Microsoft Azure IoTHub client AMQP transport

Dependents:   sht15_remote_monitoring RobotArmDemo iothub_client_sample_amqp iothub_client_sample_amqp ... more

This library implements the AMQP transport for Microsoft Azure IoTHub client. The code is replicated from https://github.com/Azure/azure-iot-sdks

iothubtransport_amqp_connection.c

Committer:
AzureIoTClient
Date:
2018-09-11
Revision:
56:8704100b3b54
Parent:
53:e21e1e88460f

File content as of revision 56:8704100b3b54:

// Copyright (c) Microsoft. All rights reserved.
// Licensed under the MIT license. See LICENSE file in the project root for full license information.

#include <stdlib.h>
#include <limits.h>
#include "internal/iothubtransport_amqp_connection.h"
#include "azure_c_shared_utility/optimize_size.h"
#include "azure_c_shared_utility/gballoc.h"
#include "azure_c_shared_utility/strings.h"
#include "azure_c_shared_utility/uniqueid.h"
#include "azure_uamqp_c/sasl_mechanism.h"
#include "azure_uamqp_c/saslclientio.h"
#include "azure_uamqp_c/sasl_mssbcbs.h"
#include "azure_uamqp_c/connection.h"
#include "azure_c_shared_utility/xlogging.h"

#define RESULT_OK                            0
#define DEFAULT_INCOMING_WINDOW_SIZE         UINT_MAX
#define DEFAULT_OUTGOING_WINDOW_SIZE         100
#define SASL_IO_OPTION_LOG_TRACE             "logtrace"
#define DEFAULT_UNIQUE_ID_LENGTH             40

typedef struct AMQP_CONNECTION_INSTANCE_TAG
{
    STRING_HANDLE iothub_fqdn;
    XIO_HANDLE underlying_io_transport;
    CBS_HANDLE cbs_handle;
    CONNECTION_HANDLE connection_handle;
    SESSION_HANDLE session_handle;
    XIO_HANDLE sasl_io;
    SASL_MECHANISM_HANDLE sasl_mechanism;
    bool has_cbs;
    bool has_sasl_mechanism;
    bool is_trace_on;
    AMQP_CONNECTION_STATE current_state;
    ON_AMQP_CONNECTION_STATE_CHANGED on_state_changed_callback;
    const void* on_state_changed_context;
    uint32_t svc2cl_keep_alive_timeout_secs;
    double cl2svc_keep_alive_send_ratio;
} AMQP_CONNECTION_INSTANCE;


DEFINE_ENUM_STRINGS(AMQP_CONNECTION_STATE, AMQP_CONNECTION_STATE_VALUES);


static int create_sasl_components(AMQP_CONNECTION_INSTANCE* instance)
{
    int result;
    SASL_MECHANISM_HANDLE sasl_mechanism;
    XIO_HANDLE sasl_io;

    // Codes_SRS_IOTHUBTRANSPORT_AMQP_CONNECTION_09_012: [`instance->sasl_mechanism` shall be created using saslmechanism_create()]
    if ((sasl_mechanism = saslmechanism_create(saslmssbcbs_get_interface(), NULL)) == NULL)
    {
        // Codes_SRS_IOTHUBTRANSPORT_AMQP_CONNECTION_09_013: [If saslmechanism_create() fails, amqp_connection_create() shall fail and return NULL]
        LogError("Failed creating the SASL mechanism (saslmechanism_create failed)");
        result = __FAILURE__;
    }
    else
    {
        // Codes_SRS_IOTHUBTRANSPORT_AMQP_CONNECTION_09_014: [A SASLCLIENTIO_CONFIG shall be set with `instance->underlying_io_transport` and `instance->sasl_mechanism`]
        SASLCLIENTIO_CONFIG sasl_client_config;
        sasl_client_config.sasl_mechanism = sasl_mechanism;
        sasl_client_config.underlying_io = instance->underlying_io_transport;

        // Codes_SRS_IOTHUBTRANSPORT_AMQP_CONNECTION_09_015: [`instance->sasl_io` shall be created using xio_create() passing saslclientio_get_interface_description() and the SASLCLIENTIO_CONFIG instance]
        if ((sasl_io = xio_create(saslclientio_get_interface_description(), &sasl_client_config)) == NULL)
        {
            // Codes_SRS_IOTHUBTRANSPORT_AMQP_CONNECTION_09_016: [If xio_create() fails, amqp_connection_create() shall fail and return NULL]
            LogError("Failed creating the SASL I/O (xio_create failed)");
            saslmechanism_destroy(sasl_mechanism);
            result = __FAILURE__;
        }
        // Codes_SRS_IOTHUBTRANSPORT_AMQP_CONNECTION_09_017: [The sasl_io "logtrace" option shall be set using xio_setoption(), passing `instance->is_trace_on`]
        else if (xio_setoption(sasl_io, SASL_IO_OPTION_LOG_TRACE, (const void*)&instance->is_trace_on) != RESULT_OK)
        {
            LogError("Failed setting the SASL I/O logging trace option (xio_setoption failed)");
            xio_destroy(sasl_io);
            saslmechanism_destroy(sasl_mechanism);
            result = __FAILURE__;
        }
        else
        {
            instance->sasl_mechanism = sasl_mechanism;
            instance->sasl_io = sasl_io;
            result = RESULT_OK;
        }
    }

    return result;
}

static void update_state(AMQP_CONNECTION_INSTANCE* instance, AMQP_CONNECTION_STATE new_state)
{
    if (new_state != instance->current_state)
    {
        AMQP_CONNECTION_STATE previous_state = instance->current_state;
        instance->current_state = new_state;

        if (instance->on_state_changed_callback != NULL)
        {
            instance->on_state_changed_callback(instance->on_state_changed_context, previous_state, new_state);
        }
    }
}

static void on_connection_io_error(void* context)
{
    // Codes_SRS_IOTHUBTRANSPORT_AMQP_CONNECTION_09_022: [If the connection calls back with an I/O error, `instance->on_state_changed_callback` shall be invoked if set passing code AMQP_CONNECTION_STATE_ERROR and `instance->on_state_changed_context`]
    update_state((AMQP_CONNECTION_INSTANCE*)context, AMQP_CONNECTION_STATE_ERROR);
}

static void on_connection_state_changed(void* context, CONNECTION_STATE new_connection_state, CONNECTION_STATE previous_connection_state)
{
    (void)previous_connection_state;

    AMQP_CONNECTION_INSTANCE* instance = (AMQP_CONNECTION_INSTANCE*)context;

    // Codes_SRS_IOTHUBTRANSPORT_AMQP_CONNECTION_09_063: [If `on_connection_state_changed` is called back, `instance->on_state_changed_callback` shall be invoked, if defined]
    if (new_connection_state == CONNECTION_STATE_START)
    {
        // connection is using x509 authentication.
        // At this point uamqp's connection only raises CONNECTION_STATE_START when using X509 auth.
        // So that should be all we expect to consider the amqp_connection_handle opened.
        if (instance->has_cbs == false || instance->has_sasl_mechanism == false)
        {
            update_state(instance, AMQP_CONNECTION_STATE_OPENED);
        }
    }
    // Codes_SRS_IOTHUBTRANSPORT_AMQP_CONNECTION_09_064: [If `on_connection_state_changed` new state is CONNECTION_STATE_OPENED, `instance->on_state_changed_callback` shall be invoked with state AMQP_CONNECTION_STATE_OPENED]
    else if (new_connection_state == CONNECTION_STATE_OPENED)
    {
        update_state(instance, AMQP_CONNECTION_STATE_OPENED);
    }
    // Codes_SRS_IOTHUBTRANSPORT_AMQP_CONNECTION_09_065: [If `on_connection_state_changed` new state is CONNECTION_STATE_END, `instance->on_state_changed_callback` shall be invoked with state AMQP_CONNECTION_STATE_CLOSED]
    else if (new_connection_state == CONNECTION_STATE_END)
    {
        update_state(instance, AMQP_CONNECTION_STATE_CLOSED);
    }
    // Codes_SRS_IOTHUBTRANSPORT_AMQP_CONNECTION_09_071: [If `on_connection_state_changed` new state is CONNECTION_STATE_ERROR or CONNECTION_STATE_DISCARDING, `instance->on_state_changed_callback` shall be invoked with state AMQP_CONNECTION_STATE_ERROR]
    else if (new_connection_state == CONNECTION_STATE_ERROR || new_connection_state == CONNECTION_STATE_DISCARDING)
    {
        update_state(instance, AMQP_CONNECTION_STATE_ERROR);
    }
}

static void on_cbs_open_complete(void* context, CBS_OPEN_COMPLETE_RESULT open_complete_result)
{
    (void)context;
    (void)open_complete_result;
    if (open_complete_result != CBS_OPEN_OK)
    {
        LogError("CBS open failed");
    }
}

static void on_cbs_error(void* context)
{
    (void)context;
    LogError("CBS Error occured");
}

static int create_connection_handle(AMQP_CONNECTION_INSTANCE* instance)
{
    int result;
    char* unique_container_id = NULL;
    XIO_HANDLE connection_io_transport;

    // Codes_SRS_IOTHUBTRANSPORT_AMQP_CONNECTION_09_007: [If `instance->sasl_io` is defined it shall be used as parameter `xio` in connection_create2()]
    if (instance->sasl_io != NULL)
    {
        connection_io_transport = instance->sasl_io;
    }
    // Codes_SRS_IOTHUBTRANSPORT_AMQP_CONNECTION_09_018: [If `instance->sasl_io` is not defined, `instance->underlying_io_transport` shall be used as parameter `xio` in connection_create2()]
    else
    {
        connection_io_transport = instance->underlying_io_transport;
    }

    if ((unique_container_id = (char*)malloc(sizeof(char) * DEFAULT_UNIQUE_ID_LENGTH + 1)) == NULL)
    {
        result = __LINE__;
        LogError("Failed creating the AMQP connection (failed creating unique ID container)");
    }
    else
    {
        memset(unique_container_id, 0, sizeof(char) * DEFAULT_UNIQUE_ID_LENGTH + 1);

        if (UniqueId_Generate(unique_container_id, DEFAULT_UNIQUE_ID_LENGTH) != UNIQUEID_OK)
        {
            result = __FAILURE__;
            LogError("Failed creating the AMQP connection (UniqueId_Generate failed)");
        }
        // Codes_SRS_IOTHUBTRANSPORT_AMQP_CONNECTION_09_019: [`instance->connection_handle` shall be created using connection_create2(), passing the `connection_underlying_io`, `instance->iothub_host_fqdn` and an unique string as container ID]
        // Codes_SRS_IOTHUBTRANSPORT_AMQP_CONNECTION_09_020: [connection_create2() shall also receive `on_connection_state_changed` and `on_connection_error` callback functions]
        else if ((instance->connection_handle = connection_create2(connection_io_transport, STRING_c_str(instance->iothub_fqdn), unique_container_id, NULL, NULL, on_connection_state_changed, (void*)instance, on_connection_io_error, (void*)instance)) == NULL)
        {
            // Codes_SRS_IOTHUBTRANSPORT_AMQP_CONNECTION_09_021: [If connection_create2() fails, amqp_connection_create() shall fail and return NULL]
            result = __FAILURE__;
            LogError("Failed creating the AMQP connection (connection_create2 failed)");
        }
        else if (connection_set_idle_timeout(instance->connection_handle, 1000 * instance->svc2cl_keep_alive_timeout_secs) != RESULT_OK)
        {
            // Codes_SRS_IOTHUBTRANSPORT_AMQP_CONNECTION_09_074: [If connection_set_idle_timeout() fails, amqp_connection_create() shall fail and return NULL]
            result = __FAILURE__;
            LogError("Failed creating the AMQP connection (connection_set_idle_timeout failed)");
        }
        else if (connection_set_remote_idle_timeout_empty_frame_send_ratio(instance->connection_handle, instance->cl2svc_keep_alive_send_ratio) != RESULT_OK)
        {
            // Codes_SRS_IOTHUBTRANSPORT_AMQP_CONNECTION_99_001: [If connection_set_remote_idle_timeout_empty_frame_send_ratio fails, amqp_connection_create() shall fail and return NULL]
            result = __FAILURE__;
            LogError("Failed creating the AMQP connection (connection_set_remote_idle_timeout_empty_frame_send_ratio)");
        }
        else
        {
            // Codes_SRS_IOTHUBTRANSPORT_AMQP_CONNECTION_09_023: [The connection tracing shall be set using connection_set_trace(), passing `instance->is_trace_on`]
            connection_set_trace(instance->connection_handle, instance->is_trace_on);

            result = RESULT_OK;
        }
    }

    if (unique_container_id != NULL)
    {
        free(unique_container_id);
    }

    return result;
}

static int create_session_handle(AMQP_CONNECTION_INSTANCE* instance)
{
    int result;

    // Codes_SRS_IOTHUBTRANSPORT_AMQP_CONNECTION_09_024: [`instance->session_handle` shall be created using session_create(), passing `instance->connection_handle`]
    if ((instance->session_handle = session_create(instance->connection_handle, NULL, NULL)) == NULL)
    {
        // Codes_SRS_IOTHUBTRANSPORT_AMQP_CONNECTION_09_025: [If session_create() fails, amqp_connection_create() shall fail and return NULL]
        result = __FAILURE__;
        LogError("Failed creating the AMQP connection (connection_create2 failed)");
    }
    else
    {
        // Codes_SRS_IOTHUBTRANSPORT_AMQP_CONNECTION_09_026: [The `instance->session_handle` incoming window size shall be set as UINT_MAX using session_set_incoming_window()]
        if (session_set_incoming_window(instance->session_handle, (uint32_t)DEFAULT_INCOMING_WINDOW_SIZE) != 0)
        {
            LogError("Failed to set the AMQP session incoming window size.");
        }

        // Codes_SRS_IOTHUBTRANSPORT_AMQP_CONNECTION_09_027: [The `instance->session_handle` outgoing window size shall be set as 100 using session_set_outgoing_window()]
        if (session_set_outgoing_window(instance->session_handle, DEFAULT_OUTGOING_WINDOW_SIZE) != 0)
        {
            LogError("Failed to set the AMQP session outgoing window size.");
        }

        result = RESULT_OK;
    }

    return result;
}

static int create_cbs_handle(AMQP_CONNECTION_INSTANCE* instance)
{
    int result;

    // Codes_SRS_IOTHUBTRANSPORT_AMQP_CONNECTION_09_029: [`instance->cbs_handle` shall be created using cbs_create()`]
    if ((instance->cbs_handle = cbs_create(instance->session_handle)) == NULL)
    {
        // Codes_SRS_IOTHUBTRANSPORT_AMQP_CONNECTION_09_030: [If cbs_create() fails, amqp_connection_create() shall fail and return NULL]
        result = __FAILURE__;
        LogError("Failed to create the CBS connection.");
    }
    // Codes_SRS_IOTHUBTRANSPORT_AMQP_CONNECTION_09_031: [`instance->cbs_handle` shall be opened using `cbs_open_async`]
    else if (cbs_open_async(instance->cbs_handle, on_cbs_open_complete, instance->cbs_handle, on_cbs_error, instance->cbs_handle) != RESULT_OK)
    {
        // Codes_SRS_IOTHUBTRANSPORT_AMQP_CONNECTION_09_032: [If cbs_open() fails, amqp_connection_create() shall fail and return NULL]
        result = __FAILURE__;
        LogError("Failed to open the connection with CBS.");
    }
    else
    {
        result = RESULT_OK;
    }

    return result;
}


// Public APIS:

void amqp_connection_destroy(AMQP_CONNECTION_HANDLE conn_handle)
{
    // Codes_SRS_IOTHUBTRANSPORT_AMQP_CONNECTION_09_035: [If `conn_handle` is NULL, amqp_connection_destroy() shall fail and return]
    if (conn_handle != NULL)
    {
        AMQP_CONNECTION_INSTANCE* instance = (AMQP_CONNECTION_INSTANCE*)conn_handle;

        // Codes_SRS_IOTHUBTRANSPORT_AMQP_CONNECTION_09_036: [amqp_connection_destroy() shall destroy `instance->cbs_handle` if set using cbs_destroy()]
        if (instance->cbs_handle != NULL)
        {
            cbs_destroy(instance->cbs_handle);
        }

        // Codes_SRS_IOTHUBTRANSPORT_AMQP_CONNECTION_09_037: [amqp_connection_destroy() shall destroy `instance->session_handle` if set using session_destroy()]
        if (instance->session_handle != NULL)
        {
            session_destroy(instance->session_handle);
        }

        // Codes_SRS_IOTHUBTRANSPORT_AMQP_CONNECTION_09_067: [amqp_connection_destroy() shall destroy `instance->connection_handle` if set using connection_destroy()]
        if (instance->connection_handle != NULL)
        {
            connection_destroy(instance->connection_handle);
        }

        // Codes_SRS_IOTHUBTRANSPORT_AMQP_CONNECTION_09_038: [amqp_connection_destroy() shall destroy `instance->sasl_io` if set using xio_destroy()]
        if (instance->sasl_io != NULL)
        {
            xio_destroy(instance->sasl_io);
        }

        // Codes_SRS_IOTHUBTRANSPORT_AMQP_CONNECTION_09_039: [amqp_connection_destroy() shall destroy `instance->sasl_mechanism` if set using saslmechanism_destroy()]
        if (instance->sasl_mechanism != NULL)
        {
            saslmechanism_destroy(instance->sasl_mechanism);
        }

        // Codes_SRS_IOTHUBTRANSPORT_AMQP_CONNECTION_09_059: [amqp_connection_destroy() shall destroy `instance->iothub_host_fqdn` if set using STRING_delete()]
        if (instance->iothub_fqdn != NULL)
        {
            STRING_delete(instance->iothub_fqdn);
        }

        // Codes_SRS_IOTHUBTRANSPORT_AMQP_CONNECTION_09_040: [amqp_connection_destroy() shall free the memory allocated for the connection instance]
        free(instance);
    }
}

AMQP_CONNECTION_HANDLE amqp_connection_create(AMQP_CONNECTION_CONFIG* config)
{
    AMQP_CONNECTION_HANDLE result;

    // Codes_SRS_IOTHUBTRANSPORT_AMQP_CONNECTION_09_001: [If `config` is NULL, amqp_connection_create() shall fail and return NULL]
    if (config == NULL)
    {
        result = NULL;
        LogError("amqp_connection_create failed (config is NULL)");
    }
    // Codes_SRS_IOTHUBTRANSPORT_AMQP_CONNECTION_09_002: [If `config->iothub_host_fqdn` is NULL, amqp_connection_create() shall fail and return NULL]
    else if (config->iothub_host_fqdn == NULL)
    {
        result = NULL;
        LogError("amqp_connection_create failed (config->iothub_host_fqdn is NULL)");
    }
    // Codes_SRS_IOTHUBTRANSPORT_AMQP_CONNECTION_09_003: [If `config->underlying_io_transport` is NULL, amqp_connection_create() shall fail and return NULL]
    else if (config->underlying_io_transport == NULL)
    {
        result = NULL;
        LogError("amqp_connection_create failed (config->underlying_io_transport is NULL)");
    }
    else
    {
        AMQP_CONNECTION_INSTANCE* instance;

        // Codes_SRS_IOTHUBTRANSPORT_AMQP_CONNECTION_09_057: [amqp_connection_create() shall allocate memory for an instance of the connection state]
        if ((instance = (AMQP_CONNECTION_INSTANCE*)malloc(sizeof(AMQP_CONNECTION_INSTANCE))) == NULL)
        {
            // Codes_SRS_IOTHUBTRANSPORT_AMQP_CONNECTION_09_058: [If malloc() fails, amqp_connection_create() shall fail and return NULL]
            result = NULL;
            LogError("amqp_connection_create failed (malloc failed)");
        }
        else
        {
            memset(instance, 0, sizeof(AMQP_CONNECTION_INSTANCE));

            // Codes_SRS_IOTHUBTRANSPORT_AMQP_CONNECTION_09_005: [A copy of `config->iothub_host_fqdn` shall be saved on `instance->iothub_host_fqdn`]
            if ((instance->iothub_fqdn = STRING_construct(config->iothub_host_fqdn)) == NULL)
            {
                // Codes_SRS_IOTHUBTRANSPORT_AMQP_CONNECTION_09_066: [If STRING_construct() fails, amqp_connection_create() shall fail and return NULL]
                result = NULL;
                LogError("amqp_connection_create failed (STRING_construct failed)");
            }
            else
            {
                // Codes_SRS_IOTHUBTRANSPORT_AMQP_CONNECTION_09_006: [`config->underlying_io_transport` shall be saved on `instance->underlying_io_transport`]
                instance->underlying_io_transport = config->underlying_io_transport;
                // Codes_SRS_IOTHUBTRANSPORT_AMQP_CONNECTION_09_008: [`config->is_trace_on` shall be saved on `instance->is_trace_on`]
                instance->is_trace_on = config->is_trace_on;
                // Codes_SRS_IOTHUBTRANSPORT_AMQP_CONNECTION_09_060: [`config->on_state_changed_callback` shall be saved on `instance->on_state_changed_callback`]
                instance->on_state_changed_callback = config->on_state_changed_callback;
                // Codes_SRS_IOTHUBTRANSPORT_AMQP_CONNECTION_09_061: [`config->on_state_changed_context` shall be saved on `instance->on_state_changed_context`]
                instance->on_state_changed_context = config->on_state_changed_context;
                instance->has_sasl_mechanism = config->create_sasl_io;
                instance->has_cbs = config->create_cbs_connection;

                instance->svc2cl_keep_alive_timeout_secs = (uint32_t)config->svc2cl_keep_alive_timeout_secs;
                instance->cl2svc_keep_alive_send_ratio = (double)config->cl2svc_keep_alive_send_ratio;

                instance->current_state = AMQP_CONNECTION_STATE_CLOSED;

                // Codes_SRS_IOTHUBTRANSPORT_AMQP_CONNECTION_09_011: [If `config->create_sasl_io` is true or `config->create_cbs_connection` is true, amqp_connection_create() shall create SASL I/O]
                if ((config->create_sasl_io || config->create_cbs_connection) && create_sasl_components(instance) != RESULT_OK)
                {
                    result = NULL;
                    LogError("amqp_connection_create failed (failed creating the SASL components)");
                }
                else if (create_connection_handle(instance) != RESULT_OK)
                {
                    result = NULL;
                    LogError("amqp_connection_create failed (failed creating the AMQP connection)");
                }
                else if (create_session_handle(instance) != RESULT_OK)
                {
                    result = NULL;
                    LogError("amqp_connection_create failed (failed creating the AMQP session)");
                }
                // Codes_SRS_IOTHUBTRANSPORT_AMQP_CONNECTION_09_028: [Only if `config->create_cbs_connection` is true, amqp_connection_create() shall create and open the CBS_HANDLE]
                else if (config->create_cbs_connection && create_cbs_handle(instance) != RESULT_OK)
                {
                    result = NULL;
                    LogError("amqp_connection_create failed (failed creating the CBS handle)");
                }
                else
                {
                    // Codes_SRS_IOTHUBTRANSPORT_AMQP_CONNECTION_09_034: [If no failures occur, amqp_connection_create() shall return the handle to the connection state]
                    result = (AMQP_CONNECTION_HANDLE)instance;
                }
            }

            if (result == NULL)
            {
                amqp_connection_destroy((AMQP_CONNECTION_HANDLE)instance);
            }
        }
    }

    return result;
}

void amqp_connection_do_work(AMQP_CONNECTION_HANDLE conn_handle)
{
    // Codes_SRS_IOTHUBTRANSPORT_AMQP_CONNECTION_09_041: [If `conn_handle` is NULL, amqp_connection_do_work() shall fail and return]
    if (conn_handle != NULL)
    {
        AMQP_CONNECTION_INSTANCE* instance = (AMQP_CONNECTION_INSTANCE*)conn_handle;

        // Codes_SRS_IOTHUBTRANSPORT_AMQP_CONNECTION_09_042: [connection_dowork() shall be invoked passing `instance->connection_handle`]
        connection_dowork(instance->connection_handle);
    }
}

int amqp_connection_get_session_handle(AMQP_CONNECTION_HANDLE conn_handle, SESSION_HANDLE* session_handle)
{
    int result;

    // Codes_SRS_IOTHUBTRANSPORT_AMQP_CONNECTION_09_043: [If `conn_handle` is NULL, amqp_connection_get_session_handle() shall fail and return __FAILURE__]
    if (conn_handle == NULL)
    {
        result = __FAILURE__;
        LogError("amqp_connection_get_session_handle failed (conn_handle is NULL)");
    }
    // Codes_SRS_IOTHUBTRANSPORT_AMQP_CONNECTION_09_044: [If `session_handle` is NULL, amqp_connection_get_session_handle() shall fail and return __FAILURE__]
    else if (session_handle == NULL)
    {
        result = __FAILURE__;
        LogError("amqp_connection_get_session_handle failed (session_handle is NULL)");
    }
    else
    {
        AMQP_CONNECTION_INSTANCE* instance = (AMQP_CONNECTION_INSTANCE*)conn_handle;

        // Codes_SRS_IOTHUBTRANSPORT_AMQP_CONNECTION_09_045: [`session_handle` shall be set to point to `instance->session_handle`]
        *session_handle = instance->session_handle;

        // Codes_SRS_IOTHUBTRANSPORT_AMQP_CONNECTION_09_046: [amqp_connection_get_session_handle() shall return success code 0]
        result = RESULT_OK;
    }

    return result;
}

int amqp_connection_get_cbs_handle(AMQP_CONNECTION_HANDLE conn_handle, CBS_HANDLE* cbs_handle)
{
    int result;

    // Codes_SRS_IOTHUBTRANSPORT_AMQP_CONNECTION_09_047: [If `conn_handle` is NULL, amqp_connection_get_cbs_handle() shall fail and return __FAILURE__]
    if (conn_handle == NULL)
    {
        result = __FAILURE__;
        LogError("amqp_connection_get_cbs_handle failed (conn_handle is NULL)");
    }
    // Codes_SRS_IOTHUBTRANSPORT_AMQP_CONNECTION_09_048: [If `cbs_handle` is NULL, amqp_connection_get_cbs_handle() shall fail and return __FAILURE__]
    else if (cbs_handle == NULL)
    {
        result = __FAILURE__;
        LogError("amqp_connection_get_cbs_handle failed (parameter cbs_handle is NULL)");
    }
    else
    {
        AMQP_CONNECTION_INSTANCE* instance = (AMQP_CONNECTION_INSTANCE*)conn_handle;

        // Codes_SRS_IOTHUBTRANSPORT_AMQP_CONNECTION_09_049: [If `instance->cbs_handle` is NULL, amqp_connection_get_cbs_handle() shall fail and return __FAILURE__]
        if (instance->cbs_handle == NULL)
        {
            result = __FAILURE__;
            LogError("amqp_connection_get_cbs_handle failed (there is not a cbs_handle to be returned)");
        }
        else
        {
            // Codes_SRS_IOTHUBTRANSPORT_AMQP_CONNECTION_09_050: [`cbs_handle` shall be set to point to `instance->cbs_handle`]
            *cbs_handle = instance->cbs_handle;

            // Codes_SRS_IOTHUBTRANSPORT_AMQP_CONNECTION_09_051: [amqp_connection_get_cbs_handle() shall return success code 0]
            result = RESULT_OK;
        }
    }

    return result;
}

int amqp_connection_set_logging(AMQP_CONNECTION_HANDLE conn_handle, bool is_trace_on)
{
    int result;

    // Codes_SRS_IOTHUBTRANSPORT_AMQP_CONNECTION_09_052: [If `conn_handle` is NULL, amqp_connection_set_logging() shall fail and return __FAILURE__]
    if (conn_handle == NULL)
    {
        result = __FAILURE__;
        LogError("amqp_connection_set_logging failed (conn_handle is NULL)");
    }
    else
    {
        AMQP_CONNECTION_INSTANCE* instance = (AMQP_CONNECTION_INSTANCE*)conn_handle;

        // Codes_SRS_IOTHUBTRANSPORT_AMQP_CONNECTION_09_053: [`instance->is_trace_on` shall be set to `is_trace_on`]
        instance->is_trace_on = is_trace_on;

        // Codes_SRS_IOTHUBTRANSPORT_AMQP_CONNECTION_09_054: [Tracing on `instance->sasl_io` shall be set to `instance->is_trace_on` if the value has changed]
        if (instance->sasl_io != NULL &&
            xio_setoption(instance->sasl_io, SASL_IO_OPTION_LOG_TRACE, (const void*)&instance->is_trace_on) != RESULT_OK)
        {
            // Codes_SRS_IOTHUBTRANSPORT_AMQP_CONNECTION_09_072: [If xio_setoption() fails, amqp_connection_set_logging() shall fail and return __FAILURE__]
            result = __FAILURE__;
            LogError("amqp_connection_set_logging failed (xio_setoption() failed)");
        }
        else
        {
            // Codes_SRS_IOTHUBTRANSPORT_AMQP_CONNECTION_09_055: [Tracing on `instance->connection_handle` shall be set to `instance->is_trace_on` if the value has changed]
            connection_set_trace(instance->connection_handle, instance->is_trace_on);

            // Codes_SRS_IOTHUBTRANSPORT_AMQP_CONNECTION_09_056: [amqp_connection_set_logging() shall return success code 0]
            result = RESULT_OK;
        }
    }

    return result;
}