Virtual Filesystem (#597)

* Add VfsFile and VfsDirectory classes

* Finish abstract Vfs classes

* Implement RealVfsFile (computer fs backend)

* Finish RealVfsFile and RealVfsDirectory

* Finished OffsetVfsFile

* More changes

* Fix import paths

* Major refactor

* Remove double const

* Use experimental/filesystem or filesystem depending on compiler

* Port partition_filesystem

* More changes

* More Overhaul

* FSP_SRV fixes

* Fixes and testing

* Try to get filesystem to compile

* Filesystem on linux

* Remove std::filesystem and document/test

* Compile fixes

* Missing include

* Bug fixes

* Fixes

* Rename v_file and v_dir

* clang-format fix

* Rename NGLOG_* to LOG_*

* Most review changes

* Fix TODO

* Guess 'main' to be Directory by filename

1 files changed, 65 insertions, 0 deletions

diff --git a/src/core/file_sys/vfs_real.h b/src/core/file_sys/vfs_real.h
new file mode 100644
index 000000000..01717f485
--- /dev/null
+++ b/src/core/file_sys/vfs_real.h
@@ -0,0 +1,65 @@
+// Copyright 2018 yuzu emulator team
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#pragma once
+
+#include "common/file_util.h"
+#include "core/file_sys/filesystem.h"
+#include "core/file_sys/vfs.h"
+
+namespace FileSys {
+
+// An implmentation of VfsFile that represents a file on the user's computer.
+struct RealVfsFile : public VfsFile {
+    RealVfsFile(const std::string& name, Mode perms = Mode::Read);
+
+    std::string GetName() const override;
+    size_t GetSize() const override;
+    bool Resize(size_t new_size) override;
+    std::shared_ptr<VfsDirectory> GetContainingDirectory() const override;
+    bool IsWritable() const override;
+    bool IsReadable() const override;
+    size_t Read(u8* data, size_t length, size_t offset) const override;
+    size_t Write(const u8* data, size_t length, size_t offset) override;
+    bool Rename(const std::string& name) override;
+
+private:
+    FileUtil::IOFile backing;
+    std::string path;
+    std::string parent_path;
+    std::vector<std::string> path_components;
+    std::vector<std::string> parent_components;
+    Mode perms;
+};
+
+// An implementation of VfsDirectory that represents a directory on the user's computer.
+struct RealVfsDirectory : public VfsDirectory {
+    RealVfsDirectory(const std::string& path, Mode perms);
+
+    std::vector<std::shared_ptr<VfsFile>> GetFiles() const override;
+    std::vector<std::shared_ptr<VfsDirectory>> GetSubdirectories() const override;
+    bool IsWritable() const override;
+    bool IsReadable() const override;
+    std::string GetName() const override;
+    std::shared_ptr<VfsDirectory> GetParentDirectory() const override;
+    std::shared_ptr<VfsDirectory> CreateSubdirectory(const std::string& name) override;
+    std::shared_ptr<VfsFile> CreateFile(const std::string& name) override;
+    bool DeleteSubdirectory(const std::string& name) override;
+    bool DeleteFile(const std::string& name) override;
+    bool Rename(const std::string& name) override;
+
+protected:
+    bool ReplaceFileWithSubdirectory(VirtualFile file, VirtualDir dir) override;
+
+private:
+    std::string path;
+    std::string parent_path;
+    std::vector<std::string> path_components;
+    std::vector<std::string> parent_components;
+    Mode perms;
+    std::vector<std::shared_ptr<VfsFile>> files;
+    std::vector<std::shared_ptr<VfsDirectory>> subdirectories;
+};
+
+} // namespace FileSys