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 IRIX (pthread library) 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.
47 with System.Task_Info;
49 with System.Tasking.Debug;
50 -- used for Known_Tasks
52 with System.Interrupt_Management;
53 -- used for Keep_Unmasked
54 -- Abort_Task_Interrupt
57 with System.OS_Primitives;
58 -- used for Delay_Modes
63 with System.Soft_Links;
64 -- used for Abort_Defer/Undefer
66 -- We use System.Soft_Links instead of System.Tasking.Initialization
67 -- because the later is a higher level package that we shouldn't depend on.
68 -- For example when using the restricted run time, it is replaced by
69 -- System.Tasking.Restricted.Stages.
71 with Unchecked_Conversion;
72 with Unchecked_Deallocation;
74 package body System.Task_Primitives.Operations is
76 package SSL renames System.Soft_Links;
79 use System.Tasking.Debug;
81 use System.OS_Interface;
82 use System.OS_Primitives;
83 use System.Parameters;
89 -- The followings are logically constants, but need to be initialized
92 Single_RTS_Lock : aliased RTS_Lock;
93 -- This is a lock to allow only one thread of control in the RTS at
94 -- a time; it is used to execute in mutual exclusion from all other tasks.
95 -- Used mainly in Single_Lock mode, but also to protect All_Tasks_List
97 ATCB_Key : aliased pthread_key_t;
98 -- Key used to find the Ada Task_Id associated with a thread
100 Environment_Task_Id : Task_Id;
101 -- A variable to hold Task_Id for the environment task
103 Locking_Policy : Character;
104 pragma Import (C, Locking_Policy, "__gl_locking_policy");
106 Real_Time_Clock_Id : constant clockid_t := CLOCK_REALTIME;
108 Unblocked_Signal_Mask : aliased sigset_t;
110 Foreign_Task_Elaborated : aliased Boolean := True;
111 -- Used to identified fake tasks (i.e., non-Ada Threads)
119 procedure Initialize (Environment_Task : Task_Id);
120 pragma Inline (Initialize);
121 -- Initialize various data needed by this package
123 function Is_Valid_Task return Boolean;
124 pragma Inline (Is_Valid_Task);
125 -- Does executing thread have a TCB?
127 procedure Set (Self_Id : Task_Id);
129 -- Set the self id for the current task
131 function Self return Task_Id;
132 pragma Inline (Self);
133 -- Return a pointer to the Ada Task Control Block of the calling task
137 package body Specific is separate;
138 -- The body of this package is target specific
140 ---------------------------------
141 -- Support for foreign threads --
142 ---------------------------------
144 function Register_Foreign_Thread (Thread : Thread_Id) return Task_Id;
145 -- Allocate and Initialize a new ATCB for the current Thread
147 function Register_Foreign_Thread
148 (Thread : Thread_Id) return Task_Id is separate;
150 -----------------------
151 -- Local Subprograms --
152 -----------------------
154 function To_Address is new Unchecked_Conversion (Task_Id, System.Address);
156 procedure Abort_Handler (Sig : Signal);
157 -- Signal handler used to implement asynchronous abort
163 procedure Abort_Handler (Sig : Signal) is
164 pragma Unreferenced (Sig);
166 T : constant Task_Id := Self;
167 Result : Interfaces.C.int;
168 Old_Set : aliased sigset_t;
171 -- It is not safe to raise an exception when using ZCX and the GCC
172 -- exception handling mechanism.
174 if ZCX_By_Default and then GCC_ZCX_Support then
178 if T.Deferral_Level = 0
179 and then T.Pending_ATC_Level < T.ATC_Nesting_Level
181 -- Make sure signals used for RTS internal purpose are unmasked
183 Result := pthread_sigmask
185 Unblocked_Signal_Mask'Unchecked_Access,
186 Old_Set'Unchecked_Access);
187 pragma Assert (Result = 0);
189 raise Standard'Abort_Signal;
197 -- The underlying thread system sets a guard page at the
198 -- bottom of a thread stack, so nothing is needed.
200 procedure Stack_Guard (T : ST.Task_Id; On : Boolean) is
201 pragma Unreferenced (On);
202 pragma Unreferenced (T);
211 function Get_Thread_Id (T : ST.Task_Id) return OSI.Thread_Id is
213 return T.Common.LL.Thread;
220 function Self return Task_Id renames Specific.Self;
222 ---------------------
223 -- Initialize_Lock --
224 ---------------------
226 -- Note: mutexes and cond_variables needed per-task basis are
227 -- initialized in Initialize_TCB and the Storage_Error is
228 -- handled. Other mutexes (such as RTS_Lock, Memory_Lock...)
229 -- used in RTS is initialized before any status change of RTS.
230 -- Therefore rasing Storage_Error in the following routines
231 -- should be able to be handled safely.
233 procedure Initialize_Lock
234 (Prio : System.Any_Priority;
237 Attributes : aliased pthread_mutexattr_t;
238 Result : Interfaces.C.int;
241 Result := pthread_mutexattr_init (Attributes'Access);
242 pragma Assert (Result = 0 or else Result = ENOMEM);
244 if Result = ENOMEM then
248 if Locking_Policy = 'C' then
249 Result := pthread_mutexattr_setprotocol
250 (Attributes'Access, PTHREAD_PRIO_PROTECT);
251 pragma Assert (Result = 0);
253 Result := pthread_mutexattr_setprioceiling
254 (Attributes'Access, Interfaces.C.int (Prio));
255 pragma Assert (Result = 0);
258 Result := pthread_mutex_init (L, Attributes'Access);
259 pragma Assert (Result = 0 or else Result = ENOMEM);
261 if Result = ENOMEM then
262 Result := pthread_mutexattr_destroy (Attributes'Access);
266 Result := pthread_mutexattr_destroy (Attributes'Access);
267 pragma Assert (Result = 0);
270 procedure Initialize_Lock (L : access RTS_Lock; Level : Lock_Level) is
271 pragma Unreferenced (Level);
273 Attributes : aliased pthread_mutexattr_t;
274 Result : Interfaces.C.int;
277 Result := pthread_mutexattr_init (Attributes'Access);
278 pragma Assert (Result = 0 or else Result = ENOMEM);
280 if Result = ENOMEM then
284 if Locking_Policy = 'C' then
285 Result := pthread_mutexattr_setprotocol
286 (Attributes'Access, PTHREAD_PRIO_PROTECT);
287 pragma Assert (Result = 0);
289 Result := pthread_mutexattr_setprioceiling
290 (Attributes'Access, Interfaces.C.int (System.Any_Priority'Last));
291 pragma Assert (Result = 0);
294 Result := pthread_mutex_init (L, Attributes'Access);
296 pragma Assert (Result = 0 or else Result = ENOMEM);
298 if Result = ENOMEM then
299 Result := pthread_mutexattr_destroy (Attributes'Access);
303 Result := pthread_mutexattr_destroy (Attributes'Access);
310 procedure Finalize_Lock (L : access Lock) is
311 Result : Interfaces.C.int;
313 Result := pthread_mutex_destroy (L);
314 pragma Assert (Result = 0);
317 procedure Finalize_Lock (L : access RTS_Lock) is
318 Result : Interfaces.C.int;
320 Result := pthread_mutex_destroy (L);
321 pragma Assert (Result = 0);
328 procedure Write_Lock (L : access Lock; Ceiling_Violation : out Boolean) is
329 Result : Interfaces.C.int;
331 Result := pthread_mutex_lock (L);
332 Ceiling_Violation := Result = EINVAL;
334 -- Assumes the cause of EINVAL is a priority ceiling violation
336 pragma Assert (Result = 0 or else Result = EINVAL);
340 (L : access RTS_Lock;
341 Global_Lock : Boolean := False)
343 Result : Interfaces.C.int;
345 if not Single_Lock or else Global_Lock then
346 Result := pthread_mutex_lock (L);
347 pragma Assert (Result = 0);
351 procedure Write_Lock (T : Task_Id) is
352 Result : Interfaces.C.int;
354 if not Single_Lock then
355 Result := pthread_mutex_lock (T.Common.LL.L'Access);
356 pragma Assert (Result = 0);
364 procedure Read_Lock (L : access Lock; Ceiling_Violation : out Boolean) is
366 Write_Lock (L, Ceiling_Violation);
373 procedure Unlock (L : access Lock) is
374 Result : Interfaces.C.int;
376 Result := pthread_mutex_unlock (L);
377 pragma Assert (Result = 0);
380 procedure Unlock (L : access RTS_Lock; Global_Lock : Boolean := False) is
381 Result : Interfaces.C.int;
384 if not Single_Lock or else Global_Lock then
385 Result := pthread_mutex_unlock (L);
386 pragma Assert (Result = 0);
390 procedure Unlock (T : Task_Id) is
391 Result : Interfaces.C.int;
394 if not Single_Lock then
395 Result := pthread_mutex_unlock (T.Common.LL.L'Access);
396 pragma Assert (Result = 0);
405 (Self_ID : ST.Task_Id;
406 Reason : System.Tasking.Task_States)
408 pragma Unreferenced (Reason);
410 Result : Interfaces.C.int;
414 Result := pthread_cond_wait
415 (Self_ID.Common.LL.CV'Access, Single_RTS_Lock'Access);
417 Result := pthread_cond_wait
418 (Self_ID.Common.LL.CV'Access, Self_ID.Common.LL.L'Access);
421 -- EINTR is not considered a failure
423 pragma Assert (Result = 0 or else Result = EINTR);
430 procedure Timed_Sleep
433 Mode : ST.Delay_Modes;
434 Reason : Task_States;
435 Timedout : out Boolean;
436 Yielded : out Boolean)
438 pragma Unreferenced (Reason);
440 Check_Time : constant Duration := Monotonic_Clock;
442 Request : aliased timespec;
443 Result : Interfaces.C.int;
449 if Mode = Relative then
450 Abs_Time := Duration'Min (Time, Max_Sensible_Delay) + Check_Time;
452 Abs_Time := Duration'Min (Check_Time + Max_Sensible_Delay, Time);
455 if Abs_Time > Check_Time then
456 Request := To_Timespec (Abs_Time);
459 exit when Self_ID.Pending_ATC_Level < Self_ID.ATC_Nesting_Level
460 or else Self_ID.Pending_Priority_Change;
463 Result := pthread_cond_timedwait
464 (Self_ID.Common.LL.CV'Access, Single_RTS_Lock'Access,
468 Result := pthread_cond_timedwait
469 (Self_ID.Common.LL.CV'Access, Self_ID.Common.LL.L'Access,
473 exit when Abs_Time <= Monotonic_Clock;
475 if Result = 0 or else errno = EINTR then
487 -- This is for use in implementing delay statements, so we assume
488 -- the caller is abort-deferred but is holding no locks.
490 procedure Timed_Delay
493 Mode : ST.Delay_Modes)
495 Check_Time : constant Duration := Monotonic_Clock;
497 Request : aliased timespec;
498 Result : Interfaces.C.int;
505 Write_Lock (Self_ID);
507 if Mode = Relative then
508 Abs_Time := Time + Check_Time;
510 Abs_Time := Duration'Min (Check_Time + Max_Sensible_Delay, Time);
513 if Abs_Time > Check_Time then
514 Request := To_Timespec (Abs_Time);
515 Self_ID.Common.State := Delay_Sleep;
518 if Self_ID.Pending_Priority_Change then
519 Self_ID.Pending_Priority_Change := False;
520 Self_ID.Common.Base_Priority := Self_ID.New_Base_Priority;
521 Set_Priority (Self_ID, Self_ID.Common.Base_Priority);
524 exit when Self_ID.Pending_ATC_Level < Self_ID.ATC_Nesting_Level;
526 Result := pthread_cond_timedwait (Self_ID.Common.LL.CV'Access,
527 Self_ID.Common.LL.L'Access, Request'Access);
528 exit when Abs_Time <= Monotonic_Clock;
530 pragma Assert (Result = 0
531 or else Result = ETIMEDOUT
532 or else Result = EINTR);
535 Self_ID.Common.State := Runnable;
547 ---------------------
548 -- Monotonic_Clock --
549 ---------------------
551 function Monotonic_Clock return Duration is
552 TS : aliased timespec;
553 Result : Interfaces.C.int;
555 Result := clock_gettime (Real_Time_Clock_Id, TS'Unchecked_Access);
556 pragma Assert (Result = 0);
557 return To_Duration (TS);
564 function RT_Resolution return Duration is
566 -- The clock_getres (Real_Time_Clock_Id) function appears to return
567 -- the interrupt resolution of the realtime clock and not the actual
568 -- resolution of reading the clock. Even though this last value is
569 -- only guaranteed to be 100 Hz, at least the Origin 200 appears to
570 -- have a microsecond resolution or better.
572 -- ??? We should figure out a method to return the right value on
582 procedure Wakeup (T : ST.Task_Id; Reason : System.Tasking.Task_States) is
583 pragma Unreferenced (Reason);
584 Result : Interfaces.C.int;
586 Result := pthread_cond_signal (T.Common.LL.CV'Access);
587 pragma Assert (Result = 0);
594 procedure Yield (Do_Yield : Boolean := True) is
595 Result : Interfaces.C.int;
596 pragma Unreferenced (Result);
599 Result := sched_yield;
607 procedure Set_Priority
609 Prio : System.Any_Priority;
610 Loss_Of_Inheritance : Boolean := False)
612 pragma Unreferenced (Loss_Of_Inheritance);
614 Result : Interfaces.C.int;
615 Param : aliased struct_sched_param;
616 Sched_Policy : Interfaces.C.int;
618 use type System.Task_Info.Task_Info_Type;
620 function To_Int is new Unchecked_Conversion
621 (System.Task_Info.Thread_Scheduling_Policy, Interfaces.C.int);
624 T.Common.Current_Priority := Prio;
625 Param.sched_priority := Interfaces.C.int (Prio);
627 if T.Common.Task_Info /= null then
628 Sched_Policy := To_Int (T.Common.Task_Info.Policy);
630 Sched_Policy := SCHED_FIFO;
633 Result := pthread_setschedparam (T.Common.LL.Thread, Sched_Policy,
635 pragma Assert (Result = 0);
642 function Get_Priority (T : Task_Id) return System.Any_Priority is
644 return T.Common.Current_Priority;
651 procedure Enter_Task (Self_ID : Task_Id) is
652 Result : Interfaces.C.int;
654 function To_Int is new Unchecked_Conversion
655 (System.Task_Info.CPU_Number, Interfaces.C.int);
657 use System.Task_Info;
660 Self_ID.Common.LL.Thread := pthread_self;
661 Specific.Set (Self_ID);
663 if Self_ID.Common.Task_Info /= null
664 and then Self_ID.Common.Task_Info.Scope = PTHREAD_SCOPE_SYSTEM
665 and then Self_ID.Common.Task_Info.Runon_CPU /= ANY_CPU
667 Result := pthread_setrunon_np
668 (To_Int (Self_ID.Common.Task_Info.Runon_CPU));
669 pragma Assert (Result = 0);
674 for J in Known_Tasks'Range loop
675 if Known_Tasks (J) = null then
676 Known_Tasks (J) := Self_ID;
677 Self_ID.Known_Tasks_Index := J;
689 function New_ATCB (Entry_Num : Task_Entry_Index) return Task_Id is
691 return new Ada_Task_Control_Block (Entry_Num);
698 function Is_Valid_Task return Boolean renames Specific.Is_Valid_Task;
700 -----------------------------
701 -- Register_Foreign_Thread --
702 -----------------------------
704 function Register_Foreign_Thread return Task_Id is
706 if Is_Valid_Task then
709 return Register_Foreign_Thread (pthread_self);
711 end Register_Foreign_Thread;
717 procedure Initialize_TCB (Self_ID : Task_Id; Succeeded : out Boolean) is
718 Result : Interfaces.C.int;
719 Cond_Attr : aliased pthread_condattr_t;
722 if not Single_Lock then
723 Initialize_Lock (Self_ID.Common.LL.L'Access, ATCB_Level);
726 Result := pthread_condattr_init (Cond_Attr'Access);
727 pragma Assert (Result = 0 or else Result = ENOMEM);
730 Result := pthread_cond_init (Self_ID.Common.LL.CV'Access,
732 pragma Assert (Result = 0 or else Result = ENOMEM);
738 if not Single_Lock then
739 Result := pthread_mutex_destroy (Self_ID.Common.LL.L'Access);
740 pragma Assert (Result = 0);
746 Result := pthread_condattr_destroy (Cond_Attr'Access);
747 pragma Assert (Result = 0);
754 procedure Create_Task
756 Wrapper : System.Address;
757 Stack_Size : System.Parameters.Size_Type;
758 Priority : System.Any_Priority;
759 Succeeded : out Boolean)
761 use System.Task_Info;
763 Attributes : aliased pthread_attr_t;
764 Sched_Param : aliased struct_sched_param;
765 Result : Interfaces.C.int;
767 function Thread_Body_Access is new
768 Unchecked_Conversion (System.Address, Thread_Body);
770 function To_Int is new Unchecked_Conversion
771 (System.Task_Info.Thread_Scheduling_Scope, Interfaces.C.int);
772 function To_Int is new Unchecked_Conversion
773 (System.Task_Info.Thread_Scheduling_Inheritance, Interfaces.C.int);
774 function To_Int is new Unchecked_Conversion
775 (System.Task_Info.Thread_Scheduling_Policy, Interfaces.C.int);
778 Result := pthread_attr_init (Attributes'Access);
779 pragma Assert (Result = 0 or else Result = ENOMEM);
786 Result := pthread_attr_setdetachstate
787 (Attributes'Access, PTHREAD_CREATE_DETACHED);
788 pragma Assert (Result = 0);
790 Result := pthread_attr_setstacksize
791 (Attributes'Access, Interfaces.C.size_t (Stack_Size));
792 pragma Assert (Result = 0);
794 if T.Common.Task_Info /= null then
795 Result := pthread_attr_setscope
796 (Attributes'Access, To_Int (T.Common.Task_Info.Scope));
797 pragma Assert (Result = 0);
799 Result := pthread_attr_setinheritsched
800 (Attributes'Access, To_Int (T.Common.Task_Info.Inheritance));
801 pragma Assert (Result = 0);
803 Result := pthread_attr_setschedpolicy
804 (Attributes'Access, To_Int (T.Common.Task_Info.Policy));
805 pragma Assert (Result = 0);
807 Sched_Param.sched_priority :=
808 Interfaces.C.int (T.Common.Task_Info.Priority);
810 Result := pthread_attr_setschedparam
811 (Attributes'Access, Sched_Param'Access);
812 pragma Assert (Result = 0);
815 -- Since the initial signal mask of a thread is inherited from the
816 -- creator, and the Environment task has all its signals masked, we
817 -- do not need to manipulate caller's signal mask at this point.
818 -- All tasks in RTS will have All_Tasks_Mask initially.
820 Result := pthread_create
821 (T.Common.LL.Thread'Access,
823 Thread_Body_Access (Wrapper),
827 and then T.Common.Task_Info /= null
828 and then T.Common.Task_Info.Scope = PTHREAD_SCOPE_SYSTEM
830 -- The pthread_create call may have failed because we
831 -- asked for a system scope pthread and none were
832 -- available (probably because the program was not executed
833 -- by the superuser). Let's try for a process scope pthread
834 -- instead of raising Tasking_Error.
837 ("Request for PTHREAD_SCOPE_SYSTEM in Task_Info pragma for task");
838 System.IO.Put ("""");
839 System.IO.Put (T.Common.Task_Image (1 .. T.Common.Task_Image_Len));
840 System.IO.Put_Line (""" could not be honored. ");
841 System.IO.Put_Line ("Scope changed to PTHREAD_SCOPE_PROCESS");
843 T.Common.Task_Info.Scope := PTHREAD_SCOPE_PROCESS;
844 Result := pthread_attr_setscope
845 (Attributes'Access, To_Int (T.Common.Task_Info.Scope));
846 pragma Assert (Result = 0);
848 Result := pthread_create
849 (T.Common.LL.Thread'Access,
851 Thread_Body_Access (Wrapper),
855 pragma Assert (Result = 0 or else Result = EAGAIN);
857 Succeeded := Result = 0;
859 -- The following needs significant commenting ???
861 if T.Common.Task_Info /= null then
862 T.Common.Base_Priority := T.Common.Task_Info.Priority;
863 Set_Priority (T, T.Common.Task_Info.Priority);
865 Set_Priority (T, Priority);
868 Result := pthread_attr_destroy (Attributes'Access);
869 pragma Assert (Result = 0);
876 procedure Finalize_TCB (T : Task_Id) is
877 Result : Interfaces.C.int;
879 Is_Self : constant Boolean := T = Self;
881 procedure Free is new
882 Unchecked_Deallocation (Ada_Task_Control_Block, Task_Id);
885 if not Single_Lock then
886 Result := pthread_mutex_destroy (T.Common.LL.L'Access);
887 pragma Assert (Result = 0);
890 Result := pthread_cond_destroy (T.Common.LL.CV'Access);
891 pragma Assert (Result = 0);
893 if T.Known_Tasks_Index /= -1 then
894 Known_Tasks (T.Known_Tasks_Index) := null;
908 procedure Exit_Task is
917 procedure Abort_Task (T : Task_Id) is
918 Result : Interfaces.C.int;
920 Result := pthread_kill (T.Common.LL.Thread,
921 Signal (System.Interrupt_Management.Abort_Task_Interrupt));
922 pragma Assert (Result = 0);
929 procedure Initialize (S : in out Suspension_Object) is
930 Mutex_Attr : aliased pthread_mutexattr_t;
931 Cond_Attr : aliased pthread_condattr_t;
932 Result : Interfaces.C.int;
934 -- Initialize internal state. It is always initialized to False (ARM
940 -- Initialize internal mutex
942 Result := pthread_mutexattr_init (Mutex_Attr'Access);
943 pragma Assert (Result = 0 or else Result = ENOMEM);
945 if Result = ENOMEM then
949 Result := pthread_mutex_init (S.L'Access, Mutex_Attr'Access);
950 pragma Assert (Result = 0 or else Result = ENOMEM);
952 if Result = ENOMEM then
953 Result := pthread_mutexattr_destroy (Mutex_Attr'Access);
954 pragma Assert (Result = 0);
959 Result := pthread_mutexattr_destroy (Mutex_Attr'Access);
960 pragma Assert (Result = 0);
962 -- Initialize internal condition variable
964 Result := pthread_condattr_init (Cond_Attr'Access);
965 pragma Assert (Result = 0 or else Result = ENOMEM);
968 Result := pthread_mutex_destroy (S.L'Access);
969 pragma Assert (Result = 0);
971 if Result = ENOMEM then
976 Result := pthread_cond_init (S.CV'Access, Cond_Attr'Access);
977 pragma Assert (Result = 0 or else Result = ENOMEM);
980 Result := pthread_mutex_destroy (S.L'Access);
981 pragma Assert (Result = 0);
983 if Result = ENOMEM then
984 Result := pthread_condattr_destroy (Cond_Attr'Access);
985 pragma Assert (Result = 0);
991 Result := pthread_condattr_destroy (Cond_Attr'Access);
992 pragma Assert (Result = 0);
999 procedure Finalize (S : in out Suspension_Object) is
1000 Result : Interfaces.C.int;
1002 -- Destroy internal mutex
1004 Result := pthread_mutex_destroy (S.L'Access);
1005 pragma Assert (Result = 0);
1007 -- Destroy internal condition variable
1009 Result := pthread_cond_destroy (S.CV'Access);
1010 pragma Assert (Result = 0);
1017 function Current_State (S : Suspension_Object) return Boolean is
1019 -- We do not want to use lock on this read operation. State is marked
1020 -- as Atomic so that we ensure that the value retrieved is correct.
1029 procedure Set_False (S : in out Suspension_Object) is
1030 Result : Interfaces.C.int;
1032 SSL.Abort_Defer.all;
1034 Result := pthread_mutex_lock (S.L'Access);
1035 pragma Assert (Result = 0);
1039 Result := pthread_mutex_unlock (S.L'Access);
1040 pragma Assert (Result = 0);
1042 SSL.Abort_Undefer.all;
1049 procedure Set_True (S : in out Suspension_Object) is
1050 Result : Interfaces.C.int;
1052 SSL.Abort_Defer.all;
1054 Result := pthread_mutex_lock (S.L'Access);
1055 pragma Assert (Result = 0);
1057 -- If there is already a task waiting on this suspension object then
1058 -- we resume it, leaving the state of the suspension object to False,
1059 -- as it is specified in ARM D.10 par. 9. Otherwise, it just leaves
1060 -- the state to True.
1066 Result := pthread_cond_signal (S.CV'Access);
1067 pragma Assert (Result = 0);
1072 Result := pthread_mutex_unlock (S.L'Access);
1073 pragma Assert (Result = 0);
1075 SSL.Abort_Undefer.all;
1078 ------------------------
1079 -- Suspend_Until_True --
1080 ------------------------
1082 procedure Suspend_Until_True (S : in out Suspension_Object) is
1083 Result : Interfaces.C.int;
1085 SSL.Abort_Defer.all;
1087 Result := pthread_mutex_lock (S.L'Access);
1088 pragma Assert (Result = 0);
1091 -- Program_Error must be raised upon calling Suspend_Until_True
1092 -- if another task is already waiting on that suspension object
1093 -- (ARM D.10 par. 10).
1095 Result := pthread_mutex_unlock (S.L'Access);
1096 pragma Assert (Result = 0);
1098 SSL.Abort_Undefer.all;
1100 raise Program_Error;
1102 -- Suspend the task if the state is False. Otherwise, the task
1103 -- continues its execution, and the state of the suspension object
1104 -- is set to False (ARM D.10 par. 9).
1110 Result := pthread_cond_wait (S.CV'Access, S.L'Access);
1113 Result := pthread_mutex_unlock (S.L'Access);
1114 pragma Assert (Result = 0);
1116 SSL.Abort_Undefer.all;
1118 end Suspend_Until_True;
1126 function Check_Exit (Self_ID : ST.Task_Id) return Boolean is
1127 pragma Unreferenced (Self_ID);
1132 --------------------
1133 -- Check_No_Locks --
1134 --------------------
1136 function Check_No_Locks (Self_ID : ST.Task_Id) return Boolean is
1137 pragma Unreferenced (Self_ID);
1142 ----------------------
1143 -- Environment_Task --
1144 ----------------------
1146 function Environment_Task return Task_Id is
1148 return Environment_Task_Id;
1149 end Environment_Task;
1155 procedure Lock_RTS is
1157 Write_Lock (Single_RTS_Lock'Access, Global_Lock => True);
1164 procedure Unlock_RTS is
1166 Unlock (Single_RTS_Lock'Access, Global_Lock => True);
1173 function Suspend_Task
1175 Thread_Self : Thread_Id) return Boolean
1177 pragma Unreferenced (T);
1178 pragma Unreferenced (Thread_Self);
1187 function Resume_Task
1189 Thread_Self : Thread_Id) return Boolean
1191 pragma Unreferenced (T);
1192 pragma Unreferenced (Thread_Self);
1201 procedure Initialize (Environment_Task : Task_Id) is
1202 act : aliased struct_sigaction;
1203 old_act : aliased struct_sigaction;
1204 Tmp_Set : aliased sigset_t;
1205 Result : Interfaces.C.int;
1208 (Int : System.Interrupt_Management.Interrupt_ID) return Character;
1209 pragma Import (C, State, "__gnat_get_interrupt_state");
1210 -- Get interrupt state. Defined in a-init.c. The input argument is
1211 -- the interrupt number, and the result is one of the following:
1213 Default : constant Character := 's';
1214 -- 'n' this interrupt not set by any Interrupt_State pragma
1215 -- 'u' Interrupt_State pragma set state to User
1216 -- 'r' Interrupt_State pragma set state to Runtime
1217 -- 's' Interrupt_State pragma set state to System (use "default"
1221 Environment_Task_Id := Environment_Task;
1223 Interrupt_Management.Initialize;
1225 -- Initialize the lock used to synchronize chain of all ATCBs.
1227 Initialize_Lock (Single_RTS_Lock'Access, RTS_Lock_Level);
1229 Specific.Initialize (Environment_Task);
1231 Enter_Task (Environment_Task);
1233 -- Prepare the set of signals that should unblocked in all tasks
1235 Result := sigemptyset (Unblocked_Signal_Mask'Access);
1236 pragma Assert (Result = 0);
1238 for J in Interrupt_Management.Interrupt_ID loop
1239 if System.Interrupt_Management.Keep_Unmasked (J) then
1240 Result := sigaddset (Unblocked_Signal_Mask'Access, Signal (J));
1241 pragma Assert (Result = 0);
1245 -- Install the abort-signal handler
1247 if State (System.Interrupt_Management.Abort_Task_Interrupt)
1251 act.sa_handler := Abort_Handler'Address;
1253 Result := sigemptyset (Tmp_Set'Access);
1254 pragma Assert (Result = 0);
1255 act.sa_mask := Tmp_Set;
1259 Signal (System.Interrupt_Management.Abort_Task_Interrupt),
1260 act'Unchecked_Access,
1261 old_act'Unchecked_Access);
1262 pragma Assert (Result = 0);
1266 end System.Task_Primitives.Operations;