Mqtt在另一个发布时断开连接

Question

我有2个网关（OS：yocto embedded linux）。它从云应用程序发送和接收命令。当我在网关1中单独运行mqtt应用程序时，它能够从云应用程序发送和接收命令。当我将gatway1和网关2一起运行，它们能够向云应用程序发送命令，但是当云向任何网关发送命令时，另一个网关正在断开连接。

我正在使用paho-mqtt c库3.1版

我尝试了不同的客户端ID特定主题，但没有一个工作，请给我一些帮助。

这是我的MQTT应用程序。

#include "stdio.h"
#include "stdlib.h"
#include "string.h"
#include "MQTTAsync.h"

#if !defined(WIN32)
#include <unistd.h>
#else
#include <windows.h>
#endif

#define ADDRESS     "test.mosquitto.org:1883"
#define CLIENTID    "ExampleClientPub1" //client id is UNIQUE
#define TOPIC_SUB   "pubTopic" /*2 gateways subscribed to this topic and cloud app publish to this topic */
#define TOPIC_PUB   "MQTT Examples" /*gateway send message to this topic and cloud app subscribe to this topic*/
#define PAYLOAD     "******from app2!******" /* sample payload*/
#define QOS         1
#define TIMEOUT     10000L

volatile MQTTAsync_token deliveredtoken;

int finished = 0;
MQTTAsync client;
int disc_finished = 0;
int subscribed = 0;

void connlost(void *context, char *cause)
{
    MQTTAsync_connectOptions conn_opts = MQTTAsync_connectOptions_initializer;
    int rc;

    printf("\nConnection lost\n");
    printf("     cause: %s\n", cause);

    printf("Reconnecting\n");
    conn_opts.keepAliveInterval = 20;
    conn_opts.cleansession = 1;
    if ((rc = MQTTAsync_connect(client, &conn_opts)) != MQTTASYNC_SUCCESS)
    {
        printf("Failed to start connect, return code %d\n", rc);
        finished = 1;
    }
}

void onDisconnect(void* context, MQTTAsync_successData* response)
{
    printf("Successful disconnection\n");
    finished = 1;
}

void onSend(void* context, MQTTAsync_successData* response)
{
//  MQTTAsync_disconnectOptions opts = MQTTAsync_disconnectOptions_initializer;
    int rc;

    printf("Message with token value %d delivery confirmed\n", response->token);

//  opts.onSuccess = onDisconnect;
//  opts.context = client;

//  if ((rc = MQTTAsync_disconnect(client, &opts)) != MQTTASYNC_SUCCESS)
//  {
//      printf("Failed to start sendMessage, return code %d\n", rc);
//      exit(EXIT_FAILURE);
//  }
}

void onConnectFailure(void* context, MQTTAsync_failureData* response)
{
    printf("Connect failed, rc %d\n", response ? response->code : 0);
    finished = 1;
}

void transfer() /*function  usesd for publishing*/
{
    static int i=1;
    printf("\n................................Transmitt %d................................\n",i++);
    MQTTAsync_responseOptions opts = MQTTAsync_responseOptions_initializer;
    MQTTAsync_message pubmsg = MQTTAsync_message_initializer;
    int rc;

    printf("Successful connection\n");

    opts.onSuccess = onSend;
    opts.context = client;

    pubmsg.payload = PAYLOAD;
    pubmsg.payloadlen = strlen(PAYLOAD);
    pubmsg.qos = QOS;
    pubmsg.retained = 0;
    deliveredtoken = 0;

    if ((rc = MQTTAsync_sendMessage(client, TOPIC_PUB, &pubmsg, &opts)) != MQTTASYNC_SUCCESS)
    {
        printf("Failed to start sendMessage, return code %d\n", rc);
        exit(EXIT_FAILURE);
    }
}

/************subscribe****************/

void onSubscribe(void* context, MQTTAsync_successData* response)
{
    printf("Subscribe succeeded\n");
    subscribed = 1;
}

void onSubscribeFailure(void* context, MQTTAsync_failureData* response)
{
    printf("Subscribe failed, rc %d\n", response ? response->code : 0);
    finished = 1;
}

void onConnect(void* context, MQTTAsync_successData* response)
{
    MQTTAsync client = (MQTTAsync)context;
    MQTTAsync_responseOptions opts = MQTTAsync_responseOptions_initializer;
    MQTTAsync_message pubmsg = MQTTAsync_message_initializer;
    int rc;

    printf("Successful connection\n");

    printf("Subscribing to topic %s\nfor client %s using QoS%d\n\n"
           "Press Q<Enter> to quit\n\n", TOPIC_SUB, CLIENTID, QOS);
    opts.onSuccess = onSubscribe;
    opts.onFailure = onSubscribeFailure;
    opts.context = client;

    deliveredtoken = 0;

    if ((rc = MQTTAsync_subscribe(client, TOPIC_SUB, QOS, &opts)) != MQTTASYNC_SUCCESS)
    {
        printf("Failed to start subscribe, return code %d\n", rc);
        exit(EXIT_FAILURE);
    }
}

int msgarrvd(void *context, char *topicName, int topicLen, MQTTAsync_message *message)
{
    int i;
    char* payloadptr;

    printf("Message arrived\n");
    printf("     topic: %s\n", topicName);
    printf("   message: ");

    payloadptr = message->payload;
    for(i=0; i<message->payloadlen; i++)
    {
        putchar(*payloadptr++);
    }
    putchar('\n');
    MQTTAsync_freeMessage(&message);
    MQTTAsync_free(topicName);
    return 1;
}

int main ()
{
    MQTTAsync_connectOptions conn_opts = MQTTAsync_connectOptions_initializer;
    MQTTAsync_message pubmsg = MQTTAsync_message_initializer;
    MQTTAsync_token token;
    int rc;

    MQTTAsync_create(&client, ADDRESS, CLIENTID, MQTTCLIENT_PERSISTENCE_NONE, NULL);
    MQTTAsync_setCallbacks(client, NULL, connlost, msgarrvd, NULL);

    conn_opts.keepAliveInterval = 20;
    conn_opts.cleansession = 1;
    conn_opts.onSuccess = onConnect;
    conn_opts.onFailure = onConnectFailure;
    conn_opts.context = client;

    conn_opts.keepAliveInterval = 20;
    conn_opts.cleansession = 1;
    conn_opts.onSuccess = onConnect;
    conn_opts.onFailure = onConnectFailure;
    conn_opts.context = client;
    if ((rc = MQTTAsync_connect(client, &conn_opts)) != MQTTASYNC_SUCCESS)
    {
        printf("Failed to start connect, return code %d\n", rc);
        exit(EXIT_FAILURE);
    }

    while(!subscribed)
        #if defined(WIN32)
            Sleep(100);
        #else
            usleep(10000L);
        #endif

    while(1)
    {
        sleep(1);
        transfer();
        sleep(2);
    }


}