code:
/*
Minetest
Copyright (C) 2013 celeron55, Perttu Ahola <celeron55@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.
*/
#include "common/c_content.h"
#include "common/c_converter.h"
#include "common/c_types.h"
#include "nodedef.h"
#include "object_properties.h"
#include "cpp_api/s_node.h"
#include "lua_api/l_object.h"
#include "lua_api/l_item.h"
#include "common/c_internal.h"
#include "server.h"
#include "log.h"
#include "tool.h"
#include "serverobject.h"
#include "porting.h"
#include "mg_schematic.h"
#include "noise.h"
#include "util/pointedthing.h"
#include "debug.h" // For FATAL_ERROR
#include <json/json.h>

struct EnumString es_TileAnimationType[] =
{
	{TAT_NONE, "none"},
	{TAT_VERTICAL_FRAMES, "vertical_frames"},
	{TAT_SHEET_2D, "sheet_2d"},
	{0, NULL},
};

/******************************************************************************/
void read_item_definition(lua_State* L, int index,
		const ItemDefinition &default_def, ItemDefinition &def)
{
	if (index < 0)
		index = lua_gettop(L) + 1 + index;

	def.type = (ItemType)getenumfield(L, index, "type",
			es_ItemType, ITEM_NONE);
	getstringfield(L, index, "name", def.name);
	getstringfield(L, index, "description", def.description);
	getstringfield(L, index, "inventory_image", def.inventory_image);
	getstringfield(L, index, "wield_image", def.wield_image);
	getstringfield(L, index, "palette", def.palette_image);

	// Read item color.
	lua_getfield(L, index, "color");
	read_color(L, -1, &def.color);
	lua_pop(L, 1);

	lua_getfield(L, index, "wield_scale");
	if(lua_istable(L, -1)){
		def.wield_scale = check_v3f(L, -1);
	}
	lua_pop(L, 1);

	int stack_max = getintfield_default(L, index, "stack_max", def.stack_max);
	def.stack_max = rangelim(stack_max, 1, U16_MAX);

	lua_getfield(L, index, "on_use");
	def.usable = lua_isfunction(L, -1);
	lua_pop(L, 1);

	getboolfield(L, index, "liquids_pointable", def.liquids_pointable);

	warn_if_field_exists(L, index, "tool_digging_properties",
			"Deprecated; use tool_capabilities");

	lua_getfield(L, index, "tool_capabilities");
	if(lua_istable(L, -1)){
		def.tool_capabilities = new ToolCapabilities(
				read_tool_capabilities(L, -1));
	}

	// If name is "" (hand), ensure there are ToolCapabilities
	// because it will be looked up there whenever any other item has
	// no ToolCapabilities
	if(def.name == "" && def.tool_capabilities == NULL){
		def.tool_capabilities = new ToolCapabilities();
	}

	lua_getfield(L, index, "groups");
	read_groups(L, -1, def.groups);
	lua_pop(L, 1);

	lua_getfield(L, index, "sounds");
	if(lua_istable(L, -1)){
		lua_getfield(L, -1, "place");
		read_soundspec(L, -1, def.sound_place);
		lua_pop(L, 1);
		lua_getfield(L, -1, "place_failed");
		read_soundspec(L, -1, def.sound_place_failed);
		lua_pop(L, 1);
	}
	lua_pop(L, 1);

	def.range = getfloatfield_default(L, index, "range", def.range);

	// Client shall immediately place this node when player places the item.
	// Server will update the precise end result a moment later.
	// "" = no prediction
	getstringfield(L, index, "node_placement_prediction",
			def.node_placement_prediction);
}

/******************************************************************************/
void push_item_definition(lua_State *L, const ItemDefinition &i)
{
	lua_newtable(L);
	lua_pushstring(L, i.name.c_str());
	lua_setfield(L, -2, "name");
	lua_pushstring(L, i.description.c_str());
	lua_setfield(L, -2, "description");
}

void push_item_definition_full(lua_State *L, const ItemDefinition &i)
{
	std::string type(es_ItemType[(int)i.type].str);

	lua_newtable(L);
	lua_pushstring(L, i.name.c_str());
	lua_setfield(L, -2, "name");
	lua_pushstring(L, i.description.c_str());
	lua_setfield(L, -2, "description");
	lua_pushstring(L, type.c_str());
	lua_setfield(L, -2, "type");
	lua_pushstring(L, i.inventory_image.c_str());
	lua_setfield(L, -2, "inventory_image");
	lua_pushstring(L, i.wield_image.c_str());
	lua_setfield(L, -2, "wield_image");
	lua_pushstring(L, i.palette_image.c_str());
	lua_setfield(L, -2, "palette_image");
	push_ARGB8(L, i.color);
	lua_setfield(L, -2, "color");
	push_v3f(L, i.wield_scale);
	lua_setfield(L, -2, "wield_scale");
	lua_pushinteger(L, i.stack_max);
	lua_setfield(L, -2, "stack_max");
	lua_pushboolean(L, i.usable);
	lua_setfield(L, -2, "usable");
	lua_pushboolean(L, i.liquids_pointable);
	lua_setfield(L, -2, "liquids_pointable");
	if (i.type == ITEM_TOOL) {
		push_tool_capabilities(L, ToolCapabilities(
			i.tool_capabilities->full_punch_interval,
			i.tool_capabilities->max_drop_level,
			i.tool_capabilities->groupcaps,
			i.tool_capabilities->damageGroups));
		lua_setfield(L, -2, "tool_capabilities");
	}
	push_groups(L, i.groups);
	lua_setfield(L, -2, "groups");
	push_soundspec(L, i.sound_place);
	lua_setfield(L, -2, "sound_place");
	push_soundspec(L, i.sound_place_failed);
	lua_setfield(L, -2, "sound_place_failed");
	lua_pushstring(L, i.node_placement_prediction.c_str());
	lua_setfield(L, -2, "node_placement_prediction");
}

/******************************************************************************/
void read_object_properties(lua_State *L, int index,
		ObjectProperties *prop, IItemDefManager *idef)
{
	if(index < 0)
		index = lua_gettop(L) + 1 + index;
	if(!lua_istable(L, index))
		return;

	prop->hp_max = getintfield_default(L, -1, "hp_max", 10);

	getboolfield(L, -1, "physical", prop->physical);
	getboolfield(L, -1, "collide_with_objects", prop->collideWithObjects);

	getfloatfield(L, -1, "weight", prop->weight);

	lua_getfield(L, -1, "collisionbox");
	if(lua_istable(L, -1))
		prop->collisionbox = read_aabb3f(L, -1, 1.0);
	lua_pop(L, 1);

	getstringfield(L, -1, "visual", prop->visual);

	getstringfield(L, -1, "mesh", prop->mesh);

	lua_getfield(L, -1, "visual_size");
	if(lua_istable(L, -1))
		prop->visual_size = read_v2f(L, -1);
	lua_pop(L, 1);

	lua_getfield(L, -1, "textures");
	if(lua_istable(L, -1)){
		prop->textures.clear();
		int table = lua_gettop(L);
		lua_pushnil(L);
		while(lua_next(L, table) != 0){
			// key at index -2 and value at index -1
			if(lua_isstring(L, -1))
				prop->textures.push_back(lua_tostring(L, -1));
			else
				prop->textures.push_back("");
			// removes value, keeps key for next iteration
			lua_pop(L, 1);
		}
	}
	lua_pop(L, 1);

	lua_getfield(L, -1, "colors");
	if (lua_istable(L, -1)) {
		int table = lua_gettop(L);
		prop->colors.clear();
		for (lua_pushnil(L); lua_next(L, table); lua_pop(L, 1)) {
			video::SColor color(255, 255, 255, 255);
			read_color(L, -1, &color);
			prop->colors.push_back(color);
		}
	}
	lua_pop(L, 1);

	lua_getfield(L, -1, "spritediv");
	if(lua_istable(L, -1))
		prop->spritediv = read_v2s16(L, -1);
	lua_pop(L, 1);

	lua_getfield(L, -1, "initial_sprite_basepos");
	if(lua_istable(L, -1))
		prop->initial_sprite_basepos = read_v2s16(L, -1);
	lua_pop(L, 1);

	getboolfield(L, -1, "is_visible", prop->is_visible);
	getboolfield(L, -1, "makes_footstep_sound", prop->makes_footstep_sound);
	getfloatfield(L, -1, "automatic_rotate", prop->automatic_rotate);
	if (getfloatfield(L, -1, "stepheight", prop->stepheight))
		prop->stepheight *= BS;
	lua_getfield(L, -1, "automatic_face_movement_dir");
	if (lua_isnumber(L, -1)) {
		prop->automatic_face_movement_dir = true;
		prop->automatic_face_movement_dir_offset = luaL_checknumber(L, -1);
	} else if (lua_isboolean(L, -1)) {
		prop->automatic_face_movement_dir = lua_toboolean(L, -1);
		prop->automatic_face_movement_dir_offset = 0.0;
	}
	lua_pop(L, 1);
	getboolfield(L, -1, "backface_culling", prop->backface_culling);

	getstringfield(L, -1, "nametag", prop->nametag);
	lua_getfield(L, -1, "nametag_color");
	if (!lua_isnil(L, -1)) {
		video::SColor color = prop->nametag_color;
		if (read_color(L, -1, &color))
			prop->nametag_color = color;
	}
	lua_pop(L, 1);

	lua_getfield(L, -1, "automatic_face_movement_max_rotation_per_sec");
	if (lua_isnumber(L, -1)) {
		prop->automatic_face_movement_max_rotation_per_sec = luaL_checknumber(L, -1);
	}
	lua_pop(L, 1);
	getstringfield(L, -1, "infotext", prop->infotext);
	lua_getfield(L, -1, "wield_item");
	if (!lua_isnil(L, -1))
		prop->wield_item = read_item(L, -1, idef).getItemString();
	lua_pop(L, 1);
}

/******************************************************************************/
void push_object_properties(lua_State *L, ObjectProperties *prop)
{
	lua_newtable(L);
	lua_pushnumber(L, prop->hp_max);
	lua_setfield(L, -2, "hp_max");
	lua_pushboolean(L, prop->physical);
	lua_setfield(L, -2, "physical");
	lua_pushboolean(L, prop->collideWithObjects);
	lua_setfield(L, -2, "collide_with_objects");
	lua_pushnumber(L, prop->weight);
	lua_setfield(L, -2, "weight");
	push_aabb3f(L, prop->collisionbox);
	lua_setfield(L, -2, "collisionbox");
	lua_pushlstring(L, prop->visual.c_str(), prop->visual.size());
	lua_setfield(L, -2, "visual");
	lua_pushlstring(L, prop->mesh.c_str(), prop->mesh.size());
	lua_setfield(L, -2, "mesh");
	push_v2f(L, prop->visual_size);
	lua_setfield(L, -2, "visual_size");

	lua_newtable(L);
	u16 i = 1;
	for (std::vector<std::string>::iterator it = prop->textures.begin();
			it != prop->textures.end(); ++it) {
		lua_pushlstring(L, it->c_str(), it->size());
		lua_rawseti(L, -2, i);
	}
	lua_setfield(L, -2, "textures");

	lua_newtable(L);
	i = 1;
	for (std::vector<video::SColor>::iterator it = prop->colors.begin();
			it != prop->colors.end(); ++it) {
		push_ARGB8(L, *it);
		lua_rawseti(L, -2, i);
	}
	lua_setfield(L, -2, "colors");

	push_v2s16(L, prop->spritediv);
	lua_setfield(L, -2, "spritediv");
	push_v2s16(L, prop->initial_sprite_basepos);
	lua_setfield(L, -2, "initial_sprite_basepos");
	lua_pushboolean(L, prop->is_visible);
	lua_setfield(L, -2, "is_visible");
	lua_pushboolean(L, prop->makes_footstep_sound);
	lua_setfield(L, -2, "makes_footstep_sound");
	lua_pushnumber(L, prop->automatic_rotate);
	lua_setfield(L, -2, "automatic_rotate");
	lua_pushnumber(L, prop->stepheight / BS);
	lua_setfield(L, -2, "stepheight");
	if (prop->automatic_face_movement_dir)
		lua_pushnumber(L, prop->automatic_face_movement_dir_offset);
	else
		lua_pushboolean(L, false);
	lua_setfield(L, -2, "automatic_face_movement_dir");
	lua_pushboolean(L, prop->backface_culling);
	lua_setfield(L, -2, "backface_culling");
	lua_pushlstring(L, prop->nametag.c_str(), prop->nametag.size());
	lua_setfield(L, -2, "nametag");
	push_ARGB8(L, prop->nametag_color);
	lua_setfield(L, -2, "nametag_color");
	lua_pushnumber(L, prop->automatic_face_movement_max_rotation_per_sec);
	lua_setfield(L, -2, "automatic_face_movement_max_rotation_per_sec");
	lua_pushlstring(L, prop->infotext.c_str(), prop->infotext.size());
	lua_setfield(L, -2, "infotext");
	lua_pushlstring(L, prop->wield_item.c_str(), prop->wield_item.size());
	lua_setfield(L, -2, "wield_item");
}

/******************************************************************************/
TileDef read_tiledef(lua_State *L, int index, u8 drawtype)
{
	if(index < 0)
		index = lua_gettop(L) + 1 + index;

	TileDef tiledef;

	bool default_tiling = true;
	bool default_culling = true;
	switch (drawtype) {
		case NDT_PLANTLIKE:
		case NDT_FIRELIKE:
			default_tiling = false;
			// "break" is omitted here intentionaly, as PLANTLIKE
			// FIRELIKE drawtype both should default to having
			// backface_culling to false.
		case NDT_MESH:
		case NDT_LIQUID:
			default_culling = false;
			break;
		default:
			break;
	}

	// key at index -2 and value at index
	if(lua_isstring(L, index)){
		// "default_lava.png"
		tiledef.name = lua_tostring(L, index);
		tiledef.tileable_vertical = default_tiling;
		tiledef.tileable_horizontal = default_tiling;
		tiledef.backface_culling = default_culling;
	}
	else if(lua_istable(L, index))
	{
		// name="default_lava.png"
		tiledef.name = "";
		getstringfield(L, index, "name", tiledef.name);
		getstringfield(L, index, "image", tiledef.name); // MaterialSpec compat.
		tiledef.backface_culling = getboolfield_default(
			L, index, "backface_culling", default_culling);
		tiledef.tileable_horizontal = getboolfield_default(
			L, index, "tileable_horizontal", default_tiling);
		tiledef.tileable_vertical = getboolfield_default(
			L, index, "tileable_vertical", default_tiling);
		// color = ...
		lua_getfield(L, index, "color");
		tiledef.has_color = read_color(L, -1, &tiledef.color);
		lua_pop(L, 1);
		// animation = {}
		lua_getfield(L, index, "animation");
		tiledef.animation = read_animation_definition(L, -1);
		lua_pop(L, 1);
	}

	return tiledef;
}

/******************************************************************************/
ContentFeatures read_content_features(lua_State *L, int index)
{
	if(index < 0)
		index = lua_gettop(L) + 1 + index;

	ContentFeatures f;

	/* Cache existence of some callbacks */
	lua_getfield(L, index, "on_construct");
	if(!lua_isnil(L, -1)) f.has_on_construct = true;
	lua_pop(L, 1);
	lua_getfield(L, index, "on_destruct");
	if(!lua_isnil(L, -1)) f.has_on_destruct = true;
	lua_pop(L, 1);
	lua_getfield(L, index, "after_destruct");
	if(!lua_isnil(L, -1)) f.has_after_destruct = true;
	lua_pop(L, 1);

	lua_getfield(L, index, "on_rightclick");
	f.rightclickable = lua_isfunction(L, -1);
	lua_pop(L, 1);

	/* Name */
	getstringfield(L, index, "name", f.name);

	/* Groups */
	lua_getfield(L, index, "groups");
	read_groups(L, -1, f.groups);
	lua_pop(L, 1);

	/* Visual definition */

	f.drawtype = (NodeDrawType)getenumfield(L, index, "drawtype",
			ScriptApiNode::es_DrawType,NDT_NORMAL);
	getfloatfield(L, index, "visual_scale", f.visual_scale);

	/* Meshnode model filename */
	getstringfield(L, index, "mesh", f.mesh);

	// tiles = {}
	lua_getfield(L, index, "tiles");
	// If nil, try the deprecated name "tile_images" instead
	if(lua_isnil(L, -1)){
		lua_pop(L, 1);
		warn_if_field_exists(L, index, "tile_images",
				"Deprecated; new name is \"tiles\".");
		lua_getfield(L, index, "tile_images");
	}
	if(lua_istable(L, -1)){
		int table = lua_gettop(L);
		lua_pushnil(L);
		int i = 0;
		while(lua_next(L, table) != 0){
			// Read tiledef from value
			f.tiledef[i] = read_tiledef(L, -1, f.drawtype);
			// removes value, keeps key for next iteration
			lua_pop(L, 1);
			i++;
			if(i==6){
				lua_pop(L, 1);
				break;
			}
		}
		// Copy last value to all remaining textures
		if(i >= 1){
			TileDef lasttile = f.tiledef[i-1];
			while(i < 6){
				f.tiledef[i] = lasttile;
				i++;
			}
		}
	}
	lua_pop(L, 1);

	// overlay_tiles = {}
	lua_getfield(L, index, "overlay_tiles");
	if (lua_istable(L, -1)) {
		int table = lua_gettop(L);
		lua_pushnil(L);
		int i = 0;
		while (lua_next(L, table) != 0) {
			// Read tiledef from value
			f.tiledef_overlay[i] = read_tiledef(L, -1, f.drawtype);
			// removes value, keeps key for next iteration
			lua_pop(L, 1);
			i++;
			if (i == 6) {
				lua_pop(L, 1);
				break;
			}
		}
		// Copy last value to all remaining textures
		if (i >= 1) {
			TileDef lasttile = f.tiledef_overlay[i - 1];
			while (i < 6) {
				f.tiledef_overlay[i] = lasttile;
				i++;
			}
		}
	}
	lua_pop(L, 1);

	// special_tiles = {}
	lua_getfield(L, index, "special_tiles");
	// If nil, try the deprecated name "special_materials" instead
	if(lua_isnil(L, -1)){
		lua_pop(L, 1);
		warn_if_field_exists(L, index, "special_materials",
				"Deprecated; new name is \"special_tiles\".");
		lua_getfield(L, index, "special_materials");
	}
	if(lua_istable(L, -1)){
		int table = lua_gettop(L);
		lua_pushnil(L);
		int i = 0;
		while(lua_next(L, table) != 0){
			// Read tiledef from value
			f.tiledef_special[i] = read_tiledef(L, -1, f.drawtype);
			// removes value, keeps key for next iteration
			lua_pop(L, 1);
			i++;
			if(i==CF_SPECIAL_COUNT){
				lua_pop(L, 1);
				break;
			}
		}
	}
	lua_pop(L, 1);

	f.alpha = getintfield_default(L, index, "alpha", 255);

	bool usealpha = getboolfield_default(L, index,
			"use_texture_alpha", false);
	if (usealpha)
		f.alpha = 0;

	// Read node color.
	lua_getfield(L, index, "color");
	read_color(L, -1, &f.color);
	lua_pop(L, 1);

	getstringfield(L, index, "palette", f.palette_name);

	/* Other stuff */

	lua_getfield(L, index, "post_effect_color");
	read_color(L, -1, &f.post_effect_color);
	lua_pop(L, 1);

	f.param_type = (ContentParamType)getenumfield(L, index, "paramtype",
			ScriptApiNode::es_ContentParamType, CPT_NONE);
	f.param_type_2 = (ContentParamType2)getenumfield(L, index, "paramtype2",
			ScriptApiNode::es_ContentParamType2, CPT2_NONE);

	if (f.palette_name != "" &&
			!(f.param_type_2 == CPT2_COLOR ||
			f.param_type_2 == CPT2_COLORED_FACEDIR ||
			f.param_type_2 == CPT2_COLORED_WALLMOUNTED))
		warningstream << "Node " << f.name.c_str()
			<< " has a palette, but not a suitable paramtype2." << std::endl;

	// Warn about some deprecated fields
	warn_if_field_exists(L, index, "wall_mounted",
			"Deprecated; use paramtype2 = 'wallmounted'");
	warn_if_field_exists(L, index, "light_propagates",
			"Deprecated; determined from paramtype");
	warn_if_field_exists(L, index, "dug_item",
			"Deprecated; use 'drop' field");
	warn_if_field_exists(L, index, "extra_dug_item",
			"Deprecated; use 'drop' field");
	warn_if_field_exists(L, index, "extra_dug_item_rarity",
			"Deprecated; use 'drop' field");
	warn_if_field_exists(L, index, "metadata_name",
			"Deprecated; use on_add and metadata callbacks");

	// True for all ground-like things like stone and mud, false for eg. trees
	getboolfield(L, index, "is_ground_content", f.is_ground_content);
	f.light_propagates = (f.param_type == CPT_LIGHT);
	getboolfield(L, index, "sunlight_propagates", f.sunlight_propagates);
	// This is used for collision detection.
	// Also for general solidness queries.
	getboolfield(L, index, "walkable", f.walkable);
	// Player can point to these
	getboolfield(L, index, "pointable", f.pointable);
	// Player can dig these
	getboolfield(L, index, "diggable", f.diggable);
	// Player can climb these
	getboolfield(L, index, "climbable", f.climbable);
	// Player can build on these
	getboolfield(L, index, "buildable_to", f.buildable_to);
	// Liquids flow into and replace node
	getboolfield(L, index, "floodable", f.floodable);
	// Whether the node is non-liquid, source liquid or flowing liquid
	f.liquid_type = (LiquidType)getenumfield(L, index, "liquidtype",
			ScriptApiNode::es_LiquidType, LIQUID_NONE);
	// If the content is liquid, this is the flowing version of the liquid.
	getstringfield(L, index, "liquid_alternative_flowing",
			f.liquid_alternative_flowing);
	// If the content is liquid, this is the source version of the liquid.
	getstringfield(L, index, "liquid_alternative_source",
			f.liquid_alternative_source);
	// Viscosity for fluid flow, ranging from 1 to 7, with
	// 1 giving almost instantaneous propagation and 7 being
	// the slowest possible
	f.liquid_viscosity = getintfield_default(L, index,
			"liquid_viscosity", f.liquid_viscosity);
	f.liquid_range = getintfield_default(L, index,
			"liquid_range", f.liquid_range);
	f.leveled = getintfield_default(L, index, "leveled", f.leveled);

	getboolfield(L, index, "liquid_renewable", f.liquid_renewable);
	f.drowning = getintfield_default(L, index,
			"drowning", f.drowning);
	// Amount of light the node emits
	f.light_source = getintfield_default(L, index,
			"light_source", f.light_source);
	if (f.light_source > LIGHT_MAX) {
		warningstream << "Node " << f.name.c_str()
			<< " had greater light_source than " << LIGHT_MAX
			<< ", it was reduced." << std::endl;
		f.light_source = LIGHT_MAX;
	}
	f.damage_per_second = getintfield_default(L, index,
			"damage_per_second", f.damage_per_second);

	lua_getfield(L, index, "node_box");
	if(lua_istable(L, -1))
		f.node_box = read_nodebox(L, -1);
	lua_pop(L, 1);

	lua_getfield(L, index, "connects_to");
	if (lua_istable(L, -1)) {
		int table = lua_gettop(L);
		lua_pushnil(L);
		while (lua_next(L, table) != 0) {
			// Value at -1
			f.connects_to.push_back(lua_tostring(L, -1));
			lua_pop(L, 1);
		}
	}
	lua_pop(L, 1);

	lua_getfield(L, index, "connect_sides");
	if (lua_istable(L, -1)) {
		int table = lua_gettop(L);
		lua_pushnil(L);
		while (lua_next(L, table) != 0) {
			// Value at -1
			std::string side(lua_tostring(L, -1));
			// Note faces are flipped to make checking easier
			if (side == "top")
				f.connect_sides |= 2;
			else if (side == "bottom")
				f.connect_sides |= 1;
			else if (side == "front")
				f.connect_sides |= 16;
			else if (side == "left")
				f.connect_sides |= 32;
			else if (side == "back")
				f.connect_sides |= 4;
			else if (side == "right")
				f.connect_sides |= 8;
			else
				warningstream << "Unknown value for \"connect_sides\": "
					<< side << std::endl;
			lua_pop(L, 1);
		}
	}
	lua_pop(L, 1);

	lua_getfield(L, index, "selection_box");
	if(lua_istable(L, -1))
		f.selection_box = read_nodebox(L, -1);
 	lua_pop(L, 1);

	lua_getfield(L, index, "collision_box");
	if(lua_istable(L, -1))
		f.collision_box = read_nodebox(L, -1);
	lua_pop(L, 1);

	f.waving = getintfield_default(L, index,
			"waving", f.waving);

	// Set to true if paramtype used to be 'facedir_simple'
	getboolfield(L, index, "legacy_facedir_simple", f.legacy_facedir_simple);
	// Set to true if wall_mounted used to be set to true
	getboolfield(L, index, "legacy_wallmounted", f.legacy_wallmounted);

	// Sound table
	lua_getfield(L, index, "sounds");
	if(lua_istable(L, -1)){
		lua_getfield(L, -1, "footstep");
		read_soundspec(L, -1, f.sound_footstep);
		lua_pop(L, 1);
		lua_getfield(L, -1, "dig");
		read_soundspec(L, -1, f.sound_dig);
		lua_pop(L, 1);
		lua_getfield(L, -1, "dug");
		read_soundspec(L, -1, f.sound_dug);
		lua_pop(L, 1);
	}
	lua_pop(L, 1);

	return f;
}

void push_content_features(lua_State *L, const ContentFeatures &c)
{
	std::string paramtype(ScriptApiNode::es_ContentParamType[(int)c.param_type].str);
	std::string paramtype2(ScriptApiNode::es_ContentParamType2[(int)c.param_type_2].str);
	std::string drawtype(ScriptApiNode::es_DrawType[(int)c.drawtype].str);
	std::string liquid_type(ScriptApiNode::es_LiquidType[(int)c.liquid_type].str);

	/* Missing "tiles" because I don't see a usecase (at least not yet). */

	lua_newtable(L);
	lua_pushboolean(L, c.has_on_construct);
	lua_setfield(L, -2, "has_on_construct");
	lua_pushboolean(L, c.has_on_destruct);
	lua_setfield(L, -2, "has_on_destruct");
	lua_pushboolean(L, c.has_after_destruct);
	lua_setfield(L, -2, "has_after_destruct");
	lua_pushstring(L, c.name.c_str());
	lua_setfield(L, -2, "name");
	push_groups(L, c.groups);
	lua_setfield(L, -2, "groups");
	lua_pushstring(L, paramtype.c_str());
	lua_setfield(L, -2, "paramtype");
	lua_pushstring(L, paramtype2.c_str());
	lua_setfield(L, -2, "paramtype2");
	lua_pushstring(L, drawtype.c_str());
	lua_setfield(L, -2, "drawtype");
	if (!c.mesh.empty()) {
		lua_pushstring(L, c.mesh.c_str());
		lua_setfield(L, -2, "mesh");
	}
#ifndef SERVER
	push_ARGB8(L, c.minimap_color);       // I know this is not set-able w/ register_node,
	lua_setfield(L, -2, "minimap_color"); // but the people need to know!
#endif
	lua_pushnumber(L, c.visual_scale);
	lua_setfield(L, -2, "visual_scale");
	lua_pushnumber(L, c.alpha);
	lua_setfield(L, -2, "alpha");
	if (!c.palette_name.empty()) {
		push_ARGB8(L, c.color);
		lua_setfield(L, -2, "color");

		lua_pushstring(L, c.palette_name.c_str());
		lua_setfield(L, -2, "palette_name");

		push_palette(L, c.palette);
		lua_setfield(L, -2, "palette");
	}
	lua_pushnumber(L, c.waving);
	lua_setfield(L, -2, "waving");
	lua_pushnumber(L, c.connect_sides);
	lua_setfield(L, -2, "connect_sides");

	lua_newtable(L);
	u16 i = 1;
	for (std::vector<std::string>::const_iterator it = c.connects_to.begin();
			it != c.connects_to.end(); ++it) {
		lua_pushlstring(L, it->c_str(), it->size());
		lua_rawseti(L, -2, i);
	}
	lua_setfield(L, -2, "connects_to");

	push_ARGB8(L, c.post_effect_color);
	lua_setfield(L, -2, "post_effect_color");
	lua_pushnumber(L, c.leveled);
	lua_setfield(L, -2, "leveled");
	lua_pushboolean(L, c.sunlight_propagates);
	lua_setfield(L, -2, "sunlight_propagates");
	lua_pushnumber(L, c.light_source);
	lua_setfield(L, -2, "light_source");
	lua_pushboolean(L, c.is_ground_content);
	lua_setfield(L, -2, "is_ground_content");
	lua_pushboolean(L, c.walkable);
	lua_setfield(L, -2, "walkable");
	lua_pushboolean(L, c.pointable);
	lua_setfield(L, -2, "pointable");
	lua_pushboolean(L, c.diggable);
	lua_setfield(L, -2, "diggable");
	lua_pushboolean(L, c.climbable);
	lua_setfield(L, -2, "climbable");
	lua_pushboolean(L, c.buildable_to);
	lua_setfield(L, -2, "buildable_to");
	lua_pushboolean(L, c.rightclickable);
	lua_setfield(L, -2, "rightclickable");
	lua_pushnumber(L, c.damage_per_second);
	lua_setfield(L, -2, "damage_per_second");
	if (c.isLiquid()) {
		lua_pushstring(L, liquid_type.c_str());
		lua_setfield(L, -2, "liquid_type");
		lua_pushstring(L, c.liquid_alternative_flowing.c_str());
		lua_setfield(L, -2, "liquid_alternative_flowing");
		lua_pushstring(L, c.liquid_alternative_source.c_str());
		lua_setfield(L, -2, "liquid_alternative_source");
		lua_pushnumber(L, c.liquid_viscosity);
		lua_setfield(L, -2, "liquid_viscosity");
		lua_pushboolean(L, c.liquid_renewable);
		lua_setfield(L, -2, "liquid_renewable");
		lua_pushnumber(L, c.liquid_range);
		lua_setfield(L, -2, "liquid_range");
	}
	lua_pushnumber(L, c.drowning);
	lua_setfield(L, -2, "drowning");
	lua_pushboolean(L, c.floodable);
	lua_setfield(L, -2, "floodable");
	push_nodebox(L, c.node_box);
	lua_setfield(L, -2, "node_box");
	push_nodebox(L, c.selection_box);
	lua_setfield(L, -2, "selection_box");
	push_nodebox(L, c.collision_box);
	lua_setfield(L, -2, "collision_box");
	lua_newtable(L);
	push_soundspec(L, c.sound_footstep);
	lua_setfield(L, -2, "sound_footstep");
	push_soundspec(L, c.sound_dig);
	lua_setfield(L, -2, "sound_dig");
	push_soundspec(L, c.sound_dug);
	lua_setfield(L, -2, "sound_dug");
	lua_setfield(L, -2, "sounds");
	lua_pushboolean(L, c.legacy_facedir_simple);
	lua_setfield(L, -2, "legacy_facedir_simple");
	lua_pushboolean(L, c.legacy_wallmounted);
	lua_setfield(L, -2, "legacy_wallmounted");
}

/******************************************************************************/
void push_nodebox(lua_State *L, const NodeBox &box)
{
	lua_newtable(L);
	switch (box.type)
	{
		case NODEBOX_REGULAR:
			lua_pushstring(L, "regular");
			lua_setfield(L, -2, "type");
			break;
		case NODEBOX_LEVELED:
		case NODEBOX_FIXED:
			lua_pushstring(L, "fixed");
			lua_setfield(L, -2, "type");
			push_box(L, box.fixed);
			lua_setfield(L, -2, "fixed");
			break;
		case NODEBOX_WALLMOUNTED:
			lua_pushstring(L, "wallmounted");
			lua_setfield(L, -2, "type");
			push_aabb3f(L, box.wall_top);
			lua_setfield(L, -2, "wall_top");
			push_aabb3f(L, box.wall_bottom);
			lua_setfield(L, -2, "wall_bottom");
			push_aabb3f(L, box.wall_side);
			lua_setfield(L, -2, "wall_side");
			break;
		case NODEBOX_CONNECTED:
			lua_pushstring(L, "connected");
			lua_setfield(L, -2, "type");
			push_box(L, box.connect_top);
			lua_setfield(L, -2, "connect_top");
			push_box(L, box.connect_bottom);
			lua_setfield(L, -2, "connect_bottom");
			push_box(L, box.connect_front);
			lua_setfield(L, -2, "connect_front");
			push_box(L, box.connect_back);
			lua_setfield(L, -2, "connect_back");
			push_box(L, box.connect_left);
			lua_setfield(L, -2, "connect_left");
			push_box(L, box.connect_right);
			lua_setfield(L, -2, "connect_right");
			break;
		default:
			FATAL_ERROR("Invalid box.type");
			break;
	}
}

void push_box(lua_State *L, const std::vector<aabb3f> &box)
{
	lua_newtable(L);
	u8 i = 1;
	for (std::vector<aabb3f>::const_iterator it = box.begin();
	                it != box.end(); ++it) {
		push_aabb3f(L, (*it));
		lua_rawseti(L, -2, i);
	}
}

/******************************************************************************/
void push_palette(lua_State *L, const std::vector<video::SColor> *palette)
{
	lua_createtable(L, palette->size(), 0);
	int newTable = lua_gettop(L);
	int index = 1;
	std::vector<video::SColor>::const_iterator iter;
	for (iter = palette->begin(); iter != palette->end(); ++iter) {
		push_ARGB8(L, (*iter));
		lua_rawseti(L, newTable, index);
		index++;
	}
}

/******************************************************************************/
void read_server_sound_params(lua_State *L, int index,
		ServerSoundParams &params)
{
	if(index < 0)
		index = lua_gettop(L) + 1 + index;
	// Clear
	params = ServerSoundParams();
	if(lua_istable(L, index)){
		getfloatfield(L, index, "gain", params.gain);
		getstringfield(L, index, "to_player", params.to_player);
		getfloatfield(L, index, "fade", params.fade);
		lua_getfield(L, index, "pos");
		if(!lua_isnil(L, -1)){
			v3f p = read_v3f(L, -1)*BS;
			params.pos = p;
			params.type = ServerSoundParams::SSP_POSITIONAL;
		}
		lua_pop(L, 1);
		lua_getfield(L, index, "object");
		if(!lua_isnil(L, -1)){
			ObjectRef *ref = ObjectRef::checkobject(L, -1);
			ServerActiveObject *sao = ObjectRef::getobject(ref);
			if(sao){
				params.object = sao->getId();
				params.type = ServerSoundParams::SSP_OBJECT;
			}
		}
		lua_pop(L, 1);
		params.max_hear_distance = BS*getfloatfield_default(L, index,
				"max_hear_distance", params.max_hear_distance/BS);
		getboolfield(L, index, "loop", params.loop);
	}
}

/******************************************************************************/
void read_soundspec(lua_State *L, int index, SimpleSoundSpec &spec)
{
	if(index < 0)
		index = lua_gettop(L) + 1 + index;
	if(lua_isnil(L, index)){
	} else if(lua_istable(L, index)){
		getstringfield(L, index, "name", spec.name);
		getfloatfield(L, index, "gain", spec.gain);
		getfloatfield(L, index, "fade", spec.fade);
	} else if(lua_isstring(L, index)){
		spec.name = lua_tostring(L, index);
	}
}

void push_soundspec(lua_State *L, const SimpleSoundSpec &spec)
{
	lua_newtable(L);
	lua_pushstring(L, spec.name.c_str());
	lua_setfield(L, -2, "name");
	lua_pushnumber(L, spec.gain);
	lua_setfield(L, -2, "gain");
	lua_pushnumber(L, spec.fade);
	lua_setfield(L, -2, "fade");
}

/******************************************************************************/
NodeBox read_nodebox(lua_State *L, int index)
{
	NodeBox nodebox;
	if(lua_istable(L, -1)){
		nodebox.type = (NodeBoxType)getenumfield(L, index, "type",
				ScriptApiNode::es_NodeBoxType, NODEBOX_REGULAR);

#define NODEBOXREAD(n, s) \
	do { \
		lua_getfield(L, index, (s)); \
		if (lua_istable(L, -1)) \
			(n) = read_aabb3f(L, -1, BS); \
		lua_pop(L, 1); \
	} while (0)

#define NODEBOXREADVEC(n, s) \
	do { \
		lua_getfield(L, index, (s)); \
		if (lua_istable(L, -1)) \
			(n) = read_aabb3f_vector(L, -1, BS); \
		lua_pop(L, 1); \
	} while (0)
		NODEBOXREADVEC(nodebox.fixed, "fixed");
		NODEBOXREAD(nodebox.wall_top, "wall_top");
		NODEBOXREAD(nodebox.wall_bottom, "wall_bottom");
		NODEBOXREAD(nodebox.wall_side, "wall_side");
		NODEBOXREADVEC(nodebox.connect_top, "connect_top");
		NODEBOXREADVEC(nodebox.connect_bottom, "connect_bottom");
		NODEBOXREADVEC(nodebox.connect_front, "connect_front");
		NODEBOXREADVEC(nodebox.connect_left, "connect_left");
		NODEBOXREADVEC(nodebox.connect_back, "connect_back");
		NODEBOXREADVEC(nodebox.connect_right, "connect_right");
	}
	return nodebox;
}

/******************************************************************************/
MapNode readnode(lua_State *L, int index, INodeDefManager *ndef)
{
	lua_getfield(L, index, "name");
	if (!lua_isstring(L, -1))
		throw LuaError("Node name is not set or is not a string!");
	const char *name = lua_tostring(L, -1);
	lua_pop(L, 1);

	u8 param1 = 0;
	lua_getfield(L, index, "param1");
	if (!lua_isnil(L, -1))
		param1 = lua_tonumber(L, -1);
	lua_pop(L, 1);

	u8 param2 = 0;
	lua_getfield(L, index, "param2");
	if (!lua_isnil(L, -1))
		param2 = lua_tonumber(L, -1);
	lua_pop(L, 1);

	return MapNode(ndef, name, param1, param2);
}

/******************************************************************************/
void pushnode(lua_State *L, const MapNode &n, INodeDefManager *ndef)
{
	lua_newtable(L);
	lua_pushstring(L, ndef->get(n).name.c_str());
	lua_setfield(L, -2, "name");
	lua_pushnumber(L, n.getParam1());
	lua_setfield(L, -2, "param1");
	lua_pushnumber(L, n.getParam2());
	lua_setfield(L, -2, "param2");
}

/******************************************************************************/
void warn_if_field_exists(lua_State *L, int table,
		const char *name, const std::string &message)
{
	lua_getfield(L, table, name);
	if (!lua_isnil(L, -1)) {
		warningstream << "Field \"" << name << "\": "
				<< message << std::endl;
		infostream << script_get_backtrace(L) << std::endl;
	}
	lua_pop(L, 1);
}

/******************************************************************************/
int getenumfield(lua_State *L, int table,
		const char *fieldname, const EnumString *spec, int default_)
{
	int result = default_;
	string_to_enum(spec, result,
			getstringfield_default(L, table, fieldname, ""));
	return result;
}

/******************************************************************************/
bool string_to_enum(const EnumString *spec, int &result,
		const std::string &str)
{
	const EnumString *esp = spec;
	while(esp->str){
		if(str == std::string(esp->str)){
			result = esp->num;
			return true;
		}
		esp++;
	}
	return false;
}

/******************************************************************************/
ItemStack read_item(lua_State* L, int index, IItemDefManager *idef)
{
	if(index < 0)
		index = lua_gettop(L) + 1 + index;

	if(lua_isnil(L, index))
	{
		return ItemStack();
	}
	else if(lua_isuserdata(L, index))
	{
		// Convert from LuaItemStack
		LuaItemStack *o = LuaItemStack::checkobject(L, index);
		return o->getItem();
	}
	else if(lua_isstring(L, index))
	{
		// Convert from itemstring
		std::string itemstring = lua_tostring(L, index);
		try
		{
			ItemStack item;
			item.deSerialize(itemstring, idef);
			return item;
		}
		catch(SerializationError &e)
		{
			warningstream<<"unable to create item from itemstring"
					<<": "<<itemstring<<std::endl;
			return ItemStack();
		}
	}
	else if(lua_istable(L, index))
	{
		// Convert from table
		std::string name = getstringfield_default(L, index, "name", "");
		int count = getintfield_default(L, index, "count", 1);
		int wear = getintfield_default(L, index, "wear", 0);

		ItemStack istack(name, count, wear, idef);

		// BACKWARDS COMPATIBLITY
		std::string value = getstringfield_default(L, index, "metadata", "");
		istack.metadata.setString("", value);

		// Get meta
		lua_getfield(L, index, "meta");
		int fieldstable = lua_gettop(L);
		if (lua_istable(L, fieldstable)) {
			lua_pushnil(L);
			while (lua_next(L, fieldstable) != 0) {
				// key at index -2 and value at index -1
				std::string key = lua_tostring(L, -2);
				size_t value_len;
				const char *value_cs = lua_tolstring(L, -1, &value_len);
				std::string value(value_cs, value_len);
				istack.metadata.setString(key, value);
				lua_pop(L, 1); // removes value, keeps key for next iteration
			}
		}

		return istack;
	} else {
		throw LuaError("Expecting itemstack, itemstring, table or nil");
	}
}

/******************************************************************************/
void push_tool_capabilities(lua_State *L,
		const ToolCapabilities &toolcap)
{
	lua_newtable(L);
	setfloatfield(L, -1, "full_punch_interval", toolcap.full_punch_interval);
		setintfield(L, -1, "max_drop_level", toolcap.max_drop_level);
		// Create groupcaps table
		lua_newtable(L);
		// For each groupcap
		for (ToolGCMap::const_iterator i = toolcap.groupcaps.begin();
			i != toolcap.groupcaps.end(); ++i) {
			// Create groupcap table
			lua_newtable(L);
			const std::string &name = i->first;
			const ToolGroupCap &groupcap = i->second;
			// Create subtable "times"
			lua_newtable(L);
			for (UNORDERED_MAP<int, float>::const_iterator
					i = groupcap.times.begin(); i != groupcap.times.end(); ++i) {
				lua_pushinteger(L, i->first);
				lua_pushnumber(L, i->second);
				lua_settable(L, -3);
			}
			// Set subtable "times"
			lua_setfield(L, -2, "times");
			// Set simple parameters
			setintfield(L, -1, "maxlevel", groupcap.maxlevel);
			setintfield(L, -1, "uses", groupcap.uses);
			// Insert groupcap table into groupcaps table
			lua_setfield(L, -2, name.c_str());
		}
		// Set groupcaps table
		lua_setfield(L, -2, "groupcaps");
		//Create damage_groups table
		lua_newtable(L);
		// For each damage group
		for (DamageGroup::const_iterator i = toolcap.damageGroups.begin();
			i != toolcap.damageGroups.end(); ++i) {
			// Create damage group table
			lua_pushinteger(L, i->second);
			lua_setfield(L, -2, i->first.c_str());
		}
		lua_setfield(L, -2, "damage_groups");
}

/******************************************************************************/
void push_inventory_list(lua_State *L, Inventory *inv, const char *name)
{
	InventoryList *invlist = inv->getList(name);
	if(invlist == NULL){
		lua_pushnil(L);
		return;
	}
	std::vector<ItemStack> items;
	for(u32 i=0; i<invlist->getSize(); i++)
		items.push_back(invlist->getItem(i));
	push_items(L, items);
}

/******************************************************************************/
void read_inventory_list(lua_State *L, int tableindex,
		Inventory *inv, const char *name, Server* srv, int forcesize)
{
	if(tableindex < 0)
		tableindex = lua_gettop(L) + 1 + tableindex;
	// If nil, delete list
	if(lua_isnil(L, tableindex)){
		inv->deleteList(name);
		return;
	}
	// Otherwise set list
	std::vector<ItemStack> items = read_items(L, tableindex,srv);
	int listsize = (forcesize != -1) ? forcesize : items.size();
	InventoryList *invlist = inv->addList(name, listsize);
	int index = 0;
	for(std::vector<ItemStack>::const_iterator
			i = items.begin(); i != items.end(); ++i){
		if(forcesize != -1 && index == forcesize)
			break;
		invlist->changeItem(index, *i);
		index++;
	}
	while(forcesize != -1 && index < forcesize){
		invlist->deleteItem(index);
		index++;
	}
}

/******************************************************************************/
struct TileAnimationParams read_animation_definition(lua_State *L, int index)
{
	if(index < 0)
		index = lua_gettop(L) + 1 + index;

	struct TileAnimationParams anim;
	anim.type = TAT_NONE;
	if (!lua_istable(L, index))
		return anim;

	anim.type = (TileAnimationType)
		getenumfield(L, index, "type", es_TileAnimationType,
		TAT_NONE);
	if (anim.type == TAT_VERTICAL_FRAMES) {
		// {type="vertical_frames", aspect_w=16, aspect_h=16, length=2.0}
		anim.vertical_frames.aspect_w =
			getintfield_default(L, index, "aspect_w", 16);
		anim.vertical_frames.aspect_h =
			getintfield_default(L, index, "aspect_h", 16);
		anim.vertical_frames.length =
			getfloatfield_default(L, index, "length", 1.0);
	} else if (anim.type == TAT_SHEET_2D) {
		// {type="sheet_2d", frames_w=5, frames_h=3, frame_length=0.5}
		getintfield(L, index, "frames_w",
			anim.sheet_2d.frames_w);
		getintfield(L, index, "frames_h",
			anim.sheet_2d.frames_h);
		getfloatfield(L, index, "frame_length",
			anim.sheet_2d.frame_length);
	}

	return anim;
}

/******************************************************************************/
ToolCapabilities read_tool_capabilities(
		lua_State *L, int table)
{
	ToolCapabilities toolcap;
	getfloatfield(L, table, "full_punch_interval", toolcap.full_punch_interval);
	getintfield(L, table, "max_drop_level", toolcap.max_drop_level);
	lua_getfield(L, table, "groupcaps");
	if(lua_istable(L, -1)){
		int table_groupcaps = lua_gettop(L);
		lua_pushnil(L);
		while(lua_next(L, table_groupcaps) != 0){
			// key at index -2 and value at index -1
			std::string groupname = luaL_checkstring(L, -2);
			if(lua_istable(L, -1)){
				int table_groupcap = lua_gettop(L);
				// This will be created
				ToolGroupCap groupcap;
				// Read simple parameters
				getintfield(L, table_groupcap, "maxlevel", groupcap.maxlevel);
				getintfield(L, table_groupcap, "uses", groupcap.uses);
				// DEPRECATED: maxwear
				float maxwear = 0;
				if (getfloatfield(L, table_groupcap, "maxwear", maxwear)){
					if (maxwear != 0)
						groupcap.uses = 1.0/maxwear;
					else
						groupcap.uses = 0;
					warningstream << "Field \"maxwear\" is deprecated; "
							<< "replace with uses=1/maxwear" << std::endl;
					infostream << script_get_backtrace(L) << std::endl;
				}
				// Read "times" table
				lua_getfield(L, table_groupcap, "times");
				if(lua_istable(L, -1)){
					int table_times = lua_gettop(L);
					lua_pushnil(L);
					while(lua_next(L, table_times) != 0){
						// key at index -2 and value at index -1
						int rating = luaL_checkinteger(L, -2);
						float time = luaL_checknumber(L, -1);
						groupcap.times[rating] = time;
						// removes value, keeps key for next iteration
						lua_pop(L, 1);
					}
				}
				lua_pop(L, 1);
				// Insert groupcap into toolcap
				toolcap.groupcaps[groupname] = groupcap;
			}
			// removes value, keeps key for next iteration
			lua_pop(L, 1);
		}
	}
	lua_pop(L, 1);

	lua_getfield(L, table, "damage_groups");
	if(lua_istable(L, -1)){
		int table_damage_groups = lua_gettop(L);
		lua_pushnil(L);
		while(lua_next(L, table_damage_groups) != 0){
			// key at index -2 and value at index -1
			std::string groupname = luaL_checkstring(L, -2);
			u16 value = luaL_checkinteger(L, -1);
			toolcap.damageGroups[groupname] = value;
			// removes value, keeps key for next iteration
			lua_pop(L, 1);
		}
	}
	lua_pop(L, 1);
	return toolcap;
}

/******************************************************************************/
void push_dig_params(lua_State *L,const DigParams &params)
{
	lua_newtable(L);
	setboolfield(L, -1, "diggable", params.diggable);
	setfloatfield(L, -1, "time", params.time);
	setintfield(L, -1, "wear", params.wear);
}

/******************************************************************************/
void push_hit_params(lua_State *L,const HitParams &params)
{
	lua_newtable(L);
	setintfield(L, -1, "hp", params.hp);
	setintfield(L, -1, "wear", params.wear);
}

/******************************************************************************/

bool getflagsfield(lua_State *L, int table, const char *fieldname,
	FlagDesc *flagdesc, u32 *flags, u32 *flagmask)
{
	lua_getfield(L, table, fieldname);

	bool success = read_flags(L, -1, flagdesc, flags, flagmask);

	lua_pop(L, 1);

	return success;
}

bool read_flags(lua_State *L, int index, FlagDesc *flagdesc,
	u32 *flags, u32 *flagmask)
{
	if (lua_isstring(L, index)) {
		std::string flagstr = lua_tostring(L, index);
		*flags = readFlagString(flagstr, flagdesc, flagmask);
	} else if (lua_istable(L, index)) {
		*flags = read_flags_table(L, index, flagdesc, flagmask);
	} else {
		return false;
	}

	return true;
}

u32 read_flags_table(lua_State *L, int table, FlagDesc *flagdesc, u32 *flagmask)
{
	u32 flags = 0, mask = 0;
	char fnamebuf[64] = "no";

	for (int i = 0; flagdesc[i].name; i++) {
		bool result;

		if (getboolfield(L, table, flagdesc[i].name, result)) {
			mask |= flagdesc[i].flag;
			if (result)
				flags |= flagdesc[i].flag;
		}

		strlcpy(fnamebuf + 2, flagdesc[i].name, sizeof(fnamebuf) - 2);
		if (getboolfield(L, table, fnamebuf, result))
			mask |= flagdesc[i].flag;
	}

	if (flagmask)
		*flagmask = mask;

	return flags;
}

void push_flags_string(lua_State *L, FlagDesc *flagdesc, u32 flags, u32 flagmask)
{
	std::string flagstring = writeFlagString(flags, flagdesc, flagmask);
	lua_pushlstring(L, flagstring.c_str(), flagstring.size());
}

/******************************************************************************/
/* Lua Stored data!                                                           */
/******************************************************************************/

/******************************************************************************/
void read_groups(lua_State *L, int index, ItemGroupList &result)
{
	if (!lua_istable(L,index))
		return;
	result.clear();
	lua_pushnil(L);
	if(index < 0)
		index -= 1;
	while(lua_next(L, index) != 0){
		// key at index -2 and value at index -1
		std::string name = luaL_checkstring(L, -2);
		int rating = luaL_checkinteger(L, -1);
		result[name] = rating;
		// removes value, keeps key for next iteration
		lua_pop(L, 1);
	}
}

/******************************************************************************/
void push_groups(lua_State *L, const ItemGroupList &groups)
{
	lua_newtable(L);
	for (ItemGroupList::const_iterator it = groups.begin(); it != groups.end(); ++it) {
		lua_pushnumber(L, it->second);
		lua_setfield(L, -2, it->first.c_str());
	}
}

/******************************************************************************/
void push_items(lua_State *L, const std::vector<ItemStack> &items)
{
	lua_createtable(L, items.size(), 0);
	for (u32 i = 0; i != items.size(); i++) {
		LuaItemStack::create(L, items[i]);
		lua_rawseti(L, -2, i + 1);
	}
}

/******************************************************************************/
std::vector<ItemStack> read_items(lua_State *L, int index, Server *srv)
{
	if(index < 0)
		index = lua_gettop(L) + 1 + index;

	std::vector<ItemStack> items;
	luaL_checktype(L, index, LUA_TTABLE);
	lua_pushnil(L);
	while (lua_next(L, index)) {
		s32 key = luaL_checkinteger(L, -2);
		if (key < 1) {
			throw LuaError("Invalid inventory list index");
		}
		if (items.size() < (u32) key) {
			items.resize(key);
		}
		items[key - 1] = read_item(L, -1, srv->idef());
		lua_pop(L, 1);
	}
	return items;
}

/******************************************************************************/
void luaentity_get(lua_State *L, u16 id)
{
	// Get luaentities[i]
	lua_getglobal(L, "core");
	lua_getfield(L, -1, "luaentities");
	luaL_checktype(L, -1, LUA_TTABLE);
	lua_pushnumber(L, id);
	lua_gettable(L, -2);
	lua_remove(L, -2); // Remove luaentities
	lua_remove(L, -2); // Remove core
}

/******************************************************************************/
bool read_noiseparams(lua_State *L, int index, NoiseParams *np)
{
	if (index < 0)
		index = lua_gettop(L) + 1 + index;

	if (!lua_istable(L, index))
		return false;

	getfloatfield(L, index, "offset",      np->offset);
	getfloatfield(L, index, "scale",       np->scale);
	getfloatfield(L, index, "persist",     np->persist);
	getfloatfield(L, index, "persistence", np->persist);
	getfloatfield(L, index, "lacunarity",  np->lacunarity);
	getintfield(L,   index, "seed",        np->seed);
	getintfield(L,   index, "octaves",     np->octaves);

	u32 flags    = 0;
	u32 flagmask = 0;
	np->flags = getflagsfield(L, index, "flags", flagdesc_noiseparams,
		&flags, &flagmask) ? flags : NOISE_FLAG_DEFAULTS;

	lua_getfield(L, index, "spread");
	np->spread  = read_v3f(L, -1);
	lua_pop(L, 1);

	return true;
}

void push_noiseparams(lua_State *L, NoiseParams *np)
{
	lua_newtable(L);
	lua_pushnumber(L, np->offset);
	lua_setfield(L, -2, "offset");
	lua_pushnumber(L, np->scale);
	lua_setfield(L, -2, "scale");
	lua_pushnumber(L, np->persist);
	lua_setfield(L, -2, "persistence");
	lua_pushnumber(L, np->lacunarity);
	lua_setfield(L, -2, "lacunarity");
	lua_pushnumber(L, np->seed);
	lua_setfield(L, -2, "seed");
	lua_pushnumber(L, np->octaves);
	lua_setfield(L, -2, "octaves");

	push_flags_string(L, flagdesc_noiseparams, np->flags,
		np->flags);
	lua_setfield(L, -2, "flags");

	push_v3f(L, np->spread);
	lua_setfield(L, -2, "spread");
}

/******************************************************************************/
// Returns depth of json value tree
static int push_json_value_getdepth(const Json::Value &value)
{
	if (!value.isArray() && !value.isObject())
		return 1;

	int maxdepth = 0;
	for (Json::Value::const_iterator it = value.begin();
			it != value.end(); ++it) {
		int elemdepth = push_json_value_getdepth(*it);
		if (elemdepth > maxdepth)
			maxdepth = elemdepth;
	}
	return maxdepth + 1;
}
// Recursive function to convert JSON --> Lua table
static bool push_json_value_helper(lua_State *L, const Json::Value &value,
		int nullindex)
{
	switch(value.type()) {
		case Json::nullValue:
		default:
			lua_pushvalue(L, nullindex);
			break;
		case Json::intValue:
			lua_pushinteger(L, value.asInt());
			break;
		case Json::uintValue:
			lua_pushinteger(L, value.asUInt());
			break;
		case Json::realValue:
			lua_pushnumber(L, value.asDouble());
			break;
		case Json::stringValue:
			{
				const char *str = value.asCString();
				lua_pushstring(L, str ? str : "");
			}
			break;
		case Json::booleanValue:
			lua_pushboolean(L, value.asInt());
			break;
		case Json::arrayValue:
			lua_newtable(L);
			for (Json::Value::const_iterator it = value.begin();
					it != value.end(); ++it) {
				push_json_value_helper(L, *it, nullindex);
				lua_rawseti(L, -2, it.index() + 1);
			}
			break;
		case Json::objectValue:
			lua_newtable(L);
			for (Json::Value::const_iterator it = value.begin();
					it != value.end(); ++it) {
#ifndef JSONCPP_STRING
				const char *str = it.memberName();
				lua_pushstring(L, str ? str : "");
#else
				std::string str = it.name();
				lua_pushstring(L, str.c_str());
#endif
				push_json_value_helper(L, *it, nullindex);
				lua_rawset(L, -3);
			}
			break;
	}
	return true;
}
// converts JSON --> Lua table; returns false if lua stack limit exceeded
// nullindex: Lua stack index of value to use in place of JSON null
bool push_json_value(lua_State *L, const Json::Value &value, int nullindex)
{
	if(nullindex < 0)
		nullindex = lua_gettop(L) + 1 + nullindex;

	int depth = push_json_value_getdepth(value);

	// The maximum number of Lua stack slots used at each recursion level
	// of push_json_value_helper is 2, so make sure there a depth * 2 slots
	if (lua_checkstack(L, depth * 2))
		return push_json_value_helper(L, value, nullindex);
	else
		return false;
}

// Converts Lua table --> JSON
void read_json_value(lua_State *L, Json::Value &root, int index, u8 recursion)
{
	if (recursion > 16) {
		throw SerializationError("Maximum recursion depth exceeded");
	}
	int type = lua_type(L, index);
	if (type == LUA_TBOOLEAN) {
		root = (bool) lua_toboolean(L, index);
	} else if (type == LUA_TNUMBER) {
		root = lua_tonumber(L, index);
	} else if (type == LUA_TSTRING) {
		size_t len;
		const char *str = lua_tolstring(L, index, &len);
		root = std::string(str, len);
	} else if (type == LUA_TTABLE) {
		lua_pushnil(L);
		while (lua_next(L, index)) {
			// Key is at -2 and value is at -1
			Json::Value value;
			read_json_value(L, value, lua_gettop(L), recursion + 1);

			Json::ValueType roottype = root.type();
			int keytype = lua_type(L, -1);
			if (keytype == LUA_TNUMBER) {
				lua_Number key = lua_tonumber(L, -1);
				if (roottype != Json::nullValue && roottype != Json::arrayValue) {
					throw SerializationError("Can't mix array and object values in JSON");
				} else if (key < 1) {
					throw SerializationError("Can't use zero-based or negative indexes in JSON");
				} else if (floor(key) != key) {
					throw SerializationError("Can't use indexes with a fractional part in JSON");
				}
				root[(Json::ArrayIndex) key - 1] = value;
			} else if (keytype == LUA_TSTRING) {
				if (roottype != Json::nullValue && roottype != Json::objectValue) {
					throw SerializationError("Can't mix array and object values in JSON");
				}
				root[lua_tostring(L, -1)] = value;
			} else {
				throw SerializationError("Lua key to convert to JSON is not a string or number");
			}
		}
	} else if (type == LUA_TNIL) {
		root = Json::nullValue;
	} else {
		throw SerializationError("Can only store booleans, numbers, strings, objects, arrays, and null in JSON");
	}
	lua_pop(L, 1); // Pop value
}

void push_pointed_thing(lua_State *L, const PointedThing &pointed, bool csm)
{
	lua_newtable(L);
	if (pointed.type == POINTEDTHING_NODE) {
		lua_pushstring(L, "node");
		lua_setfield(L, -2, "type");
		push_v3s16(L, pointed.node_undersurface);
		lua_setfield(L, -2, "under");
		push_v3s16(L, pointed.node_abovesurface);
		lua_setfield(L, -2, "above");
	} else if (pointed.type == POINTEDTHING_OBJECT) {
		lua_pushstring(L, "object");
		lua_setfield(L, -2, "type");

		if (csm) {
			lua_pushinteger(L, pointed.object_id);
			lua_setfield(L, -2, "id");
		} else {
			push_objectRef(L, pointed.object_id);
			lua_setfield(L, -2, "ref");
		}
	} else {
		lua_pushstring(L, "nothing");
		lua_setfield(L, -2, "type");
	}
}

void push_objectRef(lua_State *L, const u16 id)
{
	// Get core.object_refs[i]
	lua_getglobal(L, "core");
	lua_getfield(L, -1, "object_refs");
	luaL_checktype(L, -1, LUA_TTABLE);
	lua_pushnumber(L, id);
	lua_gettable(L, -2);
	lua_remove(L, -2); // object_refs
	lua_remove(L, -2); // core
}


code:
/*
Minetest
Copyright (C) 2013 celeron55, Perttu Ahola <celeron55@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.
*/

/******************************************************************************/
/******************************************************************************/
/* WARNING!!!! do NOT add this header in any include file or any code file    */
/*             not being a script/modapi file!!!!!!!!                         */
/******************************************************************************/
/******************************************************************************/

#ifndef C_CONTENT_H_
#define C_CONTENT_H_

extern "C" {
#include <lua.h>
}

#include <iostream>
#include <vector>

#include "irrlichttypes_bloated.h"
#include "util/string.h"
#include "itemgroup.h"
#include "itemdef.h"
#include "c_types.h"

namespace Json { class Value; }

struct MapNode;
class INodeDefManager;
struct PointedThing;
struct ItemStack;
struct ItemDefinition;
struct ToolCapabilities;
struct ObjectProperties;
struct SimpleSoundSpec;
struct ServerSoundParams;
class Inventory;
struct NodeBox;
struct ContentFeatures;
struct TileDef;
class Server;
struct DigParams;
struct HitParams;
struct EnumString;
struct NoiseParams;
class Schematic;

ContentFeatures    read_content_features     (lua_State *L, int index);
void               push_content_features     (lua_State *L,
                                              const ContentFeatures &c);

void               push_nodebox              (lua_State *L,
                                              const NodeBox &box);
void               push_box                  (lua_State *L,
                                              const std::vector<aabb3f> &box);

void               push_palette              (lua_State *L,
                                              const std::vector<video::SColor> *palette);

TileDef            read_tiledef              (lua_State *L, int index,
                                              u8 drawtype);

void               read_soundspec            (lua_State *L, int index,
                                              SimpleSoundSpec &spec);
NodeBox            read_nodebox              (lua_State *L, int index);

void               read_server_sound_params  (lua_State *L, int index,
                                              ServerSoundParams &params);

void               push_dig_params           (lua_State *L,
                                              const DigParams &params);
void               push_hit_params           (lua_State *L,
                                              const HitParams &params);

ItemStack          read_item                 (lua_State *L, int index, IItemDefManager *idef);

struct TileAnimationParams read_animation_definition(lua_State *L, int index);

ToolCapabilities   read_tool_capabilities    (lua_State *L, int table);
void               push_tool_capabilities    (lua_State *L,
                                              const ToolCapabilities &prop);

void read_item_definition (lua_State *L, int index, const ItemDefinition &default_def,
		ItemDefinition &def);
void               push_item_definition      (lua_State *L,
                                              const ItemDefinition &i);
void               push_item_definition_full (lua_State *L,
                                              const ItemDefinition &i);

void               read_object_properties    (lua_State *L, int index,
                                              ObjectProperties *prop,
                                              IItemDefManager *idef);
void               push_object_properties    (lua_State *L,
                                              ObjectProperties *prop);

void               push_inventory_list       (lua_State *L,
                                              Inventory *inv,
                                              const char *name);
void               read_inventory_list       (lua_State *L, int tableindex,
                                              Inventory *inv, const char *name,
                                              Server *srv, int forcesize=-1);

MapNode            readnode                  (lua_State *L, int index,
                                              INodeDefManager *ndef);
void               pushnode                  (lua_State *L, const MapNode &n,
                                              INodeDefManager *ndef);

NodeBox            read_nodebox              (lua_State *L, int index);

void               read_groups               (lua_State *L, int index,
                                              ItemGroupList &result);

void               push_groups               (lua_State *L,
                                              const ItemGroupList &groups);

//TODO rename to "read_enum_field"
int                getenumfield              (lua_State *L, int table,
                                              const char *fieldname,
                                              const EnumString *spec,
                                              int default_);

bool               getflagsfield             (lua_State *L, int table,
                                              const char *fieldname,
                                              FlagDesc *flagdesc,
                                              u32 *flags, u32 *flagmask);

bool               read_flags                (lua_State *L, int index,
                                              FlagDesc *flagdesc,
                                              u32 *flags, u32 *flagmask);

void               push_flags_string         (lua_State *L, FlagDesc *flagdesc,
                                              u32 flags, u32 flagmask);

u32                read_flags_table          (lua_State *L, int table,
                                              FlagDesc *flagdesc, u32 *flagmask);

void               push_items                (lua_State *L,
                                              const std::vector<ItemStack> &items);

std::vector<ItemStack> read_items            (lua_State *L,
                                              int index,
                                              Server* srv);

void               read_soundspec            (lua_State *L,
                                              int index,
                                              SimpleSoundSpec &spec);
void               push_soundspec            (lua_State *L,
                                              const SimpleSoundSpec &spec);

bool               string_to_enum            (const EnumString *spec,
                                              int &result,
                                              const std::string &str);

bool               read_noiseparams          (lua_State *L, int index,
                                              NoiseParams *np);
void               push_noiseparams          (lua_State *L, NoiseParams *np);

void               luaentity_get             (lua_State *L,u16 id);

bool               push_json_value           (lua_State *L,
                                              const Json::Value &value,
                                              int nullindex);
void               read_json_value           (lua_State *L, Json::Value &root,
                                              int index, u8 recursion = 0);

void               push_pointed_thing        (lua_State *L, const PointedThing &pointed, bool csm = false);

void               push_objectRef            (lua_State *L, const u16 id);

extern struct EnumString es_TileAnimationType[];

#endif /* C_CONTENT_H_ */

repo_name: pgimeno/minetest

license: unknown


code:
/*
Minetest
Copyright (C) 2013 celeron55, Perttu Ahola <celeron55@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.
*/

extern "C" {
#include "lua.h"
#include "lauxlib.h"
}

#include "util/numeric.h"
#include "util/serialize.h"
#include "util/string.h"
#include "common/c_converter.h"
#include "common/c_internal.h"
#include "constants.h"

#define CHECK_TYPE(index, name, type) do { \
		int t = lua_type(L, (index)); \
		if (t != (type)) { \
			std::string traceback = script_get_backtrace(L); \
			throw LuaError(std::string("Invalid ") + (name) + \
				" (expected " + lua_typename(L, (type)) + \
				" got " + lua_typename(L, t) + ").\n" + traceback); \
		} \
	} while(0)
#define CHECK_POS_COORD(name) CHECK_TYPE(-1, "position coordinate '" name "'", LUA_TNUMBER)
#define CHECK_FLOAT_RANGE(value, name) \
if (value < F1000_MIN || value > F1000_MAX) { \
	std::ostringstream error_text; \
	error_text << "Invalid float vector dimension range '" name "' " << \
	"(expected " << F1000_MIN << " < " name " < " << F1000_MAX << \
	" got " << value << ")." << std::endl; \
	throw LuaError(error_text.str()); \
}
#define CHECK_POS_TAB(index) CHECK_TYPE(index, "position", LUA_TTABLE)

void push_v3f(lua_State *L, v3f p)
{
	lua_newtable(L);
	lua_pushnumber(L, p.X);
	lua_setfield(L, -2, "x");
	lua_pushnumber(L, p.Y);
	lua_setfield(L, -2, "y");
	lua_pushnumber(L, p.Z);
	lua_setfield(L, -2, "z");
}

void push_v2f(lua_State *L, v2f p)
{
	lua_newtable(L);
	lua_pushnumber(L, p.X);
	lua_setfield(L, -2, "x");
	lua_pushnumber(L, p.Y);
	lua_setfield(L, -2, "y");
}

v2s16 read_v2s16(lua_State *L, int index)
{
	v2s16 p;
	CHECK_POS_TAB(index);
	lua_getfield(L, index, "x");
	p.X = lua_tonumber(L, -1);
	lua_pop(L, 1);
	lua_getfield(L, index, "y");
	p.Y = lua_tonumber(L, -1);
	lua_pop(L, 1);
	return p;
}

v2s16 check_v2s16(lua_State *L, int index)
{
	v2s16 p;
	CHECK_POS_TAB(index);
	lua_getfield(L, index, "x");
	CHECK_POS_COORD("x");
	p.X = lua_tonumber(L, -1);
	lua_pop(L, 1);
	lua_getfield(L, index, "y");
	CHECK_POS_COORD("y");
	p.Y = lua_tonumber(L, -1);
	lua_pop(L, 1);
	return p;
}

void push_v2s16(lua_State *L, v2s16 p)
{
	lua_newtable(L);
	lua_pushnumber(L, p.X);
	lua_setfield(L, -2, "x");
	lua_pushnumber(L, p.Y);
	lua_setfield(L, -2, "y");
}

void push_v2s32(lua_State *L, v2s32 p)
{
	lua_newtable(L);
	lua_pushnumber(L, p.X);
	lua_setfield(L, -2, "x");
	lua_pushnumber(L, p.Y);
	lua_setfield(L, -2, "y");
}

v2s32 read_v2s32(lua_State *L, int index)
{
	v2s32 p;
	CHECK_POS_TAB(index);
	lua_getfield(L, index, "x");
	p.X = lua_tonumber(L, -1);
	lua_pop(L, 1);
	lua_getfield(L, index, "y");
	p.Y = lua_tonumber(L, -1);
	lua_pop(L, 1);
	return p;
}

v2f read_v2f(lua_State *L, int index)
{
	v2f p;
	CHECK_POS_TAB(index);
	lua_getfield(L, index, "x");
	p.X = lua_tonumber(L, -1);
	lua_pop(L, 1);
	lua_getfield(L, index, "y");
	p.Y = lua_tonumber(L, -1);
	lua_pop(L, 1);
	return p;
}

v2f check_v2f(lua_State *L, int index)
{
	v2f p;
	CHECK_POS_TAB(index);
	lua_getfield(L, index, "x");
	CHECK_POS_COORD("x");
	p.X = lua_tonumber(L, -1);
	lua_pop(L, 1);
	lua_getfield(L, index, "y");
	CHECK_POS_COORD("y");
	p.Y = lua_tonumber(L, -1);
	lua_pop(L, 1);
	return p;
}

v3f read_v3f(lua_State *L, int index)
{
	v3f pos;
	CHECK_POS_TAB(index);
	lua_getfield(L, index, "x");
	pos.X = lua_tonumber(L, -1);
	lua_pop(L, 1);
	lua_getfield(L, index, "y");
	pos.Y = lua_tonumber(L, -1);
	lua_pop(L, 1);
	lua_getfield(L, index, "z");
	pos.Z = lua_tonumber(L, -1);
	lua_pop(L, 1);
	return pos;
}

v3f check_v3f(lua_State *L, int index)
{
	v3f pos;
	CHECK_POS_TAB(index);
	lua_getfield(L, index, "x");
	CHECK_POS_COORD("x");
	pos.X = lua_tonumber(L, -1);
	CHECK_FLOAT_RANGE(pos.X, "x")
	lua_pop(L, 1);
	lua_getfield(L, index, "y");
	CHECK_POS_COORD("y");
	pos.Y = lua_tonumber(L, -1);
	CHECK_FLOAT_RANGE(pos.Y, "y")
	lua_pop(L, 1);
	lua_getfield(L, index, "z");
	CHECK_POS_COORD("z");
	pos.Z = lua_tonumber(L, -1);
	CHECK_FLOAT_RANGE(pos.Z, "z")
	lua_pop(L, 1);
	return pos;
}

void push_ARGB8(lua_State *L, video::SColor color)
{
	lua_newtable(L);
	lua_pushnumber(L, color.getAlpha());
	lua_setfield(L, -2, "a");
	lua_pushnumber(L, color.getRed());
	lua_setfield(L, -2, "r");
	lua_pushnumber(L, color.getGreen());
	lua_setfield(L, -2, "g");
	lua_pushnumber(L, color.getBlue());
	lua_setfield(L, -2, "b");
}

void pushFloatPos(lua_State *L, v3f p)
{
	p /= BS;
	push_v3f(L, p);
}

v3f checkFloatPos(lua_State *L, int index)
{
	return check_v3f(L, index) * BS;
}

void push_v3s16(lua_State *L, v3s16 p)
{
	lua_newtable(L);
	lua_pushnumber(L, p.X);
	lua_setfield(L, -2, "x");
	lua_pushnumber(L, p.Y);
	lua_setfield(L, -2, "y");
	lua_pushnumber(L, p.Z);
	lua_setfield(L, -2, "z");
}

v3s16 read_v3s16(lua_State *L, int index)
{
	// Correct rounding at <0
	v3f pf = read_v3f(L, index);
	return floatToInt(pf, 1.0);
}

v3s16 check_v3s16(lua_State *L, int index)
{
	// Correct rounding at <0
	v3f pf = check_v3f(L, index);
	return floatToInt(pf, 1.0);
}

bool read_color(lua_State *L, int index, video::SColor *color)
{
	if (lua_istable(L, index)) {
		*color = read_ARGB8(L, index);
	} else if (lua_isnumber(L, index)) {
		color->set(lua_tonumber(L, index));
	} else if (lua_isstring(L, index)) {
		video::SColor parsed_color;
		if (!parseColorString(lua_tostring(L, index), parsed_color, true))
			return false;

		*color = parsed_color;
	} else {
		return false;
	}

	return true;
}

video::SColor read_ARGB8(lua_State *L, int index)
{
	video::SColor color(0);
	CHECK_TYPE(index, "ARGB color", LUA_TTABLE);
	lua_getfield(L, index, "a");
	color.setAlpha(lua_isnumber(L, -1) ? lua_tonumber(L, -1) : 0xFF);
	lua_pop(L, 1);
	lua_getfield(L, index, "r");
	color.setRed(lua_tonumber(L, -1));
	lua_pop(L, 1);
	lua_getfield(L, index, "g");
	color.setGreen(lua_tonumber(L, -1));
	lua_pop(L, 1);
	lua_getfield(L, index, "b");
	color.setBlue(lua_tonumber(L, -1));
	lua_pop(L, 1);
	return color;
}

aabb3f read_aabb3f(lua_State *L, int index, f32 scale)
{
	aabb3f box;
	if(lua_istable(L, index)){
		lua_rawgeti(L, index, 1);
		box.MinEdge.X = lua_tonumber(L, -1) * scale;
		lua_pop(L, 1);
		lua_rawgeti(L, index, 2);
		box.MinEdge.Y = lua_tonumber(L, -1) * scale;
		lua_pop(L, 1);
		lua_rawgeti(L, index, 3);
		box.MinEdge.Z = lua_tonumber(L, -1) * scale;
		lua_pop(L, 1);
		lua_rawgeti(L, index, 4);
		box.MaxEdge.X = lua_tonumber(L, -1) * scale;
		lua_pop(L, 1);
		lua_rawgeti(L, index, 5);
		box.MaxEdge.Y = lua_tonumber(L, -1) * scale;
		lua_pop(L, 1);
		lua_rawgeti(L, index, 6);
		box.MaxEdge.Z = lua_tonumber(L, -1) * scale;
		lua_pop(L, 1);
	}
	return box;
}

void push_aabb3f(lua_State *L, aabb3f box)
{
	lua_newtable(L);
	lua_pushnumber(L, box.MinEdge.X);
	lua_rawseti(L, -2, 1);
	lua_pushnumber(L, box.MinEdge.Y);
	lua_rawseti(L, -2, 2);
	lua_pushnumber(L, box.MinEdge.Z);
	lua_rawseti(L, -2, 3);
	lua_pushnumber(L, box.MaxEdge.X);
	lua_rawseti(L, -2, 4);
	lua_pushnumber(L, box.MaxEdge.Y);
	lua_rawseti(L, -2, 5);
	lua_pushnumber(L, box.MaxEdge.Z);
	lua_rawseti(L, -2, 6);
}

std::vector<aabb3f> read_aabb3f_vector(lua_State *L, int index, f32 scale)
{
	std::vector<aabb3f> boxes;
	if(lua_istable(L, index)){
		int n = lua_objlen(L, index);
		// Check if it's a single box or a list of boxes
		bool possibly_single_box = (n == 6);
		for(int i = 1; i <= n && possibly_single_box; i++){
			lua_rawgeti(L, index, i);
			if(!lua_isnumber(L, -1))
				possibly_single_box = false;
			lua_pop(L, 1);
		}
		if(possibly_single_box){
			// Read a single box
			boxes.push_back(read_aabb3f(L, index, scale));
		} else {
			// Read a list of boxes
			for(int i = 1; i <= n; i++){
				lua_rawgeti(L, index, i);
				boxes.push_back(read_aabb3f(L, -1, scale));
				lua_pop(L, 1);
			}
		}
	}
	return boxes;
}

size_t read_stringlist(lua_State *L, int index, std::vector<std::string> *result)
{
	if (index < 0)
		index = lua_gettop(L) + 1 + index;

	size_t num_strings = 0;

	if (lua_istable(L, index)) {
		lua_pushnil(L);
		while (lua_next(L, index)) {
			if (lua_isstring(L, -1)) {
				result->push_back(lua_tostring(L, -1));
				num_strings++;
			}
			lua_pop(L, 1);
		}
	} else if (lua_isstring(L, index)) {
		result->push_back(lua_tostring(L, index));
		num_strings++;
	}

	return num_strings;
}

/*
	Table field getters
*/

bool getstringfield(lua_State *L, int table,
		const char *fieldname, std::string &result)
{
	lua_getfield(L, table, fieldname);
	bool got = false;
	if(lua_isstring(L, -1)){
		size_t len = 0;
		const char *ptr = lua_tolstring(L, -1, &len);
		if (ptr) {
			result.assign(ptr, len);
			got = true;
		}
	}
	lua_pop(L, 1);
	return got;
}

bool getintfield(lua_State *L, int table,
		const char *fieldname, int &result)
{
	lua_getfield(L, table, fieldname);
	bool got = false;
	if(lua_isnumber(L, -1)){
		result = lua_tointeger(L, -1);
		got = true;
	}
	lua_pop(L, 1);
	return got;
}

bool getintfield(lua_State *L, int table,
		const char *fieldname, u8 &result)
{
	lua_getfield(L, table, fieldname);
	bool got = false;
	if(lua_isnumber(L, -1)){
		result = lua_tointeger(L, -1);
		got = true;
	}
	lua_pop(L, 1);
	return got;
}

bool getintfield(lua_State *L, int table,
		const char *fieldname, u16 &result)
{
	lua_getfield(L, table, fieldname);
	bool got = false;
	if(lua_isnumber(L, -1)){
		result = lua_tointeger(L, -1);
		got = true;
	}
	lua_pop(L, 1);
	return got;
}

bool getintfield(lua_State *L, int table,
		const char *fieldname, u32 &result)
{
	lua_getfield(L, table, fieldname);
	bool got = false;
	if(lua_isnumber(L, -1)){
		result = lua_tointeger(L, -1);
		got = true;
	}
	lua_pop(L, 1);
	return got;
}

bool getfloatfield(lua_State *L, int table,
		const char *fieldname, float &result)
{
	lua_getfield(L, table, fieldname);
	bool got = false;
	if(lua_isnumber(L, -1)){
		result = lua_tonumber(L, -1);
		got = true;
	}
	lua_pop(L, 1);
	return got;
}

bool getboolfield(lua_State *L, int table,
		const char *fieldname, bool &result)
{
	lua_getfield(L, table, fieldname);
	bool got = false;
	if(lua_isboolean(L, -1)){
		result = lua_toboolean(L, -1);
		got = true;
	}
	lua_pop(L, 1);
	return got;
}

size_t getstringlistfield(lua_State *L, int table, const char *fieldname,
		std::vector<std::string> *result)
{
	lua_getfield(L, table, fieldname);

	size_t num_strings_read = read_stringlist(L, -1, result);

	lua_pop(L, 1);
	return num_strings_read;
}

std::string checkstringfield(lua_State *L, int table,
		const char *fieldname)
{
	lua_getfield(L, table, fieldname);
	CHECK_TYPE(-1, std::string("field \"") + fieldname + '"', LUA_TSTRING);
	size_t len;
	const char *s = lua_tolstring(L, -1, &len);
	lua_pop(L, 1);
	return std::string(s, len);
}

std::string getstringfield_default(lua_State *L, int table,
		const char *fieldname, const std::string &default_)
{
	std::string result = default_;
	getstringfield(L, table, fieldname, result);
	return result;
}

int getintfield_default(lua_State *L, int table,
		const char *fieldname, int default_)
{
	int result = default_;
	getintfield(L, table, fieldname, result);
	return result;
}

float getfloatfield_default(lua_State *L, int table,
		const char *fieldname, float default_)
{
	float result = default_;
	getfloatfield(L, table, fieldname, result);
	return result;
}

bool getboolfield_default(lua_State *L, int table,
		const char *fieldname, bool default_)
{
	bool result = default_;
	getboolfield(L, table, fieldname, result);
	return result;
}

void setstringfield(lua_State *L, int table,
		const char *fieldname, const char *value)
{
	lua_pushstring(L, value);
	if(table < 0)
		table -= 1;
	lua_setfield(L, table, fieldname);
}

void setintfield(lua_State *L, int table,
		const char *fieldname, int value)
{
	lua_pushinteger(L, value);
	if(table < 0)
		table -= 1;
	lua_setfield(L, table, fieldname);
}

void setfloatfield(lua_State *L, int table,
		const char *fieldname, float value)
{
	lua_pushnumber(L, value);
	if(table < 0)
		table -= 1;
	lua_setfield(L, table, fieldname);
}

void setboolfield(lua_State *L, int table,
		const char *fieldname, bool value)
{
	lua_pushboolean(L, value);
	if(table < 0)
		table -= 1;
	lua_setfield(L, table, fieldname);
}

////
//// Array table slices
////

size_t write_array_slice_float(
	lua_State *L,
	int table_index,
	float *data,
	v3u16 data_size,
	v3u16 slice_offset,
	v3u16 slice_size)
{
	v3u16 pmin, pmax(data_size);

	if (slice_offset.X > 0) {
		slice_offset.X--;
		pmin.X = slice_offset.X;
		pmax.X = MYMIN(slice_offset.X + slice_size.X, data_size.X);
	}

	if (slice_offset.Y > 0) {
		slice_offset.Y--;
		pmin.Y = slice_offset.Y;
		pmax.Y = MYMIN(slice_offset.Y + slice_size.Y, data_size.Y);
	}

	if (slice_offset.Z > 0) {
		slice_offset.Z--;
		pmin.Z = slice_offset.Z;
		pmax.Z = MYMIN(slice_offset.Z + slice_size.Z, data_size.Z);
	}

	const u32 ystride = data_size.X;
	const u32 zstride = data_size.X * data_size.Y;

	u32 elem_index = 1;
	for (u32 z = pmin.Z; z != pmax.Z; z++)
	for (u32 y = pmin.Y; y != pmax.Y; y++)
	for (u32 x = pmin.X; x != pmax.X; x++) {
		u32 i = z * zstride + y * ystride + x;
		lua_pushnumber(L, data[i]);
		lua_rawseti(L, table_index, elem_index);
		elem_index++;
	}

	return elem_index - 1;
}

size_t write_array_slice_u16(
	lua_State *L,
	int table_index,
	u16 *data,
	v3u16 data_size,
	v3u16 slice_offset,
	v3u16 slice_size)
{
	v3u16 pmin, pmax(data_size);

	if (slice_offset.X > 0) {
		slice_offset.X--;
		pmin.X = slice_offset.X;
		pmax.X = MYMIN(slice_offset.X + slice_size.X, data_size.X);
	}

	if (slice_offset.Y > 0) {
		slice_offset.Y--;
		pmin.Y = slice_offset.Y;
		pmax.Y = MYMIN(slice_offset.Y + slice_size.Y, data_size.Y);
	}

	if (slice_offset.Z > 0) {
		slice_offset.Z--;
		pmin.Z = slice_offset.Z;
		pmax.Z = MYMIN(slice_offset.Z + slice_size.Z, data_size.Z);
	}

	const u32 ystride = data_size.X;
	const u32 zstride = data_size.X * data_size.Y;

	u32 elem_index = 1;
	for (u32 z = pmin.Z; z != pmax.Z; z++)
	for (u32 y = pmin.Y; y != pmax.Y; y++)
	for (u32 x = pmin.X; x != pmax.X; x++) {
		u32 i = z * zstride + y * ystride + x;
		lua_pushinteger(L, data[i]);
		lua_rawseti(L, table_index, elem_index);
		elem_index++;
	}

	return elem_index - 1;
}


code:
/*
Minetest
Copyright (C) 2013 celeron55, Perttu Ahola <celeron55@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.
*/

/******************************************************************************/
/******************************************************************************/
/* WARNING!!!! do NOT add this header in any include file or any code file    */
/*             not being a script/modapi file!!!!!!!!                         */
/******************************************************************************/
/******************************************************************************/
#ifndef C_CONVERTER_H_
#define C_CONVERTER_H_

#include <vector>
#include "util/cpp11_container.h"

#include "irrlichttypes_bloated.h"
#include "common/c_types.h"

extern "C" {
#include <lua.h>
}

std::string        getstringfield_default(lua_State *L, int table,
                             const char *fieldname, const std::string &default_);
bool               getboolfield_default(lua_State *L, int table,
                             const char *fieldname, bool default_);
float              getfloatfield_default(lua_State *L, int table,
                             const char *fieldname, float default_);
int                getintfield_default           (lua_State *L, int table,
                             const char *fieldname, int default_);

bool               getstringfield(lua_State *L, int table,
                             const char *fieldname, std::string &result);
size_t             getstringlistfield(lua_State *L, int table,
                             const char *fieldname,
                             std::vector<std::string> *result);
bool               getintfield(lua_State *L, int table,
                             const char *fieldname, int &result);
bool               getintfield(lua_State *L, int table,
                             const char *fieldname, u8 &result);
bool               getintfield(lua_State *L, int table,
                             const char *fieldname, u16 &result);
bool               getintfield(lua_State *L, int table,
                             const char *fieldname, u32 &result);
void               read_groups(lua_State *L, int index,
                             UNORDERED_MAP<std::string, int> &result);
bool               getboolfield(lua_State *L, int table,
                             const char *fieldname, bool &result);
bool               getfloatfield(lua_State *L, int table,
                             const char *fieldname, float &result);

std::string        checkstringfield(lua_State *L, int table,
                             const char *fieldname);

void               setstringfield(lua_State *L, int table,
                             const char *fieldname, const char *value);
void               setintfield(lua_State *L, int table,
                             const char *fieldname, int value);
void               setfloatfield(lua_State *L, int table,
                             const char *fieldname, float value);
void               setboolfield(lua_State *L, int table,
                             const char *fieldname, bool value);
void               setstringfield(lua_State *L, int table,
                             const char *fieldname, const char *value);

v3f                 checkFloatPos       (lua_State *L, int index);
v2f                 check_v2f           (lua_State *L, int index);
v2s16               check_v2s16         (lua_State *L, int index);
v3f                 check_v3f           (lua_State *L, int index);
v3s16               check_v3s16         (lua_State *L, int index);

v3f                 read_v3f            (lua_State *L, int index);
v2f                 read_v2f            (lua_State *L, int index);
v2s16               read_v2s16          (lua_State *L, int index);
v2s32               read_v2s32          (lua_State *L, int index);
video::SColor       read_ARGB8          (lua_State *L, int index);
bool                read_color          (lua_State *L, int index,
                                         video::SColor *color);

aabb3f              read_aabb3f         (lua_State *L, int index, f32 scale);
v3s16               read_v3s16          (lua_State *L, int index);
std::vector<aabb3f> read_aabb3f_vector  (lua_State *L, int index, f32 scale);
size_t              read_stringlist     (lua_State *L, int index,
                                         std::vector<std::string> *result);

void                push_v2s16          (lua_State *L, v2s16 p);
void                push_v2s32          (lua_State *L, v2s32 p);
void                push_v3s16          (lua_State *L, v3s16 p);
void                push_aabb3f         (lua_State *L, aabb3f box);
void                push_ARGB8          (lua_State *L, video::SColor color);
void                pushFloatPos        (lua_State *L, v3f p);
void                push_v3f            (lua_State *L, v3f p);
void                push_v2f            (lua_State *L, v2f p);

void                warn_if_field_exists(lua_State *L, int table,
                                         const char *fieldname,
                                         const std::string &message);

size_t write_array_slice_float(lua_State *L, int table_index, float *data,
	v3u16 data_size, v3u16 slice_offset, v3u16 slice_size);
size_t write_array_slice_u16(lua_State *L, int table_index, u16 *data,
	v3u16 data_size, v3u16 slice_offset, v3u16 slice_size);

#endif /* C_CONVERTER_H_ */


code:
/*
Minetest
Copyright (C) 2013 celeron55, Perttu Ahola <celeron55@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.
*/

#include "common/c_internal.h"
#include "debug.h"
#include "log.h"
#include "settings.h"

std::string script_get_backtrace(lua_State *L)
{
	std::string s;
	lua_getglobal(L, "debug");
	if(lua_istable(L, -1)){
		lua_getfield(L, -1, "traceback");
		if(lua_isfunction(L, -1)) {
			lua_call(L, 0, 1);
			if(lua_isstring(L, -1)){
				s = lua_tostring(L, -1);
			}
		}
		lua_pop(L, 1);
	}
	lua_pop(L, 1);
	return s;
}

int script_error_handler(lua_State *L) {
	lua_getglobal(L, "debug");
	if (!lua_istable(L, -1)) {
		lua_pop(L, 1);
		return 1;
	}
	lua_getfield(L, -1, "traceback");
	if (!lua_isfunction(L, -1)) {
		lua_pop(L, 2);
		return 1;
	}
	lua_pushvalue(L, 1);
	lua_pushinteger(L, 2);
	lua_call(L, 2, 1);
	return 1;
}

int script_exception_wrapper(lua_State *L, lua_CFunction f)
{
	try {
		return f(L);  // Call wrapped function and return result.
	} catch (const char *s) {  // Catch and convert exceptions.
		lua_pushstring(L, s);
	} catch (std::exception &e) {
		lua_pushstring(L, e.what());
	}
	return lua_error(L);  // Rethrow as a Lua error.
}

/*
 * Note that we can't get tracebacks for LUA_ERRMEM or LUA_ERRERR (without
 * hacking Lua internals).  For LUA_ERRMEM, this is because memory errors will
 * not execute the the error handler, and by the time lua_pcall returns the
 * execution stack will have already been unwound.  For LUA_ERRERR, there was
 * another error while trying to generate a backtrace from a LUA_ERRRUN.  It is
 * presumed there is an error with the internal Lua state and thus not possible
 * to gather a coherent backtrace.  Realistically, the best we can do here is
 * print which C function performed the failing pcall.
 */
void script_error(lua_State *L, int pcall_result, const char *mod, const char *fxn)
{
	if (pcall_result == 0)
		return;

	const char *err_type;
	switch (pcall_result) {
	case LUA_ERRRUN:
		err_type = "Runtime";
		break;
	case LUA_ERRMEM:
		err_type = "OOM";
		break;
	case LUA_ERRERR:
		err_type = "Double fault";
		break;
	default:
		err_type = "Unknown";
	}

	if (!mod)
		mod = "??";

	if (!fxn)
		fxn = "??";

	const char *err_descr = lua_tostring(L, -1);
	if (!err_descr)
		err_descr = "<no description>";

	char buf[256];
	snprintf(buf, sizeof(buf), "%s error from mod '%s' in callback %s(): ",
		err_type, mod, fxn);

	std::string err_msg(buf);
	err_msg += err_descr;

	if (pcall_result == LUA_ERRMEM) {
		err_msg += "\nCurrent Lua memory usage: "
			+ itos(lua_gc(L, LUA_GCCOUNT, 0) >> 10) + " MB";
	}

	throw LuaError(err_msg);
}

// Push the list of callbacks (a lua table).
// Then push nargs arguments.
// Then call this function, which
// - runs the callbacks
// - replaces the table and arguments with the return value,
//     computed depending on mode
void script_run_callbacks_f(lua_State *L, int nargs,
	RunCallbacksMode mode, const char *fxn)
{
	FATAL_ERROR_IF(lua_gettop(L) < nargs + 1, "Not enough arguments");

	// Insert error handler
	PUSH_ERROR_HANDLER(L);
	int error_handler = lua_gettop(L) - nargs - 1;
	lua_insert(L, error_handler);

	// Insert run_callbacks between error handler and table
	lua_getglobal(L, "core");
	lua_getfield(L, -1, "run_callbacks");
	lua_remove(L, -2);
	lua_insert(L, error_handler + 1);

	// Insert mode after table
	lua_pushnumber(L, (int) mode);
	lua_insert(L, error_handler + 3);

	// Stack now looks like this:
	// ... <error handler> <run_callbacks> <table> <mode> <arg#1> <arg#2> ... <arg#n>

	int result = lua_pcall(L, nargs + 2, 1, error_handler);
	if (result != 0)
		script_error(L, result, NULL, fxn);

	lua_remove(L, error_handler);
}

void log_deprecated(lua_State *L, const std::string &message)
{
	static bool configured = false;
	static bool do_log     = false;
	static bool do_error   = false;

	// Only read settings on first call
	if (!configured) {
		std::string value = g_settings->get("deprecated_lua_api_handling");
		if (value == "log") {
			do_log = true;
		} else if (value == "error") {
			do_log   = true;
			do_error = true;
		}
	}

	if (do_log) {
		warningstream << message;
		if (L) { // L can be NULL if we get called from scripting_game.cpp
			lua_Debug ar;
			FATAL_ERROR_IF(!lua_getstack(L, 2, &ar), "lua_getstack() failed");
			FATAL_ERROR_IF(!lua_getinfo(L, "Sl", &ar), "lua_getinfo() failed");
			warningstream << " (at " << ar.short_src << ":" << ar.currentline << ")";
		}
		warningstream << std::endl;

		if (L) {
			if (do_error)
				script_error(L, LUA_ERRRUN, NULL, NULL);
			else
				infostream << script_get_backtrace(L) << std::endl;
		}
	}
}


code:
/*
Minetest
Copyright (C) 2013 celeron55, Perttu Ahola <celeron55@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.
*/

/******************************************************************************/
/******************************************************************************/
/* WARNING!!!! do NOT add this header in any include file or any code file    */
/*             not being a modapi file!!!!!!!!                                */
/******************************************************************************/
/******************************************************************************/

#ifndef C_INTERNAL_H_
#define C_INTERNAL_H_

extern "C" {
#include <lua.h>
#include <lauxlib.h>
}

#include "common/c_types.h"

/*
	Define our custom indices into the Lua registry table.

	Lua 5.2 and above define the LUA_RIDX_LAST macro. Only numbers above that
	may be used for custom indices, anything else is reserved.

	Lua 5.1 / LuaJIT do not use any numeric indices (only string indices),
	so we can use numeric indices freely.
*/
#ifdef LUA_RIDX_LAST
#define CUSTOM_RIDX_BASE ((LUA_RIDX_LAST)+1)
#else
#define CUSTOM_RIDX_BASE 1
#endif

#define CUSTOM_RIDX_SCRIPTAPI           (CUSTOM_RIDX_BASE)
#define CUSTOM_RIDX_GLOBALS_BACKUP      (CUSTOM_RIDX_BASE + 1)
#define CUSTOM_RIDX_CURRENT_MOD_NAME    (CUSTOM_RIDX_BASE + 2)
#define CUSTOM_RIDX_ERROR_HANDLER       (CUSTOM_RIDX_BASE + 3)

// Pushes the error handler onto the stack and returns its index
#define PUSH_ERROR_HANDLER(L) \
	(lua_rawgeti((L), LUA_REGISTRYINDEX, CUSTOM_RIDX_ERROR_HANDLER), lua_gettop((L)))

#define PCALL_RESL(L, RES) do {                         \
	int result_ = (RES);                                \
	if (result_ != 0) {                                 \
		script_error((L), result_, NULL, __FUNCTION__); \
	}                                                   \
} while (0)

#define script_run_callbacks(L, nargs, mode) \
	script_run_callbacks_f((L), (nargs), (mode), __FUNCTION__)

// What script_run_callbacks does with the return values of callbacks.
// Regardless of the mode, if only one callback is defined,
// its return value is the total return value.
// Modes only affect the case where 0 or >= 2 callbacks are defined.
enum RunCallbacksMode
{
	// Returns the return value of the first callback
	// Returns nil if list of callbacks is empty
	RUN_CALLBACKS_MODE_FIRST,
	// Returns the return value of the last callback
	// Returns nil if list of callbacks is empty
	RUN_CALLBACKS_MODE_LAST,
	// If any callback returns a false value, the first such is returned
	// Otherwise, the first callback's return value (trueish) is returned
	// Returns true if list of callbacks is empty
	RUN_CALLBACKS_MODE_AND,
	// Like above, but stops calling callbacks (short circuit)
	// after seeing the first false value
	RUN_CALLBACKS_MODE_AND_SC,
	// If any callback returns a true value, the first such is returned
	// Otherwise, the first callback's return value (falseish) is returned
	// Returns false if list of callbacks is empty
	RUN_CALLBACKS_MODE_OR,
	// Like above, but stops calling callbacks (short circuit)
	// after seeing the first true value
	RUN_CALLBACKS_MODE_OR_SC,
	// Note: "a true value" and "a false value" refer to values that
	// are converted by lua_toboolean to true or false, respectively.
};

std::string script_get_backtrace(lua_State *L);
int script_error_handler(lua_State *L);
int script_exception_wrapper(lua_State *L, lua_CFunction f);
void script_error(lua_State *L, int pcall_result, const char *mod, const char *fxn);
void script_run_callbacks_f(lua_State *L, int nargs,
	RunCallbacksMode mode, const char *fxn);
void log_deprecated(lua_State *L, const std::string &message);

#endif /* C_INTERNAL_H_ */


code:
/*
Minetest
Copyright (C) 2013 celeron55, Perttu Ahola <celeron55@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.
*/

#include <iostream>

#include "common/c_types.h"
#include "common/c_internal.h"
#include "itemdef.h"

struct EnumString es_ItemType[] =
	{
		{ITEM_NONE, "none"},
		{ITEM_NODE, "node"},
		{ITEM_CRAFT, "craft"},
		{ITEM_TOOL, "tool"},
		{0, NULL},
	};


code:
/*
Minetest
Copyright (C) 2013 celeron55, Perttu Ahola <celeron55@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 C_TYPES_H_
#define C_TYPES_H_

extern "C" {
#include "lua.h"
}

#include <iostream>

#include "exceptions.h"

struct EnumString
{
	int num;
	const char *str;
};

class StackUnroller
{
private:
	lua_State *m_lua;
	int m_original_top;
public:
	StackUnroller(lua_State *L):
		m_lua(L),
		m_original_top(-1)
	{
		m_original_top = lua_gettop(m_lua); // store stack height
	}
	~StackUnroller()
	{
		lua_settop(m_lua, m_original_top); // restore stack height
	}
};

class LuaError : public ModError
{
public:
	LuaError(const std::string &s) : ModError(s) {}
};

extern EnumString es_ItemType[];

#endif /* C_TYPES_H_ */


code:
set(common_SCRIPT_CPP_API_SRCS
	${CMAKE_CURRENT_SOURCE_DIR}/s_async.cpp
	${CMAKE_CURRENT_SOURCE_DIR}/s_base.cpp
	${CMAKE_CURRENT_SOURCE_DIR}/s_entity.cpp
	${CMAKE_CURRENT_SOURCE_DIR}/s_env.cpp
	${CMAKE_CURRENT_SOURCE_DIR}/s_inventory.cpp
	${CMAKE_CURRENT_SOURCE_DIR}/s_item.cpp
	${CMAKE_CURRENT_SOURCE_DIR}/s_node.cpp
	${CMAKE_CURRENT_SOURCE_DIR}/s_nodemeta.cpp
	${CMAKE_CURRENT_SOURCE_DIR}/s_player.cpp
	${CMAKE_CURRENT_SOURCE_DIR}/s_security.cpp
	${CMAKE_CURRENT_SOURCE_DIR}/s_server.cpp
	PARENT_SCOPE)

set(client_SCRIPT_CPP_API_SRCS
	${CMAKE_CURRENT_SOURCE_DIR}/s_client.cpp
	${CMAKE_CURRENT_SOURCE_DIR}/s_mainmenu.cpp
	PARENT_SCOPE)