void
_mongoc_metadata_cleanup (void)
{
   _free_system_info (&gMongocMetadata);
   _free_driver_info (&gMongocMetadata);
   _free_platform_string (&gMongocMetadata);
}
void
_mongoc_handshake_cleanup (void)
{
   _free_system_info (_mongoc_handshake_get ());
   _free_driver_info (_mongoc_handshake_get ());
   _free_platform_string (_mongoc_handshake_get ());

   bson_mutex_destroy (&gHandshakeLock);
}