mirror of
https://github.com/mozilla/gecko-dev.git
synced 2024-11-01 14:45:29 +00:00
489 lines
12 KiB
C++
489 lines
12 KiB
C++
/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
|
|
/* This Source Code Form is subject to the terms of the Mozilla Public
|
|
* License, v. 2.0. If a copy of the MPL was not distributed with this
|
|
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
|
|
|
|
#ifndef nsHtml5RefPtr_h
|
|
#define nsHtml5RefPtr_h
|
|
|
|
#include "nsThreadUtils.h"
|
|
|
|
template <class T>
|
|
class nsHtml5RefPtrReleaser : public nsRunnable
|
|
{
|
|
private:
|
|
T* mPtr;
|
|
public:
|
|
nsHtml5RefPtrReleaser(T* aPtr)
|
|
: mPtr(aPtr)
|
|
{}
|
|
NS_IMETHODIMP Run()
|
|
{
|
|
mPtr->Release();
|
|
return NS_OK;
|
|
}
|
|
};
|
|
|
|
// template <class T> class nsHtml5RefPtrGetterAddRefs;
|
|
|
|
/**
|
|
* Like nsRefPtr except release is proxied to the main thread. Mostly copied
|
|
* from nsRefPtr.
|
|
*/
|
|
template <class T>
|
|
class nsHtml5RefPtr
|
|
{
|
|
private:
|
|
|
|
void
|
|
assign_with_AddRef( T* rawPtr )
|
|
{
|
|
if ( rawPtr )
|
|
rawPtr->AddRef();
|
|
assign_assuming_AddRef(rawPtr);
|
|
}
|
|
|
|
void**
|
|
begin_assignment()
|
|
{
|
|
assign_assuming_AddRef(0);
|
|
return reinterpret_cast<void**>(&mRawPtr);
|
|
}
|
|
|
|
void
|
|
assign_assuming_AddRef( T* newPtr )
|
|
{
|
|
T* oldPtr = mRawPtr;
|
|
mRawPtr = newPtr;
|
|
if ( oldPtr )
|
|
release(oldPtr);
|
|
}
|
|
|
|
void
|
|
release( T* aPtr )
|
|
{
|
|
nsCOMPtr<nsIRunnable> releaser = new nsHtml5RefPtrReleaser<T>(aPtr);
|
|
if (NS_FAILED(NS_DispatchToMainThread(releaser)))
|
|
{
|
|
NS_WARNING("Failed to dispatch releaser event.");
|
|
}
|
|
}
|
|
|
|
private:
|
|
T* mRawPtr;
|
|
|
|
public:
|
|
typedef T element_type;
|
|
|
|
~nsHtml5RefPtr()
|
|
{
|
|
if ( mRawPtr )
|
|
release(mRawPtr);
|
|
}
|
|
|
|
// Constructors
|
|
|
|
nsHtml5RefPtr()
|
|
: mRawPtr(0)
|
|
// default constructor
|
|
{
|
|
}
|
|
|
|
nsHtml5RefPtr( const nsHtml5RefPtr<T>& aSmartPtr )
|
|
: mRawPtr(aSmartPtr.mRawPtr)
|
|
// copy-constructor
|
|
{
|
|
if ( mRawPtr )
|
|
mRawPtr->AddRef();
|
|
}
|
|
|
|
nsHtml5RefPtr( T* aRawPtr )
|
|
: mRawPtr(aRawPtr)
|
|
// construct from a raw pointer (of the right type)
|
|
{
|
|
if ( mRawPtr )
|
|
mRawPtr->AddRef();
|
|
}
|
|
|
|
nsHtml5RefPtr( const already_AddRefed<T>& aSmartPtr )
|
|
: mRawPtr(aSmartPtr.mRawPtr)
|
|
// construct from |dont_AddRef(expr)|
|
|
{
|
|
}
|
|
|
|
// Assignment operators
|
|
|
|
nsHtml5RefPtr<T>&
|
|
operator=( const nsHtml5RefPtr<T>& rhs )
|
|
// copy assignment operator
|
|
{
|
|
assign_with_AddRef(rhs.mRawPtr);
|
|
return *this;
|
|
}
|
|
|
|
nsHtml5RefPtr<T>&
|
|
operator=( T* rhs )
|
|
// assign from a raw pointer (of the right type)
|
|
{
|
|
assign_with_AddRef(rhs);
|
|
return *this;
|
|
}
|
|
|
|
nsHtml5RefPtr<T>&
|
|
operator=( const already_AddRefed<T>& rhs )
|
|
// assign from |dont_AddRef(expr)|
|
|
{
|
|
assign_assuming_AddRef(rhs.mRawPtr);
|
|
return *this;
|
|
}
|
|
|
|
// Other pointer operators
|
|
|
|
void
|
|
swap( nsHtml5RefPtr<T>& rhs )
|
|
// ...exchange ownership with |rhs|; can save a pair of refcount operations
|
|
{
|
|
T* temp = rhs.mRawPtr;
|
|
rhs.mRawPtr = mRawPtr;
|
|
mRawPtr = temp;
|
|
}
|
|
|
|
void
|
|
swap( T*& rhs )
|
|
// ...exchange ownership with |rhs|; can save a pair of refcount operations
|
|
{
|
|
T* temp = rhs;
|
|
rhs = mRawPtr;
|
|
mRawPtr = temp;
|
|
}
|
|
|
|
already_AddRefed<T>
|
|
forget()
|
|
// return the value of mRawPtr and null out mRawPtr. Useful for
|
|
// already_AddRefed return values.
|
|
{
|
|
T* temp = 0;
|
|
swap(temp);
|
|
return temp;
|
|
}
|
|
|
|
template <typename I>
|
|
void
|
|
forget( I** rhs)
|
|
// Set the target of rhs to the value of mRawPtr and null out mRawPtr.
|
|
// Useful to avoid unnecessary AddRef/Release pairs with "out"
|
|
// parameters where rhs bay be a T** or an I** where I is a base class
|
|
// of T.
|
|
{
|
|
NS_ASSERTION(rhs, "Null pointer passed to forget!");
|
|
*rhs = mRawPtr;
|
|
mRawPtr = 0;
|
|
}
|
|
|
|
T*
|
|
get() const
|
|
/*
|
|
Prefer the implicit conversion provided automatically by |operator T*() const|.
|
|
Use |get()| to resolve ambiguity or to get a castable pointer.
|
|
*/
|
|
{
|
|
return const_cast<T*>(mRawPtr);
|
|
}
|
|
|
|
operator T*() const
|
|
/*
|
|
...makes an |nsHtml5RefPtr| act like its underlying raw pointer type whenever it
|
|
is used in a context where a raw pointer is expected. It is this operator
|
|
that makes an |nsHtml5RefPtr| substitutable for a raw pointer.
|
|
|
|
Prefer the implicit use of this operator to calling |get()|, except where
|
|
necessary to resolve ambiguity.
|
|
*/
|
|
{
|
|
return get();
|
|
}
|
|
|
|
T*
|
|
operator->() const
|
|
{
|
|
NS_PRECONDITION(mRawPtr != 0, "You can't dereference a NULL nsHtml5RefPtr with operator->().");
|
|
return get();
|
|
}
|
|
|
|
nsHtml5RefPtr<T>*
|
|
get_address()
|
|
// This is not intended to be used by clients. See |address_of|
|
|
// below.
|
|
{
|
|
return this;
|
|
}
|
|
|
|
const nsHtml5RefPtr<T>*
|
|
get_address() const
|
|
// This is not intended to be used by clients. See |address_of|
|
|
// below.
|
|
{
|
|
return this;
|
|
}
|
|
|
|
public:
|
|
T&
|
|
operator*() const
|
|
{
|
|
NS_PRECONDITION(mRawPtr != 0, "You can't dereference a NULL nsHtml5RefPtr with operator*().");
|
|
return *get();
|
|
}
|
|
|
|
T**
|
|
StartAssignment()
|
|
{
|
|
#ifndef NSCAP_FEATURE_INLINE_STARTASSIGNMENT
|
|
return reinterpret_cast<T**>(begin_assignment());
|
|
#else
|
|
assign_assuming_AddRef(0);
|
|
return reinterpret_cast<T**>(&mRawPtr);
|
|
#endif
|
|
}
|
|
};
|
|
|
|
template <class T>
|
|
inline
|
|
nsHtml5RefPtr<T>*
|
|
address_of( nsHtml5RefPtr<T>& aPtr )
|
|
{
|
|
return aPtr.get_address();
|
|
}
|
|
|
|
template <class T>
|
|
inline
|
|
const nsHtml5RefPtr<T>*
|
|
address_of( const nsHtml5RefPtr<T>& aPtr )
|
|
{
|
|
return aPtr.get_address();
|
|
}
|
|
|
|
template <class T>
|
|
class nsHtml5RefPtrGetterAddRefs
|
|
/*
|
|
...
|
|
|
|
This class is designed to be used for anonymous temporary objects in the
|
|
argument list of calls that return COM interface pointers, e.g.,
|
|
|
|
nsHtml5RefPtr<IFoo> fooP;
|
|
...->GetAddRefedPointer(getter_AddRefs(fooP))
|
|
|
|
DO NOT USE THIS TYPE DIRECTLY IN YOUR CODE. Use |getter_AddRefs()| instead.
|
|
|
|
When initialized with a |nsHtml5RefPtr|, as in the example above, it returns
|
|
a |void**|, a |T**|, or an |nsISupports**| as needed, that the
|
|
outer call (|GetAddRefedPointer| in this case) can fill in.
|
|
|
|
This type should be a nested class inside |nsHtml5RefPtr<T>|.
|
|
*/
|
|
{
|
|
public:
|
|
explicit
|
|
nsHtml5RefPtrGetterAddRefs( nsHtml5RefPtr<T>& aSmartPtr )
|
|
: mTargetSmartPtr(aSmartPtr)
|
|
{
|
|
// nothing else to do
|
|
}
|
|
|
|
operator void**()
|
|
{
|
|
return reinterpret_cast<void**>(mTargetSmartPtr.StartAssignment());
|
|
}
|
|
|
|
operator T**()
|
|
{
|
|
return mTargetSmartPtr.StartAssignment();
|
|
}
|
|
|
|
T*&
|
|
operator*()
|
|
{
|
|
return *(mTargetSmartPtr.StartAssignment());
|
|
}
|
|
|
|
private:
|
|
nsHtml5RefPtr<T>& mTargetSmartPtr;
|
|
};
|
|
|
|
template <class T>
|
|
inline
|
|
nsHtml5RefPtrGetterAddRefs<T>
|
|
getter_AddRefs( nsHtml5RefPtr<T>& aSmartPtr )
|
|
/*
|
|
Used around a |nsHtml5RefPtr| when
|
|
...makes the class |nsHtml5RefPtrGetterAddRefs<T>| invisible.
|
|
*/
|
|
{
|
|
return nsHtml5RefPtrGetterAddRefs<T>(aSmartPtr);
|
|
}
|
|
|
|
|
|
|
|
// Comparing two |nsHtml5RefPtr|s
|
|
|
|
template <class T, class U>
|
|
inline
|
|
bool
|
|
operator==( const nsHtml5RefPtr<T>& lhs, const nsHtml5RefPtr<U>& rhs )
|
|
{
|
|
return static_cast<const T*>(lhs.get()) == static_cast<const U*>(rhs.get());
|
|
}
|
|
|
|
|
|
template <class T, class U>
|
|
inline
|
|
bool
|
|
operator!=( const nsHtml5RefPtr<T>& lhs, const nsHtml5RefPtr<U>& rhs )
|
|
{
|
|
return static_cast<const T*>(lhs.get()) != static_cast<const U*>(rhs.get());
|
|
}
|
|
|
|
|
|
// Comparing an |nsHtml5RefPtr| to a raw pointer
|
|
|
|
template <class T, class U>
|
|
inline
|
|
bool
|
|
operator==( const nsHtml5RefPtr<T>& lhs, const U* rhs )
|
|
{
|
|
return static_cast<const T*>(lhs.get()) == static_cast<const U*>(rhs);
|
|
}
|
|
|
|
template <class T, class U>
|
|
inline
|
|
bool
|
|
operator==( const U* lhs, const nsHtml5RefPtr<T>& rhs )
|
|
{
|
|
return static_cast<const U*>(lhs) == static_cast<const T*>(rhs.get());
|
|
}
|
|
|
|
template <class T, class U>
|
|
inline
|
|
bool
|
|
operator!=( const nsHtml5RefPtr<T>& lhs, const U* rhs )
|
|
{
|
|
return static_cast<const T*>(lhs.get()) != static_cast<const U*>(rhs);
|
|
}
|
|
|
|
template <class T, class U>
|
|
inline
|
|
bool
|
|
operator!=( const U* lhs, const nsHtml5RefPtr<T>& rhs )
|
|
{
|
|
return static_cast<const U*>(lhs) != static_cast<const T*>(rhs.get());
|
|
}
|
|
|
|
// To avoid ambiguities caused by the presence of builtin |operator==|s
|
|
// creating a situation where one of the |operator==| defined above
|
|
// has a better conversion for one argument and the builtin has a
|
|
// better conversion for the other argument, define additional
|
|
// |operator==| without the |const| on the raw pointer.
|
|
// See bug 65664 for details.
|
|
|
|
#ifndef NSCAP_DONT_PROVIDE_NONCONST_OPEQ
|
|
template <class T, class U>
|
|
inline
|
|
bool
|
|
operator==( const nsHtml5RefPtr<T>& lhs, U* rhs )
|
|
{
|
|
return static_cast<const T*>(lhs.get()) == const_cast<const U*>(rhs);
|
|
}
|
|
|
|
template <class T, class U>
|
|
inline
|
|
bool
|
|
operator==( U* lhs, const nsHtml5RefPtr<T>& rhs )
|
|
{
|
|
return const_cast<const U*>(lhs) == static_cast<const T*>(rhs.get());
|
|
}
|
|
|
|
template <class T, class U>
|
|
inline
|
|
bool
|
|
operator!=( const nsHtml5RefPtr<T>& lhs, U* rhs )
|
|
{
|
|
return static_cast<const T*>(lhs.get()) != const_cast<const U*>(rhs);
|
|
}
|
|
|
|
template <class T, class U>
|
|
inline
|
|
bool
|
|
operator!=( U* lhs, const nsHtml5RefPtr<T>& rhs )
|
|
{
|
|
return const_cast<const U*>(lhs) != static_cast<const T*>(rhs.get());
|
|
}
|
|
#endif
|
|
|
|
|
|
|
|
// Comparing an |nsHtml5RefPtr| to |0|
|
|
|
|
template <class T>
|
|
inline
|
|
bool
|
|
operator==( const nsHtml5RefPtr<T>& lhs, NSCAP_Zero* rhs )
|
|
// specifically to allow |smartPtr == 0|
|
|
{
|
|
return static_cast<const void*>(lhs.get()) == reinterpret_cast<const void*>(rhs);
|
|
}
|
|
|
|
template <class T>
|
|
inline
|
|
bool
|
|
operator==( NSCAP_Zero* lhs, const nsHtml5RefPtr<T>& rhs )
|
|
// specifically to allow |0 == smartPtr|
|
|
{
|
|
return reinterpret_cast<const void*>(lhs) == static_cast<const void*>(rhs.get());
|
|
}
|
|
|
|
template <class T>
|
|
inline
|
|
bool
|
|
operator!=( const nsHtml5RefPtr<T>& lhs, NSCAP_Zero* rhs )
|
|
// specifically to allow |smartPtr != 0|
|
|
{
|
|
return static_cast<const void*>(lhs.get()) != reinterpret_cast<const void*>(rhs);
|
|
}
|
|
|
|
template <class T>
|
|
inline
|
|
bool
|
|
operator!=( NSCAP_Zero* lhs, const nsHtml5RefPtr<T>& rhs )
|
|
// specifically to allow |0 != smartPtr|
|
|
{
|
|
return reinterpret_cast<const void*>(lhs) != static_cast<const void*>(rhs.get());
|
|
}
|
|
|
|
|
|
#ifdef HAVE_CPP_TROUBLE_COMPARING_TO_ZERO
|
|
|
|
// We need to explicitly define comparison operators for `int'
|
|
// because the compiler is lame.
|
|
|
|
template <class T>
|
|
inline
|
|
bool
|
|
operator==( const nsHtml5RefPtr<T>& lhs, int rhs )
|
|
// specifically to allow |smartPtr == 0|
|
|
{
|
|
return static_cast<const void*>(lhs.get()) == reinterpret_cast<const void*>(rhs);
|
|
}
|
|
|
|
template <class T>
|
|
inline
|
|
bool
|
|
operator==( int lhs, const nsHtml5RefPtr<T>& rhs )
|
|
// specifically to allow |0 == smartPtr|
|
|
{
|
|
return reinterpret_cast<const void*>(lhs) == static_cast<const void*>(rhs.get());
|
|
}
|
|
|
|
#endif // !defined(HAVE_CPP_TROUBLE_COMPARING_TO_ZERO)
|
|
|
|
#endif // !defined(nsHtml5RefPtr_h)
|