1------------------------------------------------------------------------------ 2-- -- 3-- GNAT RUN-TIME LIBRARY (GNARL) COMPONENTS -- 4-- -- 5-- SYSTEM.TASK_PRIMITIVES.OPERATIONS.SPECIFIC -- 6-- -- 7-- B o d y -- 8-- -- 9-- Copyright (C) 1992-2011, 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 is a VMS version of this package where foreign threads are 33-- recognized. 34 35separate (System.Task_Primitives.Operations) 36package body Specific is 37 38 ---------------- 39 -- Initialize -- 40 ---------------- 41 42 procedure Initialize (Environment_Task : Task_Id) is 43 pragma Warnings (Off, Environment_Task); 44 Result : Interfaces.C.int; 45 46 begin 47 Result := pthread_key_create (ATCB_Key'Access, null); 48 pragma Assert (Result = 0); 49 end Initialize; 50 51 ------------------- 52 -- Is_Valid_Task -- 53 ------------------- 54 55 function Is_Valid_Task return Boolean is 56 begin 57 return pthread_getspecific (ATCB_Key) /= System.Null_Address; 58 end Is_Valid_Task; 59 60 --------- 61 -- Set -- 62 --------- 63 64 procedure Set (Self_Id : Task_Id) is 65 Result : Interfaces.C.int; 66 begin 67 Result := pthread_setspecific (ATCB_Key, To_Address (Self_Id)); 68 pragma Assert (Result = 0); 69 end Set; 70 71 ---------- 72 -- Self -- 73 ---------- 74 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. 80 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. 83 84 -- The new ATCB will be "detached" from the normal Ada task master 85 -- hierarchy, much like the existing implicitly created signal-server 86 -- tasks. 87 88 function Self return Task_Id is 89 Result : System.Address; 90 91 begin 92 Result := pthread_getspecific (ATCB_Key); 93 94 -- If the key value is Null then it is a non-Ada task 95 96 if Result /= System.Null_Address then 97 return To_Task_Id (Result); 98 else 99 return Register_Foreign_Thread; 100 end if; 101 end Self; 102 103end Specific; 104