gecko-dev/xpcom/base/nsAgg.h

215 lines
14 KiB
C++

/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/* ***** BEGIN LICENSE BLOCK *****
* Version: MPL 1.1/GPL 2.0/LGPL 2.1
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* The Original Code is mozilla.org code.
*
* The Initial Developer of the Original Code is
* Netscape Communications Corporation.
* Portions created by the Initial Developer are Copyright (C) 1998
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
*
* Alternatively, the contents of this file may be used under the terms of
* either of the GNU General Public License Version 2 or later (the "GPL"),
* or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
* in which case the provisions of the GPL or the LGPL are applicable instead
* of those above. If you wish to allow use of your version of this file only
* under the terms of either the GPL or the LGPL, and not to allow others to
* use your version of this file under the terms of the MPL, indicate your
* decision by deleting the provisions above and replace them with the notice
* and other provisions required by the GPL or the LGPL. If you do not delete
* the provisions above, a recipient may use your version of this file under
* the terms of any one of the MPL, the GPL or the LGPL.
*
* ***** END LICENSE BLOCK ***** */
#ifndef nsAgg_h___
#define nsAgg_h___
#include "nsISupports.h"
////////////////////////////////////////////////////////////////////////////////
// Put this in your class's declaration:
#define NS_DECL_AGGREGATED \
NS_DECL_ISUPPORTS \
\
public: \
\
/** \
* Returns the nsISupports pointer of the inner object (aka the \
* aggregatee). This pointer is really only useful to the outer object \
* (aka the aggregator), which can use it to hold on to the inner \
* object. Anything else wants the nsISupports pointer of the outer \
* object (gotten by QI'ing inner or outer to nsISupports). This method \
* returns a non-addrefed pointer. \
* @return the nsISupports pointer of the inner object \
*/ \
nsISupports* InnerObject(void) { return &fAggregated; } \
\
private: \
\
/* You must implement this operation instead of the nsISupports */ \
/* methods. */ \
nsresult \
AggregatedQueryInterface(const nsIID& aIID, void** aInstancePtr); \
\
class Internal : public nsISupports { \
public: \
\
Internal() {} \
\
NS_IMETHOD QueryInterface(const nsIID& aIID, void** aInstancePtr); \
NS_IMETHOD_(nsrefcnt) AddRef(void); \
NS_IMETHOD_(nsrefcnt) Release(void); \
\
}; \
\
friend class Internal; \
\
nsISupports* fOuter; \
Internal fAggregated; \
\
public: \
// Put this in your class's constructor:
#define NS_INIT_AGGREGATED(outer) \
PR_BEGIN_MACRO \
fOuter = outer ? outer : &fAggregated; \
PR_END_MACRO
// Put this in your class's implementation file:
#define NS_IMPL_AGGREGATED(_class) \
NS_IMETHODIMP \
_class::QueryInterface(const nsIID& aIID, void** aInstancePtr) \
{ \
return fOuter->QueryInterface(aIID, aInstancePtr); \
} \
\
NS_IMETHODIMP_(nsrefcnt) \
_class::AddRef(void) \
{ \
return fOuter->AddRef(); \
} \
\
NS_IMETHODIMP_(nsrefcnt) \
_class::Release(void) \
{ \
return fOuter->Release(); \
} \
\
NS_IMETHODIMP \
_class::Internal::QueryInterface(const nsIID& aIID, void** aInstancePtr) \
{ \
_class* agg = (_class*)((char*)(this) - offsetof(_class, fAggregated)); \
return agg->AggregatedQueryInterface(aIID, aInstancePtr); \
} \
\
NS_IMETHODIMP_(nsrefcnt) \
_class::Internal::AddRef(void) \
{ \
_class* agg = (_class*)((char*)(this) - offsetof(_class, fAggregated)); \
NS_PRECONDITION(PRInt32(agg->mRefCnt) >= 0, "illegal refcnt"); \
++agg->mRefCnt; \
NS_LOG_ADDREF(this, agg->mRefCnt, #_class, sizeof(*this)); \
return agg->mRefCnt; \
} \
\
NS_IMETHODIMP_(nsrefcnt) \
_class::Internal::Release(void) \
{ \
_class* agg = (_class*)((char*)(this) - offsetof(_class, fAggregated)); \
NS_PRECONDITION(0 != agg->mRefCnt, "dup release"); \
--agg->mRefCnt; \
NS_LOG_RELEASE(this, agg->mRefCnt, #_class); \
if (agg->mRefCnt == 0) { \
agg->mRefCnt = 1; /* stabilize */ \
NS_DELETEXPCOM(agg); \
return 0; \
} \
return agg->mRefCnt; \
} \
// for use with QI macros in nsISupportsUtils.h:
#define NS_INTERFACE_MAP_BEGIN_AGGREGATED(_class) \
NS_IMPL_AGGREGATED_QUERY_HEAD(_class)
#define NS_IMPL_AGGREGATED_QUERY_HEAD(_class) \
nsresult \
_class::AggregatedQueryInterface(REFNSIID aIID, void** aInstancePtr) \
{ \
NS_ASSERTION(aInstancePtr, \
"AggregatedQueryInterface requires a non-NULL result ptr!"); \
if ( !aInstancePtr ) \
return NS_ERROR_NULL_POINTER; \
nsISupports* foundInterface; \
if ( aIID.Equals(NS_GET_IID(nsISupports)) ) \
foundInterface = InnerObject(); \
else
#define NS_GENERIC_AGGREGATED_CONSTRUCTOR(_InstanceClass) \
static NS_METHOD \
_InstanceClass##Constructor(nsISupports *aOuter, REFNSIID aIID, \
void **aResult) \
{ \
*aResult = nsnull; \
\
NS_ENSURE_PROPER_AGGREGATION(aOuter, aIID); \
\
_InstanceClass* inst = new _InstanceClass(aOuter); \
if (!inst) { \
return NS_ERROR_OUT_OF_MEMORY; \
} \
\
nsISupports* inner = inst->InnerObject(); \
nsresult rv = inner->QueryInterface(aIID, aResult); \
if (NS_FAILED(rv)) { \
delete inst; \
} \
\
return rv; \
} \
#define NS_GENERIC_AGGREGATED_CONSTRUCTOR_INIT(_InstanceClass, _InitMethod) \
static NS_METHOD \
_InstanceClass##Constructor(nsISupports *aOuter, REFNSIID aIID, \
void **aResult) \
{ \
*aResult = nsnull; \
\
NS_ENSURE_PROPER_AGGREGATION(aOuter, aIID); \
\
_InstanceClass* inst = new _InstanceClass(aOuter); \
if (!inst) { \
return NS_ERROR_OUT_OF_MEMORY; \
} \
\
nsISupports* inner = inst->InnerObject(); \
NS_ADDREF(inner); \
nsresult rv = inst->_InitMethod(); \
if (NS_SUCCEEDED(rv)) { \
rv = inner->QueryInterface(aIID, aResult); \
} \
NS_RELEASE(inner); \
\
return rv; \
} \
#endif /* nsAgg_h___ */