net.server_event: Initial commit of server_event.lua. Don't get too excited, it's not used at all yet, and is still incomplete :)

1 files changed, 759 insertions, 0 deletions

diff --git a/net/server_event.lua b/net/server_event.lua
new file mode 100644
index 00000000..15d1dea0
--- /dev/null
+++ b/net/server_event.lua
@@ -0,0 +1,759 @@
+--[[

+

+

+			server.lua based on lua/libevent by blastbeat

+

+			notes:

+			-- when using luaevent, never register 2 or more EV_READ at one socket, same for EV_WRITE

+			-- you cant even register a new EV_READ/EV_WRITE callback inside another one

+			-- never call eventcallback:close( ) from inside eventcallback

+			-- to do some of the above, use timeout events or something what will called from outside

+			-- dont let garbagecollect eventcallbacks, as long they are running

+			-- when using luasec, there are 4 cases of timeout errors: wantread or wantwrite during reading or writing

+

+--]]

+

+

+local SCRIPT_NAME           = "server_event.lua"

+local SCRIPT_VERSION        = "0.05"

+local SCRIPT_AUTHOR         = "blastbeat"

+local LAST_MODIFIED         = "2009/11/20"

+

+local cfg = {

+	MAX_CONNECTIONS       = 100000,  -- max per server connections (use "ulimit -n" on *nix)

+	MAX_HANDSHAKE_ATTEMPS = 10,  -- attemps to finish ssl handshake

+	HANDSHAKE_TIMEOUT     = 1,  -- timout in seconds per handshake attemp

+	MAX_READ_LENGTH       = 1024 * 1024 * 1024 * 1024,  -- max bytes allowed to read from sockets

+	MAX_SEND_LENGTH       = 1024 * 1024 * 1024 * 1024,  -- max bytes size of write buffer (for writing on sockets)

+	ACCEPT_DELAY          = 10,  -- seconds to wait until the next attemp of a full server to accept

+	READ_TIMEOUT          = 60 * 30,  -- timeout in seconds for read data from socket

+	WRITE_TIMEOUT         = 30,  -- timeout in seconds for write data on socket

+	CONNECT_TIMEOUT       = 10,  -- timeout in seconds for connection attemps

+	CLEAR_DELAY           = 5,  -- seconds to wait for clearing interface list (and calling ondisconnect listeners) 

+	DEBUG                 = true,  -- show debug messages

+}

+

+local function use(x) return rawget(_G, x); end

+local print = use "print"

+local pcall = use "pcall"

+local ipairs = use "ipairs"

+local string = use "string"

+local select = use "select"

+local require = use "require"

+local tostring = use "tostring"

+local coroutine = use "coroutine"

+local setmetatable = use "setmetatable"

+

+local ssl = use "ssl"

+local socket = use "socket"

+

+local log = require ("util.logger").init("socket")

+

+local function debug(...)

+	return log("debug", ("%s "):rep(select('#', ...)), ...)

+end

+

+local bitor = ( function( ) -- thx Rici Lake

+	local hasbit = function( x, p )

+		return x % ( p + p ) >= p

+	end

+	return function( x, y ) 

+		local p = 1

+		local z = 0

+		local limit = x > y and x or y

+		while p <= limit do 

+			if hasbit( x, p ) or hasbit( y, p ) then

+				z = z + p

+			end

+			p = p + p

+		end

+		return z

+	end

+end )( )

+

+local getid = function( )

+	return function( )

+	end

+end

+

+local event = require "luaevent.core"

+local base = event.new( )

+local EV_READ = event.EV_READ

+local EV_WRITE = event.EV_WRITE

+local EV_TIMEOUT = event.EV_TIMEOUT

+

+local EV_READWRITE = bitor( EV_READ, EV_WRITE )

+

+local interfacelist = ( function( )  -- holds the interfaces for sockets

+	local array = { }

+	local len = 0

+	return function( method, arg )

+		if "add" == method then

+			len = len + 1

+			array[ len ] = arg

+			arg:_position( len )

+			return len

+		elseif "delete" == method then

+			if len <= 0 then

+				return nil, "array is already empty"

+			end

+			local position = arg:_position()  -- get position in array

+			if position ~= len then

+				local interface = array[ len ]  -- get last interface

+				array[ position ] = interface  -- copy it into free position

+				array[ len ] = nil  -- free last position

+				interface:_position( position )  -- set new position in array

+			else  -- free last position

+				array[ len ] = nil

+			end

+			len = len - 1

+			return len    

+		else

+			return array

+		end

+	end

+end )( )

+

+-- Client interface methods

+local interface_mt

+do

+	interface_mt = {}; interface_mt.__index = interface_mt;

+	

+	local addevent = base.addevent

+	local coroutine_wrap, coroutine_yield = coroutine.wrap,coroutine.yield

+	local string_len = string.len

+	

+	-- Private methods

+	function interface_mt:_position(new_position)

+			self.position = new_position or self.position

+			return self.position;

+	end

+	function interface_mt:_close() -- regs event to start self:_destroy()

+			local callback = function( )

+				self:_destroy();

+				self.eventclose = nil

+				return -1

+			end

+			self.eventclose = addevent( base, nil, EV_TIMEOUT, callback, 0 )

+			return true

+	end

+	

+	function interface_mt:_start_connection(plainssl) -- should be called from addclient

+			local callback = function( event )

+				if EV_TIMEOUT == event then  -- timout during connection

+					self.fatalerror = "connection timeout"

+					self.listener.ontimeout( self )  -- call timeout listener

+					self:_close()

+					debug( "new connection failed. id:", self, "error:", self.fatalerror )

+				else

+					if plainssl then  -- start ssl session

+						self:_start_ssl( self.listener.onconnect )

+					else  -- normal connection

+						self:_start_session( self.listener.onconnect )

+					end

+					debug( "new connection established. id:", self )

+				end

+				self.eventconnect = nil

+				return -1

+			end

+			self.eventconnect = addevent( base, self.conn, EV_WRITE, callback, cfg.CONNECT_TIMEOUT )

+			return true

+	end

+	function interface_mt:_start_session(onconnect) -- new session, for example after startssl

+		if self.type == "client" then

+			local callback = function( )

+				self:_lock( false,  false, false )

+				--vdebug( "start listening on client socket with id:", self )      

+				self.eventread = addevent( base, self.conn, EV_READ, self.readcallback, cfg.READ_TIMEOUT )  -- register callback

+				onconnect( self )

+				self.eventsession = nil

+				return -1

+			end

+			self.eventsession = addevent( base, nil, EV_TIMEOUT, callback, 0 )

+		else

+			self:_lock( false )

+			--vdebug( "start listening on server socket with id:", self )

+			self.eventread = addevent( base, self.conn, EV_READ, self.readcallback )  -- register callback

+		end

+		return true

+	end

+	function interface_mt:_start_ssl(arg) -- old socket will be destroyed, therefore we have to close read/write events first

+			--vdebug( "starting ssl session with client id:", self )

+			local _

+			_ = self.eventread and self.eventread:close( )  -- close events; this must be called outside of the event callbacks!

+			_ = self.eventwrite and self.eventwrite:close( )

+			self.eventread, self.eventwrite = nil, nil

+			local err

+			self.conn, err = ssl.wrap( self.conn, self.sslctx )

+			if err then

+				self.fatalerror = err

+				self.conn = nil  -- cannot be used anymore

+				if "onconnect" == arg then

+					self.ondisconnect = nil  -- dont call this when client isnt really connected

+				end

+				self:_close()

+				debug( "fatal error while ssl wrapping:", err )

+				return false

+			end

+			self.conn:settimeout( 0 )  -- set non blocking

+			local handshakecallback = coroutine_wrap(

+				function( event )

+					local _, err

+					local attempt = 0

+					local maxattempt = cfg.MAX_HANDSHAKE_ATTEMPS

+					while attempt < 1000 do  -- no endless loop

+						attempt = attempt + 1

+						debug( "ssl handshake of client with id:", self, "attemp:", attempt )

+						if attempt > maxattempt then

+							self.fatalerror = "max handshake attemps exceeded"

+						elseif EV_TIMEOUT == event then

+							self.fatalerror = "timeout during handshake"

+						else

+							_, err = self.conn:dohandshake( )

+							if not err then

+								self:_lock( false, false, false )  -- unlock the interface; sending, closing etc allowed

+								self.send = self.conn.send  -- caching table lookups with new client object

+								self.receive = self.conn.receive

+								local onsomething

+								if "onconnect" == arg then  -- trigger listener

+									onsomething = self.listener.onconnect

+								else

+									onsomething = self.listener.onsslconnection

+								end

+								self:_start_session( onsomething )

+								debug( "ssl handshake done" )

+								self.eventhandshake = nil

+								return -1

+							end

+							debug( "error during ssl handshake:", err )  

+							if err == "wantwrite" then

+								event = EV_WRITE

+							elseif err == "wantread" then

+								event = EV_READ

+							else

+								self.fatalerror = err

+							end            

+						end

+						if self.fatalerror then

+							if "onconnect" == arg then

+								self.ondisconnect = nil  -- dont call this when client isnt really connected

+							end

+							self:_close()

+							debug( "handshake failed because:", self.fatalerror )

+							self.eventhandshake = nil

+							return -1

+						end

+						event = coroutine_yield( event, cfg.HANDSHAKE_TIMEOUT )  -- yield this monster...

+					end

+				end

+			)

+			debug "starting handshake..."

+			self:_lock( false, true, true )  -- unlock read/write events, but keep interface locked 

+			self.eventhandshake = addevent( base, self.conn, EV_READWRITE, handshakecallback, cfg.HANDSHAKE_TIMEOUT )

+			return true

+	end

+	function interface_mt:_destroy()  -- close this interface + events and call last listener

+			debug( "closing client with id:", self )

+			self:_lock( true, true, true )  -- first of all, lock the interface to avoid further actions

+			local _

+			_ = self.eventread and self.eventread:close( )  -- close events; this must be called outside of the event callbacks!

+			if self.type == "client" then

+				_ = self.eventwrite and self.eventwrite:close( )

+				_ = self.eventhandshake and self.eventhandshake:close( )

+				_ = self.eventstarthandshake and self.eventstarthandshake:close( )

+				_ = self.eventconnect and self.eventconnect:close( )

+				_ = self.eventsession and self.eventsession:close( )

+				_ = self.eventwritetimeout and self.eventwritetimeout:close( )

+				_ = self.eventreadtimeout and self.eventreadtimeout:close( )

+				_ = self.ondisconnect and self:ondisconnect( self.fatalerror )  -- call ondisconnect listener (wont be the case if handshake failed on connect)

+				_ = self.conn and self.conn:close( ) -- close connection, must also be called outside of any socket registered events!

+				self._server:counter(-1);

+				self.eventread, self.eventwrite = nil, nil

+				self.eventstarthandshake, self.eventhandshake, self.eventclose = nil, nil, nil

+				self.readcallback, self.writecallback = nil, nil

+			else

+				self.conn:close( )

+				self.eventread, self.eventclose = nil, nil

+				self.interface, self.readcallback = nil, nil

+			end

+			interfacelist( "delete", self )

+			return true

+	end

+	function interface_mt:_lock(nointerface, noreading, nowriting)  -- lock or unlock this interface or events

+			self.nointerface, self.noreading, self.nowriting = nointerface, noreading, nowriting

+			return nointerface, noreading, nowriting

+	end

+

+	function interface_mt:counter(c)

+		if c then

+			self._connections = self._connections - c

+		end

+		return self._connections

+	end

+	

+	-- Public methods

+	function interface_mt:write(data)

+		--vdebug( "try to send data to client, id/data:", self, data )

+		data = tostring( data )

+		local len = string_len( data )

+		local total = len + self.writebufferlen

+		if total > cfg.MAX_SEND_LENGTH then  -- check buffer length

+			local err = "send buffer exceeded"

+			debug( "error:", err )  -- to much, check your app

+			return nil, err

+		end 

+		self.writebuffer = self.writebuffer .. data -- new buffer

+		self.writebufferlen = total

+		if not self.eventwrite then  -- register new write event

+			--vdebug( "register new write event" )

+			self.eventwrite = addevent( base, self.conn, EV_WRITE, self.writecallback, cfg.WRITE_TIMEOUT )

+		end

+		return true

+	end

+	function interface_mt:close(now)

+		debug( "try to close client connection with id:", self )

+		if self.type == "client" then

+			self.fatalerror = "client to close"

+			if ( not self.eventwrite ) or now then  -- try to close immediately

+				self:_lock( true, true, true )

+				self:_close()

+				return true

+			else  -- wait for incomplete write request

+				self:_lock( true, true, false )

+				debug "closing delayed until writebuffer is empty"

+				return nil, "writebuffer not empty, waiting"

+			end

+		else

+			debug( "try to close server with id:", self, "args:", now )

+			self.fatalerror = "server to close"

+			self:_lock( true )

+			local count = 0

+			for _, item in ipairs( interfacelist( ) ) do

+				if ( item.type ~= "server" ) and ( item._server == self ) then  -- client/server match

+					if item:close( now ) then  -- writebuffer was empty

+						count = count + 1

+					end

+				end

+			end

+			local timeout = 0  -- dont wait for unfinished writebuffers of clients...

+			if not now then

+				timeout = cfg.WRITE_TIMEOUT  -- ...or wait for it

+			end

+			self:_close( timeout )  -- add new event to remove the server interface

+			debug( "seconds remained until server is closed:", timeout )

+			return count  -- returns finished clients with empty writebuffer

+		end

+	end

+	

+	function interface_mt:server()

+		return self._server or self;

+	end

+	

+	function interface_mt:port()

+		return self._port

+	end

+	

+	function interface_mt:ip()

+		return self._ip

+	end

+	

+	function interface_mt:ssl()

+		return self.usingssl

+	end

+

+	function interface_mt:type()

+		return self._type or "client"

+	end

+	

+	function interface_mt:connections()

+		return self._connections

+	end

+	

+	function interface_mt:address()

+		return self.addr

+	end

+	

+			

+	

+	function interface_mt:starttls()

+		debug( "try to start ssl at client id:", self )

+		local err

+		if not self.sslctx then  -- no ssl available

+			err = "no ssl context available"

+		elseif self.usingssl then  -- startssl was already called

+			err = "ssl already active"

+		end

+		if err then

+			debug( "error:", err )

+			return nil, err      

+		end

+		self.usingssl = true

+		self.startsslcallback = function( )  -- we have to start the handshake outside of a read/write event

+			self:_start_ssl();

+			self.eventstarthandshake = nil

+			return -1

+		end

+		if not self.eventwrite then

+			self:_lock( true, true, true )  -- lock the interface, to not disturb the handshake

+			self.eventstarthandshake = addevent( base, nil, EV_TIMEOUT, self.startsslcallback, 0 )  -- add event to start handshake

+		else  -- wait until writebuffer is empty

+			self:_lock( true, true, false )

+			debug "ssl session delayed until writebuffer is empty..."

+		end

+		return true

+	end

+	

+	function interface_mt.onconnect()

+	end

+end			

+

+-- End of client interface methods

+

+local handleclient;

+do

+	local string_sub = string.sub  -- caching table lookups

+	local string_len = string.len

+	local addevent = base.addevent

+	local coroutine_wrap = coroutine.wrap

+	local socket_gettime = socket.gettime

+	local coroutine_yield = coroutine.yield

+	function handleclient( client, ip, port, server, pattern, listener, _, sslctx )  -- creates an client interface

+		--vdebug("creating client interfacce...")

+		local interface = {

+			type = "client";

+			conn = client;

+			currenttime = socket_gettime( );  -- safe the origin

+			writebuffer = "";  -- writebuffer

+			writebufferlen = 0;  -- length of writebuffer

+			send = client.send;  -- caching table lookups

+			receive = client.receive;

+			onconnect = listener.onconnect;  -- will be called when client disconnects

+			ondisconnect = listener.ondisconnect;  -- will be called when client disconnects

+			onincoming = listener.onincoming;  -- will be called when client sends data

+			eventread = false, eventwrite = false, eventclose = false,

+			eventhandshake = false, eventstarthandshake = false;  -- event handler

+			eventconnect = false, eventsession = false;  -- more event handler...

+			eventwritetimeout = false;  -- even more event handler...

+			eventreadtimeout = false;

+			fatalerror = false;  -- error message

+			writecallback = false;  -- will be called on write events

+			readcallback = false;  -- will be called on read events

+			nointerface = true;  -- lock/unlock parameter of this interface

+			noreading = false, nowriting = false;  -- locks of the read/writecallback

+			startsslcallback = false;  -- starting handshake callback

+			position = false;  -- position of client in interfacelist

+			

+			-- Properties

+			_ip = ip, _port = port, _server = server, _pattern = pattern,

+			_sslctx = sslctx; -- parameters

+			_usingssl = false;  -- client is using ssl;

+		}

+		interface.writecallback = function( event )  -- called on write events

+			--vdebug( "new client write event, id/ip/port:", interface, ip, port )

+			if interface.nowriting or ( interface.fatalerror and ( "client to close" ~= interface.fatalerror ) ) then  -- leave this event

+				--vdebug( "leaving this event because:", interface.nowriting or interface.fatalerror )

+				interface.eventwrite = false

+				return -1

+			end

+			if EV_TIMEOUT == event then  -- took too long to write some data to socket -> disconnect

+				interface.fatalerror = "timeout during writing"

+				debug( "writing failed:", interface.fatalerror ) 

+				interface:_close()

+				interface.eventwrite = false

+				return -1

+			else  -- can write :)

+				if interface.usingssl then  -- handle luasec

+					if interface.eventreadtimeout then  -- we have to read first

+						local ret = interface.readcallback( )  -- call readcallback

+						--vdebug( "tried to read in writecallback, result:", ret )

+					end

+					if interface.eventwritetimeout then  -- luasec only

+						interface.eventwritetimeout:close( )  -- first we have to close timeout event which where regged after a wantread error

+						interface.eventwritetimeout = false

+					end

+				end

+				local succ, err, byte = interface.send( interface.conn, interface.writebuffer, 1, interface.writebufferlen )

+				--vdebug( "write data:", interface.writebuffer, "error:", err, "part:", byte )

+				if succ then  -- writing succesful

+					interface.writebuffer = ""

+					interface.writebufferlen = 0

+					if interface.fatalerror then

+						debug "closing client after writing"

+						interface:_close()  -- close interface if needed

+					elseif interface.startsslcallback then  -- start ssl connection if needed

+						debug "starting ssl handshake after writing"

+						interface.eventstarthandshake = addevent( base, nil, EV_TIMEOUT, interface.startsslcallback, 0 )

+					elseif interface.eventreadtimeout then

+						return EV_WRITE, EV_TIMEOUT

+					end

+					interface.eventwrite = nil

+					return -1

+				elseif byte then  -- want write again

+					--vdebug( "writebuffer is not empty:", err )

+					interface.writebuffer = string_sub( interface.writebuffer, byte + 1, interface.writebufferlen )  -- new buffer

+					interface.writebufferlen = interface.writebufferlen - byte            

+					if "wantread" == err then  -- happens only with luasec

+						local callback = function( )

+							interface:_close()

+							interface.eventwritetimeout = nil

+							return evreturn, evtimeout

+						end

+						interface.eventwritetimeout = addevent( base, nil, EV_TIMEOUT, callback, cfg.WRITE_TIMEOUT )  -- reg a new timeout event

+						debug( "wantread during write attemp, reg it in readcallback but dont know what really happens next..." )

+						-- hopefully this works with luasec; its simply not possible to use 2 different write events on a socket in luaevent

+						return -1

+					end

+					return EV_WRITE, cfg.WRITE_TIMEOUT 

+				else  -- connection was closed during writing or fatal error

+					interface.fatalerror = err or "fatal error"

+					debug( "connection failed in write event:", interface.fatalerror ) 

+					interface:_close()

+					interface.eventwrite = nil

+					return -1

+				end

+			end

+		end

+		local usingssl, receive = interface._usingssl, interface.receive;

+		interface.readcallback = function( event )  -- called on read events

+			--vdebug( "new client read event, id/ip/port:", interface, ip, port )

+			if interface.noreading or interface.fatalerror then  -- leave this event

+				--vdebug( "leaving this event because:", interface.noreading or interface.fatalerror )

+				interface.eventread = nil

+				return -1

+			end

+			if EV_TIMEOUT == event then  -- took too long to get some data from client -> disconnect

+				interface.fatalerror = "timeout during receiving"

+				debug( "connection failed:", interface.fatalerror ) 

+				interface:_close()

+				interface.eventread = nil

+				return -1

+			else -- can read

+				if usingssl then  -- handle luasec

+					if interface.eventwritetimeout then  -- ok, in the past writecallback was regged

+						local ret = interface.writecallback( )  -- call it

+						--vdebug( "tried to write in readcallback, result:", ret )

+					end

+					if interface.eventreadtimeout then

+						interface.eventreadtimeout:close( )

+						interface.eventreadtimeout = nil

+					end

+				end

+				local buffer, err, part = receive( client, pattern )  -- receive buffer with "pattern"

+				--vdebug( "read data:", buffer, "error:", err, "part:", part )        

+				buffer = buffer or part or ""

+				local len = string_len( buffer )

+				if len > cfg.MAX_READ_LENGTH then  -- check buffer length

+					interface.fatalerror = "receive buffer exceeded"

+					debug( "fatal error:", interface.fatalerror )

+					interface:_close()

+					interface.eventread = nil

+					return -1

+				end

+				if err and ( "timeout" ~= err ) then

+					if "wantwrite" == err then -- need to read on write event

+						if not interface.eventwrite then  -- register new write event if needed

+							interface.eventwrite = addevent( base, interface.conn, EV_WRITE, interface.writecallback, cfg.WRITE_TIMEOUT )

+						end

+						interface.eventreadtimeout = addevent( base, nil, EV_TIMEOUT,

+							function( )

+								interface:_close()

+							end, cfg.READ_TIMEOUT

+						)             

+						debug( "wantwrite during read attemp, reg it in writecallback but dont know what really happens next..." )

+						-- to be honest i dont know what happens next, if it is allowed to first read, the write etc...

+					else  -- connection was closed or fatal error            

+						interface.fatalerror = err

+						debug( "connection failed in read event:", interface.fatalerror ) 

+						interface:_close()

+						interface.eventread = nil

+						return -1

+					end

+				end

+				interface.onincoming( interface, buffer, err )  -- send new data to listener

+				return EV_READ, cfg.READ_TIMEOUT

+			end

+		end

+

+		client:settimeout( 0 )  -- set non blocking

+		setmetatable(interface, interface_mt)

+		interfacelist( "add", interface )  -- add to interfacelist

+		return interface

+	end

+end

+

+local handleserver

+do

+	function handleserver( server, addr, port, pattern, listener, sslctx, startssl )  -- creates an server interface

+		debug "creating server interface..."

+		local interface = {

+			_connections = 0;

+			

+			conn = server;

+			onconnect = listener.onconnect;  -- will be called when new client connected

+			eventread = false;  -- read event handler

+			eventclose = false; -- close event handler

+			readcallback = false; -- read event callback

+			fatalerror = false; -- error message

+			nointerface = true;  -- lock/unlock parameter

+		}

+		interface.readcallback = function( event )  -- server handler, called on incoming connections

+			--vdebug( "server can accept, id/addr/port:", interface, addr, port )

+			if interface.fatalerror then

+				--vdebug( "leaving this event because:", self.fatalerror )

+				interface.eventread = nil

+				return -1

+			end

+			local delay = cfg.ACCEPT_DELAY

+			if EV_TIMEOUT == event then

+				if interface._connections >= cfg.MAX_CONNECTIONS then  -- check connection count

+					debug( "to many connections, seconds to wait for next accept:", delay )

+					return EV_TIMEOUT, delay  -- timeout...

+				else

+					return EV_READ  -- accept again

+				end

+			end

+			--vdebug("max connection check ok, accepting...")

+			local client, err = server:accept()    -- try to accept; TODO: check err

+			while client do

+				if interface._connections >= cfg.MAX_CONNECTIONS then

+					client:close( )  -- refuse connection

+					debug( "maximal connections reached, refuse client connection; accept delay:", delay )

+					return EV_TIMEOUT, delay  -- delay for next accept attemp

+				end

+				local ip, port = client:getpeername( )

+				interface._connections = interface._connections + 1  -- increase connection count

+				local clientinterface = handleclient( client, ip, port, interface, pattern, listener, nil, sslctx )

+				--vdebug( "client id:", clientinterface, "startssl:", startssl )

+				if startssl then

+					clientinterface:_start_ssl( clientinterface.onconnect )

+				else

+					clientinterface:_start_session( clientinterface.onconnect )

+				end

+				debug( "accepted incoming client connection from:", ip, port )

+				client, err = server:accept()    -- try to accept again

+			end

+			return EV_READ

+		end

+		

+		server:settimeout( 0 )

+		setmetatable(interface, interface_mt)

+		interfacelist( "add", interface )

+		interface:_start_session()

+		return interface

+	end

+end

+

+local addserver = ( function( )

+	return function( addr, port, listener, pattern, backlog, sslcfg, startssl )  -- TODO: check arguments

+		debug( "creating new tcp server with following parameters:", addr or "nil", port or "nil", sslcfg or "nil", startssl or "nil")

+		local server, err = socket.bind( addr, port, backlog )  -- create server socket

+		if not server then

+			debug( "creating server socket failed because:", err )

+			return nil, err

+		end

+		local sslctx

+		if sslcfg then

+			if not ssl then

+				debug "fatal error: luasec not found"

+				return nil, "luasec not found"

+			end

+			sslctx, err = ssl.newcontext( sslcfg )

+			if err then

+				debug( "error while creating new ssl context for server socket:", err )

+				return nil, err

+			end

+		end      

+		local interface = handleserver( server, addr, port, pattern, listener, sslctx, startssl )  -- new server handler

+		debug( "new server created with id:", tostring(interface))

+		return interface

+	end

+end )( )

+

+local wrapclient = ( function( )

+	return function( client, addr, serverport, listener, pattern, localaddr, localport, sslcfg, startssl )

+		debug( "try to connect to:", addr, serverport, "with parameters:", pattern, localaddr, localport, sslcfg, startssl )

+		local sslctx

+		if sslcfg then  -- handle ssl/new context

+			if not ssl then

+				debug "need luasec, but not available" 

+				return nil, "luasec not found"

+			end

+			sslctx, err = ssl.newcontext( sslcfg )

+			if err then

+				debug( "cannot create new ssl context:", err )

+				return nil, err

+			end

+		end

+	end

+end )( )

+

+local addclient = ( function( )

+	return function( addr, serverport, listener, pattern, localaddr, localport, sslcfg, startssl )

+		local client, err = socket.tcp()  -- creating new socket

+		if not client then

+			debug( "cannot create socket:", err ) 

+			return nil, err

+		end

+		client:settimeout( 0 )  -- set nonblocking

+		if localaddr then

+			local res, err = client:bind( localaddr, localport, -1 )

+			if not res then

+				debug( "cannot bind client:", err )

+				return nil, err

+			end

+		end

+		local res, err = client:connect( addr, serverport )  -- connect

+		if res or ( err == "timeout" ) then

+			local ip, port = client:getsockname( )

+			local server = function( )

+				return nil, "this is a dummy server interface"

+			end

+			local interface = handleclient( client, ip, port, server, pattern, listener, sslctx )

+			interface:_start_connection( startssl )

+			debug( "new connection id:", interface )

+			return interface, err

+		else

+			debug( "new connection failed:", err )

+			return nil, err

+		end

+		return wrapclient( client, addr, serverport, listener, pattern, localaddr, localport, sslcfg, startssl )    

+	end

+end )( )

+

+local loop = function( )  -- starts the event loop

+	return base:loop( )

+end

+

+local newevent = ( function( )

+	local add = base.addevent

+	return function( ... )

+		return add( base, ... )

+	end

+end )( )

+

+local closeallservers = function( arg )

+	for _, item in ipairs( interfacelist( ) ) do

+		if item "type" == "server" then

+			item( "close", arg )

+		end

+	end

+end

+

+return {

+

+	cfg = cfg,

+	base = base,

+	loop = loop,

+	event = event,

+	addevent = newevent,

+	addserver = addserver,

+	addclient = addclient,

+	wrapclient = wrapclient,

+	closeallservers = closeallservers,

+

+	__NAME = SCRIPT_NAME,

+	__DATE = LAST_MODIFIED,

+	__AUTHOR = SCRIPT_AUTHOR,

+	__VERSION = SCRIPT_VERSION,

+

+}