1 //===-- runtime/environment.h -----------------------------------*- C++ -*-===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 #ifndef FORTRAN_RUNTIME_ENVIRONMENT_H_
10 #define FORTRAN_RUNTIME_ENVIRONMENT_H_
11 
12 #include "flang/Decimal/decimal.h"
13 #include <optional>
14 
15 namespace Fortran::runtime {
16 
17 class Terminator;
18 
19 #if FLANG_BIG_ENDIAN
20 constexpr bool isHostLittleEndian{false};
21 #elif FLANG_LITTLE_ENDIAN
22 constexpr bool isHostLittleEndian{true};
23 #else
24 #error host endianness is not known
25 #endif
26 
27 // External unformatted I/O data conversions
28 enum class Convert { Unknown, Native, LittleEndian, BigEndian, Swap };
29 
30 std::optional<Convert> GetConvertFromString(const char *, std::size_t);
31 
32 struct ExecutionEnvironment {
ExecutionEnvironmentExecutionEnvironment33   constexpr ExecutionEnvironment(){};
34   void Configure(int argc, const char *argv[], const char *envp[]);
35   const char *GetEnv(
36       const char *name, std::size_t name_length, const Terminator &terminator);
37 
38   int argc{0};
39   const char **argv{nullptr};
40   const char **envp{nullptr};
41 
42   int listDirectedOutputLineLengthLimit{79}; // FORT_FMT_RECL
43   enum decimal::FortranRounding defaultOutputRoundingMode{
44       decimal::FortranRounding::RoundNearest}; // RP(==PN)
45   Convert conversion{Convert::Unknown}; // FORT_CONVERT
46   bool noStopMessage{false}; // NO_STOP_MESSAGE=1 inhibits "Fortran STOP"
47   bool defaultUTF8{false}; // DEFAULT_UTF8
48 };
49 
50 extern ExecutionEnvironment executionEnvironment;
51 } // namespace Fortran::runtime
52 
53 #endif // FORTRAN_RUNTIME_ENVIRONMENT_H_
54