gfx/ipc/FileHandleWrapper.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 _include_gfx_ipc_FileHandleWrapper_h__
   8 #define _include_gfx_ipc_FileHandleWrapper_h__
   9
  10 #include "mozilla/UniquePtrExtensions.h"
  11 #include "nsISupportsImpl.h"
  12
  13 namespace mozilla {
  14
  15 namespace ipc {
  16 template <typename T>
  17 struct IPDLParamTraits;
  18 }  // namespace ipc
  19
  20 namespace gfx {
  21
  22 //
  23 // A class for sharing file handle or shared handle among multiple clients.
  24 //
  25 // The file handles or the shared handles consume system resources. The class
  26 // could reduce the number of shared handles in a process.
  27 //
  28 class FileHandleWrapper {
  29   friend struct mozilla::ipc::IPDLParamTraits<gfx::FileHandleWrapper*>;
  30
  31  public:
  32   NS_INLINE_DECL_THREADSAFE_REFCOUNTING(FileHandleWrapper);
  33
  34   explicit FileHandleWrapper(mozilla::UniqueFileHandle&& aHandle);
  35
  36   mozilla::detail::FileHandleType GetHandle();
  37
  38   mozilla::UniqueFileHandle ClonePlatformHandle();
  39
  40  protected:
  41   ~FileHandleWrapper();
  42
  43   const mozilla::UniqueFileHandle mHandle;
  44 };
  45
  46 struct FenceInfo {
  47   FenceInfo() = default;
  48   FenceInfo(FileHandleWrapper* aFenceHandle, uint64_t aFenceValue)
  49       : mFenceHandle(aFenceHandle), mFenceValue(aFenceValue) {}
  50
  51   bool operator==(const FenceInfo& aOther) const {
  52     return mFenceHandle == aOther.mFenceHandle &&
  53            mFenceValue == aOther.mFenceValue;
  54   }
  55
  56   RefPtr<FileHandleWrapper> mFenceHandle;
  57   uint64_t mFenceValue = 0;
  58 };
  59
  60 }  // namespace gfx
  61 }  // namespace mozilla
  62
  63 #endif  // _include_gfx_ipc_FileHandleWrapper_h__