net/server_event.lua

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