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// Copyright (c) 2011 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "include/base/cef_weak_ptr.h"
namespace base {
namespace internal {
WeakReference::Flag::Flag() {
// Flags only become bound when checked for validity, or invalidated,
// so that we can check that later validity/invalidation operations on
// the same Flag take place on the same threadd thread.
thread_checker_.DetachFromThread();
}
void WeakReference::Flag::Invalidate() {
// The flag being invalidated with a single ref implies that there are no
// weak pointers in existence. Allow deletion on other thread in this case.
#if DCHECK_IS_ON()
DCHECK(thread_checker_.CalledOnValidThread() || HasOneRef())
<< "WeakPtrs must be invalidated on the same thread as where "
<< "they are bound.\n";
#endif
invalidated_.Set();
}
bool WeakReference::Flag::IsValid() const {
// WeakPtrs must be checked on the same threadd thread.
DCHECK(thread_checker_.CalledOnValidThread());
return !invalidated_.IsSet();
}
bool WeakReference::Flag::MaybeValid() const {
return !invalidated_.IsSet();
}
void WeakReference::Flag::DetachFromThread() {
thread_checker_.DetachFromThread();
}
WeakReference::Flag::~Flag() = default;
WeakReference::WeakReference() = default;
WeakReference::WeakReference(const scoped_refptr<Flag>& flag) : flag_(flag) {}
WeakReference::~WeakReference() = default;
WeakReference::WeakReference(WeakReference&& other) noexcept = default;
WeakReference::WeakReference(const WeakReference& other) = default;
bool WeakReference::IsValid() const {
return flag_ && flag_->IsValid();
}
bool WeakReference::MaybeValid() const {
return flag_ && flag_->MaybeValid();
}
WeakReferenceOwner::WeakReferenceOwner()
: flag_(MakeRefCounted<WeakReference::Flag>()) {}
WeakReferenceOwner::~WeakReferenceOwner() {
flag_->Invalidate();
}
WeakReference WeakReferenceOwner::GetRef() const {
// If we hold the last reference to the Flag then detach the ThreadChecker.
if (!HasRefs()) {
flag_->DetachFromThread();
}
return WeakReference(flag_);
}
void WeakReferenceOwner::Invalidate() {
flag_->Invalidate();
flag_ = MakeRefCounted<WeakReference::Flag>();
}
WeakPtrBase::WeakPtrBase() : ptr_(0) {}
WeakPtrBase::~WeakPtrBase() = default;
WeakPtrBase::WeakPtrBase(const WeakReference& ref, uintptr_t ptr)
: ref_(ref), ptr_(ptr) {
DCHECK(ptr_);
}
WeakPtrFactoryBase::WeakPtrFactoryBase(uintptr_t ptr) : ptr_(ptr) {
DCHECK(ptr_);
}
WeakPtrFactoryBase::~WeakPtrFactoryBase() {
ptr_ = 0;
}
} // namespace internal
} // namespace base
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