From b7d82f7c0192611208d66fe8d3cab34a2d56349a Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?C=C3=B4me=20Chilliet?= <come.chilliet@nextcloud.com>
Date: Mon, 4 Sep 2023 14:56:06 +0200
Subject: [PATCH] Detect aborted connection in OC\Files\View and stop writing
 data to the  output buffer
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Signed-off-by: Côme Chilliet <come.chilliet@nextcloud.com>
---
 lib/private/Files/View.php      | 10 ++++++++++
 lib/private/legacy/OC_Files.php |  3 ---
 2 files changed, 10 insertions(+), 3 deletions(-)

diff --git a/lib/private/Files/View.php b/lib/private/Files/View.php
index 95ad46ec554..ee4f01eaed4 100644
--- a/lib/private/Files/View.php
+++ b/lib/private/Files/View.php
@@ -430,6 +430,7 @@ class View {
 			$chunkSize = 524288; // 512 kB chunks
 			while (!feof($handle)) {
 				echo fread($handle, $chunkSize);
+				$this->checkConnectionStatus();
 				flush();
 			}
 			fclose($handle);
@@ -482,6 +483,7 @@ class View {
 						$len = $chunkSize;
 					}
 					echo fread($handle, $len);
+					$this->checkConnectionStatus();
 					flush();
 				}
 				return ftell($handle) - $from;
@@ -492,6 +494,14 @@ class View {
 		return false;
 	}
 
+
+	private function checkConnectionStatus(): void {
+		$connectionStatus = \connection_status();
+		if ($connectionStatus !== 0) {
+			throw new \RuntimeException("Connection lost. Status: $connectionStatus");
+		}
+	}
+
 	/**
 	 * @param string $path
 	 * @return mixed
diff --git a/lib/private/legacy/OC_Files.php b/lib/private/legacy/OC_Files.php
index 5655139b24a..92768fa8af2 100644
--- a/lib/private/legacy/OC_Files.php
+++ b/lib/private/legacy/OC_Files.php
@@ -235,9 +235,6 @@ class OC_Files {
 			OC::$server->getLogger()->logException($ex);
 			$l = \OC::$server->getL10N('lib');
 			$hint = method_exists($ex, 'getHint') ? $ex->getHint() : '';
-			if ($event && $event->getErrorMessage() !== null) {
-				$hint .= ' ' . $event->getErrorMessage();
-			}
 			\OC_Template::printErrorPage($l->t('Cannot download file'), $hint, 200);
 		}
 	}