PubSubClient ESP32 disconnected while receive message - c++

Question

I create a project to receive message from MQTT. My full code is here
https://github.com/kamshory/OTP-Mini/blob/main/Server/Server.ino
WiFiClient espClient;
PubSubClient client(espClient);
void setup()
{
char * mqttServer = "192.168.1.3";
client.setServer(mqttServer, 1883);
client.setCallback(mqttCallback);
}
void mqttCallback(const char* topic, byte* payload, unsigned int length) {
Serial.print("Message arrived on topic: ");
Serial.print(topic);
Serial.print("Message: ");
char * mqttTopic = "sms";
String messageTemp;
for (int i = 0; i < length; i++) {
Serial.print((char)payload[i]);
messageTemp += (char)payload[i];
}
Serial.println();
// Feel free to add more if statements to control more GPIOs with MQTT
// If a message is received on the topic esp32/output, you check if the message is either "on" or "off".
// Changes the output state according to the message
if (String(topic) == String(mqttTopic)) {
}
}
void mqttReconnect() {
Serial.print("WiFi status = ");
Serial.println(WiFi.status());
char * clientId = "php";
char * mqttUsername = "user";
char * mqttPassword = "pass";
char * mqttTopic = "sms";
// Loop until we're reconnected
while (!client.connected()) {
Serial.print("Attempting MQTT connection ");
// Attempt to connect
if (client.connect(clientId, mqttUsername, mqttPassword)) {
Serial.println("connected");
// Subscribe
boolean sub = client.subscribe("sms");
Serial.println(sub);
} else {
Serial.print("failed, rc=");
Serial.print(client.state());
Serial.println(" try again in 5 seconds");
// Wait 5 seconds before retrying
delay(5000);
}
}
}
When ESP32 publish a message in a topic, the message is received by subscriber (I create the subscriber with Java). But when it try to receive the message with callback, the client is disconnected.
I try to debug with edit library on file PubSubClient.cpp
boolean PubSubClient::loop() {
if (connected()) {
unsigned long t = millis();
if ((t - lastInActivity > MQTT_KEEPALIVE*1000UL) || (t - lastOutActivity > MQTT_KEEPALIVE*1000UL)) {
if (pingOutstanding) {
this->_state = MQTT_CONNECTION_TIMEOUT;
_client->stop();
return false;
} else {
buffer[0] = MQTTPINGREQ;
buffer[1] = 0;
_client->write(buffer,2);
lastOutActivity = t;
lastInActivity = t;
pingOutstanding = true;
}
}
if (_client->available()) {
uint8_t llen;
uint16_t len = readPacket(&llen);
uint16_t msgId = 0;
uint8_t *payload;
if (len > 0) {
lastInActivity = t;
uint8_t type = buffer[0]&0xF0;
if (type == MQTTPUBLISH) {
if (callback) {
uint16_t tl = (buffer[llen+1]<<8)+buffer[llen+2]; /* topic length in bytes */
memmove(buffer+llen+2,buffer+llen+3,tl); /* move topic inside buffer 1 byte to front */
buffer[llen+2+tl] = 0; /* end the topic as a 'C' string with \x00 */
char *topic = (char*) buffer+llen+2;
// msgId only present for QOS>0
if ((buffer[0]&0x06) == MQTTQOS1) {
msgId = (buffer[llen+3+tl]<<8)+buffer[llen+3+tl+1];
payload = buffer+llen+3+tl+2;
callback(topic,payload,len-llen-3-tl-2);
buffer[0] = MQTTPUBACK;
buffer[1] = 2;
buffer[2] = (msgId >> 8);
buffer[3] = (msgId & 0xFF);
_client->write(buffer,4);
lastOutActivity = t;
} else {
payload = buffer+llen+3+tl;
callback(topic,payload,len-llen-3-tl);
}
}
} else if (type == MQTTPINGREQ) {
buffer[0] = MQTTPINGRESP;
buffer[1] = 0;
_client->write(buffer,2);
} else if (type == MQTTPINGRESP) {
pingOutstanding = false;
}
} else if (!connected()) {
// readPacket has closed the connection
return false;
}
}
return true;
}
return false;
}
The type value is 208 which is MQTTPINGRESP not 48 which is MQTTPUBLISH.
So, where is the problem?
Is my library or my code?
I download library from https://www.arduino.cc/reference/en/libraries/pubsubclient/