From 35ab7f0e64316eba1966bde406f31885b61f15a8 Mon Sep 17 00:00:00 2001
From: Tim Dettrick <t.dettrick@uq.edu.au>
Date: Mon, 10 Aug 2015 11:06:45 +1000
Subject: [PATCH] Improving fopen behaviour for Swift backend

---
 apps/files_external/lib/swift.php | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/apps/files_external/lib/swift.php b/apps/files_external/lib/swift.php
index e946e7feb7..a64a02a4ed 100644
--- a/apps/files_external/lib/swift.php
+++ b/apps/files_external/lib/swift.php
@@ -354,9 +354,18 @@ class Swift extends \OC\Files\Storage\Common {
 				}
 				$tmpFile = \OCP\Files::tmpFile($ext);
 				\OC\Files\Stream\Close::registerCallback($tmpFile, array($this, 'writeBack'));
-				if ($this->file_exists($path)) {
+				// Fetch existing file if required
+				if ($mode[0] !== 'w' && $this->file_exists($path)) {
+					if ($mode[0] === 'x') {
+						// File cannot already exist
+						return false;
+					}
 					$source = $this->fopen($path, 'r');
 					file_put_contents($tmpFile, $source);
+					// Seek to end if required
+					if ($mode[0] === 'a') {
+						fseek($tmpFile, 0, SEEK_END);
+					}
 				}
 				self::$tmpFiles[$tmpFile] = $path;