Bug #33334 mysqltest_embedded crashes when disconnecting before reap.

Before breaking the connection we have to check that there's no query
  executing at the moment. Otherwise it can lead to crash in embedded server.

client/mysqltest.c

@@ -542,6 +542,17 @@ static int do_send_query(struct st_connection *cn, const char *q, int q_len,
   return 0;
 }
 
+static void wait_query_thread_end(struct st_connection *con)
+{
+  if (!con->query_done)
+  {
+    pthread_mutex_lock(&con->mutex);
+    while (!con->query_done)
+      pthread_cond_wait(&con->cond, &con->mutex);
+    pthread_mutex_unlock(&con->mutex);
+  }
+}
+
 #else /*EMBEDDED_LIBRARY*/
 
 #define do_send_query(cn,q,q_len,flags) mysql_send_query(&cn->mysql, q, q_len)
@@ -3939,7 +3950,14 @@ void do_close_connection(struct st_command *command)
       con->mysql.net.vio = 0;
     }
   }
-#endif
+#else
+  /*
+    As query could be still executed in a separate theread
+    we need to check if the query's thread was finished and probably wait
+    (embedded-server specific)
+  */
+  wait_query_thread_end(con);
+#endif /*EMBEDDED_LIBRARY*/
   if (con->stmt)
     mysql_stmt_close(con->stmt);
   con->stmt= 0;
@@ -4229,6 +4247,9 @@ void do_connect(struct st_command *command)
           (int) (sizeof(connections)/sizeof(struct st_connection)));
   }
 
+#ifdef EMBEDDED_LIBRARY
+  con_slot->query_done= 1;
+#endif
   if (!mysql_init(&con_slot->mysql))
     die("Failed on mysql_init()");
   if (opt_compress || con_compress)
@@ -5716,16 +5737,11 @@ void run_query_normal(struct st_connection *cn, struct st_command *command,
   }
 #ifdef EMBEDDED_LIBRARY
   /*
-   Here we handle 'reap' command, so we need to check if the
-   query's thread was finished and probably wait
+    Here we handle 'reap' command, so we need to check if the
+    query's thread was finished and probably wait
   */
   else if (flags & QUERY_REAP_FLAG)
-  {
-    pthread_mutex_lock(&cn->mutex);
-    while (!cn->query_done)
-      pthread_cond_wait(&cn->cond, &cn->mutex);
-    pthread_mutex_unlock(&cn->mutex);
-  }
+    wait_query_thread_end(cn);
 #endif /*EMBEDDED_LIBRARY*/
   if (!(flags & QUERY_REAP_FLAG))
     DBUG_VOID_RETURN;

mysql-test/r/flush.result

@@ -72,3 +72,4 @@ flush tables with read lock;
 unlock tables;
 drop table t1, t2;
 set session low_priority_updates=default;
+select benchmark(200, (select sin(1))) > 1000;

mysql-test/t/flush.test

@@ -164,4 +164,13 @@ drop table t1, t2;
 
 set session low_priority_updates=default;
 
+#
+# Bug #33334 mysqltest_embedded crashes when disconnecting before reap
+#
+
+connect (con1,localhost,root,,);
+send select benchmark(200, (select sin(1))) > 1000;
+disconnect con1;
+connection default;
+
 # End of 5.0 tests