net/server_event.lua

   1 --[[
   2
   3
   4                         server.lua based on lua/libevent by blastbeat
   5
   6                         notes:
   7                         -- when using luaevent, never register 2 or more EV_READ at one socket, same for EV_WRITE
   8                         -- you cant even register a new EV_READ/EV_WRITE callback inside another one
   9                         -- to do some of the above, use timeout events or something what will called from outside
  10                         -- dont let garbagecollect eventcallbacks, as long they are running
  11                         -- when using luasec, there are 4 cases of timeout errors: wantread or wantwrite during reading or writing
  12
  13 --]]
  14
  15 local SCRIPT_NAME           = "server_event.lua"
  16 local SCRIPT_VERSION        = "0.05"
  17 local SCRIPT_AUTHOR         = "blastbeat"
  18 local LAST_MODIFIED         = "2009/11/20"
  19
  20 local cfg = {
  21         MAX_CONNECTIONS       = 100000,  -- max per server connections (use "ulimit -n" on *nix)
  22         MAX_HANDSHAKE_ATTEMPTS= 1000,  -- attempts to finish ssl handshake
  23         HANDSHAKE_TIMEOUT     = 60,  -- timeout in seconds per handshake attempt
  24         MAX_READ_LENGTH       = 1024 * 1024 * 1024 * 1024,  -- max bytes allowed to read from sockets
  25         MAX_SEND_LENGTH       = 1024 * 1024 * 1024 * 1024,  -- max bytes size of write buffer (for writing on sockets)
  26         ACCEPT_QUEUE          = 128,  -- might influence the length of the pending sockets queue
  27         ACCEPT_DELAY          = 10,  -- seconds to wait until the next attempt of a full server to accept
  28         READ_TIMEOUT          = 60 * 60 * 6,  -- timeout in seconds for read data from socket
  29         WRITE_TIMEOUT         = 180,  -- timeout in seconds for write data on socket
  30         CONNECT_TIMEOUT       = 20,  -- timeout in seconds for connection attempts
  31         CLEAR_DELAY           = 5,  -- seconds to wait for clearing interface list (and calling ondisconnect listeners)
  32         DEBUG                 = true,  -- show debug messages
  33 }
  34
  35 local function use(x) return rawget(_G, x); end
  36 local ipairs = use "ipairs"
  37 local string = use "string"
  38 local select = use "select"
  39 local require = use "require"
  40 local tostring = use "tostring"
  41 local coroutine = use "coroutine"
  42 local setmetatable = use "setmetatable"
  43
  44 local t_insert = table.insert
  45 local t_concat = table.concat
  46
  47 local ssl = use "ssl"
  48 local socket = use "socket" or require "socket"
  49
  50 local log = require ("util.logger").init("socket")
  51
  52 local function debug(...)
  53         return log("debug", ("%s "):rep(select('#', ...)), ...)
  54 end
  55 local vdebug = debug;
  56
  57 local bitor = ( function( ) -- thx Rici Lake
  58         local hasbit = function( x, p )
  59                 return x % ( p + p ) >= p
  60         end
  61         return function( x, y )
  62                 local p = 1
  63                 local z = 0
  64                 local limit = x > y and x or y
  65                 while p <= limit do
  66                         if hasbit( x, p ) or hasbit( y, p ) then
  67                                 z = z + p
  68                         end
  69                         p = p + p
  70                 end
  71                 return z
  72         end
  73 end )( )
  74
  75 local event = require "luaevent.core"
  76 local base = event.new( )
  77 local EV_READ = event.EV_READ
  78 local EV_WRITE = event.EV_WRITE
  79 local EV_TIMEOUT = event.EV_TIMEOUT
  80 local EV_SIGNAL = event.EV_SIGNAL
  81
  82 local EV_READWRITE = bitor( EV_READ, EV_WRITE )
  83
  84 local interfacelist = ( function( )  -- holds the interfaces for sockets
  85         local array = { }
  86         local len = 0
  87         return function( method, arg )
  88                 if "add" == method then
  89                         len = len + 1
  90                         array[ len ] = arg
  91                         arg:_position( len )
  92                         return len
  93                 elseif "delete" == method then
  94                         if len <= 0 then
  95                                 return nil, "array is already empty"
  96                         end
  97                         local position = arg:_position()  -- get position in array
  98                         if position ~= len then
  99                                 local interface = array[ len ]  -- get last interface
 100                                 array[ position ] = interface  -- copy it into free position
 101                                 array[ len ] = nil  -- free last position
 102                                 interface:_position( position )  -- set new position in array
 103                         else  -- free last position
 104                                 array[ len ] = nil
 105                         end
 106                         len = len - 1
 107                         return len
 108                 else
 109                         return array
 110                 end
 111         end
 112 end )( )
 113
 114 -- Client interface methods
 115 local interface_mt
 116 do
 117         interface_mt = {}; interface_mt.__index = interface_mt;
 118
 119         local addevent = base.addevent
 120         local coroutine_wrap, coroutine_yield = coroutine.wrap,coroutine.yield
 121
 122         -- Private methods
 123         function interface_mt:_position(new_position)
 124                         self.position = new_position or self.position
 125                         return self.position;
 126         end
 127         function interface_mt:_close()
 128                 return self:_destroy();
 129         end
 130
 131         function interface_mt:_start_connection(plainssl) -- should be called from addclient
 132                         local callback = function( event )
 133                                 if EV_TIMEOUT == event then  -- timeout during connection
 134                                         self.fatalerror = "connection timeout"
 135                                         self:ontimeout()  -- call timeout listener
 136                                         self:_close()
 137                                         debug( "new connection failed. id:", self.id, "error:", self.fatalerror )
 138                                 else
 139                                         if plainssl and ssl then  -- start ssl session
 140                                                 self:starttls(self._sslctx, true)
 141                                         else  -- normal connection
 142                                                 self:_start_session(true)
 143                                         end
 144                                         debug( "new connection established. id:", self.id )
 145                                 end
 146                                 self.eventconnect = nil
 147                                 return -1
 148                         end
 149                         self.eventconnect = addevent( base, self.conn, EV_WRITE, callback, cfg.CONNECT_TIMEOUT )
 150                         return true
 151         end
 152         function interface_mt:_start_session(call_onconnect) -- new session, for example after startssl
 153                 if self.type == "client" then
 154                         local callback = function( )
 155                                 self:_lock( false,  false, false )
 156                                 --vdebug( "start listening on client socket with id:", self.id )
 157                                 self.eventread = addevent( base, self.conn, EV_READ, self.readcallback, cfg.READ_TIMEOUT );  -- register callback
 158                                 if call_onconnect then
 159                                         self:onconnect()
 160                                 end
 161                                 self.eventsession = nil
 162                                 return -1
 163                         end
 164                         self.eventsession = addevent( base, nil, EV_TIMEOUT, callback, 0 )
 165                 else
 166                         self:_lock( false )
 167                         --vdebug( "start listening on server socket with id:", self.id )
 168                         self.eventread = addevent( base, self.conn, EV_READ, self.readcallback )  -- register callback
 169                 end
 170                 return true
 171         end
 172         function interface_mt:_start_ssl(call_onconnect) -- old socket will be destroyed, therefore we have to close read/write events first
 173                         --vdebug( "starting ssl session with client id:", self.id )
 174                         local _
 175                         _ = self.eventread and self.eventread:close( )  -- close events; this must be called outside of the event callbacks!
 176                         _ = self.eventwrite and self.eventwrite:close( )
 177                         self.eventread, self.eventwrite = nil, nil
 178                         local err
 179                         self.conn, err = ssl.wrap( self.conn, self._sslctx )
 180                         if err then
 181                                 self.fatalerror = err
 182                                 self.conn = nil  -- cannot be used anymore
 183                                 if call_onconnect then
 184                                         self.ondisconnect = nil  -- dont call this when client isnt really connected
 185                                 end
 186                                 self:_close()
 187                                 debug( "fatal error while ssl wrapping:", err )
 188                                 return false
 189                         end
 190                         self.conn:settimeout( 0 )  -- set non blocking
 191                         local handshakecallback = coroutine_wrap(
 192                                 function( event )
 193                                         local _, err
 194                                         local attempt = 0
 195                                         local maxattempt = cfg.MAX_HANDSHAKE_ATTEMPTS
 196                                         while attempt < maxattempt do  -- no endless loop
 197                                                 attempt = attempt + 1
 198                                                 debug( "ssl handshake of client with id:"..tostring(self)..", attempt:"..attempt )
 199                                                 if attempt > maxattempt then
 200                                                         self.fatalerror = "max handshake attempts exceeded"
 201                                                 elseif EV_TIMEOUT == event then
 202                                                         self.fatalerror = "timeout during handshake"
 203                                                 else
 204                                                         _, err = self.conn:dohandshake( )
 205                                                         if not err then
 206                                                                 self:_lock( false, false, false )  -- unlock the interface; sending, closing etc allowed
 207                                                                 self.send = self.conn.send  -- caching table lookups with new client object
 208                                                                 self.receive = self.conn.receive
 209                                                                 if not call_onconnect then  -- trigger listener
 210                                                                         self:onstatus("ssl-handshake-complete");
 211                                                                 end
 212                                                                 self:_start_session( call_onconnect )
 213                                                                 debug( "ssl handshake done" )
 214                                                                 self.eventhandshake = nil
 215                                                                 return -1
 216                                                         end
 217                                                         if err == "wantwrite" then
 218                                                                 event = EV_WRITE
 219                                                         elseif err == "wantread" then
 220                                                                 event = EV_READ
 221                                                         else
 222                                                                 debug( "ssl handshake error:", err )
 223                                                                 self.fatalerror = err
 224                                                         end
 225                                                 end
 226                                                 if self.fatalerror then
 227                                                         if call_onconnect then
 228                                                                 self.ondisconnect = nil  -- dont call this when client isnt really connected
 229                                                         end
 230                                                         self:_close()
 231                                                         debug( "handshake failed because:", self.fatalerror )
 232                                                         self.eventhandshake = nil
 233                                                         return -1
 234                                                 end
 235                                                 event = coroutine_yield( event, cfg.HANDSHAKE_TIMEOUT )  -- yield this monster...
 236                                         end
 237                                 end
 238                         )
 239                         debug "starting handshake..."
 240                         self:_lock( false, true, true )  -- unlock read/write events, but keep interface locked
 241                         self.eventhandshake = addevent( base, self.conn, EV_READWRITE, handshakecallback, cfg.HANDSHAKE_TIMEOUT )
 242                         return true
 243         end
 244         function interface_mt:_destroy()  -- close this interface + events and call last listener
 245                         debug( "closing client with id:", self.id, self.fatalerror )
 246                         self:_lock( true, true, true )  -- first of all, lock the interface to avoid further actions
 247                         local _
 248                         _ = self.eventread and self.eventread:close( )
 249                         if self.type == "client" then
 250                                 _ = self.eventwrite and self.eventwrite:close( )
 251                                 _ = self.eventhandshake and self.eventhandshake:close( )
 252                                 _ = self.eventstarthandshake and self.eventstarthandshake:close( )
 253                                 _ = self.eventconnect and self.eventconnect:close( )
 254                                 _ = self.eventsession and self.eventsession:close( )
 255                                 _ = self.eventwritetimeout and self.eventwritetimeout:close( )
 256                                 _ = self.eventreadtimeout and self.eventreadtimeout:close( )
 257                                 _ = self.ondisconnect and self:ondisconnect( self.fatalerror ~= "client to close" and self.fatalerror)  -- call ondisconnect listener (wont be the case if handshake failed on connect)
 258                                 _ = self.conn and self.conn:close( ) -- close connection
 259                                 _ = self._server and self._server:counter(-1);
 260                                 self.eventread, self.eventwrite = nil, nil
 261                                 self.eventstarthandshake, self.eventhandshake, self.eventclose = nil, nil, nil
 262                                 self.readcallback, self.writecallback = nil, nil
 263                         else
 264                                 self.conn:close( )
 265                                 self.eventread, self.eventclose = nil, nil
 266                                 self.interface, self.readcallback = nil, nil
 267                         end
 268                         interfacelist( "delete", self )
 269                         return true
 270         end
 271
 272         function interface_mt:_lock(nointerface, noreading, nowriting)  -- lock or unlock this interface or events
 273                         self.nointerface, self.noreading, self.nowriting = nointerface, noreading, nowriting
 274                         return nointerface, noreading, nowriting
 275         end
 276
 277         --TODO: Deprecate
 278         function interface_mt:lock_read(switch)
 279                 if switch then
 280                         return self:pause();
 281                 else
 282                         return self:resume();
 283                 end
 284         end
 285
 286         function interface_mt:pause()
 287                 return self:_lock(self.nointerface, true, self.nowriting);
 288         end
 289
 290         function interface_mt:resume()
 291                 self:_lock(self.nointerface, false, self.nowriting);
 292                 if self.readcallback and not self.eventread then
 293                         self.eventread = addevent( base, self.conn, EV_READ, self.readcallback, cfg.READ_TIMEOUT );  -- register callback
 294                         return true;
 295                 end
 296         end
 297
 298         function interface_mt:counter(c)
 299                 if c then
 300                         self._connections = self._connections + c
 301                 end
 302                 return self._connections
 303         end
 304
 305         -- Public methods
 306         function interface_mt:write(data)
 307                 if self.nowriting then return nil, "locked" end
 308                 --vdebug( "try to send data to client, id/data:", self.id, data )
 309                 data = tostring( data )
 310                 local len = #data
 311                 local total = len + self.writebufferlen
 312                 if total > cfg.MAX_SEND_LENGTH then  -- check buffer length
 313                         local err = "send buffer exceeded"
 314                         debug( "error:", err )  -- to much, check your app
 315                         return nil, err
 316                 end
 317                 t_insert(self.writebuffer, data) -- new buffer
 318                 self.writebufferlen = total
 319                 if not self.eventwrite then  -- register new write event
 320                         --vdebug( "register new write event" )
 321                         self.eventwrite = addevent( base, self.conn, EV_WRITE, self.writecallback, cfg.WRITE_TIMEOUT )
 322                 end
 323                 return true
 324         end
 325         function interface_mt:close()
 326                 if self.nointerface then return nil, "locked"; end
 327                 debug( "try to close client connection with id:", self.id )
 328                 if self.type == "client" then
 329                         self.fatalerror = "client to close"
 330                         if self.eventwrite then -- wait for incomplete write request
 331                                 self:_lock( true, true, false )
 332                                 debug "closing delayed until writebuffer is empty"
 333                                 return nil, "writebuffer not empty, waiting"
 334                         else -- close now
 335                                 self:_lock( true, true, true )
 336                                 self:_close()
 337                                 return true
 338                         end
 339                 else
 340                         debug( "try to close server with id:", tostring(self.id))
 341                         self.fatalerror = "server to close"
 342                         self:_lock( true )
 343                         self:_close( 0 )
 344                         return true
 345                 end
 346         end
 347
 348         function interface_mt:socket()
 349                 return self.conn
 350         end
 351
 352         function interface_mt:server()
 353                 return self._server or self;
 354         end
 355
 356         function interface_mt:port()
 357                 return self._port
 358         end
 359
 360         function interface_mt:serverport()
 361                 return self._serverport
 362         end
 363
 364         function interface_mt:ip()
 365                 return self._ip
 366         end
 367
 368         function interface_mt:ssl()
 369                 return self._usingssl
 370         end
 371         interface_mt.clientport = interface_mt.port -- COMPAT server_select
 372
 373         function interface_mt:type()
 374                 return self._type or "client"
 375         end
 376
 377         function interface_mt:connections()
 378                 return self._connections
 379         end
 380
 381         function interface_mt:address()
 382                 return self.addr
 383         end
 384
 385         function interface_mt:set_sslctx(sslctx)
 386                 self._sslctx = sslctx;
 387                 if sslctx then
 388                         self.starttls = nil; -- use starttls() of interface_mt
 389                 else
 390                         self.starttls = false; -- prevent starttls()
 391                 end
 392         end
 393
 394         function interface_mt:set_mode(pattern)
 395                 if pattern then
 396                         self._pattern = pattern;
 397                 end
 398                 return self._pattern;
 399         end
 400
 401         function interface_mt:set_send(new_send)
 402                 -- No-op, we always use the underlying connection's send
 403         end
 404
 405         function interface_mt:starttls(sslctx, call_onconnect)
 406                 debug( "try to start ssl at client id:", self.id )
 407                 local err
 408                 self._sslctx = sslctx;
 409                 if self._usingssl then  -- startssl was already called
 410                         err = "ssl already active"
 411                 end
 412                 if err then
 413                         debug( "error:", err )
 414                         return nil, err
 415                 end
 416                 self._usingssl = true
 417                 self.startsslcallback = function( )  -- we have to start the handshake outside of a read/write event
 418                         self.startsslcallback = nil
 419                         self:_start_ssl(call_onconnect);
 420                         self.eventstarthandshake = nil
 421                         return -1
 422                 end
 423                 if not self.eventwrite then
 424                         self:_lock( true, true, true )  -- lock the interface, to not disturb the handshake
 425                         self.eventstarthandshake = addevent( base, nil, EV_TIMEOUT, self.startsslcallback, 0 )  -- add event to start handshake
 426                 else  -- wait until writebuffer is empty
 427                         self:_lock( true, true, false )
 428                         debug "ssl session delayed until writebuffer is empty..."
 429                 end
 430                 self.starttls = false;
 431                 return true
 432         end
 433
 434         function interface_mt:setoption(option, value)
 435                 if self.conn.setoption then
 436                         return self.conn:setoption(option, value);
 437                 end
 438                 return false, "setoption not implemented";
 439         end
 440
 441         function interface_mt:setlistener(listener)
 442                 self:ondetach(); -- Notify listener that it is no longer responsible for this connection
 443                 self.onconnect, self.ondisconnect, self.onincoming,
 444                 self.ontimeout, self.onstatus, self.ondetach
 445                         = listener.onconnect, listener.ondisconnect, listener.onincoming,
 446                         listener.ontimeout, listener.onstatus, listener.ondetach;
 447         end
 448
 449         -- Stub handlers
 450         function interface_mt:onconnect()
 451         end
 452         function interface_mt:onincoming()
 453         end
 454         function interface_mt:ondisconnect()
 455         end
 456         function interface_mt:ontimeout()
 457         end
 458         function interface_mt:ondrain()
 459         end
 460         function interface_mt:ondetach()
 461         end
 462         function interface_mt:onstatus()
 463         end
 464 end
 465
 466 -- End of client interface methods
 467
 468 local handleclient;
 469 do
 470         local string_sub = string.sub  -- caching table lookups
 471         local addevent = base.addevent
 472         local socket_gettime = socket.gettime
 473         function handleclient( client, ip, port, server, pattern, listener, sslctx )  -- creates an client interface
 474                 --vdebug("creating client interfacce...")
 475                 local interface = {
 476                         type = "client";
 477                         conn = client;
 478                         currenttime = socket_gettime( );  -- safe the origin
 479                         writebuffer = {};  -- writebuffer
 480                         writebufferlen = 0;  -- length of writebuffer
 481                         send = client.send;  -- caching table lookups
 482                         receive = client.receive;
 483                         onconnect = listener.onconnect;  -- will be called when client disconnects
 484                         ondisconnect = listener.ondisconnect;  -- will be called when client disconnects
 485                         onincoming = listener.onincoming;  -- will be called when client sends data
 486                         ontimeout = listener.ontimeout; -- called when fatal socket timeout occurs
 487                         ondrain = listener.ondrain; -- called when writebuffer is empty
 488                         ondetach = listener.ondetach; -- called when disassociating this listener from this connection
 489                         onstatus = listener.onstatus; -- called for status changes (e.g. of SSL/TLS)
 490                         eventread = false, eventwrite = false, eventclose = false,
 491                         eventhandshake = false, eventstarthandshake = false;  -- event handler
 492                         eventconnect = false, eventsession = false;  -- more event handler...
 493                         eventwritetimeout = false;  -- even more event handler...
 494                         eventreadtimeout = false;
 495                         fatalerror = false;  -- error message
 496                         writecallback = false;  -- will be called on write events
 497                         readcallback = false;  -- will be called on read events
 498                         nointerface = true;  -- lock/unlock parameter of this interface
 499                         noreading = false, nowriting = false;  -- locks of the read/writecallback
 500                         startsslcallback = false;  -- starting handshake callback
 501                         position = false;  -- position of client in interfacelist
 502
 503                         -- Properties
 504                         _ip = ip, _port = port, _server = server, _pattern = pattern,
 505                         _serverport = (server and server:port() or nil),
 506                         _sslctx = sslctx; -- parameters
 507                         _usingssl = false;  -- client is using ssl;
 508                 }
 509                 if not ssl then interface.starttls = false; end
 510                 interface.id = tostring(interface):match("%x+$");
 511                 interface.writecallback = function( event )  -- called on write events
 512                         --vdebug( "new client write event, id/ip/port:", interface, ip, port )
 513                         if interface.nowriting or ( interface.fatalerror and ( "client to close" ~= interface.fatalerror ) ) then  -- leave this event
 514                                 --vdebug( "leaving this event because:", interface.nowriting or interface.fatalerror )
 515                                 interface.eventwrite = false
 516                                 return -1
 517                         end
 518                         if EV_TIMEOUT == event then  -- took too long to write some data to socket -> disconnect
 519                                 interface.fatalerror = "timeout during writing"
 520                                 debug( "writing failed:", interface.fatalerror )
 521                                 interface:_close()
 522                                 interface.eventwrite = false
 523                                 return -1
 524                         else  -- can write :)
 525                                 if interface._usingssl then  -- handle luasec
 526                                         if interface.eventreadtimeout then  -- we have to read first
 527                                                 local ret = interface.readcallback( )  -- call readcallback
 528                                                 --vdebug( "tried to read in writecallback, result:", ret )
 529                                         end
 530                                         if interface.eventwritetimeout then  -- luasec only
 531                                                 interface.eventwritetimeout:close( )  -- first we have to close timeout event which where regged after a wantread error
 532                                                 interface.eventwritetimeout = false
 533                                         end
 534                                 end
 535                                 interface.writebuffer = { t_concat(interface.writebuffer) }
 536                                 local succ, err, byte = interface.conn:send( interface.writebuffer[1], 1, interface.writebufferlen )
 537                                 --vdebug( "write data:", interface.writebuffer, "error:", err, "part:", byte )
 538                                 if succ then  -- writing succesful
 539                                         interface.writebuffer[1] = nil
 540                                         interface.writebufferlen = 0
 541                                         interface:ondrain();
 542                                         if interface.fatalerror then
 543                                                 debug "closing client after writing"
 544                                                 interface:_close()  -- close interface if needed
 545                                         elseif interface.startsslcallback then  -- start ssl connection if needed
 546                                                 debug "starting ssl handshake after writing"
 547                                                 interface.eventstarthandshake = addevent( base, nil, EV_TIMEOUT, interface.startsslcallback, 0 )
 548                                         elseif interface.writebufferlen ~= 0 then
 549                                                 -- data possibly written from ondrain
 550                                                 return EV_WRITE, cfg.WRITE_TIMEOUT
 551                                         elseif interface.eventreadtimeout then
 552                                                 return EV_WRITE, cfg.WRITE_TIMEOUT
 553                                         end
 554                                         interface.eventwrite = nil
 555                                         return -1
 556                                 elseif byte and (err == "timeout" or err == "wantwrite") then  -- want write again
 557                                         --vdebug( "writebuffer is not empty:", err )
 558                                         interface.writebuffer[1] = string_sub( interface.writebuffer[1], byte + 1, interface.writebufferlen )  -- new buffer
 559                                         interface.writebufferlen = interface.writebufferlen - byte
 560                                         if "wantread" == err then  -- happens only with luasec
 561                                                 local callback = function( )
 562                                                         interface:_close()
 563                                                         interface.eventwritetimeout = nil
 564                                                         return -1;
 565                                                 end
 566                                                 interface.eventwritetimeout = addevent( base, nil, EV_TIMEOUT, callback, cfg.WRITE_TIMEOUT )  -- reg a new timeout event
 567                                                 debug( "wantread during write attempt, reg it in readcallback but dont know what really happens next..." )
 568                                                 -- hopefully this works with luasec; its simply not possible to use 2 different write events on a socket in luaevent
 569                                                 return -1
 570                                         end
 571                                         return EV_WRITE, cfg.WRITE_TIMEOUT
 572                                 else  -- connection was closed during writing or fatal error
 573                                         interface.fatalerror = err or "fatal error"
 574                                         debug( "connection failed in write event:", interface.fatalerror )
 575                                         interface:_close()
 576                                         interface.eventwrite = nil
 577                                         return -1
 578                                 end
 579                         end
 580                 end
 581
 582                 interface.readcallback = function( event )  -- called on read events
 583                         --vdebug( "new client read event, id/ip/port:", tostring(interface.id), tostring(ip), tostring(port) )
 584                         if interface.noreading or interface.fatalerror then  -- leave this event
 585                                 --vdebug( "leaving this event because:", tostring(interface.noreading or interface.fatalerror) )
 586                                 interface.eventread = nil
 587                                 return -1
 588                         end
 589                         if EV_TIMEOUT == event then  -- took too long to get some data from client -> disconnect
 590                                 interface.fatalerror = "timeout during receiving"
 591                                 debug( "connection failed:", interface.fatalerror )
 592                                 interface:_close()
 593                                 interface.eventread = nil
 594                                 return -1
 595                         else -- can read
 596                                 if interface._usingssl then  -- handle luasec
 597                                         if interface.eventwritetimeout then  -- ok, in the past writecallback was regged
 598                                                 local ret = interface.writecallback( )  -- call it
 599                                                 --vdebug( "tried to write in readcallback, result:", tostring(ret) )
 600                                         end
 601                                         if interface.eventreadtimeout then
 602                                                 interface.eventreadtimeout:close( )
 603                                                 interface.eventreadtimeout = nil
 604                                         end
 605                                 end
 606                                 local buffer, err, part = interface.conn:receive( interface._pattern )  -- receive buffer with "pattern"
 607                                 --vdebug( "read data:", tostring(buffer), "error:", tostring(err), "part:", tostring(part) )
 608                                 buffer = buffer or part
 609                                 if buffer and #buffer > cfg.MAX_READ_LENGTH then  -- check buffer length
 610                                         interface.fatalerror = "receive buffer exceeded"
 611                                         debug( "fatal error:", interface.fatalerror )
 612                                         interface:_close()
 613                                         interface.eventread = nil
 614                                         return -1
 615                                 end
 616                                 if err and ( err ~= "timeout" and err ~= "wantread" ) then
 617                                         if "wantwrite" == err then -- need to read on write event
 618                                                 if not interface.eventwrite then  -- register new write event if needed
 619                                                         interface.eventwrite = addevent( base, interface.conn, EV_WRITE, interface.writecallback, cfg.WRITE_TIMEOUT )
 620                                                 end
 621                                                 interface.eventreadtimeout = addevent( base, nil, EV_TIMEOUT,
 622                                                         function( )
 623                                                                 interface:_close()
 624                                                         end, cfg.READ_TIMEOUT
 625                                                 )
 626                                                 debug( "wantwrite during read attempt, reg it in writecallback but dont know what really happens next..." )
 627                                                 -- to be honest i dont know what happens next, if it is allowed to first read, the write etc...
 628                                         else  -- connection was closed or fatal error
 629                                                 interface.fatalerror = err
 630                                                 debug( "connection failed in read event:", interface.fatalerror )
 631                                                 interface:_close()
 632                                                 interface.eventread = nil
 633                                                 return -1
 634                                         end
 635                                 else
 636                                         interface.onincoming( interface, buffer, err )  -- send new data to listener
 637                                 end
 638                                 if interface.noreading then
 639                                         interface.eventread = nil;
 640                                         return -1;
 641                                 end
 642                                 return EV_READ, cfg.READ_TIMEOUT
 643                         end
 644                 end
 645
 646                 client:settimeout( 0 )  -- set non blocking
 647                 setmetatable(interface, interface_mt)
 648                 interfacelist( "add", interface )  -- add to interfacelist
 649                 return interface
 650         end
 651 end
 652
 653 local handleserver
 654 do
 655         function handleserver( server, addr, port, pattern, listener, sslctx )  -- creates an server interface
 656                 debug "creating server interface..."
 657                 local interface = {
 658                         _connections = 0;
 659
 660                         conn = server;
 661                         onconnect = listener.onconnect;  -- will be called when new client connected
 662                         eventread = false;  -- read event handler
 663                         eventclose = false; -- close event handler
 664                         readcallback = false; -- read event callback
 665                         fatalerror = false; -- error message
 666                         nointerface = true;  -- lock/unlock parameter
 667
 668                         _ip = addr, _port = port, _pattern = pattern,
 669                         _sslctx = sslctx;
 670                 }
 671                 interface.id = tostring(interface):match("%x+$");
 672                 interface.readcallback = function( event )  -- server handler, called on incoming connections
 673                         --vdebug( "server can accept, id/addr/port:", interface, addr, port )
 674                         if interface.fatalerror then
 675                                 --vdebug( "leaving this event because:", self.fatalerror )
 676                                 interface.eventread = nil
 677                                 return -1
 678                         end
 679                         local delay = cfg.ACCEPT_DELAY
 680                         if EV_TIMEOUT == event then
 681                                 if interface._connections >= cfg.MAX_CONNECTIONS then  -- check connection count
 682                                         debug( "to many connections, seconds to wait for next accept:", delay )
 683                                         return EV_TIMEOUT, delay  -- timeout...
 684                                 else
 685                                         return EV_READ  -- accept again
 686                                 end
 687                         end
 688                         --vdebug("max connection check ok, accepting...")
 689                         local client, err = server:accept()    -- try to accept; TODO: check err
 690                         while client do
 691                                 if interface._connections >= cfg.MAX_CONNECTIONS then
 692                                         client:close( )  -- refuse connection
 693                                         debug( "maximal connections reached, refuse client connection; accept delay:", delay )
 694                                         return EV_TIMEOUT, delay  -- delay for next accept attempt
 695                                 end
 696                                 local client_ip, client_port = client:getpeername( )
 697                                 interface._connections = interface._connections + 1  -- increase connection count
 698                                 local clientinterface = handleclient( client, client_ip, client_port, interface, pattern, listener, sslctx )
 699                                 --vdebug( "client id:", clientinterface, "startssl:", startssl )
 700                                 if ssl and sslctx then
 701                                         clientinterface:starttls(sslctx, true)
 702                                 else
 703                                         clientinterface:_start_session( true )
 704                                 end
 705                                 debug( "accepted incoming client connection from:", client_ip or "<unknown IP>", client_port or "<unknown port>", "to", port or "<unknown port>");
 706
 707                                 client, err = server:accept()    -- try to accept again
 708                         end
 709                         return EV_READ
 710                 end
 711
 712                 server:settimeout( 0 )
 713                 setmetatable(interface, interface_mt)
 714                 interfacelist( "add", interface )
 715                 interface:_start_session()
 716                 return interface
 717         end
 718 end
 719
 720 local addserver = ( function( )
 721         return function( addr, port, listener, pattern, sslcfg, startssl )  -- TODO: check arguments
 722                 --vdebug( "creating new tcp server with following parameters:", addr or "nil", port or "nil", sslcfg or "nil", startssl or "nil")
 723                 local server, err = socket.bind( addr, port, cfg.ACCEPT_QUEUE )  -- create server socket
 724                 if not server then
 725                         debug( "creating server socket on "..addr.." port "..port.." failed:", err )
 726                         return nil, err
 727                 end
 728                 local sslctx
 729                 if sslcfg then
 730                         if not ssl then
 731                                 debug "fatal error: luasec not found"
 732                                 return nil, "luasec not found"
 733                         end
 734                         sslctx, err = sslcfg
 735                         if err then
 736                                 debug( "error while creating new ssl context for server socket:", err )
 737                                 return nil, err
 738                         end
 739                 end
 740                 local interface = handleserver( server, addr, port, pattern, listener, sslctx, startssl )  -- new server handler
 741                 debug( "new server created with id:", tostring(interface))
 742                 return interface
 743         end
 744 end )( )
 745
 746 local addclient, wrapclient
 747 do
 748         function wrapclient( client, ip, port, listeners, pattern, sslctx )
 749                 local interface = handleclient( client, ip, port, nil, pattern, listeners, sslctx )
 750                 interface:_start_connection(sslctx)
 751                 return interface, client
 752                 --function handleclient( client, ip, port, server, pattern, listener, _, sslctx )  -- creates an client interface
 753         end
 754
 755         function addclient( addr, serverport, listener, pattern, localaddr, localport, sslcfg, startssl )
 756                 local client, err = socket.tcp()  -- creating new socket
 757                 if not client then
 758                         debug( "cannot create socket:", err )
 759                         return nil, err
 760                 end
 761                 client:settimeout( 0 )  -- set nonblocking
 762                 if localaddr then
 763                         local res, err = client:bind( localaddr, localport, -1 )
 764                         if not res then
 765                                 debug( "cannot bind client:", err )
 766                                 return nil, err
 767                         end
 768                 end
 769                 local sslctx
 770                 if sslcfg then  -- handle ssl/new context
 771                         if not ssl then
 772                                 debug "need luasec, but not available"
 773                                 return nil, "luasec not found"
 774                         end
 775                         sslctx, err = sslcfg
 776                         if err then
 777                                 debug( "cannot create new ssl context:", err )
 778                                 return nil, err
 779                         end
 780                 end
 781                 local res, err = client:connect( addr, serverport )  -- connect
 782                 if res or ( err == "timeout" ) then
 783                         local ip, port = client:getsockname( )
 784                         local interface = wrapclient( client, ip, serverport, listener, pattern, sslctx, startssl )
 785                         interface:_start_connection( startssl )
 786                         debug( "new connection id:", interface.id )
 787                         return interface, err
 788                 else
 789                         debug( "new connection failed:", err )
 790                         return nil, err
 791                 end
 792         end
 793 end
 794
 795
 796 local loop = function( )  -- starts the event loop
 797         base:loop( )
 798         return "quitting";
 799 end
 800
 801 local newevent = ( function( )
 802         local add = base.addevent
 803         return function( ... )
 804                 return add( base, ... )
 805         end
 806 end )( )
 807
 808 local closeallservers = function( arg )
 809         for _, item in ipairs( interfacelist( ) ) do
 810                 if item.type == "server" then
 811                         item:close( arg )
 812                 end
 813         end
 814 end
 815
 816 local function setquitting(yes)
 817         if yes then
 818                  -- Quit now
 819                  closeallservers();
 820                  base:loopexit();
 821         end
 822 end
 823
 824 local function get_backend()
 825         return base:method();
 826 end
 827
 828 -- We need to hold onto the events to stop them
 829 -- being garbage-collected
 830 local signal_events = {}; -- [signal_num] -> event object
 831 local function hook_signal(signal_num, handler)
 832         local function _handler(event)
 833                 local ret = handler();
 834                 if ret ~= false then -- Continue handling this signal?
 835                         return EV_SIGNAL; -- Yes
 836                 end
 837                 return -1; -- Close this event
 838         end
 839         signal_events[signal_num] = base:addevent(signal_num, EV_SIGNAL, _handler);
 840         return signal_events[signal_num];
 841 end
 842
 843 local function link(sender, receiver, buffersize)
 844         local sender_locked;
 845
 846         function receiver:ondrain()
 847                 if sender_locked then
 848                         sender:resume();
 849                         sender_locked = nil;
 850                 end
 851         end
 852
 853         function sender:onincoming(data)
 854                 receiver:write(data);
 855                 if receiver.writebufferlen >= buffersize then
 856                         sender_locked = true;
 857                         sender:pause();
 858                 end
 859         end
 860         sender:set_mode("*a");
 861 end
 862
 863 return {
 864
 865         cfg = cfg,
 866         base = base,
 867         loop = loop,
 868         link = link,
 869         event = event,
 870         event_base = base,
 871         addevent = newevent,
 872         addserver = addserver,
 873         addclient = addclient,
 874         wrapclient = wrapclient,
 875         setquitting = setquitting,
 876         closeall = closeallservers,
 877         get_backend = get_backend,
 878         hook_signal = hook_signal,
 879
 880         __NAME = SCRIPT_NAME,
 881         __DATE = LAST_MODIFIED,
 882         __AUTHOR = SCRIPT_AUTHOR,
 883         __VERSION = SCRIPT_VERSION,
 884
 885 }