1 ------------------------------------------------------------------------------
3 -- GNAT RUN-TIME LIBRARY (GNARL) COMPONENTS --
5 -- 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 --
9 -- Copyright (C) 1992-2008, 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, 51 Franklin Street, Fifth Floor, --
20 -- Boston, MA 02110-1301, 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 a NT (native) version of this package
36 -- This package contains all the GNULL primitives that interface directly with
40 -- Turn off polling, we do not want ATC polling to take place during tasking
41 -- operations. It causes infinite loops and other problems.
43 with Ada.Unchecked_Deallocation;
46 with Interfaces.C.Strings;
48 with System.Tasking.Debug;
49 with System.OS_Primitives;
50 with System.Task_Info;
51 with System.Interrupt_Management;
52 with System.Win32.Ext;
54 with System.Soft_Links;
55 -- We use System.Soft_Links instead of System.Tasking.Initialization because
56 -- the later is a higher level package that we shouldn't depend on. For
57 -- example when using the restricted run time, it is replaced by
58 -- System.Tasking.Restricted.Stages.
60 package body System.Task_Primitives.Operations is
62 package SSL renames System.Soft_Links;
64 use System.Tasking.Debug;
67 use Interfaces.C.Strings;
68 use System.OS_Interface;
69 use System.Parameters;
70 use System.OS_Primitives;
75 pragma Link_With ("-Xlinker --stack=0x200000,0x1000");
76 -- Change the default stack size (2 MB) for tasking programs on Windows.
77 -- This allows about 1000 tasks running at the same time. Note that
78 -- we set the stack size for non tasking programs on System unit.
79 -- Also note that under Windows XP, we use a Windows XP extension to
80 -- specify the stack size on a per task basis, as done under other OSes.
86 procedure InitializeCriticalSection (pCriticalSection : access RTS_Lock);
87 procedure InitializeCriticalSection
88 (pCriticalSection : access CRITICAL_SECTION);
90 (Stdcall, InitializeCriticalSection, "InitializeCriticalSection");
92 procedure EnterCriticalSection (pCriticalSection : access RTS_Lock);
93 procedure EnterCriticalSection
94 (pCriticalSection : access CRITICAL_SECTION);
95 pragma Import (Stdcall, EnterCriticalSection, "EnterCriticalSection");
97 procedure LeaveCriticalSection (pCriticalSection : access RTS_Lock);
98 procedure LeaveCriticalSection (pCriticalSection : access CRITICAL_SECTION);
99 pragma Import (Stdcall, LeaveCriticalSection, "LeaveCriticalSection");
101 procedure DeleteCriticalSection (pCriticalSection : access RTS_Lock);
102 procedure DeleteCriticalSection
103 (pCriticalSection : access CRITICAL_SECTION);
104 pragma Import (Stdcall, DeleteCriticalSection, "DeleteCriticalSection");
110 Environment_Task_Id : Task_Id;
111 -- A variable to hold Task_Id for the environment task
113 Single_RTS_Lock : aliased RTS_Lock;
114 -- This is a lock to allow only one thread of control in the RTS at
115 -- a time; it is used to execute in mutual exclusion from all other tasks.
116 -- Used mainly in Single_Lock mode, but also to protect All_Tasks_List
118 Time_Slice_Val : Integer;
119 pragma Import (C, Time_Slice_Val, "__gl_time_slice_val");
121 Dispatching_Policy : Character;
122 pragma Import (C, Dispatching_Policy, "__gl_task_dispatching_policy");
124 function Get_Policy (Prio : System.Any_Priority) return Character;
125 pragma Import (C, Get_Policy, "__gnat_get_specific_dispatching");
126 -- Get priority specific dispatching policy
128 Foreign_Task_Elaborated : aliased Boolean := True;
129 -- Used to identified fake tasks (i.e., non-Ada Threads)
131 Annex_D : Boolean := False;
132 -- Set to True if running with Annex-D semantics
134 ------------------------------------
135 -- The thread local storage index --
136 ------------------------------------
139 pragma Export (Ada, TlsIndex);
140 -- To ensure that this variable won't be local to this package, since
141 -- in some cases, inlining forces this variable to be global anyway.
149 function Is_Valid_Task return Boolean;
150 pragma Inline (Is_Valid_Task);
151 -- Does executing thread have a TCB?
153 procedure Set (Self_Id : Task_Id);
155 -- Set the self id for the current task
159 package body Specific is
161 function Is_Valid_Task return Boolean is
163 return TlsGetValue (TlsIndex) /= System.Null_Address;
166 procedure Set (Self_Id : Task_Id) is
169 Succeeded := TlsSetValue (TlsIndex, To_Address (Self_Id));
170 pragma Assert (Succeeded = Win32.TRUE);
175 ---------------------------------
176 -- Support for foreign threads --
177 ---------------------------------
179 function Register_Foreign_Thread (Thread : Thread_Id) return Task_Id;
180 -- Allocate and Initialize a new ATCB for the current Thread
182 function Register_Foreign_Thread
183 (Thread : Thread_Id) return Task_Id is separate;
185 ----------------------------------
186 -- Condition Variable Functions --
187 ----------------------------------
189 procedure Initialize_Cond (Cond : not null access Condition_Variable);
190 -- Initialize given condition variable Cond
192 procedure Finalize_Cond (Cond : not null access Condition_Variable);
193 -- Finalize given condition variable Cond
195 procedure Cond_Signal (Cond : not null access Condition_Variable);
196 -- Signal condition variable Cond
199 (Cond : not null access Condition_Variable;
200 L : not null access RTS_Lock);
201 -- Wait on conditional variable Cond, using lock L
203 procedure Cond_Timed_Wait
204 (Cond : not null access Condition_Variable;
205 L : not null access RTS_Lock;
207 Timed_Out : out Boolean;
208 Status : out Integer);
209 -- Do timed wait on condition variable Cond using lock L. The duration
210 -- of the timed wait is given by Rel_Time. When the condition is
211 -- signalled, Timed_Out shows whether or not a time out occurred.
212 -- Status is only valid if Timed_Out is False, in which case it
213 -- shows whether Cond_Timed_Wait completed successfully.
215 ---------------------
216 -- Initialize_Cond --
217 ---------------------
219 procedure Initialize_Cond (Cond : not null access Condition_Variable) is
222 hEvent := CreateEvent (null, Win32.TRUE, Win32.FALSE, Null_Ptr);
223 pragma Assert (hEvent /= 0);
224 Cond.all := Condition_Variable (hEvent);
231 -- No such problem here, DosCloseEventSem has been derived.
232 -- What does such refer to in above comment???
234 procedure Finalize_Cond (Cond : not null access Condition_Variable) is
237 Result := CloseHandle (HANDLE (Cond.all));
238 pragma Assert (Result = Win32.TRUE);
245 procedure Cond_Signal (Cond : not null access Condition_Variable) is
248 Result := SetEvent (HANDLE (Cond.all));
249 pragma Assert (Result = Win32.TRUE);
256 -- Pre-condition: Cond is posted
259 -- Post-condition: Cond is posted
263 (Cond : not null access Condition_Variable;
264 L : not null access RTS_Lock)
270 -- Must reset Cond BEFORE L is unlocked
272 Result_Bool := ResetEvent (HANDLE (Cond.all));
273 pragma Assert (Result_Bool = Win32.TRUE);
274 Unlock (L, Global_Lock => True);
276 -- No problem if we are interrupted here: if the condition is signaled,
277 -- WaitForSingleObject will simply not block
279 Result := WaitForSingleObject (HANDLE (Cond.all), Wait_Infinite);
280 pragma Assert (Result = 0);
282 Write_Lock (L, Global_Lock => True);
285 ---------------------
286 -- Cond_Timed_Wait --
287 ---------------------
289 -- Pre-condition: Cond is posted
292 -- Post-condition: Cond is posted
295 procedure Cond_Timed_Wait
296 (Cond : not null access Condition_Variable;
297 L : not null access RTS_Lock;
299 Timed_Out : out Boolean;
300 Status : out Integer)
302 Time_Out_Max : constant DWORD := 16#FFFF0000#;
303 -- NT 4 can't handle excessive timeout values (e.g. DWORD'Last - 1)
310 -- Must reset Cond BEFORE L is unlocked
312 Result := ResetEvent (HANDLE (Cond.all));
313 pragma Assert (Result = Win32.TRUE);
314 Unlock (L, Global_Lock => True);
316 -- No problem if we are interrupted here: if the condition is signaled,
317 -- WaitForSingleObject will simply not block
319 if Rel_Time <= 0.0 then
324 if Rel_Time >= Duration (Time_Out_Max) / 1000 then
325 Time_Out := Time_Out_Max;
327 Time_Out := DWORD (Rel_Time * 1000);
330 Wait_Result := WaitForSingleObject (HANDLE (Cond.all), Time_Out);
332 if Wait_Result = WAIT_TIMEOUT then
340 Write_Lock (L, Global_Lock => True);
342 -- Ensure post-condition
345 Result := SetEvent (HANDLE (Cond.all));
346 pragma Assert (Result = Win32.TRUE);
349 Status := Integer (Wait_Result);
356 -- The underlying thread system sets a guard page at the bottom of a thread
357 -- stack, so nothing is needed.
358 -- ??? Check the comment above
360 procedure Stack_Guard (T : ST.Task_Id; On : Boolean) is
361 pragma Unreferenced (T, On);
370 function Get_Thread_Id (T : ST.Task_Id) return OSI.Thread_Id is
372 return T.Common.LL.Thread;
379 function Self return Task_Id is
380 Self_Id : constant Task_Id := To_Task_Id (TlsGetValue (TlsIndex));
382 if Self_Id = null then
383 return Register_Foreign_Thread (GetCurrentThread);
389 ---------------------
390 -- Initialize_Lock --
391 ---------------------
393 -- Note: mutexes and cond_variables needed per-task basis are initialized
394 -- in Intialize_TCB and the Storage_Error is handled. Other mutexes (such
395 -- as RTS_Lock, Memory_Lock...) used in the RTS is initialized before any
396 -- status change of RTS. Therefore raising Storage_Error in the following
397 -- routines should be able to be handled safely.
399 procedure Initialize_Lock
400 (Prio : System.Any_Priority;
401 L : not null access Lock)
404 InitializeCriticalSection (L.Mutex'Access);
405 L.Owner_Priority := 0;
409 procedure Initialize_Lock
410 (L : not null access RTS_Lock; Level : Lock_Level)
412 pragma Unreferenced (Level);
414 InitializeCriticalSection (L);
421 procedure Finalize_Lock (L : not null access Lock) is
423 DeleteCriticalSection (L.Mutex'Access);
426 procedure Finalize_Lock (L : not null access RTS_Lock) is
428 DeleteCriticalSection (L);
436 (L : not null access Lock; Ceiling_Violation : out Boolean) is
438 L.Owner_Priority := Get_Priority (Self);
440 if L.Priority < L.Owner_Priority then
441 Ceiling_Violation := True;
445 EnterCriticalSection (L.Mutex'Access);
447 Ceiling_Violation := False;
451 (L : not null access RTS_Lock;
452 Global_Lock : Boolean := False)
455 if not Single_Lock or else Global_Lock then
456 EnterCriticalSection (L);
460 procedure Write_Lock (T : Task_Id) is
462 if not Single_Lock then
463 EnterCriticalSection (T.Common.LL.L'Access);
472 (L : not null access Lock; Ceiling_Violation : out Boolean) is
474 Write_Lock (L, Ceiling_Violation);
481 procedure Unlock (L : not null access Lock) is
483 LeaveCriticalSection (L.Mutex'Access);
487 (L : not null access RTS_Lock; Global_Lock : Boolean := False) is
489 if not Single_Lock or else Global_Lock then
490 LeaveCriticalSection (L);
494 procedure Unlock (T : Task_Id) is
496 if not Single_Lock then
497 LeaveCriticalSection (T.Common.LL.L'Access);
505 -- Dynamic priority ceilings are not supported by the underlying system
507 procedure Set_Ceiling
508 (L : not null access Lock;
509 Prio : System.Any_Priority)
511 pragma Unreferenced (L, Prio);
522 Reason : System.Tasking.Task_States)
524 pragma Unreferenced (Reason);
527 pragma Assert (Self_ID = Self);
530 Cond_Wait (Self_ID.Common.LL.CV'Access, Single_RTS_Lock'Access);
532 Cond_Wait (Self_ID.Common.LL.CV'Access, Self_ID.Common.LL.L'Access);
535 if Self_ID.Deferral_Level = 0
536 and then Self_ID.Pending_ATC_Level < Self_ID.ATC_Nesting_Level
539 raise Standard'Abort_Signal;
547 -- This is for use within the run-time system, so abort is assumed to be
548 -- already deferred, and the caller should be holding its own ATCB lock.
550 procedure Timed_Sleep
553 Mode : ST.Delay_Modes;
554 Reason : System.Tasking.Task_States;
555 Timedout : out Boolean;
556 Yielded : out Boolean)
558 pragma Unreferenced (Reason);
559 Check_Time : Duration := Monotonic_Clock;
564 pragma Unreferenced (Result);
566 Local_Timedout : Boolean;
572 if Mode = Relative then
574 Abs_Time := Duration'Min (Time, Max_Sensible_Delay) + Check_Time;
576 Rel_Time := Time - Check_Time;
580 if Rel_Time > 0.0 then
582 exit when Self_ID.Pending_ATC_Level < Self_ID.ATC_Nesting_Level;
586 (Self_ID.Common.LL.CV'Access,
587 Single_RTS_Lock'Access,
588 Rel_Time, Local_Timedout, Result);
591 (Self_ID.Common.LL.CV'Access,
592 Self_ID.Common.LL.L'Access,
593 Rel_Time, Local_Timedout, Result);
596 Check_Time := Monotonic_Clock;
597 exit when Abs_Time <= Check_Time;
599 if not Local_Timedout then
601 -- Somebody may have called Wakeup for us
607 Rel_Time := Abs_Time - Check_Time;
616 procedure Timed_Delay
619 Mode : ST.Delay_Modes)
621 Check_Time : Duration := Monotonic_Clock;
627 pragma Unreferenced (Timedout, Result);
634 Write_Lock (Self_ID);
636 if Mode = Relative then
638 Abs_Time := Time + Check_Time;
640 Rel_Time := Time - Check_Time;
644 if Rel_Time > 0.0 then
645 Self_ID.Common.State := Delay_Sleep;
648 exit when Self_ID.Pending_ATC_Level < Self_ID.ATC_Nesting_Level;
652 (Self_ID.Common.LL.CV'Access,
653 Single_RTS_Lock'Access,
654 Rel_Time, Timedout, Result);
657 (Self_ID.Common.LL.CV'Access,
658 Self_ID.Common.LL.L'Access,
659 Rel_Time, Timedout, Result);
662 Check_Time := Monotonic_Clock;
663 exit when Abs_Time <= Check_Time;
665 Rel_Time := Abs_Time - Check_Time;
668 Self_ID.Common.State := Runnable;
684 procedure Wakeup (T : Task_Id; Reason : System.Tasking.Task_States) is
685 pragma Unreferenced (Reason);
687 Cond_Signal (T.Common.LL.CV'Access);
694 procedure Yield (Do_Yield : Boolean := True) is
700 -- If running with Annex-D semantics we need a delay
701 -- above 0 milliseconds here otherwise processes give
702 -- enough time to the other tasks to have a chance to
705 -- This makes cxd8002 ACATS pass on Windows.
715 type Prio_Array_Type is array (System.Any_Priority) of Integer;
716 pragma Atomic_Components (Prio_Array_Type);
718 Prio_Array : Prio_Array_Type;
719 -- Global array containing the id of the currently running task for
722 -- Note: we assume that we are on a single processor with run-til-blocked
725 procedure Set_Priority
727 Prio : System.Any_Priority;
728 Loss_Of_Inheritance : Boolean := False)
731 Array_Item : Integer;
734 Res := SetThreadPriority
735 (T.Common.LL.Thread, Interfaces.C.int (Underlying_Priorities (Prio)));
736 pragma Assert (Res = Win32.TRUE);
738 if Dispatching_Policy = 'F' or else Get_Policy (Prio) = 'F' then
740 -- Annex D requirement [RM D.2.2 par. 9]:
741 -- If the task drops its priority due to the loss of inherited
742 -- priority, it is added at the head of the ready queue for its
743 -- new active priority.
745 if Loss_Of_Inheritance
746 and then Prio < T.Common.Current_Priority
748 Array_Item := Prio_Array (T.Common.Base_Priority) + 1;
749 Prio_Array (T.Common.Base_Priority) := Array_Item;
752 -- Let some processes a chance to arrive
756 -- Then wait for our turn to proceed
758 exit when Array_Item = Prio_Array (T.Common.Base_Priority)
759 or else Prio_Array (T.Common.Base_Priority) = 1;
762 Prio_Array (T.Common.Base_Priority) :=
763 Prio_Array (T.Common.Base_Priority) - 1;
767 T.Common.Current_Priority := Prio;
774 function Get_Priority (T : Task_Id) return System.Any_Priority is
776 return T.Common.Current_Priority;
783 -- There were two paths were we needed to call Enter_Task :
784 -- 1) from System.Task_Primitives.Operations.Initialize
785 -- 2) from System.Tasking.Stages.Task_Wrapper
787 -- The thread initialisation has to be done only for the first case
789 -- This is because the GetCurrentThread NT call does not return the real
790 -- thread handler but only a "pseudo" one. It is not possible to release
791 -- the thread handle and free the system ressources from this "pseudo"
792 -- handle. So we really want to keep the real thread handle set in
793 -- System.Task_Primitives.Operations.Create_Task during thread creation.
795 procedure Enter_Task (Self_ID : Task_Id) is
796 procedure Init_Float;
797 pragma Import (C, Init_Float, "__gnat_init_float");
798 -- Properly initializes the FPU for x86 systems
801 Specific.Set (Self_ID);
804 if Self_ID.Common.Task_Info /= null
806 Self_ID.Common.Task_Info.CPU >= CPU_Number (Number_Of_Processors)
808 raise Invalid_CPU_Number;
811 Self_ID.Common.LL.Thread_Id := GetCurrentThreadId;
815 for J in Known_Tasks'Range loop
816 if Known_Tasks (J) = null then
817 Known_Tasks (J) := Self_ID;
818 Self_ID.Known_Tasks_Index := J;
830 function New_ATCB (Entry_Num : Task_Entry_Index) return Task_Id is
832 return new Ada_Task_Control_Block (Entry_Num);
839 function Is_Valid_Task return Boolean renames Specific.Is_Valid_Task;
841 -----------------------------
842 -- Register_Foreign_Thread --
843 -----------------------------
845 function Register_Foreign_Thread return Task_Id is
847 if Is_Valid_Task then
850 return Register_Foreign_Thread (GetCurrentThread);
852 end Register_Foreign_Thread;
858 procedure Initialize_TCB (Self_ID : Task_Id; Succeeded : out Boolean) is
860 -- Initialize thread ID to 0, this is needed to detect threads that
861 -- are not yet activated.
863 Self_ID.Common.LL.Thread := 0;
865 Initialize_Cond (Self_ID.Common.LL.CV'Access);
867 if not Single_Lock then
868 Initialize_Lock (Self_ID.Common.LL.L'Access, ATCB_Level);
878 procedure Create_Task
880 Wrapper : System.Address;
881 Stack_Size : System.Parameters.Size_Type;
882 Priority : System.Any_Priority;
883 Succeeded : out Boolean)
885 Initial_Stack_Size : constant := 1024;
886 -- We set the initial stack size to 1024. On Windows version prior to XP
887 -- there is no way to fix a task stack size. Only the initial stack size
888 -- can be set, the operating system will raise the task stack size if
891 function Is_Windows_XP return Integer;
892 pragma Import (C, Is_Windows_XP, "__gnat_is_windows_xp");
893 -- Returns 1 if running on Windows XP
896 TaskId : aliased DWORD;
897 pTaskParameter : Win32.PVOID;
899 Entry_Point : PTHREAD_START_ROUTINE;
902 pTaskParameter := To_Address (T);
904 Entry_Point := To_PTHREAD_START_ROUTINE (Wrapper);
906 if Is_Windows_XP = 1 then
907 hTask := CreateThread
912 DWORD (Create_Suspended) or
913 DWORD (Stack_Size_Param_Is_A_Reservation),
914 TaskId'Unchecked_Access);
916 hTask := CreateThread
921 DWORD (Create_Suspended),
922 TaskId'Unchecked_Access);
925 -- Step 1: Create the thread in blocked mode
932 -- Step 2: set its TCB
934 T.Common.LL.Thread := hTask;
936 -- Step 3: set its priority (child has inherited priority from parent)
938 Set_Priority (T, Priority);
940 if Time_Slice_Val = 0
941 or else Dispatching_Policy = 'F'
942 or else Get_Policy (Priority) = 'F'
944 -- Here we need Annex D semantics so we disable the NT priority
945 -- boost. A priority boost is temporarily given by the system to a
946 -- thread when it is taken out of a wait state.
948 SetThreadPriorityBoost (hTask, DisablePriorityBoost => Win32.TRUE);
951 -- Step 4: Handle Task_Info
953 if T.Common.Task_Info /= null then
954 if T.Common.Task_Info.CPU /= Task_Info.Any_CPU then
955 Result := SetThreadIdealProcessor (hTask, T.Common.Task_Info.CPU);
956 pragma Assert (Result = 1);
960 -- Step 5: Now, start it for good:
962 Result := ResumeThread (hTask);
963 pragma Assert (Result = 1);
965 Succeeded := Result = 1;
972 procedure Finalize_TCB (T : Task_Id) is
973 Self_ID : Task_Id := T;
976 Is_Self : constant Boolean := T = Self;
978 procedure Free is new
979 Ada.Unchecked_Deallocation (Ada_Task_Control_Block, Task_Id);
982 if not Single_Lock then
983 Finalize_Lock (T.Common.LL.L'Access);
986 Finalize_Cond (T.Common.LL.CV'Access);
988 if T.Known_Tasks_Index /= -1 then
989 Known_Tasks (T.Known_Tasks_Index) := null;
992 if Self_ID.Common.LL.Thread /= 0 then
994 -- This task has been activated. Wait for the thread to terminate
995 -- then close it. this is needed to release system ressources.
997 Result := WaitForSingleObject (T.Common.LL.Thread, Wait_Infinite);
998 pragma Assert (Result /= WAIT_FAILED);
999 Succeeded := CloseHandle (T.Common.LL.Thread);
1000 pragma Assert (Succeeded = Win32.TRUE);
1006 Specific.Set (null);
1014 procedure Exit_Task is
1016 Specific.Set (null);
1023 procedure Abort_Task (T : Task_Id) is
1024 pragma Unreferenced (T);
1029 ----------------------
1030 -- Environment_Task --
1031 ----------------------
1033 function Environment_Task return Task_Id is
1035 return Environment_Task_Id;
1036 end Environment_Task;
1042 procedure Lock_RTS is
1044 Write_Lock (Single_RTS_Lock'Access, Global_Lock => True);
1051 procedure Unlock_RTS is
1053 Unlock (Single_RTS_Lock'Access, Global_Lock => True);
1060 procedure Initialize (Environment_Task : Task_Id) is
1062 pragma Unreferenced (Discard);
1065 Environment_Task_Id := Environment_Task;
1066 OS_Primitives.Initialize;
1067 Interrupt_Management.Initialize;
1069 if Time_Slice_Val = 0 or else Dispatching_Policy = 'F' then
1070 -- Here we need Annex D semantics, switch the current process to the
1071 -- Realtime_Priority_Class.
1073 Discard := OS_Interface.SetPriorityClass
1074 (GetCurrentProcess, Realtime_Priority_Class);
1079 TlsIndex := TlsAlloc;
1081 -- Initialize the lock used to synchronize chain of all ATCBs
1083 Initialize_Lock (Single_RTS_Lock'Access, RTS_Lock_Level);
1085 Environment_Task.Common.LL.Thread := GetCurrentThread;
1086 Enter_Task (Environment_Task);
1089 ---------------------
1090 -- Monotonic_Clock --
1091 ---------------------
1093 function Monotonic_Clock return Duration
1094 renames System.OS_Primitives.Monotonic_Clock;
1100 function RT_Resolution return Duration is
1102 return 0.000_001; -- 1 micro-second
1109 procedure Initialize (S : in out Suspension_Object) is
1111 -- Initialize internal state. It is always initialized to False (ARM
1117 -- Initialize internal mutex
1119 InitializeCriticalSection (S.L'Access);
1121 -- Initialize internal condition variable
1123 S.CV := CreateEvent (null, Win32.TRUE, Win32.FALSE, Null_Ptr);
1124 pragma Assert (S.CV /= 0);
1131 procedure Finalize (S : in out Suspension_Object) is
1134 -- Destroy internal mutex
1136 DeleteCriticalSection (S.L'Access);
1138 -- Destroy internal condition variable
1140 Result := CloseHandle (S.CV);
1141 pragma Assert (Result = Win32.TRUE);
1148 function Current_State (S : Suspension_Object) return Boolean is
1150 -- We do not want to use lock on this read operation. State is marked
1151 -- as Atomic so that we ensure that the value retrieved is correct.
1160 procedure Set_False (S : in out Suspension_Object) is
1162 SSL.Abort_Defer.all;
1164 EnterCriticalSection (S.L'Access);
1168 LeaveCriticalSection (S.L'Access);
1170 SSL.Abort_Undefer.all;
1177 procedure Set_True (S : in out Suspension_Object) is
1180 SSL.Abort_Defer.all;
1182 EnterCriticalSection (S.L'Access);
1184 -- If there is already a task waiting on this suspension object then
1185 -- we resume it, leaving the state of the suspension object to False,
1186 -- as it is specified in ARM D.10 par. 9. Otherwise, it just leaves
1187 -- the state to True.
1193 Result := SetEvent (S.CV);
1194 pragma Assert (Result = Win32.TRUE);
1199 LeaveCriticalSection (S.L'Access);
1201 SSL.Abort_Undefer.all;
1204 ------------------------
1205 -- Suspend_Until_True --
1206 ------------------------
1208 procedure Suspend_Until_True (S : in out Suspension_Object) is
1212 SSL.Abort_Defer.all;
1214 EnterCriticalSection (S.L'Access);
1217 -- Program_Error must be raised upon calling Suspend_Until_True
1218 -- if another task is already waiting on that suspension object
1219 -- (ARM D.10 par. 10).
1221 LeaveCriticalSection (S.L'Access);
1223 SSL.Abort_Undefer.all;
1225 raise Program_Error;
1227 -- Suspend the task if the state is False. Otherwise, the task
1228 -- continues its execution, and the state of the suspension object
1229 -- is set to False (ARM D.10 par. 9).
1234 LeaveCriticalSection (S.L'Access);
1236 SSL.Abort_Undefer.all;
1240 -- Must reset CV BEFORE L is unlocked
1242 Result_Bool := ResetEvent (S.CV);
1243 pragma Assert (Result_Bool = Win32.TRUE);
1245 LeaveCriticalSection (S.L'Access);
1247 SSL.Abort_Undefer.all;
1249 Result := WaitForSingleObject (S.CV, Wait_Infinite);
1250 pragma Assert (Result = 0);
1253 end Suspend_Until_True;
1259 -- Dummy versions. The only currently working versions is for solaris
1262 function Check_Exit (Self_ID : ST.Task_Id) return Boolean is
1263 pragma Unreferenced (Self_ID);
1268 --------------------
1269 -- Check_No_Locks --
1270 --------------------
1272 function Check_No_Locks (Self_ID : ST.Task_Id) return Boolean is
1273 pragma Unreferenced (Self_ID);
1282 function Suspend_Task
1284 Thread_Self : Thread_Id) return Boolean
1287 if T.Common.LL.Thread /= Thread_Self then
1288 return SuspendThread (T.Common.LL.Thread) = NO_ERROR;
1298 function Resume_Task
1300 Thread_Self : Thread_Id) return Boolean
1303 if T.Common.LL.Thread /= Thread_Self then
1304 return ResumeThread (T.Common.LL.Thread) = NO_ERROR;
1310 --------------------
1311 -- Stop_All_Tasks --
1312 --------------------
1314 procedure Stop_All_Tasks is
1323 function Stop_Task (T : ST.Task_Id) return Boolean is
1324 pragma Unreferenced (T);
1333 function Continue_Task (T : ST.Task_Id) return Boolean is
1334 pragma Unreferenced (T);
1339 end System.Task_Primitives.Operations;