llvm-project/flang/runtime/environment.h

//===-- runtime/environment.h -----------------------------------*- C++ -*-===//
//
// 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
//
//===----------------------------------------------------------------------===//

#ifndef FORTRAN_RUNTIME_ENVIRONMENT_H_
#define FORTRAN_RUNTIME_ENVIRONMENT_H_

#include "flang/Decimal/decimal.h"
#include <optional>

namespace Fortran::runtime {

#if __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
constexpr bool isHostLittleEndian{false};
#elif __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
constexpr bool isHostLittleEndian{true};
#else
#error host endianness is not known
#endif

// External unformatted I/O data conversions
enum class Convert { Unknown, Native, LittleEndian, BigEndian, Swap };

std::optional<Convert> GetConvertFromString(const char *, std::size_t);

struct ExecutionEnvironment {
  void Configure(int argc, const char *argv[], const char *envp[]);

  int argc;
  const char **argv;
  const char **envp;
  int listDirectedOutputLineLengthLimit;
  enum decimal::FortranRounding defaultOutputRoundingMode;
  Convert conversion;
};
extern ExecutionEnvironment executionEnvironment;
} // namespace Fortran::runtime

#endif // FORTRAN_RUNTIME_ENVIRONMENT_H_