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 --                             $Revision: 1.18 $
  10 --                                                                          --
  11 --             Copyright (C) 1991-2000 Florida State University             --
  12 --                                                                          --
  13 -- GNARL is free software; you can  redistribute it  and/or modify it under --
  14 -- terms of the  GNU General Public License as published  by the Free Soft- --
  15 -- ware  Foundation;  either version 2,  or (at your option) any later ver- --
  16 -- sion. GNARL is distributed in the hope that it will be useful, but WITH- --
  17 -- OUT ANY WARRANTY;  without even the  implied warranty of MERCHANTABILITY --
  18 -- or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License --
  19 -- for  more details.  You should have  received  a copy of the GNU General --
  20 -- Public License  distributed with GNARL; see file COPYING.  If not, write --
  21 -- to  the Free Software Foundation,  59 Temple Place - Suite 330,  Boston, --
  22 -- MA 02111-1307, USA.                                                      --
  23 --                                                                          --
  24 -- As a special exception,  if other files  instantiate  generics from this --
  25 -- unit, or you link  this unit with other files  to produce an executable, --
  26 -- this  unit  does not  by itself cause  the resulting  executable  to  be --
  27 -- covered  by the  GNU  General  Public  License.  This exception does not --
  28 -- however invalidate  any other reasons why  the executable file  might be --
  29 -- covered by the  GNU Public License.                                      --
  30 --                                                                          --
  31 -- GNARL was developed by the GNARL team at Florida State University. It is --
  32 -- now maintained by Ada Core Technologies Inc. in cooperation with Florida --
  33 -- State University (http://www.gnat.com).                                  --
  34 --                                                                          --
  35 ------------------------------------------------------------------------------
  36
  37 --  This is the Alpha/VMS version.
  38
  39 with System.OS_Primitives;
  40 --  Used for Max_Sensible_Delay
  41
  42 with System.Soft_Links;
  43 --  Used for Timed_Delay
  44
  45 package body Ada.Calendar.Delays is
  46
  47    package OSP renames System.OS_Primitives;
  48    package TSL renames System.Soft_Links;
  49
  50    use type TSL.Timed_Delay_Call;
  51
  52    ---------------
  53    -- Delay_For --
  54    ---------------
  55
  56    procedure Delay_For (D : Duration) is
  57    begin
  58       TSL.Timed_Delay.all
  59         (Duration'Min (D, OSP.Max_Sensible_Delay), OSP.Relative);
  60    end Delay_For;
  61
  62    -----------------
  63    -- Delay_Until --
  64    -----------------
  65
  66    procedure Delay_Until (T : Time) is
  67    begin
  68       TSL.Timed_Delay.all (To_Duration (T), OSP.Absolute_Calendar);
  69    end Delay_Until;
  70
  71    -----------------
  72    -- To_Duration --
  73    -----------------
  74
  75    function To_Duration (T : Time) return Duration is
  76    begin
  77       return OSP.To_Duration (OSP.OS_Time (T), OSP.Absolute_Calendar);
  78    end To_Duration;
  79
  80    --------------------
  81    -- Timed_Delay_NT --
  82    --------------------
  83
  84    procedure Timed_Delay_NT (Time : Duration; Mode : Integer);
  85
  86    procedure Timed_Delay_NT (Time : Duration; Mode : Integer) is
  87    begin
  88       OSP.Timed_Delay (Time, Mode);
  89    end Timed_Delay_NT;
  90
  91 begin
  92    --  Set up the Timed_Delay soft link to the non tasking version if it has
  93    --  not been already set.
  94    --  If tasking is present, Timed_Delay has already set this soft link, or
  95    --  this will be overriden during the elaboration of
  96    --  System.Tasking.Initialization
  97
  98    if TSL.Timed_Delay = null then
  99       TSL.Timed_Delay := Timed_Delay_NT'Access;
 100    end if;
 101 end Ada.Calendar.Delays;