dom/ipc/JSOracleParent.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/JSOracleParent.h"
   8 #include "mozilla/ClearOnShutdown.h"
   9 #include "mozilla/RefPtr.h"
  10 #include "mozilla/dom/PJSOracle.h"
  11 #include "mozilla/ipc/Endpoint.h"
  12 #include "mozilla/ipc/UtilityProcessManager.h"
  13
  14 using namespace mozilla;
  15 using namespace mozilla::dom;
  16
  17 static StaticRefPtr<JSOracleParent> sOracleSingleton;
  18
  19 /* static */
  20 void JSOracleParent::WithJSOracle(
  21     const std::function<void(JSOracleParent* aParent)>& aCallback) {
  22   GetSingleton()->StartJSOracle()->Then(
  23       GetMainThreadSerialEventTarget(), __func__,
  24       [aCallback](const JSOraclePromise::ResolveOrRejectValue& aResult) {
  25         aCallback(aResult.IsReject() || !aResult.ResolveValue()
  26                       ? nullptr
  27                       : GetSingleton());
  28       });
  29 }
  30
  31 void JSOracleParent::ActorDestroy(ActorDestroyReason aReason) {
  32   // Given an actor can only be bound to one process,
  33   // if the utility process crashes and we create a new one,
  34   // we can't reuse the same JSOracleParent instance for it,
  35   // so we always create a new JSOracleParent to replace
  36   // the existing one.
  37   if (aReason == ActorDestroyReason::AbnormalShutdown) {
  38     sOracleSingleton = new JSOracleParent();
  39   }
  40 }
  41
  42 /* static */
  43 JSOracleParent* JSOracleParent::GetSingleton() {
  44   if (!sOracleSingleton) {
  45     sOracleSingleton = new JSOracleParent();
  46     ClearOnShutdown(&sOracleSingleton);
  47   }
  48
  49   return sOracleSingleton;
  50 }
  51
  52 RefPtr<JSOracleParent::JSOraclePromise> JSOracleParent::StartJSOracle() {
  53   using namespace mozilla::ipc;
  54   RefPtr<JSOracleParent> parent = JSOracleParent::GetSingleton();
  55   return UtilityProcessManager::GetSingleton()->StartJSOracle(parent);
  56 }
  57
  58 nsresult JSOracleParent::BindToUtilityProcess(
  59     const RefPtr<mozilla::ipc::UtilityProcessParent>& aUtilityParent) {
  60   Endpoint<PJSOracleParent> parentEnd;
  61   Endpoint<PJSOracleChild> childEnd;
  62   MOZ_ASSERT(aUtilityParent);
  63   if (NS_FAILED(PJSOracle::CreateEndpoints(base::GetCurrentProcId(),
  64                                            aUtilityParent->OtherPid(),
  65                                            &parentEnd, &childEnd))) {
  66     return NS_ERROR_FAILURE;
  67   }
  68
  69   if (!aUtilityParent->SendStartJSOracleService(std::move(childEnd))) {
  70     return NS_ERROR_FAILURE;
  71   }
  72
  73   Bind(std::move(parentEnd));
  74
  75   return NS_OK;
  76 }
  77
  78 void JSOracleParent::Bind(Endpoint<PJSOracleParent>&& aEndpoint) {
  79   DebugOnly<bool> ok = aEndpoint.Bind(this);
  80   MOZ_ASSERT(ok);
  81 }