1 files changed, 101 insertions, 0 deletions
diff --git a/ipc/mscom/ActivationContext.h b/ipc/mscom/ActivationContext.h
new file mode 100644
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+++ b/ipc/mscom/ActivationContext.h
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+/* -*- 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_ActivationContext_h
+#define mozilla_mscom_ActivationContext_h
+
+#include <utility>
+
+#include "mozilla/Attributes.h"
+#include "mozilla/mscom/ActCtxResource.h"
+
+#if defined(MOZILLA_INTERNAL_API)
+#  include "mozilla/ResultVariant.h"
+#  include "nsString.h"
+#endif  // defined(MOZILLA_INTERNAL_API)
+
+#include <windows.h>
+
+namespace mozilla {
+namespace mscom {
+
+class ActivationContext final {
+ public:
+  // This is the default resource ID that the Windows dynamic linker searches
+  // for when seeking a manifest while loading a DLL.
+  static constexpr WORD kDllManifestDefaultResourceId = 2;
+
+  ActivationContext() : mActCtx(INVALID_HANDLE_VALUE) {}
+
+  explicit ActivationContext(ActCtxResource aResource);
+  explicit ActivationContext(HMODULE aLoadFromModule,
+                             WORD aResourceId = kDllManifestDefaultResourceId);
+
+  ActivationContext(ActivationContext&& aOther);
+  ActivationContext& operator=(ActivationContext&& aOther);
+
+  ActivationContext(const ActivationContext& aOther);
+  ActivationContext& operator=(const ActivationContext& aOther);
+
+  ~ActivationContext();
+
+  explicit operator bool() const { return mActCtx != INVALID_HANDLE_VALUE; }
+
+#if defined(MOZILLA_INTERNAL_API)
+  static Result<uintptr_t, HRESULT> GetCurrent();
+  static HRESULT GetCurrentManifestPath(nsAString& aOutManifestPath);
+#endif  // defined(MOZILLA_INTERNAL_API)
+
+ private:
+  void Init(ACTCTXW& aActCtx);
+  void AddRef();
+  void Release();
+
+ private:
+  HANDLE mActCtx;
+
+  friend class ActivationContextRegion;
+};
+
+class MOZ_NON_TEMPORARY_CLASS ActivationContextRegion final {
+ public:
+  template <typename... Args>
+  explicit ActivationContextRegion(Args&&... aArgs)
+      : mActCtx(std::forward<Args>(aArgs)...), mActCookie(0) {
+    Activate();
+  }
+
+  ActivationContextRegion();
+
+  explicit ActivationContextRegion(const ActivationContext& aActCtx);
+  ActivationContextRegion& operator=(const ActivationContext& aActCtx);
+
+  explicit ActivationContextRegion(ActivationContext&& aActCtx);
+  ActivationContextRegion& operator=(ActivationContext&& aActCtx);
+
+  ActivationContextRegion(ActivationContextRegion&& aRgn);
+  ActivationContextRegion& operator=(ActivationContextRegion&& aRgn);
+
+  ~ActivationContextRegion();
+
+  explicit operator bool() const { return !!mActCookie; }
+
+  ActivationContextRegion(const ActivationContextRegion&) = delete;
+  ActivationContextRegion& operator=(const ActivationContextRegion&) = delete;
+
+  bool Deactivate();
+
+ private:
+  void Activate();
+
+  ActivationContext mActCtx;
+  ULONG_PTR mActCookie;
+};
+
+}  // namespace mscom
+}  // namespace mozilla
+
+#endif  // mozilla_mscom_ActivationContext_h