Add ItemStack key-value meta storage

build/android/jni/Android.mk

@@ -164,6 +164,7 @@ LOCAL_SRC_FILES := \
 		jni/src/inventory.cpp                     \
 		jni/src/inventorymanager.cpp              \
 		jni/src/itemdef.cpp                       \
+		jni/src/itemstackmetadata.cpp             \
 		jni/src/keycode.cpp                       \
 		jni/src/light.cpp                         \
 		jni/src/localplayer.cpp                   \
@@ -305,6 +306,7 @@ LOCAL_SRC_FILES += \
 		jni/src/script/lua_api/l_env.cpp          \
 		jni/src/script/lua_api/l_inventory.cpp    \
 		jni/src/script/lua_api/l_item.cpp         \
+		jni/src/script/lua_api/l_itemstackmeta.cpp\
 		jni/src/script/lua_api/l_mainmenu.cpp     \
 		jni/src/script/lua_api/l_mapgen.cpp       \
 		jni/src/script/lua_api/l_metadata.cpp     \

doc/lua_api.txt

@@ -1411,7 +1411,7 @@ the entity itself.
 * `direction` is a unit vector, pointing from the source of the punch to
    the punched object.
 * `damage` damage that will be done to entity
-Return value of this function will determin if damage is done by this function 
+Return value of this function will determin if damage is done by this function
 (retval true) or shall be done by engine (retval false)
 
 To punch an entity/object in Lua, call:
@@ -1427,9 +1427,9 @@ Node Metadata
 -------------
 The instance of a node in the world normally only contains the three values
 mentioned in "Nodes". However, it is possible to insert extra data into a
-node. It is called "node metadata"; See "`NodeMetaRef`".
+node. It is called "node metadata"; See `NodeMetaRef`.
 
-Metadata contains two things:
+Node metadata contains two things:
 
 * A key-value store
 * An inventory
@@ -1467,6 +1467,18 @@ Example stuff:
         }
     })
 
+Item Metadata
+-------------
+Item stacks can store metadata too. See `ItemStackMetaRef`.
+
+Item metadata only contains a key-value store.
+
+Example stuff:
+
+    local meta = stack:get_meta()
+    meta:set_string("key", "value")
+    print(dump(meta:to_table()))
+
 Formspec
 --------
 Formspec defines a menu. Currently not much else than inventories are
@@ -2774,9 +2786,8 @@ These functions return the leftover itemstack.
 Class reference
 ---------------
 
-### `NodeMetaRef`
-Node metadata: reference extra data and functionality stored in a node.
-Can be gotten via `minetest.get_meta(pos)`.
+### `MetaDataRef`
+See `NodeMetaRef` and `ItemStackMetaRef`.
 
 #### Methods
 * `set_string(name, value)`
@@ -2785,13 +2796,29 @@ Can be gotten via `minetest.get_meta(pos)`.
 * `get_int(name)`
 * `set_float(name, value)`
 * `get_float(name)`
-* `get_inventory()`: returns `InvRef`
-* `to_table()`: returns `nil` or `{fields = {...}, inventory = {list1 = {}, ...}}`
+* `to_table()`: returns `nil` or a table with keys:
+    * `fields`: key-value storage
+    * `inventory`: `{list1 = {}, ...}}` (NodeMetaRef only)
 * `from_table(nil or {})`
     * Any non-table value will clear the metadata
-    * See "Node Metadata"
+    * See "Node Metadata" for an example
     * returns `true` on success
 
+### `NodeMetaRef`
+Node metadata: reference extra data and functionality stored in a node.
+Can be gotten via `minetest.get_meta(pos)`.
+
+#### Methods
+* All methods in MetaDataRef
+* `get_inventory()`: returns `InvRef`
+
+### `ItemStackMetaRef`
+ItemStack metadata: reference extra data and functionality stored in a stack.
+Can be gotten via `item:get_meta()`.
+
+#### Methods
+* All methods in MetaDataRef
+
 ### `NodeTimerRef`
 Node Timers: a high resolution persistent per-node timer.
 Can be gotten via `minetest.get_node_timer(pos)`.

src/CMakeLists.txt

@@ -415,6 +415,7 @@ set(common_SRCS
 	inventory.cpp
 	inventorymanager.cpp
 	itemdef.cpp
+	itemstackmetadata.cpp
 	light.cpp
 	log.cpp
 	map.cpp

src/content_cao.cpp

@@ -938,7 +938,7 @@ void GenericCAO::addToScene(scene::ISceneManager *smgr,
 		if(m_prop.textures.size() >= 1){
 			infostream<<"textures[0]: "<<m_prop.textures[0]<<std::endl;
 			IItemDefManager *idef = m_client->idef();
-			ItemStack item(m_prop.textures[0], 1, 0, "", idef);
+			ItemStack item(m_prop.textures[0], 1, 0, idef);
 
 			m_wield_meshnode = new WieldMeshSceneNode(
 					smgr->getRootSceneNode(), smgr, -1);

src/craftdef.cpp

@@ -139,7 +139,7 @@ static std::vector<ItemStack> craftGetItems(
 	for (std::vector<std::string>::size_type i = 0;
 			i < items.size(); i++) {
 		result.push_back(ItemStack(std::string(items[i]), (u16)1,
-			(u16)0, "", gamedef->getItemDefManager()));
+			(u16)0, gamedef->getItemDefManager()));
 	}
 	return result;
 }
@@ -1126,4 +1126,3 @@ IWritableCraftDefManager* createCraftDefManager()
 {
 	return new CCraftDefManager();
 }
-

src/inventory.cpp

@@ -45,82 +45,16 @@ static content_t content_translate_from_19_to_internal(content_t c_from)
 	return c_from;
 }
 
-// If the string contains spaces, quotes or control characters, encodes as JSON.
-// Else returns the string unmodified.
-static std::string serializeJsonStringIfNeeded(const std::string &s)
-{
-	for(size_t i = 0; i < s.size(); ++i)
-	{
-		if(s[i] <= 0x1f || s[i] >= 0x7f || s[i] == ' ' || s[i] == '\"')
-			return serializeJsonString(s);
-	}
-	return s;
-}
-
-// Parses a string serialized by serializeJsonStringIfNeeded.
-static std::string deSerializeJsonStringIfNeeded(std::istream &is)
-{
-	std::ostringstream tmp_os;
-	bool expect_initial_quote = true;
-	bool is_json = false;
-	bool was_backslash = false;
-	for(;;)
-	{
-		char c = is.get();
-		if(is.eof())
-			break;
-		if(expect_initial_quote && c == '"')
-		{
-			tmp_os << c;
-			is_json = true;
-		}
-		else if(is_json)
-		{
-			tmp_os << c;
-			if(was_backslash)
-				was_backslash = false;
-			else if(c == '\\')
-				was_backslash = true;
-			else if(c == '"')
-				break; // Found end of string
-		}
-		else
-		{
-			if(c == ' ')
-			{
-				// Found end of word
-				is.unget();
-				break;
-			}
-			else
-			{
-				tmp_os << c;
-			}
-		}
-		expect_initial_quote = false;
-	}
-	if(is_json)
-	{
-		std::istringstream tmp_is(tmp_os.str(), std::ios::binary);
-		return deSerializeJsonString(tmp_is);
-	}
-	else
-		return tmp_os.str();
-}
-
-
-ItemStack::ItemStack(std::string name_, u16 count_,
-		u16 wear_, std::string metadata_,
-		IItemDefManager *itemdef)
+ItemStack::ItemStack(const std::string &name_, u16 count_,
+		u16 wear_, IItemDefManager *itemdef)
 {
 	name = itemdef->getAlias(name_);
 	count = count_;
 	wear = wear_;
-	metadata = metadata_;
 
-	if(name.empty() || count == 0)
+	if (name.empty() || count == 0)
 		clear();
-	else if(itemdef->get(name).type == ITEM_TOOL)
+	else if (itemdef->get(name).type == ITEM_TOOL)
 		count = 1;
 }
 
@@ -137,16 +71,18 @@ void ItemStack::serialize(std::ostream &os) const
 		parts = 2;
 	if(wear != 0)
 		parts = 3;
-	if(metadata != "")
+	if (!metadata.empty())
 		parts = 4;
 
 	os<<serializeJsonStringIfNeeded(name);
 	if(parts >= 2)
 		os<<" "<<count;
 	if(parts >= 3)
 		os<<" "<<wear;
-	if(parts >= 4)
-		os<<" "<<serializeJsonStringIfNeeded(metadata);
+	if (parts >= 4) {
+		os << " ";
+		metadata.serialize(os);
+	}
 }
 
 void ItemStack::deSerialize(std::istream &is, IItemDefManager *itemdef)
@@ -289,7 +225,7 @@ void ItemStack::deSerialize(std::istream &is, IItemDefManager *itemdef)
 				wear = stoi(wear_str);
 
 			// Read metadata
-			metadata = deSerializeJsonStringIfNeeded(is);
+			metadata.deSerialize(is);
 
 			// In case fields are added after metadata, skip space here:
 			//std::getline(is, tmp, ' ');
@@ -335,7 +271,7 @@ ItemStack ItemStack::addItem(const ItemStack &newitem_,
 		*this = newitem;
 		newitem.clear();
 	}
-	// If item name or metadata differs, bail out 
+	// If item name or metadata differs, bail out
 	else if (name != newitem.name
 		|| metadata != newitem.metadata)
 	{
@@ -375,7 +311,7 @@ bool ItemStack::itemFits(const ItemStack &newitem_,
 	{
 		newitem.clear();
 	}
-	// If item name or metadata differs, bail out 
+	// If item name or metadata differs, bail out
 	else if (name != newitem.name
 		|| metadata != newitem.metadata)
 	{

src/inventory.h

@@ -23,6 +23,7 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 #include "debug.h"
 #include "itemdef.h"
 #include "irrlichttypes.h"
+#include "itemstackmetadata.h"
 #include <istream>
 #include <ostream>
 #include <string>
@@ -32,10 +33,10 @@ struct ToolCapabilities;
 
 struct ItemStack
 {
-	ItemStack(): name(""), count(0), wear(0), metadata("") {}
-	ItemStack(std::string name_, u16 count_,
-			u16 wear, std::string metadata_,
-			IItemDefManager *itemdef);
+	ItemStack(): name(""), count(0), wear(0) {}
+	ItemStack(const std::string &name_, u16 count_,
+			u16 wear, IItemDefManager *itemdef);
+
 	~ItemStack() {}
 
 	// Serialization
@@ -61,7 +62,7 @@ struct ItemStack
 		name = "";
 		count = 0;
 		wear = 0;
-		metadata = "";
+		metadata.clear();
 	}
 
 	void add(u16 n)
@@ -166,7 +167,7 @@ struct ItemStack
 	std::string name;
 	u16 count;
 	u16 wear;
-	std::string metadata;
+	ItemStackMetadata metadata;
 };
 
 class InventoryList
@@ -313,4 +314,3 @@ class Inventory
 };
 
 #endif
-

src/itemstackmetadata.cpp

@@ -0,0 +1,43 @@
+#include "itemstackmetadata.h"
+#include "util/serialize.h"
+#include "util/strfnd.h"
+
+#define DESERIALIZE_START '\x01'
+#define DESERIALIZE_KV_DELIM '\x02'
+#define DESERIALIZE_PAIR_DELIM '\x03'
+#define DESERIALIZE_START_STR "\x01"
+#define DESERIALIZE_KV_DELIM_STR "\x02"
+#define DESERIALIZE_PAIR_DELIM_STR "\x03"
+
+void ItemStackMetadata::serialize(std::ostream &os) const
+{
+	std::ostringstream os2;
+	os2 << DESERIALIZE_START;
+	for (StringMap::const_iterator
+			it = m_stringvars.begin();
+			it != m_stringvars.end(); ++it) {
+		os2 << it->first << DESERIALIZE_KV_DELIM
+		    << it->second << DESERIALIZE_PAIR_DELIM;
+	}
+	os << serializeJsonStringIfNeeded(os2.str());
+}
+
+void ItemStackMetadata::deSerialize(std::istream &is)
+{
+	std::string in = deSerializeJsonStringIfNeeded(is);
+
+	m_stringvars.clear();
+
+	if (!in.empty() && in[0] == DESERIALIZE_START) {
+		Strfnd fnd(in);
+		fnd.to(1);
+		while (!fnd.at_end()) {
+			std::string name = fnd.next(DESERIALIZE_KV_DELIM_STR);
+			std::string var  = fnd.next(DESERIALIZE_PAIR_DELIM_STR);
+			m_stringvars[name] = var;
+		}
+	} else {
+		// BACKWARDS COMPATIBILITY
+		m_stringvars[""] = in;
+	}
+}

src/itemstackmetadata.h

@@ -0,0 +1,35 @@
+/*
+Minetest
+Copyright (C) 2010-2013 rubenwardy <rubenwardy@gmail.com>
+
+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 ITEMSTACKMETADATA_HEADER
+#define ITEMSTACKMETADATA_HEADER
+
+#include "metadata.h"
+
+class Inventory;
+class IItemDefManager;
+
+class ItemStackMetadata : public Metadata
+{
+public:
+	void serialize(std::ostream &os) const;
+	void deSerialize(std::istream &is);
+};
+
+#endif