1 files changed, 37 insertions, 0 deletions
diff --git a/ipc/mscom/VTableBuilder.h b/ipc/mscom/VTableBuilder.h
new file mode 100644
index 0000000000..765ec51b0b
--- /dev/null
+++ b/ipc/mscom/VTableBuilder.h
@@ -0,0 +1,37 @@
+/* -*- 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_VTableBuilder_h
+#define mozilla_mscom_VTableBuilder_h
+
+#include <stdint.h>
+#include <unknwn.h>
+
+#if defined(__cplusplus)
+extern "C" {
+#endif
+
+/**
+ * This function constructs an interface with |aVtblSize| entries, where the
+ * IUnknown methods are valid and redirect to |aUnk|. Other than the IUnknown
+ * methods, the resulting interface is not intended to actually be called; the
+ * remaining vtable entries are null pointers to enforce that.
+ *
+ * @param aUnk The IUnknown to which the null vtable will redirect its IUnknown
+ *             methods.
+ * @param aVtblSize The total size of the vtable, including the IUnknown
+ *                  entries (thus this parameter must be >= 3).
+ * @return The resulting IUnknown, or nullptr on error.
+ */
+IUnknown* BuildNullVTable(IUnknown* aUnk, uint32_t aVtblSize);
+
+void DeleteNullVTable(IUnknown* aUnk);
+
+#if defined(__cplusplus)
+}
+#endif
+
+#endif  //  mozilla_mscom_VTableBuilder_h