Source/charon/queues/event_queue.h

   1 /**
   2  * @file event_queue.h
   3  *
   4  * @brief Interface of job_queue_t.
   5  *
   6  */
   7
   8 /*
   9  * Copyright (C) 2005 Jan Hutter, Martin Willi
  10  * Hochschule fuer Technik Rapperswil
  11  *
  12  * This program is free software; you can redistribute it and/or modify it
  13  * under the terms of the GNU General Public License as published by the
  14  * Free Software Foundation; either version 2 of the License, or (at your
  15  * option) any later version.  See <http://www.fsf.org/copyleft/gpl.txt>.
  16  *
  17  * This program is distributed in the hope that it will be useful, but
  18  * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  19  * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  20  * for more details.
  21  */
  22
  23 #ifndef EVENT_QUEUE_H_
  24 #define EVENT_QUEUE_H_
  25
  26 #include <sys/time.h>
  27
  28 #include <types.h>
  29 #include <queues/jobs/job.h>
  30
  31 typedef struct event_queue_t event_queue_t;
  32
  33 /**
  34  * @brief Event-Queue used to store timed events.
  35  *
  36  * Although the event-queue is based on a linked_list_t
  37  * all access functions are thread-save implemented.
  38  *
  39  * @ingroup queues
  40  */
  41 struct event_queue_t {
  42
  43         /**
  44          * @brief Returns number of events in queue.
  45          *
  46          * @param event_queue   calling object
  47          * @return                              number of events in queue
  48          */
  49         int (*get_count) (event_queue_t *event_queue);
  50
  51         /**
  52          * @brief Get the next job from the event-queue.
  53          *
  54          * If no event is pending, this function blocks until a job can be returned.
  55          *
  56          * @param event_queue   calling object
  57          * @param[out] job              pointer to a job pointer where to job is returned to
  58          * @return                              next job
  59          */
  60         job_t *(*get) (event_queue_t *event_queue);
  61
  62         /**
  63          * @brief Adds a event to the queue, using a relative time.
  64          *
  65          * This function is non blocking and adds a job_t at a specific time to the list.
  66          * The specific job object has to get destroyed by the thread which
  67          * removes the job.
  68          *
  69          * @param event_queue   calling object
  70          * @param[in] job               job to add to the queue (job is not copied)
  71          * @param[in] time              relative time, when the event has to get fired
  72          */
  73         void (*add_relative) (event_queue_t *event_queue, job_t *job, u_int32_t ms);
  74
  75         /**
  76          * @brief Adds a event to the queue, using an absolute time.
  77          *
  78          * This function is non blocking and adds a job_t at a specific time to the list.
  79          * The specific job object has to get destroyed by the thread which
  80          * removes the job.
  81          *
  82          * @param event_queue   calling object
  83          * @param[in]                   job job to add to the queue (job is not copied)
  84          * @param[in]                   absolute time time, when the event has to get fired
  85          */
  86         void (*add_absolute) (event_queue_t *event_queue, job_t *job, timeval_t time);
  87
  88         /**
  89          * @brief Destroys a event_queue object.
  90          *
  91          * @warning The caller of this function has to make sure
  92          * that no thread is going to add or get an event from the event_queue
  93          * after calling this function.
  94          *
  95          * @param event_queue   calling object
  96          * @returns                             always SUCCESS
  97          */
  98         void (*destroy) (event_queue_t *event_queue);
  99 };
 100
 101 /**
 102  * @brief Creates an empty event_queue
 103  *
 104  * @returns             event_queue
 105  *
 106  * @ingroup queues
 107  */
 108 event_queue_t *event_queue_create();
 109
 110 #endif /*EVENT_QUEUE_H_*/