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------------------------------------------------------------------------------
-- --
-- GNU ADA RUN-TIME LIBRARY (GNARL) COMPONENTS --
-- --
-- S Y S T E M . T A S K _ P R I M I T I V E S . O P E R A T I O N S --
-- --
-- B o d y --
-- --
-- $Revision: 1.1 $
-- --
-- Copyright (C) 1991-2001, Florida State University --
-- --
-- GNARL is free software; you can redistribute it and/or modify it under --
-- terms of the GNU General Public License as published by the Free Soft- --
-- ware Foundation; either version 2, or (at your option) any later ver- --
-- sion. GNARL is distributed in the hope that it will be useful, but WITH- --
-- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
-- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
-- for more details. You should have received a copy of the GNU General --
-- Public License distributed with GNARL; see file COPYING. If not, write --
-- to the Free Software Foundation, 59 Temple Place - Suite 330, Boston, --
-- MA 02111-1307, USA. --
-- --
-- As a special exception, if other files instantiate generics from this --
-- unit, or you link this unit with other files to produce an executable, --
-- this unit does not by itself cause the resulting executable to be --
-- covered by the GNU General Public License. This exception does not --
-- however invalidate any other reasons why the executable file might be --
-- covered by the GNU Public License. --
-- --
-- GNARL was developed by the GNARL team at Florida State University. It is --
-- now maintained by Ada Core Technologies Inc. in cooperation with Florida --
-- State University (http://www.gnat.com). --
-- --
------------------------------------------------------------------------------
-- This is a OpenVMS/Alpha version of this package
-- This package contains all the GNULL primitives that interface directly
-- with the underlying OS.
pragma Polling (Off);
-- Turn off polling, we do not want ATC polling to take place during
-- tasking operations. It causes infinite loops and other problems.
with System.Tasking.Debug;
-- used for Known_Tasks
with Interfaces.C;
-- used for int
-- size_t
with System.Parameters;
-- used for Size_Type
with System.Tasking;
-- used for Ada_Task_Control_Block
-- Task_ID
with System.Soft_Links;
-- used for Defer/Undefer_Abort
-- Set_Exc_Stack_Addr
-- Note that we do not use System.Tasking.Initialization directly since
-- this is a higher level package that we shouldn't depend on. For example
-- when using the restricted run time, it is replaced by
-- System.Tasking.Restricted.Initialization
with System.OS_Primitives;
-- used for Delay_Modes
with Unchecked_Conversion;
with Unchecked_Deallocation;
package body System.Task_Primitives.Operations is
use System.Tasking.Debug;
use System.Tasking;
use Interfaces.C;
use System.OS_Interface;
use System.Parameters;
use System.OS_Primitives;
use type System.OS_Primitives.OS_Time;
package SSL renames System.Soft_Links;
------------------
-- Local Data --
------------------
-- The followings are logically constants, but need to be initialized
-- at run time.
ATCB_Key : aliased pthread_key_t;
-- Key used to find the Ada Task_ID associated with a thread
All_Tasks_L : aliased System.Task_Primitives.RTS_Lock;
-- See comments on locking rules in System.Tasking (spec).
Environment_Task_ID : Task_ID;
-- A variable to hold Task_ID for the environment task.
Time_Slice_Val : Integer;
pragma Import (C, Time_Slice_Val, "__gl_time_slice_val");
Dispatching_Policy : Character;
pragma Import (C, Dispatching_Policy, "__gl_task_dispatching_policy");
FIFO_Within_Priorities : constant Boolean := Dispatching_Policy = 'F';
-- Indicates whether FIFO_Within_Priorities is set.
-----------------------
-- Local Subprograms --
-----------------------
function To_Task_ID is new Unchecked_Conversion (System.Address, Task_ID);
function To_Address is new Unchecked_Conversion (Task_ID, System.Address);
procedure Timer_Sleep_AST (ID : Address);
-- Signal the condition variable when AST fires.
procedure Timer_Sleep_AST (ID : Address) is
Result : Interfaces.C.int;
Self_ID : Task_ID := To_Task_ID (ID);
begin
Self_ID.Common.LL.AST_Pending := False;
Result := pthread_cond_signal_int_np (Self_ID.Common.LL.CV'Access);
end Timer_Sleep_AST;
-------------------
-- Stack_Guard --
-------------------
-- The underlying thread system sets a guard page at the
-- bottom of a thread stack, so nothing is needed.
-- ??? Check the comment above
procedure Stack_Guard (T : ST.Task_ID; On : Boolean) is
begin
null;
end Stack_Guard;
--------------------
-- Get_Thread_Id --
--------------------
function Get_Thread_Id (T : ST.Task_ID) return OSI.Thread_Id is
begin
return T.Common.LL.Thread;
end Get_Thread_Id;
----------
-- Self --
----------
function Self return Task_ID is
Result : System.Address;
begin
Result := pthread_getspecific (ATCB_Key);
pragma Assert (Result /= System.Null_Address);
return To_Task_ID (Result);
end Self;
---------------------
-- Initialize_Lock --
---------------------
-- Note: mutexes and cond_variables needed per-task basis are
-- initialized in Initialize_TCB and the Storage_Error is
-- handled. Other mutexes (such as All_Tasks_Lock, Memory_Lock...)
-- used in RTS is initialized before any status change of RTS.
-- Therefore rasing Storage_Error in the following routines
-- should be able to be handled safely.
procedure Initialize_Lock (Prio : System.Any_Priority; L : access Lock) is
Attributes : aliased pthread_mutexattr_t;
Result : Interfaces.C.int;
begin
Result := pthread_mutexattr_init (Attributes'Access);
pragma Assert (Result = 0 or else Result = ENOMEM);
if Result = ENOMEM then
raise Storage_Error;
end if;
L.Prio_Save := 0;
L.Prio := Interfaces.C.int (Prio);
Result := pthread_mutex_init (L.L'Access, Attributes'Access);
pragma Assert (Result = 0 or else Result = ENOMEM);
if Result = ENOMEM then
raise Storage_Error;
end if;
Result := pthread_mutexattr_destroy (Attributes'Access);
pragma Assert (Result = 0);
end Initialize_Lock;
procedure Initialize_Lock (L : access RTS_Lock; Level : Lock_Level) is
Attributes : aliased pthread_mutexattr_t;
Result : Interfaces.C.int;
begin
Result := pthread_mutexattr_init (Attributes'Access);
pragma Assert (Result = 0 or else Result = ENOMEM);
if Result = ENOMEM then
raise Storage_Error;
end if;
-- Don't use, see comment in s-osinte.ads about ERRORCHECK mutexes.
-- Result := pthread_mutexattr_settype_np
-- (Attributes'Access, PTHREAD_MUTEX_ERRORCHECK_NP);
-- pragma Assert (Result = 0);
-- Result := pthread_mutexattr_setprotocol
-- (Attributes'Access, PTHREAD_PRIO_PROTECT);
-- pragma Assert (Result = 0);
-- Result := pthread_mutexattr_setprioceiling
-- (Attributes'Access, Interfaces.C.int (System.Any_Priority'Last));
-- pragma Assert (Result = 0);
Result := pthread_mutex_init (L, Attributes'Access);
pragma Assert (Result = 0 or else Result = ENOMEM);
if Result = ENOMEM then
raise Storage_Error;
end if;
Result := pthread_mutexattr_destroy (Attributes'Access);
pragma Assert (Result = 0);
end Initialize_Lock;
-------------------
-- Finalize_Lock --
-------------------
procedure Finalize_Lock (L : access Lock) is
Result : Interfaces.C.int;
begin
Result := pthread_mutex_destroy (L.L'Access);
pragma Assert (Result = 0);
end Finalize_Lock;
procedure Finalize_Lock (L : access RTS_Lock) is
Result : Interfaces.C.int;
begin
Result := pthread_mutex_destroy (L);
pragma Assert (Result = 0);
end Finalize_Lock;
----------------
-- Write_Lock --
----------------
procedure Write_Lock (L : access Lock; Ceiling_Violation : out Boolean) is
Self_ID : constant Task_ID := Self;
All_Tasks_Link : constant Task_ID := Self.Common.All_Tasks_Link;
Current_Prio : System.Any_Priority;
Result : Interfaces.C.int;
begin
Current_Prio := Get_Priority (Self_ID);
-- If there is no other tasks, no need to check priorities.
if All_Tasks_Link /= Null_Task
and then L.Prio < Interfaces.C.int (Current_Prio)
then
Ceiling_Violation := True;
return;
end if;
Result := pthread_mutex_lock (L.L'Access);
pragma Assert (Result = 0);
Ceiling_Violation := False;
-- Why is this commented out ???
-- L.Prio_Save := Interfaces.C.int (Current_Prio);
-- Set_Priority (Self_ID, System.Any_Priority (L.Prio));
end Write_Lock;
procedure Write_Lock (L : access RTS_Lock) is
Result : Interfaces.C.int;
begin
Result := pthread_mutex_lock (L);
pragma Assert (Result = 0);
end Write_Lock;
procedure Write_Lock (T : Task_ID) is
Result : Interfaces.C.int;
begin
Result := pthread_mutex_lock (T.Common.LL.L'Access);
pragma Assert (Result = 0);
end Write_Lock;
---------------
-- Read_Lock --
---------------
procedure Read_Lock (L : access Lock; Ceiling_Violation : out Boolean) is
begin
Write_Lock (L, Ceiling_Violation);
end Read_Lock;
------------
-- Unlock --
------------
procedure Unlock (L : access Lock) is
Result : Interfaces.C.int;
begin
Result := pthread_mutex_unlock (L.L'Access);
pragma Assert (Result = 0);
end Unlock;
procedure Unlock (L : access RTS_Lock) is
Result : Interfaces.C.int;
begin
Result := pthread_mutex_unlock (L);
pragma Assert (Result = 0);
end Unlock;
procedure Unlock (T : Task_ID) is
Result : Interfaces.C.int;
begin
Result := pthread_mutex_unlock (T.Common.LL.L'Access);
pragma Assert (Result = 0);
end Unlock;
-------------
-- Sleep --
-------------
procedure Sleep (Self_ID : Task_ID;
Reason : System.Tasking.Task_States) is
Result : Interfaces.C.int;
begin
pragma Assert (Self_ID = Self);
Result := pthread_cond_wait (Self_ID.Common.LL.CV'Access,
Self_ID.Common.LL.L'Access);
-- EINTR is not considered a failure.
pragma Assert (Result = 0 or else Result = EINTR);
if Self_ID.Deferral_Level = 0
and then Self_ID.Pending_ATC_Level < Self_ID.ATC_Nesting_Level
then
Unlock (Self_ID);
raise Standard'Abort_Signal;
end if;
end Sleep;
-----------------
-- Timed_Sleep --
-----------------
-- This is for use within the run-time system, so abort is
-- assumed to be already deferred, and the caller should be
-- holding its own ATCB lock.
procedure Timed_Sleep
(Self_ID : Task_ID;
Time : Duration;
Mode : ST.Delay_Modes;
Reason : System.Tasking.Task_States;
Timedout : out Boolean;
Yielded : out Boolean)
is
Sleep_Time : OS_Time;
Result : Interfaces.C.int;
Status : Cond_Value_Type;
begin
Timedout := False;
Yielded := False;
Sleep_Time := To_OS_Time (Time, Mode);
if Self_ID.Pending_ATC_Level < Self_ID.ATC_Nesting_Level
or else Self_ID.Pending_Priority_Change
then
return;
end if;
Self_ID.Common.LL.AST_Pending := True;
Sys_Setimr
(Status, 0, Sleep_Time,
Timer_Sleep_AST'Access, To_Address (Self_ID), 0);
if (Status and 1) /= 1 then
raise Storage_Error;
end if;
Result := pthread_cond_wait (Self_ID.Common.LL.CV'Access,
Self_ID.Common.LL.L'Access);
if not Self_ID.Common.LL.AST_Pending then
Timedout := True;
else
Sys_Cantim (Status, To_Address (Self_ID), 0);
pragma Assert ((Status and 1) = 1);
end if;
end Timed_Sleep;
-----------------
-- Timed_Delay --
-----------------
-- This is for use in implementing delay statements, so
-- we assume the caller is abort-deferred but is holding
-- no locks.
procedure Timed_Delay
(Self_ID : Task_ID;
Time : Duration;
Mode : ST.Delay_Modes)
is
Sleep_Time : OS_Time;
Result : Interfaces.C.int;
Status : Cond_Value_Type;
begin
-- Only the little window between deferring abort and
-- locking Self_ID is the reason we need to
-- check for pending abort and priority change below! :(
SSL.Abort_Defer.all;
Write_Lock (Self_ID);
if not (Time = 0.0 and then Mode = Relative) then
Sleep_Time := To_OS_Time (Time, Mode);
if Mode = Relative or else OS_Clock < Sleep_Time then
Self_ID.Common.State := Delay_Sleep;
Self_ID.Common.LL.AST_Pending := True;
Sys_Setimr
(Status, 0, Sleep_Time,
Timer_Sleep_AST'Access, To_Address (Self_ID), 0);
if (Status and 1) /= 1 then
raise Storage_Error;
end if;
loop
if Self_ID.Pending_Priority_Change then
Self_ID.Pending_Priority_Change := False;
Self_ID.Common.Base_Priority := Self_ID.New_Base_Priority;
Set_Priority (Self_ID, Self_ID.Common.Base_Priority);
end if;
if Self_ID.Pending_ATC_Level < Self_ID.ATC_Nesting_Level then
Sys_Cantim (Status, To_Address (Self_ID), 0);
pragma Assert ((Status and 1) = 1);
exit;
end if;
Result := pthread_cond_wait (Self_ID.Common.LL.CV'Access,
Self_ID.Common.LL.L'Access);
exit when not Self_ID.Common.LL.AST_Pending;
end loop;
Self_ID.Common.State := Runnable;
end if;
end if;
Unlock (Self_ID);
Result := sched_yield;
SSL.Abort_Undefer.all;
end Timed_Delay;
---------------------
-- Monotonic_Clock --
---------------------
function Monotonic_Clock return Duration
renames System.OS_Primitives.Monotonic_Clock;
-------------------
-- RT_Resolution --
-------------------
function RT_Resolution return Duration is
begin
return 10#1.0#E-3;
end RT_Resolution;
------------
-- Wakeup --
------------
procedure Wakeup (T : Task_ID; Reason : System.Tasking.Task_States) is
Result : Interfaces.C.int;
begin
Result := pthread_cond_signal (T.Common.LL.CV'Access);
pragma Assert (Result = 0);
end Wakeup;
-----------
-- Yield --
-----------
procedure Yield (Do_Yield : Boolean := True) is
Result : Interfaces.C.int;
begin
if Do_Yield then
Result := sched_yield;
end if;
end Yield;
------------------
-- Set_Priority --
------------------
procedure Set_Priority
(T : Task_ID;
Prio : System.Any_Priority;
Loss_Of_Inheritance : Boolean := False)
is
Result : Interfaces.C.int;
Param : aliased struct_sched_param;
begin
T.Common.Current_Priority := Prio;
Param.sched_priority := Interfaces.C.int (Underlying_Priorities (Prio));
if Time_Slice_Val > 0 then
Result := pthread_setschedparam
(T.Common.LL.Thread, SCHED_RR, Param'Access);
elsif FIFO_Within_Priorities or else Time_Slice_Val = 0 then
Result := pthread_setschedparam
(T.Common.LL.Thread, SCHED_FIFO, Param'Access);
else
Result := pthread_setschedparam
(T.Common.LL.Thread, SCHED_OTHER, Param'Access);
end if;
pragma Assert (Result = 0);
end Set_Priority;
------------------
-- Get_Priority --
------------------
function Get_Priority (T : Task_ID) return System.Any_Priority is
begin
return T.Common.Current_Priority;
end Get_Priority;
----------------
-- Enter_Task --
----------------
procedure Enter_Task (Self_ID : Task_ID) is
Result : Interfaces.C.int;
begin
Self_ID.Common.LL.Thread := pthread_self;
-- It is not safe for the new task accept signals until it
-- has bound its TCB pointer to the thread with pthread_setspecific (),
-- since the handler wrappers use the TCB pointer
-- to restore the stack limit.
Result := pthread_setspecific (ATCB_Key, To_Address (Self_ID));
pragma Assert (Result = 0);
Lock_All_Tasks_List;
for I in Known_Tasks'Range loop
if Known_Tasks (I) = null then
Known_Tasks (I) := Self_ID;
Self_ID.Known_Tasks_Index := I;
exit;
end if;
end loop;
Unlock_All_Tasks_List;
end Enter_Task;
--------------
-- New_ATCB --
--------------
function New_ATCB (Entry_Num : Task_Entry_Index) return Task_ID is
begin
return new Ada_Task_Control_Block (Entry_Num);
end New_ATCB;
----------------------
-- Initialize_TCB --
----------------------
procedure Initialize_TCB (Self_ID : Task_ID; Succeeded : out Boolean) is
Mutex_Attr : aliased pthread_mutexattr_t;
Result : Interfaces.C.int;
Cond_Attr : aliased pthread_condattr_t;
begin
Result := pthread_mutexattr_init (Mutex_Attr'Access);
pragma Assert (Result = 0 or else Result = ENOMEM);
if Result /= 0 then
Succeeded := False;
return;
end if;
-- Don't use, see comment in s-osinte.ads about ERRORCHECK mutexes.
-- Result := pthread_mutexattr_settype_np
-- (Mutex_Attr'Access, PTHREAD_MUTEX_ERRORCHECK_NP);
-- pragma Assert (Result = 0);
-- Result := pthread_mutexattr_setprotocol
-- (Mutex_Attr'Access, PTHREAD_PRIO_PROTECT);
-- pragma Assert (Result = 0);
-- Result := pthread_mutexattr_setprioceiling
-- (Mutex_Attr'Access, Interfaces.C.int (System.Any_Priority'Last));
-- pragma Assert (Result = 0);
Result := pthread_mutex_init (Self_ID.Common.LL.L'Access,
Mutex_Attr'Access);
pragma Assert (Result = 0 or else Result = ENOMEM);
if Result /= 0 then
Succeeded := False;
return;
end if;
Result := pthread_mutexattr_destroy (Mutex_Attr'Access);
pragma Assert (Result = 0);
Result := pthread_condattr_init (Cond_Attr'Access);
pragma Assert (Result = 0 or else Result = ENOMEM);
if Result /= 0 then
Result := pthread_mutex_destroy (Self_ID.Common.LL.L'Access);
pragma Assert (Result = 0);
Succeeded := False;
return;
end if;
Result := pthread_cond_init (Self_ID.Common.LL.CV'Access,
Cond_Attr'Access);
pragma Assert (Result = 0 or else Result = ENOMEM);
if Result = 0 then
Succeeded := True;
Self_ID.Common.LL.Exc_Stack_Ptr := new Exc_Stack_T;
SSL.Set_Exc_Stack_Addr
(To_Address (Self_ID),
Self_ID.Common.LL.Exc_Stack_Ptr (Exc_Stack_T'Last)'Address);
else
Result := pthread_mutex_destroy (Self_ID.Common.LL.L'Access);
pragma Assert (Result = 0);
Succeeded := False;
end if;
Result := pthread_condattr_destroy (Cond_Attr'Access);
pragma Assert (Result = 0);
end Initialize_TCB;
-----------------
-- Create_Task --
-----------------
procedure Create_Task
(T : Task_ID;
Wrapper : System.Address;
Stack_Size : System.Parameters.Size_Type;
Priority : System.Any_Priority;
Succeeded : out Boolean)
is
Attributes : aliased pthread_attr_t;
Adjusted_Stack_Size : Interfaces.C.size_t;
Result : Interfaces.C.int;
function Thread_Body_Access is new
Unchecked_Conversion (System.Address, Thread_Body);
begin
if Stack_Size = Unspecified_Size then
Adjusted_Stack_Size := Interfaces.C.size_t (Default_Stack_Size);
elsif Stack_Size < Minimum_Stack_Size then
Adjusted_Stack_Size := Interfaces.C.size_t (Minimum_Stack_Size);
else
Adjusted_Stack_Size := Interfaces.C.size_t (Stack_Size);
end if;
-- Since the initial signal mask of a thread is inherited from the
-- creator, we need to set our local signal mask mask all signals
-- during the creation operation, to make sure the new thread is
-- not disturbed by signals before it has set its own Task_ID.
Result := pthread_attr_init (Attributes'Access);
pragma Assert (Result = 0 or else Result = ENOMEM);
if Result /= 0 then
Succeeded := False;
return;
end if;
Result := pthread_attr_setdetachstate
(Attributes'Access, PTHREAD_CREATE_DETACHED);
pragma Assert (Result = 0);
Result := pthread_attr_setstacksize
(Attributes'Access, Adjusted_Stack_Size);
pragma Assert (Result = 0);
-- This call may be unnecessary, not sure. ???
Result := pthread_attr_setinheritsched
(Attributes'Access, PTHREAD_EXPLICIT_SCHED);
pragma Assert (Result = 0);
Result := pthread_create
(T.Common.LL.Thread'Access,
Attributes'Access,
Thread_Body_Access (Wrapper),
To_Address (T));
-- ENOMEM is a valid run-time error. Don't shut down.
pragma Assert (Result = 0
or else Result = EAGAIN or else Result = ENOMEM);
Succeeded := Result = 0;
Result := pthread_attr_destroy (Attributes'Access);
pragma Assert (Result = 0);
if Succeeded then
Set_Priority (T, Priority);
end if;
end Create_Task;
------------------
-- Finalize_TCB --
------------------
procedure Finalize_TCB (T : Task_ID) is
Result : Interfaces.C.int;
Tmp : Task_ID := T;
procedure Free is new
Unchecked_Deallocation (Ada_Task_Control_Block, Task_ID);
procedure Free is new Unchecked_Deallocation
(Exc_Stack_T, Exc_Stack_Ptr_T);
begin
Result := pthread_mutex_destroy (T.Common.LL.L'Access);
pragma Assert (Result = 0);
Result := pthread_cond_destroy (T.Common.LL.CV'Access);
pragma Assert (Result = 0);
if T.Known_Tasks_Index /= -1 then
Known_Tasks (T.Known_Tasks_Index) := null;
end if;
Free (T.Common.LL.Exc_Stack_Ptr);
Free (Tmp);
end Finalize_TCB;
---------------
-- Exit_Task --
---------------
procedure Exit_Task is
begin
pthread_exit (System.Null_Address);
end Exit_Task;
----------------
-- Abort_Task --
----------------
procedure Abort_Task (T : Task_ID) is
begin
-- Why is this commented out ???
-- if T = Self and then T.Deferral_Level = 0
-- and then T.Pending_ATC_Level < T.ATC_Nesting_Level
-- then
-- raise Standard'Abort_Signal;
-- end if;
--
-- Interrupt Server_Tasks may be waiting on an event flag
--
if T.Common.State = Interrupt_Server_Blocked_On_Event_Flag then
Wakeup (T, Interrupt_Server_Blocked_On_Event_Flag);
end if;
end Abort_Task;
----------------
-- Check_Exit --
----------------
-- Dummy versions. The only currently working versions is for solaris
-- (native).
function Check_Exit (Self_ID : ST.Task_ID) return Boolean is
begin
return True;
end Check_Exit;
--------------------
-- Check_No_Locks --
--------------------
function Check_No_Locks (Self_ID : ST.Task_ID) return Boolean is
begin
return True;
end Check_No_Locks;
----------------------
-- Environment_Task --
----------------------
function Environment_Task return Task_ID is
begin
return Environment_Task_ID;
end Environment_Task;
-------------------------
-- Lock_All_Tasks_List --
-------------------------
procedure Lock_All_Tasks_List is
begin
Write_Lock (All_Tasks_L'Access);
end Lock_All_Tasks_List;
---------------------------
-- Unlock_All_Tasks_List --
---------------------------
procedure Unlock_All_Tasks_List is
begin
Unlock (All_Tasks_L'Access);
end Unlock_All_Tasks_List;
------------------
-- Suspend_Task --
------------------
function Suspend_Task
(T : ST.Task_ID;
Thread_Self : Thread_Id) return Boolean is
begin
return False;
end Suspend_Task;
-----------------
-- Resume_Task --
-----------------
function Resume_Task
(T : ST.Task_ID;
Thread_Self : Thread_Id) return Boolean is
begin
return False;
end Resume_Task;
----------------
-- Initialize --
----------------
procedure Initialize (Environment_Task : Task_ID) is
begin
Environment_Task_ID := Environment_Task;
Initialize_Lock (All_Tasks_L'Access, All_Tasks_Level);
-- Initialize the lock used to synchronize chain of all ATCBs.
Enter_Task (Environment_Task);
end Initialize;
begin
declare
Result : Interfaces.C.int;
begin
Result := pthread_key_create (ATCB_Key'Access, null);
pragma Assert (Result = 0);
end;
end System.Task_Primitives.Operations;