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 --
9 -- Copyright (C) 1998-2002 Free Software Foundation, Inc. --
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. --
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. --
29 -- GNARL was developed by the GNARL team at Florida State University. --
30 -- Extensive contributions were provided by Ada Core Technologies, Inc. --
32 ------------------------------------------------------------------------------
34 -- This is the OpenVMS/Alpha version of this file
38 package body System.OS_Primitives is
40 --------------------------------------
41 -- Local functions and declarations --
42 --------------------------------------
44 function Get_GMToff return Integer;
45 pragma Import (C, Get_GMToff, "get_gmtoff");
46 -- Get the offset from GMT for this timezone
48 VMS_Epoch_Offset : constant Long_Integer :=
50 (3_506_716_800 + Long_Integer (Get_GMToff));
51 -- The offset between the Unix Epoch and the VMS Epoch
53 subtype Cond_Value_Type is System.Aux_DEC.Unsigned_Longword;
54 -- Condition Value return type
62 -- status = returned status
63 -- pidadr = address of process id to be woken up
64 -- prcnam = name of process to be woken up
65 -- daytim = time to wake up
66 -- reptim = repitition interval of wakeup calls
71 Status : out Cond_Value_Type;
72 Pidadr : in Address := Null_Address;
73 Prcnam : in String := String'Null_Parameter;
74 Daytim : in Long_Integer;
75 Reptim : in Long_Integer := Long_Integer'Null_Parameter
78 pragma Interface (External, Sys_Schdwk);
79 -- VMS system call to schedule a wakeup event
80 pragma Import_Valued_Procedure
81 (Sys_Schdwk, "SYS$SCHDWK",
82 (Cond_Value_Type, Address, String, Long_Integer, Long_Integer),
83 (Value, Value, Descriptor (S), Reference, Reference)
92 -- status = returned status
93 -- tim = current system time
98 Status : out Cond_Value_Type;
101 -- VMS system call to get the current system time
102 pragma Interface (External, Sys_Gettim);
103 pragma Import_Valued_Procedure
104 (Sys_Gettim, "SYS$GETTIM",
105 (Cond_Value_Type, OS_Time),
113 -- Hibernate (until woken up)
115 -- status = returned status
117 procedure Sys_Hiber (Status : out Cond_Value_Type);
118 -- VMS system call to hibernate the current process
119 pragma Interface (External, Sys_Hiber);
120 pragma Import_Valued_Procedure
121 (Sys_Hiber, "SYS$HIBER",
130 function OS_Clock return OS_Time is
131 Status : Cond_Value_Type;
134 Sys_Gettim (Status, T);
142 function Clock return Duration is
144 return To_Duration (OS_Clock, Absolute_Calendar);
147 ---------------------
148 -- Monotonic_Clock --
149 ---------------------
151 function Monotonic_Clock return Duration renames Clock;
157 procedure Timed_Delay
161 Sleep_Time : OS_Time;
162 Status : Cond_Value_Type;
165 Sleep_Time := To_OS_Time (Time, Mode);
166 Sys_Schdwk (Status => Status, Daytim => Sleep_Time);
174 function To_Duration (T : OS_Time; Mode : Integer) return Duration is
175 pragma Warnings (Off, Mode);
177 return Duration'Fixed_Value (T - VMS_Epoch_Offset) * 100;
184 function To_OS_Time (D : Duration; Mode : Integer) return OS_Time is
186 if Mode = Relative then
187 return -(Long_Integer'Integer_Value (D) / 100);
189 return Long_Integer'Integer_Value (D) / 100 + VMS_Epoch_Offset;
193 end System.OS_Primitives;