From bc8a329a74c7be4030258a6482aacb098f087913 Mon Sep 17 00:00:00 2001
From: Hucg <41573766+hcg1314@users.noreply.github.com>
Date: Mon, 18 Nov 2019 17:26:14 +0800
Subject: [PATCH] Update unixfs.go

use sync.Once instead
---
 core/coreapi/unixfs.go | 47 ++++++++++++++----------------------------
 1 file changed, 16 insertions(+), 31 deletions(-)

diff --git a/core/coreapi/unixfs.go b/core/coreapi/unixfs.go
index ab736cd63..1e4af80f6 100644
--- a/core/coreapi/unixfs.go
+++ b/core/coreapi/unixfs.go
@@ -28,42 +28,27 @@ import (
 )
 
 type UnixfsAPI CoreAPI
+
 var nilNode *core.IpfsNode
-var lock sync.Mutex
+var once sync.Once
 
 func getOrCreateNilNode() (*core.IpfsNode,error) {
-	lock.Lock()
-	defer lock.Unlock()
-
-	if nilNode != nil {
-		return nilNode,nil
-	}
-
-	node,err := core.NewNode(context.Background(),  &core.BuildCfg{
-		//TODO: need this to be true or all files
-		// hashed will be stored in memory!
-		NilRepo: true,
+	once.Do(func() {
+		if nilNode != nil {
+			return
+		}
+		node, err := core.NewNode(context.Background(), &core.BuildCfg{
+			//TODO: need this to be true or all files
+			// hashed will be stored in memory!
+			NilRepo: true,
+		})
+		if err != nil {
+			panic(err)
+		}
+		nilNode = node
 	})
 
-	if err != nil {
-		return nil, err
-	}
-
-	nilNode = node
-	return nilNode,nil
-}
-
-func CloseFakeRepo() error {
-	lock.Lock()
-	defer lock.Unlock()
-
-	if nilNode != nil {
-		if err := nilNode.Close(); err != nil {
-			return err
-		}
-		nilNode = nil
-	}
-	return nil
+	return nilNode, nil
 }
 
 // Add builds a merkledag node from a reader, adds it to the blockstore,