gcc/ada/4vcaldel.adb

   1 ------------------------------------------------------------------------------
   2 --                                                                          --
   3 --                GNU ADA RUN-TIME LIBRARY (GNARL) COMPONENTS               --
   4 --                                                                          --
   5 --                   A D A . C A L E N D A R . D E L A Y S                  --
   6 --                                                                          --
   7 --                                  B o d y                                 --
   8 --                                                                          --
   9 --             Copyright (C) 1991-2000 Florida State University             --
  10 --                                                                          --
  11 -- GNARL is free software; you can  redistribute it  and/or modify it under --
  12 -- terms of the  GNU General Public License as published  by the Free Soft- --
  13 -- ware  Foundation;  either version 2,  or (at your option) any later ver- --
  14 -- sion. GNARL is distributed in the hope that it will be useful, but WITH- --
  15 -- OUT ANY WARRANTY;  without even the  implied warranty of MERCHANTABILITY --
  16 -- or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License --
  17 -- for  more details.  You should have  received  a copy of the GNU General --
  18 -- Public License  distributed with GNARL; see file COPYING.  If not, write --
  19 -- to  the Free Software Foundation,  59 Temple Place - Suite 330,  Boston, --
  20 -- MA 02111-1307, USA.                                                      --
  21 --                                                                          --
  22 -- As a special exception,  if other files  instantiate  generics from this --
  23 -- unit, or you link  this unit with other files  to produce an executable, --
  24 -- this  unit  does not  by itself cause  the resulting  executable  to  be --
  25 -- covered  by the  GNU  General  Public  License.  This exception does not --
  26 -- however invalidate  any other reasons why  the executable file  might be --
  27 -- covered by the  GNU Public License.                                      --
  28 --                                                                          --
  29 -- GNARL was developed by the GNARL team at Florida State University. It is --
  30 -- now maintained by Ada Core Technologies Inc. in cooperation with Florida --
  31 -- State University (http://www.gnat.com).                                  --
  32 --                                                                          --
  33 ------------------------------------------------------------------------------
  34
  35 --  This is the Alpha/VMS version.
  36
  37 with System.OS_Primitives;
  38 --  Used for Max_Sensible_Delay
  39
  40 with System.Soft_Links;
  41 --  Used for Timed_Delay
  42
  43 package body Ada.Calendar.Delays is
  44
  45    package OSP renames System.OS_Primitives;
  46    package TSL renames System.Soft_Links;
  47
  48    use type TSL.Timed_Delay_Call;
  49
  50    ---------------
  51    -- Delay_For --
  52    ---------------
  53
  54    procedure Delay_For (D : Duration) is
  55    begin
  56       TSL.Timed_Delay.all
  57         (Duration'Min (D, OSP.Max_Sensible_Delay), OSP.Relative);
  58    end Delay_For;
  59
  60    -----------------
  61    -- Delay_Until --
  62    -----------------
  63
  64    procedure Delay_Until (T : Time) is
  65    begin
  66       TSL.Timed_Delay.all (To_Duration (T), OSP.Absolute_Calendar);
  67    end Delay_Until;
  68
  69    -----------------
  70    -- To_Duration --
  71    -----------------
  72
  73    function To_Duration (T : Time) return Duration is
  74    begin
  75       return OSP.To_Duration (OSP.OS_Time (T), OSP.Absolute_Calendar);
  76    end To_Duration;
  77
  78    --------------------
  79    -- Timed_Delay_NT --
  80    --------------------
  81
  82    procedure Timed_Delay_NT (Time : Duration; Mode : Integer);
  83
  84    procedure Timed_Delay_NT (Time : Duration; Mode : Integer) is
  85    begin
  86       OSP.Timed_Delay (Time, Mode);
  87    end Timed_Delay_NT;
  88
  89 begin
  90    --  Set up the Timed_Delay soft link to the non tasking version if it has
  91    --  not been already set.
  92    --  If tasking is present, Timed_Delay has already set this soft link, or
  93    --  this will be overriden during the elaboration of
  94    --  System.Tasking.Initialization
  95
  96    if TSL.Timed_Delay = null then
  97       TSL.Timed_Delay := Timed_Delay_NT'Access;
  98    end if;
  99 end Ada.Calendar.Delays;