获取COM对象的DLL文件，而不使用CLSID和注册表在c ++ [英] Get the DLL-file for a COM-Object without using CLSID and registry in c++

问题描述

可以在不使用CLSID和注册表查找的情况下获取加载的COM对象的DLL文件名吗？

Is it possible to get the DLL-filename for a loaded COM-Object without using the CLSID and a registry lookup?

我有一个 IUnknown 或在我的情况下一个 IBaseFilter 接口指针，现在我想获得创建此COM对象的DLL文件名。我可以使用对象点地址来反向查找已创建模块的已加载模块吗？然后在 GetModuleFileName 中使用 HMODULE 。

I have an IUnknown or in my case an IBaseFilter interface pointer and now I want to get the DLL-filename who created this COM-Object. Can I use the object point adress to reverse lookup the loaded module where it was created? And then get the HMODULE to use it in GetModuleFileName.

推荐答案

自然只使用一些黑客。对象本身在堆上，是共享的，但你可以看到它的虚拟表的位置 - 它应该几乎普遍在创建者的二进制文件的只读数据部分。

Only using some hacks, naturally. The object itself is on the heap, which is shared, but you could see where the its virtual table resides - it should be almost universally in the read-only data section of the creator's binary.

因此，在对象中加载第一个指针，因为虚拟表指针驻留在Windows COM ABI中：

So load the first pointer in the object, as that's where virtual table pointers reside in Windows COM ABI:

IBaseFilter* pFilter = ...;
char* vtbl = *reinterpret_cast<char**>(pFilter);

然后我最初建议用 EnumProcessModules c $ c> like eg 此处，调用 GetModuleInformation（ ），并检查 vtbl 指针是否落入其内存范围。愚蠢的我，我忘了 VirtualQueryEx（），所以更好地做罗马描述在他的答案。

Then I originally suggested to do some circus with EnumProcessModules() like e.g. here, call GetModuleInformation() on each module and check if the vtbl pointer falls into its memory ranges. Stupid me, I forgot about VirtualQueryEx(), so better do it as Roman described in his answer.

当然，所有这些都只能用于进程中的COM对象，并且没有涉及到的代理。我认为它仍然可以在你的DirectShow案例中有用。

Of course, all this can work only for in-process COM objects and where there are no proxies involved. I assume it can still be useful in your DirectShow case though.

还可以看到关于使用 IPersist :: GetClassId $ c>和注册表查找，它应该适用于大多数DirectShow过滤器。

Also see the comment about using IPersist::GetClassId() and registry lookup, it should apply nicely to most DirectShow filters.

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