From 31731332fe45dcbd952c2075492046c079c5f35d Mon Sep 17 00:00:00 2001
From: Pawel Dziepak <pdziepak@quarnos.org>
Date: Thu, 16 Jul 2009 01:35:19 +0200
Subject: [PATCH] net: tcp_client_socket connection state routines

---
 resources/net/tcp_client_socket.cpp | 56 ++++++++++++++++++++++++++++++++-----
 resources/net/tcp_client_socket.h   | 18 ++++++++++--
 2 files changed, 65 insertions(+), 9 deletions(-)

diff --git a/resources/net/tcp_client_socket.cpp b/resources/net/tcp_client_socket.cpp
index 26c2299..c2a7921 100644
--- a/resources/net/tcp_client_socket.cpp
+++ b/resources/net/tcp_client_socket.cpp
@@ -2,7 +2,13 @@
 
 using namespace net;
 
+void poll(volatile int *value, int wait_for) {
+	while (*value != wait_for) asm volatile("nop");
+}
+
 void tcp_client_socket::connect(const ipv4_addr &addr, int port) {
+	clean();
+
 	server = addr;
 	server_port = port;
 	client_port = down->acquire_port();
@@ -10,46 +16,82 @@ void tcp_client_socket::connect(const ipv4_addr &addr, int port) {
 //	down.cast<tcp>()->listen(client_port, tcp::port_listener::method(this, &tcp_client_socket::receive));
 
 	sequence_number = 1;
-	negotiation = true;
 
 	/* TCP three-way handshake 
 	 * Part I: SYN packet */
+	state = syn_sent;
 	down.cast<tcp>()->send(addr, port, client_port, buffer::empty, tcp::tcp_syn, sequence_number++, 0);
-	
+	poll(reinterpret_cast<volatile int*>(&state), established);
 }
 
 void tcp_client_socket::receive(const ipv4_addr &addr, u16 sender_port, const buffer &data, tcp::tcp_flags flags, int seq, int ack) {
 	if (addr != server || server_port != server_port)
 		return;
 
-	if (negotiation) {
+	ack_number = seq;
+
+	if (state == syn_sent) {
 		/* In the second part of handshake we should receive SYN/ACK packet */
 		if (flags != (tcp::tcp_syn | tcp::tcp_ack) || ack != sequence_number - 1)
 			return;
-		negotiation = false;
 
 		/* TCP three-way handshake
 		 * Part III: ACK packet */
+		state = established;
 		down.cast<tcp>()->send(addr, sender_port, client_port, buffer::empty, tcp::tcp_ack, sequence_number++, seq);
 		return;
+	} else if ((state == fin_wait1 || state == fin_wait2) && flags == (tcp::tcp_fin | tcp::tcp_ack)) {
+		state = closed;
+	} else if (state == fin_wait1 && flags == tcp::tcp_ack) {
+		state = fin_wait2;
+	} else if (state == established && flags == tcp::tcp_fin) {
+		state = last_ack;
+		down.cast<tcp>()->send(server, server_port, client_port, buffer::empty, (tcp::tcp_flags)(tcp::tcp_fin | tcp::tcp_ack), sequence_number++, ack);
+	} else if (state == last_ack && flags == tcp::tcp_ack) {
+		state = closed;
+	}
+
+	if (state == established) {
+		incoming_data.push(data.copy());
 	}
 }
 
 tcp_client_socket::tcp_client_socket(p<transport_layer> tl) : client_socket(tl) { }
 tcp_client_socket::~tcp_client_socket() {
-	close();
+	clean();
 }
 
 void tcp_client_socket::write(const buffer &data) {
-	down.cast<tcp>()->send(server, server_port, client_port, data, tcp::tcp_none, sequence_number++, ack_number);
+	if (state == established)
+		down.cast<tcp>()->send(server, server_port, client_port, data, tcp::tcp_none, sequence_number++, ack_number);
 }
 
-void tcp_client_socket::read(buffer &data) { }
+void tcp_client_socket::read(buffer &data) {
+	if (state == closed || state == unknown)
+		return;
+
+	buffer buf = incoming_data.pop();
+	data.copy_data(buf);
+}
 
 void tcp_client_socket::close() {
+	state = fin_wait1;
+	down.cast<tcp>()->send(server, server_port, client_port, buffer::empty, tcp::tcp_fin, sequence_number++, 0);
+	poll(reinterpret_cast<volatile int*>(&state), closed);
+}
+
+void tcp_client_socket::clean() {
+	if (state == unknown)
+		return;
+
+	if (state != closed)
+		close();
+
 	if (client_port) {
 	//	down.cast<tcp>()->remove_listener(client_port, tcp::port_listener::method(this, &tcp_client_socket::receive));
 		down->release_port(client_port);
 		client_port = 0;
 	}
+
+	state = unknown;
 }
diff --git a/resources/net/tcp_client_socket.h b/resources/net/tcp_client_socket.h
index 874533a..889ad54 100644
--- a/resources/net/tcp_client_socket.h
+++ b/resources/net/tcp_client_socket.h
@@ -18,10 +18,24 @@ namespace net {
 		int sequence_number;
 		int ack_number;
 
-		bool negotiation;
+		enum connection_state {
+			unknown,
+			//listen,
+			syn_sent,
+			//syn_recv,
+			established,
+			fin_wait1,
+			fin_wait2,
+			//time_wait,
+			//close_wait,
+			last_ack,
+			closed
+		};
+
+		volatile connection_state state;
 
 		void receive(const ipv4_addr &addr, u16 sender_port, const buffer &data, tcp::tcp_flags, int, int);
-
+		void clean();
 	public:
 		tcp_client_socket(p<transport_layer> tl);
 		~tcp_client_socket();
-- 
2.11.4.GIT