Server.c

// This article and all its includes are licenced under LGPL // GPL: http://www.gnu.org/copyleft/lesser.html // SRC: http://www.organicdesign.co.nz/server.c

1. define svrDELAY 1 // normal operation is 0 for no delay
2. define svrPAKSIZE 128 // keep packet-size small for non-multithreaded design
3. define svrBUFSIZE 10000 // dictates max message size
4. define svrMAXCLIENTS 1000 // used by listen()

void server(); void client(); int nonblocking(int socket);

void server_init() {

#if __WIN32__ WSADATA wsaData; if (WSAStartup(MAKEWORD(2,0),&wsaData)!=0) logErr("WSAStartup() failed!"); #else int WSAGetLastError() { return errno; } #endif

// Set up structures for socket & select struct sockaddr_in addr; struct timeval to; fd_set *fdset; unsigned long int sockopt_on = 1; int sock, szAddr = sizeof(struct sockaddr_in); memset((char*)&addr, 0, szAddr); // zero the struct addr.sin_family = AF_INET; addr.sin_port = htons(port); addr.sin_addr.s_addr = htonl(INADDR_ANY);

// struct for a stream-node's state to point to typedef struct siStruct { int fd, inptr, outptr; char *inbuf, *outbuf; } streamInfo;

// Do the usual socket polava: create,options,bind,listen if ((sock = socket(PF_INET,SOCK_STREAM,IPPROTO_TCP))<0) logErrNum("socket() failed returning %d",WSAGetLastError()); if (setsockopt(sock,SOL_SOCKET,SO_REUSEADDR,(char*)&sockopt_on,sizeof(int))<0) logErr("setsockopt() failed!"); if (bind(nonblocking(sock),(struct sockaddr*)&addr,szAddr)<0) logErr("bind() failed!"); if (listen(sock,svrMAXCLIENTS)<0) logErr("listen() failed!"); if (errno) logAdd("Server failed to start!");

// make the passed socket non-blocking so accept() returns straight away for multiplexed model // - if no incoming requests, returns EAGAIN or EWOULDBLOCK state int nonblocking(int socket) { #if __WIN32__ ioctlsocket(socket,FIONBIO,&sockopt_on); #else fcntl(socket,F_SETFL,fcntl(socket,F_GETFL)|O_NONBLOCK); #endif return socket; }

}

// Parses a message content and responds to client void processMessage(char* msg) {

// Create a new context node

// validate and extract event, params and mime-type // /GET\s+\/+(.*?)(\/(.+))?\s+(HTTP\/[0-9.]+)/

// add appropriate response to nodal context // - restart, click?x&y, else content/mime/type

}

// Function called by each stream-node in network's reduction loop // - there is also a streams-container node containing zero or more stream nodes void server() { FD_ZERO(fdset); FD_SET(sock,fdset); to.tv_sec = to.tv_usec = svrDELAY; if (select(sock+1,fdset,NULL,NULL,&to)>0) { // New connection request, accpet and create new stream-node int fd = nonblocking(accept(sock,NULL,NULL)); if (fd>0) { streamInfo *newsi = malloc(sizeof(streamInfo)); newsi->fd = fd; newsi->inbuf = malloc(svrBUFSIZE); newsi->outbuf = malloc(svrBUFSIZE); newsi->inptr = 0; newsi->outptr = 0; //nodeSetState(newNode = add-me-to-stream-loop, nodeSTREAMINFO, newsi); nodeSetValue(nodeROOT,nodeCURRENT,nodeROOT); // nodally exit on request test } else logErr("accept(): failed!"); } }

// Each of the stream nodes points to this function in its State void client() {

// Get the info for this stream ready for reading/writing a packet if necessary streamInfo *info = nodeGetState(this, nodeSTREAMINFO); int i,fd = info->fd, inptr = info->inptr, outptr = info->outptr; char *inbuf = info->inbuf, *outbuf = info->outbuf;

// Data to receive? FD_ZERO(fdset); FD_SET(fd,fdset); to.tv_sec = to.tv_usec = svrDELAY; if (select(fd+1,fdset,NULL,NULL,&to)>0) { // read a packet into inbuf if (i = recv(fd,inbuf+inptr,svrPAKSIZE,0)>0) {

// test if complete message in buffer char *message = NULL; while (i--) { // /\r?\n\r?\n\x00?/ }

if (message) { //inptr = info->inptr -= msg_size; // hook a process into the loop } } else if (i == 0) { // zero bytes to read, do orderly termination // todo: remove this stream node from loop free(inbuf); free(outbuf); free(info); } else logErr("recv(): failed!"); }

// Data to send? FD_ZERO(fdset); FD_SET(fd,fdset); to.tv_sec = to.tv_usec = svrDELAY; if (select(fd+1,NULL,fdset,NULL,&to)>0) { // write a packet from outbuf int len = svrPAKSIZE; // or less if (send(fd,outbuf+outptr,len,0)<0) logErr("send() failed!"); }

}