netutils/thttpd/timers.h

/****************************************************************************
 * apps/netutils/thttpd/timers.h
 * Header file for THTTPD timers package
 *
 *   Copyright (C) 2009 Gregory Nutt. All rights reserved.
 *   Author: Gregory Nutt <gnutt@nuttx.org>
 *
 * Derived from the file of the same name in THTTPD:
 *
 *   Copyright (C) 1995,1998,1999,2000 by Jef Poskanzer <jef@mail.acme.com>.
 *   All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 ****************************************************************************/

#ifndef __APPS_NETUTILS_THTTPD_TIMERS_H
#define __APPS_NETUTILS_THTTPD_TIMERS_H

/****************************************************************************
 * Included Files
 ****************************************************************************/

#include <sys/time.h>

/****************************************************************************
 * Pre-processor Definitions
 ****************************************************************************/

#ifndef INFTIM
#  define INFTIM -1
#endif

/****************************************************************************
 * Public Types
 ****************************************************************************/

/* ClientData is a random value that tags along with a timer.  The client
 * can use it for whatever, and it gets passed to the callback when the
 * timer triggers.
 */

typedef union
{
  void *p;
  int   i;
  long  l;
} ClientData;

/* The TimerProc gets called when the timer expires.  It gets passed
 * the ClientData associated with the timer, and a timeval in case
 * it wants to schedule another timer.
 */

typedef void TimerProc(ClientData client_data, struct timeval *nowp);

/* The Timer struct. */

typedef struct TimerStruct
{
  TimerProc          *timer_proc;
  ClientData          client_data;
  long                msecs;
  int                 periodic;
  struct timeval      time;
  struct TimerStruct *prev;
  struct TimerStruct *next;
  int hash;
} Timer;

/****************************************************************************
 * Public Data
 ****************************************************************************/

extern ClientData JunkClientData;       /* For use when you don't care */

/****************************************************************************
 * Public Function Prototypes
 ****************************************************************************/

/* Initialize the timer package. */

extern void tmr_init(void);

/* Set up a timer, either periodic or one-shot.
 * Returns (Timer *)0 on errors.
 */

extern Timer *tmr_create(struct timeval *nowp, TimerProc *timer_proc,
                         ClientData client_data, long msecs, int periodic);

/* Returns a timeout in milliseconds indicating how long until the next timer
 * triggers.  You can just put the call to this routine right in your poll().
 * Returns INFTIM (-1) if no timers are pending.
 */

extern long tmr_mstimeout(struct timeval *nowp);

/* Run the list of timers.
 * Your main program needs to call this every so often.
 */

extern void tmr_run(struct timeval *nowp);

/* Deschedule a timer.  Note that non-periodic timers are automatically
 * descheduled when they run, so you don't have to call this on them.
 */

extern void tmr_cancel(Timer *timer);

/* Clean up the timers package, freeing any unused storage. */

extern void tmr_cleanup(void);

/* Cancel all timers and free storage, usually in preparation for exitting. */

extern void tmr_destroy(void);

#endif /* __APPS_NETUTILS_THTTPD_TIMERS_H */