dom/cache/CacheWorkerRef.cpp

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
   3 /* This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 #include "mozilla/dom/cache/CacheWorkerRef.h"
   8
   9 #include "mozilla/dom/cache/ActorChild.h"
  10 #include "mozilla/dom/WorkerPrivate.h"
  11 #include "mozilla/dom/WorkerRef.h"
  12
  13 namespace mozilla::dom::cache {
  14
  15 // static
  16 SafeRefPtr<CacheWorkerRef> CacheWorkerRef::Create(WorkerPrivate* aWorkerPrivate,
  17                                                   Behavior aBehavior) {
  18   MOZ_DIAGNOSTIC_ASSERT(aWorkerPrivate);
  19
  20   // XXX This looks as if this could be simplified now by moving into the ctor
  21   // of CacheWorkerRef, since we can now use SafeRefPtrFromThis in the ctor
  22   auto workerRef =
  23       MakeSafeRefPtr<CacheWorkerRef>(aBehavior, ConstructorGuard{});
  24   auto notify = [workerRef = workerRef.clonePtr()] { workerRef->Notify(); };
  25   if (aBehavior == eStrongWorkerRef) {
  26     workerRef->mStrongWorkerRef = StrongWorkerRef::Create(
  27         aWorkerPrivate, "CacheWorkerRef-Strong", std::move(notify));
  28   } else {
  29     MOZ_ASSERT(aBehavior == eIPCWorkerRef);
  30     workerRef->mIPCWorkerRef = IPCWorkerRef::Create(
  31         aWorkerPrivate, "CacheWorkerRef-IPC", std::move(notify));
  32   }
  33
  34   if (NS_WARN_IF(!workerRef->mIPCWorkerRef && !workerRef->mStrongWorkerRef)) {
  35     return nullptr;
  36   }
  37
  38   return workerRef;
  39 }
  40
  41 // static
  42 SafeRefPtr<CacheWorkerRef> CacheWorkerRef::PreferBehavior(
  43     SafeRefPtr<CacheWorkerRef> aCurrentRef, Behavior aBehavior) {
  44   if (!aCurrentRef) {
  45     return nullptr;
  46   }
  47
  48   SafeRefPtr<CacheWorkerRef> orig = std::move(aCurrentRef);
  49   if (orig->mBehavior == aBehavior) {
  50     return orig;
  51   }
  52
  53   WorkerPrivate* workerPrivate = nullptr;
  54   if (orig->mBehavior == eStrongWorkerRef) {
  55     workerPrivate = orig->mStrongWorkerRef->Private();
  56   } else {
  57     MOZ_ASSERT(orig->mBehavior == eIPCWorkerRef);
  58     workerPrivate = orig->mIPCWorkerRef->Private();
  59   }
  60
  61   MOZ_ASSERT(workerPrivate);
  62
  63   SafeRefPtr<CacheWorkerRef> replace = Create(workerPrivate, aBehavior);
  64   return static_cast<bool>(replace) ? std::move(replace) : std::move(orig);
  65 }
  66
  67 void CacheWorkerRef::AddActor(ActorChild& aActor) {
  68   NS_ASSERT_OWNINGTHREAD(CacheWorkerRef);
  69   MOZ_ASSERT(!mActorList.Contains(&aActor));
  70
  71   mActorList.AppendElement(WrapNotNullUnchecked(&aActor));
  72   if (mBehavior == eIPCWorkerRef) {
  73     MOZ_ASSERT(mIPCWorkerRef);
  74     mIPCWorkerRef->SetActorCount(mActorList.Length());
  75   }
  76
  77   // Allow an actor to be added after we've entered the Notifying case.  We
  78   // can't stop the actor creation from racing with out destruction of the
  79   // other actors and we need to wait for this extra one to close as well.
  80   // Signal it should destroy itself right away.
  81   if (mNotified) {
  82     aActor.StartDestroy();
  83   }
  84 }
  85
  86 void CacheWorkerRef::RemoveActor(ActorChild& aActor) {
  87   NS_ASSERT_OWNINGTHREAD(CacheWorkerRef);
  88
  89 #if defined(RELEASE_OR_BETA)
  90   mActorList.RemoveElement(&aActor);
  91 #else
  92   MOZ_DIAGNOSTIC_ASSERT(mActorList.RemoveElement(&aActor));
  93 #endif
  94
  95   MOZ_ASSERT(!mActorList.Contains(&aActor));
  96
  97   if (mBehavior == eIPCWorkerRef) {
  98     MOZ_ASSERT(mIPCWorkerRef);
  99     mIPCWorkerRef->SetActorCount(mActorList.Length());
 100   }
 101
 102   if (mActorList.IsEmpty()) {
 103     mStrongWorkerRef = nullptr;
 104     mIPCWorkerRef = nullptr;
 105   }
 106 }
 107
 108 bool CacheWorkerRef::Notified() const { return mNotified; }
 109
 110 void CacheWorkerRef::Notify() {
 111   NS_ASSERT_OWNINGTHREAD(CacheWorkerRef);
 112
 113   mNotified = true;
 114
 115   // Start the asynchronous destruction of our actors.  These will call back
 116   // into RemoveActor() once the actor is destroyed.
 117   for (const auto& actor : mActorList) {
 118     actor->StartDestroy();
 119   }
 120 }
 121
 122 CacheWorkerRef::CacheWorkerRef(Behavior aBehavior, ConstructorGuard)
 123     : mBehavior(aBehavior), mNotified(false) {}
 124
 125 CacheWorkerRef::~CacheWorkerRef() {
 126   NS_ASSERT_OWNINGTHREAD(CacheWorkerRef);
 127   MOZ_DIAGNOSTIC_ASSERT(mActorList.IsEmpty());
 128 }
 129
 130 }  // namespace mozilla::dom::cache