dom/cache/StreamControl.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_cache_StreamControl_h
   8 #define mozilla_dom_cache_StreamControl_h
   9
  10 #include "mozilla/dom/cache/ReadStream.h"
  11 #include "mozilla/dom/cache/Types.h"
  12 #include "mozilla/RefPtr.h"
  13 #include "nsTObserverArray.h"
  14
  15 struct nsID;
  16
  17 namespace mozilla::dom::cache {
  18
  19 class CacheReadStream;
  20
  21 // Abstract class to help implement the stream control Child and Parent actors.
  22 // This provides an interface to partly help with serialization of IPC types,
  23 // but also an implementation for tracking ReadStream objects.
  24 class StreamControl {
  25  public:
  26   // abstract interface that must be implemented by child class
  27   virtual void SerializeControl(CacheReadStream* aReadStreamOut) = 0;
  28
  29   virtual void SerializeStream(CacheReadStream* aReadStreamOut,
  30                                nsIInputStream* aStream) = 0;
  31
  32   virtual void OpenStream(const nsID& aId, InputStreamResolver&& aResolver) = 0;
  33
  34   // inherited implementation of the ReadStream::Controllable list
  35
  36   // Begin controlling the given ReadStream.  This causes a strong ref to
  37   // be held by the control.  The ReadStream must call NoteClosed() or
  38   // ForgetReadStream() to release this ref.
  39   void AddReadStream(SafeRefPtr<ReadStream::Controllable> aReadStream);
  40
  41   // Forget the ReadStream without notifying the actor.
  42   void ForgetReadStream(SafeRefPtr<ReadStream::Controllable> aReadStream);
  43
  44   // Forget the ReadStream and then notify the actor the stream is closed.
  45   void NoteClosed(SafeRefPtr<ReadStream::Controllable> aReadStream,
  46                   const nsID& aId);
  47
  48  protected:
  49   ~StreamControl();
  50
  51   void CloseAllReadStreams();
  52
  53   void CloseAllReadStreamsWithoutReporting();
  54
  55   bool HasEverBeenRead() const;
  56
  57   // protected parts of the abstract interface
  58   virtual void NoteClosedAfterForget(const nsID& aId) = 0;
  59
  60 #ifdef DEBUG
  61   virtual void AssertOwningThread() = 0;
  62 #else
  63   void AssertOwningThread() {}
  64 #endif
  65
  66  private:
  67   // Hold strong references to ReadStream object.  When the stream is closed
  68   // it should call NoteClosed() or ForgetReadStream() to release this ref.
  69   using ReadStreamList = nsTObserverArray<SafeRefPtr<ReadStream::Controllable>>;
  70   ReadStreamList mReadStreamList;
  71 };
  72
  73 }  // namespace mozilla::dom::cache
  74
  75 #endif  // mozilla_dom_cache_StreamControl_h