fpc/rtl/objpas/classes/classes.inc

{
    This file is part of the Free Component Library (FCL)
    Copyright (c) 1999-2000 by Michael Van Canneyt and Florian Klaempfl

    See the file COPYING.FPC, included in this distribution,
    for details about the copyright.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

 **********************************************************************}

{**********************************************************************
 *       Class implementations are in separate files.                 *
 **********************************************************************}

type
{$ifdef CPU16}
  TFilerFlagsInt = Byte;
{$else CPU16}
  TFilerFlagsInt = LongInt;
{$endif CPU16}

var
  ClassList : TThreadlist;
  ClassAliasList : TStringList;

{
 Include all message strings

 Add a language with IFDEF LANG_NAME
 just befor the final ELSE. This way English will always be the default.
}

{$IFDEF LANG_GERMAN}
{$i constsg.inc}
{$ELSE}
{$IFDEF LANG_SPANISH}
{$i constss.inc}
{$ENDIF}
{$ENDIF}

{ Utility routines }
{$i util.inc}

{ TBits implementation }
{$i bits.inc}

{ All streams implementations: }
{ Tstreams THandleStream TFileStream TResourcseStreams TStringStream }
{ TCustomMemoryStream TMemoryStream }
{$i streams.inc}

{ TParser implementation}
{$i parser.inc}

{ TCollection and TCollectionItem implementations }
{$i collect.inc}

{ TList and TThreadList implementations }
{$i lists.inc}

{ TStrings and TStringList implementations }
{$i stringl.inc}

{ TThread implementation }

{ system independend threading code }

var
  { event executed by SychronizeInternal to wake main thread if it sleeps in
    CheckSynchronize }
  SynchronizeTimeoutEvent: PRtlEvent;
  { the head of the queue containing the entries to be Synchronized - Nil if the
    queue is empty }
  ThreadQueueHead: TThread.PThreadQueueEntry;
  { the tail of the queue containing the entries to be Synchronized - Nil if the
    queue is empty }
  ThreadQueueTail: TThread.PThreadQueueEntry;
  { used for serialized access to the queue }
  ThreadQueueLock: TRtlCriticalSection;
  { usage counter for ThreadQueueLock }
  ThreadQueueLockCounter : longint;
  { this list holds all instances of external threads that need to be freed at
    the end of the program }
  ExternalThreads: TThreadList;
  { this list signals that the ExternalThreads list is cleared and thus the
    thread instances don't need to remove themselves }
  ExternalThreadsCleanup: Boolean = False;

  { this must be a global var, otherwise unwanted optimizations might happen in
    TThread.SpinWait() }
  SpinWaitDummy: LongWord;


{$ifdef FPC_HAS_FEATURE_THREADING}
threadvar
{$else}
var
{$endif}
  { the instance of the current thread; in case of an external thread this is
    Nil until TThread.GetCurrentThread was called once (the RTLs need to ensure
    that threadvars are initialized with 0!) }
  CurrentThreadVar: TThread;


type
  { this type is used if a thread is created using
    TThread.CreateAnonymousThread }
  TAnonymousThread = class(TThread)
  private
    fProc: TProcedure;
  protected
    procedure Execute; override;
  public
    { as in TThread aProc needs to be changed to TProc once closures are
      supported }
    constructor Create(aProc: TProcedure);
  end;


procedure TAnonymousThread.Execute;
begin
  fProc();
end;


constructor TAnonymousThread.Create(aProc: TProcedure);
begin
  { an anonymous thread is created suspended and with FreeOnTerminate set }
  inherited Create(True);
  FreeOnTerminate := True;
  fProc := aProc;
end;


type
  { this type is used by TThread.GetCurrentThread if the thread does not yet
    have a value in CurrentThreadVar (Note: the main thread is also created as
    a TExternalThread) }
  TExternalThread = class(TThread)
  protected
    { dummy method to remove the warning }
    procedure Execute; override;
  public
    constructor Create;
    destructor Destroy; override;
  end;


procedure TExternalThread.Execute;
begin
  { empty }
end;


constructor TExternalThread.Create;
begin
  FExternalThread := True;
  { the parameter is unimportant if FExternalThread is True }
  inherited Create(False);
  with ExternalThreads.LockList do
    try
      Add(Self);
    finally
      ExternalThreads.UnlockList;
    end;
end;


destructor TExternalThread.Destroy;
begin
  inherited;
  if not ExternalThreadsCleanup then
    with ExternalThreads.LockList do
      try
        Extract(Self);
      finally
        ExternalThreads.UnlockList;
      end;
end;


function ThreadProc(ThreadObjPtr: Pointer): PtrInt;
  var
    FreeThread: Boolean;
    Thread: TThread absolute ThreadObjPtr;
  begin
    { if Suspend checks FSuspended before doing anything, make sure it }
    { knows we're currently not suspended (this flag may have been set }
    { to true if CreateSuspended was true)                             }
//    Thread.FSuspended:=false;
    // wait until AfterConstruction has been called, so we cannot
    // free ourselves before TThread.Create has finished
    // (since that one may check our VTM in case of $R+, and
    //  will call the AfterConstruction method in all cases)
//    Thread.Suspend;
    try
      { The thread may be already terminated at this point, e.g. if it was intially
        suspended, or if it wasn't ever scheduled for execution for whatever reason.
        So bypass user code if terminated. }
      if not Thread.Terminated then begin
        CurrentThreadVar := Thread;
        Thread.Execute;
      end;
    except
      Thread.FFatalException := TObject(AcquireExceptionObject);
    end;
    FreeThread := Thread.FFreeOnTerminate;
    Result := Thread.FReturnValue;
    Thread.FFinished := True;
    Thread.DoTerminate;
    if FreeThread then
      Thread.Free;
{$ifdef FPC_HAS_FEATURE_THREADING}
    EndThread(Result);
{$endif}
  end;

{ system-dependent code }
{$i tthread.inc}


constructor TThread.Create(CreateSuspended: Boolean;
                           const StackSize: SizeUInt);
begin
  inherited Create;
{$ifdef FPC_HAS_FEATURE_THREADING}
    InterlockedIncrement(ThreadQueueLockCounter);
{$endif}
  if FExternalThread then
{$ifdef FPC_HAS_FEATURE_THREADING}
    FThreadID := GetCurrentThreadID
{$else}
    FThreadID := 0{GetCurrentThreadID}
{$endif}
  else
    SysCreate(CreateSuspended, StackSize);
end;


destructor TThread.Destroy;
begin
  if not FExternalThread then begin
    SysDestroy;
{$ifdef FPC_HAS_FEATURE_THREADING}
    if FHandle <> TThreadID(0) then
      CloseThread(FHandle);
{$endif}
  end;
  RemoveQueuedEvents(Self);
  DoneSynchronizeEvent;
{$ifdef FPC_HAS_FEATURE_THREADING}
  if InterlockedDecrement(ThreadQueueLockCounter)=0 then
    DoneCriticalSection(ThreadQueueLock);
{$endif}
  { set CurrentThreadVar to Nil? }
  inherited Destroy;
end;


procedure TThread.Start;
begin
  { suspend/resume are now deprecated in Delphi (they also don't work
    on most platforms in FPC), so a different method was required
    to start a thread if it's create with fSuspended=true -> that's
    what this method is for. }
  Resume;
end;

function TThread.GetSuspended: Boolean;
begin
  GetSuspended:=FSuspended;
end;


procedure TThread.AfterConstruction;
begin
  inherited AfterConstruction;
// enable for all platforms once http://bugs.freepascal.org/view.php?id=16884
// is fixed for all platforms (in case the fix for non-unix platforms also
// requires this field at least)
{$if defined(unix) or defined(windows) or defined(os2) or defined(hasamiga)}
  if not FExternalThread and not FInitialSuspended then
    Resume;
{$endif}
end;


procedure ExecuteThreadQueueEntry(aEntry: TThread.PThreadQueueEntry);
begin
  if Assigned(aEntry^.Method) then
    aEntry^.Method()
  // enable once closures are supported
  {else
    aEntry^.ThreadProc();}
end;


procedure ThreadQueueAppend(aEntry: TThread.PThreadQueueEntry; aQueueIfMain: Boolean);
var
  thd: TThread;
  issync: Boolean;
begin
  { do we really need a synchronized call? }
{$ifdef FPC_HAS_FEATURE_THREADING}
  if (GetCurrentThreadID = MainThreadID) and (not aQueueIfMain or not IsMultiThread) then
{$endif}
  begin
    try
      ExecuteThreadQueueEntry(aEntry);
    finally
      if not Assigned(aEntry^.SyncEvent) then
        Dispose(aEntry);
    end;
{$ifdef FPC_HAS_FEATURE_THREADING}
  end else begin
    { store thread and whether we're dealing with a synchronized event; the
      event record itself might already be freed after the ThreadQueueLock is
      released (in case of a Queue() call; for a Synchronize() call the record
      will stay valid, thus accessing SyncEvent later on (if issync is true) is
      okay) }
    thd := aEntry^.Thread;
    issync := Assigned(aEntry^.SyncEvent);

    System.EnterCriticalSection(ThreadQueueLock);
    try
      { add the entry to the thread queue }
      if Assigned(ThreadQueueTail) then begin
        ThreadQueueTail^.Next := aEntry;
      end else
        ThreadQueueHead := aEntry;
      ThreadQueueTail := aEntry;
    finally
      System.LeaveCriticalSection(ThreadQueueLock);
    end;

    { ensure that the main thread knows that something awaits }
    RtlEventSetEvent(SynchronizeTimeoutEvent);
    if assigned(WakeMainThread) then
      WakeMainThread(thd);

    { is this a Synchronize or Queue entry? }
    if issync then begin
      RtlEventWaitFor(aEntry^.SyncEvent);
      if Assigned(aEntry^.Exception) then
        raise aEntry^.Exception;
    end;
{$endif def FPC_HAS_FEATURE_THREADING}
  end;
end;


procedure TThread.InitSynchronizeEvent;
  begin
    if Assigned(FSynchronizeEntry) then
      Exit;

    New(FSynchronizeEntry);
    FillChar(FSynchronizeEntry^, SizeOf(TThreadQueueEntry), 0);
    FSynchronizeEntry^.Thread := Self;
    FSynchronizeEntry^.ThreadID := ThreadID;
{$ifdef FPC_HAS_FEATURE_THREADING}
    FSynchronizeEntry^.SyncEvent := RtlEventCreate;
{$else}
    FSynchronizeEntry^.SyncEvent := nil{RtlEventCreate};
{$endif}
  end;


procedure TThread.DoneSynchronizeEvent;
  begin
    if not Assigned(FSynchronizeEntry) then
      Exit;

{$ifdef FPC_HAS_FEATURE_THREADING}
    RtlEventDestroy(FSynchronizeEntry^.SyncEvent);
{$endif}
    Dispose(FSynchronizeEntry);
    FSynchronizeEntry := Nil;
  end;


class procedure TThread.Synchronize(AThread: TThread; AMethod: TThreadMethod);
  var
    syncentry: PThreadQueueEntry;
    thread: TThread;
  begin
{$ifdef FPC_HAS_FEATURE_THREADING}
    if Assigned(AThread) and (AThread.ThreadID = GetCurrentThreadID) then
{$else}
    if Assigned(AThread) then
{$endif}
      thread := AThread
    else if Assigned(CurrentThreadVar) then
      thread := CurrentThreadVar
    else begin
      thread := Nil;
      { use a local synchronize event }
      New(syncentry);
      FillChar(syncentry^, SizeOf(TThreadQueueEntry), 0);
{$ifdef FPC_HAS_FEATURE_THREADING}
      syncentry^.ThreadID := GetCurrentThreadID;
      syncentry^.SyncEvent := RtlEventCreate;
{$else}
      syncentry^.ThreadID := 0{GetCurrentThreadID};
      syncentry^.SyncEvent := nil{RtlEventCreate};
{$endif}
    end;

    if Assigned(thread) then begin
      { the Synchronize event is instantiated on demand }
      thread.InitSynchronizeEvent;

      syncentry := thread.FSynchronizeEntry;
    end;

    syncentry^.Exception := Nil;
    syncentry^.Method := AMethod;
    try
      ThreadQueueAppend(syncentry, False);
    finally
      syncentry^.Method := Nil;
      syncentry^.Next := Nil;

      if not Assigned(thread) then begin
        { clean up again }
{$ifdef FPC_HAS_FEATURE_THREADING}
        RtlEventDestroy(syncentry^.SyncEvent);
{$endif}
        Dispose(syncentry);
      end;
    end;
  end;


procedure TThread.Synchronize(AMethod: TThreadMethod);
  begin
    TThread.Synchronize(self,AMethod);
  end;

Function PopThreadQueueHead : TThread.PThreadQueueEntry;

begin
  Result:=ThreadQueueHead;
  if (Result<>Nil) then
    begin
{$ifdef FPC_HAS_FEATURE_THREADING}
    System.EnterCriticalSection(ThreadQueueLock);
    try
{$endif}
      Result:=ThreadQueueHead;
      if Result<>Nil then
        ThreadQueueHead:=ThreadQueueHead^.Next;
      if Not Assigned(ThreadQueueHead) then
        ThreadQueueTail := Nil;
{$ifdef FPC_HAS_FEATURE_THREADING}
    finally
      System.LeaveCriticalSection(ThreadQueueLock);
    end;
{$endif}
    end;
end;

function CheckSynchronize(timeout : longint=0) : boolean;

{ assumes being called from GUI thread }
var
  ExceptObj: TObject;
  tmpentry: TThread.PThreadQueueEntry;

begin
  result:=false;
  { first sanity check }
  if Not IsMultiThread then
    Exit
{$ifdef FPC_HAS_FEATURE_THREADING}
  { second sanity check }
  else if GetCurrentThreadID<>MainThreadID then
    raise EThread.CreateFmt(SCheckSynchronizeError,[GetCurrentThreadID]);
  if timeout>0 then
    RtlEventWaitFor(SynchronizeTimeoutEvent,timeout)
  else
    RtlEventResetEvent(SynchronizeTimeoutEvent);
  tmpentry := PopThreadQueueHead;
  while Assigned(tmpentry) do
    begin
    { step 2: execute the method }
    exceptobj := Nil;
    try
      ExecuteThreadQueueEntry(tmpentry);
    except
      exceptobj := TObject(AcquireExceptionObject);
    end;
    { step 3: error handling and cleanup }
    if Assigned(tmpentry^.SyncEvent) then
      begin
      { for Synchronize entries we pass back the Exception and trigger
        the event that Synchronize waits in }
      tmpentry^.Exception := exceptobj;
      RtlEventSetEvent(tmpentry^.SyncEvent)
      end
    else
      begin
      { for Queue entries we dispose the entry and raise the exception }
      Dispose(tmpentry);
      if Assigned(exceptobj) then
        raise exceptobj;
      end;
    tmpentry := PopThreadQueueHead;
    end
{$endif};
end;


class function TThread.GetCurrentThread: TThread;
begin
  { if this is the first time GetCurrentThread is called for an external thread
    we need to create a corresponding TExternalThread instance }
  Result := CurrentThreadVar;
  if not Assigned(Result) then begin
    Result := TExternalThread.Create;
    CurrentThreadVar := Result;
  end;
end;


class function TThread.GetIsSingleProcessor: Boolean;
begin
  Result := FProcessorCount <= 1;
end;


procedure TThread.Queue(aMethod: TThreadMethod);
begin
  Queue(Self, aMethod);
end;


class procedure TThread.Queue(aThread: TThread; aMethod: TThreadMethod); static;
begin
  InternalQueue(aThread, aMethod, False);
end;


class procedure TThread.InternalQueue(aThread: TThread; aMethod: TThreadMethod; aQueueIfMain: Boolean); static;
var
  queueentry: PThreadQueueEntry;
begin
  New(queueentry);
  FillChar(queueentry^, SizeOf(TThreadQueueEntry), 0);
  queueentry^.Thread := aThread;
{$ifdef FPC_HAS_FEATURE_THREADING}
  queueentry^.ThreadID := GetCurrentThreadID;
{$else}
  queueentry^.ThreadID := 0{GetCurrentThreadID};
{$endif}
  queueentry^.Method := aMethod;

  { the queueentry is freed by CheckSynchronize (or by RemoveQueuedEvents) }
  ThreadQueueAppend(queueentry, aQueueIfMain);
end;


procedure TThread.ForceQueue(aMethod: TThreadMethod);
begin
  ForceQueue(Self, aMethod);
end;


class procedure TThread.ForceQueue(aThread: TThread; aMethod: TThreadMethod); static;
begin
  InternalQueue(aThread, aMethod, True);
end;

class procedure TThread.RemoveQueuedEvents(aThread: TThread; aMethod: TThreadMethod);
var
  entry, tmpentry, lastentry: PThreadQueueEntry;
begin
  { anything to do at all? }
  if not Assigned(aThread) and not Assigned(aMethod) then
    Exit;

{$ifdef FPC_HAS_FEATURE_THREADING}
  System.EnterCriticalSection(ThreadQueueLock);
  try
{$endif}
    lastentry := Nil;
    entry := ThreadQueueHead;
    while Assigned(entry) do begin
      { first check for the thread }
      if Assigned(aThread) and (entry^.Thread <> aThread) and (entry^.ThreadID <> aThread.ThreadID) then begin
        lastentry := entry;
        entry := entry^.Next;
        Continue;
      end;
      { then check for the method }
      if Assigned(aMethod) and (entry^.Method <> aMethod) then begin
        lastentry := entry;
        entry := entry^.Next;
        Continue;
      end;
      { skip entries added by Synchronize }
      if Assigned(entry^.SyncEvent) then begin
        lastentry := entry;
        entry := entry^.Next;
        Continue;
      end;

      { ok, we need to remove this entry }

      tmpentry := entry;
      if Assigned(lastentry) then
        lastentry^.Next := entry^.Next;
      entry := entry^.Next;
      if ThreadQueueHead = tmpentry then
        ThreadQueueHead := entry;
      if ThreadQueueTail = tmpentry then
        ThreadQueueTail := lastentry;
      { only dispose events added by Queue }
      if not Assigned(tmpentry^.SyncEvent) then
        Dispose(tmpentry);
    end;
{$ifdef FPC_HAS_FEATURE_THREADING}
  finally
    System.LeaveCriticalSection(ThreadQueueLock);
  end;
{$endif}
end;


class procedure TThread.RemoveQueuedEvents(aMethod: TThreadMethod);
begin
  RemoveQueuedEvents(Nil, aMethod);
end;


class procedure TThread.RemoveQueuedEvents(aThread: TThread);
begin
  RemoveQueuedEvents(aThread, Nil);
end;


class function TThread.CheckTerminated: Boolean;
begin
  { this method only works with threads created by TThread, so we can make a
    shortcut here }
  if not Assigned(CurrentThreadVar) then
    raise EThreadExternalException.Create(SThreadExternal);
  Result := CurrentThreadVar.FTerminated;
end;


class procedure TThread.SetReturnValue(aValue: Integer);
begin
  { this method only works with threads created by TThread, so we can make a
    shortcut here }
  if not Assigned(CurrentThreadVar) then
    raise EThreadExternalException.Create(SThreadExternal);
  CurrentThreadVar.FReturnValue := aValue;
end;


class function TThread.CreateAnonymousThread(aProc: TProcedure): TThread;
begin
  if not Assigned(aProc) then
    raise Exception.Create(SNoProcGiven);
  Result := TAnonymousThread.Create(aProc);
end;


{$ifdef THREADNAME_IS_ANSISTRING}
{ the platform implements the AnsiString variant and the UnicodeString variant
  simply calls the AnsiString variant }
class procedure TThread.NameThreadForDebugging(aThreadName: UnicodeString; aThreadID: TThreadID);
begin
  NameThreadForDebugging(AnsiString(aThreadName), aThreadID);
end;

  {$ifndef HAS_TTHREAD_NAMETHREADFORDEBUGGING}
class procedure TThread.NameThreadForDebugging(aThreadName: AnsiString; aThreadID: TThreadID);
begin
  { empty }
end;
  {$endif}
{$else}
  {$ifndef HAS_TTHREAD_NAMETHREADFORDEBUGGING}
{ the platform implements the UnicodeString variant and the AnsiString variant
  simply calls the UnicodeString variant }
class procedure TThread.NameThreadForDebugging(aThreadName: UnicodeString; aThreadID: TThreadID);
begin
  { empty }
end;
  {$endif}


class procedure TThread.NameThreadForDebugging(aThreadName: AnsiString; aThreadID: TThreadID);
begin
  NameThreadForDebugging(UnicodeString(aThreadName), aThreadID);
end;
{$endif}


class procedure TThread.Yield;
begin
{$ifdef FPC_HAS_FEATURE_THREADING}
  ThreadSwitch;
{$endif}
end;


class procedure TThread.Sleep(aMilliseconds: Cardinal);
begin
  SysUtils.Sleep(aMilliseconds);
end;


class procedure TThread.SpinWait(aIterations: LongWord);
var
  i: LongWord;
begin
  { yes, it's just a simple busy wait to burn some cpu cycles... and as the job
    of this loop is to burn CPU cycles we switch off any optimizations that
    could interfere with this (e.g. loop unrolling) }
  { Do *NOT* do $PUSH, $OPTIMIZATIONS OFF, <code>, $POP because optimization is
    not a local switch, which means $PUSH/POP doesn't affect it, so that turns
    off *ALL* optimizations for code below this point. Thanks to this we shipped
    large parts of the classes unit with optimizations off between 2012-12-27
    and 2014-06-06.
    Instead, use a global var for the spinlock, because that is always handled
    as volatile, so the access won't be optimized away by the compiler. (KB) }
  for i:=1 to aIterations do
    begin
      Inc(SpinWaitDummy); // SpinWaitDummy *MUST* be global
    end;
end;


{$ifndef HAS_TTHREAD_GETSYSTEMTIMES}
class procedure TThread.GetSystemTimes(out aSystemTimes: TSystemTimes);
begin
  { by default we just return a zeroed out record }
  FillChar(aSystemTimes, SizeOf(aSystemTimes), 0);
end;
{$endif}


class function TThread.GetTickCount: LongWord;
begin
  Result := SysUtils.GetTickCount;
end;


class function TThread.GetTickCount64: QWord;
begin
  Result := SysUtils.GetTickCount64;
end;

{ TSimpleThread allows objects to create a threading method without defining
  a new thread class }

Type
  TSimpleThread = class(TThread)
  private
    FExecuteMethod: TThreadExecuteHandler;
  protected
    procedure Execute; override;
  public
    constructor Create(ExecuteMethod: TThreadExecuteHandler; AOnterminate : TNotifyEvent);
  end;

  TSimpleStatusThread = class(TThread)
  private
    FExecuteMethod: TThreadExecuteStatusHandler;
    FStatus : String;
    FOnStatus : TThreadStatusNotifyEvent;
  protected
    procedure Execute; override;
    Procedure DoStatus;
    Procedure SetStatus(Const AStatus : String);
  public
    constructor Create(ExecuteMethod: TThreadExecuteStatusHandler; AOnStatus : TThreadStatusNotifyEvent; AOnterminate : TNotifyEvent);
  end;

  TSimpleProcThread = class(TThread)
  private
    FExecuteMethod: TThreadExecuteCallBack;
    FCallOnTerminate : TNotifyCallBack;
    FData : Pointer;
  protected
    Procedure TerminateCallBack(Sender : TObject);
    procedure Execute; override;
  public
    constructor Create(ExecuteMethod: TThreadExecuteCallBack; AData : Pointer; AOnterminate : TNotifyCallBack);
  end;

  TSimpleStatusProcThread = class(TThread)
  private
    FExecuteMethod: TThreadExecuteStatusCallBack;
    FCallOnTerminate : TNotifyCallBack;
    FStatus : String;
    FOnStatus : TThreadStatusNotifyCallBack;
    FData : Pointer;
  protected
    procedure Execute; override;
    Procedure DoStatus;
    Procedure SetStatus(Const AStatus : String);
    Procedure TerminateCallBack(Sender : TObject);
  public
    constructor Create(ExecuteMethod: TThreadExecuteStatusCallBack; AData : Pointer; AOnStatus : TThreadStatusNotifyCallBack; AOnterminate : TNotifyCallBack);
  end;


{ TSimpleThread }

constructor TSimpleThread.Create(ExecuteMethod: TThreadExecuteHandler; AOnTerminate: TNotifyEvent);
begin
  FExecuteMethod := ExecuteMethod;
  OnTerminate := AOnTerminate;
  inherited Create(False);
end;

procedure TSimpleThread.Execute;
begin
  FreeOnTerminate := True;
  FExecuteMethod;
end;

{ TSimpleStatusThread }

constructor TSimpleStatusThread.Create(ExecuteMethod: TThreadExecuteStatusHandler;AOnStatus : TThreadStatusNotifyEvent; AOnTerminate: TNotifyEvent);
begin
  FExecuteMethod := ExecuteMethod;
  OnTerminate := AOnTerminate;
  FOnStatus:=AOnStatus;
  FStatus:='';
  inherited Create(False);
end;

procedure TSimpleStatusThread.Execute;
begin
  FreeOnTerminate := True;
  FExecuteMethod(@SetStatus);
end;

procedure TSimpleStatusThread.SetStatus(Const AStatus : String);
begin
  If (AStatus=FStatus) then
    exit;
  FStatus:=AStatus;
  If Assigned(FOnStatus) then
    Synchronize(@DoStatus);
end;

procedure TSimpleStatusThread.DoStatus;
begin
   FOnStatus(Self,FStatus);
end;


{ TSimpleProcThread }

constructor TSimpleProcThread.Create(ExecuteMethod: TThreadExecuteCallBack; AData : Pointer; AOnTerminate: TNotifyCallBack);
begin
  FExecuteMethod := ExecuteMethod;
  FCallOnTerminate := AOnTerminate;
  FData:=AData;
  If Assigned(FCallOnTerminate) then
    OnTerminate:=@TerminateCallBack;
  inherited Create(False);
end;

procedure TSimpleProcThread.Execute;
begin
  FreeOnTerminate := True;
  FExecuteMethod(FData);
end;

procedure TSimpleProcThread.TerminateCallBack(Sender : TObject);

begin
  if Assigned(FCallOnTerminate) then
    FCallOnTerminate(Sender,FData);
end;

{ TSimpleStatusProcThread }

constructor TSimpleStatusProcThread.Create(ExecuteMethod: TThreadExecuteStatusCallback; AData : Pointer; AOnStatus : TThreadStatusNotifyCallBack; AOnTerminate: TNotifyCallBack);
begin
  FExecuteMethod := ExecuteMethod;
  FCallOnTerminate := AOnTerminate;
  FData:=AData;
  If Assigned(FCallOnTerminate) then
    OnTerminate:=@TerminateCallBack;
  FOnStatus:=AOnStatus;
  FStatus:='';
  inherited Create(False);
end;

procedure TSimpleStatusProcThread.Execute;
begin
  FreeOnTerminate := True;
  FExecuteMethod(FData,@SetStatus);
end;

procedure TSimpleStatusProcThread.SetStatus(Const AStatus : String);
begin
  If (AStatus=FStatus) then
    exit;
  FStatus:=AStatus;
  If Assigned(FOnStatus) then
    Synchronize(@DoStatus);
end;

procedure TSimpleStatusProcThread.DoStatus;
begin
   FOnStatus(Self,FData,FStatus);
end;

procedure TSimpleStatusProcThread.TerminateCallBack(Sender : TObject);

begin
  if Assigned(FCallOnTerminate) then
    FCallOnTerminate(Sender,FData);
end;


Class Function TThread.ExecuteInThread(AMethod : TThreadExecuteHandler; AOnTerminate : TNotifyEvent = Nil) : TThread;

begin
  Result:=TSimpleThread.Create(AMethod,AOnTerminate);
end;

Class Function TThread.ExecuteInThread(AMethod : TThreadExecuteCallback; AData : Pointer; AOnTerminate : TNotifyCallback = Nil) : TThread;

begin
  Result:=TSimpleProcThread.Create(AMethod,AData,AOnTerminate);
end;

Class Function TThread.ExecuteInThread(AMethod : TThreadExecuteStatusHandler; AOnStatus : TThreadStatusNotifyEvent; AOnTerminate : TNotifyEvent = Nil) : TThread;

begin
  If Not Assigned(AOnStatus) then
    Raise EThread.Create(SErrStatusCallBackRequired);
  Result:=TSimpleStatusThread.Create(AMethod,AOnStatus,AOnTerminate);
end;

Class Function TThread.ExecuteInThread(AMethod : TThreadExecuteStatusCallback; AOnStatus : TThreadStatusNotifyCallback;AData : Pointer = Nil;  AOnTerminate : TNotifyCallBack = Nil) : TThread;

begin
  If Not Assigned(AOnStatus) then
    Raise EThread.Create(SErrStatusCallBackRequired);
  Result:=TSimpleStatusProcThread.Create(AMethod,AData,AOnStatus,AOnTerminate);
end;

{ TPersistent implementation }
{$i persist.inc }

{$i sllist.inc}
{$i resref.inc}

{ TComponent implementation }
{$i compon.inc}

{ TBasicAction implementation }
{$i action.inc}

{ TDataModule implementation }
{$i dm.inc}

{ Class and component registration routines }
{$I cregist.inc}



{ Interface related stuff }
{$I intf.inc}

{**********************************************************************
 *       Miscellaneous procedures and functions                       *
 **********************************************************************}

function ExtractStrings(Separators, WhiteSpace: TSysCharSet; Content: PChar; Strings: TStrings; AddEmptyStrings : Boolean = False): Integer;
var
  b, c : pchar;

  procedure SkipWhitespace;
    begin
      while (c^ in Whitespace) do
        inc (c);
    end;

  procedure AddString;
    var
      l : integer;
      s : string;
    begin
      l := c-b;
      if (l > 0) or AddEmptyStrings then
        begin
          if assigned(Strings) then
            begin
              setlength(s, l);
              if l>0 then
                move (b^, s[1],l*SizeOf(char));
              Strings.Add (s);
            end;
          inc (result);
        end;
    end;

var
  quoted : char;
begin
  result := 0;
  c := Content;
  Quoted := #0;
  Separators := Separators + [#13, #10] - ['''','"'];
  SkipWhitespace;
  b := c;
  while (c^ <> #0) do
    begin
      if (c^ = Quoted) then
        begin
          if ((c+1)^ = Quoted) then
            inc (c)
          else
            Quoted := #0
        end
      else if (Quoted = #0) and (c^ in ['''','"']) then
        Quoted := c^;
      if (Quoted = #0) and (c^ in Separators) then
        begin
          AddString;
          inc (c);
          SkipWhitespace;
          b := c;
        end
      else
        inc (c);
    end;
  if (c <> b) then
    AddString;
end;



{ Point and rectangle constructors }

function Point(AX, AY: Integer): TPoint;

begin
  with Result do
  begin
    X := AX;
    Y := AY;
  end;
end;


function SmallPoint(AX, AY: SmallInt): TSmallPoint;

begin
  with Result do
  begin
    X := AX;
    Y := AY;
  end;
end;


function Rect(ALeft, ATop, ARight, ABottom: Integer): TRect;

begin
  with Result do
  begin
    Left := ALeft;
    Top := ATop;
    Right := ARight;
    Bottom := ABottom;
  end;
end;


function Bounds(ALeft, ATop, AWidth, AHeight: Integer): TRect;

begin
  with Result do
  begin
    Left := ALeft;
    Top := ATop;
    Right := ALeft + AWidth;
    Bottom :=  ATop + AHeight;
  end;
end;


function PointsEqual(const P1, P2: TPoint): Boolean; {$ifdef CLASSESINLINE}inline;{$endif CLASSESINLINE}
  begin
    { lazy, but should work }
    result:=QWord(P1)=QWord(P2);
  end;


function PointsEqual(const P1, P2: TSmallPoint): Boolean; {$ifdef CLASSESINLINE}inline;{$endif CLASSESINLINE}
  begin
    { lazy, but should work }
    result:=DWord(P1)=DWord(P2);
  end;

function InvalidPoint(X, Y: Integer): Boolean;
  begin
    result:=(X=-1) and (Y=-1);
  end;


function InvalidPoint(const At: TPoint): Boolean;
  begin
    result:=(At.x=-1) and (At.y=-1);
  end;


function InvalidPoint(const At: TSmallPoint): Boolean;
  begin
    result:=(At.x=-1) and (At.y=-1);
  end;


{ Object filing routines }

var
  IntConstList: TThreadList;

type
  TIntConst = class
    IntegerType: PTypeInfo;             // The integer type RTTI pointer
    IdentToIntFn: TIdentToInt;          // Identifier to Integer conversion
    IntToIdentFn: TIntToIdent;          // Integer to Identifier conversion
    constructor Create(AIntegerType: PTypeInfo; AIdentToInt: TIdentToInt;
      AIntToIdent: TIntToIdent);
  end;

constructor TIntConst.Create(AIntegerType: PTypeInfo; AIdentToInt: TIdentToInt;
  AIntToIdent: TIntToIdent);
begin
  IntegerType := AIntegerType;
  IdentToIntFn := AIdentToInt;
  IntToIdentFn := AIntToIdent;
end;

procedure RegisterIntegerConsts(IntegerType: Pointer; IdentToIntFn: TIdentToInt;
  IntToIdentFn: TIntToIdent);
begin
  IntConstList.Add(TIntConst.Create(IntegerType, IdentToIntFn, IntToIdentFn));
end;

function FindIntToIdent(AIntegerType: Pointer): TIntToIdent;
var
  i: Integer;
begin
  with IntConstList.LockList do
  try
    for i := 0 to Count - 1 do
      if TIntConst(Items[i]).IntegerType = AIntegerType then
        exit(TIntConst(Items[i]).IntToIdentFn);
    Result := nil;
  finally
    IntConstList.UnlockList;
  end;
end;

function FindIdentToInt(AIntegerType: Pointer): TIdentToInt;
var
  i: Integer;
begin
  with IntConstList.LockList do
  try
    for i := 0 to Count - 1 do
      with TIntConst(Items[I]) do
        if TIntConst(Items[I]).IntegerType = AIntegerType then
          exit(IdentToIntFn);
    Result := nil;
  finally
    IntConstList.UnlockList;
  end;
end;

function IdentToInt(const Ident: String; out Int: LongInt;
  const Map: array of TIdentMapEntry): Boolean;
var
  i: Integer;
begin
  for i := Low(Map) to High(Map) do
    if CompareText(Map[i].Name, Ident) = 0 then
    begin
      Int := Map[i].Value;
      exit(True);
    end;
  Result := False;
end;

function IntToIdent(Int: LongInt; var Ident: String;
  const Map: array of TIdentMapEntry): Boolean;
var
  i: Integer;
begin
  for i := Low(Map) to High(Map) do
    if Map[i].Value = Int then
    begin
      Ident := Map[i].Name;
      exit(True);
    end;
  Result := False;
end;

function GlobalIdentToInt(const Ident: String; var Int: LongInt):boolean;
var
  i : Integer;
begin
  with IntConstList.LockList do
    try
      for i := 0 to Count - 1 do
        if TIntConst(Items[I]).IdentToIntFn(Ident, Int) then
          Exit(True);
      Result := false;
    finally
      IntConstList.UnlockList;
    end;
end;

{ TPropFixup }
// Tainted. TPropFixup is being removed.

Type
  TInitHandler = Class(TObject)
    AHandler : TInitComponentHandler;
    AClass : TComponentClass;
  end;

{$ifndef i8086}
type
  TCodePtrList = TList;
{$endif i8086}

Var
  InitHandlerList : TList;
  FindGlobalComponentList : TCodePtrList;

procedure RegisterFindGlobalComponentProc(AFindGlobalComponent: TFindGlobalComponent);
  begin
    if not(assigned(FindGlobalComponentList)) then
      FindGlobalComponentList:=TCodePtrList.Create;
    if FindGlobalComponentList.IndexOf(CodePointer(AFindGlobalComponent))<0 then
      FindGlobalComponentList.Add(CodePointer(AFindGlobalComponent));
  end;


procedure UnregisterFindGlobalComponentProc(AFindGlobalComponent: TFindGlobalComponent);
  begin
    if assigned(FindGlobalComponentList) then
      FindGlobalComponentList.Remove(CodePointer(AFindGlobalComponent));
  end;


function FindGlobalComponent(const Name: string): TComponent;
  var
  	i : sizeint;
  begin
    FindGlobalComponent:=nil;
    if assigned(FindGlobalComponentList) then
      begin
      	for i:=FindGlobalComponentList.Count-1 downto 0 do
      	  begin
      	    FindGlobalComponent:=TFindGlobalComponent(FindGlobalComponentList[i])(name);
      	    if assigned(FindGlobalComponent) then
      	      break;
      	  end;
      end;
  end;


procedure RegisterInitComponentHandler(ComponentClass: TComponentClass;   Handler: TInitComponentHandler);
Var
  I : Integer;
  H: TInitHandler;
begin
  If (InitHandlerList=Nil) then
    InitHandlerList:=TList.Create;
  H:=TInitHandler.Create;
  H.Aclass:=ComponentClass;
  H.AHandler:=Handler;
  try
    With InitHandlerList do
      begin
        I:=0;
        While (I<Count) and not H.AClass.InheritsFrom(TInitHandler(Items[I]).AClass) do
          Inc(I);
        { override? }
        if (I<Count) and (TInitHandler(Items[I]).AClass=H.AClass) then
          begin
            TInitHandler(Items[I]).AHandler:=Handler;
            H.Free;
          end
        else
          InitHandlerList.Insert(I,H);
      end;
   except
     H.Free;
     raise;
  end;
end;


{ all targets should at least include the sysres.inc dummy in the system unit to compile this }
function CreateComponentfromRes(const res : string;Inst : THandle;var Component : TComponent) : Boolean;
  var
    ResStream : TResourceStream;
  begin
    result:=true;

    if Inst=0 then
      Inst:=HInstance;

    try
      ResStream:=TResourceStream.Create(Inst,res,RT_RCDATA);
      try
        Component:=ResStream.ReadComponent(Component);
      finally
        ResStream.Free;
      end;
    except
      on EResNotFound do
        result:=false;
    end;
  end;


function DefaultInitHandler(Instance: TComponent; RootAncestor: TClass): Boolean;

  function doinit(_class : TClass) : boolean;
    begin
      result:=false;
      if (_class.ClassType=TComponent) or (_class.ClassType=RootAncestor) then
        exit;
      result:=doinit(_class.ClassParent);
      result:=CreateComponentfromRes(_class.ClassName,0,Instance) or result;
    end;

  begin
{$ifdef FPC_HAS_FEATURE_THREADING}
    GlobalNameSpace.BeginWrite;
    try
{$endif}
      result:=doinit(Instance.ClassType);
{$ifdef FPC_HAS_FEATURE_THREADING}
    finally
      GlobalNameSpace.EndWrite;
    end;
{$endif}
  end;


function InitInheritedComponent(Instance: TComponent; RootAncestor: TClass): Boolean;
Var
  I : Integer;
begin
  I:=0;
  if not Assigned(InitHandlerList) then begin
    Result := True;
    Exit;
  end;
  Result:=False;
  With InitHandlerList do
    begin
    I:=0;
    // Instance is the normally the lowest one, so that one should be used when searching.
    While Not result and (I<Count) do
      begin
      If (Instance.InheritsFrom(TInitHandler(Items[i]).AClass)) then
        Result:=TInitHandler(Items[i]).AHandler(Instance,RootAncestor);
      Inc(I);
      end;
    end;
end;


function InitComponentRes(const ResName: String; Instance: TComponent): Boolean;

begin
  Result:=ReadComponentRes(ResName,Instance)=Instance;
end;

function SysReadComponentRes(HInstance : THandle; const ResName: String; Instance: TComponent): TComponent;

Var
  H : TFPResourceHandle;

begin
  { Windows unit also has a FindResource function, use the one from
    system unit here.  }
  H:=system.FindResource(HInstance,ResName,RT_RCDATA);
  if (PtrInt(H)=0) then
    Result:=Nil
  else
    With TResourceStream.Create(HInstance,ResName,RT_RCDATA) do
      try
        Result:=ReadComponent(Instance);
      Finally
        Free;
      end;
end;

function ReadComponentRes(const ResName: String; Instance: TComponent): TComponent;

begin
  Result:=SysReadComponentRes(Hinstance,Resname,Instance);
end;

function ReadComponentResEx(HInstance: THandle; const ResName: String): TComponent;

begin
  Result:=SysReadComponentRes(Hinstance,ResName,Nil);
end;


function ReadComponentResFile(const FileName: String; Instance: TComponent): TComponent;
var
  FileStream: TStream;
begin
  FileStream := TFileStream.Create(FileName, fmOpenRead {!!!:or fmShareDenyWrite});
  try
    Result := FileStream.ReadComponentRes(Instance);
  finally
    FileStream.Free;
  end;
end;


procedure WriteComponentResFile(const FileName: String; Instance: TComponent);
var
  FileStream: TStream;
begin
  FileStream := TFileStream.Create(FileName, fmCreate);
  try
    FileStream.WriteComponentRes(Instance.ClassName, Instance);
  finally
    FileStream.Free;
  end;
end;


Function FindNestedComponent(Root : TComponent; APath : String; CStyle : Boolean = True) : TComponent;

  Function GetNextName : String; {$ifdef CLASSESINLINE} inline; {$endif CLASSESINLINE}

  Var
    P : Integer;
    CM : Boolean;

  begin
    P:=Pos('.',APath);
    CM:=False;
    If (P=0) then
      begin
      If CStyle then
        begin
        P:=Pos('->',APath);
        CM:=P<>0;
        end;
      If (P=0) Then
        P:=Length(APath)+1;
      end;
    Result:=Copy(APath,1,P-1);
    Delete(APath,1,P+Ord(CM));
  end;

Var
  C : TComponent;
  S : String;
begin
  If (APath='') then
    Result:=Nil
  else
    begin
    Result:=Root;
    While (APath<>'') And (Result<>Nil) do
      begin
      C:=Result;
      S:=Uppercase(GetNextName);
      Result:=C.FindComponent(S);
      If (Result=Nil) And (S='OWNER') then
        Result:=C;
      end;
    end;
end;

{$ifdef FPC_HAS_FEATURE_THREADING}
threadvar
{$else}
var
{$endif}
  GlobalLoaded, GlobalLists: TFpList;

procedure BeginGlobalLoading;

begin
  if not Assigned(GlobalLists) then
    GlobalLists := TFpList.Create;
  GlobalLists.Add(GlobalLoaded);
  GlobalLoaded := TFpList.Create;
end;


{ Notify all global components that they have been loaded completely }
procedure NotifyGlobalLoading;
var
  i: Integer;
begin
  for i := 0 to GlobalLoaded.Count - 1 do
    TComponent(GlobalLoaded[i]).Loaded;
end;


procedure EndGlobalLoading;
begin
  { Free the memory occupied by BeginGlobalLoading }
  GlobalLoaded.Free;
  GlobalLoaded := TFpList(GlobalLists.Last);
  GlobalLists.Delete(GlobalLists.Count - 1);
  if GlobalLists.Count = 0 then
  begin
    GlobalLists.Free;
    GlobalLists := nil;
  end;
end;


function CollectionsEqual(C1, C2: TCollection): Boolean;
begin
  // !!!: Implement this
  CollectionsEqual:=false;
end;

function CollectionsEqual(C1, C2: TCollection; Owner1, Owner2: TComponent): Boolean;

  procedure stream_collection(s : tstream;c : tcollection;o : tcomponent);
    var
      w : twriter;
    begin
      w:=twriter.create(s,4096);
      try
        w.root:=o;
        w.flookuproot:=o;
        w.writecollection(c);
      finally
        w.free;
      end;
    end;

  var
    s1,s2 : tmemorystream;
  begin
    result:=false;
    if (c1.classtype<>c2.classtype) or
      (c1.count<>c2.count) then
      exit;
    if c1.count = 0 then
      begin
      result:= true;
      exit;
      end;
    s1:=tmemorystream.create;
    try
      s2:=tmemorystream.create;
      try
        stream_collection(s1,c1,owner1);
        stream_collection(s2,c2,owner2);
        result:=(s1.size=s2.size) and (CompareChar(s1.memory^,s2.memory^,s1.size)=0);
      finally
        s2.free;
      end;
    finally
      s1.free;
    end;
  end;


{ Object conversion routines }

type
  CharToOrdFuncty = Function(var charpo: Pointer): Cardinal;

function CharToOrd(var P: Pointer): Cardinal;
begin
  result:= ord(pchar(P)^);
  inc(pchar(P));
end;

function WideCharToOrd(var P: Pointer): Cardinal;
begin
  result:= ord(pwidechar(P)^);
  inc(pwidechar(P));
end;

function Utf8ToOrd(var P:Pointer): Cardinal;
begin
  // Should also check for illegal utf8 combinations
  Result := Ord(PChar(P)^);
  Inc(P);
  if (Result and $80) <> 0 then
    if (Ord(Result) and %11100000) = %11000000 then begin
      Result := ((Result and %00011111) shl 6)
                or (ord(PChar(P)^) and %00111111);
      Inc(P);
    end else if (Ord(Result) and %11110000) = %11100000 then begin
      Result := ((Result and %00011111) shl 12)
                or ((ord(PChar(P)^) and %00111111) shl 6)
                or (ord((PChar(P)+1)^) and %00111111);
      Inc(P,2);
    end else begin
      Result := ((ord(Result) and %00011111) shl 18)
                or ((ord(PChar(P)^) and %00111111) shl 12)
                or ((ord((PChar(P)+1)^) and %00111111) shl 6)
                or (ord((PChar(P)+2)^) and %00111111);
      Inc(P,3);
    end;
end;

procedure ObjectBinaryToText(Input, Output: TStream; Encoding: TObjectTextEncoding);

  procedure OutStr(s: String);
  begin
    if Length(s) > 0 then
      Output.Write(s[1], Length(s));
  end;

  procedure OutLn(s: String);
  begin
    OutStr(s + LineEnding);
  end;

  procedure Outchars(P, LastP : Pointer; CharToOrdFunc: CharToOrdFuncty;
    UseBytes: boolean = false);

  var
    res, NewStr: String;
    w: Cardinal;
    InString, NewInString: Boolean;
  begin
   if p = nil then begin
    res:= '''''';
   end
   else
    begin
    res := '';
    InString := False;
    while P < LastP do
      begin
      NewInString := InString;
      w := CharToOrdfunc(P);
      if w = ord('''') then
        begin //quote char
        if not InString then
          NewInString := True;
        NewStr := '''''';
        end
      else if (Ord(w) >= 32) and ((Ord(w) < 127) or (UseBytes and (Ord(w)<256))) then
        begin //printable ascii or bytes
        if not InString then
          NewInString := True;
        NewStr := char(w);
        end
      else
        begin //ascii control chars, non ascii
        if InString then
          NewInString := False;
        NewStr := '#' + IntToStr(w);
        end;
      if NewInString <> InString then
        begin
        NewStr := '''' + NewStr;
        InString := NewInString;
        end;
      res := res + NewStr;
      end;
    if InString then
      res := res + '''';
    end;
   OutStr(res);
  end;

  procedure OutString(s: String);
  begin
    OutChars(Pointer(S),PChar(S)+Length(S),@CharToOrd,Encoding=oteLFM);
  end;

  procedure OutWString(W: WideString);
  begin
    OutChars(Pointer(W),pwidechar(W)+Length(W),@WideCharToOrd);
  end;

  procedure OutUString(W: UnicodeString);
  begin
    OutChars(Pointer(W),pwidechar(W)+Length(W),@WideCharToOrd);
  end;

  procedure OutUtf8Str(s: String);
  begin
    if Encoding=oteLFM then
      OutChars(Pointer(S),PChar(S)+Length(S),@CharToOrd)
    else
      OutChars(Pointer(S),PChar(S)+Length(S),@Utf8ToOrd);
  end;

  function ReadWord : word; {$ifdef CLASSESINLINE}inline;{$endif CLASSESINLINE}
  begin
    Result:=Input.ReadWord;
    Result:=LEtoN(Result);
  end;

  function ReadDWord : longword; {$ifdef CLASSESINLINE}inline;{$endif CLASSESINLINE}
  begin
    Result:=Input.ReadDWord;
    Result:=LEtoN(Result);
  end;

  function ReadQWord : qword; {$ifdef CLASSESINLINE}inline;{$endif CLASSESINLINE}
  begin
    Input.ReadBuffer(Result,sizeof(Result));
    Result:=LEtoN(Result);
  end;

{$ifndef FPUNONE}
  {$IFNDEF FPC_HAS_TYPE_EXTENDED}
  function ExtendedToDouble(e : pointer) : double;
  var mant : qword;
      exp : smallint;
      sign : boolean;
      d : qword;
  begin
    move(pbyte(e)[0],mant,8); //mantissa         : bytes 0..7
    move(pbyte(e)[8],exp,2);  //exponent and sign: bytes 8..9
    mant:=LEtoN(mant);
    exp:=LetoN(word(exp));
    sign:=(exp and $8000)<>0;
    if sign then exp:=exp and $7FFF;
    case exp of
          0 : mant:=0;  //if denormalized, value is too small for double,
                        //so it's always zero
      $7FFF : exp:=2047 //either infinity or NaN
      else
      begin
        dec(exp,16383-1023);
        if (exp>=-51) and (exp<=0) then //can be denormalized
        begin
          mant:=mant shr (-exp);
          exp:=0;
        end
        else
        if (exp<-51) or (exp>2046) then //exponent too large.
        begin
          Result:=0;
          exit;
        end
        else //normalized value
          mant:=mant shl 1; //hide most significant bit
      end;
    end;
    d:=word(exp);
    d:=d shl 52;

    mant:=mant shr 12;
    d:=d or mant;
    if sign then d:=d or $8000000000000000;
    Result:=pdouble(@d)^;
  end;
  {$ENDIF}
{$endif}

  function ReadInt(ValueType: TValueType): Int64;
  begin
    case ValueType of
      vaInt8: Result := ShortInt(Input.ReadByte);
      vaInt16: Result := SmallInt(ReadWord);
      vaInt32: Result := LongInt(ReadDWord);
      vaInt64: Result := Int64(ReadQWord);
    end;
  end;

  function ReadInt: Int64;
  begin
    Result := ReadInt(TValueType(Input.ReadByte));
  end;

{$ifndef FPUNONE}
  function ReadExtended : extended;
  {$IFNDEF FPC_HAS_TYPE_EXTENDED}
  var ext : array[0..9] of byte;
  {$ENDIF}
  begin
    {$IFNDEF FPC_HAS_TYPE_EXTENDED}
    Input.ReadBuffer(ext[0],10);
    Result:=ExtendedToDouble(@(ext[0]));
    {$ELSE}
    Input.ReadBuffer(Result,sizeof(Result));
    {$ENDIF}
  end;
{$endif}

  function ReadSStr: String;
  var
    len: Byte;
  begin
    len := Input.ReadByte;
    SetLength(Result, len);
    if (len > 0) then
      Input.ReadBuffer(Result[1], len);
  end;

  function ReadLStr: String;
  var
    len: DWord;
  begin
    len := ReadDWord;
    SetLength(Result, len);
    if (len > 0) then
      Input.ReadBuffer(Result[1], len);
  end;

  function ReadWStr: WideString;
  var
    len: DWord;
  {$IFDEF ENDIAN_BIG}
    i : integer;
  {$ENDIF}
  begin
    len := ReadDWord;
    SetLength(Result, len);
    if (len > 0) then
    begin
      Input.ReadBuffer(Pointer(@Result[1])^, len*2);
      {$IFDEF ENDIAN_BIG}
      for i:=1 to len do
        Result[i]:=widechar(SwapEndian(word(Result[i])));
      {$ENDIF}
    end;
  end;

  function ReadUStr: UnicodeString;
  var
    len: DWord;
  {$IFDEF ENDIAN_BIG}
    i : integer;
  {$ENDIF}
  begin
    len := ReadDWord;
    SetLength(Result, len);
    if (len > 0) then
    begin
      Input.ReadBuffer(Pointer(@Result[1])^, len*2);
      {$IFDEF ENDIAN_BIG}
      for i:=1 to len do
        Result[i]:=widechar(SwapEndian(word(Result[i])));
      {$ENDIF}
    end;
  end;

  procedure ReadPropList(indent: String);

    procedure ProcessValue(ValueType: TValueType; Indent: String);

      procedure ProcessBinary;
      var
        ToDo, DoNow, i: LongInt;
        lbuf: array[0..31] of Byte;
        s: String;
      begin
        ToDo := ReadDWord;
        OutLn('{');
        while ToDo > 0 do begin
          DoNow := ToDo;
          if DoNow > 32 then DoNow := 32;
          Dec(ToDo, DoNow);
          s := Indent + '  ';
          Input.ReadBuffer(lbuf, DoNow);
          for i := 0 to DoNow - 1 do
            s := s + IntToHex(lbuf[i], 2);
          OutLn(s);
        end;
        OutLn(indent + '}');
      end;

    var
      s: String;
{      len: LongInt; }
      IsFirst: Boolean;
{$ifndef FPUNONE}
      ext: Extended;
{$endif}

    begin
      case ValueType of
        vaList: begin
            OutStr('(');
            IsFirst := True;
            while True do begin
              ValueType := TValueType(Input.ReadByte);
              if ValueType = vaNull then break;
              if IsFirst then begin
                OutLn('');
                IsFirst := False;
              end;
              OutStr(Indent + '  ');
              ProcessValue(ValueType, Indent + '  ');
            end;
            OutLn(Indent + ')');
          end;
        vaInt8: OutLn(IntToStr(ShortInt(Input.ReadByte)));
        vaInt16: OutLn( IntToStr(SmallInt(ReadWord)));
        vaInt32: OutLn(IntToStr(LongInt(ReadDWord)));
        vaInt64: OutLn(IntToStr(Int64(ReadQWord)));
{$ifndef FPUNONE}
        vaExtended: begin
            ext:=ReadExtended;
            Str(ext,S);// Do not use localized strings.
            OutLn(S);
          end;
{$endif}
        vaString: begin
            OutString(ReadSStr);
            OutLn('');
          end;
        vaIdent: OutLn(ReadSStr);
        vaFalse: OutLn('False');
        vaTrue: OutLn('True');
        vaBinary: ProcessBinary;
        vaSet: begin
            OutStr('[');
            IsFirst := True;
            while True do begin
              s := ReadSStr;
              if Length(s) = 0 then break;
              if not IsFirst then OutStr(', ');
              IsFirst := False;
              OutStr(s);
            end;
            OutLn(']');
          end;
        vaLString:
          begin
          OutString(ReadLStr);
          OutLn('');
          end;
        vaWString:
          begin
          OutWString(ReadWStr);
          OutLn('');
          end;
        vaUString:
          begin
          OutWString(ReadWStr);
          OutLn('');
          end;
        vaNil:
          OutLn('nil');
        vaCollection: begin
            OutStr('<');
            while Input.ReadByte <> 0 do begin
              OutLn(Indent);
              Input.Seek(-1, soFromCurrent);
              OutStr(indent + '  item');
              ValueType := TValueType(Input.ReadByte);
              if ValueType <> vaList then
                OutStr('[' + IntToStr(ReadInt(ValueType)) + ']');
              OutLn('');
              ReadPropList(indent + '    ');
              OutStr(indent + '  end');
            end;
            OutLn('>');
          end;
        {vaSingle: begin OutLn('!!Single!!'); exit end;
        vaCurrency: begin OutLn('!!Currency!!'); exit end;
        vaDate: begin OutLn('!!Date!!'); exit end;}
        vaUTF8String: begin
            OutUtf8Str(ReadLStr);
            OutLn('');
          end;
        else
          Raise EReadError.CreateFmt(SErrInvalidPropertyType,[Ord(ValueType)]);
      end;
    end;

  begin
    while Input.ReadByte <> 0 do begin
      Input.Seek(-1, soFromCurrent);
      OutStr(indent + ReadSStr + ' = ');
      ProcessValue(TValueType(Input.ReadByte), Indent);
    end;
  end;

  procedure ReadObject(indent: String);
  var
    b: Byte;
    ObjClassName, ObjName: String;
    ChildPos: LongInt;
  begin
    // Check for FilerFlags
    b := Input.ReadByte;
    if (b and $f0) = $f0 then begin
      if (b and 2) <> 0 then ChildPos := ReadInt;
    end else begin
      b := 0;
      Input.Seek(-1, soFromCurrent);
    end;

    ObjClassName := ReadSStr;
    ObjName := ReadSStr;

    OutStr(Indent);
    if (b and 1) <> 0 then OutStr('inherited')
    else
     if (b and 4) <> 0 then OutStr('inline')
     else OutStr('object');
    OutStr(' ');
    if ObjName <> '' then
      OutStr(ObjName + ': ');
    OutStr(ObjClassName);
    if (b and 2) <> 0 then OutStr('[' + IntToStr(ChildPos) + ']');
    OutLn('');

    ReadPropList(indent + '  ');

    while Input.ReadByte <> 0 do begin
      Input.Seek(-1, soFromCurrent);
      ReadObject(indent + '  ');
    end;
    OutLn(indent + 'end');
  end;

type
  PLongWord = ^LongWord;
const
  signature: PChar = 'TPF0';

begin
  if Input.ReadDWord <> PLongWord(Pointer(signature))^ then
    raise EReadError.Create('Illegal stream image' {###SInvalidImage});
  ReadObject('');
end;

procedure ObjectBinaryToText(Input, Output: TStream);
begin
  ObjectBinaryToText(Input,Output,oteDFM);
end;

procedure ObjectTextToBinary(Input, Output: TStream);
var
  parser: TParser;

  procedure WriteWord(w : word); {$ifdef CLASSESINLINE}inline;{$endif CLASSESINLINE}
  begin
    w:=NtoLE(w);
    Output.WriteWord(w);
  end;

  procedure WriteDWord(lw : longword); {$ifdef CLASSESINLINE}inline;{$endif CLASSESINLINE}
  begin
    lw:=NtoLE(lw);
    Output.WriteDWord(lw);
  end;

  procedure WriteQWord(qw : qword); {$ifdef CLASSESINLINE}inline;{$endif CLASSESINLINE}
  begin
    qw:=NtoLE(qw);
    Output.WriteBuffer(qw,sizeof(qword));
  end;

{$ifndef FPUNONE}
  {$IFNDEF FPC_HAS_TYPE_EXTENDED}
  procedure DoubleToExtended(d : double; e : pointer);
  var mant : qword;
      exp : smallint;
      sign : boolean;
  begin
    mant:=(qword(d) and $000FFFFFFFFFFFFF) shl 12;
    exp :=(qword(d) shr 52) and $7FF;
    sign:=(qword(d) and $8000000000000000)<>0;
    case exp of
         0 : begin
               if mant<>0 then  //denormalized value: hidden bit is 0. normalize it
               begin
                 exp:=16383-1022;
                 while (mant and $8000000000000000)=0 do
                 begin
                   dec(exp);
                   mant:=mant shl 1;
                 end;
                 dec(exp); //don't shift, most significant bit is not hidden in extended
               end;
             end;
      2047 : exp:=$7FFF //either infinity or NaN
      else
      begin
        inc(exp,16383-1023);
        mant:=(mant shr 1) or $8000000000000000; //unhide hidden bit
      end;
    end;
    if sign then exp:=exp or $8000;
    mant:=NtoLE(mant);
    exp:=NtoLE(word(exp));
    move(mant,pbyte(e)[0],8); //mantissa         : bytes 0..7
    move(exp,pbyte(e)[8],2);  //exponent and sign: bytes 8..9
  end;
  {$ENDIF}

  procedure WriteExtended(e : extended);
  {$IFNDEF FPC_HAS_TYPE_EXTENDED}
  var ext : array[0..9] of byte;
  {$ENDIF}
  begin
    {$IFNDEF FPC_HAS_TYPE_EXTENDED}
    DoubleToExtended(e,@(ext[0]));
    Output.WriteBuffer(ext[0],10);
    {$ELSE}
    Output.WriteBuffer(e,sizeof(e));
    {$ENDIF}
  end;
{$endif}

  procedure WriteString(s: String);
  var size : byte;
  begin
    if length(s)>255 then size:=255
    else size:=length(s);
    Output.WriteByte(size);
    if Length(s) > 0 then
      Output.WriteBuffer(s[1], size);
  end;

  procedure WriteLString(Const s: String);
  begin
    WriteDWord(Length(s));
    if Length(s) > 0 then
      Output.WriteBuffer(s[1], Length(s));
  end;

  procedure WriteWString(Const s: WideString);
  var len : longword;
  {$IFDEF ENDIAN_BIG}
      i : integer;
      ws : widestring;
  {$ENDIF}
  begin
    len:=Length(s);
    WriteDWord(len);
    if len > 0 then
    begin
      {$IFDEF ENDIAN_BIG}
      setlength(ws,len);
      for i:=1 to len do
        ws[i]:=widechar(SwapEndian(word(s[i])));
      Output.WriteBuffer(ws[1], len*sizeof(widechar));
      {$ELSE}
      Output.WriteBuffer(s[1], len*sizeof(widechar));
      {$ENDIF}
    end;
  end;

  procedure WriteInteger(value: Int64);
  begin
    if (value >= -128) and (value <= 127) then begin
      Output.WriteByte(Ord(vaInt8));
      Output.WriteByte(byte(value));
    end else if (value >= -32768) and (value <= 32767) then begin
      Output.WriteByte(Ord(vaInt16));
      WriteWord(word(value));
    end else if (value >= -2147483648) and (value <= 2147483647) then begin
      Output.WriteByte(Ord(vaInt32));
      WriteDWord(longword(value));
    end else begin
      Output.WriteByte(ord(vaInt64));
      WriteQWord(qword(value));
    end;
  end;

  procedure ProcessWideString(const left : widestring);
  var ws : widestring;
  begin
    ws:=left+parser.TokenWideString;
    while parser.NextToken = '+' do
    begin
      parser.NextToken;   // Get next string fragment
      if not (parser.Token in [toString,toWString]) then
        parser.CheckToken(toWString);
      ws:=ws+parser.TokenWideString;
    end;
    Output.WriteByte(Ord(vaWstring));
    WriteWString(ws);
  end;

  procedure ProcessProperty; forward;

  procedure ProcessValue;
  var
{$ifndef FPUNONE}
    flt: Extended;
{$endif}
    s: String;
    stream: TMemoryStream;
  begin
    case parser.Token of
      toInteger:
        begin
          WriteInteger(parser.TokenInt);
          parser.NextToken;
        end;
{$ifndef FPUNONE}
      toFloat:
        begin
          Output.WriteByte(Ord(vaExtended));
          flt := Parser.TokenFloat;
          WriteExtended(flt);
          parser.NextToken;
        end;
{$endif}
      toString:
        begin
          s := parser.TokenString;
          while parser.NextToken = '+' do
          begin
            parser.NextToken;   // Get next string fragment
            case parser.Token of
              toString  : s:=s+parser.TokenString;
              toWString : begin
                            ProcessWideString(WideString(s));
                            exit;
                          end
              else parser.CheckToken(toString);
            end;
          end;
          if (length(S)>255) then
          begin
            Output.WriteByte(Ord(vaLString));
            WriteLString(S);
          end
          else
          begin
            Output.WriteByte(Ord(vaString));
            WriteString(s);
          end;
        end;
      toWString:
        ProcessWideString('');
      toSymbol:
        begin
          if CompareText(parser.TokenString, 'True') = 0 then
            Output.WriteByte(Ord(vaTrue))
          else if CompareText(parser.TokenString, 'False') = 0 then
            Output.WriteByte(Ord(vaFalse))
          else if CompareText(parser.TokenString, 'nil') = 0 then
            Output.WriteByte(Ord(vaNil))
          else
          begin
            Output.WriteByte(Ord(vaIdent));
            WriteString(parser.TokenComponentIdent);
          end;
          Parser.NextToken;
        end;
      // Set
      '[':
        begin
          parser.NextToken;
          Output.WriteByte(Ord(vaSet));
          if parser.Token <> ']' then
            while True do
            begin
              parser.CheckToken(toSymbol);
              WriteString(parser.TokenString);
              parser.NextToken;
              if parser.Token = ']' then
                break;
              parser.CheckToken(',');
              parser.NextToken;
            end;
          Output.WriteByte(0);
          parser.NextToken;
        end;
      // List
      '(':
        begin
          parser.NextToken;
          Output.WriteByte(Ord(vaList));
          while parser.Token <> ')' do
            ProcessValue;
          Output.WriteByte(0);
          parser.NextToken;
        end;
      // Collection
      '<':
        begin
          parser.NextToken;
          Output.WriteByte(Ord(vaCollection));
          while parser.Token <> '>' do
          begin
            parser.CheckTokenSymbol('item');
            parser.NextToken;
            // ConvertOrder
            Output.WriteByte(Ord(vaList));
            while not parser.TokenSymbolIs('end') do
              ProcessProperty;
            parser.NextToken;   // Skip 'end'
            Output.WriteByte(0);
          end;
          Output.WriteByte(0);
          parser.NextToken;
        end;
      // Binary data
      '{':
        begin
          Output.WriteByte(Ord(vaBinary));
          stream := TMemoryStream.Create;
          try
            parser.HexToBinary(stream);
            WriteDWord(stream.Size);
            Output.WriteBuffer(Stream.Memory^, stream.Size);
          finally
            stream.Free;
          end;
          parser.NextToken;
        end;
      else
        parser.Error(SInvalidProperty);
    end;
  end;

  procedure ProcessProperty;
  var
    name: String;
  begin
    // Get name of property
    parser.CheckToken(toSymbol);
    name := parser.TokenString;
    while True do begin
      parser.NextToken;
      if parser.Token <> '.' then break;
      parser.NextToken;
      parser.CheckToken(toSymbol);
      name := name + '.' + parser.TokenString;
    end;
    WriteString(name);
    parser.CheckToken('=');
    parser.NextToken;
    ProcessValue;
  end;

  procedure ProcessObject;
  var
    Flags: Byte;
    ObjectName, ObjectType: String;
    ChildPos: Integer;
  begin
    if parser.TokenSymbolIs('OBJECT') then
      Flags :=0  { IsInherited := False }
    else begin
      if parser.TokenSymbolIs('INHERITED') then
        Flags := 1 { IsInherited := True; }
      else begin
        parser.CheckTokenSymbol('INLINE');
        Flags := 4;
      end;
    end;
    parser.NextToken;
    parser.CheckToken(toSymbol);
    ObjectName := '';
    ObjectType := parser.TokenString;
    parser.NextToken;
    if parser.Token = ':' then begin
      parser.NextToken;
      parser.CheckToken(toSymbol);
      ObjectName := ObjectType;
      ObjectType := parser.TokenString;
      parser.NextToken;
      if parser.Token = '[' then begin
        parser.NextToken;
        ChildPos := parser.TokenInt;
        parser.NextToken;
        parser.CheckToken(']');
        parser.NextToken;
        Flags := Flags or 2;
      end;
    end;
    if Flags <> 0 then begin
      Output.WriteByte($f0 or Flags);
      if (Flags and 2) <> 0 then
        WriteInteger(ChildPos);
    end;
    WriteString(ObjectType);
    WriteString(ObjectName);

    // Convert property list
    while not (parser.TokenSymbolIs('END') or
      parser.TokenSymbolIs('OBJECT') or
      parser.TokenSymbolIs('INHERITED') or
      parser.TokenSymbolIs('INLINE')) do
      ProcessProperty;
    Output.WriteByte(0);        // Terminate property list

    // Convert child objects
    while not parser.TokenSymbolIs('END') do ProcessObject;
    parser.NextToken;           // Skip end token
    Output.WriteByte(0);        // Terminate property list
  end;

const
  signature: PChar = 'TPF0';
begin
  parser := TParser.Create(Input);
  try
    Output.WriteBuffer(signature[0], 4);
    ProcessObject;
  finally
    parser.Free;
  end;
end;


procedure ObjectResourceToText(Input, Output: TStream);
begin
  Input.ReadResHeader;
  ObjectBinaryToText(Input, Output);
end;


procedure ObjectTextToResource(Input, Output: TStream);
var
  StartPos, FixupInfo: LongInt;
  parser: TParser;
  name: String;
begin
  // Get form type name
  StartPos := Input.Position;
  parser := TParser.Create(Input);
  try
    if not parser.TokenSymbolIs('OBJECT') then parser.CheckTokenSymbol('INHERITED');
    parser.NextToken;
    parser.CheckToken(toSymbol);
    parser.NextToken;
    parser.CheckToken(':');
    parser.NextToken;
    parser.CheckToken(toSymbol);
    name := parser.TokenString;
  finally
    parser.Free;
    Input.Position := StartPos;
  end;

  name := UpperCase(name);
  Output.WriteResourceHeader(name,FixupInfo); // Write resource header
  ObjectTextToBinary(Input, Output);          // Convert the stuff!
  Output.FixupResourceHeader(FixupInfo);      // Insert real resource data size
end;



{ Utility routines }

function LineStart(Buffer, BufPos: PChar): PChar;

begin
  Result := BufPos;
  while Result > Buffer do begin
    Dec(Result);
    if Result[0] = #10 then break;
  end;
end;

procedure CommonInit;
begin
{$ifdef FPC_HAS_FEATURE_THREADING}
  SynchronizeTimeoutEvent:=RtlEventCreate;
  InterlockedIncrement(ThreadQueueLockCounter);
  InitCriticalSection(ThreadQueueLock);
  MainThreadID:=GetCurrentThreadID;
{$else}
  MainThreadID:=0{GetCurrentThreadID};
{$endif}
  ExternalThreads := TThreadList.Create;
{$ifdef FPC_HAS_FEATURE_THREADING}
  InitCriticalsection(ResolveSection);
  TThread.FProcessorCount := CPUCount;
{$else}
  TThread.FProcessorCount := 1{CPUCount};
{$endif}
  InitHandlerList:=Nil;
  FindGlobalComponentList:=nil;
  IntConstList := TThreadList.Create;
  ClassList := TThreadList.Create;
  ClassAliasList := TStringList.Create;
  { on unix this maps to a simple rw synchornizer }
  GlobalNameSpace := TMultiReadExclusiveWriteSynchronizer.Create;
  RegisterInitComponentHandler(TComponent,@DefaultInitHandler);
end;

procedure CommonCleanup;
var
  i: Integer;
  tmpentry: TThread.PThreadQueueEntry;
begin
{$ifdef FPC_HAS_FEATURE_THREADING}
  GlobalNameSpace.BeginWrite;
{$endif}
  with IntConstList.LockList do
    try
      for i := 0 to Count - 1 do
        TIntConst(Items[I]).Free;
    finally
      IntConstList.UnlockList;
    end;
    IntConstList.Free;
  ClassList.Free;
  ClassAliasList.Free;
  RemoveFixupReferences(nil, '');
{$ifdef FPC_HAS_FEATURE_THREADING}
  DoneCriticalsection(ResolveSection);
{$endif}
  GlobalLists.Free;
  ComponentPages.Free;
  FreeAndNil(NeedResolving);
  { GlobalNameSpace is an interface so this is enough }
  GlobalNameSpace:=nil;

  if (InitHandlerList<>Nil) then
    for i := 0 to InitHandlerList.Count - 1 do
      TInitHandler(InitHandlerList.Items[I]).Free;
  InitHandlerList.Free;
  InitHandlerList:=Nil;
  FindGlobalComponentList.Free;
  FindGlobalComponentList:=nil;
  ExternalThreadsCleanup:=True;
  with ExternalThreads.LockList do
    try
      for i := 0 to Count - 1 do
        TThread(Items[i]).Free;
    finally
      ExternalThreads.UnlockList;
    end;
  FreeAndNil(ExternalThreads);
{$ifdef FPC_HAS_FEATURE_THREADING}
  RtlEventDestroy(SynchronizeTimeoutEvent);
  try
    System.EnterCriticalSection(ThreadQueueLock);
{$endif}
  { clean up the queue, but keep in mind that the entries used for Synchronize
    are owned by the corresponding TThread }
    while Assigned(ThreadQueueHead) do begin
      tmpentry := ThreadQueueHead;
      ThreadQueueHead := tmpentry^.Next;
      if not Assigned(tmpentry^.SyncEvent) then
        Dispose(tmpentry);
    end;
    { We also need to reset ThreadQueueTail }
    ThreadQueueTail := nil;
{$ifdef FPC_HAS_FEATURE_THREADING}
  finally
    System.LeaveCriticalSection(ThreadQueueLock);
  end;
  if InterlockedDecrement(ThreadQueueLockCounter)=0 then
    DoneCriticalSection(ThreadQueueLock);
{$endif}
end;

{ TFiler implementation }
{$i filer.inc}

{ TReader implementation }
{$i reader.inc}

{ TWriter implementations }
{$i writer.inc}
{$i twriter.inc}