RetroArch/uwp/std_filesystem_compat.h

67 lines
2.4 KiB
C++

//this file checks in order to ensure that right version of std::filesystem is returned for the version of c++
// We haven't checked which filesystem to include yet
#ifndef INCLUDE_STD_FILESYSTEM_EXPERIMENTAL
// Check for feature test macro for <filesystem>
# if defined(__cpp_lib_filesystem)
# define INCLUDE_STD_FILESYSTEM_EXPERIMENTAL 0
// Check for feature test macro for <experimental/filesystem>
# elif defined(__cpp_lib_experimental_filesystem)
# define INCLUDE_STD_FILESYSTEM_EXPERIMENTAL 1
// We can't check if headers exist...
// Let's assume experimental to be safe
# elif !defined(__has_include)
# define INCLUDE_STD_FILESYSTEM_EXPERIMENTAL 1
// Check if the header "<filesystem>" exists
# elif __has_include(<filesystem>)
// If we're compiling on Visual Studio and are not compiling with C++17, we need to use experimental
# ifdef _MSC_VER
// Check and include header that defines "_HAS_CXX17"
# if __has_include(<yvals_core.h>)
# include <yvals_core.h>
// Check for enabled C++17 support
# if defined(_HAS_CXX17) && _HAS_CXX17
// We're using C++17, so let's use the normal version
# define INCLUDE_STD_FILESYSTEM_EXPERIMENTAL 0
# endif
# endif
// If the marco isn't defined yet, that means any of the other VS specific checks failed, so we need to use experimental
# ifndef INCLUDE_STD_FILESYSTEM_EXPERIMENTAL
# define INCLUDE_STD_FILESYSTEM_EXPERIMENTAL 1
# endif
// Not on Visual Studio. Let's use the normal version
# else // #ifdef _MSC_VER
# define INCLUDE_STD_FILESYSTEM_EXPERIMENTAL 0
# endif
// Check if the header "<filesystem>" exists
# elif __has_include(<experimental/filesystem>)
# define INCLUDE_STD_FILESYSTEM_EXPERIMENTAL 1
// Fail if neither header is available with a nice error message
# else
# error Could not find system header "<filesystem>" or "<experimental/filesystem>"
# endif
// We priously determined that we need the exprimental version
# if INCLUDE_STD_FILESYSTEM_EXPERIMENTAL
// Include it
# include <experimental/filesystem>
// We need the alias from std::experimental::filesystem to std::filesystem
namespace std {
namespace filesystem = experimental::filesystem;
}
# else // We have a decent compiler and can use the normal version
# include <filesystem>// Include it
# endif
#endif // #ifndef INCLUDE_STD_FILESYSTEM_EXPERIMENTAL