C++ LuaError函数代码示例

// register_item_raw({lots of stuff})
int ModApiItemMod::l_register_item_raw(lua_State *L)
{
	NO_MAP_LOCK_REQUIRED;
	luaL_checktype(L, 1, LUA_TTABLE);
	int table = 1;

	// Get the writable item and node definition managers from the server
	IWritableItemDefManager *idef =
			getServer(L)->getWritableItemDefManager();
	IWritableNodeDefManager *ndef =
			getServer(L)->getWritableNodeDefManager();

	// Check if name is defined
	std::string name;
	lua_getfield(L, table, "name");
	if(lua_isstring(L, -1)){
		name = lua_tostring(L, -1);
		verbosestream<<"register_item_raw: "<<name<<std::endl;
	} else {
		throw LuaError("register_item_raw: name is not defined or not a string");
	}

	// Check if on_use is defined

	ItemDefinition def;
	// Set a distinctive default value to check if this is set
	def.node_placement_prediction = "__default";

	// Read the item definition
	def = read_item_definition(L, table, def);

	// Default to having client-side placement prediction for nodes
	// ("" in item definition sets it off)
	if(def.node_placement_prediction == "__default"){
		if(def.type == ITEM_NODE)
			def.node_placement_prediction = name;
		else
			def.node_placement_prediction = "";
	}

	// Register item definition
	idef->registerItem(def);

	// Read the node definition (content features) and register it
	if(def.type == ITEM_NODE){
		const ContentFeatures &f = read_content_features(L, table);
		content_t id = ndef->set(f.name, f);

		if(id > MAX_REGISTERED_CONTENT){
			throw LuaError("Number of registerable nodes ("
					+ itos(MAX_REGISTERED_CONTENT+1)
					+ ") exceeded (" + name + ")");
		}
	}

	return 0; /* number of results */
}

/**
**  Parse the Condition for spell.
**
**  @param l         Lua state.
**  @param autocast  pointer to autocast to fill with data.
**
**  @note: autocast must be allocated. All data already in is LOST.
*/
static void CclSpellAutocast(lua_State *l, AutoCastInfo *autocast)
{
	if (!lua_istable(l, -1)) {
		LuaError(l, "incorrect argument");
	}
	const int args = lua_rawlen(l, -1);
	for (int j = 0; j < args; ++j) {
		const char *value = LuaToString(l, -1, j + 1);
		++j;
		if (!strcmp(value, "range")) {
			autocast->Range = LuaToNumber(l, -1, j + 1);
		} else if (!strcmp(value, "min-range")) {
			autocast->MinRange = LuaToNumber(l, -1, j + 1);
		} else if (!strcmp(value, "position-autocast")) {
			lua_rawgeti(l, -1, j + 1);
			autocast->PositionAutoCast = new LuaCallback(l, -1);
			lua_pop(l, 1);
		} else if (!strcmp(value, "combat")) {
			autocast->Combat = Ccl2Condition(l, LuaToString(l, -1, j + 1));
		} else if (!strcmp(value, "attacker")) {
			autocast->Attacker = Ccl2Condition(l, LuaToString(l, -1, j + 1));
		} else if (!strcmp(value, "corpse")) {
			autocast->Corpse = Ccl2Condition(l, LuaToString(l, -1, j + 1));
		} else if (!strcmp(value, "priority")) {
			lua_rawgeti(l, -1, j + 1);
			if (!lua_istable(l, -1) || lua_rawlen(l, -1) != 2) {
				LuaError(l, "incorrect argument");
			}
			lua_rawgeti(l, -1, 1);
			std::string var = LuaToString(l, -1);
			int index = UnitTypeVar.VariableNameLookup[var.c_str()];// User variables
			if (index == -1) {
				if (!strcmp(var.c_str(), "Distance")) {
					index = ACP_DISTANCE;
				} else {
					fprintf(stderr, "Bad variable name '%s'\n", var.c_str());
					Exit(1);
				}
			}
			autocast->PriorytyVar = index;
			lua_pop(l, 1);
			autocast->ReverseSort = LuaToBoolean(l, -1, 2);

			lua_pop(l, 1);
		} else if (!strcmp(value, "condition")) {
			if (!autocast->Condition) {
				autocast->Condition = new ConditionInfo;
			}
			lua_rawgeti(l, -1, j + 1);
			CclSpellCondition(l, autocast->Condition);
			lua_pop(l, 1);
		} else {
			LuaError(l, "Unsupported autocast tag: %s" _C_ value);
		}
	}
}

/**
**  Get world data.
**
**  @param l  Lua state.
*/
static int CclGetWorldData(lua_State *l)
{
	if (lua_gettop(l) < 2) {
		LuaError(l, "incorrect argument");
	}
	std::string world_ident = LuaToString(l, 1);
	CWorld *world = CWorld::GetWorld(world_ident);
	if (!world) {
		LuaError(l, "World \"%s\" doesn't exist." _C_ world_ident.c_str());
	}
	const char *data = LuaToString(l, 2);

	if (!strcmp(data, "Name")) {
		lua_pushstring(l, world->Name.c_str());
		return 1;
	} else if (!strcmp(data, "ID")) {
		lua_pushnumber(l, world->ID);
		return 1;
	} else if (!strcmp(data, "Description")) {
		lua_pushstring(l, world->Description.c_str());
		return 1;
	} else if (!strcmp(data, "Background")) {
		lua_pushstring(l, world->Background.c_str());
		return 1;
	} else if (!strcmp(data, "Quote")) {
		lua_pushstring(l, world->Quote.c_str());
		return 1;
	} else if (!strcmp(data, "Plane")) {
		if (world->Plane) {
			lua_pushstring(l, world->Plane->Ident.c_str());
		} else {
			lua_pushstring(l, "");
		}
		return 1;
	} else if (!strcmp(data, "Provinces")) {
		lua_createtable(l, world->Provinces.size(), 0);
		for (size_t i = 1; i <= world->Provinces.size(); ++i)
		{
			lua_pushstring(l, world->Provinces[i-1]->Name.c_str());
			lua_rawseti(l, -2, i);
		}
		return 1;
	} else if (!strcmp(data, "Species")) {
		lua_createtable(l, world->Species.size(), 0);
		for (size_t i = 1; i <= world->Species.size(); ++i)
		{
			lua_pushstring(l, world->Species[i-1]->Ident.c_str());
			lua_rawseti(l, -2, i);
		}
		return 1;
	} else {
		LuaError(l, "Invalid field: %s" _C_ data);
	}

	return 0;
}

/**
**  Create a missile on the map
**
**  @param l  Lua state.
**
*/
static int CclCreateMissile(lua_State *l)
{
	LuaCheckArgs(l, 6);

	const std::string name = LuaToString(l, 1);
	const MissileType *mtype = MissileTypeByIdent(name);
	if (!mtype) {
		LuaError(l, "Bad missile");
	}
	PixelPos startpos, endpos;
	if (!lua_istable(l, 2) || lua_rawlen(l, 2) != 2) {
		LuaError(l, "incorrect argument !!");
	}
	lua_rawgeti(l, 2, 1);
	startpos.x = LuaToNumber(l, -1);
	lua_pop(l, 1);
	lua_rawgeti(l, 2, 2);
	startpos.y = LuaToNumber(l, -1);
	lua_pop(l, 1);
	if (!lua_istable(l, 3) || lua_rawlen(l, 3) != 2) {
		LuaError(l, "incorrect argument !!");
	}
	lua_rawgeti(l, 3, 1);
	endpos.x = LuaToNumber(l, -1);
	lua_pop(l, 1);
	lua_rawgeti(l, 3, 2);
	endpos.y = LuaToNumber(l, -1);
	lua_pop(l, 1);

	const int sourceUnitId = LuaToNumber(l, 4);
	const int destUnitId = LuaToNumber(l, 5);
	const bool dealDamage = LuaToBoolean(l, 6);
	CUnit *sourceUnit = sourceUnitId != -1 ? &UnitManager.GetSlotUnit(sourceUnitId) : NULL;
	CUnit *destUnit = destUnitId != -1 ? &UnitManager.GetSlotUnit(destUnitId) : NULL;

	if (sourceUnit != NULL) {
		startpos += sourceUnit->GetMapPixelPosTopLeft();
	}
	if (destUnit != NULL) {
		endpos += destUnit->GetMapPixelPosTopLeft();
	}

	Missile *missile = MakeMissile(*mtype, startpos, endpos);
	if (!missile) {
		return 0;
	}
	if (dealDamage) {
		missile->SourceUnit = sourceUnit;
	}
	missile->TargetUnit = destUnit;
	return 0;
}

void CMapField::parse(lua_State *l)
{
	if (!lua_istable(l, -1)) {
		LuaError(l, "incorrect argument");
	}
	const int len = lua_rawlen(l, -1);
	if (len < 4) {
		LuaError(l, "incorrect argument");
	}

	this->tile = LuaToNumber(l, -1, 1);
	this->playerInfo.SeenTile = LuaToNumber(l, -1, 2);
	this->Value = LuaToNumber(l, -1, 3);
	this->cost = LuaToNumber(l, -1, 4);

	for (int j = 4; j < len; ++j) {
		const char *value = LuaToString(l, -1, j + 1);

		if (!strcmp(value, "explored")) {
			++j;
			this->playerInfo.Visible[LuaToNumber(l, -1, j + 1)] = 1;
		} else if (!strcmp(value, "human")) {
			this->Flags |= MapFieldHuman;
		} else if (!strcmp(value, "land")) {
			this->Flags |= MapFieldLandAllowed;
		} else if (!strcmp(value, "coast")) {
			this->Flags |= MapFieldCoastAllowed;
		} else if (!strcmp(value, "water")) {
			this->Flags |= MapFieldWaterAllowed;
		} else if (!strcmp(value, "mud")) {
			this->Flags |= MapFieldNoBuilding;
		} else if (!strcmp(value, "block")) {
			this->Flags |= MapFieldUnpassable;
		} else if (!strcmp(value, "wall")) {
			this->Flags |= MapFieldWall;
		} else if (!strcmp(value, "rock")) {
			this->Flags |= MapFieldRocks;
		} else if (!strcmp(value, "wood")) {
			this->Flags |= MapFieldForest;
		} else if (!strcmp(value, "ground")) {
			this->Flags |= MapFieldLandUnit;
		} else if (!strcmp(value, "air")) {
			this->Flags |= MapFieldAirUnit;
		} else if (!strcmp(value, "sea")) {
			this->Flags |= MapFieldSeaUnit;
		} else if (!strcmp(value, "building")) {
			this->Flags |= MapFieldBuilding;
		} else {
			LuaError(l, "Unsupported tag: %s" _C_ value);
		}
	}
}

void LuaWear_Event(const LLUUID& assetid)
{
	LLWearable *wear=LuaLoadWearable(assetid);
	if(!wear)
		LuaError("No Wearable found");
	else if((wear=gWearableList.createCopy(wear))==NULL)
		LuaError("Failed creation of new wearable");
	else
	{
		wear->saveNewAsset();
		wear->writeToAvatar(false);
	}
}

/**
**  Parse the missile location description for a spell action.
**
**  @param l         Lua state.
**  @param location  Pointer to missile location description.
**
**  @note This is only here to avoid code duplication. You don't have
**        any reason to USE this:)
*/
static void CclSpellMissileLocation(lua_State *l, SpellActionMissileLocation *location)
{
	const char *value;
	int args;
	int j;

	Assert(location != NULL);

	if (!lua_istable(l, -1)) {
		LuaError(l, "incorrect argument");
	}
	args = lua_objlen(l, -1);
	j = 0;

	for (j = 0; j < args; ++j) {
		lua_rawgeti(l, -1, j + 1);
		value = LuaToString(l, -1);
		lua_pop(l, 1);
		++j;
		if (!strcmp(value, "base")) {
			lua_rawgeti(l, -1, j + 1);
			value = LuaToString(l, -1);
			lua_pop(l, 1);
			if (!strcmp(value, "caster")) {
				location->Base = LocBaseCaster;
			} else if (!strcmp(value, "target")) {
				location->Base = LocBaseTarget;
			} else {
				LuaError(l, "Unsupported missile location base flag: %s" _C_ value);
			}
		} else if (!strcmp(value, "add-x")) {
			lua_rawgeti(l, -1, j + 1);
			location->AddX = LuaToNumber(l, -1);
			lua_pop(l, 1);
		} else if (!strcmp(value, "add-y")) {
			lua_rawgeti(l, -1, j + 1);
			location->AddY = LuaToNumber(l, -1);
			lua_pop(l, 1);
		} else if (!strcmp(value, "add-rand-x")) {
			lua_rawgeti(l, -1, j + 1);
			location->AddRandX = LuaToNumber(l, -1);
			lua_pop(l, 1);
		} else if (!strcmp(value, "add-rand-y")) {
			lua_rawgeti(l, -1, j + 1);
			location->AddRandY = LuaToNumber(l, -1);
			lua_pop(l, 1);
		} else {
			LuaError(l, "Unsupported missile location description flag: %s" _C_ value);
		}
	}
}

/**
**  Define race names
**
**  @param l  Lua state.
*/
static int CclDefineRaceNames(lua_State *l)
{
	int i;
	int j;
	int k;
	int args;
	int subargs;
	const char *value;

	PlayerRaces.Count = 0;
	args = lua_gettop(l);
	for (j = 0; j < args; ++j) {
		value = LuaToString(l, j + 1);
		if (!strcmp(value, "race")) {
			++j;
			if (!lua_istable(l, j + 1)) {
				LuaError(l, "incorrect argument");
			}
			subargs = luaL_getn(l, j + 1);
			i = PlayerRaces.Count++;
			PlayerRaces.Name[i] = NULL;
			PlayerRaces.Display[i] = NULL;
			PlayerRaces.Visible[i] = 0;
			for (k = 0; k < subargs; ++k) {
				lua_rawgeti(l, j + 1, k + 1);
				value = LuaToString(l, -1);
				lua_pop(l, 1);
				if (!strcmp(value, "name")) {
					++k;
					lua_rawgeti(l, j + 1, k + 1);
					PlayerRaces.Name[i] = new_strdup(LuaToString(l, -1));
					lua_pop(l, 1);
				} else if (!strcmp(value, "display")) {
					++k;
					lua_rawgeti(l, j + 1, k + 1);
					PlayerRaces.Display[i] = new_strdup(LuaToString(l, -1));
					lua_pop(l, 1);
				} else if (!strcmp(value, "visible")) {
					PlayerRaces.Visible[i] = 1;
				} else {
					LuaError(l, "Unsupported tag: %s" _C_ value);
				}
			}
		} else {
			LuaError(l, "Unsupported tag: %s" _C_ value);
		}
	}

	return 0;
}

// Return number of accepted items to be taken
int ScriptApiDetached::detached_inventory_AllowTake(
		const std::string &name,
		const std::string &listname, int index, ItemStack &stack,
		ServerActiveObject *player)
{
	SCRIPTAPI_PRECHECKHEADER

	int error_handler = PUSH_ERROR_HANDLER(L);

	// Push callback function on stack
	if (!getDetachedInventoryCallback(name, "allow_take"))
		return stack.count; // All will be accepted

	// Call function(inv, listname, index, stack, player)
	InventoryLocation loc;
	loc.setDetached(name);
	InvRef::create(L, loc);              // inv
	lua_pushstring(L, listname.c_str()); // listname
	lua_pushinteger(L, index + 1);       // index
	LuaItemStack::create(L, stack);      // stack
	objectrefGetOrCreate(L, player);     // player
	PCALL_RES(lua_pcall(L, 5, 1, error_handler));
	if (!lua_isnumber(L, -1))
		throw LuaError("allow_take should return a number. name=" + name);
	int ret = luaL_checkinteger(L, -1);
	lua_pop(L, 2); // Pop integer and error handler
	return ret;
}

/**
**  Create a sound.
**
**  Glue between c and scheme. This function asks the sound system to
**  register a sound under a given name, wiht an associated list of files
**  (the list can be replaced by only one file).
**
**  @param l  Lua state.
**
**  @return   the sound id of the created sound
*/
static int CclMakeSound(lua_State *l)
{
	LuaCheckArgs(l, 2);

	std::string c_name = LuaToString(l, 1);
	std::vector<std::string> files;
	CSound *id;
	if (lua_isstring(l, 2)) {
		// only one file
		files.push_back(LuaToString(l, 2));
		id = MakeSound(c_name, files);
	} else if (lua_istable(l, 2)) {
		// several files
		const int args = lua_rawlen(l, 2);
		files.reserve(args);
		for (int j = 0; j < args; ++j) {
			lua_rawgeti(l, 2, j + 1);
			files.push_back(LuaToString(l, -1));
			lua_pop(l, 1);
		}
		id = MakeSound(c_name, files);
	} else {
		LuaError(l, "string or table expected");
		return 0;
	}
	LuaUserData *data = (LuaUserData *)lua_newuserdata(l, sizeof(LuaUserData));
	data->Type = LuaSoundType;
	data->Data = id;
	return 1;
}

/**
**  Get a player's units in rectangle box specified with 2 coordinates
**
**  @param l  Lua state.
**
**  @return   Array of units.
*/
static int CclGetUnitsAroundUnit(lua_State *l)
{
	const int nargs = lua_gettop(l);
	if (nargs != 2 && nargs != 3) {
		LuaError(l, "incorrect argument\n");
	}

	const int slot = LuaToNumber(l, 1);
	const CUnit &unit = UnitManager.GetSlotUnit(slot);
	const int range = LuaToNumber(l, 2);
	bool allUnits = false;
	if (nargs == 3) {
		allUnits = LuaToBoolean(l, 3);
	}
	lua_newtable(l);
	std::vector<CUnit *> table;
	if (allUnits) {
		SelectAroundUnit(unit, range, table, HasNotSamePlayerAs(Players[PlayerNumNeutral]));
	} else {
		SelectAroundUnit(unit, range, table, HasSamePlayerAs(*unit.Player));
	}
	size_t n = 0;
	for (size_t i = 0; i < table.size(); ++i) {
		if (table[i]->IsAliveOnMap()) {
			lua_pushnumber(l, UnitNumber(*table[i]));
			lua_rawseti(l, -2, ++n);
		}
	}
	return 1;
}

// Return number of accepted items to be put
int ScriptApiNodemeta::nodemeta_inventory_AllowPut(v3s16 p,
		const std::string &listname, int index, ItemStack &stack,
		ServerActiveObject *player)
{
	SCRIPTAPI_PRECHECKHEADER

	INodeDefManager *ndef = getServer()->ndef();

	// If node doesn't exist, we don't know what callback to call
	MapNode node = getEnv()->getMap().getNodeNoEx(p);
	if (node.getContent() == CONTENT_IGNORE)
		return 0;

	// Push callback function on stack
	std::string nodename = ndef->get(node).name;
	if (!getItemCallback(nodename.c_str(), "allow_metadata_inventory_put"))
		return stack.count;

	// Call function(pos, listname, index, stack, player)
	push_v3s16(L, p);                    // pos
	lua_pushstring(L, listname.c_str()); // listname
	lua_pushinteger(L, index + 1);       // index
	LuaItemStack::create(L, stack);      // stack
	objectrefGetOrCreate(L, player);     // player
	if (lua_pcall(L, 5, 1, m_errorhandler))
		scriptError();
	if(!lua_isnumber(L, -1))
		throw LuaError("allow_metadata_inventory_put should"
				" return a number, guilty node: " + nodename);
	int num = luaL_checkinteger(L, -1);
	lua_pop(L, 1); // Pop integer
	return num;
}

/**
**  Parse an animation
*/
static CAnimation *ParseAnimation(lua_State *l, int idx)
{
	if (!lua_istable(l, idx)) {
		LuaError(l, "incorrect argument");
	}
	const int args = lua_rawlen(l, idx);

	if (args == 0) {
		return NULL;
	}
	Labels.clear();
	LabelsLater.clear();

	const char *str = LuaToString(l, idx, 1);

	CAnimation *firstAnim = ParseAnimationFrame(l, str);
	CAnimation *prev = firstAnim;
	for (int j = 1; j < args; ++j) {
		const char *str = LuaToString(l, idx, j + 1);
		CAnimation *anim = ParseAnimationFrame(l, str);
		prev->Next = anim;
		prev = anim;
	}
	prev->Next = firstAnim;
	FixLabels(l);
	return firstAnim;
}

int LuaVoxelManip::l_set_lighting(lua_State *L)
{
	NO_MAP_LOCK_REQUIRED;

	LuaVoxelManip *o = checkobject(L, 1);
	if (!o->is_mapgen_vm)
		return 0;

	if (!lua_istable(L, 2))
		return 0;

	u8 light;
	light  = (getintfield_default(L, 2, "day",   0) & 0x0F);
	light |= (getintfield_default(L, 2, "night", 0) & 0x0F) << 4;

	MMVManip *vm = o->vm;

	v3s16 yblock = v3s16(0, 1, 0) * MAP_BLOCKSIZE;
	v3s16 pmin = lua_istable(L, 3) ? check_v3s16(L, 3) : vm->m_area.MinEdge + yblock;
	v3s16 pmax = lua_istable(L, 4) ? check_v3s16(L, 4) : vm->m_area.MaxEdge - yblock;

	sortBoxVerticies(pmin, pmax);
	if (!vm->m_area.contains(VoxelArea(pmin, pmax)))
		throw LuaError("Specified voxel area out of VoxelManipulator bounds");

	Mapgen mg;
	mg.vm = vm;

	mg.setLighting(light, pmin, pmax);

	return 0;
}

/**
**  Define burning building missiles.
**
**  @param l  Lua state.
*/
static int CclDefineBurningBuilding(lua_State *l)
{
	for (std::vector<BurningBuildingFrame *>::iterator i = BurningBuildingFrames.begin();
		 i != BurningBuildingFrames.end(); ++i) {
		delete *i;
	}
	BurningBuildingFrames.clear();

	const int args = lua_gettop(l);
	for (int j = 0; j < args; ++j) {
		if (!lua_istable(l, j + 1)) {
			LuaError(l, "incorrect argument");
		}
		BurningBuildingFrame *ptr = new BurningBuildingFrame;
		const int subargs = lua_rawlen(l, j + 1);

		for (int k = 0; k < subargs; ++k) {
			const char *value = LuaToString(l, j + 1, k + 1);
			++k;

			if (!strcmp(value, "percent")) {
				ptr->Percent = LuaToNumber(l, j + 1, k + 1);
			} else if (!strcmp(value, "missile")) {
				ptr->Missile = MissileTypeByIdent(LuaToString(l, j + 1, k + 1));
			}
		}
		BurningBuildingFrames.insert(BurningBuildingFrames.begin(), ptr);
	}
	return 0;
}