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) 1992-2006, 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 OpenVMS/Alpha version of this package
36 -- This package contains all the GNULL primitives that interface directly
37 -- with the underlying OS.
40 -- Turn off polling, we do not want ATC polling to take place during
41 -- tasking operations. It causes infinite loops and other problems.
43 with System
.Tasking
.Debug
;
44 -- used for Known_Tasks
46 with System
.OS_Primitives
;
47 -- used for Delay_Modes
53 with System
.Soft_Links
;
54 -- used for Get_Exc_Stack_Addr
55 -- Abort_Defer/Undefer
57 with Unchecked_Conversion
;
58 with Unchecked_Deallocation
;
60 package body System
.Task_Primitives
.Operations
is
62 use System
.Tasking
.Debug
;
65 use System
.OS_Interface
;
66 use System
.Parameters
;
67 use System
.OS_Primitives
;
68 use type System
.OS_Primitives
.OS_Time
;
70 package SSL
renames System
.Soft_Links
;
76 -- The followings are logically constants, but need to be initialized
79 Single_RTS_Lock
: aliased RTS_Lock
;
80 -- This is a lock to allow only one thread of control in the RTS at
81 -- a time; it is used to execute in mutual exclusion from all other tasks.
82 -- Used mainly in Single_Lock mode, but also to protect All_Tasks_List
84 ATCB_Key
: aliased pthread_key_t
;
85 -- Key used to find the Ada Task_Id associated with a thread
87 Environment_Task_Id
: Task_Id
;
88 -- A variable to hold Task_Id for the environment task.
90 Time_Slice_Val
: Integer;
91 pragma Import
(C
, Time_Slice_Val
, "__gl_time_slice_val");
93 Dispatching_Policy
: Character;
94 pragma Import
(C
, Dispatching_Policy
, "__gl_task_dispatching_policy");
96 Foreign_Task_Elaborated
: aliased Boolean := True;
97 -- Used to identified fake tasks (i.e., non-Ada Threads).
105 procedure Initialize
(Environment_Task
: Task_Id
);
106 pragma Inline
(Initialize
);
107 -- Initialize various data needed by this package.
109 function Is_Valid_Task
return Boolean;
110 pragma Inline
(Is_Valid_Task
);
111 -- Does executing thread have a TCB?
113 procedure Set
(Self_Id
: Task_Id
);
115 -- Set the self id for the current task
117 function Self
return Task_Id
;
118 pragma Inline
(Self
);
119 -- Return a pointer to the Ada Task Control Block of the calling task
123 package body Specific
is separate;
124 -- The body of this package is target specific.
126 ---------------------------------
127 -- Support for foreign threads --
128 ---------------------------------
130 function Register_Foreign_Thread
(Thread
: Thread_Id
) return Task_Id
;
131 -- Allocate and Initialize a new ATCB for the current Thread
133 function Register_Foreign_Thread
134 (Thread
: Thread_Id
) return Task_Id
is separate;
136 -----------------------
137 -- Local Subprograms --
138 -----------------------
140 function To_Task_Id
is new Unchecked_Conversion
(System
.Address
, Task_Id
);
142 function To_Address
is new Unchecked_Conversion
(Task_Id
, System
.Address
);
144 function Get_Exc_Stack_Addr
return Address
;
145 -- Replace System.Soft_Links.Get_Exc_Stack_Addr_NT
147 procedure Timer_Sleep_AST
(ID
: Address
);
148 -- Signal the condition variable when AST fires.
150 procedure Timer_Sleep_AST
(ID
: Address
) is
151 Result
: Interfaces
.C
.int
;
152 Self_ID
: constant Task_Id
:= To_Task_Id
(ID
);
154 Self_ID
.Common
.LL
.AST_Pending
:= False;
155 Result
:= pthread_cond_signal_int_np
(Self_ID
.Common
.LL
.CV
'Access);
156 pragma Assert
(Result
= 0);
163 -- The underlying thread system sets a guard page at the
164 -- bottom of a thread stack, so nothing is needed.
165 -- ??? Check the comment above
167 procedure Stack_Guard
(T
: ST
.Task_Id
; On
: Boolean) is
168 pragma Unreferenced
(T
);
169 pragma Unreferenced
(On
);
178 function Get_Thread_Id
(T
: ST
.Task_Id
) return OSI
.Thread_Id
is
180 return T
.Common
.LL
.Thread
;
187 function Self
return Task_Id
renames Specific
.Self
;
189 ---------------------
190 -- Initialize_Lock --
191 ---------------------
193 -- Note: mutexes and cond_variables needed per-task basis are
194 -- initialized in Initialize_TCB and the Storage_Error is
195 -- handled. Other mutexes (such as RTS_Lock, Memory_Lock...)
196 -- used in RTS is initialized before any status change of RTS.
197 -- Therefore rasing Storage_Error in the following routines
198 -- should be able to be handled safely.
200 procedure Initialize_Lock
(Prio
: System
.Any_Priority
; L
: access Lock
) is
201 Attributes
: aliased pthread_mutexattr_t
;
202 Result
: Interfaces
.C
.int
;
205 Result
:= pthread_mutexattr_init
(Attributes
'Access);
206 pragma Assert
(Result
= 0 or else Result
= ENOMEM
);
208 if Result
= ENOMEM
then
213 L
.Prio
:= Interfaces
.C
.int
(Prio
);
215 Result
:= pthread_mutex_init
(L
.L
'Access, Attributes
'Access);
216 pragma Assert
(Result
= 0 or else Result
= ENOMEM
);
218 if Result
= ENOMEM
then
222 Result
:= pthread_mutexattr_destroy
(Attributes
'Access);
223 pragma Assert
(Result
= 0);
226 procedure Initialize_Lock
(L
: access RTS_Lock
; Level
: Lock_Level
) is
227 pragma Unreferenced
(Level
);
229 Attributes
: aliased pthread_mutexattr_t
;
230 Result
: Interfaces
.C
.int
;
233 Result
:= pthread_mutexattr_init
(Attributes
'Access);
234 pragma Assert
(Result
= 0 or else Result
= ENOMEM
);
236 if Result
= ENOMEM
then
240 -- Don't use, see comment in s-osinte.ads about ERRORCHECK mutexes???
241 -- Result := pthread_mutexattr_settype_np
242 -- (Attributes'Access, PTHREAD_MUTEX_ERRORCHECK_NP);
243 -- pragma Assert (Result = 0);
245 -- Result := pthread_mutexattr_setprotocol
246 -- (Attributes'Access, PTHREAD_PRIO_PROTECT);
247 -- pragma Assert (Result = 0);
249 -- Result := pthread_mutexattr_setprioceiling
250 -- (Attributes'Access, Interfaces.C.int (System.Any_Priority'Last));
251 -- pragma Assert (Result = 0);
253 Result
:= pthread_mutex_init
(L
, Attributes
'Access);
255 pragma Assert
(Result
= 0 or else Result
= ENOMEM
);
257 if Result
= ENOMEM
then
261 Result
:= pthread_mutexattr_destroy
(Attributes
'Access);
262 pragma Assert
(Result
= 0);
269 procedure Finalize_Lock
(L
: access Lock
) is
270 Result
: Interfaces
.C
.int
;
272 Result
:= pthread_mutex_destroy
(L
.L
'Access);
273 pragma Assert
(Result
= 0);
276 procedure Finalize_Lock
(L
: access RTS_Lock
) is
277 Result
: Interfaces
.C
.int
;
279 Result
:= pthread_mutex_destroy
(L
);
280 pragma Assert
(Result
= 0);
287 procedure Write_Lock
(L
: access Lock
; Ceiling_Violation
: out Boolean) is
288 Self_ID
: constant Task_Id
:= Self
;
289 All_Tasks_Link
: constant Task_Id
:= Self
.Common
.All_Tasks_Link
;
290 Current_Prio
: System
.Any_Priority
;
291 Result
: Interfaces
.C
.int
;
294 Current_Prio
:= Get_Priority
(Self_ID
);
296 -- If there is no other tasks, no need to check priorities
298 if All_Tasks_Link
/= Null_Task
299 and then L
.Prio
< Interfaces
.C
.int
(Current_Prio
)
301 Ceiling_Violation
:= True;
305 Result
:= pthread_mutex_lock
(L
.L
'Access);
306 pragma Assert
(Result
= 0);
308 Ceiling_Violation
:= False;
309 -- Why is this commented out ???
310 -- L.Prio_Save := Interfaces.C.int (Current_Prio);
311 -- Set_Priority (Self_ID, System.Any_Priority (L.Prio));
315 (L
: access RTS_Lock
;
316 Global_Lock
: Boolean := False)
318 Result
: Interfaces
.C
.int
;
320 if not Single_Lock
or else Global_Lock
then
321 Result
:= pthread_mutex_lock
(L
);
322 pragma Assert
(Result
= 0);
326 procedure Write_Lock
(T
: Task_Id
) is
327 Result
: Interfaces
.C
.int
;
329 if not Single_Lock
then
330 Result
:= pthread_mutex_lock
(T
.Common
.LL
.L
'Access);
331 pragma Assert
(Result
= 0);
339 procedure Read_Lock
(L
: access Lock
; Ceiling_Violation
: out Boolean) is
341 Write_Lock
(L
, Ceiling_Violation
);
348 procedure Unlock
(L
: access Lock
) is
349 Result
: Interfaces
.C
.int
;
351 Result
:= pthread_mutex_unlock
(L
.L
'Access);
352 pragma Assert
(Result
= 0);
355 procedure Unlock
(L
: access RTS_Lock
; Global_Lock
: Boolean := False) is
356 Result
: Interfaces
.C
.int
;
358 if not Single_Lock
or else Global_Lock
then
359 Result
:= pthread_mutex_unlock
(L
);
360 pragma Assert
(Result
= 0);
364 procedure Unlock
(T
: Task_Id
) is
365 Result
: Interfaces
.C
.int
;
367 if not Single_Lock
then
368 Result
:= pthread_mutex_unlock
(T
.Common
.LL
.L
'Access);
369 pragma Assert
(Result
= 0);
379 Reason
: System
.Tasking
.Task_States
)
381 pragma Unreferenced
(Reason
);
382 Result
: Interfaces
.C
.int
;
386 Result
:= pthread_cond_wait
387 (Self_ID
.Common
.LL
.CV
'Access, Single_RTS_Lock
'Access);
389 Result
:= pthread_cond_wait
390 (Self_ID
.Common
.LL
.CV
'Access, Self_ID
.Common
.LL
.L
'Access);
393 -- EINTR is not considered a failure
395 pragma Assert
(Result
= 0 or else Result
= EINTR
);
397 if Self_ID
.Deferral_Level
= 0
398 and then Self_ID
.Pending_ATC_Level
< Self_ID
.ATC_Nesting_Level
401 raise Standard
'Abort_Signal;
409 procedure Timed_Sleep
412 Mode
: ST
.Delay_Modes
;
413 Reason
: System
.Tasking
.Task_States
;
414 Timedout
: out Boolean;
415 Yielded
: out Boolean)
417 pragma Unreferenced
(Reason
);
419 Sleep_Time
: OS_Time
;
420 Result
: Interfaces
.C
.int
;
421 Status
: Cond_Value_Type
;
423 -- The body below requires more comments ???
429 Sleep_Time
:= To_OS_Time
(Time
, Mode
);
431 if Self_ID
.Pending_ATC_Level
< Self_ID
.ATC_Nesting_Level
432 or else Self_ID
.Pending_Priority_Change
437 Self_ID
.Common
.LL
.AST_Pending
:= True;
440 (Status
, 0, Sleep_Time
,
441 Timer_Sleep_AST
'Access, To_Address
(Self_ID
), 0);
443 if (Status
and 1) /= 1 then
448 Result
:= pthread_cond_wait
449 (Self_ID
.Common
.LL
.CV
'Access, Single_RTS_Lock
'Access);
450 pragma Assert
(Result
= 0);
453 Result
:= pthread_cond_wait
454 (Self_ID
.Common
.LL
.CV
'Access, Self_ID
.Common
.LL
.L
'Access);
455 pragma Assert
(Result
= 0);
460 if not Self_ID
.Common
.LL
.AST_Pending
then
463 Sys_Cantim
(Status
, To_Address
(Self_ID
), 0);
464 pragma Assert
((Status
and 1) = 1);
472 procedure Timed_Delay
475 Mode
: ST
.Delay_Modes
)
477 Sleep_Time
: OS_Time
;
478 Result
: Interfaces
.C
.int
;
479 Status
: Cond_Value_Type
;
480 Yielded
: Boolean := False;
487 -- More comments required in body below ???
489 Write_Lock
(Self_ID
);
491 if Time
/= 0.0 or else Mode
/= Relative
then
492 Sleep_Time
:= To_OS_Time
(Time
, Mode
);
494 if Mode
= Relative
or else OS_Clock
< Sleep_Time
then
495 Self_ID
.Common
.State
:= Delay_Sleep
;
496 Self_ID
.Common
.LL
.AST_Pending
:= True;
499 (Status
, 0, Sleep_Time
,
500 Timer_Sleep_AST
'Access, To_Address
(Self_ID
), 0);
502 if (Status
and 1) /= 1 then
507 if Self_ID
.Pending_Priority_Change
then
508 Self_ID
.Pending_Priority_Change
:= False;
509 Self_ID
.Common
.Base_Priority
:= Self_ID
.New_Base_Priority
;
510 Set_Priority
(Self_ID
, Self_ID
.Common
.Base_Priority
);
513 if Self_ID
.Pending_ATC_Level
< Self_ID
.ATC_Nesting_Level
then
514 Sys_Cantim
(Status
, To_Address
(Self_ID
), 0);
515 pragma Assert
((Status
and 1) = 1);
520 Result
:= pthread_cond_wait
521 (Self_ID
.Common
.LL
.CV
'Access, Single_RTS_Lock
'Access);
522 pragma Assert
(Result
= 0);
524 Result
:= pthread_cond_wait
525 (Self_ID
.Common
.LL
.CV
'Access, Self_ID
.Common
.LL
.L
'Access);
526 pragma Assert
(Result
= 0);
531 exit when not Self_ID
.Common
.LL
.AST_Pending
;
534 Self_ID
.Common
.State
:= Runnable
;
545 Result
:= sched_yield
;
546 pragma Assert
(Result
= 0);
550 ---------------------
551 -- Monotonic_Clock --
552 ---------------------
554 function Monotonic_Clock
return Duration
555 renames System
.OS_Primitives
.Monotonic_Clock
;
561 function RT_Resolution
return Duration is
570 procedure Wakeup
(T
: Task_Id
; Reason
: System
.Tasking
.Task_States
) is
571 pragma Unreferenced
(Reason
);
572 Result
: Interfaces
.C
.int
;
574 Result
:= pthread_cond_signal
(T
.Common
.LL
.CV
'Access);
575 pragma Assert
(Result
= 0);
582 procedure Yield
(Do_Yield
: Boolean := True) is
583 Result
: Interfaces
.C
.int
;
584 pragma Unreferenced
(Result
);
587 Result
:= sched_yield
;
595 procedure Set_Priority
597 Prio
: System
.Any_Priority
;
598 Loss_Of_Inheritance
: Boolean := False)
600 pragma Unreferenced
(Loss_Of_Inheritance
);
602 Result
: Interfaces
.C
.int
;
603 Param
: aliased struct_sched_param
;
606 T
.Common
.Current_Priority
:= Prio
;
607 Param
.sched_priority
:= Interfaces
.C
.int
(Underlying_Priorities
(Prio
));
609 if Time_Slice_Val
> 0 then
610 Result
:= pthread_setschedparam
611 (T
.Common
.LL
.Thread
, SCHED_RR
, Param
'Access);
613 elsif Dispatching_Policy
= 'F' or else Time_Slice_Val
= 0 then
614 Result
:= pthread_setschedparam
615 (T
.Common
.LL
.Thread
, SCHED_FIFO
, Param
'Access);
618 -- SCHED_OTHER priorities are restricted to the range 8 - 15.
619 -- Since the translation from Underlying priorities results
620 -- in a range of 16 - 31, dividing by 2 gives the correct result.
622 Param
.sched_priority
:= Param
.sched_priority
/ 2;
623 Result
:= pthread_setschedparam
624 (T
.Common
.LL
.Thread
, SCHED_OTHER
, Param
'Access);
627 pragma Assert
(Result
= 0);
634 function Get_Priority
(T
: Task_Id
) return System
.Any_Priority
is
636 return T
.Common
.Current_Priority
;
643 procedure Enter_Task
(Self_ID
: Task_Id
) is
645 Self_ID
.Common
.LL
.Thread
:= pthread_self
;
647 Specific
.Set
(Self_ID
);
651 for J
in Known_Tasks
'Range loop
652 if Known_Tasks
(J
) = null then
653 Known_Tasks
(J
) := Self_ID
;
654 Self_ID
.Known_Tasks_Index
:= J
;
666 function New_ATCB
(Entry_Num
: Task_Entry_Index
) return Task_Id
is
668 return new Ada_Task_Control_Block
(Entry_Num
);
675 function Is_Valid_Task
return Boolean renames Specific
.Is_Valid_Task
;
677 -----------------------------
678 -- Register_Foreign_Thread --
679 -----------------------------
681 function Register_Foreign_Thread
return Task_Id
is
683 if Is_Valid_Task
then
686 return Register_Foreign_Thread
(pthread_self
);
688 end Register_Foreign_Thread
;
694 procedure Initialize_TCB
(Self_ID
: Task_Id
; Succeeded
: out Boolean) is
695 Mutex_Attr
: aliased pthread_mutexattr_t
;
696 Result
: Interfaces
.C
.int
;
697 Cond_Attr
: aliased pthread_condattr_t
;
700 -- More comments required in body below ???
702 if not Single_Lock
then
703 Result
:= pthread_mutexattr_init
(Mutex_Attr
'Access);
704 pragma Assert
(Result
= 0 or else Result
= ENOMEM
);
707 Result
:= pthread_mutex_init
(Self_ID
.Common
.LL
.L
'Access,
709 pragma Assert
(Result
= 0 or else Result
= ENOMEM
);
717 Result
:= pthread_mutexattr_destroy
(Mutex_Attr
'Access);
718 pragma Assert
(Result
= 0);
721 Result
:= pthread_condattr_init
(Cond_Attr
'Access);
722 pragma Assert
(Result
= 0 or else Result
= ENOMEM
);
725 Result
:= pthread_cond_init
(Self_ID
.Common
.LL
.CV
'Access,
727 pragma Assert
(Result
= 0 or else Result
= ENOMEM
);
732 Self_ID
.Common
.LL
.Exc_Stack_Ptr
:= new Exc_Stack_T
;
735 if not Single_Lock
then
736 Result
:= pthread_mutex_destroy
(Self_ID
.Common
.LL
.L
'Access);
737 pragma Assert
(Result
= 0);
743 Result
:= pthread_condattr_destroy
(Cond_Attr
'Access);
744 pragma Assert
(Result
= 0);
747 ------------------------
748 -- Get_Exc_Stack_Addr --
749 ------------------------
751 function Get_Exc_Stack_Addr
return Address
is
753 return Self
.Common
.LL
.Exc_Stack_Ptr
(Exc_Stack_T
'Last)'Address;
754 end Get_Exc_Stack_Addr
;
760 procedure Create_Task
762 Wrapper
: System
.Address
;
763 Stack_Size
: System
.Parameters
.Size_Type
;
764 Priority
: System
.Any_Priority
;
765 Succeeded
: out Boolean)
767 Attributes
: aliased pthread_attr_t
;
768 Result
: Interfaces
.C
.int
;
770 function Thread_Body_Access
is new
771 Unchecked_Conversion
(System
.Address
, Thread_Body
);
774 -- Since the initial signal mask of a thread is inherited from the
775 -- creator, we need to set our local signal mask mask all signals
776 -- during the creation operation, to make sure the new thread is
777 -- not disturbed by signals before it has set its own Task_Id.
779 Result
:= pthread_attr_init
(Attributes
'Access);
780 pragma Assert
(Result
= 0 or else Result
= ENOMEM
);
787 Result
:= pthread_attr_setdetachstate
788 (Attributes
'Access, PTHREAD_CREATE_DETACHED
);
789 pragma Assert
(Result
= 0);
791 Result
:= pthread_attr_setstacksize
792 (Attributes
'Access, Interfaces
.C
.size_t
(Stack_Size
));
793 pragma Assert
(Result
= 0);
795 -- This call may be unnecessary, not sure. ???
798 pthread_attr_setinheritsched
799 (Attributes
'Access, PTHREAD_EXPLICIT_SCHED
);
800 pragma Assert
(Result
= 0);
802 Result
:= pthread_create
803 (T
.Common
.LL
.Thread
'Access,
805 Thread_Body_Access
(Wrapper
),
808 -- ENOMEM is a valid run-time error. Don't shut down.
810 pragma Assert
(Result
= 0
811 or else Result
= EAGAIN
or else Result
= ENOMEM
);
813 Succeeded
:= Result
= 0;
815 Result
:= pthread_attr_destroy
(Attributes
'Access);
816 pragma Assert
(Result
= 0);
819 Set_Priority
(T
, Priority
);
827 procedure Finalize_TCB
(T
: Task_Id
) is
828 Result
: Interfaces
.C
.int
;
830 Is_Self
: constant Boolean := T
= Self
;
832 procedure Free
is new
833 Unchecked_Deallocation
(Ada_Task_Control_Block
, Task_Id
);
835 procedure Free
is new Unchecked_Deallocation
836 (Exc_Stack_T
, Exc_Stack_Ptr_T
);
839 if not Single_Lock
then
840 Result
:= pthread_mutex_destroy
(T
.Common
.LL
.L
'Access);
841 pragma Assert
(Result
= 0);
844 Result
:= pthread_cond_destroy
(T
.Common
.LL
.CV
'Access);
845 pragma Assert
(Result
= 0);
847 if T
.Known_Tasks_Index
/= -1 then
848 Known_Tasks
(T
.Known_Tasks_Index
) := null;
851 Free
(T
.Common
.LL
.Exc_Stack_Ptr
);
864 procedure Exit_Task
is
873 procedure Abort_Task
(T
: Task_Id
) is
875 -- Interrupt Server_Tasks may be waiting on an event flag
877 if T
.Common
.State
= Interrupt_Server_Blocked_On_Event_Flag
then
878 Wakeup
(T
, Interrupt_Server_Blocked_On_Event_Flag
);
886 procedure Initialize
(S
: in out Suspension_Object
) is
887 Mutex_Attr
: aliased pthread_mutexattr_t
;
888 Cond_Attr
: aliased pthread_condattr_t
;
889 Result
: Interfaces
.C
.int
;
891 -- Initialize internal state. It is always initialized to False (ARM
897 -- Initialize internal mutex
899 Result
:= pthread_mutexattr_init
(Mutex_Attr
'Access);
900 pragma Assert
(Result
= 0 or else Result
= ENOMEM
);
902 if Result
= ENOMEM
then
906 Result
:= pthread_mutex_init
(S
.L
'Access, Mutex_Attr
'Access);
907 pragma Assert
(Result
= 0 or else Result
= ENOMEM
);
909 if Result
= ENOMEM
then
910 Result
:= pthread_mutexattr_destroy
(Mutex_Attr
'Access);
911 pragma Assert
(Result
= 0);
916 Result
:= pthread_mutexattr_destroy
(Mutex_Attr
'Access);
917 pragma Assert
(Result
= 0);
919 -- Initialize internal condition variable
921 Result
:= pthread_condattr_init
(Cond_Attr
'Access);
922 pragma Assert
(Result
= 0 or else Result
= ENOMEM
);
925 Result
:= pthread_mutex_destroy
(S
.L
'Access);
926 pragma Assert
(Result
= 0);
928 if Result
= ENOMEM
then
933 Result
:= pthread_cond_init
(S
.CV
'Access, Cond_Attr
'Access);
934 pragma Assert
(Result
= 0 or else Result
= ENOMEM
);
937 Result
:= pthread_mutex_destroy
(S
.L
'Access);
938 pragma Assert
(Result
= 0);
940 if Result
= ENOMEM
then
941 Result
:= pthread_condattr_destroy
(Cond_Attr
'Access);
942 pragma Assert
(Result
= 0);
948 Result
:= pthread_condattr_destroy
(Cond_Attr
'Access);
949 pragma Assert
(Result
= 0);
956 procedure Finalize
(S
: in out Suspension_Object
) is
957 Result
: Interfaces
.C
.int
;
959 -- Destroy internal mutex
961 Result
:= pthread_mutex_destroy
(S
.L
'Access);
962 pragma Assert
(Result
= 0);
964 -- Destroy internal condition variable
966 Result
:= pthread_cond_destroy
(S
.CV
'Access);
967 pragma Assert
(Result
= 0);
974 function Current_State
(S
: Suspension_Object
) return Boolean is
976 -- We do not want to use lock on this read operation. State is marked
977 -- as Atomic so that we ensure that the value retrieved is correct.
986 procedure Set_False
(S
: in out Suspension_Object
) is
987 Result
: Interfaces
.C
.int
;
991 Result
:= pthread_mutex_lock
(S
.L
'Access);
992 pragma Assert
(Result
= 0);
996 Result
:= pthread_mutex_unlock
(S
.L
'Access);
997 pragma Assert
(Result
= 0);
999 SSL
.Abort_Undefer
.all;
1006 procedure Set_True
(S
: in out Suspension_Object
) is
1007 Result
: Interfaces
.C
.int
;
1009 SSL
.Abort_Defer
.all;
1011 Result
:= pthread_mutex_lock
(S
.L
'Access);
1012 pragma Assert
(Result
= 0);
1014 -- If there is already a task waiting on this suspension object then
1015 -- we resume it, leaving the state of the suspension object to False,
1016 -- as it is specified in ARM D.10 par. 9. Otherwise, it just leaves
1017 -- the state to True.
1023 Result
:= pthread_cond_signal
(S
.CV
'Access);
1024 pragma Assert
(Result
= 0);
1029 Result
:= pthread_mutex_unlock
(S
.L
'Access);
1030 pragma Assert
(Result
= 0);
1032 SSL
.Abort_Undefer
.all;
1035 ------------------------
1036 -- Suspend_Until_True --
1037 ------------------------
1039 procedure Suspend_Until_True
(S
: in out Suspension_Object
) is
1040 Result
: Interfaces
.C
.int
;
1042 SSL
.Abort_Defer
.all;
1044 Result
:= pthread_mutex_lock
(S
.L
'Access);
1045 pragma Assert
(Result
= 0);
1048 -- Program_Error must be raised upon calling Suspend_Until_True
1049 -- if another task is already waiting on that suspension object
1050 -- (ARM D.10 par. 10).
1052 Result
:= pthread_mutex_unlock
(S
.L
'Access);
1053 pragma Assert
(Result
= 0);
1055 SSL
.Abort_Undefer
.all;
1057 raise Program_Error
;
1059 -- Suspend the task if the state is False. Otherwise, the task
1060 -- continues its execution, and the state of the suspension object
1061 -- is set to False (ARM D.10 par. 9).
1067 Result
:= pthread_cond_wait
(S
.CV
'Access, S
.L
'Access);
1070 Result
:= pthread_mutex_unlock
(S
.L
'Access);
1071 pragma Assert
(Result
= 0);
1073 SSL
.Abort_Undefer
.all;
1075 end Suspend_Until_True
;
1083 function Check_Exit
(Self_ID
: ST
.Task_Id
) return Boolean is
1084 pragma Unreferenced
(Self_ID
);
1089 --------------------
1090 -- Check_No_Locks --
1091 --------------------
1093 function Check_No_Locks
(Self_ID
: ST
.Task_Id
) return Boolean is
1094 pragma Unreferenced
(Self_ID
);
1099 ----------------------
1100 -- Environment_Task --
1101 ----------------------
1103 function Environment_Task
return Task_Id
is
1105 return Environment_Task_Id
;
1106 end Environment_Task
;
1112 procedure Lock_RTS
is
1114 Write_Lock
(Single_RTS_Lock
'Access, Global_Lock
=> True);
1121 procedure Unlock_RTS
is
1123 Unlock
(Single_RTS_Lock
'Access, Global_Lock
=> True);
1130 function Suspend_Task
1132 Thread_Self
: Thread_Id
) return Boolean
1134 pragma Unreferenced
(T
);
1135 pragma Unreferenced
(Thread_Self
);
1144 function Resume_Task
1146 Thread_Self
: Thread_Id
) return Boolean
1148 pragma Unreferenced
(T
);
1149 pragma Unreferenced
(Thread_Self
);
1158 procedure Initialize
(Environment_Task
: Task_Id
) is
1160 Environment_Task_Id
:= Environment_Task
;
1162 SSL
.Get_Exc_Stack_Addr
:= Get_Exc_Stack_Addr
'Access;
1164 -- Initialize the lock used to synchronize chain of all ATCBs
1166 Initialize_Lock
(Single_RTS_Lock
'Access, RTS_Lock_Level
);
1168 Specific
.Initialize
(Environment_Task
);
1170 Enter_Task
(Environment_Task
);
1173 end System
.Task_Primitives
.Operations
;