It's a multi-client TCP server "base" that has all the boilerplate code done, the only thing that one needs to do is just whip their protocol code in to it and it's ready to go. I've included a little few-line example bit in it (in the #region stuff) for a simple echo server. A quick way to see the example work is to just start this up and use a telnet client to connect to it on the port that you chose to have it bind (default in the one I'm posting is port 8080), typing a sentence, and pressing enter. This server makes use of setting the TCPTimeout option to 0, making it quite efficient when a high number of clients are connected and making it faster at accepting new connections. It does not use a fixed-size array for storing client connections, but instead dynamically re-sizes the client array when clients disconnect or connect (Setting $MaxClients to 0 makes the number of simultaneous clients only limited by RAM or AutoIt internal limits, whatever is reached first. I've tested this at 10,000 concurrent connections successfully, albeit with some slightly elevated CPU usage ). The server also implements a simple per-client packet buffer (as shown in the little echo example) which can come in handy for things such as large packets from file transferring and such. Instead of only relying on checking @error after a TCPRecv call to determine if a client disconnected (which can lie in certain cases), this uses a checking function which implements both that @error check and an idle timeout check that disconnects the client if they have not sent anything in a certain period of time.
This is not really aimed at people who are unfamiliar with sockets work in AutoIt, as this provides no real application layer protocol, you must make that yourself. The only thing this does is do all the hard and/or tedious work of managing what happens when clients try connecting, how packet data should be buffered, and when a connection should be considered "dead".
If you use this in a project, a simple little comment saying you used it would be nice
#cs ---------------------------------------------------------------------------- AutoIt Version: 184.108.40.206 Author: Ken Piper Script Function: Template multi-client server base code. Use as a base for making an efficient server program. This base will just accept connections and echo back what it receives, and kill the connection if it is dead or inactive for x seconds. It will not do any other work, that must be added seperately! #ce ---------------------------------------------------------------------------- TCPStartup() Opt("TCPTimeout", 0) #region ;Safe-to-edit things are below Global $BindIP = "0.0.0.0" ;Listen on all addresses Global $BindPort = 8080 ;Listen on port 8080 Global $Timeout = 15000 ;Max idle time is 15 seconds before calling a connection "dead" Global $PacketSize = 2048 ;Max packet size per-check is 2KB Global $MaxClients = 50 ;Max simultaneous clients is 50 #endregion ;Stuff you shouldn't touch is below Global $Listen Global $Clients ;[Index][Socket, IP, Timestamp, Buffer] Global $Ws2_32 = DllOpen("Ws2_32.dll") ;Open Ws2_32.dll, it might get used a lot Global $NTDLL = DllOpen("ntdll.dll") ;Open ntdll.dll, it WILL get used a lot Global $CleanupTimer = TimerInit() ;This is used to time when things should be cleaned up OnAutoItExitRegister("Close") ;Register this function to be called if the server needs to exit $Clients = 0 $Listen = TCPListen($BindIP, $BindPort, $MaxClients) ;Start listening on the given IP/port If @error Then Exit 1 ;Exit with return code 1 if something was already bound to that IP and port While 1 USleep(5000, $NTDLL) ;This is needed because TCPTimeout is disabled. Without this it will run one core at ~100%. ;The USleep function takes MICROseconds, not milliseconds, so 1000 = 1ms delay. ;When working with this granularity, you have to take in to account the time it takes to complete USleep(). ;1000us (1ms) is about as fast as this should be set. If you need more performance, set this from 5000 to 1000, ;but doing so will make it consume a bit more CPU time to get that extra bit of performance. Check() ;Check recv buffers and do things If TimerDiff($CleanupTimer) > 1000 Then ;If it has been more than 1000ms since Cleanup() was last called, call it now $CleanupTimer = TimerInit() ;Reset $CleanupTimer, so it is ready to be called again Cleanup() ;Clean up the dead connections EndIf Local $iSock = TCPAccept($Listen) ;See if anything wants to connect If $iSock = -1 Then ContinueLoop ;If nothing wants to connect, restart at the top of the loop Local $iSize = UBound($Clients, 1) ;Something wants to connect, so get the number of people currently connected here If $iSize - 1 > $MaxClients And $MaxClients > 0 Then ;If $MaxClients is greater than 0 (meaning if there is a max connection limit) then check if that has been reached TCPCloseSocket($iSock) ;It has been reached, close the new connection and continue back at the top of the loop ContinueLoop EndIf ReDim $Clients[$iSize + 1] ;There is room for a new connection, allocate space for it here $Clients = $iSize ;Update the number of connected clients $Clients[$iSize] = $iSock ;Set the socket ID of the connection $Clients[$iSize] = SocketToIP($iSock, $Ws2_32) ;Set the IP Address the connection is from $Clients[$iSize] = TimerInit() ;Set the timestamp for the last known activity timer $Clients[$iSize] = "" ;Blank the recv buffer WEnd Func Check() ;Function for processing If $Clients < 1 Then Return ;If there are no clients connected, stop the function right now For $i = 1 To $Clients ;Loop through all connected clients $sRecv = TCPRecv($Clients[$i], $PacketSize) ;Read $PacketSize bytes from the current client's buffer If $sRecv <> "" Then $Clients[$i] &= $sRecv ;If there was more data sent from the client, add it to the buffer If $Clients[$i] = "" Then ContinueLoop ;If the buffer is empty, stop right here and check more clients $Clients[$i] = TimerInit() ;If it got this far, there is data to be parsed, so update the activity timer #region ;Example packet processing stuff here. This is handling for a simple "echo" server with per-packet handling $sRecv = StringLeft($Clients[$i], StringInStr($Clients[$i], @CRLF, 0, -1)) ;Pull all data to the left of the last @CRLF in the buffer ;This does NOT pull the first complete packet, this pulls ALL complete packets, leaving only potentially incomplete packets in the buffer If $sRecv = "" Then ContinueLoop ;Check if there were any complete "packets" $Clients[$i] = StringTrimLeft($Clients[$i], StringLen($sRecv) + 1) ;remove what was just read from the client's buffer $sPacket = StringSplit($sRecv, @CRLF, 1) ;Split all complete packets up in to an array, so it is easy to work with them For $j = 1 To $sPacket ;Loop through each complete packet; This is where any packet processing should be done TCPSend($Clients[$i], "Echoing line: " & $sPacket[$j] & @CRLF) ;Echo back the packet the client sent Next #endregion ;Example Next EndFunc Func Cleanup() ;Clean up any disconnected clients to regain resources If $Clients < 1 Then Return ;If no clients are connected then return Local $iNewSize = 0 For $i = 1 To $Clients ;Loop through all connected clients $Clients[$i] &= TCPRecv($Clients[$i], $PacketSize) ;Dump any data not-yet-seen in to their recv buffer If @error Or TimerDiff($Clients[$i]) > $Timeout Then ;Check to see if the connection has been inactive for a while or if there was an error TCPCloseSocket($Clients[$i]) ;If yes, close the connection $Clients[$i] = -1 ;Set the socket ID to an invalid socket Else $iNewSize += 1 EndIf Next If $iNewSize < $Clients Then ;If any dead connections were found, drop them from the client array and resize the array Local $iSize = UBound($Clients, 2) - 1 Local $aTemp[$iNewSize + 1][$iSize + 1] Local $iCount = 1 For $i = 1 To $Clients If $Clients[$i] = -1 Then ContinueLoop For $j = 0 To $iSize $aTemp[$iCount][$j] = $Clients[$i][$j] Next $iCount += 1 Next $aTemp = $iNewSize $Clients = $aTemp EndIf EndFunc Func Close() DllClose($Ws2_32) ;Close the open handle to Ws2_32.dll DllClose($NTDLL) ;Close the open handle to ntdll.dll For $i = 1 To $Clients ;Loop through the connected clients TCPCloseSocket($Clients[$i]) ;Force the client's connection closed Next TCPShutdown() ;Shut down networking stuff EndFunc Func SocketToIP($iSock, $hDLL = "Ws2_32.dll") ;A rewrite of that _SocketToIP function that has been floating around for ages Local $structName = DllStructCreate("short;ushort;uint;char") Local $sRet = DllCall($hDLL, "int", "getpeername", "int", $iSock, "ptr", DllStructGetPtr($structName), "int*", DllStructGetSize($structName)) If Not @error Then $sRet = DllCall($hDLL, "str", "inet_ntoa", "int", DllStructGetData($structName, 3)) If Not @error Then Return $sRet EndIf Return "0.0.0.0" ;Something went wrong, return an invalid IP EndFunc Func USleep($iUsec, $hDLL = "ntdll.dll") ;A rewrite of the _HighPrecisionSleep function made by monoceres (Thanks!) Local $hStruct = DllStructCreate("int64") DllStructSetData($hStruct, 1, -1 * ($iUsec * 10)) DllCall($hDLL, "dword", "ZwDelayExecution", "int", 0, "ptr", DllStructGetPtr($hStruct)) EndFunc
Comments, questions, and criticisms are appreciated!
(Edited to clear up formatting a bit in the [autoit] tags)
(Edited again to fix a bug in how it cleaned up the connection, and fixed a spelling error in the post)
(Edited once more to fix a very rare corner-case that could happen when getting many connections and disconnections in a short amount of time)
(Edited a bit of code to fix issues with reading multiple buffered packets)
(Edited yet again to fix some spelling in the post and clean the code a bit; I try to keep this code up-to-date with the source file on my computer )
(Edited to add a massive performance increase when handling large numbers of connected clients and the client array needs to be trimmed. I've seen up to a 500x speed increase on my computer!)
(Edited again, apparently I forgot to set the max pending connections in TCPListen, leading for some pretty slow connection-accepting! Sorry about that.)
Edited by Kealper, 15 December 2012 - 10:44 AM.