Add ModMetadata API (#5131)

* mod can create a ModMetadata object where store its values and retrieve it.
* Modmetadata object can only be fetched at mod loading
* Save when modified using same time as map interval or at server stop
* add helper function to get mod storage path
* ModMetadata has exactly same calls than all every other Metadata

1 files changed, 62 insertions, 0 deletions

diff --git a/src/script/lua_api/l_storage.h b/src/script/lua_api/l_storage.h
new file mode 100644
index 000000000..fde2828ad
--- /dev/null
+++ b/src/script/lua_api/l_storage.h
@@ -0,0 +1,62 @@
+/*
+Minetest
+Copyright (C) 2013 celeron55, Perttu Ahola <celeron55@gmail.com>
+Copyright (C) 2017 nerzhul, Loic Blot <loic.blot@unix-experience.fr>
+
+This program is free software; you can redistribute it and/or modify
+it under the terms of the GNU Lesser General Public License as published by
+the Free Software Foundation; either version 2.1 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU Lesser General Public License for more details.
+
+You should have received a copy of the GNU Lesser General Public License along
+with this program; if not, write to the Free Software Foundation, Inc.,
+51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+*/
+
+#ifndef __L_STORAGE_H__
+#define __L_STORAGE_H__
+
+#include "lua_api/l_base.h"
+#include "l_metadata.h"
+
+class ModMetadata;
+
+class ModApiStorage: public ModApiBase
+{
+protected:
+	static int l_get_mod_storage(lua_State *L);
+public:
+	static void Initialize(lua_State *L, int top);
+
+};
+
+class StorageRef: public MetaDataRef
+{
+private:
+	ModMetadata *m_object;
+
+	static const char className[];
+	static const luaL_reg methods[];
+
+	virtual Metadata* getmeta(bool auto_create);
+	virtual void clearMeta();
+
+	// garbage collector
+	static int gc_object(lua_State *L);
+public:
+	StorageRef(ModMetadata *object);
+	~StorageRef() {}
+
+	static void Register(lua_State *L);
+	static void create(lua_State *L, ModMetadata *object);
+
+	static StorageRef *checkobject(lua_State *L, int narg);
+	static ModMetadata* getobject(StorageRef *ref);
+};
+
+#endif /* __L_STORAGE_H__ */