gcc/ada/a-calend-vms.ads

   1 ------------------------------------------------------------------------------
   2 --                                                                          --
   3 --                         GNAT RUN-TIME COMPONENTS                         --
   4 --                                                                          --
   5 --                         A D A . C A L E N D A R                          --
   6 --                                                                          --
   7 --                                 S p e c                                  --
   8 --                                                                          --
   9 --          Copyright (C) 1992-2009, Free Software Foundation, Inc.         --
  10 --                                                                          --
  11 -- This specification is derived from the Ada Reference Manual for use with --
  12 -- GNAT. The copyright notice above, and the license provisions that follow --
  13 -- apply solely to the  contents of the part following the private keyword. --
  14 --                                                                          --
  15 -- GNAT is free software;  you can  redistribute it  and/or modify it under --
  16 -- terms of the  GNU General Public License as published  by the Free Soft- --
  17 -- ware  Foundation;  either version 3,  or (at your option) any later ver- --
  18 -- sion.  GNAT is distributed in the hope that it will be useful, but WITH- --
  19 -- OUT ANY WARRANTY;  without even the  implied warranty of MERCHANTABILITY --
  20 -- or FITNESS FOR A PARTICULAR PURPOSE.                                     --
  21 --                                                                          --
  22 -- As a special exception under Section 7 of GPL version 3, you are granted --
  23 -- additional permissions described in the GCC Runtime Library Exception,   --
  24 -- version 3.1, as published by the Free Software Foundation.               --
  25 --                                                                          --
  26 -- You should have received a copy of the GNU General Public License and    --
  27 -- a copy of the GCC Runtime Library Exception along with this program;     --
  28 -- see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see    --
  29 -- <http://www.gnu.org/licenses/>.                                          --
  30 --                                                                          --
  31 -- GNAT was originally developed  by the GNAT team at  New York University. --
  32 -- Extensive contributions were provided by Ada Core Technologies Inc.      --
  33 --                                                                          --
  34 ------------------------------------------------------------------------------
  35
  36 --  This is the Alpha/VMS version
  37
  38 with System.OS_Primitives;
  39
  40 package Ada.Calendar is
  41
  42    package OSP renames System.OS_Primitives;
  43
  44    type Time is private;
  45
  46    --  Declarations representing limits of allowed local time values. Note
  47    --  that these do NOT constrain the possible stored values of time which
  48    --  may well permit a larger range of times (this is explicitly allowed
  49    --  in Ada 95).
  50
  51    subtype Year_Number  is Integer range 1901 .. 2399;
  52    subtype Month_Number is Integer range 1 .. 12;
  53    subtype Day_Number   is Integer range 1 .. 31;
  54
  55    subtype Day_Duration is Duration range 0.0 .. 86_400.0;
  56
  57    function Clock return Time;
  58
  59    function Year    (Date : Time) return Year_Number;
  60    function Month   (Date : Time) return Month_Number;
  61    function Day     (Date : Time) return Day_Number;
  62    function Seconds (Date : Time) return Day_Duration;
  63
  64    procedure Split
  65      (Date    : Time;
  66       Year    : out Year_Number;
  67       Month   : out Month_Number;
  68       Day     : out Day_Number;
  69       Seconds : out Day_Duration);
  70
  71    function Time_Of
  72      (Year    : Year_Number;
  73       Month   : Month_Number;
  74       Day     : Day_Number;
  75       Seconds : Day_Duration := 0.0) return Time;
  76
  77    function "+" (Left : Time;     Right : Duration) return Time;
  78    function "+" (Left : Duration; Right : Time)     return Time;
  79    function "-" (Left : Time;     Right : Duration) return Time;
  80    function "-" (Left : Time;     Right : Time)     return Duration;
  81
  82    function "<"  (Left, Right : Time) return Boolean;
  83    function "<=" (Left, Right : Time) return Boolean;
  84    function ">"  (Left, Right : Time) return Boolean;
  85    function ">=" (Left, Right : Time) return Boolean;
  86
  87    Time_Error : exception;
  88
  89 private
  90    pragma Inline (Clock);
  91
  92    pragma Inline (Year);
  93    pragma Inline (Month);
  94    pragma Inline (Day);
  95
  96    pragma Inline ("+");
  97    pragma Inline ("-");
  98
  99    pragma Inline ("<");
 100    pragma Inline ("<=");
 101    pragma Inline (">");
 102    pragma Inline (">=");
 103
 104    --  Although the units are 100 nanoseconds, for the purpose of better
 105    --  readability, this unit will be called "mili".
 106
 107    Mili         : constant := 10_000_000;
 108    Mili_F       : constant := 10_000_000.0;
 109    Milis_In_Day : constant := 864_000_000_000;
 110    Secs_In_Day  : constant := 86_400;
 111
 112    --  Time is represented as the number of 100-nanosecond (ns) units from the
 113    --  system base date and time 1858-11-17 0.0 (the Smithsonian base date and
 114    --  time for the astronomic calendar).
 115
 116    --  The time value stored is typically a UTC value, as provided in standard
 117    --  Unix environments. If this is the case then Split and Time_Of perform
 118    --  required conversions to and from local times.
 119
 120    --  Notwithstanding this definition, Time is not quite the same as OS_Time.
 121    --  Relative Time is positive, whereas relative OS_Time is negative,
 122    --  but this declaration makes for easier conversion.
 123
 124    type Time is new OSP.OS_Time;
 125
 126    Days_In_Month : constant array (Month_Number) of Day_Number :=
 127                      (31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31);
 128
 129    Invalid_Time_Zone_Offset : Long_Integer;
 130    pragma Import (C, Invalid_Time_Zone_Offset, "__gnat_invalid_tzoff");
 131
 132    function Is_Leap (Year : Year_Number) return Boolean;
 133    --  Determine whether a given year is leap
 134
 135    --  The following packages provide a target independent interface to the
 136    --  children of Calendar - Arithmetic, Formatting and Time_Zones.
 137
 138    --  NOTE: Delays does not need a target independent interface because
 139    --  VMS already has a target specific file for that package.
 140
 141    ---------------------------
 142    -- Arithmetic_Operations --
 143    ---------------------------
 144
 145    package Arithmetic_Operations is
 146
 147       function Add (Date : Time; Days : Long_Integer) return Time;
 148       --  Add a certain number of days to a time value
 149
 150       procedure Difference
 151         (Left         : Time;
 152          Right        : Time;
 153          Days         : out Long_Integer;
 154          Seconds      : out Duration;
 155          Leap_Seconds : out Integer);
 156       --  Calculate the difference between two time values in terms of days,
 157       --  seconds and leap seconds elapsed. The leap seconds are not included
 158       --  in the seconds returned. If Left is greater than Right, the returned
 159       --  values are positive, negative otherwise.
 160
 161       function Subtract (Date : Time; Days : Long_Integer) return Time;
 162       --  Subtract a certain number of days from a time value
 163
 164    end Arithmetic_Operations;
 165
 166    ---------------------------
 167    -- Conversion_Operations --
 168    ---------------------------
 169
 170    package Conversion_Operations is
 171       function To_Ada_Time (Unix_Time : Long_Integer) return Time;
 172       --  Unix to Ada Epoch conversion
 173
 174       function To_Ada_Time
 175         (tm_year  : Integer;
 176          tm_mon   : Integer;
 177          tm_day   : Integer;
 178          tm_hour  : Integer;
 179          tm_min   : Integer;
 180          tm_sec   : Integer;
 181          tm_isdst : Integer) return Time;
 182       --  Struct tm to Ada Epoch conversion
 183
 184       function To_Duration
 185         (tv_sec  : Long_Integer;
 186          tv_nsec : Long_Integer) return Duration;
 187       --  Struct timespec to Duration conversion
 188
 189       procedure To_Struct_Timespec
 190         (D       : Duration;
 191          tv_sec  : out Long_Integer;
 192          tv_nsec : out Long_Integer);
 193       --  Duration to struct timespec conversion
 194
 195       procedure To_Struct_Tm
 196         (T       : Time;
 197          tm_year : out Integer;
 198          tm_mon  : out Integer;
 199          tm_day  : out Integer;
 200          tm_hour : out Integer;
 201          tm_min  : out Integer;
 202          tm_sec  : out Integer);
 203       --  Time to struct tm conversion
 204
 205       function To_Unix_Time (Ada_Time : Time) return Long_Integer;
 206       --  Ada to Unix Epoch conversion
 207
 208    end Conversion_Operations;
 209
 210    ---------------------------
 211    -- Formatting_Operations --
 212    ---------------------------
 213
 214    package Formatting_Operations is
 215
 216       function Day_Of_Week (Date : Time) return Integer;
 217       --  Determine which day of week Date falls on. The returned values are
 218       --  within the range of 0 .. 6 (Monday .. Sunday).
 219
 220       procedure Split
 221         (Date      : Time;
 222          Year      : out Year_Number;
 223          Month     : out Month_Number;
 224          Day       : out Day_Number;
 225          Day_Secs  : out Day_Duration;
 226          Hour      : out Integer;
 227          Minute    : out Integer;
 228          Second    : out Integer;
 229          Sub_Sec   : out Duration;
 230          Leap_Sec  : out Boolean;
 231          Is_Ada_05 : Boolean;
 232          Time_Zone : Long_Integer);
 233       --  Split a time value into its components. Set Is_Ada_05 to use the
 234       --  local time zone (the value in Time_Zone is ignored) when splitting
 235       --  a time value.
 236
 237       function Time_Of
 238         (Year         : Year_Number;
 239          Month        : Month_Number;
 240          Day          : Day_Number;
 241          Day_Secs     : Day_Duration;
 242          Hour         : Integer;
 243          Minute       : Integer;
 244          Second       : Integer;
 245          Sub_Sec      : Duration;
 246          Leap_Sec     : Boolean := False;
 247          Use_Day_Secs : Boolean := False;
 248          Is_Ada_05    : Boolean := False;
 249          Time_Zone    : Long_Integer := 0) return Time;
 250       --  Given all the components of a date, return the corresponding time
 251       --  value. Set Use_Day_Secs to use the value in Day_Secs, otherwise the
 252       --  day duration will be calculated from Hour, Minute, Second and Sub_
 253       --  Sec. Set Is_Ada_05 to use the local time zone (the value in formal
 254       --  Time_Zone is ignored) when building a time value and to verify the
 255       --  validity of a requested leap second.
 256
 257    end Formatting_Operations;
 258
 259    ---------------------------
 260    -- Time_Zones_Operations --
 261    ---------------------------
 262
 263    package Time_Zones_Operations is
 264
 265       function UTC_Time_Offset (Date : Time) return Long_Integer;
 266       --  Return the offset in seconds from UTC
 267
 268    end Time_Zones_Operations;
 269
 270 end Ada.Calendar;