dom/ipc/SharedMessageBody.h

   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 #ifndef mozilla_dom_SharedMessageBody_h
   8 #define mozilla_dom_SharedMessageBody_h
   9
  10 #include "mozilla/dom/ipc/StructuredCloneData.h"
  11 #include "mozilla/Maybe.h"
  12
  13 namespace mozilla {
  14
  15 namespace ipc {
  16 class PBackgroundChild;
  17 }
  18
  19 namespace dom {
  20
  21 class MessagePort;
  22 class RefMessageBody;
  23 class RefMessageBodyService;
  24
  25 class SharedMessageBody final {
  26  public:
  27   NS_INLINE_DECL_REFCOUNTING(SharedMessageBody)
  28
  29   SharedMessageBody(
  30       StructuredCloneHolder::TransferringSupport aSupportsTransferring,
  31       const Maybe<nsID>& aAgentClusterId);
  32
  33   // Note that the populated MessageData borrows the underlying
  34   // JSStructuredCloneData from the SharedMessageBody, so the caller is
  35   // required to ensure that the MessageData instances are destroyed prior to
  36   // the SharedMessageBody instances.
  37   static void FromSharedToMessageChild(
  38       mozilla::ipc::PBackgroundChild* aBackgroundManager,
  39       SharedMessageBody* aData, MessageData& aMessage);
  40   static void FromSharedToMessagesChild(
  41       mozilla::ipc::PBackgroundChild* aBackgroundManager,
  42       const nsTArray<RefPtr<SharedMessageBody>>& aData,
  43       nsTArray<MessageData>& aArray);
  44
  45   // Const MessageData.
  46   static already_AddRefed<SharedMessageBody> FromMessageToSharedChild(
  47       MessageData& aMessage,
  48       StructuredCloneHolder::TransferringSupport aSupportsTransferring =
  49           StructuredCloneHolder::TransferringSupported);
  50   // Non-const MessageData.
  51   static already_AddRefed<SharedMessageBody> FromMessageToSharedChild(
  52       const MessageData& aMessage,
  53       StructuredCloneHolder::TransferringSupport aSupportsTransferring =
  54           StructuredCloneHolder::TransferringSupported);
  55   // Array of MessageData objects
  56   static bool FromMessagesToSharedChild(
  57       nsTArray<MessageData>& aArray,
  58       FallibleTArray<RefPtr<SharedMessageBody>>& aData,
  59       StructuredCloneHolder::TransferringSupport aSupportsTransferring =
  60           StructuredCloneHolder::TransferringSupported);
  61
  62   // Note that the populated MessageData borrows the underlying
  63   // JSStructuredCloneData from the SharedMessageBody, so the caller is
  64   // required to ensure that the MessageData instances are destroyed prior to
  65   // the SharedMessageBody instances.
  66   static bool FromSharedToMessagesParent(
  67       mozilla::ipc::PBackgroundParent* aManager,
  68       const nsTArray<RefPtr<SharedMessageBody>>& aData,
  69       nsTArray<MessageData>& aArray);
  70
  71   static already_AddRefed<SharedMessageBody> FromMessageToSharedParent(
  72       MessageData& aMessage,
  73       StructuredCloneHolder::TransferringSupport aSupportsTransferring =
  74           StructuredCloneHolder::TransferringSupported);
  75   static bool FromMessagesToSharedParent(
  76       nsTArray<MessageData>& aArray,
  77       FallibleTArray<RefPtr<SharedMessageBody>>& aData,
  78       StructuredCloneHolder::TransferringSupport aSupportsTransferring =
  79           StructuredCloneHolder::TransferringSupported);
  80
  81   enum ReadMethod {
  82     StealRefMessageBody,
  83     KeepRefMessageBody,
  84   };
  85
  86   void Read(JSContext* aCx, JS::MutableHandle<JS::Value> aValue,
  87             RefMessageBodyService* aRefMessageBodyService,
  88             ReadMethod aReadMethod, ErrorResult& aRv);
  89
  90   void Write(JSContext* aCx, JS::Handle<JS::Value> aValue,
  91              JS::Handle<JS::Value> aTransfers, nsID& aPortID,
  92              RefMessageBodyService* aRefMessageBodyService, ErrorResult& aRv);
  93
  94   bool TakeTransferredPortsAsSequence(
  95       Sequence<OwningNonNull<mozilla::dom::MessagePort>>& aPorts);
  96
  97  private:
  98   ~SharedMessageBody() = default;
  99
 100   UniquePtr<ipc::StructuredCloneData> mCloneData;
 101
 102   RefPtr<RefMessageBody> mRefData;
 103   Maybe<nsID> mRefDataId;
 104
 105   const StructuredCloneHolder::TransferringSupport mSupportsTransferring;
 106   const Maybe<nsID> mAgentClusterId;
 107 };
 108
 109 }  // namespace dom
 110 }  // namespace mozilla
 111
 112 #endif  // mozilla_dom_SharedMessageBody_h