From 55e230ff49566e293ed62bc486b9e879731c9c14 Mon Sep 17 00:00:00 2001
From: Kenneth Skovhede <kenneth@hexad.dk>
Date: Wed, 17 May 2017 10:59:07 +0200
Subject: [PATCH] Reworked the way the `AllowWriteBuffering` flag is set to fix
 errors caused by `ContentLength` not being set.

---
 Duplicati/Library/Backend/CloudFiles/CloudFiles.cs |  7 ++++++-
 Duplicati/Library/Backend/FTP/FTPBackend.cs        |  2 +-
 Duplicati/Library/Utility/AsyncHttpRequest.cs      | 12 ++++++++----
 3 files changed, 15 insertions(+), 6 deletions(-)

diff --git a/Duplicati/Library/Backend/CloudFiles/CloudFiles.cs b/Duplicati/Library/Backend/CloudFiles/CloudFiles.cs
index 597d17c69..1b33756d3 100644
--- a/Duplicati/Library/Backend/CloudFiles/CloudFiles.cs
+++ b/Duplicati/Library/Backend/CloudFiles/CloudFiles.cs
@@ -346,8 +346,13 @@ namespace Duplicati.Library.Backend
             {
                 string fileHash = null;
 
+                long streamLen = -1;
+                try { streamLen = stream.Length; }
+                catch {}
+
+
                 Utility.AsyncHttpRequest areq = new Utility.AsyncHttpRequest(req);
-                using (System.IO.Stream s = areq.GetRequestStream())
+                using (System.IO.Stream s = areq.GetRequestStream(streamLen))
                 using (var mds = new Utility.MD5CalculatingStream(s))
                 {
                     Utility.Utility.CopyStream(stream, mds, true, m_copybuffer);
diff --git a/Duplicati/Library/Backend/FTP/FTPBackend.cs b/Duplicati/Library/Backend/FTP/FTPBackend.cs
index c39fa96db..1aea8537d 100644
--- a/Duplicati/Library/Backend/FTP/FTPBackend.cs
+++ b/Duplicati/Library/Backend/FTP/FTPBackend.cs
@@ -222,7 +222,7 @@ namespace Duplicati.Library.Backend
                 catch {}
 
                 Utility.AsyncHttpRequest areq = new Utility.AsyncHttpRequest(req);
-                using (System.IO.Stream rs = areq.GetRequestStream())
+                using (System.IO.Stream rs = areq.GetRequestStream(streamLen))
                     Utility.Utility.CopyStream(input, rs, true, m_copybuffer);
                 
                 if (m_listVerify) 
diff --git a/Duplicati/Library/Utility/AsyncHttpRequest.cs b/Duplicati/Library/Utility/AsyncHttpRequest.cs
index adbfa7853..1592cfbf5 100644
--- a/Duplicati/Library/Utility/AsyncHttpRequest.cs
+++ b/Duplicati/Library/Utility/AsyncHttpRequest.cs
@@ -95,8 +95,7 @@ namespace Duplicati.Library.Utility
                 ((HttpWebRequest)m_request).ReadWriteTimeout = System.Threading.Timeout.Infinite;
 
                 // Prevent in-memory buffering causing out-of-memory issues
-                ((HttpWebRequest)m_request).AllowReadStreamBuffering = false;
-                ((HttpWebRequest)m_request).AllowWriteStreamBuffering = false;
+                ((HttpWebRequest)m_request).AllowReadStreamBuffering = false;                    
             }
         }
 
@@ -106,7 +105,7 @@ namespace Duplicati.Library.Utility
         public WebRequest Request { get { return m_request; } }
 
         /// <summary>
-        /// Gets or sets the timeout used to guard the <see cref="GetRequestStream()"/> and <see cref="GetResponse()"/> calls
+        /// Gets or sets the timeout used to guard the <see cref="GetRequestStream(long)"/> and <see cref="GetResponse()"/> calls
         /// </summary>
         public int Timeout { get { return m_timeout; } set { m_timeout = value; } }
 
@@ -114,8 +113,13 @@ namespace Duplicati.Library.Utility
         /// Gets the request stream
         /// </summary>
         /// <returns>The request stream</returns>
-        public Stream GetRequestStream()
+        /// <param name="contentlength">The content length to use</param>
+        public Stream GetRequestStream(long contentlength = -1)
         {
+            // Prevent in-memory buffering causing out-of-memory issues
+            if (contentlength >= 0 || m_request.ContentLength >= 0)
+                ((HttpWebRequest)m_request).AllowWriteStreamBuffering = false;
+
             if (m_state == RequestStates.GetRequest)
                 return (Stream)m_asyncRequest.GetResponseOrStream();