//===-- Fuzzer.cpp - Fuzz the pseudoparser --------------------------------===//

//

// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.

// See https://llvm.org/LICENSE.txt for license information.

// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception

//

//===----------------------------------------------------------------------===//

#include "clang-pseudo/DirectiveTree.h"

#include "clang-pseudo/Forest.h"

#include "clang-pseudo/GLR.h"

#include "clang-pseudo/Token.h"

#include "clang-pseudo/cli/CLI.h"

#include "clang-pseudo/grammar/Grammar.h"

#include "clang-pseudo/grammar/LRTable.h"

#include "clang/Basic/LangOptions.h"

#include "llvm/ADT/StringRef.h"

#include "llvm/Support/MemoryBuffer.h"

#include "llvm/Support/raw_ostream.h"

#include <algorithm>

namespace clang {

namespace pseudo {

namespace {

class Fuzzer {

  clang::LangOptions LangOpts = clang::pseudo::genericLangOpts();

  bool Print;

public:

  Fuzzer(bool Print) : Print(Print) {}

  void operator()(llvm::StringRef Code) {

    std::string CodeStr = Code.str(); // Must be null-terminated.

    auto RawStream = lex(CodeStr, LangOpts);

    auto DirectiveStructure = DirectiveTree::parse(RawStream);

    clang::pseudo::chooseConditionalBranches(DirectiveStructure, RawStream);

    // FIXME: strip preprocessor directives

    auto ParseableStream =

        clang::pseudo::stripComments(cook(RawStream, LangOpts));

    clang::pseudo::ForestArena Arena;

    clang::pseudo::GSS GSS;

    const Language &Lang = getLanguageFromFlags();

    auto &Root =

        glrParse(clang::pseudo::ParseParams{ParseableStream, Arena, GSS},

                 *Lang.G.findNonterminal("translation-unit"), Lang);

    if (Print)

      llvm::outs() << Root.dumpRecursive(Lang.G);

  }

};

Fuzzer *Fuzz = nullptr;

} // namespace

} // namespace pseudo

} // namespace clang

extern "C" {

// Set up the fuzzer from command line flags:

//  -print                     - used for testing the fuzzer

int LLVMFuzzerInitialize(int *Argc, char ***Argv) {

  bool PrintForest = false;

  auto ConsumeArg = [&](llvm::StringRef Arg) -> bool {

    if (Arg == "-print") {

      PrintForest = true;

      return true;

    }

    return false;

  };

  *Argc = std::remove_if(*Argv + 1, *Argv + *Argc, ConsumeArg) - *Argv;

  clang::pseudo::Fuzz = new clang::pseudo::Fuzzer(PrintForest);

  return 0;

}

int LLVMFuzzerTestOneInput(uint8_t *Data, size_t Size) {

  (*clang::pseudo::Fuzz)(llvm::StringRef(reinterpret_cast<char *>(Data), Size));

  return 0;

}

}