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/*
* Copyright (C) 2007, 2010 Apple Inc. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
* OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef COMPtr_h
#define COMPtr_h
#include <unknwn.h>
#include <wtf/Assertions.h>
#include <wtf/HashTraits.h>
#ifdef __midl
typedef LONG HRESULT;
#else
typedef _Return_type_success_(return >= 0) long HRESULT;
#endif // __midl
// FIXME: Should we put this into the WebCore namespace and use "using" on it
// as we do with things in WTF?
enum AdoptCOMTag { AdoptCOM };
enum QueryTag { Query };
enum CreateTag { Create };
template<typename T> class COMPtr {
public:
typedef T* PtrType;
COMPtr() : m_ptr(nullptr) { }
COMPtr(T* ptr) : m_ptr(ptr) { if (m_ptr) m_ptr->AddRef(); }
COMPtr(AdoptCOMTag, T* ptr) : m_ptr(ptr) { }
COMPtr(const COMPtr& o) : m_ptr(o.m_ptr) { if (T* ptr = m_ptr) ptr->AddRef(); }
COMPtr(COMPtr&& o) : m_ptr(o.leakRef()) { }
COMPtr(QueryTag, IUnknown* ptr) : m_ptr(copyQueryInterfaceRef(ptr)) { }
template<typename U> COMPtr(QueryTag, const COMPtr<U>& ptr) : m_ptr(copyQueryInterfaceRef(ptr.get())) { }
COMPtr(CreateTag, const IID& clsid) : m_ptr(createInstance(clsid)) { }
// Hash table deleted values, which are only constructed and never copied or destroyed.
COMPtr(WTF::HashTableDeletedValueType) : m_ptr(hashTableDeletedValue()) { }
bool isHashTableDeletedValue() const { return m_ptr == hashTableDeletedValue(); }
~COMPtr() { if (m_ptr) m_ptr->Release(); }
T* get() const { return m_ptr; }
void clear();
T* leakRef();
T& operator*() const { return *m_ptr; }
T* operator->() const { return m_ptr; }
T** operator&() { ASSERT(!m_ptr); return &m_ptr; }
bool operator!() const { return !m_ptr; }
// This conversion operator allows implicit conversion to bool but not to other integer types.
typedef T* (COMPtr::*UnspecifiedBoolType)() const;
operator UnspecifiedBoolType() const { return m_ptr ? &COMPtr::get : 0; }
COMPtr& operator=(const COMPtr&);
COMPtr& operator=(COMPtr&&);
COMPtr& operator=(T*);
template<typename U> COMPtr& operator=(const COMPtr<U>&);
void query(IUnknown* ptr) { adoptRef(copyQueryInterfaceRef(ptr)); }
template<typename U> void query(const COMPtr<U>& ptr) { query(ptr.get()); }
void create(const IID& clsid) { adoptRef(createInstance(clsid)); }
template<typename U> HRESULT copyRefTo(U**);
void adoptRef(T*);
private:
static T* copyQueryInterfaceRef(IUnknown*);
static T* createInstance(const IID& clsid);
static T* hashTableDeletedValue() { return reinterpret_cast<T*>(-1); }
T* m_ptr;
};
template<typename T> inline COMPtr<T> adoptCOM(T *ptr)
{
return COMPtr<T>(AdoptCOM, ptr);
}
template<typename T> inline void COMPtr<T>::clear()
{
if (T* ptr = m_ptr) {
m_ptr = 0;
ptr->Release();
}
}
template<typename T> inline T* COMPtr<T>::leakRef()
{
T* ptr = m_ptr;
m_ptr = 0;
return ptr;
}
template<typename T> inline T* COMPtr<T>::createInstance(const IID& clsid)
{
T* result;
if (FAILED(CoCreateInstance(clsid, 0, CLSCTX_ALL, __uuidof(result), reinterpret_cast<void**>(&result))))
return 0;
return result;
}
template<typename T> inline T* COMPtr<T>::copyQueryInterfaceRef(IUnknown* ptr)
{
if (!ptr)
return 0;
T* result;
if (FAILED(ptr->QueryInterface(&result)))
return 0;
return result;
}
template<typename T> template<typename U> inline HRESULT COMPtr<T>::copyRefTo(U** ptr)
{
if (!ptr)
return E_POINTER;
*ptr = m_ptr;
if (m_ptr)
m_ptr->AddRef();
return S_OK;
}
template<typename T> inline void COMPtr<T>::adoptRef(T *ptr)
{
if (m_ptr)
m_ptr->Release();
m_ptr = ptr;
}
template<typename T> inline COMPtr<T>& COMPtr<T>::operator=(const COMPtr<T>& o)
{
T* optr = o.get();
if (optr)
optr->AddRef();
T* ptr = m_ptr;
m_ptr = optr;
if (ptr)
ptr->Release();
return *this;
}
template<typename T> inline COMPtr<T>& COMPtr<T>::operator=(COMPtr<T>&& o)
{
if (T* ptr = m_ptr)
ptr->Release();
m_ptr = o.leakRef();
return *this;
}
template<typename T> template<typename U> inline COMPtr<T>& COMPtr<T>::operator=(const COMPtr<U>& o)
{
T* optr = o.get();
if (optr)
optr->AddRef();
T* ptr = m_ptr;
m_ptr = optr;
if (ptr)
ptr->Release();
return *this;
}
template<typename T> inline COMPtr<T>& COMPtr<T>::operator=(T* optr)
{
if (optr)
optr->AddRef();
T* ptr = m_ptr;
m_ptr = optr;
if (ptr)
ptr->Release();
return *this;
}
template<typename T, typename U> inline bool operator==(const COMPtr<T>& a, const COMPtr<U>& b)
{
return a.get() == b.get();
}
template<typename T, typename U> inline bool operator==(const COMPtr<T>& a, U* b)
{
return a.get() == b;
}
template<typename T, typename U> inline bool operator==(T* a, const COMPtr<U>& b)
{
return a == b.get();
}
template<typename T, typename U> inline bool operator!=(const COMPtr<T>& a, const COMPtr<U>& b)
{
return a.get() != b.get();
}
template<typename T, typename U> inline bool operator!=(const COMPtr<T>& a, U* b)
{
return a.get() != b;
}
template<typename T, typename U> inline bool operator!=(T* a, const COMPtr<U>& b)
{
return a != b.get();
}
#if ASSERT_ENABLED
inline unsigned refCount(IUnknown* ptr)
{
if (!ptr)
return 0;
unsigned temp = ptr->AddRef();
unsigned value = ptr->Release();
ASSERT(temp = value + 1);
return value;
}
#endif
namespace WTF {
template<typename P> struct IsSmartPtr<COMPtr<P>> {
static const bool value = true;
};
template<typename P> struct HashTraits<COMPtr<P> > : SimpleClassHashTraits<COMPtr<P>> {
static P* emptyValue() { return nullptr; }
typedef P* PeekType;
static PeekType peek(const COMPtr<P>& value) { return value.get(); }
static PeekType peek(P* value) { return value; }
};
template<typename P> struct DefaultHash<COMPtr<P>> {
typedef PtrHash<COMPtr<P>> Hash;
};
}
#endif