How to undecorate name from decorated name?

Question

At a post of Raymond Chen, he seems to be able to know the function's undecorated name from the decorated name. I have no idea how could he do this.

In this decorated name,

?GetName@PushButton@UILibrary@@UAEPB_WPAPAVStringHolder@2@@Z

What does the each component mean?

Answer 1

To avoid guessing, and still not really use tools, the UnDecorateSymbolName function may be of use. I would hope that gives an authoritative correct answer.

To do it manually, this page has some information on the scheme, as do these.

The basic outline is _name@scope@scope@@parameters@something@@something. I suspect the last two parts are stack size and calling convention or similar, but the documentation likely has more detail.

Answer 2

Name mangling is compiler dependant.

In the article you linked, Raymond is using an MS util (undname) to remove the mangling.

Here is a table showing how common compilers mangle.

Answer 3

Microsoft Visual Studio comes with a undname.exe tool.

http://msdn.microsoft.com/en-us/library/ms937379.aspx

If you have MS VS at a default location you can use:

"C:\Program Files (x86)\Microsoft Visual Studio 10.0\VC\bin\undname.exe" ?GetName@PushButton@UILibrary@@UAEPB_WPAPAVStringHolder@2@@Z

Microsoft (R) C++ Name Undecorator Copyright (C) Microsoft Corporation. All rights reserved.

Undecoration of :- "?GetName@PushButton@UILibrary@@UAEPB_WPAPAVStringHolder@2@@Z" is :- "public: virtual wchar_t const * __thiscall UILibrary::PushButton::GetName(class UILibrary::StringHolder * *)"