Adafruit MQTT库错误连接失败

Question

Adafruit_MQTT库很棒，但我对它有一个问题。我在NodeMCU (ESP8266)的Arduino中使用它。使用示例代码，一切都很好。(TLS连接- WiFiClientSecure)。用我的方式，当我将主题直接值："sometopic/abc/adbc"输入param时，一切都是正常的。(硬编码)

//Connect successfuly when i use:
  GLB_MQTTClient = temMQTT;
  Adafruit_MQTT_Publish *temPub = new Adafruit_MQTT_Publish(GLB_MQTTClient, "pubTopic", MQTT_QOS_1);
  Adafruit_MQTT_Subscribe *temSub = new Adafruit_MQTT_Subscribe(GLB_MQTTClient, "sometopic/abc/adbc", MQTT_QOS_1);

但是，我的程序必须检查一些内容，才能从EEPROM中获得MQTT主题，这样它就不能在文件开头初始化变量时分配主题。

因此，我创建了新的指针来初始化MQTT变量的值。则库无法连接到服务器。

#include <Arduino.h>
#include <PubSubClient.h>
#include <ESP8266WiFi.h>
#include <WiFiUdp.h>
#include <Ticker.h>
#include <common.h>
#include <WiFiClientSecure.h>
#include <ArduinoJson.h>
#include "Adafruit_MQTT.h"
#include "Adafruit_MQTT_Client.h"

//Do something for wifi connection...

WiFiClientSecure GLB_secureClient;
//Init with default value, cuz the library does not have default constructor
Adafruit_MQTT_Client *GLB_MQTTClient = new Adafruit_MQTT_Client(NULL, NULL, NULL, NULL, NULL, NULL);
Adafruit_MQTT_Publish *GLB_MQTT_Publish = new Adafruit_MQTT_Publish(NULL, NULL, MQTT_QOS_1);
Adafruit_MQTT_Subscribe *GLB_MQTT_Subcribe = new Adafruit_MQTT_Subscribe(NULL,NULL,MQTT_QOS_1);

void initNormalConnection()
{
  printf("\n\nAddress of GLB_secureClient: %p\n", &GLB_secureClient);
  printf("Address of GLB_MQTTClient: %p\n", GLB_MQTTClient);
  printf("Address of GLB_MQTT_Publish: %p\n", GLB_MQTT_Publish);
  printf("Address of GLB_MQTT_Subcribe: %p\n", GLB_MQTT_Subcribe);


  GLB_secureClient = WiFiClientSecure();
  GLB_secureClient.setFingerprint(FINGER_PRINT);

  Adafruit_MQTT_Client *temMQTT = new Adafruit_MQTT_Client(&GLB_secureClient, BROKER_HOST, BROKER_PORT);

  GLB_MQTTClient = temMQTT;
  Adafruit_MQTT_Publish *temPub = new Adafruit_MQTT_Publish(GLB_MQTTClient, pubTopic, MQTT_QOS_1);
  Adafruit_MQTT_Subscribe *temSub = new Adafruit_MQTT_Subscribe(GLB_MQTTClient, subTopic, MQTT_QOS_1);

  GLB_MQTT_Publish = temPub;
  GLB_MQTT_Subcribe = temSub;
  GLB_MQTT_Subcribe->setCallback(MQTTCtrCallback);
  GLB_MQTTClient->subscribe(GLB_MQTT_Subcribe);

  printf("\n\nAddress of GLB_secureClient: %p\n", &GLB_secureClient);
  printf("Address of GLB_MQTTClient: %p\n", GLB_MQTTClient);
  printf("Address of GLB_MQTT_Publish: %p\n", GLB_MQTT_Publish);
  printf("Address of GLB_MQTT_Subcribe: %p\n", GLB_MQTT_Subcribe);

  PRINTLN("\ninitNormalConnection");
}

void MQTTConnect()
{
  int8_t ret;
  // Stop if already connected.
  PRINTLN("MQTTConnect");
  if (GLB_MQTTClient->connected())
  {
    PRINTLN("connected");
    return;
  }
  PRINTLN("not connected");

  if (stateSmartConfig || WiFi.status() != WL_CONNECTED)
  {
    return;
  }
  PRINTLN("Connecting to MQTT... ");
  uint8_t retries = 3;
  ret = GLB_MQTTClient->connect();
  PRINT("Connect MQTT result: ");
  PRINTLN(ret);
  while (ret != 0)
  { // connect will return 0 for connected
    ERR_PRINTLN(GLB_MQTTClient->connectErrorString(ret));
    DEBUG_PRINTLN("Retrying MQTT connection in 10 seconds...");
    GLB_MQTTClient->disconnect();
    delay(10000);
    retries--;
    if (retries == 0)
    {
      // basically die and wait for WDT to reset me
      return;
    }
  }
  Serial.println("MQTT Connected!");
}


void setup(){
    //Do something and check config
    initNormalConnection();
 }

void loop()
{

//do somethings

  MQTTConnect();
  GLB_MQTTClient->processPackets(10000);
  if (!GLB_MQTTClient->ping())
  {
    GLB_MQTTClient->disconnect();
  }
}

ret = GLB_MQTTClient->connect()总是使用ret = -1 (连接失败)地址输出：

Address of GLB_secureClient: 0x3ffef170 
Address of GLB_MQTTClient: 0x3fff167c 
Address of GLB_MQTT_Publish: 0x3fff17e4 
Address of GLB_MQTT_Subcribe:0x3fff17f4

Address of GLB_secureClient: 0x3ffef170 
Address of GLB_MQTTClient: 0x3fff27ac 
Address of GLB_MQTT_Publish:  0x3fff220c 
Address of GLB_MQTT_Subcribe: 0x3fff2914

问题是什么？

Answer 1

您正在了解如何使用堆。在堆上实例化两次GLB_MQTTClient、GLB_MQTT_Publish、GLB_MQTT_Subcribe，然后出现小内存泄漏，就会丢失指向声明性部分中实例类的指针。只声明一个指针，然后在initNormalConnection()中实例化一个对象。

代码摘录：

WiFiClientSecure GLB_secureClient;
//Init with default value, cuz the library does not have default constructor
Adafruit_MQTT_Client *GLB_MQTTClient;
Adafruit_MQTT_Publish *GLB_MQTT_Publish;
Adafruit_MQTT_Subscribe *GLB_MQTT_Subcribe;

void initNormalConnection()
{
  printf("\n\nAddress of GLB_secureClient: %p\n", &GLB_secureClient);
  printf("Address of GLB_MQTTClient: %p\n", GLB_MQTTClient);
  printf("Address of GLB_MQTT_Publish: %p\n", GLB_MQTT_Publish);
  printf("Address of GLB_MQTT_Subcribe: %p\n", GLB_MQTT_Subcribe);

  GLB_secureClient = WiFiClientSecure();
  GLB_secureClient.setFingerprint(FINGER_PRINT);

  GLB_MQTTClient = new Adafruit_MQTT_Client(&GLB_secureClient, BROKER_HOST, BROKER_PORT);
  GLB_MQTT_Publish = new Adafruit_MQTT_Publish(GLB_MQTTClient, pubTopic, MQTT_QOS_1);
  GLB_MQTT_Subcribe = new Adafruit_MQTT_Subscribe(GLB_MQTTClient, subTopic, MQTT_QOS_1);

  ...`