add monitor logging

.gitignore

@@ -0,0 +1 @@
+cmd/relay

monitor/monitor.go

@@ -0,0 +1,34 @@
+package monitor
+
+import "github.com/golang/glog"
+
+var openPipe chan struct{}
+var closePipe chan struct{}
+
+func Init() {
+  openPipe = make(chan struct{})
+  closePipe = make(chan struct{})
+  go monitor()
+}
+
+func monitor() {
+  pipeCount := 0
+  for {
+    select {
+    case <-openPipe:
+      pipeCount++
+      glog.Infof("a new pipe opened. %v pipe(s) open", pipeCount)
+    case <-closePipe:
+      pipeCount--
+      glog.Infof("an old pipe closed. %v pipe(s) open", pipeCount)
+    }
+  }
+}
+
+func PipeOpen() {
+  openPipe <- struct{}{}
+}
+
+func PipeClose() {
+  closePipe <- struct{}{}
+}

relay.go

@@ -7,6 +7,8 @@ import (
 	"io"
 	"net"
 	"sync"
+
+	"github.com/zjiekai/relay/monitor"
 )
 
 var (
@@ -16,6 +18,7 @@ var (
 )
 
 func Start() {
+	monitor.Init()
 	ln, err := net.Listen("tcp", *laddr)
 	if err != nil {
 		return
@@ -50,7 +53,9 @@ func Pipe(src io.ReadWriteCloser, dst io.ReadWriteCloser) (int64, int64) {
 		o.Do(close)
 	}()
 
+	monitor.PipeOpen()
 	<-c
+	monitor.PipeClose()
 	return sent, received
 }
 
@@ -91,6 +96,6 @@ func handleConn(c net.Conn) {
 }
 
 func main() {
-	flag.Parse()
+  flag.Parse()
 	Start()
 }

vendor/vendor.json

@@ -8,6 +8,5 @@
 			"revision": "23def4e6c14b4da8ac2ed8007337bc5eb5007998",
 			"revisionTime": "2016-01-25T20:49:56Z"
 		}
-	],
-	"rootPath": "zjk/relay"
+	]
 }