uint16_t aws_mqtt_client_connection_publish()

in source/client.c [2840:2908]

• 55 lines of code
• 6 McCabe index (conditional complexity)

uint16_t aws_mqtt_client_connection_publish(
    struct aws_mqtt_client_connection *connection,
    const struct aws_byte_cursor *topic,
    enum aws_mqtt_qos qos,
    bool retain,
    const struct aws_byte_cursor *payload,
    aws_mqtt_op_complete_fn *on_complete,
    void *userdata) {

    AWS_PRECONDITION(connection);

    if (!aws_mqtt_is_valid_topic(topic)) {
        aws_raise_error(AWS_ERROR_MQTT_INVALID_TOPIC);
        return 0;
    }

    struct publish_task_arg *arg = aws_mem_calloc(connection->allocator, 1, sizeof(struct publish_task_arg));
    if (!arg) {
        return 0;
    }

    arg->connection = connection;
    arg->topic_string = aws_string_new_from_array(connection->allocator, topic->ptr, topic->len);
    arg->topic = aws_byte_cursor_from_string(arg->topic_string);
    arg->qos = qos;
    arg->retain = retain;
    if (aws_byte_buf_init_copy_from_cursor(&arg->payload_buf, connection->allocator, *payload)) {
        goto handle_error;
    }
    arg->payload = aws_byte_cursor_from_buf(&arg->payload_buf);
    arg->on_complete = on_complete;
    arg->userdata = userdata;

    bool retry = qos == AWS_MQTT_QOS_AT_MOST_ONCE;
    uint16_t packet_id = mqtt_create_request(connection, &s_publish_send, arg, &s_publish_complete, arg, retry);

    if (packet_id == 0) {
        /* bummer, we failed to make a new request */
        AWS_LOGF_ERROR(
            AWS_LS_MQTT_CLIENT,
            "id=%p: Failed starting publish to topic " PRInSTR ",error %d (%s)",
            (void *)connection,
            AWS_BYTE_CURSOR_PRI(*topic),
            aws_last_error(),
            aws_error_name(aws_last_error()));
        goto handle_error;
    }

    AWS_LOGF_DEBUG(
        AWS_LS_MQTT_CLIENT,
        "id=%p: Starting publish %" PRIu16 " to topic " PRInSTR,
        (void *)connection,
        packet_id,
        AWS_BYTE_CURSOR_PRI(*topic));
    return packet_id;

handle_error:

    /* we know arg is valid, topic_string may or may not be valid */
    if (arg->topic_string) {
        aws_string_destroy(arg->topic_string);
    }

    aws_byte_buf_clean_up(&arg->payload_buf);

    aws_mem_release(connection->allocator, arg);

    return 0;
}