Adding upstream version 86.0.1.upstream/86.0.1upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 66 insertions, 0 deletions

diff --git a/ipc/mscom/FastMarshaler.h b/ipc/mscom/FastMarshaler.h
new file mode 100644
index 0000000000..e1f3e88801
--- /dev/null
+++ b/ipc/mscom/FastMarshaler.h
@@ -0,0 +1,66 @@
+/* -*- 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/. */
+
+#ifndef mozilla_mscom_FastMarshaler_h
+#define mozilla_mscom_FastMarshaler_h
+
+#include "mozilla/Atomics.h"
+#include "mozilla/mscom/Aggregation.h"
+#include "mozilla/RefPtr.h"
+
+#include <objidl.h>
+
+namespace mozilla {
+namespace mscom {
+
+/**
+ * COM ping functionality is enabled by default and is designed to free strong
+ * references held by defunct client processes. However, this incurs a
+ * significant performance penalty in a11y code due to large numbers of remote
+ * objects being created and destroyed within a short period of time. Thus, we
+ * turn off pings to improve performance.
+ * ACHTUNG! When COM pings are disabled, Release calls from remote clients are
+ * never sent to the server! If you use this marshaler, you *must* explicitly
+ * disconnect clients using CoDisconnectObject when the object is no longer
+ * relevant. Otherwise, references to the object will never be released, causing
+ * a leak.
+ */
+class FastMarshaler final : public IMarshal {
+ public:
+  static HRESULT Create(IUnknown* aOuter, IUnknown** aOutMarshalerUnk);
+
+  // IMarshal
+  STDMETHODIMP GetUnmarshalClass(REFIID riid, void* pv, DWORD dwDestContext,
+                                 void* pvDestContext, DWORD mshlflags,
+                                 CLSID* pCid) override;
+  STDMETHODIMP GetMarshalSizeMax(REFIID riid, void* pv, DWORD dwDestContext,
+                                 void* pvDestContext, DWORD mshlflags,
+                                 DWORD* pSize) override;
+  STDMETHODIMP MarshalInterface(IStream* pStm, REFIID riid, void* pv,
+                                DWORD dwDestContext, void* pvDestContext,
+                                DWORD mshlflags) override;
+  STDMETHODIMP UnmarshalInterface(IStream* pStm, REFIID riid,
+                                  void** ppv) override;
+  STDMETHODIMP ReleaseMarshalData(IStream* pStm) override;
+  STDMETHODIMP DisconnectObject(DWORD dwReserved) override;
+
+ private:
+  FastMarshaler(IUnknown* aOuter, HRESULT* aResult);
+  ~FastMarshaler() = default;
+
+  static DWORD GetMarshalFlags(DWORD aDestContext, DWORD aMshlFlags);
+
+  Atomic<ULONG> mRefCnt;
+  IUnknown* mOuter;
+  RefPtr<IUnknown> mStdMarshalUnk;
+  IMarshal* mStdMarshalWeak;
+  DECLARE_AGGREGATABLE(FastMarshaler);
+};
+
+}  // namespace mscom
+}  // namespace mozilla
+
+#endif  // mozilla_mscom_FastMarshaler_h