1------------------------------------------------------------------------------
2--                                                                          --
3--                 GNAT RUN-TIME LIBRARY (GNARL) COMPONENTS                 --
4--                                                                          --
5--                  SYSTEM.TASK_PRIMITIVES.OPERATIONS.DEC                   --
6--                                                                          --
7--                                  B o d y                                 --
8--                                                                          --
9--          Copyright (C) 2000-2009, Free Software Foundation, Inc.         --
10--                                                                          --
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 3,  or (at your option) any later ver- --
14-- sion.  GNAT 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.                                     --
17--                                                                          --
18-- As a special exception under Section 7 of GPL version 3, you are granted --
19-- additional permissions described in the GCC Runtime Library Exception,   --
20-- version 3.1, as published by the Free Software Foundation.               --
21--                                                                          --
22-- You should have received a copy of the GNU General Public License and    --
23-- a copy of the GCC Runtime Library Exception along with this program;     --
24-- see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see    --
25-- <http://www.gnu.org/licenses/>.                                          --
26--                                                                          --
27-- GNARL was developed by the GNARL team at Florida State University.       --
28-- Extensive contributions were provided by Ada Core Technologies, Inc.     --
29--                                                                          --
30------------------------------------------------------------------------------
31
32--   This package is for OpenVMS/Alpha
33
34with System.OS_Interface;
35with System.Parameters;
36with System.Tasking;
37with Ada.Unchecked_Conversion;
38with System.Soft_Links;
39
40package body System.Task_Primitives.Operations.DEC is
41
42   use System.OS_Interface;
43   use System.Parameters;
44   use System.Tasking;
45   use System.Aux_DEC;
46   use type Interfaces.C.int;
47
48   package SSL renames System.Soft_Links;
49
50   --  The FAB_RAB_Type specifies where the context field (the calling
51   --  task) is stored.  Other fields defined for FAB_RAB arent' need and
52   --  so are ignored.
53
54   type FAB_RAB_Type is record
55      CTX : Unsigned_Longword;
56   end record;
57
58   for FAB_RAB_Type use record
59      CTX at 24 range 0 .. 31;
60   end record;
61
62   for FAB_RAB_Type'Size use 224;
63
64   type FAB_RAB_Access_Type is access all FAB_RAB_Type;
65
66   -----------------------
67   -- Local Subprograms --
68   -----------------------
69
70   function To_Unsigned_Longword is new
71     Ada.Unchecked_Conversion (Task_Id, Unsigned_Longword);
72
73   function To_Task_Id is new
74     Ada.Unchecked_Conversion (Unsigned_Longword, Task_Id);
75
76   function To_FAB_RAB is new
77     Ada.Unchecked_Conversion (Address, FAB_RAB_Access_Type);
78
79   ---------------------------
80   -- Interrupt_AST_Handler --
81   ---------------------------
82
83   procedure Interrupt_AST_Handler (ID : Address) is
84      Result      : Interfaces.C.int;
85      AST_Self_ID : constant Task_Id := To_Task_Id (ID);
86   begin
87      Result := pthread_cond_signal_int_np (AST_Self_ID.Common.LL.CV'Access);
88      pragma Assert (Result = 0);
89   end Interrupt_AST_Handler;
90
91   ---------------------
92   -- RMS_AST_Handler --
93   ---------------------
94
95   procedure RMS_AST_Handler (ID : Address) is
96      AST_Self_ID : constant Task_Id := To_Task_Id (To_FAB_RAB (ID).CTX);
97      Result      : Interfaces.C.int;
98
99   begin
100      AST_Self_ID.Common.LL.AST_Pending := False;
101      Result := pthread_cond_signal_int_np (AST_Self_ID.Common.LL.CV'Access);
102      pragma Assert (Result = 0);
103   end RMS_AST_Handler;
104
105   ----------
106   -- Self --
107   ----------
108
109   function Self return Unsigned_Longword is
110      Self_ID : constant Task_Id := Self;
111   begin
112      Self_ID.Common.LL.AST_Pending := True;
113      return To_Unsigned_Longword (Self);
114   end Self;
115
116   -------------------------
117   -- Starlet_AST_Handler --
118   -------------------------
119
120   procedure Starlet_AST_Handler (ID : Address) is
121      Result      : Interfaces.C.int;
122      AST_Self_ID : constant Task_Id := To_Task_Id (ID);
123   begin
124      AST_Self_ID.Common.LL.AST_Pending := False;
125      Result := pthread_cond_signal_int_np (AST_Self_ID.Common.LL.CV'Access);
126      pragma Assert (Result = 0);
127   end Starlet_AST_Handler;
128
129   ----------------
130   -- Task_Synch --
131   ----------------
132
133   procedure Task_Synch is
134      Synch_Self_ID : constant Task_Id := Self;
135
136   begin
137      if Single_Lock then
138         Lock_RTS;
139      else
140         Write_Lock (Synch_Self_ID);
141      end if;
142
143      SSL.Abort_Defer.all;
144      Synch_Self_ID.Common.State := AST_Server_Sleep;
145
146      while Synch_Self_ID.Common.LL.AST_Pending loop
147         Sleep (Synch_Self_ID, AST_Server_Sleep);
148      end loop;
149
150      Synch_Self_ID.Common.State := Runnable;
151
152      if Single_Lock then
153         Unlock_RTS;
154      else
155         Unlock (Synch_Self_ID);
156      end if;
157
158      SSL.Abort_Undefer.all;
159   end Task_Synch;
160
161end System.Task_Primitives.Operations.DEC;
162