refactoring SHA dir: close channels

shadirconcurrent/main.go

@@ -28,34 +28,34 @@ func main() {
 	chan_hash, chan_path := make(chan string), make(chan string)
 
 	for i := 0; i < 100; i++ {
+		wg.Add(1)
 		go func() {
 			for path := range chan_path {
 				if h, err := sha256File(path); err != nil {
-					wg.Done()
 					log.Print("Error "+path, err)
 				} else {
 					chan_hash <- h
 				}
 			}
+			wg.Done()
 		}()
 	}
-
 	go func() {
-		for h := range chan_hash {
-			fmt.Println(h)
-			wg.Done()
-		}
+		wg.Wait()
+		close(chan_hash)
 	}()
 
-	err := filepath.Walk(os.Args[1], func(path string, info os.FileInfo, err error) error {
-		if err == nil && !info.IsDir() {
-			wg.Add(1)
-			chan_path <- path
-		}
-		return err
-	})
-	if err != nil {
-		log.Fatalln(err)
+	go func() {
+		filepath.Walk(os.Args[1], func(path string, info os.FileInfo, err error) error {
+			if err == nil && !info.IsDir() {
+				chan_path <- path
+			}
+			return err
+		})
+		close(chan_path)
+	}()
+
+	for h := range chan_hash {
+		fmt.Println(h)
 	}
-	wg.Wait()
 }