client: Packet handling in Lua; extensions/cereal

client/packet.lua

@@ -1,18 +1,25 @@
 local log = buildat.Logger("__client/packet")
 
-__buildat_packet_subs = {}
+local packet_subs = {}
 
-function buildat:sub_packet(name, cb)
-	__buildat_packet_subs[name] = cb
+function __buildat_handle_packet(name, data)
+	local cb = packet_subs[name]
+	if cb then
+		cb(data)
+	end
 end
-function buildat:unsub_packet(cb)
+
+function buildat.sub_packet(name, cb)
+	packet_subs[name] = cb
+end
+function buildat.unsub_packet(cb)
 	for name, cb1 in pairs(buildat.packet_subs) do
 		if cb1 == cb then
-			__buildat_packet_subs[cb] = nil
+			packet_subs[cb] = nil
 		end
 	end
 end
 
-function buildat:send_packet(name, data)
+function buildat.send_packet(name, data)
 	__buildat_send_packet(name, data)
 end

extensions/cereal/init.lua

@@ -0,0 +1,11 @@
+-- Buildat: extension/cereal/init.lua
+local polybox = require("buildat/extension/polycode_sandbox")
+local log = buildat.Logger("extension/cereal")
+local M = {safe = {}}
+
+function M.safe.binary_input(data, types)
+	return __buildat_cereal_binary_input(data, types)
+end
+
+return M
+

src/client/app.cpp

@@ -12,6 +12,8 @@
 #include <OSBasics.h>
 #pragma GCC diagnostic pop
 #include <c55/getopt.h>
+#include <cereal/archives/portable_binary.hpp>
+#include <cereal/types/string.hpp>
 #include <core/log.h>
 #include <signal.h>
 #define MODULE "__main"
@@ -283,6 +285,7 @@ struct CApp: public Polycode::EventHandler, public App
 		DEF_BUILDAT_FUNC(get_file_path)
 		DEF_BUILDAT_FUNC(get_path)
 		DEF_BUILDAT_FUNC(pcall)
+		DEF_BUILDAT_FUNC(cereal_binary_input)
 
 		ss_ init_lua_path = g_client_config.share_path+"/client/init.lua";
 		int error = luaL_dofile(L, init_lua_path.c_str());
@@ -332,6 +335,16 @@ struct CApp: public Polycode::EventHandler, public App
 		}
 	}
 
+	void handle_packet(const ss_ &name, const ss_ &data)
+	{
+		log_v(MODULE, "handle_packet(): %s", cs(name));
+
+		lua_getfield(L, LUA_GLOBALSINDEX, "__buildat_handle_packet");
+		lua_pushlstring(L, name.c_str(), name.size());
+		lua_pushlstring(L, data.c_str(), data.size());
+		lua_call(L, 2, 0);
+	}
+
 	// Non-public methods
 
 	// send_packet(name: string, data: string)
@@ -474,6 +487,66 @@ struct CApp: public Polycode::EventHandler, public App
 		lua_pushvalue(L, error_stack_i);
 		return 2;
 	}
+
+	// cereal_binary_input(data: string, types: table of strings)
+	// -> table of values
+	static int l_cereal_binary_input(lua_State *L)
+	{
+		size_t data_len = 0;
+		const char *data_c = lua_tolstring(L, 1, &data_len);
+		ss_ data(data_c, data_len);
+
+		int types_table_L = 2;
+
+		lua_newtable(L);
+		int result_table_L = lua_gettop(L);
+
+		std::istringstream is(data, std::ios::binary);
+		{
+			cereal::PortableBinaryInputArchive ar(is);
+
+			int output_index = 1;
+			lua_pushnil(L);
+			while(lua_next(L, types_table_L) != 0)
+			{
+				ss_ type = lua_tostring(L, -1);
+				lua_pop(L, 1);
+				log_t(MODULE, "type=%s", cs(type));
+				if(type == "byte"){
+					uchar b;
+					ar(b);
+					lua_pushinteger(L, b);
+					lua_rawseti(L, result_table_L, output_index++);
+					continue;
+				}
+				if(type == "int32"){
+					int32_t i;
+					ar(i);
+					lua_pushinteger(L, i);
+					lua_rawseti(L, result_table_L, output_index++);
+					continue;
+				}
+				if(type == "double"){
+					double d;
+					ar(d);
+					lua_pushnumber(L, d);
+					lua_rawseti(L, result_table_L, output_index++);
+					continue;
+				}
+				if(type == "string"){
+					ss_ s;
+					ar(s);
+					lua_pushlstring(L, s.c_str(), s.size());
+					lua_rawseti(L, result_table_L, output_index++);
+					continue;
+				}
+				throw Exception(ss_()+"Unknown type \""+type+"\""
+						"; known types are byte, int32, double, string");
+			}
+		}
+		// Result table is on top of stack
+		return 1;
+	}
 };
 
 App* createApp(Polycode::PolycodeView *view)

src/client/app.h

@@ -19,6 +19,7 @@ namespace app
 		virtual bool update() = 0;
 		virtual void shutdown() = 0;
 		virtual void run_script(const ss_ &script) = 0;
+		virtual void handle_packet(const ss_ &name, const ss_ &data) = 0;
 	};
 
 	App* createApp(Polycode::PolycodeView *view);

src/client/state.cpp

@@ -133,6 +133,11 @@ struct CState: public State
 
 	void handle_packet(const ss_ &packet_name, const ss_ &data)
 	{
+		if(packet_name.substr(0,5) != "core:"){
+			m_app->handle_packet(packet_name, data);
+			return;
+		}
+
 		if(packet_name == "core:run_script"){
 			log_i(MODULE, "Asked to run script:\n----\n%s\n----", cs(data));
 			if(m_app)

test/testmodules/test1/client_lua/init.lua

@@ -1,17 +1,9 @@
 -- Buildat: test1/client_lua/init.lua
 local log = buildat.Logger("test1")
+local dump = buildat.dump
 log:info("test1/init.lua loaded")
 
---[[
--- Temporary test
-require "Polycode/Core"
-scene = Scene(Scene.SCENE_2D)
-scene:getActiveCamera():setOrthoSize(640, 480)
-label = SceneLabel("Hello from remote module!", 32)
-label:setPosition(0, -100, 0)
-scene:addChild(label)
---]]
-
+-- Test extension interface safety
 local test = require("buildat/extension/test")
 
 test.f()
@@ -24,10 +16,35 @@ ground = g3d.ScenePrimitive(g3d.ScenePrimitive.TYPE_PLANE, 5,5)
 ground:loadTexture("test1/green_texture.png")
 scene:addEntity(ground)
 
-box =  g3d.ScenePrimitive(g3d.ScenePrimitive.TYPE_BOX, 1,1,1)
-box:loadTexture("test1/pink_texture.png")
-box:setPosition(0.0, 0.5, 0.0)
-scene:addEntity(box)
-
 scene:getDefaultCamera():setPosition(7,7,7)
 scene:getDefaultCamera():lookAt(g3d.Vector3(0,0,0), g3d.Vector3(0,1,0))
+
+local cereal = require("buildat/extension/cereal")
+
+buildat.sub_packet("test1:add_box", function(data)
+	values = cereal.binary_input(data, {
+		"double", "double", "double",
+		"double", "double", "double"
+	})
+	local w = values[1]
+	local h = values[2]
+	local d = values[3]
+	local x = values[4]
+	local y = values[5]
+	local z = values[6]
+	log:info("values="..dump(values))
+	box = g3d.ScenePrimitive(g3d.ScenePrimitive.TYPE_BOX, w,h,d)
+	box:loadTexture("test1/pink_texture.png")
+	box:setPosition(x, y, z)
+	scene:addEntity(box)
+end)
+
+--[[
+-- Temporary test
+require "Polycode/Core"
+scene = Scene(Scene.SCENE_2D)
+scene:getActiveCamera():setOrthoSize(640, 480)
+label = SceneLabel("Hello from remote module!", 32)
+label:setPosition(0, -100, 0)
+scene:addChild(label)
+--]]

test/testmodules/test1/test1.cpp

@@ -2,10 +2,10 @@
 #include "interface/server.h"
 #include "interface/event.h"
 #include "test1/api.h"
-//#include "client_lua/api.h"
 #include "client_file/api.h"
 #include "network/api.h"
 #include "core/log.h"
+#include <cereal/archives/portable_binary.hpp>
 
 using interface::Event;
 
@@ -71,10 +71,21 @@ struct Module: public interface::Module
 	void on_files_transmitted(const client_file::FilesTransmitted &event)
 	{
 		log_v(MODULE, "on_files_transmitted(): recipient=%zu", event.recipient);
+
 		network::access(m_server, [&](network::Interface * inetwork){
 			inetwork->send(event.recipient, "core:run_script",
 					"buildat:run_script_file(\"test1/init.lua\")");
 		});
+
+		network::access(m_server, [&](network::Interface * inetwork){
+			std::ostringstream os(std::ios::binary);
+			{
+				cereal::PortableBinaryOutputArchive ar(os);
+				ar(1.0, 1.0, 1.0);
+				ar(0.0, 0.5, 0.0);
+			}
+			inetwork->send(event.recipient, "test1:add_box", os.str());
+		});
 	}
 
 	void on_packet_received(const network::Packet &packet)