday : int; -- days since Sunday (0 .. 6)
- tm_yday : int; -- days since January 1 (0 .. 365)
- tm_isdst : int; -- Daylight Savings Time flag (-1 .. 1)
- tm_gmtoff : long; -- offset from UTC in seconds
- tm_zone : char_Pointer; -- timezone abbreviation
- end record;
-
- type tm_Pointer is access all tm;
-
- subtype time_t is 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
- (C : time_t_Pointer;
- res : tm_Pointer;
- off : long_Pointer);
+ (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
---------------------
function UTC_Time_Offset (Date : Time) return Long_Integer is
- Adj_Cent : Integer := 0;
+ Adj_Cent : Integer;
Date_N : Time_Rep;
Offset : aliased long;
Secs_T : aliased time_t;
- Secs_TM : aliased tm;
begin
Date_N := Time_Rep (Date);
-- saving and so on. Non-leap centennial years violate this rule by
-- one day and as a consequence, special adjustment is needed.
- if Date_N > T_2100_2_28 then
- if Date_N > T_2200_2_28 then
- if Date_N > T_2300_2_28 then
- Adj_Cent := 3;
- else
- Adj_Cent := 2;
- end if;
-
- else
- Adj_Cent := 1;
- end if;
- end if;
+ 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;
localtime_tzoff
(Secs_T'Unchecked_Access,
- Secs_TM'Unchecked_Access,
Offset'Unchecked_Access);
return Offset;
OSDN Git Service
