From 0b8c40aa61e899edb3e563b7771e3d7927d6e859 Mon Sep 17 00:00:00 2001
From: Sergey Matveev <stargrave@stargrave.org>
Date: Tue, 6 Oct 2015 11:27:11 +0300
Subject: [PATCH] Refactored and corrected client's network data reading

---
 client.go      | 44 +++++++++++++++++++++++++++-----------------
 client_test.go |  4 ++--
 daemon_test.go |  1 +
 room_test.go   |  7 ++++---
 4 files changed, 34 insertions(+), 22 deletions(-)

diff --git a/client.go b/client.go
index 95dd93f..9bcaf30 100644
--- a/client.go
+++ b/client.go
@@ -27,8 +27,11 @@ import (
 )
 
 const (
-	CRLF    = "\x0d\x0a"
-	BufSize = 1380
+	BufSize = 1500
+)
+
+var (
+	CRLF []byte = []byte{'\x0d', '\x0a'}
 )
 
 type Client struct {
@@ -59,34 +62,41 @@ func NewClient(hostname *string, conn net.Conn) *Client {
 // splits messages by CRLF and send them to Daemon gorouting for processing
 // it futher. Also it can signalize that client is unavailable (disconnected).
 func (client *Client) Processor(sink chan<- ClientEvent) {
-	var bufNet []byte
-	buf := make([]byte, 0)
-	log.Println(client, "New client")
 	sink <- ClientEvent{client, EventNew, ""}
+	log.Println(client, "New client")
+	buf := make([]byte, BufSize*2)
+	var n int
+	var prev int
+	var i int
+	var err error
 	for {
-		bufNet = make([]byte, BufSize)
-		_, err := client.conn.Read(bufNet)
+		if prev == BufSize {
+			log.Println(client, "buffer size exceeded, kicking him")
+			sink <- ClientEvent{client, EventDel, ""}
+			client.conn.Close()
+			break
+		}
+		n, err = client.conn.Read(buf[prev:])
 		if err != nil {
 			sink <- ClientEvent{client, EventDel, ""}
 			break
 		}
-		bufNet = bytes.TrimRight(bufNet, "\x00")
-		buf = append(buf, bufNet...)
-		if !bytes.HasSuffix(buf, []byte(CRLF)) {
+		prev += n
+	CheckMore:
+		i = bytes.Index(buf[:prev], CRLF)
+		if i == -1 {
 			continue
 		}
-		for _, msg := range bytes.Split(buf[:len(buf)-2], []byte(CRLF)) {
-			if len(msg) > 0 {
-				sink <- ClientEvent{client, EventMsg, string(msg)}
-			}
-		}
-		buf = []byte{}
+		sink <- ClientEvent{client, EventMsg, string(buf[:i])}
+		copy(buf, buf[i+2:prev])
+		prev -= (i + 2)
+		goto CheckMore
 	}
 }
 
 // Send message as is with CRLF appended.
 func (client *Client) Msg(text string) {
-	client.conn.Write([]byte(text + CRLF))
+	client.conn.Write(append([]byte(text), CRLF...))
 }
 
 // Send message from server. It has ": servername" prefix.
diff --git a/client_test.go b/client_test.go
index 38f8808..3735e1f 100644
--- a/client_test.go
+++ b/client_test.go
@@ -47,10 +47,10 @@ func (conn *TestingConn) Read(b []byte) (n int, err error) {
 	if msg == "" {
 		return 0, conn
 	}
-	for n, bt := range []byte(msg + CRLF) {
+	for n, bt := range append([]byte(msg), CRLF...) {
 		b[n] = bt
 	}
-	return len(msg), nil
+	return len(msg)+2, nil
 }
 
 type MyAddr struct{}
diff --git a/daemon_test.go b/daemon_test.go
index 3db72cb..efdb39f 100644
--- a/daemon_test.go
+++ b/daemon_test.go
@@ -91,6 +91,7 @@ func TestRegistrationWorkflow(t *testing.T) {
 
 	conn.inbound <- "AWAY"
 	conn.inbound <- "UNEXISTENT CMD"
+	<-conn.outbound
 	if r := <-conn.outbound; r != ":foohost 421 meinick UNEXISTENT :Unknown command\r\n" {
 		t.Fatal("reply for unexistent command", r)
 	}
diff --git a/room_test.go b/room_test.go
index d5bf411..d94e8d4 100644
--- a/room_test.go
+++ b/room_test.go
@@ -56,8 +56,8 @@ func TestTwoUsers(t *testing.T) {
 	go client1.Processor(events)
 	go client2.Processor(events)
 
-	conn1.inbound <- "NICK nick1\r\nUSER foo1 bar1 baz1 :Long name1\r\n"
-	conn2.inbound <- "NICK nick2\r\nUSER foo2 bar2 baz2 :Long name2\r\n"
+	conn1.inbound <- "NICK nick1\r\nUSER foo1 bar1 baz1 :Long name1"
+	conn2.inbound <- "NICK nick2\r\nUSER foo2 bar2 baz2 :Long name2"
 	for i := 0; i < 6; i++ {
 		<-conn1.outbound
 		<-conn2.outbound
@@ -105,6 +105,7 @@ func TestTwoUsers(t *testing.T) {
 	conn1.inbound <- "PRIVMSG nick2 :Hello"
 	conn1.inbound <- "PRIVMSG #foo :world"
 	conn1.inbound <- "NOTICE #foo :world"
+	<-conn2.outbound
 	if r := <-conn2.outbound; r != ":nick1!foo1@someclient PRIVMSG nick2 :Hello\r\n" {
 		t.Fatal("first message", r)
 	}
@@ -127,7 +128,7 @@ func TestJoin(t *testing.T) {
 	client := NewClient(&host, conn)
 	go client.Processor(events)
 
-	conn.inbound <- "NICK nick2\r\nUSER foo2 bar2 baz2 :Long name2\r\n"
+	conn.inbound <- "NICK nick2\r\nUSER foo2 bar2 baz2 :Long name2"
 	for i := 0; i < 6; i++ {
 		<-conn.outbound
 	}
-- 
2.44.0