blob: 4f9d314d000dddc88fdc59d9659233368bdc1c1d [file] [log] [blame]
------------------------------------------------------------------------------
-- --
-- GNAT COMPILER COMPONENTS --
-- --
-- S Y S T E M . R P C --
-- --
-- B o d y --
-- --
-- $Revision: 1.1 $ --
-- --
-- Copyright (C) 1992,1993,1994,1995 Free Software Foundation, Inc. --
-- --
-- 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, 59 Temple Place - Suite 330, Boston, --
-- MA 02111-1307, 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. --
-- It is now maintained by Ada Core Technologies Inc (http://www.gnat.com). --
-- --
------------------------------------------------------------------------------
with Unchecked_Deallocation;
with Ada.Streams;
with System.RPC.Net_Trace;
with System.RPC.Garlic;
with System.RPC.Streams;
pragma Elaborate (System.RPC.Garlic);
package body System.RPC is
use type Ada.Streams.Stream_Element_Count;
use type Ada.Streams.Stream_Element_Offset;
use type Garlic.Protocol_Access;
use type Garlic.Lock_Method;
Max_Of_Message_Id : constant := 127;
subtype Message_Id_Type is
Integer range -Max_Of_Message_Id .. Max_Of_Message_Id;
-- A message id is either a request id or reply id. A message id is
-- provided with a message to a receiving stub which uses the opposite
-- as a reply id. A message id helps to retrieve to which task is
-- addressed a reply. When the environment task receives a message, the
-- message id is extracted : a positive message id stands for a call, a
-- negative message id stands for a reply. A null message id stands for
-- an asynchronous request.
subtype Request_Id_Type is Message_Id_Type range 1 .. Max_Of_Message_Id;
-- When a message id is positive, it is a request
type Message_Length_Per_Request is array (Request_Id_Type)
of Ada.Streams.Stream_Element_Count;
Header_Size : Ada.Streams.Stream_Element_Count
:= Streams.Get_Integer_Initial_Size +
Streams.Get_SEC_Initial_Size;
-- Initial size needed for frequently used header streams
Stream_Error : exception;
-- Occurs when a read procedure is executed on an empty stream
-- or when a write procedure is executed on a full stream
Partition_RPC_Receiver : RPC_Receiver;
-- Cache the RPC_Recevier passed by Establish_RPC_Receiver
type Anonymous_Task_Node;
type Anonymous_Task_Node_Access is access Anonymous_Task_Node;
-- Types we need to construct a singly linked list of anonymous tasks
-- This pool is maintained to avoid a task creation each time a RPC
-- occurs - to be cont'd
task type Anonymous_Task_Type (Self : Anonymous_Task_Node_Access) is
entry Start
(Message_Id : in Message_Id_Type;
Partition : in Partition_ID;
Params_Size : in Ada.Streams.Stream_Element_Count;
Result_Size : in Ada.Streams.Stream_Element_Count;
Protocol : in Garlic.Protocol_Access);
-- This entry provides an anonymous task a remote call to perform
-- This task calls for a
-- Request id is provided to construct the reply id by using
-- -Request. Partition is used to send the reply message. Params_Size
-- is the size of the calling stub Params stream. Then, Protocol
-- (used by the environment task previously) allows to extract the
-- message following the header (The header is extracted by the
-- environment task)
end Anonymous_Task_Type;
type Anonymous_Task_Access is access Anonymous_Task_Type;
type Anonymous_Task_List is
record
Head : Anonymous_Task_Node_Access;
Tail : Anonymous_Task_Node_Access;
end record;
type Anonymous_Task_Node is
record
Element : Anonymous_Task_Access;
Next : Anonymous_Task_Node_Access;
end record;
-- Types we need to construct a singly linked list of anonymous tasks
-- This pool is maintained to avoid a task creation each time a RPC
-- occurs
protected Garbage_Collector is
procedure Allocate
(Item : out Anonymous_Task_Node_Access);
-- Anonymous task pool management : if there is an anonymous task
-- left, use it. Otherwise, allocate a new one
procedure Deallocate
(Item : in out Anonymous_Task_Node_Access);
-- Anonymous task pool management : queue this task in the pool
-- of inactive anonymous tasks.
private
Anonymous_List : Anonymous_Task_Node_Access;
-- The list root of inactive anonymous tasks
end Garbage_Collector;
task Dispatcher is
entry New_Request (Request : out Request_Id_Type);
-- To get a new request
entry Wait_On (Request_Id_Type)
(Length : out Ada.Streams.Stream_Element_Count);
-- To block the calling stub when it waits for a reply
-- When it is resumed, we provide the size of the reply
entry Wake_Up
(Request : in Request_Id_Type;
Length : in Ada.Streams.Stream_Element_Count);
-- To wake up the calling stub when the environnement task has
-- received a reply for this request
end Dispatcher;
task Environnement is
entry Start;
-- Receive no message until Partition_Receiver is set
-- Establish_RPC_Receiver decides when the environment task
-- is allowed to start
end Environnement;
protected Partition_Receiver is
entry Is_Set;
-- Blocks if the Partition_RPC_Receiver has not been set
procedure Set;
-- Done by Establish_RPC_Receiver when Partition_RPC_Receiver
-- is known
private
Was_Set : Boolean := False;
-- True when Partition_RPC_Receiver has been set
end Partition_Receiver;
-- Anonymous tasks have to wait for the Partition_RPC_Receiver
-- to be established
type Debug_Level is
(D_Elaborate, -- About the elaboration of this package
D_Communication, -- About calls to Send and Receive
D_Debug, -- Verbose
D_Exception); -- Exception handler
-- Debugging levels
package Debugging is new System.RPC.Net_Trace (Debug_Level, "RPC : ");
-- Debugging package
procedure D
(Flag : in Debug_Level; Info : in String) renames Debugging.Debug;
-- Shortcut
------------------------
-- Partition_Receiver --
------------------------
protected body Partition_Receiver is
-------------------------------
-- Partition_Receiver.Is_Set --
-------------------------------
entry Is_Set when Was_Set is
begin
null;
end Is_Set;
----------------------------
-- Partition_Receiver.Set --
----------------------------
procedure Set is
begin
Was_Set := True;
end Set;
end Partition_Receiver;
---------------
-- Head_Node --
---------------
procedure Head_Node
(Index : out Packet_Node_Access;
Stream : in Params_Stream_Type) is
begin
Index := Stream.Extra.Head;
exception when others =>
D (D_Exception, "exception in Head_Node");
raise;
end Head_Node;
---------------
-- Tail_Node --
---------------
procedure Tail_Node
(Index : out Packet_Node_Access;
Stream : in Params_Stream_Type) is
begin
Index := Stream.Extra.Tail;
exception when others =>
D (D_Exception, "exception in Tail_Node");
raise;
end Tail_Node;
---------------
-- Null_Node --
---------------
function Null_Node
(Index : in Packet_Node_Access) return Boolean is
begin
return Index = null;
exception when others =>
D (D_Exception, "exception in Null_Node");
raise;
end Null_Node;
----------------------
-- Delete_Head_Node --
----------------------
procedure Delete_Head_Node
(Stream : in out Params_Stream_Type) is
procedure Free is
new Unchecked_Deallocation
(Packet_Node, Packet_Node_Access);
Next_Node : Packet_Node_Access := Stream.Extra.Head.Next;
begin
-- Delete head node and free memory usage
Free (Stream.Extra.Head);
Stream.Extra.Head := Next_Node;
-- If the extra storage is empty, update tail as well
if Stream.Extra.Head = null then
Stream.Extra.Tail := null;
end if;
exception when others =>
D (D_Exception, "exception in Delete_Head_Node");
raise;
end Delete_Head_Node;
---------------
-- Next_Node --
---------------
procedure Next_Node
(Node : in out Packet_Node_Access) is
begin
-- Node is set to the next node
-- If not possible, Stream_Error is raised
if Node = null then
raise Stream_Error;
else
Node := Node.Next;
end if;
exception when others =>
D (D_Exception, "exception in Next_Node");
raise;
end Next_Node;
---------------------
-- Append_New_Node --
---------------------
procedure Append_New_Node
(Stream : in out Params_Stream_Type) is
Index : Packet_Node_Access;
begin
-- Set Index to the end of the linked list
Tail_Node (Index, Stream);
if Null_Node (Index) then
-- The list is empty : set head as well
Stream.Extra.Head := new Packet_Node;
Stream.Extra.Tail := Stream.Extra.Head;
else
-- The list is not empty : link new node with tail
Stream.Extra.Tail.Next := new Packet_Node;
Stream.Extra.Tail := Stream.Extra.Tail.Next;
end if;
exception when others =>
D (D_Exception, "exception in Append_New_Node");
raise;
end Append_New_Node;
----------
-- Read --
----------
procedure Read
(Stream : in out Params_Stream_Type;
Item : out Ada.Streams.Stream_Element_Array;
Last : out Ada.Streams.Stream_Element_Offset) renames
System.RPC.Streams.Read;
-----------
-- Write --
-----------
procedure Write
(Stream : in out Params_Stream_Type;
Item : in Ada.Streams.Stream_Element_Array) renames
System.RPC.Streams.Write;
-----------------------
-- Garbage_Collector --
-----------------------
protected body Garbage_Collector is
--------------------------------
-- Garbage_Collector.Allocate --
--------------------------------
procedure Allocate
(Item : out Anonymous_Task_Node_Access) is
New_Anonymous_Task_Node : Anonymous_Task_Node_Access;
Anonymous_Task : Anonymous_Task_Access;
begin
-- If the list is empty, allocate a new anonymous task
-- Otherwise, reuse the first queued anonymous task
if Anonymous_List = null then
-- Create a new anonymous task
-- Provide this new task with its id to allow it
-- to enqueue itself into the free anonymous task list
-- with the function Deallocate
New_Anonymous_Task_Node := new Anonymous_Task_Node;
Anonymous_Task :=
new Anonymous_Task_Type (New_Anonymous_Task_Node);
New_Anonymous_Task_Node.all := (Anonymous_Task, null);
else
-- Extract one task from the list
-- Set the Next field to null to avoid possible bugs
New_Anonymous_Task_Node := Anonymous_List;
Anonymous_List := Anonymous_List.Next;
New_Anonymous_Task_Node.Next := null;
end if;
-- Item is an out parameter
Item := New_Anonymous_Task_Node;
exception when others =>
D (D_Exception, "exception in Allocate (Anonymous Task)");
raise;
end Allocate;
----------------------------------
-- Garbage_Collector.Deallocate --
----------------------------------
procedure Deallocate
(Item : in out Anonymous_Task_Node_Access) is
begin
-- Enqueue the task in the free list
Item.Next := Anonymous_List;
Anonymous_List := Item;
exception when others =>
D (D_Exception, "exception in Deallocate (Anonymous Task)");
raise;
end Deallocate;
end Garbage_Collector;
------------
-- Do_RPC --
------------
procedure Do_RPC
(Partition : in Partition_ID;
Params : access Params_Stream_Type;
Result : access Params_Stream_Type) is
Protocol : Protocol_Access;
Request : Request_Id_Type;
Header : aliased Params_Stream_Type (Header_Size);
R_Length : Ada.Streams.Stream_Element_Count;
begin
-- Parameters order :
-- Opcode (provided and used by garlic)
-- (1) Size (provided by s-rpc and used by garlic)
-- (size of (2)+(3)+(4)+(5))
-- (2) Request (provided by calling stub (resp receiving stub) and
-- used by anonymous task (resp Do_RPC))
-- *** ZERO IF APC ***
-- (3) Res.len. (provided by calling stubs and used by anonymous task)
-- *** ZERO IF APC ***
-- (4) Receiver (provided by calling stubs and used by anonymous task)
-- (5) Params (provided by calling stubs and used by anonymous task)
-- The call is a remote call or a local call. A local call occurs
-- when the pragma All_Calls_Remote has been specified. Do_RPC is
-- called and the execution has to be performed in the PCS
if Partition /= Garlic.Get_My_Partition_ID then
-- Get a request id to be resumed when the reply arrives
Dispatcher.New_Request (Request);
-- Build header = request (2) + result.initial_size (3)
D (D_Debug, "Do_RPC - Build header");
Streams.Allocate (Header);
Streams.Integer_Write_Attribute -- (2)
(Header'Access, Request);
System.RPC.Streams.SEC_Write_Attribute -- (3)
(Header'Access, Result.Initial_Size);
-- Get a protocol method to communicate with the remote partition
-- and give the message size
D (D_Communication,
"Do_RPC - Lookup for protocol to talk to partition" &
Partition_ID'Image (Partition));
Garlic.Initiate_Send
(Partition,
Streams.Get_Stream_Size (Header'Access) +
Streams.Get_Stream_Size (Params), -- (1)
Protocol,
Garlic.Remote_Call);
-- Send the header by using the protocol method
D (D_Communication, "Do_RPC - Send Header to partition" &
Partition_ID'Image (Partition));
Garlic.Send
(Protocol.all,
Partition,
Header'Access); -- (2) + (3)
-- The header is deallocated
Streams.Deallocate (Header);
-- Send Params from Do_RPC
D (D_Communication, "Do_RPC - Send Params to partition" &
Partition_ID'Image (Partition));
Garlic.Send
(Protocol.all,
Partition,
Params); -- (4) + (5)
-- Let Garlic know we have nothing else to send
Garlic.Complete_Send
(Protocol.all,
Partition);
D (D_Debug, "Do_RPC - Suspend");
-- Wait for a reply and get the reply message length
Dispatcher.Wait_On (Request) (R_Length);
D (D_Debug, "Do_RPC - Resume");
declare
New_Result : aliased Params_Stream_Type (R_Length);
begin
-- Adjust the Result stream size right now to be able to load
-- the stream in one receive call. Create a temporary resutl
-- that will be substituted to Do_RPC one
Streams.Allocate (New_Result);
-- Receive the reply message from receiving stub
D (D_Communication, "Do_RPC - Receive Result from partition" &
Partition_ID'Image (Partition));
Garlic.Receive
(Protocol.all,
Partition,
New_Result'Access);
-- Let Garlic know we have nothing else to receive
Garlic.Complete_Receive
(Protocol.all,
Partition);
-- Update calling stub Result stream
D (D_Debug, "Do_RPC - Reconstruct Result");
Streams.Deallocate (Result.all);
Result.Initial := New_Result.Initial;
Streams.Dump ("|||", Result.all);
end;
else
-- Do RPC locally and first wait for Partition_RPC_Receiver to be
-- set
Partition_Receiver.Is_Set;
D (D_Debug, "Do_RPC - Locally");
Partition_RPC_Receiver.all (Params, Result);
end if;
exception when others =>
D (D_Exception, "exception in Do_RPC");
raise;
end Do_RPC;
------------
-- Do_APC --
------------
procedure Do_APC
(Partition : in Partition_ID;
Params : access Params_Stream_Type) is
Message_Id : Message_Id_Type := 0;
Protocol : Protocol_Access;
Header : aliased Params_Stream_Type (Header_Size);
begin
-- For more informations, see above
-- Request = 0 as we are not waiting for a reply message
-- Result length = 0 as we don't expect a result at all
if Partition /= Garlic.Get_My_Partition_ID then
-- Build header = request (2) + result.initial_size (3)
-- As we have an APC, the request id is null to indicate
-- to the receiving stub that we do not expect a reply
-- This comes from 0 = -0
D (D_Debug, "Do_APC - Build Header");
Streams.Allocate (Header);
Streams.Integer_Write_Attribute
(Header'Access, Integer (Message_Id));
Streams.SEC_Write_Attribute
(Header'Access, 0);
-- Get a protocol method to communicate with the remote partition
-- and give the message size
D (D_Communication,
"Do_APC - Lookup for protocol to talk to partition" &
Partition_ID'Image (Partition));
Garlic.Initiate_Send
(Partition,
Streams.Get_Stream_Size (Header'Access) +
Streams.Get_Stream_Size (Params),
Protocol,
Garlic.Remote_Call);
-- Send the header by using the protocol method
D (D_Communication, "Do_APC - Send Header to partition" &
Partition_ID'Image (Partition));
Garlic.Send
(Protocol.all,
Partition,
Header'Access);
-- The header is deallocated
Streams.Deallocate (Header);
-- Send Params from Do_APC
D (D_Communication, "Do_APC - Send Params to partition" &
Partition_ID'Image (Partition));
Garlic.Send
(Protocol.all,
Partition,
Params);
-- Let Garlic know we have nothing else to send
Garlic.Complete_Send
(Protocol.all,
Partition);
else
declare
Result : aliased Params_Stream_Type (0);
begin
-- Result is here a dummy parameter
-- No reason to deallocate as it is not allocated at all
Partition_Receiver.Is_Set;
D (D_Debug, "Do_APC - Locally");
Partition_RPC_Receiver.all (Params, Result'Access);
end;
end if;
exception when others =>
D (D_Exception, "exception in Do_APC");
raise;
end Do_APC;
----------------------------
-- Establish_RPC_Receiver --
----------------------------
procedure Establish_RPC_Receiver (
Partition : in Partition_ID;
Receiver : in RPC_Receiver) is
begin
-- Set Partition_RPC_Receiver and allow RPC mechanism
Partition_RPC_Receiver := Receiver;
Partition_Receiver.Set;
D (D_Elaborate, "Partition_Receiver is set");
exception when others =>
D (D_Exception, "exception in Establish_RPC_Receiver");
raise;
end Establish_RPC_Receiver;
----------------
-- Dispatcher --
----------------
task body Dispatcher is
Last_Request : Request_Id_Type := Request_Id_Type'First;
Current_Rqst : Request_Id_Type := Request_Id_Type'First;
Current_Size : Ada.Streams.Stream_Element_Count;
begin
loop
-- Three services :
-- New_Request to get an entry in Dispatcher table
-- Wait_On for Do_RPC calls
-- Wake_Up called by environment task when a Do_RPC receives
-- the result of its remote call
select
accept New_Request
(Request : out Request_Id_Type) do
Request := Last_Request;
-- << TODO >>
-- Avaibility check
if Last_Request = Request_Id_Type'Last then
Last_Request := Request_Id_Type'First;
else
Last_Request := Last_Request + 1;
end if;
end New_Request;
or
accept Wake_Up
(Request : in Request_Id_Type;
Length : in Ada.Streams.Stream_Element_Count) do
-- The environment reads the header and has been notified
-- of the reply id and the size of the result message
Current_Rqst := Request;
Current_Size := Length;
end Wake_Up;
-- << TODO >>
-- Must be select with delay for aborted tasks
select
accept Wait_On (Current_Rqst)
(Length : out Ada.Streams.Stream_Element_Count) do
Length := Current_Size;
end Wait_On;
or
-- To free the Dispatcher when a task is aborted
delay 1.0;
end select;
or
terminate;
end select;
end loop;
exception when others =>
D (D_Exception, "exception in Dispatcher body");
raise;
end Dispatcher;
-------------------------
-- Anonymous_Task_Type --
-------------------------
task body Anonymous_Task_Type is
Whoami : Anonymous_Task_Node_Access := Self;
C_Message_Id : Message_Id_Type; -- Current Message Id
C_Partition : Partition_ID; -- Current Partition
Params_S : Ada.Streams.Stream_Element_Count; -- Params message size
Result_S : Ada.Streams.Stream_Element_Count; -- Result message size
C_Protocol : Protocol_Access; -- Current Protocol
begin
loop
-- Get a new RPC to execute
select
accept Start
(Message_Id : in Message_Id_Type;
Partition : in Partition_ID;
Params_Size : in Ada.Streams.Stream_Element_Count;
Result_Size : in Ada.Streams.Stream_Element_Count;
Protocol : in Protocol_Access) do
C_Message_Id := Message_Id;
C_Partition := Partition;
Params_S := Params_Size;
Result_S := Result_Size;
C_Protocol := Protocol;
end Start;
or
terminate;
end select;
declare
Params : aliased Params_Stream_Type (Params_S);
Result : aliased Params_Stream_Type (Result_S);
Header : aliased Params_Stream_Type (Header_Size);
begin
-- We reconstruct all the client context : Params and Result
-- with the SAME size, then we receive Params from calling stub
D (D_Communication,
"Anonymous Task - Receive Params from partition" &
Partition_ID'Image (C_Partition));
Garlic.Receive
(C_Protocol.all,
C_Partition,
Params'Access);
-- Let Garlic know we don't receive anymore
Garlic.Complete_Receive
(C_Protocol.all,
C_Partition);
-- Check that Partition_RPC_Receiver has been set
Partition_Receiver.Is_Set;
-- Do it locally
D (D_Debug,
"Anonymous Task - Perform Partition_RPC_Receiver for request" &
Message_Id_Type'Image (C_Message_Id));
Partition_RPC_Receiver (Params'Access, Result'Access);
-- If this was a RPC we send the result back
-- Otherwise, do nothing else than deallocation
if C_Message_Id /= 0 then
-- Build Header = -C_Message_Id + Result Size
-- Provide the request id to the env task of the calling
-- stub partition We get the real result stream size : the
-- calling stub (in Do_RPC) updates its size to this one
D (D_Debug, "Anonymous Task - Build Header");
Streams.Allocate (Header);
Streams.Integer_Write_Attribute
(Header'Access, Integer (-C_Message_Id));
Streams.SEC_Write_Attribute
(Header'Access,
Streams.Get_Stream_Size (Result'Access));
-- Get a protocol method to comunicate with the remote
-- partition and give the message size
D (D_Communication,
"Anonymous Task - Lookup for protocol talk to partition" &
Partition_ID'Image (C_Partition));
Garlic.Initiate_Send
(C_Partition,
Streams.Get_Stream_Size (Header'Access) +
Streams.Get_Stream_Size (Result'Access),
C_Protocol,
Garlic.Remote_Call);
-- Send the header by using the protocol method
D (D_Communication,
"Anonymous Task - Send Header to partition" &
Partition_ID'Image (C_Partition));
Garlic.Send
(C_Protocol.all,
C_Partition,
Header'Access);
-- Send Result toDo_RPC
D (D_Communication,
"Anonymous Task - Send Result to partition" &
Partition_ID'Image (C_Partition));
Garlic.Send
(C_Protocol.all,
C_Partition,
Result'Access);
-- Let Garlic know we don't send anymore
Garlic.Complete_Send
(C_Protocol.all,
C_Partition);
Streams.Deallocate (Header);
end if;
Streams.Deallocate (Params);
Streams.Deallocate (Result);
end;
-- Enqueue into the anonymous task free list : become inactive
Garbage_Collector.Deallocate (Whoami);
end loop;
exception when others =>
D (D_Exception, "exception in Anonymous_Task_Type body");
raise;
end Anonymous_Task_Type;
-----------------
-- Environment --
-----------------
task body Environnement is
Partition : Partition_ID;
Message_Size : Ada.Streams.Stream_Element_Count;
Result_Size : Ada.Streams.Stream_Element_Count;
Message_Id : Message_Id_Type;
Header : aliased Params_Stream_Type (Header_Size);
Protocol : Protocol_Access;
Anonymous : Anonymous_Task_Node_Access;
begin
-- Wait the Partition_RPC_Receiver to be set
accept Start;
D (D_Elaborate, "Environment task elaborated");
loop
-- We receive first a fixed size message : the header
-- Header = Message Id + Message Size
Streams.Allocate (Header);
-- Garlic provides the size of the received message and the
-- protocol to use to communicate with the calling partition
Garlic.Initiate_Receive
(Partition,
Message_Size,
Protocol,
Garlic.Remote_Call);
D (D_Communication,
"Environment task - Receive protocol to talk to active partition" &
Partition_ID'Image (Partition));
-- Extract the header to route the message either to
-- an anonymous task (Message Id > 0 <=> Request Id)
-- or to a waiting task (Message Id < 0 <=> Reply Id)
D (D_Communication,
"Environment task - Receive Header from partition" &
Partition_ID'Image (Partition));
Garlic.Receive
(Protocol.all,
Partition,
Header'Access);
-- Evaluate the remaining size of the message
Message_Size := Message_Size -
Streams.Get_Stream_Size (Header'Access);
-- Extract from header : message id and message size
Streams.Integer_Read_Attribute (Header'Access, Message_Id);
Streams.SEC_Read_Attribute (Header'Access, Result_Size);
if Streams.Get_Stream_Size (Header'Access) /= 0 then
-- If there are stream elements left in the header ???
D (D_Exception, "Header is not empty");
raise Program_Error;
end if;
if Message_Id < 0 then
-- The message was sent by a receiving stub : wake up the
-- calling task - We have a reply there
D (D_Debug, "Environment Task - Receive Reply from partition" &
Partition_ID'Image (Partition));
Dispatcher.Wake_Up (-Message_Id, Result_Size);
else
-- The message was send by a calling stub : get an anonymous
-- task to perform the job
D (D_Debug, "Environment Task - Receive Request from partition" &
Partition_ID'Image (Partition));
Garbage_Collector.Allocate (Anonymous);
-- We subtracted the size of the header from the size of the
-- global message in order to provide immediatly Params size
Anonymous.Element.Start
(Message_Id,
Partition,
Message_Size,
Result_Size,
Protocol);
end if;
-- Deallocate header : unnecessary - WARNING
Streams.Deallocate (Header);
end loop;
exception when others =>
D (D_Exception, "exception in Environment");
raise;
end Environnement;
begin
-- Set debugging information
Debugging.Set_Environment_Variable ("RPC");
Debugging.Set_Debugging_Name ("D", D_Debug);
Debugging.Set_Debugging_Name ("E", D_Exception);
Debugging.Set_Debugging_Name ("C", D_Communication);
Debugging.Set_Debugging_Name ("Z", D_Elaborate);
D (D_Elaborate, "To be elaborated");
-- When this body is elaborated we should ensure that RCI name server
-- has been already elaborated : this means that Establish_RPC_Receiver
-- has already been called and that Partition_RPC_Receiver is set
Environnement.Start;
D (D_Elaborate, "ELABORATED");
end System.RPC;