1------------------------------------------------------------------------------ 2-- -- 3-- GNU ADA RUN-TIME LIBRARY (GNARL) COMPONENTS -- 4-- -- 5-- SYSTEM.TASK_PRIMITIVES.OPERATIONS.SPECIFIC -- 6-- -- 7-- B o d y -- 8-- -- 9-- Copyright (C) 1992-2003, 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 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, 59 Temple Place - Suite 330, Boston, -- 20-- MA 02111-1307, USA. -- 21-- -- 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. -- 28-- -- 29-- GNARL was developed by the GNARL team at Florida State University. -- 30-- Extensive contributions were provided by Ada Core Technologies, Inc. -- 31-- -- 32------------------------------------------------------------------------------ 33 34-- This is a POSIX version of this package where foreign threads are 35-- recognized. 36 37-- Currently, DEC Unix, SCO UnixWare, Solaris pthread, HPUX pthread, 38-- GNU/Linux threads, and RTEMS use this version. 39 40separate (System.Task_Primitives.Operations) 41package body Specific is 42 43 ---------------- 44 -- Initialize -- 45 ---------------- 46 47 procedure Initialize (Environment_Task : Task_ID) is 48 pragma Warnings (Off, Environment_Task); 49 Result : Interfaces.C.int; 50 51 begin 52 Result := pthread_key_create (ATCB_Key'Access, null); 53 pragma Assert (Result = 0); 54 end Initialize; 55 56 ------------------- 57 -- Is_Valid_Task -- 58 ------------------- 59 60 function Is_Valid_Task return Boolean is 61 begin 62 return pthread_getspecific (ATCB_Key) /= System.Null_Address; 63 end Is_Valid_Task; 64 65 --------- 66 -- Set -- 67 --------- 68 69 procedure Set (Self_Id : Task_ID) is 70 Result : Interfaces.C.int; 71 begin 72 Result := pthread_setspecific (ATCB_Key, To_Address (Self_Id)); 73 pragma Assert (Result = 0); 74 end Set; 75 76 ---------- 77 -- Self -- 78 ---------- 79 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. 85 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. 88 89 -- The new ATCB will be "detached" from the normal Ada task master 90 -- hierarchy, much like the existing implicitly created signal-server 91 -- tasks. 92 93 function Self return Task_ID is 94 Result : System.Address; 95 96 begin 97 Result := pthread_getspecific (ATCB_Key); 98 99 -- If the key value is Null, then it is a non-Ada task. 100 101 if Result /= System.Null_Address then 102 return To_Task_Id (Result); 103 else 104 return Register_Foreign_Thread; 105 end if; 106 end Self; 107 108end Specific; 109