gecko-dev/dom/serviceworkers/ServiceWorkerJobQueue.cpp

121 lines
3.4 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/. */
#include "ServiceWorkerJobQueue.h"
#include "nsThreadUtils.h"
#include "ServiceWorkerJob.h"
#include "mozilla/dom/WorkerCommon.h"
namespace mozilla::dom {
class ServiceWorkerJobQueue::Callback final
: public ServiceWorkerJob::Callback {
RefPtr<ServiceWorkerJobQueue> mQueue;
~Callback() = default;
public:
explicit Callback(ServiceWorkerJobQueue* aQueue) : mQueue(aQueue) {
MOZ_ASSERT(NS_IsMainThread());
MOZ_ASSERT(mQueue);
}
virtual void JobFinished(ServiceWorkerJob* aJob,
ErrorResult& aStatus) override {
MOZ_ASSERT(NS_IsMainThread());
mQueue->JobFinished(aJob);
}
virtual void JobDiscarded(ErrorResult&) override {
// no-op; nothing to do.
}
NS_INLINE_DECL_REFCOUNTING(ServiceWorkerJobQueue::Callback, override)
};
ServiceWorkerJobQueue::~ServiceWorkerJobQueue() {
MOZ_ASSERT(NS_IsMainThread());
MOZ_ASSERT(mJobList.IsEmpty());
}
void ServiceWorkerJobQueue::JobFinished(ServiceWorkerJob* aJob) {
MOZ_ASSERT(NS_IsMainThread());
MOZ_ASSERT(aJob);
// XXX There are some corner cases where jobs can double-complete. Until
// we track all these down we do a non-fatal assert in debug builds and
// a runtime check to verify the queue is in the correct state.
NS_ASSERTION(!mJobList.IsEmpty(),
"Job queue should contain the job that just completed.");
NS_ASSERTION(mJobList.SafeElementAt(0, nullptr) == aJob,
"Job queue should contain the job that just completed.");
if (NS_WARN_IF(mJobList.SafeElementAt(0, nullptr) != aJob)) {
return;
}
mJobList.RemoveElementAt(0);
if (mJobList.IsEmpty()) {
return;
}
RunJob();
}
void ServiceWorkerJobQueue::RunJob() {
MOZ_ASSERT(NS_IsMainThread());
MOZ_ASSERT(!mJobList.IsEmpty());
MOZ_ASSERT(mJobList[0]->GetState() == ServiceWorkerJob::State::Initial);
RefPtr<Callback> callback = new Callback(this);
mJobList[0]->Start(callback);
}
ServiceWorkerJobQueue::ServiceWorkerJobQueue() {
MOZ_ASSERT(NS_IsMainThread());
}
void ServiceWorkerJobQueue::ScheduleJob(ServiceWorkerJob* aJob) {
MOZ_ASSERT(NS_IsMainThread());
MOZ_ASSERT(aJob);
MOZ_ASSERT(!mJobList.Contains(aJob));
if (mJobList.IsEmpty()) {
mJobList.AppendElement(aJob);
RunJob();
return;
}
MOZ_ASSERT(mJobList[0]->GetState() == ServiceWorkerJob::State::Started);
RefPtr<ServiceWorkerJob>& tailJob = mJobList[mJobList.Length() - 1];
if (!tailJob->ResultCallbacksInvoked() && aJob->IsEquivalentTo(tailJob)) {
tailJob->StealResultCallbacksFrom(aJob);
return;
}
mJobList.AppendElement(aJob);
}
void ServiceWorkerJobQueue::CancelAll() {
MOZ_ASSERT(NS_IsMainThread());
for (RefPtr<ServiceWorkerJob>& job : mJobList) {
job->Cancel();
}
// Remove jobs that are queued but not started since they should never
// run after being canceled. This means throwing away all jobs except
// for the job at the front of the list.
if (!mJobList.IsEmpty()) {
MOZ_ASSERT(mJobList[0]->GetState() == ServiceWorkerJob::State::Started);
mJobList.TruncateLength(1);
}
}
} // namespace mozilla::dom