FileSys: add SDMCWriteOnlyArchive

src/core/file_sys/archive_sdmcwriteonly.h

@@ -0,0 +1,57 @@
+// Copyright 2016 Citra Emulator Project
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#pragma once
+
+#include "core/file_sys/archive_sdmc.h"
+
+////////////////////////////////////////////////////////////////////////////////////////////////////
+// FileSys namespace
+
+namespace FileSys {
+
+/**
+ * Archive backend for SDMC write-only archive.
+ * The behaviour of SDMCWriteOnlyArchive is almost the same as SDMCArchive, except for
+ *  - OpenDirectory is unsupported;
+ *  - OpenFile with read flag is unsupported.
+ */
+class SDMCWriteOnlyArchive : public SDMCArchive {
+public:
+    SDMCWriteOnlyArchive(const std::string& mount_point) : SDMCArchive(mount_point) {}
+
+    std::string GetName() const override {
+        return "SDMCWriteOnlyArchive: " + mount_point;
+    }
+
+    ResultVal<std::unique_ptr<FileBackend>> OpenFile(const Path& path,
+                                                     const Mode& mode) const override;
+
+    ResultVal<std::unique_ptr<DirectoryBackend>> OpenDirectory(const Path& path) const override;
+};
+
+/// File system interface to the SDMC write-only archive
+class ArchiveFactory_SDMCWriteOnly final : public ArchiveFactory {
+public:
+    ArchiveFactory_SDMCWriteOnly(const std::string& mount_point);
+
+    /**
+     * Initialize the archive.
+     * @return true if it initialized successfully
+     */
+    bool Initialize();
+
+    std::string GetName() const override {
+        return "SDMCWriteOnly";
+    }
+
+    ResultVal<std::unique_ptr<ArchiveBackend>> Open(const Path& path) override;
+    ResultCode Format(const Path& path, const FileSys::ArchiveFormatInfo& format_info) override;
+    ResultVal<ArchiveFormatInfo> GetFormatInfo(const Path& path) const override;
+
+private:
+    std::string sdmc_directory;
+};
+
+} // namespace FileSys