From 301c0a6303d62ebe9b022736d816abe20924f63f Mon Sep 17 00:00:00 2001
From: Aron Fischer <github@aron.guru>
Date: Thu, 22 Dec 2016 00:34:05 +0100
Subject: [PATCH] swarm/storage: call size before seek-from-end (#3469)

---
 swarm/storage/chunker.go | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/swarm/storage/chunker.go b/swarm/storage/chunker.go
index c0f950de5..d55875369 100644
--- a/swarm/storage/chunker.go
+++ b/swarm/storage/chunker.go
@@ -483,8 +483,11 @@ func (s *LazyChunkReader) Seek(offset int64, whence int) (int64, error) {
 	case 1:
 		offset += s.off
 	case 2:
-		if s.chunk == nil {
-			return 0, fmt.Errorf("seek from the end requires rootchunk for size. call Size first")
+		if s.chunk == nil { //seek from the end requires rootchunk for size. call Size first
+			_, err := s.Size(nil)
+			if err != nil {
+				return 0, fmt.Errorf("can't get size: %v", err)
+			}
 		}
 		offset += s.chunk.Size
 	}