evq_timer.h

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// This component produces timer events. On Symbian, it should be implementable based on RTimer. On a POSIX system, an implementation based on pthread_cond_timedwait should work just fine. In fact, the same implementation may just work with Open C on Symbian.

// Note that this API is not intended to be thread safe, even though some worker thread(s) may be used internally.

#ifndef __EVQ_TIMER_H__
#define __EVQ_TIMER_H__

#include "common/evq_event.h"

// 0 value indicates no error.
// Other error codes are POSIX style.
typedef MAYBE_ERROR_RTYPE (TimerCallback)(int errCode, void* user_data MAYBE_ERROR_PARAM);

// Only one timer request per Timer object may be outstanding at any one time.
typedef struct {
  Event event;
  EventQueue* queue;
  pthread_t worker;
  pthread_mutex_t mutex;
  pthread_cond_t cond;
  int running; // worker thread is running
  int active; // timer is active
  struct timespec* time;
  TimerCallback* callback;
  void* user_data;
} Timer;

// Initializes the passed timer object.
// You must specify the event queue of the thread in which any callbacks are to be made.
// In the Symbian OS implementation the "queue" argument is pointless, and may be passed as NULL.
void timer_init(EventQueue* queue, Timer* timer);

// Makes a timer request. Expiration is at the specified absolute
// time.
// time:: Expiration time is not copied, and hence must persist until
//        completion.
void timer_at(Timer* timer, struct timespec* time, TimerCallback* callback, void* user_data);

// Cancels any outstanding timer request.
// No harm in calling this if there is no outstanding request.
void timer_cancel(Timer* timer);

// Frees the resources associated with the timer object.
void timer_close(Timer* timer);

#endif //  __EVQ_TIMER_H__

/**

evq_timer.h

Copyright 2009 Helsinki Institute for Information Technology (HIIT)
and the authors. All rights reserved.

Authors: Tero Hasu <tero.hasu@hut.fi>

Permission is hereby granted, free of charge, to any person
obtaining a copy of this software and associated documentation files
(the "Software"), to deal in the Software without restriction,
including without limitation the rights to use, copy, modify, merge,
publish, distribute, sublicense, and/or sell copies of the Software,
and to permit persons to whom the Software is furnished to do so,
subject to the following conditions:

The above copyright notice and this permission notice shall be
included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.

 **/