IDBCursor.h
/* -*- 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/. */
#ifndef mozilla_dom_idbcursor_h__
#define mozilla_dom_idbcursor_h__
#include "IDBCursorType.h"
#include "IndexedDatabase.h"
#include "js/RootingAPI.h"
#include "mozilla/Attributes.h"
#include "mozilla/dom/IDBCursorBinding.h"
#include "mozilla/dom/IDBTransaction.h"
#include "mozilla/dom/indexedDB/Key.h"
#include "mozilla/dom/quota/CheckedUnsafePtr.h"
#include "mozilla/InitializedOnce.h"
#include "nsCycleCollectionParticipant.h"
#include "nsWrapperCache.h"
class nsIGlobalObject;
namespace mozilla {
class ErrorResult;
namespace dom {
class IDBIndex;
class IDBObjectStore;
class IDBRequest;
class OwningIDBObjectStoreOrIDBIndex;
class IDBObjectStoreCursor;
class IDBObjectStoreKeyCursor;
class IDBIndexCursor;
class IDBIndexKeyCursor;
namespace indexedDB {
class BackgroundCursorChildBase;
template <IDBCursorType CursorType>
class BackgroundCursorChild;
} // namespace indexedDB
class IDBCursor : public nsISupports, public nsWrapperCache {
public:
using Key = indexedDB::Key;
using StructuredCloneReadInfoChild = indexedDB::StructuredCloneReadInfoChild;
using Direction = IDBCursorDirection;
using Type = IDBCursorType;
protected:
InitializedOnce<const NotNull<indexedDB::BackgroundCursorChildBase*>>
mBackgroundActor;
// TODO: mRequest could be made const if Bug 1575173 is resolved. It is
// initialized in the constructor and never modified/cleared.
RefPtr<IDBRequest> mRequest;
// Sub-classes' mSource will hold this alive.
CheckedUnsafePtr<IDBTransaction> mTransaction;
protected:
// These are cycle-collected!
JS::Heap<JS::Value> mCachedKey;
JS::Heap<JS::Value> mCachedPrimaryKey;
JS::Heap<JS::Value> mCachedValue;
const Direction mDirection;
bool mHaveCachedKey : 1;
bool mHaveCachedPrimaryKey : 1;
bool mHaveCachedValue : 1;
bool mRooted : 1;
bool mContinueCalled : 1;
bool mHaveValue : 1;
public:
[[nodiscard]] static RefPtr<IDBObjectStoreCursor> Create(
indexedDB::BackgroundCursorChild<Type::ObjectStore>* aBackgroundActor,
Key aKey, StructuredCloneReadInfoChild&& aCloneInfo);
[[nodiscard]] static RefPtr<IDBObjectStoreKeyCursor> Create(
indexedDB::BackgroundCursorChild<Type::ObjectStoreKey>* aBackgroundActor,
Key aKey);
[[nodiscard]] static RefPtr<IDBIndexCursor> Create(
indexedDB::BackgroundCursorChild<Type::Index>* aBackgroundActor, Key aKey,
Key aSortKey, Key aPrimaryKey, StructuredCloneReadInfoChild&& aCloneInfo);
[[nodiscard]] static RefPtr<IDBIndexKeyCursor> Create(
indexedDB::BackgroundCursorChild<Type::IndexKey>* aBackgroundActor,
Key aKey, Key aSortKey, Key aPrimaryKey);
void AssertIsOnOwningThread() const
#ifdef DEBUG
;
#else
{
}
#endif
nsIGlobalObject* GetParentObject() const;
// XXX: The virtual methods that are used by the DOM binding could be removed
// on the base class, if we provided a non-polymorphic wrapper instead, which
// uses a custom dispatch to the actual implementation type. Don't know if
// this is worth it.
virtual void GetSource(OwningIDBObjectStoreOrIDBIndex& aSource) const = 0;
IDBCursorDirection GetDirection() const;
RefPtr<IDBRequest> Request() const;
virtual void GetKey(JSContext* aCx, JS::MutableHandle<JS::Value> aResult,
ErrorResult& aRv) = 0;
virtual void GetPrimaryKey(JSContext* aCx,
JS::MutableHandle<JS::Value> aResult,
ErrorResult& aRv) = 0;
// XXX: We could move this to a sub-class, since this is only present on
// IDBCursorWithValue.
virtual void GetValue(JSContext* aCx, JS::MutableHandle<JS::Value> aResult,
ErrorResult& aRv) = 0;
virtual void Continue(JSContext* aCx, JS::Handle<JS::Value> aKey,
ErrorResult& aRv) = 0;
virtual void ContinuePrimaryKey(JSContext* aCx, JS::Handle<JS::Value> aKey,
JS::Handle<JS::Value> aPrimaryKey,
ErrorResult& aRv) = 0;
virtual void Advance(uint32_t aCount, ErrorResult& aRv) = 0;
[[nodiscard]] virtual RefPtr<IDBRequest> Update(JSContext* aCx,
JS::Handle<JS::Value> aValue,
ErrorResult& aRv) = 0;
[[nodiscard]] virtual RefPtr<IDBRequest> Delete(JSContext* aCx,
ErrorResult& aRv) = 0;
void ClearBackgroundActor() {
AssertIsOnOwningThread();
mBackgroundActor.destroy();
}
virtual void InvalidateCachedResponses() = 0;
NS_DECL_CYCLE_COLLECTING_ISUPPORTS
NS_DECL_CYCLE_COLLECTION_SCRIPT_HOLDER_CLASS(IDBCursor)
protected:
IDBCursor(indexedDB::BackgroundCursorChildBase* aBackgroundActor);
// TODO: Check if we can remove virtual by changing cycle collection.
virtual ~IDBCursor() = default;
void ResetBase();
};
template <IDBCursor::Type CursorType>
class IDBTypedCursor : public IDBCursor {
public:
template <typename... DataArgs>
explicit IDBTypedCursor(
indexedDB::BackgroundCursorChild<CursorType>* aBackgroundActor,
DataArgs&&... aDataArgs);
static constexpr Type GetType() { return CursorType; }
// Checks if this is a locale aware cursor (ie. the index's sortKey is unset)
bool IsLocaleAware() const;
void GetSource(OwningIDBObjectStoreOrIDBIndex& aSource) const final;
void GetKey(JSContext* aCx, JS::MutableHandle<JS::Value> aResult,
ErrorResult& aRv) final;
void GetPrimaryKey(JSContext* aCx, JS::MutableHandle<JS::Value> aResult,
ErrorResult& aRv) final;
void GetValue(JSContext* aCx, JS::MutableHandle<JS::Value> aResult,
ErrorResult& aRv) final;
void Continue(JSContext* aCx, JS::Handle<JS::Value> aKey,
ErrorResult& aRv) final;
void ContinuePrimaryKey(JSContext* aCx, JS::Handle<JS::Value> aKey,
JS::Handle<JS::Value> aPrimaryKey,
ErrorResult& aRv) final;
void Advance(uint32_t aCount, ErrorResult& aRv) final;
[[nodiscard]] RefPtr<IDBRequest> Update(JSContext* aCx,
JS::Handle<JS::Value> aValue,
ErrorResult& aRv) final;
[[nodiscard]] RefPtr<IDBRequest> Delete(JSContext* aCx,
ErrorResult& aRv) final;
// nsWrapperCache
JSObject* WrapObject(JSContext* aCx, JS::Handle<JSObject*> aGivenProto) final;
void InvalidateCachedResponses() final;
void Reset();
void Reset(CursorData<CursorType>&& aCursorData);
private:
static constexpr bool IsObjectStoreCursor =
CursorTypeTraits<CursorType>::IsObjectStoreCursor;
static constexpr bool IsKeyOnlyCursor =
CursorTypeTraits<CursorType>::IsKeyOnlyCursor;
CursorSourceType<CursorType>& GetSourceRef() const {
MOZ_ASSERT(mSource);
return *mSource;
}
IDBObjectStore& GetSourceObjectStoreRef() const {
if constexpr (IsObjectStoreCursor) {
return GetSourceRef();
} else {
MOZ_ASSERT(!GetSourceRef().IsDeleted());
auto res = GetSourceRef().ObjectStore();
MOZ_ASSERT(res);
return *res;
}
}
indexedDB::BackgroundCursorChild<CursorType>& GetTypedBackgroundActorRef()
const {
// We can safely downcast to BackgroundCursorChild<CursorType>*, since we
// initialized that in the constructor from that type. We just want to avoid
// having a second typed field.
return *static_cast<indexedDB::BackgroundCursorChild<CursorType>*>(
mBackgroundActor->get());
}
bool IsSourceDeleted() const;
protected:
virtual ~IDBTypedCursor() override;
void DropJSObjects();
CursorData<CursorType> mData;
// TODO: mSource could be made const if Bug 1575173 is resolved. It is
// initialized in the constructor and never modified/cleared.
RefPtr<CursorSourceType<CursorType>> mSource;
};
// The subclasses defined by this macro are only needed to be able to use the
// cycle collector macros, which do not support templates. If spelled out, the
// cycle collection could be implemented directly on IDBTypedCursor, and these
// classes were not needed.
#define CONCRETE_IDBCURSOR_SUBCLASS(_subclassName, _cursorType) \
class _subclassName final : public IDBTypedCursor<_cursorType> { \
public: \
NS_DECL_ISUPPORTS_INHERITED \
NS_DECL_CYCLE_COLLECTION_CLASS_INHERITED(_subclassName, IDBCursor) \
\
using IDBTypedCursor<_cursorType>::IDBTypedCursor; \
\
private: \
~_subclassName() final = default; \
};
CONCRETE_IDBCURSOR_SUBCLASS(IDBObjectStoreCursor, IDBCursor::Type::ObjectStore)
CONCRETE_IDBCURSOR_SUBCLASS(IDBObjectStoreKeyCursor,
IDBCursor::Type::ObjectStoreKey)
CONCRETE_IDBCURSOR_SUBCLASS(IDBIndexCursor, IDBCursor::Type::Index)
CONCRETE_IDBCURSOR_SUBCLASS(IDBIndexKeyCursor, IDBCursor::Type::IndexKey)
template <IDBCursor::Type CursorType>
using IDBCursorImpl = typename CursorTypeTraits<CursorType>::Type;
} // namespace dom
} // namespace mozilla
#endif // mozilla_dom_idbcursor_h__
