Adds a feature for BLEDescriptors so that they optionally reset their value on client disconnect

libraries/BLE/src/BLE2902.cpp

@@ -17,6 +17,7 @@
 BLE2902::BLE2902() : BLEDescriptor(BLEUUID((uint16_t) 0x2902)) {
 	uint8_t data[2] = { 0, 0 };
 	setValue(data, 2);
+	setResetsOnDisconnect(true);
 } // BLE2902
 
 

libraries/BLE/src/BLEDescriptor.cpp

@@ -30,12 +30,13 @@ BLEDescriptor::BLEDescriptor(const char* uuid, uint16_t len) : BLEDescriptor(BLE
  * @brief BLEDescriptor constructor.
  */
 BLEDescriptor::BLEDescriptor(BLEUUID uuid, uint16_t max_len) {
-	m_bleUUID            = uuid;
-	m_value.attr_len     = 0;                                         // Initial length is 0.
-	m_value.attr_max_len = max_len;                     // Maximum length of the data.
-	m_handle             = NULL_HANDLE;                               // Handle is initially unknown.
-	m_pCharacteristic    = nullptr;                                   // No initial characteristic.
-	m_pCallback          = nullptr;                                   // No initial callback.
+	m_resetValuesOnDisconnect = false;
+	m_bleUUID            	  = uuid;
+	m_value.attr_len          = 0;                 // Initial length is 0.
+	m_value.attr_max_len      = max_len;          // Maximum length of the data.
+	m_handle                  = NULL_HANDLE;     // Handle is initially unknown.
+	m_pCharacteristic         = nullptr;        // No initial characteristic.
+	m_pCallback               = nullptr;       // No initial callback.
 
 	m_value.attr_value   = (uint8_t*) malloc(max_len);  // Allocate storage for the value.
 } // BLEDescriptor
@@ -117,6 +118,13 @@ uint8_t* BLEDescriptor::getValue() {
 	return m_value.attr_value;
 } // getValue
 
+/**
+ * @brief Gets the value of the resetOnDisconnect flag
+ * @return flag
+ */
+bool BLEDescriptor::resetsOnDisconnect(){
+	return m_resetValuesOnDisconnect;
+}
 
 /**
  * @brief Handle GATT server events for the descripttor.
@@ -193,6 +201,14 @@ void BLEDescriptor::handleGATTServerEvent(
 			break;
 		} // ESP_GATTS_READ_EVT
 
+		// Resets the values to its default
+		case ESP_GATTS_DISCONNECT_EVT: {
+			if(this->m_resetValuesOnDisconnect){
+				this->resetValue();
+			}
+			break;
+		}
+
 		default:
 			break;
 	} // switch event
@@ -246,6 +262,22 @@ void BLEDescriptor::setValue(std::string value) {
 	setValue((uint8_t*) value.data(), value.length());
 } // setValue
 
+/**
+ * @brief Sets the reset on discconect flag
+ * @param [in] flag The value of the flag
+ */
+void BLEDescriptor::setResetsOnDisconnect(bool flag){
+	m_resetValuesOnDisconnect = flag;
+}
+
+/**
+ * @brief Resets the value to its default content
+ */
+void BLEDescriptor::resetValue(){
+	memset(m_value.attr_value,0,m_value.attr_max_len);
+	m_value.attr_len = 0;
+}
+
 void BLEDescriptor::setAccessPermissions(esp_gatt_perm_t perm) {
 	m_permissions = perm;
 }

libraries/BLE/src/BLEDescriptor.h

@@ -28,10 +28,13 @@ class BLEDescriptor {
 	BLEDescriptor(BLEUUID uuid, uint16_t max_len = 100);
 	virtual ~BLEDescriptor();
 
+
+
 	uint16_t getHandle();                                   // Get the handle of the descriptor.
 	size_t   getLength();                                   // Get the length of the value of the descriptor.
 	BLEUUID  getUUID();                                     // Get the UUID of the descriptor.
 	uint8_t* getValue();                                    // Get a pointer to the value of the descriptor.
+	bool resetsOnDisconnect();
 	void handleGATTServerEvent(
 			esp_gatts_cb_event_t      event,
 			esp_gatt_if_t             gatts_if,
@@ -41,12 +44,17 @@ class BLEDescriptor {
 	void setCallbacks(BLEDescriptorCallbacks* pCallbacks);  // Set callbacks to be invoked for the descriptor.
 	void setValue(uint8_t* data, size_t size);              // Set the value of the descriptor as a pointer to data.
 	void setValue(std::string value);                       // Set the value of the descriptor as a data buffer.
+	void setResetsOnDisconnect(bool flag);
 
 	std::string toString();                                 // Convert the descriptor to a string representation.
 
+protected:
+	void resetValue();										// Resets the values to its default
+
 private:
 	friend class BLEDescriptorMap;
 	friend class BLECharacteristic;
+	bool					m_resetValuesOnDisconnect;
 	BLEUUID                 m_bleUUID;
 	uint16_t                m_handle;
 	BLEDescriptorCallbacks* m_pCallback;