bacnet_stack/src/bacnet/get_alarm_sum.c

/**
 * @file
 * @author Krzysztof Malorny <malornykrzysztof@gmail.com>
 * @date 2011
 * @brief GetAlarmSummary service encoding and decoding
 * @copyright SPDX-License-Identifier: GPL-2.0-or-later WITH GCC-exception-2.0
 * @section DESCRIPTION
 *
 * The GetAlarmSummary service is used by a client BACnet-user
 * to obtain a summary of "active alarms." The term "active alarm" refers
 * to BACnet standard objects that have an Event_State property whose value
 * is not equal to NORMAL and a Notify_Type property whose value is ALARM.
 * The GetEnrollmentSummary service provides a more sophisticated approach
 * with various kinds of filters
 */
#include <assert.h>

#include "bacnet/bacdcode.h"
#include "bacnet/get_alarm_sum.h"
#include "bacnet/npdu.h"

/* encode service */
int get_alarm_summary_encode_apdu(uint8_t *apdu, uint8_t invoke_id)
{
    int apdu_len = 0; /* total length of the apdu, return value */

    if (apdu) {
        apdu[0] = PDU_TYPE_CONFIRMED_SERVICE_REQUEST;
        apdu[1] = encode_max_segs_max_apdu(0, MAX_APDU);
        apdu[2] = invoke_id;
        apdu[3] = SERVICE_CONFIRMED_GET_ALARM_SUMMARY;
        apdu_len = 4;
    }

    return apdu_len;
}

/** Helper function encode the beginning of a GetAlarmSummary ACK.
 *
 * @param apdu - buffer where to put encoding
 * @param invoke_id - unique sequence number sent with the message
 *
 * @return number of bytes encoded
 */
int get_alarm_summary_ack_encode_apdu_init(uint8_t *apdu, uint8_t invoke_id)
{
    int apdu_len = 0; /* total length of the apdu, return value */

    if (apdu) {
        apdu[0] = PDU_TYPE_COMPLEX_ACK; /* complex ACK service */
        apdu[1] = invoke_id; /* original invoke id from request */
        apdu[2] = SERVICE_CONFIRMED_GET_ALARM_SUMMARY;
        apdu_len = 3;
    }

    return apdu_len;
}

/** Helper function encode the data portion of a GetAlarmSummary ACK.
 *
 * @param apdu - buffer where to put encoding
 * @param max_apdu - number of bytes available in the buffer for encoding
 * @param get_alarm_data - BACNET_GET_ALARM_SUMMARY_DATA type with data
 *
 * @return number of bytes encoded, or BACNET_STATUS_ERROR if an error.
 */
int get_alarm_summary_ack_encode_apdu_data(
    uint8_t *apdu,
    size_t max_apdu,
    const BACNET_GET_ALARM_SUMMARY_DATA *get_alarm_data)
{
    int apdu_len = 0; /* total length of the apdu, return value */

    if (!apdu) {
        apdu_len = BACNET_STATUS_ERROR;
    } else if (max_apdu >= 10) {
        /* tag 0 - Object Identifier */
        apdu_len += encode_application_object_id(
            &apdu[apdu_len], get_alarm_data->objectIdentifier.type,
            get_alarm_data->objectIdentifier.instance);
        /* tag 1 - Alarm State */
        apdu_len += encode_application_enumerated(
            &apdu[apdu_len], get_alarm_data->alarmState);
        /* tag 2 - Acknowledged Transitions */
        apdu_len += encode_application_bitstring(
            &apdu[apdu_len], &get_alarm_data->acknowledgedTransitions);
    } else {
        apdu_len = BACNET_STATUS_ABORT;
    }

    return apdu_len;
}

/** Helper function to decode the data portion of a GetAlarmSummary ACK.
 *
 * @param apdu - buffer where to put encoding
 * @param max_apdu - number of bytes available in the buffer for encoding
 * @param get_alarm_data - BACNET_GET_ALARM_SUMMARY_DATA type for data
 *
 * @return number of bytes decoded, or BACNET_STATUS_ERROR if an error.
 */
int get_alarm_summary_ack_decode_apdu_data(
    const uint8_t *apdu,
    size_t max_apdu,
    BACNET_GET_ALARM_SUMMARY_DATA *get_alarm_data)
{
    int apdu_len = 0; /* total length of the apdu, return value */
    BACNET_APPLICATION_DATA_VALUE value = { 0 };

    if (!apdu) {
        apdu_len = BACNET_STATUS_ERROR;
    } else if (max_apdu >= 10) {
        /* tag 0 - Object Identifier */
        apdu_len += bacapp_decode_application_data(
            &apdu[apdu_len], (unsigned int)(max_apdu - apdu_len), &value);
        if (value.tag == BACNET_APPLICATION_TAG_OBJECT_ID) {
            get_alarm_data->objectIdentifier = value.type.Object_Id;
        } else {
            return BACNET_STATUS_ERROR;
        }
        /* tag 1 - Alarm State */
        apdu_len += bacapp_decode_application_data(
            &apdu[apdu_len], (unsigned int)(max_apdu - apdu_len), &value);
        if (value.tag == BACNET_APPLICATION_TAG_ENUMERATED) {
            get_alarm_data->alarmState =
                (BACNET_EVENT_STATE)value.type.Enumerated;
        } else {
            return BACNET_STATUS_ERROR;
        }
        /* tag 2 - Acknowledged Transitions */
        apdu_len += bacapp_decode_application_data(
            &apdu[apdu_len], (unsigned int)(max_apdu - apdu_len), &value);
        if (value.tag == BACNET_APPLICATION_TAG_BIT_STRING) {
            get_alarm_data->acknowledgedTransitions = value.type.Bit_String;
        } else {
            return BACNET_STATUS_ERROR;
        }
    }

    return apdu_len;
}