Reimplementation of FunctionStub, to avoid rewriting potentially executing co...

chrome_frame/vtable_patch_manager.h

 // Copyright (c) 2009 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CHROME_FRAME_VTABLE_PATCH_MANAGER_H_
 #define CHROME_FRAME_VTABLE_PATCH_MANAGER_H_
 
 #include <windows.h>
 
 #include <list>
 
 #include "base/lock.h"
 
 struct FunctionStub;
+
 // This namespace provides methods to patch VTable methods of COM interfaces.
 namespace vtable_patch {
 
+// Internal implementation, exposed only for testing.
+namespace internal {
+
+// Replaces *entry with new_proc iff *entry is curr_proc.
+// Returns true iff *entry was rewritten.
+// Note: does not crash on access violation.
+bool ReplaceFunctionPointer(void** entry, void* new_proc, void* curr_proc);
+
+}  // namespace internal
+
 // This structure represents information about one VTable method.
 // We allocate an array of these structures per VTable that we patch to
 // remember the original method. We also use this structure to actually
 // describe the VTable patch functions
 struct MethodPatchInfo {
   int index_;
   PROC method_;
   FunctionStub* stub_;
 };
 
@@ skipping 81 matching lines @@
 #define IS_PATCHED(IFName) \
   (IFName##_PatchInfo[0].stub_ != NULL)
 
 // Ends the declaration of a VTable patch by adding an entry with
 // index set to -1.
 #define END_VTABLE_PATCHES() \
       -1, NULL, NULL \
     };
 
 #endif  // CHROME_FRAME_VTABLE_PATCH_MANAGER_H_