From 76507afd3a449bba9cff511712392202e484cff9 Mon Sep 17 00:00:00 2001
From: Brice Jaglin <bjaglin@teads.tv>
Date: Mon, 19 May 2014 23:24:33 +0200
Subject: [PATCH] force the read of the tarSum so that sums actually get
 computed

Docker-DCO-1.1-Signed-off-by: Brice Jaglin <bjaglin@teads.tv> (github: bjaglin)
Upstream-commit: 9810da853bd890b6c963017555c3555ef9e0d842
Component: engine
---
 components/engine/server/buildfile.go | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/components/engine/server/buildfile.go b/components/engine/server/buildfile.go
index efe1869509..46f214eac7 100644
--- a/components/engine/server/buildfile.go
+++ b/components/engine/server/buildfile.go
@@ -571,6 +571,9 @@ func (b *buildFile) CmdAdd(args string) error {
 			return err
 		}
 		tarSum := utils.TarSum{Reader: r, DisableCompression: true}
+		if _, err := io.Copy(ioutil.Discard, &tarSum); err != nil {
+			return err
+		}
 		remoteHash = tarSum.Sum(nil)
 		r.Close()