gcc/ada/s-solita.adb

   1 ------------------------------------------------------------------------------
   2 --                                                                          --
   3 --                         GNAT COMPILER COMPONENTS                         --
   4 --                                                                          --
   5 --             S Y S T E M . S O F T _ L I N K S . T A S K I N G            --
   6 --                                                                          --
   7 --                                 B o d y                                  --
   8 --                                                                          --
   9 --             Copyright (C) 2004, Free Software Foundation, Inc.           --
  10 --                                                                          --
  11 -- GNAT 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.  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.  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 GNAT;  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 -- GNAT was originally developed  by the GNAT team at  New York University. --
  30 -- Extensive contributions were provided by Ada Core Technologies Inc.      --
  31 --                                                                          --
  32 ------------------------------------------------------------------------------
  33
  34 pragma Style_Checks (All_Checks);
  35 --  Turn off subprogram alpha ordering check, since we group soft link
  36 --  bodies and dummy soft link bodies together separately in this unit.
  37
  38 pragma Polling (Off);
  39 --  Turn polling off for this package. We don't need polling during any
  40 --  of the routines in this package, and more to the point, if we try
  41 --  to poll it can cause infinite loops.
  42
  43 with System.Task_Primitives.Operations;
  44 --  Used for Self
  45 --           Timed_Delay
  46
  47 with System.Tasking;
  48 --  Used for Task_Id
  49
  50 with Ada.Exceptions;
  51 --  Used for Raise_Exception
  52
  53 package body System.Soft_Links.Tasking is
  54
  55    package STPO renames System.Task_Primitives.Operations;
  56    package SSL  renames System.Soft_Links;
  57
  58    ----------------
  59    -- Local Data --
  60    ----------------
  61
  62    Initialized : Boolean := False;
  63    --  Boolean flag that indicates whether the tasking soft links have
  64    --  already been set.
  65
  66    -----------------------------------------------------------------
  67    -- Tasking Versions of Services Needed by Non-Tasking Programs --
  68    -----------------------------------------------------------------
  69
  70    function  Get_Jmpbuf_Address return  Address;
  71    procedure Set_Jmpbuf_Address (Addr : Address);
  72    --  Get/Set Jmpbuf_Address for current task
  73
  74    function  Get_Sec_Stack_Addr return  Address;
  75    procedure Set_Sec_Stack_Addr (Addr : Address);
  76    --  Get/Set location of current task's secondary stack
  77
  78    function  Get_Machine_State_Addr return Address;
  79    procedure Set_Machine_State_Addr (Addr : Address);
  80    --  Get/Set the address for storing the current task's machine state
  81
  82    function Get_Current_Excep return SSL.EOA;
  83    --  Task-safe version of SSL.Get_Current_Excep
  84
  85    procedure Timed_Delay_T (Time : Duration; Mode : Integer);
  86    --  Task-safe version of SSL.Timed_Delay
  87
  88    --------------------------
  89    -- Soft-Link Get Bodies --
  90    --------------------------
  91
  92    function Get_Current_Excep return SSL.EOA is
  93    begin
  94       return STPO.Self.Common.Compiler_Data.Current_Excep'Access;
  95    end Get_Current_Excep;
  96
  97    function Get_Jmpbuf_Address return  Address is
  98    begin
  99       return STPO.Self.Common.Compiler_Data.Jmpbuf_Address;
 100    end Get_Jmpbuf_Address;
 101
 102    function Get_Machine_State_Addr return Address is
 103    begin
 104       return STPO.Self.Common.Compiler_Data.Machine_State_Addr;
 105    end Get_Machine_State_Addr;
 106
 107    function Get_Sec_Stack_Addr return  Address is
 108    begin
 109       return STPO.Self.Common.Compiler_Data.Sec_Stack_Addr;
 110    end Get_Sec_Stack_Addr;
 111
 112    --------------------------
 113    -- Soft-Link Set Bodies --
 114    --------------------------
 115
 116    procedure Set_Jmpbuf_Address (Addr : Address) is
 117    begin
 118       STPO.Self.Common.Compiler_Data.Jmpbuf_Address := Addr;
 119    end Set_Jmpbuf_Address;
 120
 121    procedure Set_Machine_State_Addr (Addr : Address) is
 122    begin
 123       STPO.Self.Common.Compiler_Data.Machine_State_Addr := Addr;
 124    end Set_Machine_State_Addr;
 125
 126    procedure Set_Sec_Stack_Addr (Addr : Address) is
 127    begin
 128       STPO.Self.Common.Compiler_Data.Sec_Stack_Addr := Addr;
 129    end Set_Sec_Stack_Addr;
 130
 131    -------------------
 132    -- Timed_Delay_T --
 133    -------------------
 134
 135    procedure Timed_Delay_T (Time : Duration; Mode : Integer) is
 136       Self_Id : constant System.Tasking.Task_Id := STPO.Self;
 137
 138    begin
 139       --  In case pragma Detect_Blocking is active then Program_Error
 140       --  must be raised if this potentially blocking operation
 141       --  is called from a protected operation.
 142
 143       if System.Tasking.Detect_Blocking
 144         and then Self_Id.Common.Protected_Action_Nesting > 0
 145       then
 146          Ada.Exceptions.Raise_Exception
 147            (Program_Error'Identity, "potentially blocking operation");
 148       else
 149          STPO.Timed_Delay (Self_Id, Time, Mode);
 150       end if;
 151
 152    end Timed_Delay_T;
 153
 154    -----------------------------
 155    -- Init_Tasking_Soft_Links --
 156    -----------------------------
 157
 158    procedure Init_Tasking_Soft_Links is
 159    begin
 160       --  Set links only if not set already
 161
 162       if not Initialized then
 163
 164          --  Mark tasking soft links as initialized
 165
 166          Initialized := True;
 167
 168          --  The application being executed uses tasking so that the tasking
 169          --  version of the following soft links need to be used.
 170
 171          SSL.Get_Jmpbuf_Address     := Get_Jmpbuf_Address'Access;
 172          SSL.Set_Jmpbuf_Address     := Set_Jmpbuf_Address'Access;
 173          SSL.Get_Sec_Stack_Addr     := Get_Sec_Stack_Addr'Access;
 174          SSL.Set_Sec_Stack_Addr     := Set_Sec_Stack_Addr'Access;
 175          SSL.Get_Machine_State_Addr := Get_Machine_State_Addr'Access;
 176          SSL.Set_Machine_State_Addr := Set_Machine_State_Addr'Access;
 177          SSL.Get_Current_Excep      := Get_Current_Excep'Access;
 178          SSL.Timed_Delay            := Timed_Delay_T'Access;
 179
 180          --  No need to create a new Secondary Stack, since we will use the
 181          --  default one created in s-secsta.adb
 182
 183          SSL.Set_Sec_Stack_Addr     (SSL.Get_Sec_Stack_Addr_NT);
 184          SSL.Set_Jmpbuf_Address     (SSL.Get_Jmpbuf_Address_NT);
 185          SSL.Set_Machine_State_Addr (SSL.Get_Machine_State_Addr_NT);
 186       end if;
 187    end Init_Tasking_Soft_Links;
 188
 189 end System.Soft_Links.Tasking;