QNetworkAccessManager: HTTP download performance improvements

Better usage of move semantics with implicit sharing to avoid
detaching (=malloc/memcpy). Also some other improvements.
Download performance improvement is around 20% according
to the httpDownloadPerformance autotest.

Reviewed-by: Thiago Macieira

1 files changed, 5 insertions, 1 deletions

diff --git a/src/network/access/qnetworkaccessdebugpipebackend.cpp b/src/network/access/qnetworkaccessdebugpipebackend.cpp
index 54fcddd..2b3c128 100644
--- a/src/network/access/qnetworkaccessdebugpipebackend.cpp
+++ b/src/network/access/qnetworkaccessdebugpipebackend.cpp
@@ -155,7 +155,11 @@ void QNetworkAccessDebugPipeBackend::pushFromSocketToDownstream()
             // have read something
             buffer.resize(haveRead);
             bytesDownloaded += haveRead;
-            writeDownstreamData(buffer);
+
+            QByteDataBuffer list;
+            list.append(buffer);
+            buffer.clear(); // important because of implicit sharing!
+            writeDownstreamData(list);
         }
     }
 }