gecko-dev/dom/base/AncestorIterator.h

110 строки
4.8 KiB
C++

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* 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/. */
/**
* Implementation of some generic iterators over ancestor nodes.
*
* Note that these keep raw pointers to the nodes they iterate from, and as
* such the DOM should not be mutated while they're in use. There are debug
* assertions (via nsMutationGuard) that check this in debug builds.
*/
#ifndef mozilla_dom_AncestorIterator_h
#define mozilla_dom_AncestorIterator_h
#include "nsINode.h"
#include "nsIContentInlines.h"
#include "FilteredNodeIterator.h"
namespace mozilla {
namespace dom {
#ifdef DEBUG
# define MUTATION_GUARD(class_name_) \
nsMutationGuard mMutationGuard; \
~class_name_() { MOZ_ASSERT(!mMutationGuard.Mutated(0)); }
#else
# define MUTATION_GUARD(class_name_)
#endif
#define DEFINE_ANCESTOR_ITERATOR(name_, method_) \
class Inclusive##name_ { \
using Self = Inclusive##name_; \
\
public: \
explicit Inclusive##name_(const nsINode& aNode) \
: mCurrent(const_cast<nsINode*>(&aNode)) {} \
Self& begin() { return *this; } \
std::nullptr_t end() const { return nullptr; } \
bool operator!=(std::nullptr_t) const { return !!mCurrent; } \
void operator++() { mCurrent = mCurrent->method_(); } \
nsINode* operator*() { return mCurrent; } \
\
MUTATION_GUARD(Inclusive##name_) \
\
protected: \
explicit Inclusive##name_(nsINode* aCurrent) : mCurrent(aCurrent) {} \
nsINode* mCurrent; \
}; \
class name_ : public Inclusive##name_ { \
public: \
using Super = Inclusive##name_; \
explicit name_(const nsINode& aNode) \
: Inclusive##name_(aNode.method_()) {} \
}; \
template <typename T> \
class name_##OfTypeIterator : public FilteredNodeIterator<T, name_> { \
public: \
explicit name_##OfTypeIterator(const nsINode& aNode) \
: FilteredNodeIterator<T, name_>(aNode) {} \
}; \
template <typename T> \
class Inclusive##name_##OfTypeIterator \
: public FilteredNodeIterator<T, Inclusive##name_> { \
public: \
explicit Inclusive##name_##OfTypeIterator(const nsINode& aNode) \
: FilteredNodeIterator<T, Inclusive##name_>(aNode) {} \
};
DEFINE_ANCESTOR_ITERATOR(Ancestors, GetParentNode)
DEFINE_ANCESTOR_ITERATOR(FlatTreeAncestors, GetFlattenedTreeParentNode)
#undef MUTATION_GUARD
} // namespace dom
} // namespace mozilla
template <typename T>
inline mozilla::dom::AncestorsOfTypeIterator<T> nsINode::AncestorsOfType()
const {
return mozilla::dom::AncestorsOfTypeIterator<T>(*this);
}
template <typename T>
inline mozilla::dom::InclusiveAncestorsOfTypeIterator<T>
nsINode::InclusiveAncestorsOfType() const {
return mozilla::dom::InclusiveAncestorsOfTypeIterator<T>(*this);
}
template <typename T>
inline mozilla::dom::FlatTreeAncestorsOfTypeIterator<T>
nsINode::FlatTreeAncestorsOfType() const {
return mozilla::dom::FlatTreeAncestorsOfTypeIterator<T>(*this);
}
template <typename T>
inline mozilla::dom::InclusiveFlatTreeAncestorsOfTypeIterator<T>
nsINode::InclusiveFlatTreeAncestorsOfType() const {
return mozilla::dom::InclusiveFlatTreeAncestorsOfTypeIterator<T>(*this);
}
template <typename T>
inline T* nsINode::FirstAncestorOfType() const {
return *(AncestorsOfType<T>());
}
#endif // mozilla_dom_AncestorIterator.h