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diff --git a/gcc-4.7/gcc/ada/a-calend.ads b/gcc-4.7/gcc/ada/a-calend.ads new file mode 100644 index 000000000..60319c254 --- /dev/null +++ b/gcc-4.7/gcc/ada/a-calend.ads @@ -0,0 +1,394 @@ +------------------------------------------------------------------------------ +-- -- +-- GNAT RUN-TIME COMPONENTS -- +-- -- +-- A D A . C A L E N D A R -- +-- -- +-- S p e c -- +-- -- +-- Copyright (C) 1992-2012, 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 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. -- +-- -- +------------------------------------------------------------------------------ + +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 .. 2399; + subtype Month_Number is Integer range 1 .. 12; + subtype Day_Number is Integer range 1 .. 31; + + -- A Day_Duration value of 86_400.0 designates a new day + + subtype Day_Duration is Duration range 0.0 .. 86_400.0; + + function Clock return Time; + -- The returned time value is the number of nanoseconds since the start + -- of Ada time (1901-01-01 00:00:00.0 UTC). If leap seconds are enabled, + -- the result will contain all elapsed leap seconds since the start of + -- Ada time until now. + + 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); + -- Break down a time value into its date components set in the current + -- time zone. If Split is called on a time value created using Ada 2005 + -- Time_Of in some arbitrary time zone, the input value will always be + -- interpreted as relative to the local time zone. + + 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; + -- The first three functions will raise Time_Error if the resulting time + -- value is less than the start of Ada time in UTC or greater than the + -- end of Ada time in UTC. The last function will raise Time_Error if the + -- resulting difference cannot fit into a duration value. + + 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 (">="); + + -- The units used in this version of Ada.Calendar are nanoseconds. The + -- following constants provide values used in conversions of seconds or + -- days to the underlying units. + + Nano : constant := 1_000_000_000; + Nano_F : constant := 1_000_000_000.0; + Nanos_In_Day : constant := 86_400_000_000_000; + Secs_In_Day : constant := 86_400; + + ---------------------------- + -- Implementation of Time -- + ---------------------------- + + -- Time is represented as a signed 64 bit integer count of nanoseconds + -- since the start of Ada time (1901-01-01 00:00:00.0 UTC). Time values + -- produced by Time_Of are internally normalized to UTC regardless of their + -- local time zone. This representation ensures correct handling of leap + -- seconds as well as performing arithmetic. In Ada 95, Split and Time_Of + -- will treat a time value as being in the local time zone, in Ada 2005, + -- Split and Time_Of will treat a time value as being in the designated + -- time zone by the formal parameter or in UTC by default. The size of the + -- type is large enough to cover the Ada 2005 range of time (1901-01-01 + -- 00:00:00.0 UTC - 2399-12-31-23:59:59.999999999 UTC). + + ------------------ + -- Leap Seconds -- + ------------------ + + -- Due to Earth's slowdown, the astronomical time is not as precise as the + -- International Atomic Time. To compensate for this inaccuracy, a single + -- leap second is added after the last day of June or December. The count + -- of seconds during those occurrences becomes: + + -- ... 58, 59, leap second 60, 0, 1, 2 ... + + -- Unlike leap days, leap seconds occur simultaneously around the world. + -- In other words, if a leap second occurs at 23:59:60 UTC, it also occurs + -- on 18:59:60 -5 the same day or 2:59:60 +2 on the next day. + + -- Leap seconds do not follow a formula. The International Earth Rotation + -- and Reference System Service decides when to add one. Leap seconds are + -- included in the representation of time in Ada 95 mode. As a result, + -- the following two time values will differ by two seconds: + + -- 1972-06-30 23:59:59.0 + -- 1972-07-01 00:00:00.0 + + -- When a new leap second is introduced, the following steps must be + -- carried out: + + -- 1) Increment Leap_Seconds_Count in a-calend.adb by one + -- 2) Increment LS_Count in xleaps.adb by one + -- 3) Add the new date to the aggregate of array LS_Dates in + -- xleaps.adb + -- 4) Compile and execute xleaps + -- 5) Replace the values of Leap_Second_Times in a-calend.adb with the + -- aggregate generated by xleaps + + -- The algorithms that build the actual leap second values and discover + -- how many leap seconds have occurred between two dates do not need any + -- modification. + + ------------------------------ + -- Non-leap Centennial Years -- + ------------------------------ + + -- Over the range of Ada time, centennial years 2100, 2200 and 2300 are + -- non-leap. As a consequence, seven non-leap years occur over the period + -- of year - 4 to year + 4. Internally, routines Split and Time_Of add or + -- subtract a "fake" February 29 to facilitate the arithmetic involved. + + ------------------------------------ + -- Time Zones and UTC_Time_Offset -- + ------------------------------------ + + -- The implementation-defined time zone of Ada.Calendar routines is the + -- local time zone. The term "local time zone" can be interpreted in two + -- different ways - either the offset from UTC of the "now" or the offset + -- from UTC of some input date. + + -- For efficency reasons, Split and Time_Of take the first approach. Since + -- the Ada Reference Manual does not mandate that Split and Time_Of should + -- be concious of historic time zones, this interpretation is acceptable + -- and efficent in terms of performance. Split and Time_Of localize their + -- respective input regardless of whether it represent a past or a future + -- date. + + -- UTC_Time_Offset on the other hand must be knowledgeable of historic time + -- zones. To achieve this, the implementation relies on various operating + -- system routines. Note that not all operating systems support time zones. + -- UTC_Time_Offset calculates the offset from UTC as it occurred or will + -- occur on the input date relative to the local time zone. Example: + + -- Date Offset Reason + -- 2012-01-11 -300 + -- 2011-03-12 -300 + -- 2011-03-14 -240 Daylight savings is in effect + + ------------------------ + -- Local Declarations -- + ------------------------ + + type Time_Rep is range -2 ** 63 .. +2 ** 63 - 1; + type Time is new Time_Rep; + -- The underlying type of Time has been chosen to be a 64 bit signed + -- integer number since it allows for easier processing of sub seconds + -- and arithmetic. + + Days_In_Month : constant array (Month_Number) of Day_Number := + (31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31); + -- Days in month for non-leap year, leap year case is adjusted in code + + Invalid_Time_Zone_Offset : Long_Integer; + pragma Import (C, Invalid_Time_Zone_Offset, "__gnat_invalid_tzoff"); + + function Is_Leap (Year : Year_Number) return Boolean; + -- Determine whether a given year is leap + + ---------------------------------------------------------- + -- Target-Independent Interface to Children of Calendar -- + ---------------------------------------------------------- + + -- The following packages provide a target-independent interface to the + -- children of Calendar - Arithmetic, Conversions, Delays, Formatting and + -- Time_Zones. + + --------------------------- + -- Arithmetic_Operations -- + --------------------------- + + package Arithmetic_Operations is + + function Add (Date : Time; Days : Long_Integer) return Time; + -- Add a certain number of days to a time value + + procedure Difference + (Left : Time; + Right : Time; + Days : out Long_Integer; + Seconds : out Duration; + Leap_Seconds : out Integer); + -- Calculate the difference between two time values in terms of days, + -- seconds and leap seconds elapsed. The leap seconds are not included + -- in the seconds returned. If Left is greater than Right, the returned + -- values are positive, negative otherwise. + + function Subtract (Date : Time; Days : Long_Integer) return Time; + -- Subtract a certain number of days from a time value + + end Arithmetic_Operations; + + --------------------------- + -- Conversion_Operations -- + --------------------------- + + package Conversion_Operations is + + function To_Ada_Time (Unix_Time : Long_Integer) return Time; + -- Unix to Ada Epoch conversion + + 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; + -- Struct tm to Ada Epoch conversion + + function To_Duration + (tv_sec : Long_Integer; + tv_nsec : Long_Integer) return Duration; + -- Struct timespec to Duration conversion + + procedure To_Struct_Timespec + (D : Duration; + tv_sec : out Long_Integer; + tv_nsec : out Long_Integer); + -- Duration to struct timespec conversion + + 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); + -- Time to struct tm conversion + + function To_Unix_Time (Ada_Time : Time) return Long_Integer; + -- Ada to Unix Epoch conversion + + end Conversion_Operations; + + ---------------------- + -- Delay_Operations -- + ---------------------- + + package Delay_Operations is + + function To_Duration (Date : Time) return Duration; + -- Given a time value in nanoseconds since 1901, convert it into a + -- duration value giving the number of nanoseconds since the Unix Epoch. + + end Delay_Operations; + + --------------------------- + -- Formatting_Operations -- + --------------------------- + + package Formatting_Operations is + + function Day_Of_Week (Date : Time) return Integer; + -- Determine which day of week Date falls on. The returned values are + -- within the range of 0 .. 6 (Monday .. Sunday). + + 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); + -- Split a time value into its components. Set Is_Ada_05 to use the + -- local time zone (the value in Time_Zone is ignored) when splitting + -- a time value. + + 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; + -- Given all the components of a date, return the corresponding time + -- value. Set Use_Day_Secs to use the value in Day_Secs, otherwise the + -- day duration will be calculated from Hour, Minute, Second and Sub_ + -- Sec. Set Is_Ada_05 to use the local time zone (the value in formal + -- Time_Zone is ignored) when building a time value and to verify the + -- validity of a requested leap second. + + end Formatting_Operations; + + --------------------------- + -- Time_Zones_Operations -- + --------------------------- + + package Time_Zones_Operations is + + function UTC_Time_Offset (Date : Time) return Long_Integer; + -- Return (in seconds) the difference between the local time zone and + -- UTC time at a specific historic date. + + end Time_Zones_Operations; + +end Ada.Calendar; |