What's the easiest way to parse C++ for code generation?

Question

I would like to generate some wrapper code based on C++ types. I basically would like to parse some C++ headers, get the types, classes and their fields defined in the headers, and generate some code based on them.

What would be the easiest way to parse C++ and get type information? I thought about using the Clang C++ parser, but I couldn't make a working hello world in a couple of hours, so I gave up for the time being.
Could you advise any other way to parse C++, or if Clang is the easiest solution, could you point me to a simple getting started guide to be able to parse C++ types with it?

(basically any technology would be ok, C++, Java, C#, etc., this would be part of a command line tool)

Answer 1

Clang is definitely the easiest option. Consider using cindex python bindings, it's pretty straightforward. Alternatively, you could get an older version of clang which still features an xml backend.

EDIT: the link above seems to be down, so here is a link to the google cache of it.

Another link suggested in the comments: http://www.altdevblogaday.com/2014/03/05/implementing-a-code-generator-with-libclang/

Answer 2

Unless your object is to verify correctness, or the code involves advanced template stuff, consider using the XML output of DOxygen or GCC_XML. Alternatively, consider clang, even if that's what you found too complex. Note that for clang it might be best to work in *nix-land.

Answer 3

If your generation tool is in Java, consider using the parser from the Eclipse CDT. my set of dependencies are:

• com.ibm.icu_4.4.2.v20110823.jar
• org.eclipse.cdt.core_5.3.2.201202111925.jar
• org.eclipse.equinox.common_3.6.0.v20110523.jar

(these are from an old Eclipse version, because I have a dependency on old java class versions), but taking from the latest CDT wil do.

parsing involves:

FileContent reader;
reader = FileContent.createForExternalFileLocation(fullPath);
IScannerInfo info = new ScannerInfo(definedSymbols, includePaths);
return GPPLanguage.getDefault().getASTTranslationUnit(reader, info, FilesProvider.getInstance(), null, 0,log);

This returns an IASTTranslationUnit that can be accessed through a Visitor pattern (ASTVisitor).

I cannot comment on the accuracy of the parsing in corner scenarios, because so far I've been generating code based on simple C++ structure definitions.