From 4db00dc1847f40cddfe454158ab7023809704d8f Mon Sep 17 00:00:00 2001
From: Aaron Schulz <aschulz@wikimedia.org>
Date: Mon, 3 Feb 2014 15:06:41 -0800
Subject: [PATCH] Fixes and cleanups to FileOpBatch

* Fixed bug where operations that failed after precheck() would
  not properly update the Status. This could cause failed ops to
  be treated as successful.
* Removed special casing for 1-sized batches, this was mostly
  for Swift and is irrelevant after it was rewritten.
* Removed unused return value and fixed the docs

bug: 60318
Change-Id: I7f12ebf711bc196313745f943070f8bdb6335964
---
 includes/filebackend/FileOpBatch.php | 15 ++++-----------
 1 file changed, 4 insertions(+), 11 deletions(-)

diff --git a/includes/filebackend/FileOpBatch.php b/includes/filebackend/FileOpBatch.php
index 9fd1eb5a76..b42e140450 100644
--- a/includes/filebackend/FileOpBatch.php
+++ b/includes/filebackend/FileOpBatch.php
@@ -141,9 +141,8 @@ class FileOpBatch {
 	 * within any given sub-batch do not depend on each other.
 	 * This will abort remaining ops on failure.
 	 *
-	 * @param array $pPerformOps
+	 * @param array $pPerformOps Batches of file ops (batches use original indexes)
 	 * @param Status $status
-	 * @return bool Success
 	 */
 	protected static function runParallelBatches( array $pPerformOps, Status $status ) {
 		$aborted = false; // set to true on unexpected errors
@@ -164,12 +163,8 @@ class FileOpBatch {
 			// If attemptAsync() returns a Status, it was either due to an error
 			// or the backend does not support async ops and did it synchronously.
 			foreach ( $performOpsBatch as $i => $fileOp ) {
-				if ( !$fileOp->failed() ) { // failed => already has Status
-					// If the batch is just one operation, it's faster to avoid
-					// pipelining as that can involve creating new TCP connections.
-					$subStatus = ( count( $performOpsBatch ) > 1 )
-						? $fileOp->attemptAsync()
-						: $fileOp->attempt();
+				if ( !isset( $status->success[$i] ) ) { // didn't already fail in precheck()
+					$subStatus = $fileOp->attemptAsync();
 					if ( $subStatus->value instanceof FileBackendStoreOpHandle ) {
 						$opHandles[$i] = $subStatus->value; // deferred
 					} else {
@@ -181,7 +176,7 @@ class FileOpBatch {
 			$statuses = $statuses + $backend->executeOpHandlesInternal( $opHandles );
 			// Marshall and merge all the responses (blocking)...
 			foreach ( $performOpsBatch as $i => $fileOp ) {
-				if ( !$fileOp->failed() ) { // failed => already has Status
+				if ( !isset( $status->success[$i] ) ) { // didn't already fail in precheck()
 					$subStatus = $statuses[$i];
 					$status->merge( $subStatus );
 					if ( $subStatus->isOK() ) {
@@ -195,7 +190,5 @@ class FileOpBatch {
 				}
 			}
 		}
-
-		return $status;
 	}
 }
-- 
2.20.1