text: /*
   * Copyright (c) 2009, Swedish Institute of Computer Science.
   * 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.
   * 3. Neither the name of the Institute nor the names of its contributors
   *    may be used to endorse or promote products derived from this software
   *    without specific prior written permission.
   *
   * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE 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 INSTITUTE 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.
   *
   * This file is part of the Contiki operating system.
   *
   */
  
  /**
   * \file
   *         Packet queue management
   * \author
   *         Adam Dunkels <adam@sics.se>
   */
  
  /**
   * \addtogroup packetqueue
   * @{
   */
  
  #include "/home/iffi/Downloads/contiki-master/core/sys/ctimer.h"
  #include "/home/iffi/Downloads/contiki-master/core/net/rime/packetqueue.h"
  
  /*---------------------------------------------------------------------------*/
  void
  packetqueue_init(struct packetqueue *q)
  {
    list_init(*q->list);
    memb_init(q->memb);
  }
  /*---------------------------------------------------------------------------*/
  static void
  remove_queued_packet(void *item)
  {
    struct packetqueue_item *i = item;
    struct packetqueue *q = i->queue;
  
    list_remove(*q->list, i);
    queuebuf_free(i->buf);
    ctimer_stop(&i->lifetimer);
    memb_free(q->memb, i);
    /*  printf("removing queued packet due to timeout\n");*/
  }
  /*---------------------------------------------------------------------------*/
  int
  packetqueue_enqueue_packetbuf(struct packetqueue *q, clock_time_t lifetime,
  			      void *ptr)
  {
    struct packetqueue_item *i;
  
    /* Allocate a memory block to hold the packet queue item. */
    i = memb_alloc(q->memb);
  
    if(i == NULL) {
      return 0;
    }
  
    /* Allocate a queuebuf and copy the contents of the packetbuf into it. */
    i->buf = queuebuf_new_from_packetbuf();
  
    if(i->buf == NULL) {
      memb_free(q->memb, i);
      return 0;
    }
  
    i->queue = q;
    i->ptr = ptr;
  
    /* Setup a ctimer that removes the packet from the queue when its
       lifetime expires. If the lifetime is zero, we do not set a
       lifetimer. */
    if(lifetime > 0) {
      ctimer_set(&i->lifetimer, lifetime, remove_queued_packet, i);
    }
  
    /* Add the item to the queue. */
    list_add(*q->list, i);
  
    return 1;
  }
  /*---------------------------------------------------------------------------*/
  struct packetqueue_item *
  packetqueue_first(struct packetqueue *q)
  {
    return list_head(*q->list);
  }
  /*---------------------------------------------------------------------------*/
  void
  packetqueue_dequeue(struct packetqueue *q)
  {
    struct packetqueue_item *i;
    
    i = list_head(*q->list);
    if(i != NULL) {
      list_remove(*q->list, i);
      queuebuf_free(i->buf);
      ctimer_stop(&i->lifetimer);
      memb_free(q->memb, i);
    }
  }
  /*---------------------------------------------------------------------------*/
  int
  packetqueue_len(struct packetqueue *q)
  {
    return list_length(*q->list);
  }
  /*---------------------------------------------------------------------------*/
  struct queuebuf *
  packetqueue_queuebuf(struct packetqueue_item *i)
  {
    if(i != NULL) {
      return i->buf;
    } else {
      return NULL;
    }
  }
  /*---------------------------------------------------------------------------*/
  void *
  packetqueue_ptr(struct packetqueue_item *i)
  {
    if(i != NULL) {
      return i->ptr;
    } else {
      return NULL;
    }
  }
  /*---------------------------------------------------------------------------*/
  /** @} */
  