1 ------------------------------------------------------------------------------
3 -- GNAT RUN-TIME LIBRARY (GNARL) COMPONENTS --
5 -- SYSTEM.TASK_PRIMITIVES.OPERATIONS.SPECIFIC --
9 -- Copyright (C) 1992-2007, 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 POSIX version of this package where foreign threads are
37 -- Currently, DEC Unix, SCO UnixWare, Solaris pthread, HPUX pthread and
38 -- GNU/Linux threads use this version.
40 separate (System.Task_Primitives.Operations)
41 package body Specific is
47 procedure Initialize (Environment_Task : Task_Id) is
48 pragma Warnings (Off, Environment_Task);
49 Result : Interfaces.C.int;
52 Result := pthread_key_create (ATCB_Key'Access, null);
53 pragma Assert (Result = 0);
60 function Is_Valid_Task return Boolean is
62 return pthread_getspecific (ATCB_Key) /= System.Null_Address;
69 procedure Set (Self_Id : Task_Id) is
70 Result : Interfaces.C.int;
72 Result := pthread_setspecific (ATCB_Key, To_Address (Self_Id));
73 pragma Assert (Result = 0);
80 -- To make Ada tasks and C threads interoperate better, we have added some
81 -- functionality to Self. Suppose a C main program (with threads) calls an
82 -- Ada procedure and the Ada procedure calls the tasking runtime system.
83 -- Eventually, a call will be made to self. Since the call is not coming
84 -- from an Ada task, there will be no corresponding ATCB.
86 -- What we do in Self is to catch references that do not come from
87 -- recognized Ada tasks, and create an ATCB for the calling thread.
89 -- The new ATCB will be "detached" from the normal Ada task master
90 -- hierarchy, much like the existing implicitly created signal-server
93 function Self return Task_Id is
94 Result : System.Address;
97 Result := pthread_getspecific (ATCB_Key);
99 -- If the key value is Null, then it is a non-Ada task.
101 if Result /= System.Null_Address then
102 return To_Task_Id (Result);
104 return Register_Foreign_Thread;