1 files changed, 142 insertions, 0 deletions
diff --git a/dom/cache/CacheStreamControlChild.cpp b/dom/cache/CacheStreamControlChild.cpp
new file mode 100644
index 0000000000..26b11e7f46
--- /dev/null
+++ b/dom/cache/CacheStreamControlChild.cpp
@@ -0,0 +1,142 @@
+/* -*- 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