added new networking subsystem (early stage - files are not compiled yet during normal build!)

Note
	The files i added / modifications i did, are not affecting a normal build
	nothing gets changed yet!

	Linux 2.5+ only yet.

	


git-svn-id: https://rathena.svn.sourceforge.net/svnroot/rathena/trunk@16271 54d463be-8e91-2dee-dedb-b68131a5f0ec

1 files changed, 1062 insertions, 0 deletions

diff --git a/src/common/network.c b/src/common/network.c
new file mode 100644
index 000000000..2574f3cc1
--- /dev/null
+++ b/src/common/network.c
@@ -0,0 +1,1062 @@
+ //
+// Network Subsystem (previously known as socket system)
+//
+// Author: Florian Wilkemeyer <fw@f-ws.de>
+//
+// Copyright (c) rAthena Project (www.rathena.org) - Licensed under GNU GPL
+// For more information, see LICENCE in the main folder
+//
+//
+//#ifdef HAVE_ACCETP4
+#define _GNU_SOURCE
+//#endif
+
+#include <stdio.h>
+#include <string.h>
+#include <unistd.h>
+#include <errno.h>
+
+#include <sys/types.h>
+#include <sys/fcntl.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <netinet/tcp.h>
+#include <arpa/inet.h>
+
+
+#include "../common/cbasetypes.h"
+#include "../common/showmsg.h"
+#include "../common/timer.h"
+#include "../common/evdp.h"
+#include "../common/netbuffer.h"
+
+#include "../common/network.h"
+
+#define ENABLE_IPV6
+#define HAVE_ACCEPT4
+#define EVENTS_PER_CYCLE 10
+#define PARANOID_CHECKS
+
+// Local Vars (settings..)
+static int l_ListenBacklog = 64;
+
+//
+// Global Session Array (previously exported as session[]
+//
+SESSION g_Session[MAXCONN];
+
+
+//
+static bool onSend(int32 fd);
+
+
+#define _network_free_netbuf_async( buf ) add_timer( 0, _network_async_free_netbuf_proc, 0,  (intptr_t) buf)
+static int _network_async_free_netbuf_proc(int tid, unsigned int tick, int id, intptr_t data){
+	// netbuf is in data
+	netbuffer_put( (netbuf)data );
+
+	return 0;
+}//end: _network_async_free_netbuf_proc()
+
+
+
+void network_init(){
+	SESSION *s;
+	int32 i;
+	
+	memset(g_Session, 0x00, (sizeof(SESSION) * MAXCONN) );
+	
+	for(i = 0; i < MAXCONN; i++){
+		s = &g_Session[i];
+		
+		s->type = NST_FREE;
+		s->disconnect_in_progress = false;
+				
+	}
+	
+	// Initialize the correspondig event dispatcher
+	evdp_init();
+
+	//
+	add_timer_func_list(_network_async_free_netbuf_proc, "_network_async_free_netbuf_proc");
+		
+}//end: network_init()
+
+
+void network_final(){
+
+	// @TODO:
+	// .. disconnect and cleanup everything!
+	
+	evdp_final();
+
+}//end: network_final()
+
+
+void network_do(){
+	struct EVDP_EVENT l_events[EVENTS_PER_CYCLE];
+	register struct EVDP_EVENT *ev;
+	register int n, nfds;
+	register SESSION *s;
+	
+	nfds = evdp_wait( l_events,	EVENTS_PER_CYCLE, 1000); // @TODO: timer_getnext()
+	
+	for(n = 0; n < nfds; n++){
+		ev = &l_events[n];
+		s = &g_Session[ ev->fd ];
+		
+		if(ev->events & EVDP_EVENT_HUP){
+			network_disconnect( ev->fd );	
+			continue; // no further event processing.
+		}// endif vent is HUP (disconnect)
+		
+		
+		if(ev->events & EVDP_EVENT_IN){
+			
+			if(s->onRecv != NULL){
+				if( false == s->onRecv(ev->fd) ){
+					network_disconnect(ev->fd);
+					continue; // ..
+				}
+			}else{
+				ShowError("network_do: fd #%u has no onRecv proc set. - disconnecting\n", ev->fd);
+				network_disconnect(ev->fd);
+				continue;
+			}	
+						
+		}// endif event is IN (recv)
+		
+		
+		if(ev->events & EVDP_EVENT_OUT){
+			if(s->onSend != NULL){
+				if( false == s->onSend(ev->fd) ){
+					network_disconnect(ev->fd);
+					continue;
+				}
+			}else{
+				ShowError("network_do: fd #%u has no onSend proc set. - disconnecting\n", ev->fd);
+				network_disconnect(ev->fd);
+				continue;
+			}
+		}// endif event is OUT (send)
+		
+	}//endfor
+			
+}//end: network_do()
+
+
+static bool _setnonblock(int32 fd){
+	int flags = fcntl(fd, F_GETFL, 0);
+	if(fcntl(fd, F_SETFL, flags | O_NONBLOCK) != 0)
+		return false;
+
+	return true;
+}//end: _setnonblock()
+
+
+static bool _network_accept(int32 fd){
+	SESSION *listener = &g_Session[fd];
+	SESSION *s; 
+	union{
+		struct sockaddr_in v4;
+#ifdef ENABLE_IPV6
+		struct sockaddr_in6 v6;
+#endif
+	} _addr;
+	int newfd;
+	socklen_t addrlen;
+	struct sockaddr *addr;
+
+	// Accept until OS returns - nothing to accept anymore
+	// - this is required due to our EVDP abstraction. (which handles on listening sockets similar to epoll's EPOLLET flag.)
+	while(1){
+#ifdef ENABLE_IPV6
+		if(listener->v6 == true){
+			addrlen = sizeof(_addr.v6);
+			addr = (struct sockaddr*)&_addr.v6;
+		}else{
+#endif
+			addrlen = sizeof(_addr.v4);
+			addr = (struct sockaddr*)&_addr.v4;		
+#ifdef ENABLE_IPV6
+		}
+#endif
+
+#ifdef HAVE_ACCEPT4
+		newfd = accept4(fd, addr, &addrlen, SOCK_NONBLOCK);
+#else
+		newfd = accept(fd, addr, &addrlen);
+#endif
+
+		if(newfd == -1){
+			if(errno == EAGAIN || errno == EWOULDBLOCK)
+				break; // this is fully valid & whished., se explaination on top of while(1)
+			
+			// Otherwis .. we have serious problems :( seems tahat our listner has gone away..
+			// @TODO handle this .. 
+			ShowError("_network_accept: accept() returned error. closing listener. (errno: %u / %s)\n", errno, strerror(errno));
+
+			return false; // will call disconnect after return.
+			//break;
+		}
+
+#ifndef HAVE_ACCEPT4 // no accept4 means, we have to set nonblock by ourself. ..
+		if(_setnonblock(newfd) == false){
+			ShowError("_network_accept: failed to set newly accepted connection nonblocking (errno: %u / %s). - disconnecting.\n", errno, strerror(errno));
+			close(newfd);
+			continue; 
+		}
+#endif
+
+		// Check connection limits.
+		if(newfd >= MAXCONN){
+			ShowError("_network_accept: failed to accept connection - MAXCONN (%u) exceeded.\n", MAXCONN);
+			close(newfd);
+			continue; // we have to loop over the events (and disconnect them too ..) but otherwise we would leak event notifications.
+		}
+
+
+		// Create new Session.
+		s = &g_Session[newfd];
+		s->type = NST_CLIENT;
+		
+		// The new connection inherits listenr's handlers.
+		s->onDisconnect = listener->onDisconnect;
+		s->onConnect = listener->onConnect; // maybe useless but .. fear the future .. :~ 
+	
+		// Register the new connection @ EVDP
+		if( evdp_addclient(newfd, &s->evdp_data) == false){
+			ShowError("_network_accept: failed to accept connection - event subsystem returned an error.\n");
+			close(newfd);
+			s->type = NST_FREE;
+		}
+		
+		// Call the onConnect handler on the listener.
+		if( listener->onConnect(newfd) == false ){
+			// Resfused by onConnect handler..
+			evdp_remove(newfd, &s->evdp_data);
+			
+			close(newfd);
+			s->type = NST_FREE;
+			
+			s->data = NULL; // be on the safe side ~ !
+			continue;
+		}
+		
+		
+	}
+
+	return true;
+}//end: _network_accept()
+
+
+void network_disconnect(int32 fd){
+	SESSION *s = &g_Session[fd];
+	netbuf b, bn;
+	
+	// Prevent recursive calls 
+	// by wrong implemented on disconnect handlers.. and such..
+	if(s->disconnect_in_progress == true)
+		return; 	
+		
+	s->disconnect_in_progress = true;
+	
+	
+	// Disconnect Todo:
+	//	- Call onDisconnect Handler
+	//	- Release all Assigned buffers.
+	//	- remove from event system (notifications)
+	//	- cleanup session structure
+	//	- close connection. 
+	//
+	
+	if(s->onDisconnect != NULL && 
+		s->type != NST_LISTENER){
+		
+		s->onDisconnect( fd );
+	}
+
+	// Read Buffer 
+	if(s->read.buf != NULL){
+		netbuffer_put(s->read.buf);
+		s->read.buf = NULL;
+	}
+
+	// Write Buffer(s)
+	b = s->write.buf;
+	while(1){
+		if(b == NULL) break;
+
+		bn = b->next;
+		
+		netbuffer_put(b);
+		
+		b = bn;
+	}
+	s->write.buf = NULL;
+	s->write.buf_last = NULL;
+	
+	s->write.n_outstanding = 0;
+	s->write.max_outstanding = 0;
+	
+		
+	// Remove from event system.
+	evdp_remove(fd, &s->evdp_data);
+	
+	// Cleanup Session Structure.
+	s->type = NST_FREE;
+	s->data = NULL; // no application level data assigned
+	s->disconnect_in_progress = false;
+
+
+	// Close connection	
+	close(fd);	
+	
+}//end: network_disconnect()
+
+
+int32 network_addlistener(bool v6,  const char *addr,  uint16 port){
+	SESSION *s;
+	int optval, fd;
+
+#if !defined(ENABLE_IPV6)
+	if(v6 == true){
+		 ShowError("network_addlistener(%c, '%s', %u):  this release has no IPV6 support.\n",  (v6==true?'t':'f'),  addr, port);
+		 return -1;
+	}
+#endif
+
+
+#ifdef ENABLE_IPV6
+	if(v6 == true)
+		fd = socket(AF_INET6, SOCK_STREAM, 0);
+	else
+#endif
+		fd = socket(AF_INET, SOCK_STREAM, 0);
+
+	// Error?
+	if(fd == -1){
+		ShowError("network_addlistener(%c, '%s', %u):  socket() failed (errno: %u / %s)\n",  (v6==true?'t':'f'),  addr, port,    errno, strerror(errno));
+		return -1;
+	}
+	
+	// Too many connections?
+	if(fd >= MAXCONN){
+		ShowError("network_addlistener(%c, '%s', %u):  cannot create listener, exceeds more than supported connections (%u).\n", (v6==true?'t':'f'),  addr, port, MAXCONN);
+		close(fd);
+		return -1;
+	}
+	
+	
+	s = &g_Session[fd];
+	if(s->type != NST_FREE){ // additional checks.. :)
+			ShowError("network_addlistener(%c, '%s', %u): failed, got fd #%u which is already in use in local session table?!\n", (v6==true?'t':'f'),  addr, port, fd);
+			close(fd);
+			return -1;
+	}
+	
+	
+	// Fill ip addr structs
+#ifdef ENABLE_IPV6
+	if(v6 == true){
+		memset(&s->addr.v6, 0x00, sizeof(s->addr.v6));
+		s->addr.v6.sin6_family = AF_INET6;
+		s->addr.v6.sin6_port = htons(port);
+		if(inet_pton(AF_INET6, addr, &s->addr.v6.sin6_addr) != 1){
+			ShowError("network_addlistener(%c, '%s', %u): failed to parse the given IPV6 address.\n",  (v6==true?'t':'f'),  addr, port);
+			close(fd);
+			return -1;
+		}
+		
+	}else{
+#endif
+		memset(&s->addr.v4, 0x00, sizeof(s->addr.v4));
+		s->addr.v4.sin_family = AF_INET;
+		s->addr.v4.sin_port = htons(port);
+		s->addr.v4.sin_addr.s_addr = inet_addr(addr);
+#ifdef ENABLE_IPV6
+	}
+#endif
+		 
+
+	// if OS has support for SO_REUSEADDR, apply the flag
+	// so the address could be used when there're still time_wait sockets outstanding from previous application run.
+#ifdef SO_REUSEADDR
+	optval=1;
+	setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &optval, sizeof(optval));
+#endif
+
+	// Bind
+#ifdef ENABLE_IPV6
+	if(v6 == true){
+		if( bind(fd, (struct sockaddr*)&s->addr.v6,  sizeof(s->addr.v6)) == -1) {
+			ShowError("network_addlistener(%c, '%s', %u): bind failed (errno: %u / %s)\n",  (v6==true?'t':'f'),  addr, port, errno, strerror(errno));
+			close(fd);
+			return -1;
+		}
+	}else{
+#endif
+		if( bind(fd, (struct sockaddr*)&s->addr.v4,  sizeof(s->addr.v4)) == -1) {
+            ShowError("network_addlistener(%c, '%s', %u): bind failed (errno: %u / %s)\n",  (v6==true?'t':'f'),  addr, port, errno, strerror(errno));
+			close(fd);
+			return -1;
+		}		
+#ifdef ENABLE_IPV6
+	}
+#endif
+
+	if( listen(fd, l_ListenBacklog) == -1){
+		ShowError("network_addlistener(%c, '%s', %u): listen failed (errno: %u / %s)\n",  (v6==true?'t':'f'),  addr, port, errno, strerror(errno));
+		close(fd);
+		return -1;
+	}
+		
+
+	// Set to nonblock!
+	if(_setnonblock(fd) == false){
+		ShowError("network_addlistener(%c, '%s', %u): cannot set to nonblock (errno: %u / %s)\n",  (v6==true?'t':'f'),  addr, port, errno, strerror(errno));
+		close(fd);
+		return -1;
+	}	
+
+
+	// Rgister @ evdp.
+	if( evdp_addlistener(fd, &s->evdp_data) != true){
+		ShowError("network_addlistener(%c, '%s', %u): eventdispatcher subsystem returned an error.\n",  (v6==true?'t':'f'),  addr, port);
+		close(fd);
+		return -1;
+	}
+	
+	
+	// Apply flags on Session array for this conneciton.
+	if(v6 == true)	s->v6 = true;
+	else			s->v6 = false;
+	
+	s->type = NST_LISTENER;
+	s->onRecv = _network_accept;
+
+	ShowStatus("Added Listener on '%s':%u\n", addr, port, (v6==true ? "(ipv6)":"(ipv4)") );
+
+	return fd;
+}//end: network_addlistener()
+
+
+static bool _network_connect_establishedHandler(int32 fd){
+	register SESSION *s = &g_Session[fd];
+	int val;
+	socklen_t val_len;
+	
+	if(s->type == NST_FREE)
+		return true;	// due to multiple non coalesced event notifications
+						// this can happen .. when a previous handled event has already disconnected the connection
+						// within the same cycle..
+	
+	val = -1;
+	val_len = sizeof(val);
+	getsockopt(fd, SOL_SOCKET, SO_ERROR, &val, &val_len);
+	
+	if(val != 0){
+		// :( .. cleanup session..
+		s->type = NST_FREE;
+		s->onSend = NULL;
+		s->onConnect = NULL;
+		s->onDisconnect = NULL;
+
+		evdp_remove(fd, &s->evdp_data);
+		close(fd);
+		
+		return true; // we CANT return false,
+					 // becuase the normal disconnect procedure would execute the ondisconnect handler, which we dont want .. in this case.
+	}else{
+		// ok 
+		if(s->onConnect(fd) == false) {
+			// onConnect handler has refused the connection .. 
+			// cleanup .. and ok
+			s->type = NST_FREE;
+			s->onSend = NULL;
+			s->onConnect = NULL;
+			s->onDisconnect = NULL;
+			
+			evdp_remove(fd, &s->evdp_data);
+			close(fd);
+			
+			return true; // we dnot want the ondisconnect handler to be executed, so its okay to handle this by ourself.
+		}
+		
+		// connection established ! 
+		// 
+		if( evdp_outgoingconnection_established(fd, &s->evdp_data) == false ){
+			return false; // we want the normal disconnect procedure.. with call to ondisconnect handler.
+		}
+		
+		s->onSend = NULL;
+		
+		ShowStatus("#%u connection successfull!\n", fd);	
+	}
+
+	return true;	
+}//end: _network_connect_establishedHandler()
+
+
+int32 network_connect(bool v6,
+                        const char *addr,
+                        uint16 port,
+                        const char *from_addr,
+                        uint16 from_port,
+                        bool (*onConnectionEstablishedHandler)(int32 fd),
+                        void (*onConnectionLooseHandler)(int32 fd)
+){
+	register SESSION *s;
+	int32 fd, optval, ret;
+	struct sockaddr_in ip4;
+#ifdef ENABLE_IPV6
+	struct sockaddr_in6 ip6;
+#endif
+
+#ifdef ENABLE_IPV6
+	if(v6 == true)
+		fd = socket(AF_INET6, SOCK_STREAM, 0);
+	else
+#endif
+		fd = socket(AF_INET, SOCK_STREAM, 0);
+
+#ifndef ENABLE_IPV6
+	// check..
+	if(v6 == true){
+		ShowError("network_connect(%c, '%s', %u...): tried to create an ipv6 connection, IPV6 is not supported in this release.\n", (v6==true?'t':'f'),  addr, port);
+		return -1;
+	}
+#endif
+
+	// check connection limits.
+	if(fd >= MAXCONN){
+		ShowError("network_connect(%c, '%s', %u...): cannot create new connection, exceeeds more than supported connections (%u)\n", (v6==true?'t':'f'),  addr, port );
+		close(fd);
+		return -1;
+	}
+
+	
+	// Originating IP/Port pair given ?
+	if(from_addr != NULL && *from_addr != 0){
+		//.. 
+		#ifdef SO_REUSEADDR
+	    optval=1;
+	    setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &optval, sizeof(optval));
+		#endif
+		
+		#ifdef ENABLE_IPV6
+		if(v6 == true){
+			memset(&ip6, 0x00, sizeof(ip6));
+			ip6.sin6_family = AF_INET6;
+			ip6.sin6_port = htons(from_port);
+			
+			if(inet_pton(AF_INET6, from_addr, &ip6.sin6_addr) != 1){
+				ShowError("network_connect(%c, '%s', %u...): cannot parse originating (from) IPV6 address (errno: %u / %s)\n", (v6==true?'t':'f'),  addr, port, errno, strerror(errno));
+				close(fd);
+				return -1;
+ 			}
+		
+ 			ret = bind(fd, (struct sockaddr*)&ip6, sizeof(ip6));
+		}else{
+		#endif
+			memset(&ip4, 0x00, sizeof(ip4));
+			
+			ip4.sin_family = AF_INET;
+			ip4.sin_port = htons(from_port);
+			ip4.sin_addr.s_addr = inet_addr(from_addr);
+			ret = bind(fd, (struct sockaddr*)&ip4, sizeof(ip4));
+		#ifdef ENABLE_IPV6
+		}
+		#endif
+		
+	}
+	
+
+	// Set non block
+	if(_setnonblock(fd) == false){
+		ShowError("network_connect(%c, '%s', %u...): cannot set socket to nonblocking (errno: %u / %s)\n", (v6==true?'t':'f'),  addr, port, errno, strerror(errno));
+		close(fd);
+		return -1;
+	}
+
+
+	// Create ip addr block to connect to .. 
+#ifdef ENABLE_IPV6
+	if(v6 == true){
+		memset(&ip6, 0x00, sizeof(ip6));
+		ip6.sin6_family = AF_INET6;
+		ip6.sin6_port = htons(port);
+		
+		if(inet_pton(AF_INET6, addr, &ip6.sin6_addr) != 1){
+			 ShowError("network_connect(%c, '%s', %u...): cannot parse destination IPV6 address (errno: %u / %s)\n", (v6==true?'t':'f'),  addr, port, errno, strerror(errno));
+			 close(fd);
+			 return -1;
+		}
+	
+	}else{
+#endif
+	memset(&ip4, 0x00, sizeof(ip4));
+	
+	ip4.sin_family = AF_INET;
+	ip4.sin_port = htons(port);
+	ip4.sin_addr.s_addr = inet_addr(addr);	
+#ifdef ENABLE_IPV6
+	}
+#endif
+
+
+	// Assign Session..
+	s = &g_Session[fd];
+	s->type = NST_OUTGOING;
+	s->v6 = v6;
+	s->onConnect = onConnectionEstablishedHandler;
+	s->onDisconnect = onConnectionLooseHandler;
+	s->onRecv = NULL;
+	s->onSend = _network_connect_establishedHandler;
+#ifdef ENABLE_IPV6
+	if(v6 == true)
+		memcpy(&s->addr.v6, &ip6, sizeof(ip6));
+	else
+#endif
+		memcpy(&s->addr.v4, &ip4, sizeof(ip4));
+	
+	// Register @ EVDP. as outgoing (see doc of the function)
+	if(evdp_addconnecting(fd, &s->evdp_data) == false){
+		ShowError("network_connect(%c, '%s', %u...): eventdispatcher subsystem returned an error.\n", (v6==true?'t':'f'),  addr, port);
+		
+		// cleanup session x.x.. 
+		s->type = NST_FREE;
+		s->onConnect = NULL;
+		s->onDisconnect = NULL;
+		s->onSend = NULL;
+		
+		// close, return error code.
+		close(fd);
+		return -1;
+	}
+
+
+#ifdef ENABLE_IPV6
+	if(v6 == true)
+		ret = connect(fd, (struct sockaddr*)&ip6, sizeof(ip6));
+	else
+#endif
+		ret = connect(fd, (struct sockaddr*)&ip4, sizeof(ip4));
+
+
+	// 
+	if(ret != 0 && errno != EINPROGRESS){
+		ShowWarning("network_connect(%c, '%s', %u...): connection failed (errno: %u / %s)\n", (v6==true?'t':'f'),  addr, port, errno, strerror(errno));
+		
+		// Cleanup session ..
+		s->type = NST_FREE;
+		s->onConnect = NULL;
+		s->onDisconnect = NULL;
+		s->onSend = NULL;
+		
+		// .. remove from evdp and close fd.	
+		evdp_remove(fd, &s->evdp_data);
+		close(fd);
+		return -1;
+	}
+
+
+	// ! The Info Message :~D
+	ShowStatus("network_connect fd#%u (%s:%u) in progress.. \n", fd, addr, port);
+
+return fd;	
+}//end: network_connect()
+
+
+static bool _onSend(int32 fd){
+	register SESSION *s = &g_Session[fd];
+	register netbuf buf, buf_next;
+	register uint32 szNeeded;
+	register int wLen;
+
+	if(s->type == NST_FREE)
+		return true; 	// Possible due to multipl non coalsced event notifications 
+						// so onSend gets called after disconnect caused by an previous vent. 
+						// we can ignore the call to onSend, then. 
+	
+	buf = s->write.buf;
+	while(1){
+		if(buf == NULL)
+			break;
+		
+		buf_next = buf->next;
+		
+		
+		szNeeded = (buf->dataLen - s->write.dataPos);	// using th session-local .dataPos member, due to shared write buffer support.
+		
+		// try to write.
+		wLen = write(fd, &buf->buf[s->write.dataPos],  szNeeded);
+		if(wLen == 0){
+			return false; // eof.
+		}else if(wLen == -1){
+			if(errno == EAGAIN || errno == EWOULDBLOCK)
+				return true; // dont disconnect / try again later.
+			
+			// all other errors. . 
+			return false;
+		}
+		
+		// Wrote data.. =>
+		szNeeded -= wLen;
+		if(szNeeded > 0){
+			// still data left .. 
+			// 
+			s->write.dataPos += wLen; // fix offset.
+			return true;
+		}else{
+			// this buffer has been written successfully
+			// could be returned to pool.
+			netbuffer_put(buf);
+			s->write.n_outstanding--; // When threadsafe -> Interlocked here.
+			s->write.dataPos = 0; 
+		}
+			
+			
+		buf = buf_next;
+	}
+
+	// okay,
+	// reaching this part means:
+	// while interrupted by break - 
+	// which means all buffers are written, nothing left
+	//
+	
+	s->write.buf_last = NULL;
+	s->write.buf = NULL;
+	s->write.n_outstanding = 0;
+	s->write.dataPos = 0;
+	
+	// Remove from event dispatcher (write notification)
+	//
+	evdp_writable_remove(fd, &s->evdp_data);
+			
+	return true;	
+}//end: _onSend()
+
+
+static bool _onRORecv(int32 fd){
+	register SESSION *s = &g_Session[fd];
+	register uint32	szNeeded;
+	register char *p;
+	register int rLen;
+	
+	if(s->type == NST_FREE)
+		return true;	// Possible due to multiple non coalesced events by evdp.
+						//  simply ignore this call returning positive result. 
+	
+	// Initialize p and szNeeded depending on change
+	// 
+	switch(s->read.state){
+		case NRS_WAITOP:
+			szNeeded = s->read.head_left;
+			p = ((char*)&s->read.head[0]) + (2-szNeeded);
+		break;
+
+		case NRS_WAITLEN:
+			szNeeded = s->read.head_left;
+			p = ((char*)&s->read.head[1]) + (2-szNeeded);
+		break;
+		
+		case NRS_WAITDATA:{
+			register netbuf buf = s->read.buf;
+			
+			szNeeded = (buf->dataLen - buf->dataPos);
+			p = (char*)&buf->buf[ buf->dataPos ];
+		}
+		break;	
+		
+		default: 
+			// .. the impossible gets possible .. 
+			ShowError("_onRORecv: fd #%u has unknown read.state (%d) - disconnecting\n", fd, s->read.state);
+			return false;
+		break;
+	}
+	
+	
+	// 
+	
+	rLen = read(fd, p, szNeeded);
+	if(rLen == 0){
+		// eof..
+		return false;
+	}else if(rLen == -1){
+		
+		if(errno == EAGAIN || errno == EWOULDBLOCK){
+			// try again later .. (this case shouldnt happen, because we're event trigered.. but .. sometimes it happens :)
+			return true;
+		}
+		
+		// an additional interesting case would be 
+		// EINTR, this 'could' be handled .. but:
+		//	posix says that its possible that data gets currupted during irq
+		//	or data gor read and not reported.., so we'd have a data loss..
+		//	(which shouldnt happen with stream based protocols such as tcp)
+		// its better to disonnect the client in that case.
+		
+		return false;
+	}
+	
+	//
+	// Got Data:
+	//  next action also depends on current state .. 
+	// 
+	szNeeded -= rLen;
+	switch(s->read.state){
+		case NRS_WAITOP:
+
+			if(szNeeded > 0){
+				// still data missing .. 
+				s->read.head_left = szNeeded;
+				return true; // wait for completion.
+			}else{
+				// complete .. 
+				//  next state depends on packet type.
+				
+				s->read.head[1] = ((uint16*)s->netparser_data)[ s->read.head[0] ];  // store lenght of packet by opcode head[0] to head[1]
+				
+				if(s->read.head[1] == ROPACKET_UNKNOWN){
+					// unknown packet - disconnect
+					ShowWarning("_onRORecv: fd #%u got unlnown packet 0x%04x - disconnecting.\n", fd, s->read.head[0]);
+					return false;
+				}
+				else if(s->read.head[1] == ROPACKET_DYNLEN){
+					// dynamic length
+					// next state: requrie len.
+					s->read.state = NRS_WAITLEN;
+					s->read.head_left = 2;
+					return true; //
+				}
+				else if(s->read.head[1] == 2){ 
+					// packet has no data (only opcode)
+					register netbuf buf = netbuffer_get(2); // :D whoohoo its giant! 
+					
+					NBUFW(buf, 0) = s->read.head[0]; // store opcode @ packet begin.
+					buf->dataPos = 2;
+					buf->dataLen = 2;
+					buf->next = NULL;
+					
+					// Back to initial state -> Need opcode.
+					s->read.state = NRS_WAITOP;
+					s->read.head_left = 2;
+					s->read.buf = NULL;
+					
+					// Call completion routine here.					
+					s->onPacketComplete(fd,  s->read.head[0],  2,  buf); 
+					
+					return true; // done :)
+				}
+				else{
+					// paket needs .. data ..
+					register netbuf buf = netbuffer_get( s->read.head[1] );
+					
+					NBUFW(buf, 0) = s->read.head[0]; // store opcode @ packet begin.
+					buf->dataPos = 2;
+					buf->dataLen = s->read.head[1];
+					buf->next = NULL;
+					
+					// attach buffer.
+					s->read.buf = buf;
+					
+					// set state:
+					s->read.state = NRS_WAITDATA;	
+					
+					return true;
+				}
+				
+			}//endif: szNeeded > 0 (opcode read completed?)
+			
+		break;
+		
+		
+		case NRS_WAITLEN:
+			
+			if(szNeeded > 0){
+				// incomplete .. 
+				s->read.head_left = szNeeded;
+				return true;
+			}else{
+				
+				if(s->read.head[1] == 4){
+					// packet has no data (only opcode + length)
+					register netbuf buf = netbuffer_get( 4 );
+					
+					NBUFL(buf, 0) = *((uint32*)&s->read.head[0]); // copy  Opcode + length to netbuffer using MOVL	
+					buf->dataPos = 4;
+					buf->dataLen = 4;
+					buf->next = NULL;
+					
+					// set initial state (need opcode)
+					s->read.state = NRS_WAITOP;
+					s->read.head_left = 2; 
+					s->read.buf = NULL;
+					
+					// call completion routine.
+					s->onPacketComplete(fd,  s->read.head[0],  4,  buf);
+
+					return true;					
+				}
+				else if(s->read.head[1] < 4){
+					// invalid header.
+					ShowWarning("_onRORecv: fd #%u invalid header - got packet 0x%04x, reported length < 4 - INVALID - disconnecting\n", fd, s->read.head[0]);
+					return false;
+				}
+				else{
+					// Data needed
+					// next state -> waitdata!
+					register netbuf buf = netbuffer_get( s->read.head[1] );
+					
+					NBUFL(buf, 0) = *((uint32*)&s->read.head[0]); // copy  Opcode + length to netbuffer using MOVL
+					buf->dataPos = 4;
+					buf->dataLen = s->read.head[1];
+					buf->next = NULL;
+					
+					// attach to session:
+					s->read.buf = buf;
+					s->read.state = NRS_WAITDATA;
+					
+					return true;
+				}
+				
+			}//endif: szNeeded > 0 (length read complete?)
+			
+		break;
+		
+		
+		case NRS_WAITDATA:
+
+			if(szNeeded == 0){
+				// Packet finished!
+				// compltion.
+				register netbuf buf = s->read.buf;
+				
+				// set initial state.
+				s->read.state = NRS_WAITOP;
+				s->read.head_left = 2;
+				s->read.buf = NULL;
+				
+				// Call completion routine.
+				s->onPacketComplete(fd,  NBUFW(buf, 0),  buf->dataLen,  buf);
+				
+				return true;
+			}else{
+				// still data needed 
+				s->read.buf->dataPos += rLen; 
+				
+				return true;				
+			}
+		break;
+		
+		
+		//
+		default:
+			ShowError("_onRORecv: fd #%u has unknown read.state (%d) [2] - disconnecting\n", fd, s->read.state);
+			return false;
+		break;
+	}
+	
+		
+	return false;
+}//end: _onRORecv()
+
+
+void network_send(int32 fd,  netbuf buf){
+	register SESSION *s = &g_Session[fd];
+	
+#ifdef PARANOID_CHECKS
+	if(fd >= MAXCONN){
+		ShowError("network_send: tried to attach buffer to connection idientifer #%u which is out of bounds.\n", fd);
+		_network_free_netbuf_async(buf);
+		return;
+	}
+#endif
+
+
+	if(s->type == NST_FREE)
+		return;
+	
+	// Check Max Outstanding buffers limit.
+	if( (s->write.max_outstanding > 0)	&&
+		(s->write.n_outstanding >= s->write.max_outstanding) ){
+		
+		ShowWarning("network_send: fd #%u max Outstanding buffers exceeded. - disconnecting.\n", fd);
+		network_disconnect(fd);
+		//
+		_network_free_netbuf_async(buf);
+		return;
+	}
+	
+
+	// Attach to the end:
+	buf->next = NULL;
+	if(s->write.buf_last != NULL){
+		s->write.buf_last->next = buf; 
+		s->write.buf_last = buf;
+
+	}else{
+		// currently no buffer attached.
+		s->write.buf = s->write.buf_last = buf;
+		
+		// register @ evdp for writable notification.
+		evdp_writable_add(fd, &s->evdp_data); // 
+	}
+	
+	
+	//
+	s->write.n_outstanding++;
+	
+}//end: network_send()
+
+
+void network_parser_set_ro(int32 fd,
+							int16 *packetlentable,
+							void (*onPacketCompleteProc)(int32 fd,  uint16 op,  uint16 len,  netbuf buf) 
+							){
+	register SESSION *s = &g_Session[fd];
+	register netbuf b, nb; // used for potential free attached buffers.
+	
+	if(s->type == NST_FREE)
+		return;
+	
+	s->onPacketComplete = onPacketCompleteProc;
+	
+	s->onRecv = _onRORecv; // ..
+	s->onSend = _onSend; // Using the normal generic netbuf based send function.
+		
+	s->netparser_data = packetlentable;
+	
+	// Initial State -> Need Packet OPCode.
+	s->read.state = NRS_WAITOP;
+	s->read.head_left = 2; 
+
+	
+	// Detach (if..) all buffers.
+	if(s->read.buf != NULL){
+		_network_free_netbuf_async(s->read.buf); //
+		s->read.buf = NULL;	
+	}
+	
+	if(s->write.buf != NULL){
+		b = s->write.buf;
+		while(1){
+			nb = b->next;
+			
+			_network_free_netbuf_async(b);
+			
+			b = nb;
+		}
+	
+		s->write.buf = NULL;
+		s->write.buf_last = NULL;
+		s->write.n_outstanding = 0;
+	}
+	
+	// not changing any limits on outstanding ..
+	//
+	
+}//end: network_parser_set_ro()
+