HelperInterface.h

//========================================================================================
// 
// $File$
// 
// Owner: Robin_Briggs
// 
// $Author$
// 
// $DateTime$
// 
// $Revision$
// 
// $Change$
// 
// Copyright 1997-2010 Adobe Systems Incorporated. All rights reserved.
// 
// NOTICE: Adobe permits you to use, modify, and distribute this file in accordance 
// with the terms of the Adobe license agreement accompanying it. If you have received
// this file from a source other than Adobe, then your use, modification, or 
// distribution of it requires the prior written permission of Adobe.
// 
// 
// The purpose of HelperInterface is to make it easier to define
// the functions from IPMUnknown that are required for every interface.
// HelperInterface defines a class, HelperInterface, that implements
// QueryInterface, AddRef, and Release. HelperInterface is designed to
// be included in the implementation class of an interface as a member
// variable. HelperInterface defines a set of macros that allow a
// mapping from the QueryInterface, AddRef, and Release in the implementation
// class, and the ones in HelperInterface.
// 
// How to use HelperInterface:
// 1. In the class's declaration, include DECLARE_HELPER_METHODS.
// 2. Where the class is defined, include DEFINE_HELPER_METHODS.
// 3. In the constructor for the class, include INIT_HELPER_METHODS.
// 
// Example:
// class Foo : public IFoo {
// public:
// Foo(IPMUnknown *boss);
// void Bar();
// 
// 
// DEFINE_HELPER_METHODS(Foo)
// 
// Foo :: Foo(IPMUnknown *boss) :
// INIT_HELPER_METHODS(boss)
// 
//========================================================================================

#ifndef __HelperInterface__
#define __HelperInterface__

#include "InterfaceFactory.h"
#include "IPMPersist.h"
#include "PersistUtils.h"
#include "IViewObjectChanges.h"
#include "IControllingUnknown.h"
#include "DBChangesMonitorDisabler.h"
class ObjectModel;

class HelperInterface
{
 friend class ObjectModelBase;

public:
 HelperInterface(IPMUnknown *boss) :
#ifdef DEBUG
 fInterfaceRefCount(0),
#endif
 fBoss(boss)
 {}

 IPMUnknown *QueryInterface(PMIID interfaceID) const
 {
#if DEBUG
 if (interfaceID == IID_IINTERFACEREFCOUNT)
 return (IPMUnknown *)fInterfaceRefCount;
#endif
 if (interfaceID == IID_ICONTROLLINGUNKNOWN && fBoss)
 {
 fBoss->AddRef();
 return fBoss;
 }

 return fBoss ? fBoss->QueryInterface(interfaceID) : nil;
 }
 void AddRef() const
 {
 if (fBoss)
 {
#if DEBUG
 fInterfaceRefCount++;
#endif
 fBoss->AddRef();
 }
 }
 void Release() const
 {
 if (fBoss)
 {
#if DEBUG
 fInterfaceRefCount--;
#endif
 fBoss->Release();
 }
 }

 IControllingUnknown *GetBoss()
 {
 return static_cast<IControllingUnknown*>(fBoss);
 }

private:
 IPMUnknown *fBoss;

 void SetBoss(IPMUnknown *boss)
 { fBoss = boss; }

#ifdef DEBUG
public:
 void AddRef(IPMUnknown* whichInterface) const
 { if (fBoss) ((IControllingUnknown*)fBoss)->DebugAddRef(whichInterface); }
 void Release(IPMUnknown* whichInterface) const
 { if (fBoss) ((IControllingUnknown*)fBoss)->DebugRelease(whichInterface); }
 // This is here for debugging. Most bosses are PMControllingUnknown,
 // but that's not guaranteed.
 mutable size_t fInterfaceRefCount;
#endif
};


#define \
public: \
 IPMUnknown *QueryInterface(PMIID interfaceID) const; \
 void AddRef() const; \
 void Release() const; \
 void PreDirty(ImplementationID prop = kInvalidImpl, bool16 allowModification = kTrue); \
 void PreDirtyNoMessage(ImplementationID prop = kInvalidImpl, bool16 allowModification = kTrue); \
protected: \
 HelperInterface fHelperInterface;

#define DECLARE_VIEW_HELPER_METHODS() \
public: \
 /*fViewIFaceConsistencyChecker is used only to produce compiler errors \
 if people use the wrong helper method declaraton type \
 while using CREATE_VIEW_PMINTERFACE*/ \
 void* fViewIFaceConsistencyChecker;\


#define DECLARE_PERSIST_DONTSNAPHOT_HELPER_METHODS() \
public: \
 /*fDontSnapshotIFaceConsistencyChecker is used only to produce compiler errors \
 if people use the wrong helper method declaraton type \
 while using CREATE_PERSIST_DONTSNAPSHOT_PMINTERFACE*/ \
 void* fDontSnapshotIFaceConsistencyChecker;\


#ifndef DEBUG
#define DEFINE_BASIC_HELPER_METHODS(cn) \
 IPMUnknown * cn::QueryInterface( PMIID interfaceID) const \
 {return fHelperInterface.QueryInterface(interfaceID); } \
 void cn::AddRef() const \
 { fHelperInterface.AddRef(); } \
 void cn::Release() const\
 { fHelperInterface.Release(); }
#else
#define DEFINE_BASIC_HELPER_METHODS(cn) \
 IPMUnknown * cn::QueryInterface( PMIID interfaceID) const \
 { \
 if (interfaceID == IID_IGETINTERFACEIMPL) \
 {return const_cast<cn*>(this);} \
 return fHelperInterface.QueryInterface(interfaceID); \
 } \
 void cn::AddRef() const \
 { fHelperInterface.AddRef(); } \
 void cn::Release() const \
 { fHelperInterface.Release(); }
#endif

#define DEFINE_HELPER_METHODS(cn) \
DEFINE_BASIC_HELPER_METHODS(cn)\
void cn::PreDirty(ImplementationID prop, bool16 allowModification) \
 { ::PreDirty(fHelperInterface.GetBoss(), this, prop, allowModification); } \
void cn::PreDirtyNoMessage(ImplementationID prop, bool16 allowModification) \
 { ::PreDirtyNoMessage(fHelperInterface.GetBoss(), this, prop, allowModification); } 

#define DEFINE_VIEW_HELPER_METHODS(cn) \
DEFINE_BASIC_HELPER_METHODS(cn)\
void cn::PreDirty(ImplementationID prop, bool16 allowModification) \
 {\
 InterfacePtr<IViewObjectChanges>viewObjectChanges (this, UseDefaultIID());\
 if (viewObjectChanges)\
 viewObjectChanges->SetDirty(fHelperInterface.GetBoss(), this, prop, allowModification);\
 } \
void cn::PreDirtyNoMessage(ImplementationID prop, bool16 allowModification) \
 { ASSERT_FAIL("Not appropriate for ViewInterfaces"); }

#define DEFINE_PERSIST_DONTSNAPHOT_HELPER_METHODS(cn) \
DEFINE_BASIC_HELPER_METHODS(cn)\
void cn::PreDirty(ImplementationID prop, bool16 allowModification) \
 {\
 IDataBase* db = ::GetDataBase(fHelperInterface.GetBoss());\
 DBChangesMonitorDisabler disabler(db);\
 ::PreDirty(fHelperInterface.GetBoss(), this, prop, allowModification); \
 } \
void cn::PreDirtyNoMessage(ImplementationID prop, bool16 allowModification) \
 {\
 IDataBase* db = ::GetDataBase(fHelperInterface.GetBoss());\
 DBChangesMonitorDisabler disabler(db);\
 ::PreDirtyNoMessage(fHelperInterface.GetBoss(), this, prop, allowModification);\
 } 

#define HELPER_METHODS_INIT(boss) fHelperInterface(boss)

#define DONTSNAPSHOT_HELPER_METHODS_INIT(boss) HELPER_METHODS_INIT(boss), fDontSnapshotIFaceConsistencyChecker(nil)

#endif // __HelperInterface__