Example #1
0
/**
 * @brief   Retrieves a message from a mailbox.
 * @details This variant is non-blocking, the function returns a timeout
 *          condition if the queue is empty.
 *
 * @param[in] mbp       the pointer to an initialized @p mailbox_t object
 * @param[out] msgp     pointer to a message variable for the received message
 * @return              The operation status.
 * @retval MSG_OK       if a message has been correctly fetched.
 * @retval MSG_RESET    if the mailbox has been reset.
 * @retval MSG_TIMEOUT  if the mailbox is empty and a message cannot be
 *                      fetched.
 *
 * @iclass
 */
msg_t chMBFetchI(mailbox_t *mbp, msg_t *msgp) {

  chDbgCheckClassI();
  chDbgCheck((mbp != NULL) && (msgp != NULL));

  /* If the mailbox is in reset state then returns immediately.*/
  if (mbp->reset) {
    return MSG_RESET;
  }

  /* Is there a message in queue? if so then fetch.*/
  if (chMBGetUsedCountI(mbp) > (size_t)0) {
    *msgp = *mbp->rdptr++;
    if (mbp->rdptr >= mbp->top) {
      mbp->rdptr = mbp->buffer;
    }
    mbp->cnt--;

    /* If there is a writer waiting then makes it ready.*/
    chThdDequeueNextI(&mbp->qw, MSG_OK);

    return MSG_OK;
  }

  /* No message, immediate timeout.*/
  return MSG_TIMEOUT;
}
Example #2
0
/**
 * @brief   Retrieves a message from a mailbox.
 * @details The invoking thread waits until a message is posted in the mailbox
 *          or the specified time runs out.
 *
 * @param[in] mbp       the pointer to an initialized @p mailbox_t object
 * @param[out] msgp     pointer to a message variable for the received message
 * @param[in] timeout   the number of ticks before the operation timeouts,
 *                      the following special values are allowed:
 *                      - @a TIME_IMMEDIATE immediate timeout.
 *                      - @a TIME_INFINITE no timeout.
 *                      .
 * @return              The operation status.
 * @retval MSG_OK       if a message has been correctly fetched.
 * @retval MSG_RESET    if the mailbox has been reset.
 * @retval MSG_TIMEOUT  if the operation has timed out.
 *
 * @sclass
 */
msg_t chMBFetchTimeoutS(mailbox_t *mbp, msg_t *msgp, sysinterval_t timeout) {
  msg_t rdymsg;

  chDbgCheckClassS();
  chDbgCheck((mbp != NULL) && (msgp != NULL));

  do {
    /* If the mailbox is in reset state then returns immediately.*/
    if (mbp->reset) {
      return MSG_RESET;
    }

    /* Is there a message in queue? if so then fetch.*/
    if (chMBGetUsedCountI(mbp) > (size_t)0) {
      *msgp = *mbp->rdptr++;
      if (mbp->rdptr >= mbp->top) {
        mbp->rdptr = mbp->buffer;
      }
      mbp->cnt--;

      /* If there is a writer waiting then makes it ready.*/
      chThdDequeueNextI(&mbp->qw, MSG_OK);
      chSchRescheduleS();

      return MSG_OK;
    }

    /* No message in the queue, waiting for a message to become available.*/
    rdymsg = chThdEnqueueTimeoutS(&mbp->qr, timeout);
  } while (rdymsg == MSG_OK);

  return rdymsg;
}
Example #3
0
/**
 * @brief   Posts an high priority message into a mailbox.
 * @details This variant is non-blocking, the function returns a timeout
 *          condition if the queue is full.
 *
 * @param[in] mbp       the pointer to an initialized @p mailbox_t object
 * @param[in] msg       the message to be posted on the mailbox
 * @return              The operation status.
 * @retval MSG_OK       if a message has been correctly posted.
 * @retval MSG_RESET    if the mailbox has been reset.
 * @retval MSG_TIMEOUT  if the mailbox is full and the message cannot be
 *                      posted.
 *
 * @iclass
 */
msg_t chMBPostAheadI(mailbox_t *mbp, msg_t msg) {

  chDbgCheckClassI();
  chDbgCheck(mbp != NULL);

  /* If the mailbox is in reset state then returns immediately.*/
  if (mbp->reset) {
    return MSG_RESET;
  }

  /* Is there a free message slot in queue? if so then post.*/
  if (chMBGetFreeCountI(mbp) > (size_t)0) {
    if (--mbp->rdptr < mbp->buffer) {
      mbp->rdptr = mbp->top - 1;
    }
    *mbp->rdptr = msg;
    mbp->cnt++;

    /* If there is a reader waiting then makes it ready.*/
    chThdDequeueNextI(&mbp->qr, MSG_OK);

    return MSG_OK;
  }

  /* No space, immediate timeout.*/
  return MSG_TIMEOUT;
}
Example #4
0
/**
 * @brief   Posts an high priority message into a mailbox.
 * @details The invoking thread waits until a empty slot in the mailbox becomes
 *          available or the specified time runs out.
 *
 * @param[in] mbp       the pointer to an initialized @p mailbox_t object
 * @param[in] msg       the message to be posted on the mailbox
 * @param[in] timeout   the number of ticks before the operation timeouts,
 *                      the following special values are allowed:
 *                      - @a TIME_IMMEDIATE immediate timeout.
 *                      - @a TIME_INFINITE no timeout.
 *                      .
 * @return              The operation status.
 * @retval MSG_OK       if a message has been correctly posted.
 * @retval MSG_RESET    if the mailbox has been reset.
 * @retval MSG_TIMEOUT  if the operation has timed out.
 *
 * @sclass
 */
msg_t chMBPostAheadTimeoutS(mailbox_t *mbp, msg_t msg, sysinterval_t timeout) {
  msg_t rdymsg;

  chDbgCheckClassS();
  chDbgCheck(mbp != NULL);

  do {
    /* If the mailbox is in reset state then returns immediately.*/
    if (mbp->reset) {
      return MSG_RESET;
    }

    /* Is there a free message slot in queue? if so then post.*/
    if (chMBGetFreeCountI(mbp) > (size_t)0) {
      if (--mbp->rdptr < mbp->buffer) {
        mbp->rdptr = mbp->top - 1;
      }
      *mbp->rdptr = msg;
      mbp->cnt++;

      /* If there is a reader waiting then makes it ready.*/
      chThdDequeueNextI(&mbp->qr, MSG_OK);
      chSchRescheduleS();

      return MSG_OK;
    }

    /* No space in the queue, waiting for a slot to become available.*/
    rdymsg = chThdEnqueueTimeoutS(&mbp->qw, timeout);
  } while (rdymsg == MSG_OK);

  return rdymsg;
}
Example #5
0
/**
 * @brief   Input queue write.
 * @details A byte value is written into the low end of an input queue.
 *
 * @param[in] iqp       pointer to an @p input_queue_t structure
 * @param[in] b         the byte value to be written in the queue
 * @return              The operation status.
 * @retval Q_OK         if the operation has been completed with success.
 * @retval Q_FULL       if the queue is full and the operation cannot be
 *                      completed.
 *
 * @iclass
 */
msg_t chIQPutI(input_queue_t *iqp, uint8_t b) {

  chDbgCheckClassI();

  if (chIQIsFullI(iqp))
    return Q_FULL;

  iqp->q_counter++;
  *iqp->q_wrptr++ = b;
  if (iqp->q_wrptr >= iqp->q_top)
    iqp->q_wrptr = iqp->q_buffer;

  chThdDequeueNextI(&iqp->q_waiting, Q_OK);

  return Q_OK;
}
Example #6
0
/**
 * @brief   Output queue read.
 * @details A byte value is read from the low end of an output queue.
 *
 * @param[in] oqp       pointer to an @p output_queue_t structure
 * @return              The byte value from the queue.
 * @retval Q_EMPTY      if the queue is empty.
 *
 * @iclass
 */
msg_t chOQGetI(output_queue_t *oqp) {
  uint8_t b;

  chDbgCheckClassI();

  if (chOQIsEmptyI(oqp))
    return Q_EMPTY;

  oqp->q_counter++;
  b = *oqp->q_rdptr++;
  if (oqp->q_rdptr >= oqp->q_top)
    oqp->q_rdptr = oqp->q_buffer;

  chThdDequeueNextI(&oqp->q_waiting, Q_OK);

  return b;
}
Example #7
0
/**
 * @brief   Input queue write.
 * @details A byte value is written into the low end of an input queue.
 *
 * @param[in] iqp       pointer to an @p input_queue_t structure
 * @param[in] b         the byte value to be written in the queue
 * @return              The operation status.
 * @retval Q_OK         if the operation has been completed with success.
 * @retval Q_FULL       if the queue is full and the operation cannot be
 *                      completed.
 *
 * @iclass
 */
msg_t chIQPutI(input_queue_t *iqp, uint8_t b) {

    chDbgCheckClassI();

    if (chIQIsFullI(iqp)) {
        return Q_FULL;
    }

    iqp->counter++;
    *iqp->wrptr++ = b;
    if (iqp->wrptr >= iqp->top) {
        iqp->wrptr = iqp->buffer;
    }

    chThdDequeueNextI(&iqp->waiting, Q_OK);

    return Q_OK;
}
Example #8
0
/**
 * @brief   Output queue read.
 * @details A byte value is read from the low end of an output queue.
 *
 * @param[in] oqp       pointer to an @p output_queue_t structure
 * @return              The byte value from the queue.
 * @retval Q_EMPTY      if the queue is empty.
 *
 * @iclass
 */
msg_t chOQGetI(output_queue_t *oqp) {
    uint8_t b;

    chDbgCheckClassI();

    if (chOQIsEmptyI(oqp)) {
        return Q_EMPTY;
    }

    oqp->counter++;
    b = *oqp->rdptr++;
    if (oqp->rdptr >= oqp->top) {
        oqp->rdptr = oqp->buffer;
    }

    chThdDequeueNextI(&oqp->waiting, Q_OK);

    return (msg_t)b;
}