/* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying

   file LICENSE.rst or https://cmake.org/licensing for details.  */

/*

 * Fuzzer for CMake's Fortran dependency scanner

 *

 * CMake runs a flex lexer and a bison parser over Fortran sources to discover

 * module dependencies: MODULE, SUBMODULE, USE and INCLUDE statements, plus the

 * preprocessor directives that guard them. This fuzzer drives that scanner.

 */

#include <cstddef>

#include <cstdint>

#include <cstdio>

#include <set>

#include <string>

#include <vector>

#include <unistd.h>

#include "cmFortranParser.h"

#include "cmSystemTools.h"

static constexpr size_t kMaxInputSize = 256 * 1024;

static std::string g_testDir;

extern "C" int LLVMFuzzerInitialize(int* argc, char*** argv)

{

  (void)argc;

  (void)argv;

  char tmpl[] = "/tmp/cmake_fuzz_fortran_XXXXXX";

  char* dir = mkdtemp(tmpl);

  if (dir) {

    g_testDir = dir;

  } else {

    g_testDir = "/tmp/cmake_fuzz_fortran";

    cmSystemTools::MakeDirectory(g_testDir);

  }

  return 0;

}

extern "C" int LLVMFuzzerTestOneInput(uint8_t const* data, size_t size)

{

  if (size == 0 || size > kMaxInputSize) {

    return 0;

  }

  std::string const source = g_testDir + "/test.f90";

  {

    FILE* fp = fopen(source.c_str(), "wb");

    if (!fp) {

      return 0;

    }

    fwrite(data, 1, size, fp);

    fclose(fp);

  }

  cmFortranCompiler compiler;

  compiler.Id = "GNU";

  compiler.SModSep = "@";

  compiler.SModExt = ".smod";

  cmFortranSourceInfo info;

  info.Source = source;

  std::vector<std::string> const includes;

  std::set<std::string> const defines;

  cmFortranParser parser(compiler, includes, defines, info);

  if (cmFortranParser_FilePush(&parser, source.c_str())) {

    cmFortran_yyparse(parser.Scanner);

  }

  unlink(source.c_str());

  return 0;

}