cef/include/base/cef_callback_list.h

445 lines
14 KiB
C++

// Copyright (c) 2014 Marshall A. Greenblatt. Portions copyright (c) 2013
// Google 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:
//
// * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
// * 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.
// * Neither the name of Google Inc. nor the name Chromium Embedded
// Framework nor the names of its contributors may be used to endorse
// or promote products derived from this software without specific prior
// written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "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 THE COPYRIGHT
// OWNER 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 CEF_INCLUDE_BASE_CEF_CALLBACK_LIST_H_
#define CEF_INCLUDE_BASE_CEF_CALLBACK_LIST_H_
#pragma once
#if defined(BASE_CALLBACK_LIST_H_)
// Do nothing if the Chromium header has already been included.
// This can happen in cases where Chromium code is used directly by the
// client application. When using Chromium code directly always include
// the Chromium header first to avoid type conflicts.
#elif defined(BUILDING_CEF_SHARED)
// When building CEF include the Chromium header directly.
#include "base/callback_list.h"
#else // !BUILDING_CEF_SHARED
// The following is substantially similar to the Chromium implementation.
// If the Chromium implementation diverges the below implementation should be
// updated to match.
#include <list>
#include "include/base/cef_basictypes.h"
#include "include/base/cef_callback.h"
#include "include/base/internal/cef_callback_internal.h"
#include "include/base/cef_build.h"
#include "include/base/cef_logging.h"
#include "include/base/cef_macros.h"
#include "include/base/cef_scoped_ptr.h"
// OVERVIEW:
//
// A container for a list of callbacks. Unlike a normal STL vector or list,
// this container can be modified during iteration without invalidating the
// iterator. It safely handles the case of a callback removing itself
// or another callback from the list while callbacks are being run.
//
// TYPICAL USAGE:
//
// class MyWidget {
// public:
// ...
//
// typedef base::Callback<void(const Foo&)> OnFooCallback;
//
// scoped_ptr<base::CallbackList<void(const Foo&)>::Subscription>
// RegisterCallback(const OnFooCallback& cb) {
// return callback_list_.Add(cb);
// }
//
// private:
// void NotifyFoo(const Foo& foo) {
// callback_list_.Notify(foo);
// }
//
// base::CallbackList<void(const Foo&)> callback_list_;
//
// DISALLOW_COPY_AND_ASSIGN(MyWidget);
// };
//
//
// class MyWidgetListener {
// public:
// MyWidgetListener::MyWidgetListener() {
// foo_subscription_ = MyWidget::GetCurrent()->RegisterCallback(
// base::Bind(&MyWidgetListener::OnFoo, this)));
// }
//
// MyWidgetListener::~MyWidgetListener() {
// // Subscription gets deleted automatically and will deregister
// // the callback in the process.
// }
//
// private:
// void OnFoo(const Foo& foo) {
// // Do something.
// }
//
// scoped_ptr<base::CallbackList<void(const Foo&)>::Subscription>
// foo_subscription_;
//
// DISALLOW_COPY_AND_ASSIGN(MyWidgetListener);
// };
namespace base {
namespace internal {
template <typename CallbackType>
class CallbackListBase {
public:
class Subscription {
public:
Subscription(CallbackListBase<CallbackType>* list,
typename std::list<CallbackType>::iterator iter)
: list_(list),
iter_(iter) {
}
~Subscription() {
if (list_->active_iterator_count_) {
iter_->Reset();
} else {
list_->callbacks_.erase(iter_);
if (!list_->removal_callback_.is_null())
list_->removal_callback_.Run();
}
}
private:
CallbackListBase<CallbackType>* list_;
typename std::list<CallbackType>::iterator iter_;
DISALLOW_COPY_AND_ASSIGN(Subscription);
};
// Add a callback to the list. The callback will remain registered until the
// returned Subscription is destroyed, which must occur before the
// CallbackList is destroyed.
scoped_ptr<Subscription> Add(const CallbackType& cb) WARN_UNUSED_RESULT {
DCHECK(!cb.is_null());
return scoped_ptr<Subscription>(
new Subscription(this, callbacks_.insert(callbacks_.end(), cb)));
}
// Sets a callback which will be run when a subscription list is changed.
void set_removal_callback(const Closure& callback) {
removal_callback_ = callback;
}
// Returns true if there are no subscriptions. This is only valid to call when
// not looping through the list.
bool empty() {
DCHECK_EQ(0, active_iterator_count_);
return callbacks_.empty();
}
protected:
// An iterator class that can be used to access the list of callbacks.
class Iterator {
public:
explicit Iterator(CallbackListBase<CallbackType>* list)
: list_(list),
list_iter_(list_->callbacks_.begin()) {
++list_->active_iterator_count_;
}
Iterator(const Iterator& iter)
: list_(iter.list_),
list_iter_(iter.list_iter_) {
++list_->active_iterator_count_;
}
~Iterator() {
if (list_ && --list_->active_iterator_count_ == 0) {
list_->Compact();
}
}
CallbackType* GetNext() {
while ((list_iter_ != list_->callbacks_.end()) && list_iter_->is_null())
++list_iter_;
CallbackType* cb = NULL;
if (list_iter_ != list_->callbacks_.end()) {
cb = &(*list_iter_);
++list_iter_;
}
return cb;
}
private:
CallbackListBase<CallbackType>* list_;
typename std::list<CallbackType>::iterator list_iter_;
};
CallbackListBase() : active_iterator_count_(0) {}
~CallbackListBase() {
DCHECK_EQ(0, active_iterator_count_);
DCHECK_EQ(0U, callbacks_.size());
}
// Returns an instance of a CallbackListBase::Iterator which can be used
// to run callbacks.
Iterator GetIterator() {
return Iterator(this);
}
// Compact the list: remove any entries which were NULLed out during
// iteration.
void Compact() {
typename std::list<CallbackType>::iterator it = callbacks_.begin();
bool updated = false;
while (it != callbacks_.end()) {
if ((*it).is_null()) {
updated = true;
it = callbacks_.erase(it);
} else {
++it;
}
if (updated && !removal_callback_.is_null())
removal_callback_.Run();
}
}
private:
std::list<CallbackType> callbacks_;
int active_iterator_count_;
Closure removal_callback_;
DISALLOW_COPY_AND_ASSIGN(CallbackListBase);
};
} // namespace internal
template <typename Sig> class CallbackList;
template <>
class CallbackList<void(void)>
: public internal::CallbackListBase<Callback<void(void)> > {
public:
typedef Callback<void(void)> CallbackType;
CallbackList() {}
void Notify() {
internal::CallbackListBase<CallbackType>::Iterator it =
this->GetIterator();
CallbackType* cb;
while ((cb = it.GetNext()) != NULL) {
cb->Run();
}
}
private:
DISALLOW_COPY_AND_ASSIGN(CallbackList);
};
template <typename A1>
class CallbackList<void(A1)>
: public internal::CallbackListBase<Callback<void(A1)> > {
public:
typedef Callback<void(A1)> CallbackType;
CallbackList() {}
void Notify(typename internal::CallbackParamTraits<A1>::ForwardType a1) {
typename internal::CallbackListBase<CallbackType>::Iterator it =
this->GetIterator();
CallbackType* cb;
while ((cb = it.GetNext()) != NULL) {
cb->Run(a1);
}
}
private:
DISALLOW_COPY_AND_ASSIGN(CallbackList);
};
template <typename A1, typename A2>
class CallbackList<void(A1, A2)>
: public internal::CallbackListBase<Callback<void(A1, A2)> > {
public:
typedef Callback<void(A1, A2)> CallbackType;
CallbackList() {}
void Notify(typename internal::CallbackParamTraits<A1>::ForwardType a1,
typename internal::CallbackParamTraits<A2>::ForwardType a2) {
typename internal::CallbackListBase<CallbackType>::Iterator it =
this->GetIterator();
CallbackType* cb;
while ((cb = it.GetNext()) != NULL) {
cb->Run(a1, a2);
}
}
private:
DISALLOW_COPY_AND_ASSIGN(CallbackList);
};
template <typename A1, typename A2, typename A3>
class CallbackList<void(A1, A2, A3)>
: public internal::CallbackListBase<Callback<void(A1, A2, A3)> > {
public:
typedef Callback<void(A1, A2, A3)> CallbackType;
CallbackList() {}
void Notify(typename internal::CallbackParamTraits<A1>::ForwardType a1,
typename internal::CallbackParamTraits<A2>::ForwardType a2,
typename internal::CallbackParamTraits<A3>::ForwardType a3) {
typename internal::CallbackListBase<CallbackType>::Iterator it =
this->GetIterator();
CallbackType* cb;
while ((cb = it.GetNext()) != NULL) {
cb->Run(a1, a2, a3);
}
}
private:
DISALLOW_COPY_AND_ASSIGN(CallbackList);
};
template <typename A1, typename A2, typename A3, typename A4>
class CallbackList<void(A1, A2, A3, A4)>
: public internal::CallbackListBase<Callback<void(A1, A2, A3, A4)> > {
public:
typedef Callback<void(A1, A2, A3, A4)> CallbackType;
CallbackList() {}
void Notify(typename internal::CallbackParamTraits<A1>::ForwardType a1,
typename internal::CallbackParamTraits<A2>::ForwardType a2,
typename internal::CallbackParamTraits<A3>::ForwardType a3,
typename internal::CallbackParamTraits<A4>::ForwardType a4) {
typename internal::CallbackListBase<CallbackType>::Iterator it =
this->GetIterator();
CallbackType* cb;
while ((cb = it.GetNext()) != NULL) {
cb->Run(a1, a2, a3, a4);
}
}
private:
DISALLOW_COPY_AND_ASSIGN(CallbackList);
};
template <typename A1, typename A2, typename A3, typename A4, typename A5>
class CallbackList<void(A1, A2, A3, A4, A5)>
: public internal::CallbackListBase<Callback<void(A1, A2, A3, A4, A5)> > {
public:
typedef Callback<void(A1, A2, A3, A4, A5)> CallbackType;
CallbackList() {}
void Notify(typename internal::CallbackParamTraits<A1>::ForwardType a1,
typename internal::CallbackParamTraits<A2>::ForwardType a2,
typename internal::CallbackParamTraits<A3>::ForwardType a3,
typename internal::CallbackParamTraits<A4>::ForwardType a4,
typename internal::CallbackParamTraits<A5>::ForwardType a5) {
typename internal::CallbackListBase<CallbackType>::Iterator it =
this->GetIterator();
CallbackType* cb;
while ((cb = it.GetNext()) != NULL) {
cb->Run(a1, a2, a3, a4, a5);
}
}
private:
DISALLOW_COPY_AND_ASSIGN(CallbackList);
};
template <typename A1, typename A2, typename A3, typename A4, typename A5,
typename A6>
class CallbackList<void(A1, A2, A3, A4, A5, A6)>
: public internal::CallbackListBase<Callback<void(A1, A2, A3, A4, A5,
A6)> > {
public:
typedef Callback<void(A1, A2, A3, A4, A5, A6)> CallbackType;
CallbackList() {}
void Notify(typename internal::CallbackParamTraits<A1>::ForwardType a1,
typename internal::CallbackParamTraits<A2>::ForwardType a2,
typename internal::CallbackParamTraits<A3>::ForwardType a3,
typename internal::CallbackParamTraits<A4>::ForwardType a4,
typename internal::CallbackParamTraits<A5>::ForwardType a5,
typename internal::CallbackParamTraits<A6>::ForwardType a6) {
typename internal::CallbackListBase<CallbackType>::Iterator it =
this->GetIterator();
CallbackType* cb;
while ((cb = it.GetNext()) != NULL) {
cb->Run(a1, a2, a3, a4, a5, a6);
}
}
private:
DISALLOW_COPY_AND_ASSIGN(CallbackList);
};
template <typename A1, typename A2, typename A3, typename A4, typename A5,
typename A6, typename A7>
class CallbackList<void(A1, A2, A3, A4, A5, A6, A7)>
: public internal::CallbackListBase<Callback<void(A1, A2, A3, A4, A5, A6,
A7)> > {
public:
typedef Callback<void(A1, A2, A3, A4, A5, A6, A7)> CallbackType;
CallbackList() {}
void Notify(typename internal::CallbackParamTraits<A1>::ForwardType a1,
typename internal::CallbackParamTraits<A2>::ForwardType a2,
typename internal::CallbackParamTraits<A3>::ForwardType a3,
typename internal::CallbackParamTraits<A4>::ForwardType a4,
typename internal::CallbackParamTraits<A5>::ForwardType a5,
typename internal::CallbackParamTraits<A6>::ForwardType a6,
typename internal::CallbackParamTraits<A7>::ForwardType a7) {
typename internal::CallbackListBase<CallbackType>::Iterator it =
this->GetIterator();
CallbackType* cb;
while ((cb = it.GetNext()) != NULL) {
cb->Run(a1, a2, a3, a4, a5, a6, a7);
}
}
private:
DISALLOW_COPY_AND_ASSIGN(CallbackList);
};
} // namespace base
#endif // !BUILDING_CEF_SHARED
#endif // CEF_INCLUDE_BASE_CEF_CALLBACK_LIST_H_