1 files changed, 52 insertions, 0 deletions
diff --git a/lib/private/DB/MySqlTools.php b/lib/private/DB/MySqlTools.php
new file mode 100644
index 00000000000..3413be43417
--- /dev/null
+++ b/lib/private/DB/MySqlTools.php
@@ -0,0 +1,52 @@
+<?php
+
+/**
+ * SPDX-FileCopyrightText: 2017 ownCloud GmbH
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+namespace OC\DB;
+
+use OCP\IDBConnection;
+
+/**
+ * Various MySQL specific helper functions.
+ */
+class MySqlTools {
+	/**
+	 * @param IDBConnection $connection
+	 * @return bool
+	 */
+	public function supports4ByteCharset(IDBConnection $connection) {
+		$variables = ['innodb_file_per_table' => 'ON'];
+		if (!$this->isMariaDBWithLargePrefix($connection)) {
+			$variables['innodb_file_format'] = 'Barracuda';
+			$variables['innodb_large_prefix'] = 'ON';
+		}
+
+		foreach ($variables as $var => $val) {
+			$result = $connection->executeQuery("SHOW VARIABLES LIKE '$var'");
+			$row = $result->fetch();
+			$result->closeCursor();
+			if ($row === false) {
+				return false;
+			}
+			if (strcasecmp($row['Value'], $val) !== 0) {
+				return false;
+			}
+		}
+		return true;
+	}
+
+	protected function isMariaDBWithLargePrefix(IDBConnection $connection) {
+		$result = $connection->executeQuery('SELECT VERSION()');
+		$row = strtolower($result->fetchColumn());
+		$result->closeCursor();
+
+		if ($row === false) {
+			return false;
+		}
+
+		return str_contains($row, 'maria') && version_compare($row, '10.3', '>=')
+			|| !str_contains($row, 'maria') && version_compare($row, '8.0', '>=');
+	}
+}