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544 | ------------------------------------------------------------------------------
-- --
-- GLADE COMPONENTS --
-- --
-- S Y S T E M . R P C --
-- --
-- B o d y --
-- --
-- Copyright (C) 1996-2020 Free Software Foundation, Inc. --
-- --
-- GARLIC 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. GARLIC is distributed in the hope that it will be useful, but --
-- WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABI- --
-- LITY 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 GARLIC; 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. --
-- --
------------------------------------------------------------------------------
with Ada.Exceptions; use Ada.Exceptions;
with System.Garlic; use System.Garlic;
with System.Garlic.Debug; use System.Garlic.Debug;
with System.Garlic.Exceptions; use System.Garlic.Exceptions;
with System.Garlic.Heart; use System.Garlic.Heart;
with System.Garlic.Priorities; use System.Garlic.Priorities;
with System.Garlic.Priorities.Mapping; use System.Garlic.Priorities.Mapping;
with System.Garlic.Soft_Links;
with System.Garlic.Units; use System.Garlic.Units;
with System.Garlic.Startup;
pragma Elaborate_All (System.Garlic.Startup);
pragma Warnings (Off, System.Garlic.Startup);
package body System.RPC is
use type System.Garlic.Types.Partition_ID;
-- This package needs extra comments ???
Private_Debug_Key : constant Debug_Key :=
Debug_Initialize ("S_RPC", "(s-rpc ): ");
procedure D
(Message : String;
Key : Debug_Key := Private_Debug_Key)
renames Print_Debug_Info;
RPC_Allowed : Boolean := False;
Establish_RPC_Watcher : System.Garlic.Soft_Links.Watcher_Access;
-- The current RPC receiver and its associated barrier
Allocate_Pool_Task : Allocate_Task_Procedure;
Abort_Pool_Task : Abort_Task_Procedure;
Initialize_Task_Pool : Parameterless_Procedure;
Shutdown_Task_Pool : Parameterless_Procedure;
type Session_Status is (Unknown, Running, Aborted, Completed);
type Session_Info is
record
PID : Types.Partition_ID;
Result : Streams.Stream_Element_Access;
Status : Session_Status;
-- Stamp : System.Garlic.Types.Stamp_Type;
end record;
subtype Valid_Session_Type is
Session_Type range No_Session + 1 .. Session_Type'Last;
Callers : array (Valid_Session_Type) of Session_Info;
Callers_Watcher : System.Garlic.Soft_Links.Watcher_Access;
type Dummy_Abort_Handler_Type is
new Garlic.Soft_Links.Abort_Handler_Type with null record;
procedure Raise_Partition_Error (PID : Types.Partition_ID);
procedure Handle_Request
(Partition : Types.Partition_ID;
Opcode : External_Opcode;
Query : access Streams.Params_Stream_Type;
Reply : access Streams.Params_Stream_Type;
Error : in out Error_Type);
-- Receive data
procedure Shutdown;
-- Shutdown System.RPC and its private child packages
procedure Wait_For
(Session : Session_Type;
Stream : out System.Garlic.Streams.Stream_Element_Access);
procedure Notify_Partition_Error
(Partition : Types.Partition_ID);
-- Call this procedure to unblock tasks waiting for RPC results from
-- a dead partition.
--------------
-- Allocate --
--------------
procedure Allocate
(Session : out Session_Type;
Partition : Partition_ID)
is
Version : Types.Version_Id;
begin
loop
System.Garlic.Soft_Links.Enter_Critical_Section;
for I in Callers'Range loop
if Callers (I).Status = Unknown then
Callers (I).Status := Running;
Callers (I).PID := Types.Partition_ID (Partition);
Session := I;
System.Garlic.Soft_Links.Leave_Critical_Section;
return;
end if;
end loop;
System.Garlic.Soft_Links.Lookup (Callers_Watcher, Version);
System.Garlic.Soft_Links.Leave_Critical_Section;
System.Garlic.Soft_Links.Differ (Callers_Watcher, Version);
end loop;
end Allocate;
----------------
-- Deallocate --
----------------
procedure Deallocate (Session : Session_Type)
is
begin
System.Garlic.Soft_Links.Enter_Critical_Section;
Callers (Session).Status := Unknown;
Callers (Session).PID := Types.Null_PID;
System.Garlic.Soft_Links.Update (Callers_Watcher);
System.Garlic.Soft_Links.Leave_Critical_Section;
end Deallocate;
------------
-- Do_APC --
------------
procedure Do_APC
(Partition : Partition_ID;
Params : access Params_Stream_Type)
is
use System.Garlic.Soft_Links;
Header : constant RPC_Header := (Kind => APC_Query);
Error : aliased Error_Type;
begin
Insert_RPC_Header (Params.X'Access, Header);
Types.Partition_ID'Write (Params, Types.Partition_ID (Partition));
Global_Priority'Write (Params, To_Global_Priority (Get_Priority));
Send (Types.Partition_ID (Partition),
Remote_Call,
Params.X'Access,
Error);
if Found (Error) then
Raise_Exception (Communication_Error'Identity,
Content (Error'Access));
end if;
D ("Execute APC on partition" & Partition'Img);
end Do_APC;
------------
-- Do_RPC --
------------
procedure Do_RPC
(Partition : Partition_ID;
Params : access Params_Stream_Type;
Result : access Params_Stream_Type)
is
use System.Garlic.Soft_Links;
Session : Session_Type;
Header : RPC_Header (RPC_Query);
Stream : Streams.Stream_Element_Access;
Handler : System.Garlic.Soft_Links.Abort_Handler_Type'Class
:= System.Garlic.Soft_Links.Abort_Handler;
Error : aliased Error_Type;
begin
-- pragma Debug (System.Garlic.Soft_Links.Set_Stamp (Types.No_Stamp));
-- pragma Debug (D (Stamp_Image ("rpc initiate")));
-- Initialize stamp. As a convention, when set_stamp parameter
-- is no stamp and when task stamp is no stamp, we initialize
-- task stamp to clock.
begin
pragma Abort_Defer;
Allocate (Session, Partition);
Header.Session := Session;
Insert_RPC_Header (Params.X'Access, Header);
Types.Partition_ID'Write (Params, Types.Partition_ID (Partition));
Global_Priority'Write (Params, To_Global_Priority (Get_Priority));
Send (Types.Partition_ID (Partition),
Remote_Call,
Params.X'Access,
Error);
if Found (Error) then
Raise_Exception (Communication_Error'Identity,
Content (Error'Access));
end if;
Handler.Session := Natural (Session);
Handler.Partition := Types.Partition_ID (Partition);
Handler.Waiting := True;
System.Garlic.Soft_Links.Adjust (Handler);
end;
D ("Execute session" & Session'Img & " on partition" & Partition'Img);
Wait_For (Session, Stream);
begin
pragma Abort_Defer;
Streams.Write (Result.X, Stream.all);
Streams.Free (Stream);
Handler.Waiting := False;
System.Garlic.Soft_Links.Adjust (Handler);
end;
-- pragma Debug (D (Stamp_Image ("rpc complete")));
-- pragma Debug (Soft_Links.Set_Stamp (Types.No_Stamp));
-- Reset task stamp to no stamp as the request has been
-- processed. By convention, task stamp differs from no stamp.
end Do_RPC;
----------------------------
-- Establish_RPC_Receiver --
----------------------------
procedure Establish_RPC_Receiver
(Partition : Partition_ID;
Receiver : RPC_Receiver)
is
pragma Unreferenced (Receiver);
begin
D ("Accept RPCs on this partition" & Partition'Img);
if Initialize_Task_Pool /= null then
Initialize_Task_Pool.all;
end if;
RPC_Allowed := True;
System.Garlic.Soft_Links.Update (Establish_RPC_Watcher);
Register_RPC_Error_Notifier (Notify_Partition_Error'Access);
end Establish_RPC_Receiver;
--------------
-- Finalize --
--------------
procedure Finalize
(Partition : Garlic.Types.Partition_ID;
Waiting : Boolean;
Session : Session_Type) is
begin
if Waiting then
System.Garlic.Soft_Links.Enter_Critical_Section;
if Callers (Session).Status = Running then
declare
Params : aliased Streams.Params_Stream_Type (0);
Header : constant RPC_Header := (Abortion_Query, Session);
Error : Error_Type;
begin
pragma Debug
(D ("Forward local abortion of session" & Session'Img &
" to partition" & Partition'Img));
Insert_RPC_Header (Params'Access, Header);
Callers (Session).Status := Aborted;
System.Garlic.Soft_Links.Update (Callers_Watcher);
System.Garlic.Soft_Links.Leave_Critical_Section;
Send (Partition, Remote_Call, Params'Access, Error);
Catch (Error);
end;
else
if Callers (Session).Status = Aborted then
Callers (Session).Status := Unknown;
end if;
System.Garlic.Soft_Links.Update (Callers_Watcher);
System.Garlic.Soft_Links.Leave_Critical_Section;
end if;
end if;
end Finalize;
--------------------
-- Handle_Request --
--------------------
procedure Handle_Request
(Partition : Types.Partition_ID;
Opcode : External_Opcode;
Query : access Streams.Params_Stream_Type;
Reply : access Streams.Params_Stream_Type;
Error : in out Error_Type)
is
pragma Unreferenced (Opcode);
pragma Unreferenced (Reply);
pragma Unreferenced (Error);
Header : constant RPC_Header := RPC_Header'Input (Query);
begin
case Header.Kind is
when RPC_Query | APC_Query =>
declare
Params_Copy : constant Streams.Params_Stream_Access :=
new Streams.Params_Stream_Type (Query.Initial_Size);
Session : Session_Type := Session_Type'First;
Asynchronous : constant Boolean := Header.Kind = APC_Query;
begin
Streams.Move (Query.all, Params_Copy.all);
if not Asynchronous then
Session := Header.Session;
D ("Execute session" & Session'Img &
" from partition" & Partition'Img);
else
D ("Execute APC from partition" & Partition'Img);
end if;
Allocate_Pool_Task
(Partition,
Session,
-- Soft_Links.Get_Stamp,
Params_Copy,
Asynchronous);
end;
when RPC_Reply =>
System.Garlic.Soft_Links.Enter_Critical_Section;
if Callers (Header.Session).Status = Aborted then
Callers (Header.Session).Status := Unknown;
else
Callers (Header.Session).Status := Completed;
Callers (Header.Session).Result :=
Streams.To_Stream_Element_Access (Query);
-- Callers (Header.Session).Stamp :=
-- System.Garlic.Soft_Links.Get_Stamp;
end if;
System.Garlic.Soft_Links.Update (Callers_Watcher);
System.Garlic.Soft_Links.Leave_Critical_Section;
when Abortion_Query =>
Abort_Pool_Task (Partition, Header.Session);
when Abortion_Reply =>
System.Garlic.Soft_Links.Enter_Critical_Section;
Callers (Header.Session).Status := Unknown;
Callers (Header.Session).PID := Types.Null_PID;
System.Garlic.Soft_Links.Update (Callers_Watcher);
System.Garlic.Soft_Links.Leave_Critical_Section;
end case;
end Handle_Request;
-----------------------
-- Insert_RPC_Header --
-----------------------
procedure Insert_RPC_Header
(Params : access Streams.Params_Stream_Type;
Header : RPC_Header)
is
begin
Streams.Insert (Params.all);
RPC_Header'Output (Params, Header);
end Insert_RPC_Header;
----------------------------
-- Notify_Partition_Error --
----------------------------
procedure Notify_Partition_Error
(Partition : Types.Partition_ID)
is
begin
if not Shutdown_Activated then
Invalidate_Partition_Units (Partition);
Raise_Partition_Error (Partition);
end if;
end Notify_Partition_Error;
---------------------------
-- Raise_Partition_Error --
---------------------------
procedure Raise_Partition_Error (PID : Types.Partition_ID)
is
Modified : Boolean := False;
begin
System.Garlic.Soft_Links.Enter_Critical_Section;
for I in Callers'Range loop
if Callers (I).PID = PID
and then Callers (I).Status = Running
then
Callers (I).Status := Aborted;
Modified := True;
end if;
end loop;
if Modified then
System.Garlic.Soft_Links.Update (Callers_Watcher);
end if;
System.Garlic.Soft_Links.Leave_Critical_Section;
end Raise_Partition_Error;
----------
-- Read --
----------
procedure Read
(Stream : in out Params_Stream_Type;
Item : out Ada.Streams.Stream_Element_Array;
Last : out Ada.Streams.Stream_Element_Offset)
is
begin
System.Garlic.Streams.Read (Stream.X, Item, Last);
exception
when E : System.Garlic.Communication_Error =>
Raise_Exception (Communication_Error'Identity,
Exception_Message (E));
end Read;
------------------------
-- Register_Task_Pool --
------------------------
procedure Register_Task_Pool
(Allocate_Task : Allocate_Task_Procedure;
Abort_Task : Abort_Task_Procedure;
Initialize : Parameterless_Procedure;
Shutdown : Parameterless_Procedure) is
begin
Allocate_Pool_Task := Allocate_Task;
Abort_Pool_Task := Abort_Task;
Initialize_Task_Pool := Initialize;
Shutdown_Task_Pool := Shutdown;
end Register_Task_Pool;
--------------
-- Shutdown --
--------------
procedure Shutdown is
begin
pragma Debug (D ("Enter RPC shutdown"));
if Shutdown_Task_Pool /= null then
Shutdown_Task_Pool.all;
end if;
Units.Shutdown;
pragma Debug (D ("Leave RPC shutdown"));
end Shutdown;
--------------
-- Wait_For --
--------------
procedure Wait_For
(Session : Session_Type;
Stream : out Streams.Stream_Element_Access)
is
Version : Types.Version_Id;
begin
loop
D ("check for session" & Session'Img);
System.Garlic.Soft_Links.Enter_Critical_Section;
case Callers (Session).Status is
when Completed =>
Stream := Callers (Session).Result;
Callers (Session).Status := Unknown;
Callers (Session).PID := Types.Null_PID;
Callers (Session).Result := null;
System.Garlic.Soft_Links.Update (Callers_Watcher);
System.Garlic.Soft_Links.Leave_Critical_Section;
return;
when Aborted =>
Callers (Session).Status := Unknown;
Callers (Session).PID := Types.Null_PID;
Callers (Session).Result := null;
System.Garlic.Soft_Links.Update (Callers_Watcher);
System.Garlic.Soft_Links.Leave_Critical_Section;
Raise_Exception (Communication_Error'Identity,
"remote procedure call aborted");
when others =>
System.Garlic.Soft_Links.Lookup (Callers_Watcher, Version);
System.Garlic.Soft_Links.Leave_Critical_Section;
end case;
System.Garlic.Soft_Links.Differ (Callers_Watcher, Version);
end loop;
end Wait_For;
----------------------
-- When_Established --
----------------------
procedure When_Established
is
begin
if not RPC_Allowed then
System.Garlic.Soft_Links.Differ
(Establish_RPC_Watcher, System.Garlic.Types.No_Version);
end if;
end When_Established;
-----------
-- Write --
-----------
procedure Write
(Stream : in out Params_Stream_Type;
Item : Ada.Streams.Stream_Element_Array)
is
begin
Streams.Write (Stream.X, Item);
exception
when E : System.Garlic.Communication_Error =>
Raise_Exception (Communication_Error'Identity,
Exception_Message (E));
end Write;
begin
System.Garlic.Soft_Links.Create
(Establish_RPC_Watcher, System.Garlic.Types.No_Version);
System.Garlic.Soft_Links.Create (Callers_Watcher);
Register_Handler (Remote_Call, Handle_Request'Access);
System.Garlic.Soft_Links.Register_RPC_Shutdown (Shutdown'Access);
System.Garlic.Soft_Links.Register_Abort_Handler
(new Dummy_Abort_Handler_Type);
end System.RPC;
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