TGWin32ProxyBase Class Reference

Proxy classes provide thread-safe interface to global objects.

For example: TGWin32VirtualXProxy (to gVirtualX).

Proxy object creates callback object and posts a windows message to "processing thread". When windows message is received callback ("real method") is executed.

For example: gVirtualX->ClearWindow()

• callback object created containing pointer to function corresponding TGWin32::ClearWindow() method
• message to "processing thread" (main thread) is posted
• TGWin32::ClearWindow() method is executed inside main thread
• thread containing gVirtualX proxy object waits for reply from main thread that TGWin32::ClearWindow() is completed.

Howto create proxy class:

1. Naming. name of proxy = TGWin32 + the name of "virtual base class" + Proxy

   e.g. TGWin32VirtualXProxy = TGWin32 + VirtualX + Proxy

2. Definition of global object As example check definition and implementation of gVirtualX global object

3. Class definition. proxy class must be inherited from "virtual base class" and TGWin32ProxyBase class. For example:

   class TGWin32VirtualX : public TVirtualX , public TGWin32ProxyBase

4. Constructors, destructor, extra methods.

   • constructors and destructor of proxy class do nothing
   • proxy class must contain two extra static methods RealObject(), ProxyObject(). Each of them return pointer to object of virtual base class.

   For example: static TVirtualX *RealObject(); static TVirtualX *ProxyObject();

5. Implementation TGWin32ProxyDefs.h file contains a set of macros which very simplify implementation.
   • RETURN_PROXY_OBJECT macro implements ProxyObject() method, e.g. RETURN_PROXY_OBJECT(VirtualX)

   • the names of other macros say about itself.

     For example: VOID_METHOD_ARG0(VirtualX,SetFillAttributes,1) void TGWin32VirtualXProxy::SetFillAttributes()

     RETURN_METHOD_ARG0_CONST(VirtualX,Visual_t,GetVisual) Visual_t TGWin32VirtualXProxy::GetVisual() const

     RETURN_METHOD_ARG2(VirtualX,Int_t,OpenPixmap,UInt_t,w,UInt_t,h) Int_t TGWin32VirtualXProxy::OpenPixmap,UInt_t w,UInt_t h)

Definition at line 22 of file TGWin32ProxyBase.h.

Public Member Functions
	TGWin32ProxyBase ()
	ctor
virtual	~TGWin32ProxyBase ()
	dtor
virtual void	ExecuteCallBack (Bool_t sync)
	Executes all batched callbacks and the latest callback This method is executed by server thread.
ULong_t	GetId () const
virtual Double_t	GetMilliSeconds ()
	returns elapsed time in milliseconds with microseconds precision

Static Public Member Functions
static void	GlobalLock ()
	lock any proxy (client thread)
static void	GlobalUnlock ()
	unlock any proxy (client thread)
static Bool_t	IsGloballyLocked ()
	Check the status of the lock.
static void	Lock ()
	enter critical section
static Bool_t	Ping ()
	send ping messsage to server thread
static void	Unlock ()
	leave critical section

Static Public Attributes
static ULong_t	fgMainThreadId = 0
	main thread ID
static ULong_t	fgPingMessageId = 0
	ping message ID
static ULong_t	fgPostMessageId = 0
	post message ID
static ULong_t	fgUserThreadId = 0
	user (e.g. python) thread ID

Protected Member Functions
virtual Bool_t	ForwardCallBack (Bool_t sync)
	if sync is kTRUE:
virtual void	SendExitMessage ()
	send exit message to server thread

Protected Attributes
Int_t	fBatchLimit
	batch limit
TGWin32CallBack	fCallBack
	callback function (executed by "main" thread)
ULong_t	fId
	thread id. There is one proxy per client thread
Bool_t	fIsVirtualX
	true if actual TVirtualX implementation
TList *	fListOfCallBacks
	list of callbacks (used for batch processing)
void *	fParam
	arguments passed to/from callback function
TGWin32ProxyBasePrivate *	fPimpl
	very private data

Static Protected Attributes
static Long_t	fgLock = 0
	fgLock=1 - all client threads locked
static UInt_t	fMaxResponseTime = 0
	max period for waiting response from server thread

Friends
class	TGWin32
class	TGWin32GL

#include <TGWin32ProxyBase.h>

Inheritance diagram for TGWin32ProxyBase:

Constructor & Destructor Documentation

TGWin32ProxyBase()

TGWin32ProxyBase::TGWin32ProxyBase

(

)

ctor

Definition at line 136 of file TGWin32ProxyBase.cxx.

~TGWin32ProxyBase()

TGWin32ProxyBase::~TGWin32ProxyBase ( )

virtual

dtor

Definition at line 153 of file TGWin32ProxyBase.cxx.

Member Function Documentation

ExecuteCallBack()

void TGWin32ProxyBase::ExecuteCallBack ( Bool_t sync )

virtual

Executes all batched callbacks and the latest callback This method is executed by server thread.

Definition at line 235 of file TGWin32ProxyBase.cxx.

ForwardCallBack()

Bool_t TGWin32ProxyBase::ForwardCallBack ( Bool_t sync )

protectedvirtual

if sync is kTRUE:

• post message to main thread.
• execute callbacks from fListOfCallBacks
• wait for response else
• add callback to fListOfCallBacks

returns kTRUE if callback execution is delayed (batched)

Definition at line 262 of file TGWin32ProxyBase.cxx.

GetId()

ULong_t TGWin32ProxyBase::GetId ( ) const

inline

Definition at line 58 of file TGWin32ProxyBase.h.

GetMilliSeconds()

Double_t TGWin32ProxyBase::GetMilliSeconds ( )

virtual

returns elapsed time in milliseconds with microseconds precision

Definition at line 207 of file TGWin32ProxyBase.cxx.

GlobalLock()

void TGWin32ProxyBase::GlobalLock ( )

static

lock any proxy (client thread)

Definition at line 181 of file TGWin32ProxyBase.cxx.

GlobalUnlock()

void TGWin32ProxyBase::GlobalUnlock ( )

static

unlock any proxy (client thread)

Definition at line 190 of file TGWin32ProxyBase.cxx.

IsGloballyLocked()

Bool_t TGWin32ProxyBase::IsGloballyLocked ( )

static

Check the status of the lock.

Definition at line 327 of file TGWin32ProxyBase.cxx.

Lock()

void TGWin32ProxyBase::Lock ( )

static

enter critical section

Definition at line 165 of file TGWin32ProxyBase.cxx.

Ping()

Bool_t TGWin32ProxyBase::Ping ( )

static

send ping messsage to server thread

Definition at line 199 of file TGWin32ProxyBase.cxx.

SendExitMessage()

void TGWin32ProxyBase::SendExitMessage ( )

protectedvirtual

send exit message to server thread

Definition at line 335 of file TGWin32ProxyBase.cxx.

Unlock()

void TGWin32ProxyBase::Unlock ( )

static

leave critical section

Definition at line 173 of file TGWin32ProxyBase.cxx.

Friends And Related Symbol Documentation

TGWin32

friend class TGWin32

friend

Definition at line 23 of file TGWin32ProxyBase.h.

TGWin32GL

friend class TGWin32GL

friend

Definition at line 24 of file TGWin32ProxyBase.h.

Member Data Documentation

fBatchLimit

Int_t TGWin32ProxyBase::fBatchLimit

protected

batch limit

Definition at line 28 of file TGWin32ProxyBase.h.

fCallBack

TGWin32CallBack TGWin32ProxyBase::fCallBack

protected

callback function (executed by "main" thread)

Definition at line 30 of file TGWin32ProxyBase.h.

fgLock

Long_t TGWin32ProxyBase::fgLock = 0

staticprotected

fgLock=1 - all client threads locked

Definition at line 35 of file TGWin32ProxyBase.h.

fgMainThreadId

ULong_t TGWin32ProxyBase::fgMainThreadId = 0

static

main thread ID

Definition at line 43 of file TGWin32ProxyBase.h.

fgPingMessageId

ULong_t TGWin32ProxyBase::fgPingMessageId = 0

static

ping message ID

Definition at line 42 of file TGWin32ProxyBase.h.

fgPostMessageId

ULong_t TGWin32ProxyBase::fgPostMessageId = 0

static

post message ID

Definition at line 41 of file TGWin32ProxyBase.h.

fgUserThreadId

ULong_t TGWin32ProxyBase::fgUserThreadId = 0

static

user (e.g. python) thread ID

Definition at line 44 of file TGWin32ProxyBase.h.

fId

ULong_t TGWin32ProxyBase::fId

protected

thread id. There is one proxy per client thread

Definition at line 32 of file TGWin32ProxyBase.h.

fIsVirtualX

Bool_t TGWin32ProxyBase::fIsVirtualX

protected

true if actual TVirtualX implementation

Definition at line 33 of file TGWin32ProxyBase.h.

fListOfCallBacks

TList* TGWin32ProxyBase::fListOfCallBacks

protected

list of callbacks (used for batch processing)

Definition at line 29 of file TGWin32ProxyBase.h.

fMaxResponseTime

UInt_t TGWin32ProxyBase::fMaxResponseTime = 0

staticprotected

max period for waiting response from server thread

Definition at line 34 of file TGWin32ProxyBase.h.

fParam

void* TGWin32ProxyBase::fParam

protected

arguments passed to/from callback function

Definition at line 31 of file TGWin32ProxyBase.h.

fPimpl

TGWin32ProxyBasePrivate* TGWin32ProxyBase::fPimpl

protected

very private data

Definition at line 27 of file TGWin32ProxyBase.h.