1 ------------------------------------------------------------------------------
3 -- GNAT RUN-TIME LIBRARY (GNARL) COMPONENTS --
5 -- SYSTEM.TASK_PRIMITIVES.OPERATIONS.SPECIFIC --
9 -- Copyright (C) 1992-2011, 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 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. --
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. --
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/>. --
27 -- GNARL was developed by the GNARL team at Florida State University. --
28 -- Extensive contributions were provided by Ada Core Technologies, Inc. --
30 ------------------------------------------------------------------------------
32 -- This is a VMS version of this package where foreign threads are
35 separate (System.Task_Primitives.Operations)
36 package body Specific is
42 procedure Initialize (Environment_Task : Task_Id) is
43 pragma Warnings (Off, Environment_Task);
44 Result : Interfaces.C.int;
47 Result := pthread_key_create (ATCB_Key'Access, null);
48 pragma Assert (Result = 0);
55 function Is_Valid_Task return Boolean is
57 return pthread_getspecific (ATCB_Key) /= System.Null_Address;
64 procedure Set (Self_Id : Task_Id) is
65 Result : Interfaces.C.int;
67 Result := pthread_setspecific (ATCB_Key, To_Address (Self_Id));
68 pragma Assert (Result = 0);
75 -- To make Ada tasks and C threads interoperate better, we have added some
76 -- functionality to Self. Suppose a C main program (with threads) calls an
77 -- Ada procedure and the Ada procedure calls the tasking runtime system.
78 -- Eventually, a call will be made to self. Since the call is not coming
79 -- from an Ada task, there will be no corresponding ATCB.
81 -- What we do in Self is to catch references that do not come from
82 -- recognized Ada tasks, and create an ATCB for the calling thread.
84 -- The new ATCB will be "detached" from the normal Ada task master
85 -- hierarchy, much like the existing implicitly created signal-server
88 function Self return Task_Id is
89 Result : System.Address;
92 Result := pthread_getspecific (ATCB_Key);
94 -- If the key value is Null then it is a non-Ada task
96 if Result /= System.Null_Address then
97 return To_Task_Id (Result);
99 return Register_Foreign_Thread;