experimental mqtt client supporting large packets

lib/async-mqtt-client/src/AsyncMqttClient.h

@@ -3,4 +3,4 @@
 
 #include "AsyncMqttClient.hpp"
 
-#endif // SRC_ASYNCMQTTCLIENT_H_
+#endif  // SRC_ASYNCMQTTCLIENT_H_

lib/async-mqtt-client/src/AsyncMqttClient.hpp

@@ -5,6 +5,10 @@
 
 #include "Arduino.h"
 
+#ifndef MQTT_MIN_FREE_MEMORY
+#define MQTT_MIN_FREE_MEMORY 4096
+#endif
+
 #ifdef ESP32
 #include <AsyncTCP.h>
 #include <freertos/semphr.h>
@@ -38,137 +42,137 @@
 #include "AsyncMqttClient/Packets/PubRecPacket.hpp"
 #include "AsyncMqttClient/Packets/PubCompPacket.hpp"
 
-#if ESP32
-#define SEMAPHORE_TAKE(X)                                                                                                                                      \
-    if (xSemaphoreTake(_xSemaphore, 1000 / portTICK_PERIOD_MS) != pdTRUE) {                                                                                    \
-        return X;                                                                                                                                              \
-    } // Waits max 1000ms
-#define SEMAPHORE_GIVE() xSemaphoreGive(_xSemaphore);
-#elif defined(ESP8266)
-#define SEMAPHORE_TAKE(X) void()
-#define SEMAPHORE_GIVE() void()
-#endif
+#include "AsyncMqttClient/Packets/Out/Connect.hpp"
+#include "AsyncMqttClient/Packets/Out/PingReq.hpp"
+#include "AsyncMqttClient/Packets/Out/PubAck.hpp"
+#include "AsyncMqttClient/Packets/Out/Disconn.hpp"
+#include "AsyncMqttClient/Packets/Out/Subscribe.hpp"
+#include "AsyncMqttClient/Packets/Out/Unsubscribe.hpp"
+#include "AsyncMqttClient/Packets/Out/Publish.hpp"
 
 class AsyncMqttClient {
-  public:
-    AsyncMqttClient();
-    ~AsyncMqttClient();
+ public:
+  AsyncMqttClient();
+  ~AsyncMqttClient();
 
-    AsyncMqttClient & setKeepAlive(uint16_t keepAlive);
-    AsyncMqttClient & setClientId(const char * clientId);
-    AsyncMqttClient & setCleanSession(bool cleanSession);
-    AsyncMqttClient & setMaxTopicLength(uint16_t maxTopicLength);
-    AsyncMqttClient & setCredentials(const char * username, const char * password = nullptr);
-    AsyncMqttClient & setWill(const char * topic, uint8_t qos, bool retain, const char * payload = nullptr, size_t length = 0);
-    AsyncMqttClient & setServer(IPAddress ip, uint16_t port);
-    AsyncMqttClient & setServer(const char * host, uint16_t port);
+  AsyncMqttClient& setKeepAlive(uint16_t keepAlive);
+  AsyncMqttClient& setClientId(const char* clientId);
+  AsyncMqttClient& setCleanSession(bool cleanSession);
+  AsyncMqttClient& setMaxTopicLength(uint16_t maxTopicLength);
+  AsyncMqttClient& setCredentials(const char* username, const char* password = nullptr);
+  AsyncMqttClient& setWill(const char* topic, uint8_t qos, bool retain, const char* payload = nullptr, size_t length = 0);
+  AsyncMqttClient& setServer(IPAddress ip, uint16_t port);
+  AsyncMqttClient& setServer(const char* host, uint16_t port);
 #if ASYNC_TCP_SSL_ENABLED
-    AsyncMqttClient & setSecure(bool secure);
-    AsyncMqttClient & addServerFingerprint(const uint8_t * fingerprint);
+  AsyncMqttClient& setSecure(bool secure);
+  AsyncMqttClient& addServerFingerprint(const uint8_t* fingerprint);
 #endif
 
-    AsyncMqttClient & onConnect(AsyncMqttClientInternals::OnConnectUserCallback callback);
-    AsyncMqttClient & onDisconnect(AsyncMqttClientInternals::OnDisconnectUserCallback callback);
-    AsyncMqttClient & onSubscribe(AsyncMqttClientInternals::OnSubscribeUserCallback callback);
-    AsyncMqttClient & onUnsubscribe(AsyncMqttClientInternals::OnUnsubscribeUserCallback callback);
-    AsyncMqttClient & onMessage(AsyncMqttClientInternals::OnMessageUserCallback callback, const char * _userTopic = "#");
-    AsyncMqttClient & onFilteredMessage(AsyncMqttClientInternals::OnMessageUserCallback callback, const char * _userTopic);
-    AsyncMqttClient & onPublish(AsyncMqttClientInternals::OnPublishUserCallback callback);
+  AsyncMqttClient& onConnect(AsyncMqttClientInternals::OnConnectUserCallback callback);
+  AsyncMqttClient& onDisconnect(AsyncMqttClientInternals::OnDisconnectUserCallback callback);
+  AsyncMqttClient& onSubscribe(AsyncMqttClientInternals::OnSubscribeUserCallback callback);
+  AsyncMqttClient& onUnsubscribe(AsyncMqttClientInternals::OnUnsubscribeUserCallback callback);
+  AsyncMqttClient& onMessage(AsyncMqttClientInternals::OnMessageUserCallback callback);
+  AsyncMqttClient& onPublish(AsyncMqttClientInternals::OnPublishUserCallback callback);
 
-    bool     connected() const;
-    void     connect();
-    void     disconnect(bool force = false);
-    uint16_t subscribe(const char * topic, uint8_t qos);
-    uint16_t subscribe(const char * topic, uint8_t qos, AsyncMqttClientInternals::OnMessageUserCallback callback);
-    uint16_t unsubscribe(const char * topic);
-    uint16_t publish(const char * topic, uint8_t qos, bool retain, const char * payload = nullptr, size_t length = 0, bool dup = false, uint16_t message_id = 0);
+  bool connected() const;
+  void connect();
+  void disconnect(bool force = false);
+  uint16_t subscribe(const char* topic, uint8_t qos);
+  uint16_t unsubscribe(const char* topic);
+  uint16_t publish(const char* topic, uint8_t qos, bool retain, const char* payload = nullptr, size_t length = 0, bool dup = false, uint16_t message_id = 0);
 
-    const char * getClientId();
+  const char* getClientId() const;
 
-  private:
-    AsyncClient _client;
+ private:
+  AsyncClient _client;
+  AsyncMqttClientInternals::OutPacket* _head;
+  AsyncMqttClientInternals::OutPacket* _tail;
+  size_t _sent;
+  enum {
+    CONNECTING,
+    CONNECTED,
+    DISCONNECTING,
+    DISCONNECTED
+  } _state;
+  bool _tlsBadFingerprint;
+  uint32_t _lastClientActivity;
+  uint32_t _lastServerActivity;
+  uint32_t _lastPingRequestTime;
 
-    bool     _connected;
-    bool     _lockMutiConnections;
-    bool     _connectPacketNotEnoughSpace;
-    bool     _disconnectFlagged;
-    bool     _tlsBadFingerprint;
-    uint32_t _lastClientActivity;
-    uint32_t _lastServerActivity;
-    uint32_t _lastPingRequestTime;
-
-    char         _generatedClientId[18 + 1]; // esp8266-abc123 and esp32-abcdef123456
-    IPAddress    _ip;
-    const char * _host;
-    bool         _useIp;
+  char _generatedClientId[18 + 1];  // esp8266-abc123 and esp32-abcdef123456
+  IPAddress _ip;
+  const char* _host;
+  bool _useIp;
 #if ASYNC_TCP_SSL_ENABLED
-    bool _secure;
+  bool _secure;
 #endif
-    uint16_t     _port;
-    uint16_t     _keepAlive;
-    bool         _cleanSession;
-    const char * _clientId;
-    const char * _username;
-    const char * _password;
-    const char * _willTopic;
-    const char * _willPayload;
-    uint16_t     _willPayloadLength;
-    uint8_t      _willQos;
-    bool         _willRetain;
+  uint16_t _port;
+  uint16_t _keepAlive;
+  bool _cleanSession;
+  const char* _clientId;
+  const char* _username;
+  const char* _password;
+  const char* _willTopic;
+  const char* _willPayload;
+  uint16_t _willPayloadLength;
+  uint8_t _willQos;
+  bool _willRetain;
 
 #if ASYNC_TCP_SSL_ENABLED
-    std::vector<std::array<uint8_t, SHA1_SIZE>> _secureServerFingerprints;
+  std::vector<std::array<uint8_t, SHA1_SIZE>> _secureServerFingerprints;
 #endif
 
-    std::vector<AsyncMqttClientInternals::OnConnectUserCallback>         _onConnectUserCallbacks;
-    std::vector<AsyncMqttClientInternals::OnDisconnectUserCallback>      _onDisconnectUserCallbacks;
-    std::vector<AsyncMqttClientInternals::OnSubscribeUserCallback>       _onSubscribeUserCallbacks;
-    std::vector<AsyncMqttClientInternals::OnUnsubscribeUserCallback>     _onUnsubscribeUserCallbacks;
-    std::vector<AsyncMqttClientInternals::onFilteredMessageUserCallback> _onMessageUserCallbacks;
-    std::vector<AsyncMqttClientInternals::OnPublishUserCallback>         _onPublishUserCallbacks;
+  std::vector<AsyncMqttClientInternals::OnConnectUserCallback> _onConnectUserCallbacks;
+  std::vector<AsyncMqttClientInternals::OnDisconnectUserCallback> _onDisconnectUserCallbacks;
+  std::vector<AsyncMqttClientInternals::OnSubscribeUserCallback> _onSubscribeUserCallbacks;
+  std::vector<AsyncMqttClientInternals::OnUnsubscribeUserCallback> _onUnsubscribeUserCallbacks;
+  std::vector<AsyncMqttClientInternals::OnMessageUserCallback> _onMessageUserCallbacks;
+  std::vector<AsyncMqttClientInternals::OnPublishUserCallback> _onPublishUserCallbacks;
 
-    AsyncMqttClientInternals::ParsingInformation _parsingInformation;
-    AsyncMqttClientInternals::Packet *           _currentParsedPacket;
-    uint8_t                                      _remainingLengthBufferPosition;
-    char                                         _remainingLengthBuffer[4];
+  AsyncMqttClientInternals::ParsingInformation _parsingInformation;
+  AsyncMqttClientInternals::Packet* _currentParsedPacket;
+  uint8_t _remainingLengthBufferPosition;
+  char _remainingLengthBuffer[4];
 
-    uint16_t _nextPacketId;
+  std::vector<AsyncMqttClientInternals::PendingPubRel> _pendingPubRels;
 
-    std::vector<AsyncMqttClientInternals::PendingPubRel> _pendingPubRels;
-
-    std::vector<AsyncMqttClientInternals::PendingAck> _toSendAcks;
-
-#ifdef ESP32
-    SemaphoreHandle_t _xSemaphore = nullptr;
+#if defined(ESP32)
+  SemaphoreHandle_t _xSemaphore = nullptr;
+#elif defined(ESP8266)
+  bool _xSemaphore = false;
 #endif
 
-    void _clear();
-    void _freeCurrentParsedPacket();
+  void _clear();
+  void _freeCurrentParsedPacket();
 
-    // TCP
-    void        _onConnect(AsyncClient * client);
-    void        _onDisconnect(AsyncClient * client);
-    static void _onError(AsyncClient * client, int8_t error);
-    void        _onTimeout(AsyncClient * client, uint32_t time);
-    static void _onAck(AsyncClient * client, size_t len, uint32_t time);
-    void        _onData(AsyncClient * client, char * data, size_t len);
-    void        _onPoll(AsyncClient * client);
+  // TCP
+  void _onConnect();
+  void _onDisconnect();
+  // void _onError(int8_t error);
+  // void _onTimeout();
+  void _onAck(size_t len);
+  void _onData(char* data, size_t len);
+  void _onPoll();
 
-    // MQTT
-    void _onPingResp();
-    void _onConnAck(bool sessionPresent, uint8_t connectReturnCode);
-    void _onSubAck(uint16_t packetId, char status);
-    void _onUnsubAck(uint16_t packetId);
-    void _onMessage(char * topic, char * payload, uint8_t qos, bool dup, bool retain, size_t len, size_t index, size_t total, uint16_t packetId);
-    void _onPublish(uint16_t packetId, uint8_t qos);
-    void _onPubRel(uint16_t packetId);
-    void _onPubAck(uint16_t packetId);
-    void _onPubRec(uint16_t packetId);
-    void _onPubComp(uint16_t packetId);
+  // QUEUE
+  void _insert(AsyncMqttClientInternals::OutPacket* packet);    // for PUBREL
+  void _addFront(AsyncMqttClientInternals::OutPacket* packet);  // for CONNECT
+  void _addBack(AsyncMqttClientInternals::OutPacket* packet);   // all the rest
+  void _handleQueue();
+  void _clearQueue(bool keepSessionData);
 
-    bool _sendPing();
-    void _sendAcks();
-    bool _sendDisconnect();
+  // MQTT
+  void _onPingResp();
+  void _onConnAck(bool sessionPresent, uint8_t connectReturnCode);
+  void _onSubAck(uint16_t packetId, char status);
+  void _onUnsubAck(uint16_t packetId);
+  void _onMessage(char* topic, char* payload, uint8_t qos, bool dup, bool retain, size_t len, size_t index, size_t total, uint16_t packetId);
+  void _onPublish(uint16_t packetId, uint8_t qos);
+  void _onPubRel(uint16_t packetId);
+  void _onPubAck(uint16_t packetId);
+  void _onPubRec(uint16_t packetId);
+  void _onPubComp(uint16_t packetId);
 
-    uint16_t _getNextPacketId();
+  void _sendPing();
 };

lib/async-mqtt-client/src/AsyncMqttClient/Callbacks.hpp

@@ -4,6 +4,7 @@
 
 #include "DisconnectReasons.hpp"
 #include "MessageProperties.hpp"
+#include "Errors.hpp"
 
 namespace AsyncMqttClientInternals {
 // user callbacks
@@ -12,9 +13,8 @@ typedef std::function<void(AsyncMqttClientDisconnectReason reason)> OnDisconnect
 typedef std::function<void(uint16_t packetId, uint8_t qos)> OnSubscribeUserCallback;
 typedef std::function<void(uint16_t packetId)> OnUnsubscribeUserCallback;
 typedef std::function<void(char* topic, char* payload, AsyncMqttClientMessageProperties properties, size_t len, size_t index, size_t total)> OnMessageUserCallback;
-// typedef std::pair<std::string, std::function<void(char* topic, char* payload, AsyncMqttClientMessageProperties properties, size_t len, size_t index, size_t total)>> onFilteredMessageUserCallback;
-typedef std::pair<char*, std::function<void(char* topic, char* payload, AsyncMqttClientMessageProperties properties, size_t len, size_t index, size_t total)>> onFilteredMessageUserCallback;
 typedef std::function<void(uint16_t packetId)> OnPublishUserCallback;
+typedef std::function<void(uint16_t packetId, AsyncMqttClientError error)> OnErrorUserCallback;
 
 // internal callbacks
 typedef std::function<void(bool sessionPresent, uint8_t connectReturnCode)> OnConnAckInternalCallback;

lib/async-mqtt-client/src/AsyncMqttClient/Errors.hpp

@@ -0,0 +1,6 @@
+#pragma once
+
+enum class AsyncMqttClientError : uint8_t {
+  MAX_RETRIES = 0,
+  OUT_OF_MEMORY = 1
+};

lib/async-mqtt-client/src/AsyncMqttClient/Helpers.hpp

@@ -35,4 +35,27 @@ class Helpers {
     return bytesNeeded;
   }
 };
+
+#if defined(ARDUINO_ARCH_ESP32)
+  #define SEMAPHORE_TAKE() xSemaphoreTake(_xSemaphore, portMAX_DELAY)
+  #define SEMAPHORE_GIVE() xSemaphoreGive(_xSemaphore)
+  #define GET_FREE_MEMORY() ESP.getMaxAllocHeap()
+  #include <esp32-hal-log.h>
+#elif defined(ARDUINO_ARCH_ESP8266)
+  #define SEMAPHORE_TAKE(X) while (_xSemaphore) { /*ESP.wdtFeed();*/ } _xSemaphore = true
+  #define SEMAPHORE_GIVE() _xSemaphore = false
+  #define GET_FREE_MEMORY() ESP.getMaxFreeBlockSize()
+  #if defined(DEBUG_ESP_PORT) && defined(DEBUG_ASYNC_MQTT_CLIENT)
+    #define log_i(...) DEBUG_ESP_PORT.printf(__VA_ARGS__); DEBUG_ESP_PORT.print("\n")
+    #define log_e(...) DEBUG_ESP_PORT.printf(__VA_ARGS__); DEBUG_ESP_PORT.print("\n")
+    #define log_w(...) DEBUG_ESP_PORT.printf(__VA_ARGS__); DEBUG_ESP_PORT.print("\n")
+  #else
+    #define log_i(...)
+    #define log_e(...)
+    #define log_w(...)
+  #endif
+#else
+  #pragma error "No valid architecture"
+#endif
+
 }  // namespace AsyncMqttClientInternals

lib/async-mqtt-client/src/AsyncMqttClient/Packets/Out/Connect.cpp

@@ -0,0 +1,162 @@
+#include "Connect.hpp"
+
+using AsyncMqttClientInternals::ConnectOutPacket;
+
+ConnectOutPacket::ConnectOutPacket(bool cleanSession,
+                                   const char* username,
+                                   const char* password,
+                                   const char* willTopic,
+                                   bool willRetain,
+                                   uint8_t willQos,
+                                   const char* willPayload,
+                                   uint16_t willPayloadLength,
+                                   uint16_t keepAlive,
+                                   const char* clientId) {
+  char fixedHeader[5];
+  fixedHeader[0] = AsyncMqttClientInternals::PacketType.CONNECT;
+  fixedHeader[0] = fixedHeader[0] << 4;
+  fixedHeader[0] = fixedHeader[0] | AsyncMqttClientInternals::HeaderFlag.CONNECT_RESERVED;
+
+  uint16_t protocolNameLength = 4;
+  char protocolNameLengthBytes[2];
+  protocolNameLengthBytes[0] = protocolNameLength >> 8;
+  protocolNameLengthBytes[1] = protocolNameLength & 0xFF;
+
+  char protocolLevel[1];
+  protocolLevel[0] = 0x04;
+
+  char connectFlags[1];
+  connectFlags[0] = 0;
+  if (cleanSession) connectFlags[0] |= AsyncMqttClientInternals::ConnectFlag.CLEAN_SESSION;
+  if (username != nullptr) connectFlags[0] |= AsyncMqttClientInternals::ConnectFlag.USERNAME;
+  if (password != nullptr) connectFlags[0] |= AsyncMqttClientInternals::ConnectFlag.PASSWORD;
+  if (willTopic != nullptr) {
+    connectFlags[0] |= AsyncMqttClientInternals::ConnectFlag.WILL;
+    if (willRetain) connectFlags[0] |= AsyncMqttClientInternals::ConnectFlag.WILL_RETAIN;
+    switch (willQos) {
+      case 0:
+        connectFlags[0] |= AsyncMqttClientInternals::ConnectFlag.WILL_QOS0;
+        break;
+      case 1:
+        connectFlags[0] |= AsyncMqttClientInternals::ConnectFlag.WILL_QOS1;
+        break;
+      case 2:
+        connectFlags[0] |= AsyncMqttClientInternals::ConnectFlag.WILL_QOS2;
+        break;
+    }
+  }
+
+  char keepAliveBytes[2];
+  keepAliveBytes[0] = keepAlive >> 8;
+  keepAliveBytes[1] = keepAlive & 0xFF;
+
+  uint16_t clientIdLength = strlen(clientId);
+  char clientIdLengthBytes[2];
+  clientIdLengthBytes[0] = clientIdLength >> 8;
+  clientIdLengthBytes[1] = clientIdLength & 0xFF;
+
+  // Optional fields
+  uint16_t willTopicLength = 0;
+  char willTopicLengthBytes[2];
+  char willPayloadLengthBytes[2];
+  if (willTopic != nullptr) {
+    willTopicLength = strlen(willTopic);
+    willTopicLengthBytes[0] = willTopicLength >> 8;
+    willTopicLengthBytes[1] = willTopicLength & 0xFF;
+
+    if (willPayload != nullptr && willPayloadLength == 0) willPayloadLength = strlen(willPayload);
+
+    willPayloadLengthBytes[0] = willPayloadLength >> 8;
+    willPayloadLengthBytes[1] = willPayloadLength & 0xFF;
+  }
+
+  uint16_t usernameLength = 0;
+  char usernameLengthBytes[2];
+  if (username != nullptr) {
+    usernameLength = strlen(username);
+    usernameLengthBytes[0] = usernameLength >> 8;
+    usernameLengthBytes[1] = usernameLength & 0xFF;
+  }
+
+  uint16_t passwordLength = 0;
+  char passwordLengthBytes[2];
+  if (password != nullptr) {
+    passwordLength = strlen(password);
+    passwordLengthBytes[0] = passwordLength >> 8;
+    passwordLengthBytes[1] = passwordLength & 0xFF;
+  }
+
+  uint32_t remainingLength = 2 + protocolNameLength + 1 + 1 + 2 + 2 + clientIdLength;  // always present
+  if (willTopic != nullptr) remainingLength += 2 + willTopicLength + 2 + willPayloadLength;
+  if (username != nullptr) remainingLength += 2 + usernameLength;
+  if (password != nullptr) remainingLength += 2 + passwordLength;
+  uint8_t remainingLengthLength = AsyncMqttClientInternals::Helpers::encodeRemainingLength(remainingLength, fixedHeader + 1);
+
+  uint32_t neededSpace = 1 + remainingLengthLength;
+  neededSpace += 2;
+  neededSpace += protocolNameLength;
+  neededSpace += 1;
+  neededSpace += 1;
+  neededSpace += 2;
+  neededSpace += 2;
+  neededSpace += clientIdLength;
+  if (willTopic != nullptr) {
+    neededSpace += 2;
+    neededSpace += willTopicLength;
+
+    neededSpace += 2;
+    if (willPayload != nullptr) neededSpace += willPayloadLength;
+  }
+  if (username != nullptr) {
+    neededSpace += 2;
+    neededSpace += usernameLength;
+  }
+  if (password != nullptr) {
+    neededSpace += 2;
+    neededSpace += passwordLength;
+  }
+
+  _data.reserve(neededSpace);
+
+  _data.insert(_data.end(), fixedHeader, fixedHeader + 1 + remainingLengthLength);
+
+  _data.push_back(protocolNameLengthBytes[0]);
+  _data.push_back(protocolNameLengthBytes[1]);
+
+  _data.push_back('M');
+  _data.push_back('Q');
+  _data.push_back('T');
+  _data.push_back('T');
+
+  _data.push_back(protocolLevel[0]);
+  _data.push_back(connectFlags[0]);
+  _data.push_back(keepAliveBytes[0]);
+  _data.push_back(keepAliveBytes[1]);
+  _data.push_back(clientIdLengthBytes[0]);
+  _data.push_back(clientIdLengthBytes[1]);
+
+  _data.insert(_data.end(), clientId, clientId + clientIdLength);
+  if (willTopic != nullptr) {
+    _data.insert(_data.end(), willTopicLengthBytes, willTopicLengthBytes + 2);
+    _data.insert(_data.end(), willTopic, willTopic + willTopicLength);
+
+    _data.insert(_data.end(), willPayloadLengthBytes, willPayloadLengthBytes + 2);
+    if (willPayload != nullptr) _data.insert(_data.end(), willPayload, willPayload + willPayloadLength);
+  }
+  if (username != nullptr) {
+    _data.insert(_data.end(), usernameLengthBytes, usernameLengthBytes + 2);
+    _data.insert(_data.end(), username, username + usernameLength);
+  }
+  if (password != nullptr) {
+    _data.insert(_data.end(), passwordLengthBytes, passwordLengthBytes + 2);
+    _data.insert(_data.end(), password, password + passwordLength);
+  }
+}
+
+const uint8_t* ConnectOutPacket::data(size_t index) const {
+  return &_data.data()[index];
+}
+
+size_t ConnectOutPacket::size() const {
+  return _data.size();
+}

lib/async-mqtt-client/src/AsyncMqttClient/Packets/Out/Connect.hpp

@@ -0,0 +1,29 @@
+#pragma once
+
+#include <vector>
+#include <cstring>  // strlen
+
+#include "OutPacket.hpp"
+#include "../../Flags.hpp"
+#include "../../Helpers.hpp"
+
+namespace AsyncMqttClientInternals {
+class ConnectOutPacket : public OutPacket {
+ public:
+  ConnectOutPacket(bool cleanSession,
+                   const char* username,
+                   const char* password,
+                   const char* willTopic,
+                   bool willRetain,
+                   uint8_t willQos,
+                   const char* willPayload,
+                   uint16_t willPayloadLength,
+                   uint16_t keepAlive,
+                   const char* clientId);
+  const uint8_t* data(size_t index = 0) const;
+  size_t size() const;
+
+ private:
+  std::vector<uint8_t> _data;
+};
+}  // namespace AsyncMqttClientInternals

lib/async-mqtt-client/src/AsyncMqttClient/Packets/Out/Disconn.cpp

@@ -0,0 +1,18 @@
+#include "Disconn.hpp"
+
+using AsyncMqttClientInternals::DisconnOutPacket;
+
+DisconnOutPacket::DisconnOutPacket() {
+  _data[0] = AsyncMqttClientInternals::PacketType.DISCONNECT;
+  _data[0] = _data[0] << 4;
+  _data[0] = _data[0] | AsyncMqttClientInternals::HeaderFlag.DISCONNECT_RESERVED;
+  _data[1] = 0;
+}
+
+const uint8_t* DisconnOutPacket::data(size_t index) const {
+  return &_data[index];
+}
+
+size_t DisconnOutPacket::size() const {
+  return 2;
+}

lib/async-mqtt-client/src/AsyncMqttClient/Packets/Out/Disconn.hpp

@@ -0,0 +1,17 @@
+#pragma once
+
+#include "OutPacket.hpp"
+#include "../../Flags.hpp"
+#include "../../Helpers.hpp"
+
+namespace AsyncMqttClientInternals {
+class DisconnOutPacket : public OutPacket {
+ public:
+  DisconnOutPacket();
+  const uint8_t* data(size_t index = 0) const;
+  size_t size() const;
+
+ private:
+  uint8_t _data[2];
+};
+}  // namespace AsyncMqttClientInternals

lib/async-mqtt-client/src/AsyncMqttClient/Packets/Out/OutPacket.cpp

@@ -0,0 +1,44 @@
+#include "OutPacket.hpp"
+
+using AsyncMqttClientInternals::OutPacket;
+
+OutPacket::OutPacket()
+: next(nullptr)
+, timeout(0)
+, noTries(0)
+, _released(true)
+, _packetId(0) {}
+
+OutPacket::~OutPacket() {}
+
+bool OutPacket::released() const {
+  return _released;
+}
+
+uint8_t OutPacket::packetType() const {
+  return data(0)[0] >> 4;
+}
+
+uint16_t OutPacket::packetId() const {
+  return _packetId;
+}
+
+uint8_t OutPacket::qos() const {
+  if (packetType() == AsyncMqttClientInternals::PacketType.PUBLISH) {
+    return (data()[1] & 0x06) >> 1;
+  }
+  return 0;
+}
+
+void OutPacket::release() {
+  _released = true;
+}
+
+uint16_t OutPacket::_nextPacketId = 0;
+
+uint16_t OutPacket::_getNextPacketId() {
+  if (++_nextPacketId == 0) {
+    ++_nextPacketId;
+  }
+  return _nextPacketId;
+}

lib/async-mqtt-client/src/AsyncMqttClient/Packets/Out/OutPacket.hpp

@@ -0,0 +1,35 @@
+#pragma once
+
+#include <stdint.h>  // uint*_t
+#include <stddef.h>  // size_t
+#include <algorithm>  // std::min
+
+#include "../../Flags.hpp"
+
+namespace AsyncMqttClientInternals {
+class OutPacket {
+ public:
+  OutPacket();
+  virtual ~OutPacket();
+  virtual const uint8_t* data(size_t index = 0) const = 0;
+  virtual size_t size() const = 0;
+  bool released() const;
+  uint8_t packetType() const;
+  uint16_t packetId() const;
+  uint8_t qos() const;
+  void release();
+
+ public:
+  OutPacket* next;
+  uint32_t timeout;
+  uint8_t noTries;
+
+ protected:
+  static uint16_t _getNextPacketId();
+  bool _released;
+  uint16_t _packetId;
+
+ private:
+  static uint16_t _nextPacketId;
+};
+}  // namespace AsyncMqttClientInternals

lib/async-mqtt-client/src/AsyncMqttClient/Packets/Out/PingReq.cpp

@@ -0,0 +1,18 @@
+#include "PingReq.hpp"
+
+using AsyncMqttClientInternals::PingReqOutPacket;
+
+PingReqOutPacket::PingReqOutPacket() {
+  _data[0] = AsyncMqttClientInternals::PacketType.PINGREQ;
+  _data[0] = _data[0] << 4;
+  _data[0] = _data[0] | AsyncMqttClientInternals::HeaderFlag.PINGREQ_RESERVED;
+  _data[1] = 0;
+}
+
+const uint8_t* PingReqOutPacket::data(size_t index) const {
+  return &_data[index];;
+}
+
+size_t PingReqOutPacket::size() const {
+  return 2;
+}

lib/async-mqtt-client/src/AsyncMqttClient/Packets/Out/PingReq.hpp

@@ -0,0 +1,17 @@
+#pragma once
+
+#include "OutPacket.hpp"
+#include "../../Flags.hpp"
+#include "../../Helpers.hpp"
+
+namespace AsyncMqttClientInternals {
+class PingReqOutPacket : public OutPacket {
+ public:
+  PingReqOutPacket();
+  const uint8_t* data(size_t index = 0) const;
+  size_t size() const;
+
+ private:
+  uint8_t _data[2];
+};
+}  // namespace AsyncMqttClientInternals

lib/async-mqtt-client/src/AsyncMqttClient/Packets/Out/PubAck.cpp

@@ -0,0 +1,26 @@
+#include "PubAck.hpp"
+
+using AsyncMqttClientInternals::PubAckOutPacket;
+
+PubAckOutPacket::PubAckOutPacket(PendingAck pendingAck) {
+  _data[0] = pendingAck.packetType;
+  _data[0] = _data[0] << 4;
+  _data[0] = _data[0] | pendingAck.headerFlag;
+  _data[1] = 2;
+  _packetId = pendingAck.packetId;
+  _data[2] = pendingAck.packetId >> 8;
+  _data[3] = pendingAck.packetId & 0xFF;
+  _released = false;
+  if (packetType() == AsyncMqttClientInternals::PacketType.PUBREL ||
+      packetType() == AsyncMqttClientInternals::PacketType.PUBREC) {
+    _released = false;
+  }
+}
+
+const uint8_t* PubAckOutPacket::data(size_t index) const {
+  return &_data[index];
+}
+
+size_t PubAckOutPacket::size() const {
+  return 4;
+}

lib/async-mqtt-client/src/AsyncMqttClient/Packets/Out/PubAck.hpp

@@ -0,0 +1,18 @@
+#pragma once
+
+#include "OutPacket.hpp"
+#include "../../Flags.hpp"
+#include "../../Helpers.hpp"
+#include "../../Storage.hpp"
+
+namespace AsyncMqttClientInternals {
+class PubAckOutPacket : public OutPacket {
+ public:
+  explicit PubAckOutPacket(PendingAck pendingAck);
+  const uint8_t* data(size_t index = 0) const;
+  size_t size() const;
+
+ private:
+  uint8_t _data[4];
+};
+}  // namespace AsyncMqttClientInternals

lib/async-mqtt-client/src/AsyncMqttClient/Packets/Out/Publish.cpp

@@ -0,0 +1,69 @@
+#include "Publish.hpp"
+
+using AsyncMqttClientInternals::PublishOutPacket;
+
+PublishOutPacket::PublishOutPacket(const char* topic, uint8_t qos, bool retain, const char* payload, size_t length) {
+  char fixedHeader[5];
+  fixedHeader[0] = AsyncMqttClientInternals::PacketType.PUBLISH;
+  fixedHeader[0] = fixedHeader[0] << 4;
+  // if (dup) fixedHeader[0] |= AsyncMqttClientInternals::HeaderFlag.PUBLISH_DUP;
+  if (retain) fixedHeader[0] |= AsyncMqttClientInternals::HeaderFlag.PUBLISH_RETAIN;
+  switch (qos) {
+    case 0:
+      fixedHeader[0] |= AsyncMqttClientInternals::HeaderFlag.PUBLISH_QOS0;
+      break;
+    case 1:
+      fixedHeader[0] |= AsyncMqttClientInternals::HeaderFlag.PUBLISH_QOS1;
+      break;
+    case 2:
+      fixedHeader[0] |= AsyncMqttClientInternals::HeaderFlag.PUBLISH_QOS2;
+      break;
+  }
+
+  uint16_t topicLength = strlen(topic);
+  char topicLengthBytes[2];
+  topicLengthBytes[0] = topicLength >> 8;
+  topicLengthBytes[1] = topicLength & 0xFF;
+
+  uint32_t payloadLength = length;
+  if (payload != nullptr && payloadLength == 0) payloadLength = strlen(payload);
+
+  uint32_t remainingLength = 2 + topicLength + payloadLength;
+  if (qos != 0) remainingLength += 2;
+  uint8_t remainingLengthLength = AsyncMqttClientInternals::Helpers::encodeRemainingLength(remainingLength, fixedHeader + 1);
+
+  size_t neededSpace = 0;
+  neededSpace += 1 + remainingLengthLength;
+  neededSpace += 2;
+  neededSpace += topicLength;
+  if (qos != 0) neededSpace += 2;
+  if (payload != nullptr) neededSpace += payloadLength;
+
+  _data.reserve(neededSpace);
+
+  _packetId = (qos !=0) ? _getNextPacketId() : 1;
+  char packetIdBytes[2];
+  packetIdBytes[0] = _packetId >> 8;
+  packetIdBytes[1] = _packetId & 0xFF;
+
+  _data.insert(_data.end(), fixedHeader, fixedHeader + 1 + remainingLengthLength);
+  _data.insert(_data.end(), topicLengthBytes, topicLengthBytes + 2);
+  _data.insert(_data.end(), topic, topic + topicLength);
+  if (qos != 0) {
+    _data.insert(_data.end(), packetIdBytes, packetIdBytes + 2);
+    _released = false;
+  }
+  if (payload != nullptr) _data.insert(_data.end(), payload, payload + payloadLength);
+}
+
+const uint8_t* PublishOutPacket::data(size_t index) const {
+  return &_data.data()[index];
+}
+
+size_t PublishOutPacket::size() const {
+  return _data.size();
+}
+
+void PublishOutPacket::setDup() {
+  _data[0] |= AsyncMqttClientInternals::HeaderFlag.PUBLISH_DUP;
+}

lib/async-mqtt-client/src/AsyncMqttClient/Packets/Out/Publish.hpp

@@ -0,0 +1,23 @@
+#pragma once
+
+#include <cstring>  // strlen
+#include <vector>
+
+#include "OutPacket.hpp"
+#include "../../Flags.hpp"
+#include "../../Helpers.hpp"
+#include "../../Storage.hpp"
+
+namespace AsyncMqttClientInternals {
+class PublishOutPacket : public OutPacket {
+ public:
+  PublishOutPacket(const char* topic, uint8_t qos, bool retain, const char* payload, size_t length);
+  const uint8_t* data(size_t index = 0) const;
+  size_t size() const;
+
+  void setDup();  // you cannot unset dup
+
+ private:
+  std::vector<uint8_t> _data;
+};
+}  // namespace AsyncMqttClientInternals

lib/async-mqtt-client/src/AsyncMqttClient/Packets/Out/Subscribe.cpp

@@ -0,0 +1,49 @@
+#include "Subscribe.hpp"
+
+using AsyncMqttClientInternals::SubscribeOutPacket;
+
+SubscribeOutPacket::SubscribeOutPacket(const char* topic, uint8_t qos) {
+  char fixedHeader[5];
+  fixedHeader[0] = AsyncMqttClientInternals::PacketType.SUBSCRIBE;
+  fixedHeader[0] = fixedHeader[0] << 4;
+  fixedHeader[0] = fixedHeader[0] | AsyncMqttClientInternals::HeaderFlag.SUBSCRIBE_RESERVED;
+
+  uint16_t topicLength = strlen(topic);
+  char topicLengthBytes[2];
+  topicLengthBytes[0] = topicLength >> 8;
+  topicLengthBytes[1] = topicLength & 0xFF;
+
+  char qosByte[1];
+  qosByte[0] = qos;
+
+  uint8_t remainingLengthLength = AsyncMqttClientInternals::Helpers::encodeRemainingLength(2 + 2 + topicLength + 1, fixedHeader + 1);
+
+  size_t neededSpace = 0;
+  neededSpace += 1 + remainingLengthLength;
+  neededSpace += 2;
+  neededSpace += 2;
+  neededSpace += topicLength;
+  neededSpace += 1;
+
+  _data.reserve(neededSpace);
+
+  _packetId = _getNextPacketId();
+  char packetIdBytes[2];
+  packetIdBytes[0] = _packetId >> 8;
+  packetIdBytes[1] = _packetId & 0xFF;
+
+  _data.insert(_data.end(), fixedHeader, fixedHeader + 1 + remainingLengthLength);
+  _data.insert(_data.end(), packetIdBytes, packetIdBytes + 2);
+  _data.insert(_data.end(), topicLengthBytes, topicLengthBytes + 2);
+  _data.insert(_data.end(), topic, topic + topicLength);
+  _data.push_back(qosByte[0]);
+  _released = false;
+}
+
+const uint8_t* SubscribeOutPacket::data(size_t index) const {
+  return &_data.data()[index];
+}
+
+size_t SubscribeOutPacket::size() const {
+  return _data.size();
+}

lib/async-mqtt-client/src/AsyncMqttClient/Packets/Out/Subscribe.hpp

@@ -0,0 +1,21 @@
+#pragma once
+
+#include <cstring>  // strlen
+#include <vector>
+
+#include "OutPacket.hpp"
+#include "../../Flags.hpp"
+#include "../../Helpers.hpp"
+#include "../../Storage.hpp"
+
+namespace AsyncMqttClientInternals {
+class SubscribeOutPacket : public OutPacket {
+ public:
+  SubscribeOutPacket(const char* topic, uint8_t qos);
+  const uint8_t* data(size_t index = 0) const;
+  size_t size() const;
+
+ private:
+  std::vector<uint8_t> _data;
+};
+}  // namespace AsyncMqttClientInternals

lib/async-mqtt-client/src/AsyncMqttClient/Packets/Out/Unsubscribe.cpp

@@ -0,0 +1,42 @@
+#include "Unsubscribe.hpp"
+
+using AsyncMqttClientInternals::UnsubscribeOutPacket;
+
+UnsubscribeOutPacket::UnsubscribeOutPacket(const char* topic) {
+  char fixedHeader[5];
+  fixedHeader[0] = AsyncMqttClientInternals::PacketType.UNSUBSCRIBE;
+  fixedHeader[0] = fixedHeader[0] << 4;
+  fixedHeader[0] = fixedHeader[0] | AsyncMqttClientInternals::HeaderFlag.UNSUBSCRIBE_RESERVED;
+
+  uint16_t topicLength = strlen(topic);
+  char topicLengthBytes[2];
+  topicLengthBytes[0] = topicLength >> 8;
+  topicLengthBytes[1] = topicLength & 0xFF;
+
+  uint8_t remainingLengthLength = AsyncMqttClientInternals::Helpers::encodeRemainingLength(2 + 2 + topicLength, fixedHeader + 1);
+
+  size_t neededSpace = 0;
+  neededSpace += 1 + remainingLengthLength;
+  neededSpace += 2;
+  neededSpace += 2;
+  neededSpace += topicLength;
+
+  _packetId = _getNextPacketId();
+  char packetIdBytes[2];
+  packetIdBytes[0] = _packetId >> 8;
+  packetIdBytes[1] = _packetId & 0xFF;
+
+  _data.insert(_data.end(), fixedHeader, fixedHeader + 1 + remainingLengthLength);
+  _data.insert(_data.end(), packetIdBytes, packetIdBytes + 2);
+  _data.insert(_data.end(), topicLengthBytes, topicLengthBytes + 2);
+  _data.insert(_data.end(), topic, topic + topicLength);
+  _released = false;
+}
+
+const uint8_t* UnsubscribeOutPacket::data(size_t index) const {
+  return &_data.data()[index];
+}
+
+size_t UnsubscribeOutPacket::size() const {
+  return _data.size();
+}

lib/async-mqtt-client/src/AsyncMqttClient/Packets/Out/Unsubscribe.hpp

@@ -0,0 +1,21 @@
+#pragma once
+
+#include <cstring>  // strlen
+#include <vector>
+
+#include "OutPacket.hpp"
+#include "../../Flags.hpp"
+#include "../../Helpers.hpp"
+#include "../../Storage.hpp"
+
+namespace AsyncMqttClientInternals {
+class UnsubscribeOutPacket : public OutPacket {
+ public:
+  explicit UnsubscribeOutPacket(const char* topic);
+  const uint8_t* data(size_t index = 0) const;
+  size_t size() const;
+
+ private:
+  std::vector<uint8_t> _data;
+};
+}  // namespace AsyncMqttClientInternals

lib/async-mqtt-client/src/AsyncMqttClient/Packets/PublishPacket.cpp

@@ -16,8 +16,7 @@ PublishPacket::PublishPacket(ParsingInformation* parsingInformation, OnMessageIn
 , _packetIdMsb(0)
 , _packetId(0)
 , _payloadLength(0)
-, _payloadBytesRead(0)
-, _ptempbuff(0) {
+, _payloadBytesRead(0) {
     _dup = _parsingInformation->packetFlags & HeaderFlag.PUBLISH_DUP;
     _retain = _parsingInformation->packetFlags & HeaderFlag.PUBLISH_RETAIN;
     char qosMasked = _parsingInformation->packetFlags & 0x06;
@@ -79,36 +78,14 @@ void PublishPacket::_preparePayloadHandling(uint32_t payloadLength) {
 
 void PublishPacket::parsePayload(char* data, size_t len, size_t* currentBytePosition) {
   size_t remainToRead = len - (*currentBytePosition);
-  if (_payloadBytesRead + remainToRead > _payloadLength)
-    remainToRead = _payloadLength - _payloadBytesRead;
-  if (!_ignore) {
-    if (remainToRead < _payloadLength) {
-      if (!_ptempbuff) {
-        _ptempbuff = new char[_payloadLength + 1];
-        if (_ptempbuff == nullptr) {
-          _ignore = true;
-          return;
-        }
-        memset(_ptempbuff, 0, _payloadLength + 1);
-        memcpy(&_ptempbuff[_payloadBytesRead], &data[(*currentBytePosition)], remainToRead);
-      } else {
-        memcpy(&_ptempbuff[_payloadBytesRead], &data[(*currentBytePosition)], remainToRead);
-        if ((_payloadBytesRead + remainToRead) == _payloadLength) {
-          _dataCallback(_parsingInformation->topicBuffer, _ptempbuff, _qos, _dup, _retain, _payloadLength, 0, _payloadLength, _packetId);
-          delete[] _ptempbuff;
-          _ptempbuff = NULL;
-        }
-      }
-    } else {
-      _dataCallback(_parsingInformation->topicBuffer, &data[(*currentBytePosition)], _qos, _dup, _retain, remainToRead, _payloadBytesRead, _payloadLength, _packetId);
-    }
-  }
+  if (_payloadBytesRead + remainToRead > _payloadLength) remainToRead = _payloadLength - _payloadBytesRead;
+
+  if (!_ignore) _dataCallback(_parsingInformation->topicBuffer, data + (*currentBytePosition), _qos, _dup, _retain, remainToRead, _payloadBytesRead, _payloadLength, _packetId);
   _payloadBytesRead += remainToRead;
   (*currentBytePosition) += remainToRead;
 
   if (_payloadBytesRead == _payloadLength) {
     _parsingInformation->bufferState = BufferState::NONE;
-    if (!_ignore)
-      _completeCallback(_packetId, _qos);
+    if (!_ignore) _completeCallback(_packetId, _qos);
   }
 }

lib/async-mqtt-client/src/AsyncMqttClient/Packets/PublishPacket.hpp

@@ -34,6 +34,5 @@ class PublishPacket : public Packet {
   uint16_t _packetId;
   uint32_t _payloadLength;
   uint32_t _payloadBytesRead;
-  char*    _ptempbuff;
 };
 }  // namespace AsyncMqttClientInternals