src/thttpd-2.27/timers.h

   1 /* timers.h - header file for timers package
   2 **
   3 ** Copyright © 1995,1998,1999,2000,2014 by Jef Poskanzer <jef@mail.acme.com>.
   4 ** All rights reserved.
   5 **
   6 ** Redistribution and use in source and binary forms, with or without
   7 ** modification, are permitted provided that the following conditions
   8 ** are met:
   9 ** 1. Redistributions of source code must retain the above copyright
  10 **    notice, this list of conditions and the following disclaimer.
  11 ** 2. Redistributions in binary form must reproduce the above copyright
  12 **    notice, this list of conditions and the following disclaimer in the
  13 **    documentation and/or other materials provided with the distribution.
  14 **
  15 ** THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  16 ** ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  17 ** IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  18 ** ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  19 ** FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  20 ** DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  21 ** OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  22 ** HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  23 ** LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  24 ** OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  25 ** SUCH DAMAGE.
  26 */
  27
  28 #ifndef _TIMERS_H_
  29 #define _TIMERS_H_
  30
  31 #include <sys/time.h>
  32
  33 #ifndef INFTIM
  34 #define INFTIM -1
  35 #endif /* INFTIM */
  36
  37 /* ClientData is a random value that tags along with a timer.  The client
  38 ** can use it for whatever, and it gets passed to the callback when the
  39 ** timer triggers.
  40 */
  41 typedef union {
  42     void* p;
  43     int i;
  44     long l;
  45     } ClientData;
  46
  47 extern ClientData JunkClientData;       /* for use when you don't care */
  48
  49 /* The TimerProc gets called when the timer expires.  It gets passed
  50 ** the ClientData associated with the timer, and a timeval in case
  51 ** it wants to schedule another timer.
  52 */
  53 typedef void TimerProc( ClientData client_data, struct timeval* nowP );
  54
  55 /* The Timer struct. */
  56 typedef struct TimerStruct {
  57     TimerProc* timer_proc;
  58     ClientData client_data;
  59     long msecs;
  60     int periodic;
  61     struct timeval time;
  62     struct TimerStruct* prev;
  63     struct TimerStruct* next;
  64     int hash;
  65     } Timer;
  66
  67 /* Initialize the timer package. */
  68 void tmr_init( void );
  69
  70 /* Set up a timer, either periodic or one-shot. Returns (Timer*) 0 on errors. */
  71 Timer* tmr_create(
  72     struct timeval* nowP, TimerProc* timer_proc, ClientData client_data,
  73     long msecs, int periodic );
  74
  75 /* Returns a timeout indicating how long until the next timer triggers.  You
  76 ** can just put the call to this routine right in your select().  Returns
  77 ** (struct timeval*) 0 if no timers are pending.
  78 */
  79 struct timeval* tmr_timeout( struct timeval* nowP );
  80
  81 /* Returns a timeout in milliseconds indicating how long until the next timer
  82 ** triggers.  You can just put the call to this routine right in your poll().
  83 ** Returns INFTIM (-1) if no timers are pending.
  84 */
  85 long tmr_mstimeout( struct timeval* nowP );
  86
  87 /* Run the list of timers. Your main program needs to call this every so often,
  88 ** or as indicated by tmr_timeout().
  89 */
  90 void tmr_run( struct timeval* nowP );
  91
  92 /* Reset the clock on a timer, to current time plus the original timeout. */
  93 void tmr_reset( struct timeval* nowP, Timer* timer );
  94
  95 /* Deschedule a timer.  Note that non-periodic timers are automatically
  96 ** descheduled when they run, so you don't have to call this on them.
  97 */
  98 void tmr_cancel( Timer* timer );
  99
 100 /* Clean up the timers package, freeing any unused storage. */
 101 void tmr_cleanup( void );
 102
 103 /* Cancel all timers and free storage, usually in preparation for exiting. */
 104 void tmr_term( void );
 105
 106 /* Generate debugging statistics syslog message. */
 107 void tmr_logstats( long secs );
 108
 109 #endif /* _TIMERS_H_ */