DXR is a code search and navigation tool aimed at making sense of large projects. It supports full-text and regex searches as well as structural queries.

Header

Mercurial (441520899d5f)

VCS Links

Line Code
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220
/* -*- 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 "WorkerRef.h"

#include "mozilla/Unused.h"
#include "WorkerHolder.h"
#include "WorkerRunnable.h"
#include "WorkerPrivate.h"

namespace mozilla {
namespace dom {

namespace {

// This runnable is used to release the StrongWorkerRef on the worker thread
// when a ThreadSafeWorkerRef is released.
class ReleaseRefControlRunnable final : public WorkerControlRunnable {
 public:
  ReleaseRefControlRunnable(WorkerPrivate* aWorkerPrivate,
                            already_AddRefed<StrongWorkerRef> aRef)
      : WorkerControlRunnable(aWorkerPrivate, WorkerThreadUnchangedBusyCount),
        mRef(std::move(aRef)) {
    MOZ_ASSERT(mRef);
  }

  bool PreDispatch(WorkerPrivate* aWorkerPrivate) override { return true; }

  void PostDispatch(WorkerPrivate* aWorkerPrivate,
                    bool aDispatchResult) override {}

  bool WorkerRun(JSContext* aCx, WorkerPrivate* aWorkerPrivate) override {
    mRef = nullptr;
    return true;
  }

 private:
  RefPtr<StrongWorkerRef> mRef;
};

}  // namespace

// ----------------------------------------------------------------------------
// WorkerRef::Holder

class WorkerRef::Holder final : public mozilla::dom::WorkerHolder {
 public:
  Holder(const char* aName, WorkerRef* aWorkerRef, Behavior aBehavior)
      : mozilla::dom::WorkerHolder(aName, aBehavior), mWorkerRef(aWorkerRef) {}

  bool Notify(WorkerStatus aStatus) override {
    MOZ_ASSERT(mWorkerRef);

    if (aStatus < Canceling) {
      return true;
    }

    // Let's keep this object alive for the whole Notify() execution.
    RefPtr<WorkerRef> workerRef;
    workerRef = mWorkerRef;

    workerRef->Notify();
    return true;
  }

 public:
  WorkerRef* mWorkerRef;
};

// ----------------------------------------------------------------------------
// WorkerRef

WorkerRef::WorkerRef(WorkerPrivate* aWorkerPrivate)
    : mWorkerPrivate(aWorkerPrivate) {
  MOZ_ASSERT(aWorkerPrivate);
  aWorkerPrivate->AssertIsOnWorkerThread();
}

WorkerRef::~WorkerRef() { NS_ASSERT_OWNINGTHREAD(WorkerRef); }

void WorkerRef::Notify() {
  MOZ_ASSERT(mHolder);
  NS_ASSERT_OWNINGTHREAD(WorkerRef);

  if (!mCallback) {
    return;
  }

  std::function<void()> callback = std::move(mCallback);
  MOZ_ASSERT(!mCallback);

  callback();
}

// ----------------------------------------------------------------------------
// WeakWorkerRef

/* static */
already_AddRefed<WeakWorkerRef> WeakWorkerRef::Create(
    WorkerPrivate* aWorkerPrivate, std::function<void()>&& aCallback) {
  MOZ_ASSERT(aWorkerPrivate);
  aWorkerPrivate->AssertIsOnWorkerThread();

  RefPtr<WeakWorkerRef> ref = new WeakWorkerRef(aWorkerPrivate);

  // This holder doesn't keep the worker alive.
  UniquePtr<Holder> holder(new Holder("WeakWorkerRef::Holder", ref,
                                      WorkerHolder::AllowIdleShutdownStart));
  if (NS_WARN_IF(!holder->HoldWorker(aWorkerPrivate, Canceling))) {
    return nullptr;
  }

  ref->mHolder = std::move(holder);
  ref->mCallback = std::move(aCallback);

  return ref.forget();
}

WeakWorkerRef::WeakWorkerRef(WorkerPrivate* aWorkerPrivate)
    : WorkerRef(aWorkerPrivate) {}

WeakWorkerRef::~WeakWorkerRef() = default;

void WeakWorkerRef::Notify() {
  WorkerRef::Notify();

  mHolder = nullptr;
  mWorkerPrivate = nullptr;
}

WorkerPrivate* WeakWorkerRef::GetPrivate() const {
  NS_ASSERT_OWNINGTHREAD(WeakWorkerRef);
  return mWorkerPrivate;
}

WorkerPrivate* WeakWorkerRef::GetUnsafePrivate() const {
  return mWorkerPrivate;
}

// ----------------------------------------------------------------------------
// StrongWorkerRef

/* static */
already_AddRefed<StrongWorkerRef> StrongWorkerRef::Create(
    WorkerPrivate* const aWorkerPrivate, const char* const aName,
    std::function<void()>&& aCallback) {
  if (RefPtr<StrongWorkerRef> ref =
          CreateImpl(aWorkerPrivate, aName, Canceling)) {
    ref->mCallback = std::move(aCallback);
    return ref.forget();
  }
  return nullptr;
}

/* static */
already_AddRefed<StrongWorkerRef> StrongWorkerRef::CreateForcibly(
    WorkerPrivate* const aWorkerPrivate, const char* const aName) {
  return CreateImpl(aWorkerPrivate, aName, Killing);
}

/* static */
already_AddRefed<StrongWorkerRef> StrongWorkerRef::CreateImpl(
    WorkerPrivate* const aWorkerPrivate, const char* const aName,
    WorkerStatus const aFailStatus) {
  MOZ_ASSERT(aWorkerPrivate);
  MOZ_ASSERT(aName);

  RefPtr<StrongWorkerRef> ref = new StrongWorkerRef(aWorkerPrivate);

  // The worker is kept alive by this holder.
  UniquePtr<Holder> holder(
      new Holder(aName, ref, WorkerHolder::PreventIdleShutdownStart));
  if (NS_WARN_IF(!holder->HoldWorker(aWorkerPrivate, aFailStatus))) {
    return nullptr;
  }

  ref->mHolder = std::move(holder);

  return ref.forget();
}

StrongWorkerRef::StrongWorkerRef(WorkerPrivate* aWorkerPrivate)
    : WorkerRef(aWorkerPrivate) {}

StrongWorkerRef::~StrongWorkerRef() { NS_ASSERT_OWNINGTHREAD(StrongWorkerRef); }

WorkerPrivate* StrongWorkerRef::Private() const {
  MOZ_ASSERT(mHolder);
  NS_ASSERT_OWNINGTHREAD(StrongWorkerRef);
  return mWorkerPrivate;
}

// ----------------------------------------------------------------------------
// ThreadSafeWorkerRef

ThreadSafeWorkerRef::ThreadSafeWorkerRef(StrongWorkerRef* aRef) : mRef(aRef) {
  MOZ_ASSERT(aRef);
  aRef->Private()->AssertIsOnWorkerThread();
}

ThreadSafeWorkerRef::~ThreadSafeWorkerRef() {
  // Let's release the StrongWorkerRef on the correct thread.
  if (!mRef->mWorkerPrivate->IsOnWorkerThread()) {
    WorkerPrivate* workerPrivate = mRef->mWorkerPrivate;
    RefPtr<ReleaseRefControlRunnable> r =
        new ReleaseRefControlRunnable(workerPrivate, mRef.forget());
    r->Dispatch();
    return;
  }
}

WorkerPrivate* ThreadSafeWorkerRef::Private() const {
  return mRef->mWorkerPrivate;
}

}  // namespace dom
}  // namespace mozilla