From: Zhuyifei1999 <zhuyifei1999@gmail.com>
Date: Wed, 9 Aug 2017 09:51:41 +0000 (+0000)
Subject: FileRepo: create output buffer and set ob_implicit_flush for file streaming
X-Git-Tag: 1.31.0-rc.0~2436^2
X-Git-Url: https://git.heureux-cyclage.org/?p=lhc%2Fweb%2Fwiklou.git;a=commitdiff_plain;h=0bce3d6b8c1dc3c2aa1e686f0b5bafc4fd9ba550

FileRepo: create output buffer and set ob_implicit_flush for file streaming

HHVM does not flush automatically until the output is done, unless
flush() is called. We create an output buffer so that PHP is aware
of the amount of data in the output buffer; we set ob_implicit_flush
so that, when output buffer is full and being flushed, it flushes
HHVM's buffer as well, emptying the OOM culprit.

Bug: T172851
Change-Id: I34dd1034590779ab51f197762177ad03291e3581
---

diff --git a/includes/filerepo/FileRepo.php b/includes/filerepo/FileRepo.php
index f89d96b218..dc36e50a1e 100644
--- a/includes/filerepo/FileRepo.php
+++ b/includes/filerepo/FileRepo.php
@@ -1602,9 +1602,15 @@ class FileRepo {
 		$path = $this->resolveToStoragePath( $virtualUrl );
 		$params = [ 'src' => $path, 'headers' => $headers, 'options' => $optHeaders ];
 
+		// T172851: HHVM does not flush the output properly, causing OOM
+		ob_start( NULL, 1048576 );
+		ob_implicit_flush( true );
+
 		$status = $this->newGood();
 		$status->merge( $this->backend->streamFile( $params ) );
 
+		ob_end_flush();
+
 		return $status;
 	}