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diff --git a/gcc/ada/g-thread.ads b/gcc/ada/g-thread.ads new file mode 100644 index 000000000..b5825f39f --- /dev/null +++ b/gcc/ada/g-thread.ads @@ -0,0 +1,151 @@ +------------------------------------------------------------------------------ +-- -- +-- GNAT RUN-TIME COMPONENTS -- +-- -- +-- G N A T . T H R E A D S -- +-- -- +-- S p e c -- +-- -- +-- Copyright (C) 1998-2007, AdaCore -- +-- -- +-- GNAT is free software; you can redistribute it and/or modify it under -- +-- terms of the GNU General Public License as published by the Free Soft- -- +-- ware Foundation; either version 2, or (at your option) any later ver- -- +-- sion. GNAT is distributed in the hope that it will be useful, but WITH- -- +-- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY -- +-- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License -- +-- for more details. You should have received a copy of the GNU General -- +-- Public License distributed with GNAT; see file COPYING. If not, write -- +-- to the Free Software Foundation, 51 Franklin Street, Fifth Floor, -- +-- Boston, MA 02110-1301, USA. -- +-- -- +-- As a special exception, if other files instantiate generics from this -- +-- unit, or you link this unit with other files to produce an executable, -- +-- this unit does not by itself cause the resulting executable to be -- +-- covered by the GNU General Public License. This exception does not -- +-- however invalidate any other reasons why the executable file might be -- +-- covered by the GNU Public License. -- +-- -- +-- GNAT was originally developed by the GNAT team at New York University. -- +-- Extensive contributions were provided by Ada Core Technologies Inc. -- +-- -- +------------------------------------------------------------------------------ + +-- This package provides facilities for creation or registration of foreign +-- threads for use as Ada tasks. In order to execute general Ada code, the +-- run-time system must know about all tasks. This package allows foreign +-- code, e.g. a C program, to create a thread that the Ada run-time knows +-- about, or to register the current thread. + +-- For some implementations of GNAT Pro, the registration of foreign threads +-- is automatic. However, in such implementations, if the Ada program has no +-- tasks at all and no tasking constructs other than delay, then by default +-- the non-tasking version of the Ada run-time will be loaded. If foreign +-- threads are present, it is important to ensure that the tasking version +-- of the Ada run time is loaded. This may be achieved by adding "with +-- GNAT.Threads" to any unit in the partition. + +with System; +with Ada.Task_Identification; + +package GNAT.Threads is + + type Void_Ptr is access all Integer; + + function Create_Thread + (Code : System.Address; -- pointer + Parm : Void_Ptr; -- pointer + Size : Natural; -- int + Prio : Integer) -- int + return System.Address; + pragma Export (C, Create_Thread, "__gnat_create_thread"); + -- Creates a thread with the given (Size) stack size in bytes, and + -- the given (Prio) priority. The task will execute a call to the + -- procedure whose address is given by Code. This procedure has + -- the prototype + -- + -- void thread_code (void *id, void *parm); + -- + -- where id is the id of the created task, and parm is the parameter + -- passed to Create_Thread. The called procedure is the body of the + -- code for the task, the task will be automatically terminated when + -- the procedure returns. + -- + -- This function returns the Ada Id of the created task that can then be + -- used as a parameter to the procedures below. + -- + -- C declaration: + -- + -- extern void *__gnat_create_thread + -- (void (*code)(void *, void *), void *parm, int size, int prio); + + function Register_Thread return System.Address; + pragma Export (C, Register_Thread, "__gnat_register_thread"); + -- Create an Ada task Id for the current thread if needed. + -- If the thread could not be registered, System.Null_Address is returned. + -- + -- This function returns the Ada Id of the current task that can then be + -- used as a parameter to the procedures below. + -- + -- C declaration: + -- + -- extern void *__gnat_register_thread (); + -- + -- Here is a typical usage of the Register/Unregister_Thread procedures: + -- + -- void thread_body () + -- { + -- void *task_id = __gnat_register_thread (); + -- ... thread body ... + -- __gnat_unregister_thread (); + -- } + + procedure Unregister_Thread; + pragma Export (C, Unregister_Thread, "__gnat_unregister_thread"); + -- Unregister the current task from the GNAT run time and destroy the + -- memory allocated for its task id. + -- + -- C declaration: + -- + -- extern void __gnat_unregister_thread (); + + procedure Unregister_Thread_Id (Thread : System.Address); + pragma Export (C, Unregister_Thread_Id, "__gnat_unregister_thread_id"); + -- Unregister the task associated with Thread from the GNAT run time and + -- destroy the memory allocated for its task id. + -- If no task id is associated with Thread, do nothing. + -- + -- C declaration: + -- + -- extern void __gnat_unregister_thread_id (pthread_t *thread); + + procedure Destroy_Thread (Id : System.Address); + pragma Export (C, Destroy_Thread, "__gnat_destroy_thread"); + -- This procedure may be used to prematurely abort the created thread. + -- The value Id is the value that was passed to the thread code procedure + -- at activation time. + -- + -- C declaration: + -- + -- extern void __gnat_destroy_thread (void *id); + + procedure Get_Thread (Id : System.Address; Thread : System.Address); + pragma Export (C, Get_Thread, "__gnat_get_thread"); + -- This procedure is used to retrieve the thread id of a given task. + -- The value Id is the value that was passed to the thread code procedure + -- at activation time. + -- Thread is a pointer to a thread id that will be updated by this + -- procedure. + -- + -- C declaration: + -- + -- extern void __gnat_get_thread (void *id, pthread_t *thread); + + function To_Task_Id + (Id : System.Address) + return Ada.Task_Identification.Task_Id; + -- Ada interface only. + -- Given a low level Id, as returned by Create_Thread, return a Task_Id, + -- so that operations in Ada.Task_Identification can be used. + +end GNAT.Threads; |