/* wm_listener.h: Windows event listener callback interface.

   Copyright 2002 Red Hat, Inc.

   Written by Philip Aston <philipa@mail.com>

This file is part of Cygwin.

This software is a copyrighted work licensed under the terms of the
Cygwin license.  Please consult the file "CYGWIN_LICENSE" for
details. */

#ifndef __WM_LISTENER_H__
#define __WM_LISTENER_H__

#include <pthread.h>
#include <windef.h>

class wm_listener
{
 protected:
  virtual ~wm_listener() {};

 public:
  virtual void wm_event (UINT uMsg, WPARAM wParam, LPARAM lParam) = 0;
};

/* Non-intrusive, thread-safe list of wm_listeners. */
class wm_listener_list
{
  struct node
  {
    wm_listener& m_listener;
    node* const m_next;

    node (wm_listener& listener, node* next)
      : m_listener (listener), m_next (next) {}
  };

  node* m_head;

  pthread_mutex_t m_mutex;

 public:
  wm_listener_list ();
  void add (wm_listener& l);
  void wm_event (UINT uMsg, WPARAM wParam, LPARAM lParam);
};

#endif /*__WM_LISTENER_H__*/