filesystem/include/ghc/fs_std_impl.hpp
Chris Sauer aaaf381d9d Improvements to preprocessor conditions for falling back to std::filesystem
- Supports more Apple platforms, including future ones, which will always support std::filesystem, like with visionOS
- Simplifies cases.  Undefined preprocessor values are guaranteed to default evaluate to 0
- Moves <Availability.h> include inside conditional, avoiding the include where not needed.
- Removes reference to wchar for std headers on windows, which seemed to be out of date, since the define it might have been referring to was commented
- (And some other small things.)
2023-07-26 21:26:33 -07:00

61 lines
3.5 KiB
C++

//---------------------------------------------------------------------------------------
//
// ghc::filesystem - A C++17-like filesystem implementation for C++11/C++14
//
//---------------------------------------------------------------------------------------
//
// Copyright (c) 2018, Steffen Schümann <s.schuemann@pobox.com>
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in all
// copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
// SOFTWARE.
//
//---------------------------------------------------------------------------------------
// fs_std_impl.hpp - The implementation header for the header/implementation seperated usage of
// ghc::filesystem that does nothing if std::filesystem is detected.
// This file can be used to hide the implementation of ghc::filesystem into a single cpp.
// The cpp has to include this before including fs_std_fwd.hpp directly or via a different
// header to work.
//---------------------------------------------------------------------------------------
#if _MSVC_LANG >= 201703L || __cplusplus >= 201703L && defined(__has_include)
// ^ Supports MSVC prior to 15.7 without setting /Zc:__cplusplus to fix __cplusplus
// _MSVC_LANG works regardless. But without the switch, the compiler always reported 199711L: https://blogs.msdn.microsoft.com/vcblog/2018/04/09/msvc-now-correctly-reports-__cplusplus/
#if __has_include(<filesystem>) // Two stage __has_include needed for MSVC 2015 and per https://gcc.gnu.org/onlinedocs/cpp/_005f_005fhas_005finclude.html
#define GHC_USE_STD_FS
// Old Apple OSs don't support std::filesystem, though the header is available at compile
// time. In particular, std::filesystem is unavailable before macOS 10.15, iOS/tvOS 13.0,
// and watchOS 6.0.
#ifdef __APPLE__
#include <Availability.h>
// Note: This intentionally uses std::filesystem on any new Apple OS, like visionOS
// released after std::filesystem, where std::filesystem is always available.
// (All other __<platform>_VERSION_MIN_REQUIREDs will be undefined and thus 0.)
#if __MAC_OS_X_VERSION_MIN_REQUIRED && __MAC_OS_X_VERSION_MIN_REQUIRED < 101500 \
|| __IPHONE_OS_VERSION_MIN_REQUIRED && __IPHONE_OS_VERSION_MIN_REQUIRED < 130000 \
|| __TV_OS_VERSION_MIN_REQUIRED && __TV_OS_VERSION_MIN_REQUIRED < 130000 \
|| __WATCH_OS_VERSION_MAX_ALLOWED && __WATCH_OS_VERSION_MAX_ALLOWED < 60000
#undef GHC_USE_STD_FS
#endif
#endif
#endif
#endif
#ifndef GHC_USE_STD_FS
#include <ghc/fs_impl.hpp>
#endif