all: improve the method of import for internal packages

1. Change directory structure and Makefile to let GOPATH=`pwd`, so wherever the project directory is, just use make to build.

src/frp/utils/broadcast/broadcast_test.go

@@ -0,0 +1,63 @@
+package broadcast
+
+import (
+	"sync"
+	"testing"
+	"time"
+)
+
+var (
+	totalNum int = 5
+	succNum  int = 0
+	mutex    sync.Mutex
+)
+
+func TestBroadcast(t *testing.T) {
+	b := NewBroadcast()
+	if b == nil {
+		t.Errorf("New Broadcast error, nil return")
+	}
+	defer b.Close()
+
+	var wait sync.WaitGroup
+	wait.Add(totalNum)
+	for i := 0; i < totalNum; i++ {
+		go worker(b, &wait)
+	}
+
+	time.Sleep(1e6 * 20)
+	msg := "test"
+	b.In() <- msg
+
+	wait.Wait()
+	if succNum != totalNum {
+		t.Errorf("TotalNum %d, FailNum(timeout) %d", totalNum, totalNum-succNum)
+	}
+}
+
+func worker(b *Broadcast, wait *sync.WaitGroup) {
+	defer wait.Done()
+	msgChan := b.Reg()
+
+	// exit if nothing got in 2 seconds
+	timeout := make(chan bool, 1)
+	go func() {
+		time.Sleep(time.Duration(2) * time.Second)
+		timeout <- true
+	}()
+
+	select {
+	case item := <-msgChan:
+		msg := item.(string)
+		if msg == "test" {
+			mutex.Lock()
+			succNum++
+			mutex.Unlock()
+		} else {
+			break
+		}
+
+	case <-timeout:
+		break
+	}
+}