MySQL: only set the charset if the connection has succeeded

No point otherwise. But do it before trying to select the database, in
case the database name has non-US-ASCII characters.

Task-number: QTBUG-97054
Pick-to: 6.2 6.2.1
Change-Id: Iea05060bc2c046928536fffd16adf036367b07bb
Reviewed-by: Liang Qi <liang.qi@qt.io>

1 files changed, 14 insertions, 13 deletions

diff --git a/src/plugins/sqldrivers/mysql/qsql_mysql.cpp b/src/plugins/sqldrivers/mysql/qsql_mysql.cpp
index 899689af11..caf406da46 100644
--- a/src/plugins/sqldrivers/mysql/qsql_mysql.cpp
+++ b/src/plugins/sqldrivers/mysql/qsql_mysql.cpp
@@ -1304,6 +1304,15 @@ bool QMYSQLDriver::open(const QString& db,
                                       unixSocket.isNull() ? nullptr : unixSocket.toUtf8().constData(),
                                       optionFlags);
 
+    if (mysql != d->mysql) {
+        setLastError(qMakeError(tr("Unable to connect"),
+                     QSqlError::ConnectionError, d));
+        mysql_close(d->mysql);
+        d->mysql = nullptr;
+        setOpenError(true);
+        return false;
+    }
+
     // now ask the server to match the charset we selected
     if (!cs || mysql_set_character_set(d->mysql, cs->csname) != 0) {
         bool ok = false;
@@ -1319,24 +1328,16 @@ bool QMYSQLDriver::open(const QString& db,
                      mysql_character_set_name(d->mysql));
     }
 
-    if (mysql == d->mysql) {
-        if (!db.isEmpty() && mysql_select_db(d->mysql, db.toUtf8().constData())) {
-            setLastError(qMakeError(tr("Unable to open database '%1'").arg(db), QSqlError::ConnectionError, d));
-            mysql_close(d->mysql);
-            setOpenError(true);
-            return false;
-        }
-        if (reconnect)
-            mysql_options(d->mysql, MYSQL_OPT_RECONNECT, &reconnect);
-    } else {
-        setLastError(qMakeError(tr("Unable to connect"),
-                     QSqlError::ConnectionError, d));
+    if (!db.isEmpty() && mysql_select_db(d->mysql, db.toUtf8().constData())) {
+        setLastError(qMakeError(tr("Unable to open database '%1'").arg(db), QSqlError::ConnectionError, d));
         mysql_close(d->mysql);
-        d->mysql = nullptr;
         setOpenError(true);
         return false;
     }
 
+    if (reconnect)
+        mysql_options(d->mysql, MYSQL_OPT_RECONNECT, &reconnect);
+
     d->preparedQuerysEnabled = checkPreparedQueries(d->mysql);
 
 #if QT_CONFIG(thread)