[stable24] trigger a rescan when trying to fopen a file that exists in cache but not on disk

apps/dav/tests/unit/Connector/Sabre/FileTest.php

@@ -1151,7 +1151,7 @@ public function testGetFopenFails() {
 
 		$info = new \OC\Files\FileInfo('/test.txt', $this->getMockStorage(), null, [
 			'permissions' => \OCP\Constants::PERMISSION_ALL,
-			'type' => FileInfo::TYPE_FOLDER,
+			'type' => FileInfo::TYPE_FILE,
 		], null);
 
 		$file = new \OCA\DAV\Connector\Sabre\File($view, $info);
@@ -1172,7 +1172,7 @@ public function testGetFopenThrows() {
 
 		$info = new \OC\Files\FileInfo('/test.txt', $this->getMockStorage(), null, [
 			'permissions' => \OCP\Constants::PERMISSION_ALL,
-			'type' => FileInfo::TYPE_FOLDER,
+			'type' => FileInfo::TYPE_FILE,
 		], null);
 
 		$file = new \OCA\DAV\Connector\Sabre\File($view, $info);

lib/private/Files/Storage/Local.php

@@ -157,6 +157,9 @@ public function is_file($path) {
 	public function stat($path) {
 		$fullPath = $this->getSourcePath($path);
 		clearstatcache(true, $fullPath);
+		if (!file_exists($fullPath)) {
+			return false;
+		}
 		$statResult = @stat($fullPath);
 		if (PHP_INT_SIZE === 4 && $statResult && !$this->is_dir($path)) {
 			$filesize = $this->filesize($path);
@@ -373,8 +376,12 @@ public function copy($path1, $path2) {
 	}
 
 	public function fopen($path, $mode) {
+		$sourcePath = $this->getSourcePath($path);
+		if (!file_exists($sourcePath) && $mode === 'r') {
+			return false;
+		}
 		$oldMask = umask(022);
-		$result = fopen($this->getSourcePath($path), $mode);
+		$result = @fopen($sourcePath, $mode);
 		umask($oldMask);
 		return $result;
 	}

lib/private/Files/View.php

@@ -1007,7 +1007,17 @@ public function fopen($path, $mode) {
 			\OC::$server->getLogger()->info('Trying to open a file with a mode other than "r" or "w" can cause severe performance issues with some backends');
 		}
 
-		return $this->basicOperation('fopen', $path, $hooks, $mode);
+		$handle = $this->basicOperation('fopen', $path, $hooks, $mode);
+		if (!is_resource($handle) && $mode === 'r') {
+			// trying to read a file that isn't on disk, check if the cache is out of sync and rescan if needed
+			$mount = $this->getMount($path);
+			$internalPath = $mount->getInternalPath($this->getAbsolutePath($path));
+			$storage = $mount->getStorage();
+			if ($storage->getCache()->inCache($internalPath) && !$storage->file_exists($path)) {
+				$this->writeUpdate($storage, $internalPath);
+			}
+		}
+		return $handle;
 	}
 
 	/**

tests/lib/Files/ViewTest.php

@@ -2722,4 +2722,23 @@ public function testCacheExtension() {
 		$this->assertEquals(25, $info->getUploadTime());
 		$this->assertEquals(0, $info->getCreationTime());
 	}
+
+	public function testFopenGone() {
+		$storage = new Temporary([]);
+		$scanner = $storage->getScanner();
+		$storage->file_put_contents('foo.txt', 'bar');
+		$scanner->scan('');
+		$cache = $storage->getCache();
+
+		Filesystem::mount($storage, [], '/test/');
+		$view = new View('/test');
+
+		$storage->unlink('foo.txt');
+
+		$this->assertTrue($cache->inCache('foo.txt'));
+
+		$this->assertFalse($view->fopen('foo.txt', 'r'));
+
+		$this->assertFalse($cache->inCache('foo.txt'));
+	}
 }