Clang Preprocessor for Clang 3.2

clang_preprocessor.cpp

#include <string>
#include <iostream>

#include "llvm/Config/config.h"

#include "llvm/ADT/IntrusiveRefCntPtr.h"
#include "clang/Basic/Diagnostic.h"
#include "clang/Basic/TargetOptions.h"
#include "clang/Basic/TargetInfo.h"
#include "clang/Basic/SourceManager.h"
#include "clang/Basic/FileManager.h"

#include "clang/Lex/HeaderSearch.h"
#include "clang/Lex/Preprocessor.h"

#include "clang/Frontend/TextDiagnosticPrinter.h"
#include "clang/Frontend/TextDiagnosticBuffer.h"
#include "clang/Frontend/CompilerInstance.h"

using namespace std;
using namespace clang;


struct PPContext {
    // Takes ownership of client.
    PPContext(clang::TargetOptions& targetOpts)
  : diagID(new clang::DiagnosticIDs),
	  diagBuffer(new clang::TextDiagnosticBuffer),
	  diagEngine(diagID, diagBuffer),
	  target(clang::TargetInfo::CreateTargetInfo(diagEngine, targetOpts)),
	  fm(fsOpts),
	  sm(diagEngine, fm),
	  headers(fm, diagEngine, opts, target),
	  pp(diagEngine, opts, target, sm, headers, compilerInstance)
	{
	    // Configure warnings to be similar to what command-line `clang` outputs
	    // (see tut03).
	    // XXX: move warning initialization to libDriver
	    using namespace clang;
	    // diags.setDiagnosticMapping(diag::warn_pp_undef_identifier,diag::MAP_IGNORE);
	}

    ~PPContext()
	{
	    delete target;
	}

    llvm::IntrusiveRefCntPtr<clang::DiagnosticIDs> diagID;
    clang::TextDiagnosticBuffer *diagBuffer;
    clang::DiagnosticsEngine diagEngine;
    clang::CompilerInstance compilerInstance;
    clang::LangOptions opts;
    clang::TargetInfo* target;
    clang::FileSystemOptions fsOpts;
    clang::FileManager fm;
    clang::SourceManager sm;
    clang::HeaderSearch headers;
    clang::Preprocessor pp;
};


int main(int argc, char *argv[])
{
    if (argc != 2) {
        cerr << "No filename given" << endl;
        return EXIT_FAILURE;
    }

    clang::TargetOptions targetOpts;
    targetOpts.Triple = LLVM_DEFAULT_TARGET_TRIPLE;
    PPContext context(targetOpts);

    // Add input file
    const FileEntry* File = context.fm.getFile(argv[1]);
    if (!File) {
        cerr << "Failed to open \'" << argv[1] << "\'";
        return EXIT_FAILURE;
    }
    context.sm.createMainFileID(File);
    context.pp.EnterMainSourceFile();
    
    // Parse it
    Token Tok;
    do {
    	context.pp.Lex(Tok);
    	if (context.diagEngine.hasErrorOccurred())
    	    break;
    	context.pp.DumpToken(Tok);
    	cerr << endl;
    } while (Tok.isNot(tok::eof));

    return 0;
}