VFS - Ported from old LW code

include/ebcl/VFS.hh

@@ -0,0 +1,150 @@
+/******************************************************************************/
+/* VIRTUAL FILE SYSTEM ********************************************************/
+/******************************************************************************/
+
+#ifndef _H_EBCL_VFS
+#define _H_EBCL_VFS
+
+#include <ebcl/Sets.hh>
+#include <ebcl/Strings.hh>
+#include <ebcl/Streams.hh>
+#include <ebcl/Files.hh>
+#include <ebcl/Registration.hh>
+namespace ebcl {
+
+
+/*= DRIVERS ==================================================================*/
+
+class A_VFSDriver
+{
+   public:
+	virtual ~A_VFSDriver( ) = 0;
+
+	/*
+	 * Initialisation and shutdown methods, called by the main VFS code.
+	 * These do nothing by default.
+	 */
+	virtual bool init( );
+	virtual void shutdown( );
+
+	/*
+	 * Note: the main VFS code will NEVER pass anything but an absolute
+	 * path to the methods below.
+	 */
+
+	/* Get the type of an entry in the VFS */
+	virtual E_FSEntryType typeOf( T_FSPath const& path ) = 0;
+
+	/* Checks that a path exists */
+	bool exists( T_FSPath const& path );
+
+	/* List entries matching a VFS path. The method should return true if
+	 * the path was found by the driver and was a directory, or false if
+	 * it wasn't.
+	 */
+	virtual bool list( T_FSPath const& path ,
+			T_Set< T_FSPath >& values ) = 0;
+
+	/* Try reading from a VFS file. Returns an owning pointer that's either
+	 * null if the path in question couldn't be found (or wasn't a file)
+	 * or that refers to some unspecified input stream.
+	 */
+	virtual OP_InputStream read( T_FSPath const& path ) = 0;
+
+	/* Try opening a path as an actual file. If the driver doesn't support
+	 * this, or if it cannot open the file for whatever reason, this should
+	 * return null (which is what the default implementation does).
+	 */
+	virtual OP_File file( T_FSPath const& path );
+};
+M_ABSTRACT_POINTERS( VFSDriver );
+
+
+/*= VFS FILESYSTEM DRIVER ====================================================*/
+
+/* A driver that allows the VFS to access a part of the actual filesystem. */
+class T_VFSFilesystemDriver : public A_VFSDriver
+{
+   private:
+	T_FSPath root_;
+
+   public:
+	T_VFSFilesystemDriver( ) = delete;
+	T_VFSFilesystemDriver( T_VFSFilesystemDriver const& ) = delete;
+	T_VFSFilesystemDriver( T_VFSFilesystemDriver&& ) noexcept = delete;
+
+	explicit T_VFSFilesystemDriver( T_FSPath const& root );
+
+	T_FSPath const& root( ) const;
+
+	// ---------------------------------------------------------------------
+
+	bool init( ) override;
+
+	// ---------------------------------------------------------------------
+
+	E_FSEntryType typeOf( T_FSPath const& path ) override;
+	bool list( T_FSPath const& path , T_Set< T_FSPath >& values ) override;
+
+	OP_InputStream read( T_FSPath const& path ) override;
+	OP_File file( T_FSPath const& path ) override;
+
+	// ---------------------------------------------------------------------
+
+   protected:
+	T_String getFullPath( T_FSPath const& path ) const;
+	T_Buffer< char > getOSPath( T_FSPath const& path ) const;
+};
+M_CLASS_POINTERS( VFSFilesystemDriver );
+
+
+/*= VFS CORE =================================================================*/
+
+class X_VFSInitialisationFailure : public std::runtime_error
+{
+    public:
+	X_VFSInitialisationFailure( );
+};
+
+class T_VFS : public A_PrivateImplementation
+{
+   public:
+	// Initialise the VFS, using the specified RW directory
+	T_VFS( T_FSPath const& userDir );
+
+	T_VFS( ) = delete;
+	T_VFS( T_VFS const& ) = delete;
+	T_VFS( T_VFS&& ) = delete;
+
+	// Add a new VFS driver
+	T_RegisteredItem addDriver( OP_VFSDriver&& driver );
+	template<
+		typename DriverType ,
+		typename... ArgTypes
+		>
+	T_RegisteredItem addDriver( ArgTypes&& ... arguments );
+
+	// Read-only access methods.
+	E_FSEntryType typeOf( T_FSPath const& path ) const;
+	bool list( T_FSPath const& path , T_Array< T_FSPath >& output ) const;
+	OP_InputStream read( T_FSPath const& path ) const;
+	OP_File file( T_FSPath const& path ) const;
+
+	// Read/write access for the user directory.
+	OP_File file( T_FSPath const& path , E_FileMode mode ) const;
+	OP_OutputStream write( T_FSPath const& path ) const;
+	bool mkdir( T_FSPath const& path ) const;
+	bool rmdir( T_FSPath const& path ) const;
+	bool rm( T_FSPath const& path ) const;
+	bool move( T_FSPath const& from ,
+			T_FSPath const& to ) const;
+
+	// Path style for the VFS
+	static constexpr T_FSPathStyle Style( ) noexcept;
+};
+M_CLASS_POINTERS( VFS );
+
+
+} // namespace
+#endif // _H_EBCL_VFS
+#include <ebcl/inline/VFS.hh>

include/ebcl/inline/VFS.hh

@@ -0,0 +1,60 @@
+/******************************************************************************/
+/* VIRTUAL FILE SYSTEM - INLINE CODE ******************************************/
+/******************************************************************************/
+
+#ifndef _H_EBCL_INLINE_VFS
+#define _H_EBCL_INLINE_VFS
+#include <ebcl/VFS.hh>
+namespace ebcl {
+
+
+/*= A_VFSDriver ==============================================================*/
+
+inline A_VFSDriver::~A_VFSDriver( )
+{ }
+
+inline bool A_VFSDriver::exists( T_FSPath const& path )
+{
+	const auto et( typeOf( path ) );
+	return et != E_FSEntryType::NONE;
+}
+
+
+/*= T_VFSFilesystemDriver ====================================================*/
+
+inline T_FSPath const& T_VFSFilesystemDriver::root( ) const
+{
+	return root_;
+}
+
+
+/*= X_VFSInitialisationFailure ===============================================*/
+
+inline X_VFSInitialisationFailure::X_VFSInitialisationFailure( )
+	: std::runtime_error( "unable to initialise VFS" )
+{ }
+
+
+/*= T_VFS ====================================================================*/
+
+template<
+	typename DriverType ,
+	typename... ArgTypes
+	>
+inline T_RegisteredItem T_VFS::addDriver( ArgTypes&& ... arguments )
+{
+	return addDriver( NewOwned< DriverType >(
+				std::forward< ArgTypes >( arguments ) ... ) );
+}
+
+inline constexpr T_FSPathStyle T_VFS::Style( ) noexcept
+{
+	return T_FSPathStyle{ true , false ,
+		T_Flags< E_FSPathSeparator >{
+			E_FSPathSeparator::SLASH ,
+			E_FSPathSeparator::BACKSLASH } };
+}
+
+
+}
+#endif // _H_EBCL_INLINE_VFS