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/* -*- 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/. */
#include "mozilla/dom/cache/CacheChild.h"
#include "mozilla/Unused.h"
#include "mozilla/dom/cache/ActorUtils.h"
#include "mozilla/dom/cache/Cache.h"
#include "mozilla/dom/cache/CacheOpChild.h"
#include "CacheWorkerRef.h"
namespace mozilla::dom::cache {
// Declared in ActorUtils.h
PCacheChild* AllocPCacheChild() { return new CacheChild(); }
// Declared in ActorUtils.h
void DeallocPCacheChild(PCacheChild* aActor) { delete aActor; }
CacheChild::CacheChild()
: mListener(nullptr),
mNumChildActors(0),
mDelayedDestroy(false),
mLocked(false) {
MOZ_COUNT_CTOR(cache::CacheChild);
}
CacheChild::~CacheChild() {
MOZ_COUNT_DTOR(cache::CacheChild);
NS_ASSERT_OWNINGTHREAD(CacheChild);
MOZ_DIAGNOSTIC_ASSERT(!mListener);
MOZ_DIAGNOSTIC_ASSERT(!mNumChildActors);
MOZ_DIAGNOSTIC_ASSERT(!mLocked);
}
void CacheChild::SetListener(Cache* aListener) {
NS_ASSERT_OWNINGTHREAD(CacheChild);
MOZ_DIAGNOSTIC_ASSERT(!mListener);
mListener = aListener;
MOZ_DIAGNOSTIC_ASSERT(mListener);
}
void CacheChild::ClearListener() {
NS_ASSERT_OWNINGTHREAD(CacheChild);
MOZ_DIAGNOSTIC_ASSERT(mListener);
mListener = nullptr;
}
void CacheChild::ExecuteOp(nsIGlobalObject* aGlobal, Promise* aPromise,
nsISupports* aParent, const CacheOpArgs& aArgs) {
mNumChildActors += 1;
MOZ_ALWAYS_TRUE(
SendPCacheOpConstructor(new CacheOpChild(GetWorkerRefPtr().clonePtr(),
aGlobal, aParent, aPromise),
aArgs));
}
void CacheChild::StartDestroyFromListener() {
NS_ASSERT_OWNINGTHREAD(CacheChild);
// The listener should be held alive by any async operations, so if it
// is going away then there must not be any child actors. This in turn
// ensures that StartDestroy() will not trigger the delayed path.
MOZ_DIAGNOSTIC_ASSERT(!mNumChildActors);
StartDestroy();
}
void CacheChild::StartDestroy() {
NS_ASSERT_OWNINGTHREAD(CacheChild);
// If we have outstanding child actors, then don't destroy ourself yet.
// The child actors should be short lived and we should allow them to complete
// if possible. NoteDeletedActor() will call back into this Shutdown()
// method when the last child actor is gone. Also, delay destruction if we
// have been explicitly locked by someone using us on the stack.
if (mNumChildActors || mLocked) {
mDelayedDestroy = true;
return;
}
RefPtr<Cache> listener = mListener;
// StartDestroy() can get called from either Cache or the WorkerRef.
// Theoretically we can get double called if the right race happens. Handle
// that by just ignoring the second StartDestroy() call.
if (!listener) {
return;
}
listener->DestroyInternal(this);
// Cache listener should call ClearListener() in DestroyInternal()
MOZ_DIAGNOSTIC_ASSERT(!mListener);
// Start actor destruction from parent process
QM_WARNONLY_TRY(OkIf(SendTeardown()));
}
void CacheChild::ActorDestroy(ActorDestroyReason aReason) {
NS_ASSERT_OWNINGTHREAD(CacheChild);
RefPtr<Cache> listener = mListener;
if (listener) {
listener->DestroyInternal(this);
// Cache listener should call ClearListener() in DestroyInternal()
MOZ_DIAGNOSTIC_ASSERT(!mListener);
}
RemoveWorkerRef();
}
PCacheOpChild* CacheChild::AllocPCacheOpChild(const CacheOpArgs& aOpArgs) {
MOZ_CRASH("CacheOpChild should be manually constructed.");
return nullptr;
}
bool CacheChild::DeallocPCacheOpChild(PCacheOpChild* aActor) {
delete aActor;
NoteDeletedActor();
return true;
}
void CacheChild::NoteDeletedActor() {
mNumChildActors -= 1;
MaybeFlushDelayedDestroy();
}
void CacheChild::MaybeFlushDelayedDestroy() {
if (!mNumChildActors && !mLocked && mDelayedDestroy) {
StartDestroy();
}
}
void CacheChild::Lock() {
NS_ASSERT_OWNINGTHREAD(CacheChild);
MOZ_DIAGNOSTIC_ASSERT(!mLocked);
mLocked = true;
}
void CacheChild::Unlock() {
NS_ASSERT_OWNINGTHREAD(CacheChild);
MOZ_DIAGNOSTIC_ASSERT(mLocked);
mLocked = false;
MaybeFlushDelayedDestroy();
}
} // namespace mozilla::dom::cache