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include/platform/filesystem/data_store.h

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+/* -----------------------------------------------------------------------------
+	GSFramework
+	Copyright 2001-2013 Emmanuel Julien. All Rights Reserved.
+----------------------------------------------------------------------------- */
+
+
+#ifndef	__NIODATASTORE__
+#define	__NIODATASTORE__
+
+
+		#include "filesystem/io_handle.h"
+		#include "container/nlist.h"
+		#include "nstring/nstring.h"
+		#include "thread/mutex.h"
+		#include "unit/nunit.h"
+
+
+namespace GS {
+	namespace IO {
+
+/*!
+	@short Data store.
+*/
+class	DataStore
+{
+		Threading::Mutex mutex;
+
+		SharedPtr <Base> io;
+		size_t		limit;
+
+		uint		id_seed;
+		String		GetNewId();
+
+public:
+
+	struct	Entry
+	{
+		String		id;
+		size_t		size;
+		String		user;
+
+		Entry() : size(0) {}
+	};
+
+private:
+
+		AutoList <Entry *> entries;
+
+		Entry		*GetEntry(const String &id) const;
+
+public:
+
+		Base		*GetIO() const { return io.c_ptr(); }
+
+		const AutoList <Entry *> &GetEntries() const { return entries; }
+
+		/// Reserve space on the store, an empty id is returned if the store is full.
+virtual	String		Reserve(size_t size);
+		/// Free a store alias.
+virtual	bool		Free(const String &id);
+
+		/// Store data on a reserved id.
+		bool		Store(const String &id, const void *data, size_t size, const char *user_data = 0);
+
+		/// Get entry size.
+		size_t		GetEntrySize(const String &id) const;
+
+		/// Get the current store size.
+		size_t		GetStoreSize() const;
+		/// Get the store free space size.
+		size_t		GetFreeStore() const;
+
+		/// Restore store content from the storage fs.
+		bool		Load(const char *path = "store.db");
+		/// Save store content to the storage fs.
+		bool		Save(const char *path = "store.db");
+
+		DataStore(Base *storage, size_t storage_limit = Units::MB(32)) : io(storage), limit(storage_limit), id_seed(0) {}
+};
+
+	}	// IO
+}	// GS
+
+
+#endif	// __NIODATASTORE__