------------------------------------------------------------------------------
-- --
--- GNU ADA RUN-TIME LIBRARY (GNARL) COMPONENTS --
+-- GNAT RUN-TIME LIBRARY (GNARL) COMPONENTS --
-- --
--- SYSTEM.TASKING.PROTECTED_OBJECTS.SINGLE_ENTRY --
+-- SYSTEM.TASKING.PROTECTED_OBJECTS.SINGLE_ENTRY --
-- --
--- B o d y --
+-- B o d y --
-- --
--- Copyright (C) 1998-2004, Free Software Foundation, Inc. --
+-- Copyright (C) 1998-2009, Free Software Foundation, Inc. --
-- --
-- GNARL 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. GNARL is distributed in the hope that it will be useful, but WITH- --
+-- ware Foundation; either version 3, 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 GNARL; see file COPYING. If not, write --
--- to the Free Software Foundation, 59 Temple Place - Suite 330, Boston, --
--- MA 02111-1307, USA. --
+-- or FITNESS FOR A PARTICULAR PURPOSE. --
-- --
--- 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. --
+-- As a special exception under Section 7 of GPL version 3, you are granted --
+-- additional permissions described in the GCC Runtime Library Exception, --
+-- version 3.1, as published by the Free Software Foundation. --
+-- --
+-- You should have received a copy of the GNU General Public License and --
+-- a copy of the GCC Runtime Library Exception along with this program; --
+-- see the files COPYING3 and COPYING.RUNTIME respectively. If not, see --
+-- <http://www.gnu.org/licenses/>. --
-- --
-- GNARL was developed by the GNARL team at Florida State University. --
-- Extensive contributions were provided by Ada Core Technologies, Inc. --
------------------------------------------------------------------------------
pragma Style_Checks (All_Checks);
--- Turn off subprogram ordering check, since restricted GNARLI
--- subprograms are gathered together at end.
+-- Turn off subprogram ordering check, since restricted GNARLI subprograms are
+-- gathered together at end.
-- This package provides an optimized version of Protected_Objects.Operations
-- and Protected_Objects.Entries making the following assumptions:
---
--- PO have only one entry
--- There is only one caller at a time (No_Entry_Queue)
--- There is no dynamic priority support (No_Dynamic_Priorities)
--- No Abort Statements
--- (No_Abort_Statements, Max_Asynchronous_Select_Nesting => 0)
--- PO are at library level
--- No Requeue
--- None of the tasks will terminate (no need for finalization)
---
+
+-- PO has only one entry
+-- There is only one caller at a time (No_Entry_Queue)
+-- There is no dynamic priority support (No_Dynamic_Priorities)
+-- No Abort Statements
+-- (No_Abort_Statements, Max_Asynchronous_Select_Nesting => 0)
+-- PO are at library level
+-- No Requeue
+-- None of the tasks will terminate (no need for finalization)
+
-- This interface is intended to be used in the ravenscar and restricted
-- profiles, the compiler is responsible for ensuring that the conditions
-- mentioned above are respected, except for the No_Entry_Queue restriction
-- operations. It can cause infinite loops and other problems.
pragma Suppress (All_Checks);
-
-with System.Task_Primitives.Operations;
--- used for Self
--- Finalize_Lock
--- Write_Lock
--- Unlock
+-- Why is this required ???
with Ada.Exceptions;
--- used for Exception_Id
--- Raise_Exception
+with System.Task_Primitives.Operations;
with System.Parameters;
--- used for Single_Lock
package body System.Tasking.Protected_Objects.Single_Entry is
use type Ada.Exceptions.Exception_Id;
E : constant Ada.Exceptions.Exception_Id :=
- Entry_Call.Exception_To_Raise;
+ Entry_Call.Exception_To_Raise;
begin
if E /= Ada.Exceptions.Null_Id then
is
Self_Id : constant Task_Id := Entry_Call.Self;
Timedout : Boolean;
+
Yielded : Boolean;
+ pragma Unreferenced (Yielded);
use type Ada.Exceptions.Exception_Id;
STPO.Timed_Sleep
(Self_Id, Wakeup_Time, Mode, Entry_Caller_Sleep, Timedout, Yielded);
- if Timedout then
- Entry_Call.State := Cancelled;
- else
- Entry_Call.State := Done;
- end if;
-
+ Entry_Call.State := (if Timedout then Cancelled else Done);
Self_Id.Common.State := Runnable;
end Wait_For_Completion_With_Timeout;
Compiler_Info : System.Address;
Entry_Body : Entry_Body_Access)
is
- Init_Priority : Integer := Ceiling_Priority;
begin
- if Init_Priority = Unspecified_Priority then
- Init_Priority := System.Priority'Last;
- end if;
+ Initialize_Protection (Object.Common'Access, Ceiling_Priority);
- STPO.Initialize_Lock (Init_Priority, Object.L'Access);
- Object.Ceiling := System.Any_Priority (Init_Priority);
Object.Compiler_Info := Compiler_Info;
Object.Call_In_Progress := null;
Object.Entry_Body := Entry_Body;
-- Do not call this procedure from within the run-time system.
procedure Lock_Entry (Object : Protection_Entry_Access) is
- Ceiling_Violation : Boolean;
-
begin
- -- If pragma Detect_Blocking is active then Program_Error must
- -- be raised if this potentially blocking operation is called from
- -- a protected action, and the protected object nesting level
- -- must be increased.
-
- if Detect_Blocking then
- declare
- Self_Id : constant Task_Id := STPO.Self;
- begin
- if Self_Id.Common.Protected_Action_Nesting > 0 then
- Ada.Exceptions.Raise_Exception
- (Program_Error'Identity, "potentially blocking operation");
- else
- -- We are entering in a protected action, so that we
- -- increase the protected object nesting level.
-
- Self_Id.Common.Protected_Action_Nesting :=
- Self_Id.Common.Protected_Action_Nesting + 1;
- end if;
- end;
- end if;
-
- STPO.Write_Lock (Object.L'Access, Ceiling_Violation);
-
- if Ceiling_Violation then
- raise Program_Error;
- end if;
+ Lock (Object.Common'Access);
end Lock_Entry;
--------------------------
-- Lock_Read_Only_Entry --
--------------------------
- -- Compiler interface only.
- -- Do not call this procedure from within the runtime system.
+ -- Compiler interface only
- procedure Lock_Read_Only_Entry (Object : Protection_Entry_Access) is
- Ceiling_Violation : Boolean;
+ -- Do not call this procedure from within the runtime system
+ procedure Lock_Read_Only_Entry (Object : Protection_Entry_Access) is
begin
- -- If pragma Detect_Blocking is active then Program_Error must be
- -- raised if this potentially blocking operation is called from a
- -- protected action, and the protected object nesting level must
- -- be increased.
-
- if Detect_Blocking then
- declare
- Self_Id : constant Task_Id := STPO.Self;
- begin
- if Self_Id.Common.Protected_Action_Nesting > 0 then
- Ada.Exceptions.Raise_Exception
- (Program_Error'Identity, "potentially blocking operation");
- else
- -- We are entering in a protected action, so that we
- -- increase the protected object nesting level.
-
- Self_Id.Common.Protected_Action_Nesting :=
- Self_Id.Common.Protected_Action_Nesting + 1;
- end if;
- end;
- end if;
-
- STPO.Read_Lock (Object.L'Access, Ceiling_Violation);
-
- if Ceiling_Violation then
- raise Program_Error;
- end if;
+ Lock_Read_Only (Object.Common'Access);
end Lock_Read_Only_Entry;
--------------------
Entry_Call : Entry_Call_Link)
is
Barrier_Value : Boolean;
+
begin
-- When the Action procedure for an entry body returns, it must be
-- completed (having called [Exceptional_]Complete_Entry_Body).
if Barrier_Value then
if Object.Call_In_Progress /= null then
+
-- This violates the No_Entry_Queue restriction, send
-- Program_Error to the caller.
end if;
elsif Entry_Call.Mode /= Conditional_Call then
- Object.Entry_Queue := Entry_Call;
+ if Object.Entry_Queue /= null then
+
+ -- This violates the No_Entry_Queue restriction, send
+ -- Program_Error to the caller.
+
+ Send_Program_Error (Self_Id, Entry_Call);
+ return;
+ else
+ Object.Entry_Queue := Entry_Call;
+ end if;
+
else
-- Conditional_Call
Uninterpreted_Data : System.Address;
Mode : Call_Modes)
is
- Self_Id : constant Task_Id := STPO.Self;
- Entry_Call : Entry_Call_Record renames Self_Id.Entry_Calls (1);
- Ceiling_Violation : Boolean;
-
+ Self_Id : constant Task_Id := STPO.Self;
+ Entry_Call : Entry_Call_Record renames Self_Id.Entry_Calls (1);
begin
-- If pragma Detect_Blocking is active then Program_Error must be
-- raised if this potentially blocking operation is called from a
if Detect_Blocking
and then Self_Id.Common.Protected_Action_Nesting > 0
then
- Ada.Exceptions.Raise_Exception
- (Program_Error'Identity, "potentially blocking operation");
+ raise Program_Error with "potentially blocking operation";
end if;
- STPO.Write_Lock (Object.L'Access, Ceiling_Violation);
-
- if Ceiling_Violation then
- raise Program_Error;
- end if;
+ Lock_Entry (Object);
Entry_Call.Mode := Mode;
Entry_Call.State := Now_Abortable;
-- Timed_Protected_Single_Entry_Call --
---------------------------------------
- -- Compiler interface only. Do not call from within the RTS.
+ -- Compiler interface only (do not call from within the RTS)
procedure Timed_Protected_Single_Entry_Call
(Object : Protection_Entry_Access;
is
Self_Id : constant Task_Id := STPO.Self;
Entry_Call : Entry_Call_Record renames Self_Id.Entry_Calls (1);
- Ceiling_Violation : Boolean;
begin
-- If pragma Detect_Blocking is active then Program_Error must be
if Detect_Blocking
and then Self_Id.Common.Protected_Action_Nesting > 0
then
- Ada.Exceptions.Raise_Exception
- (Program_Error'Identity, "potentially blocking operation");
+ raise Program_Error with "potentially blocking operation";
end if;
- STPO.Write_Lock (Object.L'Access, Ceiling_Violation);
-
- if Ceiling_Violation then
- raise Program_Error;
- end if;
+ Lock (Object.Common'Access);
Entry_Call.Mode := Timed_Call;
Entry_Call.State := Now_Abortable;
procedure Unlock_Entry (Object : Protection_Entry_Access) is
begin
- -- We are exiting from a protected action, so that we decrease the
- -- protected object nesting level (if pragma Detect_Blocking is active).
-
- if Detect_Blocking then
- declare
- Self_Id : constant Task_Id := Self;
-
- begin
- -- Cannot call Unlock_Entry without being within protected action
-
- pragma Assert (Self_Id.Common.Protected_Action_Nesting > 0);
-
- Self_Id.Common.Protected_Action_Nesting :=
- Self_Id.Common.Protected_Action_Nesting - 1;
- end;
- end if;
-
- STPO.Unlock (Object.L'Access);
+ Unlock (Object.Common'Access);
end Unlock_Entry;
end System.Tasking.Protected_Objects.Single_Entry;