Make BytesSyncLogger's implementation details internal.

Provide NewBytesSyncLogger that returns an opaque data structure.
Automatically start up the logging loop goroutine in NewBytesSyncLogger.

client/lib/util.go

@@ -10,7 +10,6 @@ const (
 )
 
 type BytesLogger interface {
-	Log()
 	AddOutbound(int)
 	AddInbound(int)
 }
@@ -18,50 +17,55 @@ type BytesLogger interface {
 // Default BytesLogger does nothing.
 type BytesNullLogger struct{}
 
-func (b BytesNullLogger) Log()                   {}
 func (b BytesNullLogger) AddOutbound(amount int) {}
 func (b BytesNullLogger) AddInbound(amount int)  {}
 
 // BytesSyncLogger uses channels to safely log from multiple sources with output
 // occuring at reasonable intervals.
 type BytesSyncLogger struct {
-	OutboundChan chan int
-	InboundChan  chan int
-	Outbound     int
-	Inbound      int
-	OutEvents    int
-	InEvents     int
+	outboundChan chan int
+	inboundChan  chan int
 }
 
-func (b *BytesSyncLogger) Log() {
-	var amount int
+// NewBytesSyncLogger returns a new BytesSyncLogger and starts it loggin.
+func NewBytesSyncLogger() *BytesSyncLogger {
+	b := &BytesSyncLogger{
+		outboundChan: make(chan int, 5),
+		inboundChan:  make(chan int, 5),
+	}
+	go b.log()
+	return b
+}
+
+func (b *BytesSyncLogger) log() {
+	var outbound, inbound, outEvents, inEvents int
 	output := func() {
 		log.Printf("Traffic Bytes (in|out): %d | %d -- (%d OnMessages, %d Sends)",
-			b.Inbound, b.Outbound, b.InEvents, b.OutEvents)
-		b.Outbound = 0
-		b.OutEvents = 0
-		b.Inbound = 0
-		b.InEvents = 0
+			inbound, outbound, inEvents, outEvents)
+		outbound = 0
+		outEvents = 0
+		inbound = 0
+		inEvents = 0
 	}
 	last := time.Now()
 	for {
 		select {
-		case amount = <-b.OutboundChan:
-			b.Outbound += amount
-			b.OutEvents++
+		case amount := <-b.outboundChan:
+			outbound += amount
+			outEvents++
 			if time.Since(last) > time.Second*LogTimeInterval {
 				last = time.Now()
 				output()
 			}
-		case amount = <-b.InboundChan:
-			b.Inbound += amount
-			b.InEvents++
+		case amount := <-b.inboundChan:
+			inbound += amount
+			inEvents++
 			if time.Since(last) > time.Second*LogTimeInterval {
 				last = time.Now()
 				output()
 			}
 		case <-time.After(time.Second * LogTimeInterval):
-			if b.InEvents > 0 || b.OutEvents > 0 {
+			if inEvents > 0 || outEvents > 0 {
 				output()
 			}
 		}
@@ -69,9 +73,9 @@ func (b *BytesSyncLogger) Log() {
 }
 
 func (b *BytesSyncLogger) AddOutbound(amount int) {
-	b.OutboundChan <- amount
+	b.outboundChan <- amount
 }
 
 func (b *BytesSyncLogger) AddInbound(amount int) {
-	b.InboundChan <- amount
+	b.inboundChan <- amount
 }