/* -*- 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_AbortFollower_h
#define mozilla_dom_AbortFollower_h
#include "jsapi.h"
#include "nsISupportsImpl.h"
#include "nsTObserverArray.h"
#include "mozilla/WeakPtr.h"
namespace mozilla::dom {
class AbortSignal;
class AbortSignalImpl;
// This class must be implemented by objects who want to follow an
// AbortSignalImpl.
class AbortFollower :
public nsISupports {
public:
virtual void RunAbortAlgorithm() = 0;
// This adds strong reference to this follower on the signal, which means
// you'll need to call Unfollow() to prevent your object from living
// needlessly longer.
void Follow(AbortSignalImpl* aSignal);
// Explicitly call this to let garbage collection happen sooner when the
// follower finished its work and cannot be aborted anymore.
void Unfollow();
bool IsFollowing()
const;
AbortSignalImpl* Signal()
const {
return mFollowingSignal; }
protected:
virtual ~AbortFollower();
friend class AbortSignalImpl;
WeakPtr<AbortSignalImpl> mFollowingSignal;
};
/*
* TODO(krosylight): The only consumer of this is Fetch. It would be nice to
* merge this back to AbortSignal as it's quite a duplication right now.
*
* AbortSignalImpl is a minimal implementation without an associated global
* and without event dispatching, those are added in AbortSignal.
* See Bug 1478101
*/
class AbortSignalImpl :
public nsISupports,
public SupportsWeakPtr {
public:
explicit AbortSignalImpl(
bool aAborted, JS::Handle<JS::Value> aReason);
bool Aborted()
const;
// Web IDL Layer
void GetReason(JSContext* aCx, JS::MutableHandle<JS::Value> aReason);
// Helper for other DOM code
JS::Value RawReason()
const;
void SignalAbort(JS::Handle<JS::Value> aReason);
protected:
// Subclasses of this class must call these Traverse and Unlink functions
// during corresponding cycle collection operations.
static void Traverse(AbortSignalImpl* aSignal,
nsCycleCollectionTraversalCallback& cb);
static void Unlink(AbortSignalImpl* aSignal);
virtual ~AbortSignalImpl() { UnlinkFollowers(); }
virtual void SignalAbortWithDependents();
virtual void RunAbortSteps();
void SetAborted(JS::Handle<JS::Value> aReason);
JS::Heap<JS::Value> mReason;
private:
friend class AbortFollower;
void MaybeAssignAbortError(JSContext* aCx);
void UnlinkFollowers();
// TODO(krosylight): We should rename all names around the term "Follow". See
// bug 1873648.
//
// |AbortFollower::Follow| adds to this array, and
// |AbortFollower::Unfollow| (also called by the destructor) will remove
// from this array. Finally, calling |SignalAbort()| will (after running all
// abort algorithms) empty this and make all contained followers |Unfollow()|.
nsTObserverArray<RefPtr<AbortFollower>> mFollowers;
bool mAborted;
};
}
// namespace mozilla::dom
#endif // mozilla_dom_AbortFollower_h
