1 ------------------------------------------------------------------------------
3 -- GNU ADA RUN-TIME LIBRARY (GNARL) COMPONENTS --
5 -- S Y S T E M . O S _ P R I M I T I V E S --
10 -- Copyright (C) 1998-2001 Free Software Foundation, Inc. --
12 -- GNARL is free software; you can redistribute it and/or modify it under --
13 -- terms of the GNU General Public License as published by the Free Soft- --
14 -- ware Foundation; either version 2, or (at your option) any later ver- --
15 -- sion. GNARL is distributed in the hope that it will be useful, but WITH- --
16 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
17 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
18 -- for more details. You should have received a copy of the GNU General --
19 -- Public License distributed with GNARL; see file COPYING. If not, write --
20 -- to the Free Software Foundation, 59 Temple Place - Suite 330, Boston, --
21 -- MA 02111-1307, USA. --
23 -- As a special exception, if other files instantiate generics from this --
24 -- unit, or you link this unit with other files to produce an executable, --
25 -- this unit does not by itself cause the resulting executable to be --
26 -- covered by the GNU General Public License. This exception does not --
27 -- however invalidate any other reasons why the executable file might be --
28 -- covered by the GNU Public License. --
30 -- GNARL was developed by the GNARL team at Florida State University. It is --
31 -- now maintained by Ada Core Technologies Inc. in cooperation with Florida --
32 -- State University (http://www.gnat.com). --
34 ------------------------------------------------------------------------------
36 -- This is the OpenVMS/Alpha version of this file
40 package body System.OS_Primitives is
42 --------------------------------------
43 -- Local functions and declarations --
44 --------------------------------------
46 function Get_GMToff return Integer;
47 pragma Import (C, Get_GMToff, "get_gmtoff");
48 -- Get the offset from GMT for this timezone
50 VMS_Epoch_Offset : constant Long_Integer :=
52 (3_506_716_800 + Long_Integer (Get_GMToff));
53 -- The offset between the Unix Epoch and the VMS Epoch
55 subtype Cond_Value_Type is System.Aux_DEC.Unsigned_Longword;
56 -- Condition Value return type
64 -- status = returned status
65 -- pidadr = address of process id to be woken up
66 -- prcnam = name of process to be woken up
67 -- daytim = time to wake up
68 -- reptim = repitition interval of wakeup calls
73 Status : out Cond_Value_Type;
74 Pidadr : in Address := Null_Address;
75 Prcnam : in String := String'Null_Parameter;
76 Daytim : in Long_Integer;
77 Reptim : in Long_Integer := Long_Integer'Null_Parameter
80 pragma Interface (External, Sys_Schdwk);
81 -- VMS system call to schedule a wakeup event
82 pragma Import_Valued_Procedure
83 (Sys_Schdwk, "SYS$SCHDWK",
84 (Cond_Value_Type, Address, String, Long_Integer, Long_Integer),
85 (Value, Value, Descriptor (S), Reference, Reference)
94 -- status = returned status
95 -- tim = current system time
100 Status : out Cond_Value_Type;
103 -- VMS system call to get the current system time
104 pragma Interface (External, Sys_Gettim);
105 pragma Import_Valued_Procedure
106 (Sys_Gettim, "SYS$GETTIM",
107 (Cond_Value_Type, OS_Time),
115 -- Hibernate (until woken up)
117 -- status = returned status
120 procedure Sys_Hiber (Status : out Cond_Value_Type);
121 -- VMS system call to hibernate the current process
122 pragma Interface (External, Sys_Hiber);
123 pragma Import_Valued_Procedure
124 (Sys_Hiber, "SYS$HIBER",
133 function OS_Clock return OS_Time is
134 Status : Cond_Value_Type;
137 Sys_Gettim (Status, T);
145 function Clock return Duration is
147 return To_Duration (OS_Clock, Absolute_Calendar);
150 ---------------------
151 -- Monotonic_Clock --
152 ---------------------
154 function Monotonic_Clock return Duration renames Clock;
160 procedure Timed_Delay
164 Sleep_Time : OS_Time;
165 Status : Cond_Value_Type;
168 Sleep_Time := To_OS_Time (Time, Mode);
169 Sys_Schdwk (Status => Status, Daytim => Sleep_Time);
177 function To_Duration (T : OS_Time; Mode : Integer) return Duration is
179 return Duration'Fixed_Value (T - VMS_Epoch_Offset) * 100;
186 function To_OS_Time (D : Duration; Mode : Integer) return OS_Time is
188 if Mode = Relative then
189 return -(Long_Integer'Integer_Value (D) / 100);
191 return Long_Integer'Integer_Value (D) / 100 + VMS_Epoch_Offset;
195 end System.OS_Primitives;