gcc/ada/g-thread.ads

   1 ------------------------------------------------------------------------------
   2 --                                                                          --
   3 --                         GNAT RUNTIME COMPONENTS                          --
   4 --                                                                          --
   5 --                         G N A T . T H R E A D S                          --
   6 --                                                                          --
   7 --                                 S p e c                                  --
   8 --                                                                          --
   9 --                                                                          --
  10 --           Copyright (C) 1998-2000 Ada Core Technologies, Inc.            --
  11 --                                                                          --
  12 -- GNAT is free software;  you can  redistribute it  and/or modify it under --
  13 -- terms of the  GNU General Public License as published  by the Free Soft- --
  14 -- ware  Foundation;  either version 2,  or (at your option) any later ver- --
  15 -- sion.  GNAT is distributed in the hope that it will be useful, but WITH- --
  16 -- OUT ANY WARRANTY;  without even the  implied warranty of MERCHANTABILITY --
  17 -- or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License --
  18 -- for  more details.  You should have  received  a copy of the GNU General --
  19 -- Public License  distributed with GNAT;  see file COPYING.  If not, write --
  20 -- to  the Free Software Foundation,  59 Temple Place - Suite 330,  Boston, --
  21 -- MA 02111-1307, USA.                                                      --
  22 --                                                                          --
  23 -- As a special exception,  if other files  instantiate  generics from this --
  24 -- unit, or you link  this unit with other files  to produce an executable, --
  25 -- this  unit  does not  by itself cause  the resulting  executable  to  be --
  26 -- covered  by the  GNU  General  Public  License.  This exception does not --
  27 -- however invalidate  any other reasons why  the executable file  might be --
  28 -- covered by the  GNU Public License.                                      --
  29 --                                                                          --
  30 -- GNAT is maintained by Ada Core Technologies Inc (http://www.gnat.com).   --
  31 --                                                                          --
  32 ------------------------------------------------------------------------------
  33
  34 --  This package provides facilities for creation of foreign threads for
  35 --  use as Ada tasks. In order to execute general Ada code, the run-time
  36 --  system must know about all tasks. This package allows foreign code,
  37 --  e.g. a C program, to create a thread that the Ada run-time knows about.
  38
  39 with System;
  40
  41 package GNAT.Threads is
  42
  43    type Void_Ptr is access all Integer;
  44
  45    function Create_Thread
  46      (Code : System.Address;  -- pointer
  47       Parm : Void_Ptr;        -- pointer
  48       Size : Natural;         -- int
  49       Prio : Integer)         -- int
  50       return System.Address;
  51    pragma Export (C, Create_Thread, "__gnat_create_thread");
  52    --  Creates a thread with the given (Size) stack size in bytes, and
  53    --  the given (Prio) priority. The task will execute a call to the
  54    --  procedure whose address is given by Code. This procedure has
  55    --  the prototype
  56    --
  57    --    void thread_code (void *id, void *parm);
  58    --
  59    --  where id is the id of the created task, and parm is the parameter
  60    --  passed to Create_Thread. The called procedure is the body of the
  61    --  code for the task, the task will be automatically terminated when
  62    --  the procedure returns.
  63    --
  64    --  This function returns the Ada Id of the created task that can then be
  65    --  used as a parameter to the procedures below.
  66    --
  67    --  C declaration:
  68    --
  69    --  extern void *__gnat_create_thread
  70    --    (void (*code)(void *, void *), void *parm, int size, int prio);
  71
  72    procedure Destroy_Thread (Id : System.Address);
  73    pragma Export (C, Destroy_Thread, "__gnat_destroy_thread");
  74    --  This procedure may be used to prematurely abort the created thread.
  75    --  The value Id is the value that was passed to the thread code procedure
  76    --  at activation time.
  77    --
  78    --  C declaration:
  79    --
  80    --  extern void __gnat_destroy_thread (void *id);
  81
  82    procedure Get_Thread (Id : System.Address; Thread : System.Address);
  83    pragma Export (C, Get_Thread, "__gnat_get_thread");
  84    --  This procedure is used to retrieve the thread id of a given task.
  85    --  The value Id is the value that was passed to the thread code procedure
  86    --  at activation time.
  87    --  Thread is a pointer to a thread id that will be updated by this
  88    --  procedure.
  89    --
  90    --  C declaration:
  91    --
  92    --  extern void __gnat_get_thread (void *id, pthread_t *thread);
  93
  94 end GNAT.Threads;