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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 "CacheStreamControlChild.h"
#include "mozilla/Unused.h"
#include "mozilla/dom/cache/ActorUtils.h"
#include "mozilla/dom/cache/CacheTypes.h"
#include "mozilla/dom/cache/CacheWorkerRef.h"
#include "mozilla/ipc/IPCStreamUtils.h"
#include "mozilla/ipc/PBackgroundChild.h"
#include "nsISupportsImpl.h"
namespace mozilla::dom::cache {
using mozilla::ipc::FileDescriptor;
// declared in ActorUtils.h
already_AddRefed<PCacheStreamControlChild> AllocPCacheStreamControlChild() {
return MakeAndAddRef<CacheStreamControlChild>();
}
CacheStreamControlChild::CacheStreamControlChild()
: mDestroyStarted(false), mDestroyDelayed(false) {
MOZ_COUNT_CTOR(cache::CacheStreamControlChild);
}
CacheStreamControlChild::~CacheStreamControlChild() {
NS_ASSERT_OWNINGTHREAD(CacheStreamControlChild);
MOZ_COUNT_DTOR(cache::CacheStreamControlChild);
}
void CacheStreamControlChild::StartDestroy() {
NS_ASSERT_OWNINGTHREAD(CacheStreamControlChild);
// This can get called twice under some circumstances. For example, if the
// actor is added to a CacheWorkerRef that has already been notified and
// the Cache actor has no mListener.
if (mDestroyStarted) {
return;
}
mDestroyStarted = true;
// If any of the streams have started to be read, then wait for them to close
// naturally.
if (HasEverBeenRead()) {
// Note that we are delaying so that we can re-check for active streams
// in NoteClosedAfterForget().
mDestroyDelayed = true;
return;
}
// Otherwise, if the streams have not been touched then just pre-emptively
// close them now. This handles the case where someone retrieves a Response
// from the Cache, but never accesses the body. We should not keep the
// Worker alive until that Response is GC'd just because of its ignored
// body stream.
// Begin shutting down all streams. This is the same as if the parent had
// asked us to shutdown. So simulate the CloseAll IPC message.
RecvCloseAll();
}
void CacheStreamControlChild::SerializeControl(
CacheReadStream* aReadStreamOut) {
NS_ASSERT_OWNINGTHREAD(CacheStreamControlChild);
MOZ_DIAGNOSTIC_ASSERT(aReadStreamOut);
aReadStreamOut->control() = this;
}
void CacheStreamControlChild::SerializeStream(CacheReadStream* aReadStreamOut,
nsIInputStream* aStream) {
NS_ASSERT_OWNINGTHREAD(CacheStreamControlChild);
MOZ_DIAGNOSTIC_ASSERT(aReadStreamOut);
MOZ_ALWAYS_TRUE(mozilla::ipc::SerializeIPCStream(
do_AddRef(aStream), aReadStreamOut->stream(), /* aAllowLazy */ false));
}
void CacheStreamControlChild::OpenStream(const nsID& aId,
InputStreamResolver&& aResolver) {
NS_ASSERT_OWNINGTHREAD(CacheStreamControlChild);
if (mDestroyStarted) {
aResolver(nullptr);
return;
}
// If we are on a worker, then we need to hold it alive until the async
// IPC operation below completes. While the IPC layer will trigger a
// rejection here in many cases, we must handle the case where the
// MozPromise resolve runnable is already in the event queue when the
// worker wants to shut down.
const SafeRefPtr<CacheWorkerRef> holder = GetWorkerRefPtr().clonePtr();
SendOpenStream(aId)->Then(
GetCurrentSerialEventTarget(), __func__,
[aResolver,
holder = holder.clonePtr()](const Maybe<IPCStream>& aOptionalStream) {
nsCOMPtr<nsIInputStream> stream = DeserializeIPCStream(aOptionalStream);
aResolver(std::move(stream));
},
[aResolver, holder = holder.clonePtr()](ResponseRejectReason&& aReason) {
aResolver(nullptr);
});
}
void CacheStreamControlChild::NoteClosedAfterForget(const nsID& aId) {
NS_ASSERT_OWNINGTHREAD(CacheStreamControlChild);
QM_WARNONLY_TRY(OkIf(SendNoteClosed(aId)));
// A stream has closed. If we delayed StartDestry() due to this stream
// being read, then we should check to see if any of the remaining streams
// are active. If none of our other streams have been read, then we can
// proceed with the shutdown now.
if (mDestroyDelayed && !HasEverBeenRead()) {
mDestroyDelayed = false;
RecvCloseAll();
}
}
#ifdef DEBUG
void CacheStreamControlChild::AssertOwningThread() {
NS_ASSERT_OWNINGTHREAD(CacheStreamControlChild);
}
#endif
void CacheStreamControlChild::ActorDestroy(ActorDestroyReason aReason) {
NS_ASSERT_OWNINGTHREAD(CacheStreamControlChild);
CloseAllReadStreamsWithoutReporting();
RemoveWorkerRef();
}
mozilla::ipc::IPCResult CacheStreamControlChild::RecvCloseAll() {
NS_ASSERT_OWNINGTHREAD(CacheStreamControlChild);
CloseAllReadStreams();
return IPC_OK();
}
} // namespace mozilla::dom::cache