group_membership_listener.h

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/* Copyright (c) 2017, 2024, Oracle and/or its affiliates.
 
   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License, version 2.0,
   as published by the Free Software Foundation.
 
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   as designated in a particular file or component or in included license
   documentation.  The authors of MySQL hereby grant you an additional
   permission to link the program and your derivative works with the
   separately licensed software that they have either included with
   the program or referenced in the documentation.
 
   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License, version 2.0, for more details.
 
   You should have received a copy of the GNU General Public License
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   Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301  USA */
 
#ifndef GROUP_MEMBERSHIP_LISTENER_H
#define GROUP_MEMBERSHIP_LISTENER_H
 
#include <mysql/components/service.h>
 
/**
  A service that listens for notifications about view changes or
  quorum loss.
*/
BEGIN_SERVICE_DEFINITION(group_membership_listener)
/**
  This function SHALL be called whenever there is a new view
  installed.
 
  The implementation SHALL consume the notification and
  return false on success, true on failure.
 
  The implementation MUST NOT block the caller. It MUST
  handle the notification quickly or enqueue it and deal
  with it asynchronously.
 
  @param view_id The view identifier. This must be copied
                 if the string must outlive the notification
                 lifecycle.
 
  @return false success, true on failure.
*/
DECLARE_BOOL_METHOD(notify_view_change, (const char *view_id));
 
/**
  This function SHALL be called whenever the state of a member
  changes to UNREACHABLE and that makes the system block.
 
  The implementation SHALL consume the notification and
  return false on success, true on failure.
 
  The implementation MUST NOT block the caller. It MUST
  handle the notification quickly or enqueue it and deal
  with it asynchronously.
 
  @param view_id The view identifier. This must be copied
                 if the string must outlive the notification
                 lifecycle.
 
  @return false success, true on failure.
*/
DECLARE_BOOL_METHOD(notify_quorum_loss, (const char *view_id));
 
END_SERVICE_DEFINITION(group_membership_listener)
 
#endif /* GROUP_MEMBERSHIP_LISTENER_H */