Ble notification/indication status and timeout (#2998)

* add timed wait

* Added Notification/Indication data and status callbacks

* imply null-object pattern for BLE callback

Author: romansavrulin

libraries/BLE/src/BLECharacteristic.cpp

@@ -22,6 +22,7 @@
 
 #define NULL_HANDLE (0xffff)
 
+static BLECharacteristicCallbacks defaultCallback; //null-object-pattern
 
 /**
  * @brief Construct a characteristic
@@ -40,7 +41,7 @@ BLECharacteristic::BLECharacteristic(BLEUUID uuid, uint32_t properties) {
 	m_bleUUID    = uuid;
 	m_handle     = NULL_HANDLE;
 	m_properties = (esp_gatt_char_prop_t)0;
-	m_pCallbacks = nullptr;
+	m_pCallbacks = &defaultCallback;
 
 	setBroadcastProperty((properties & PROPERTY_BROADCAST) != 0);
 	setReadProperty((properties & PROPERTY_READ) != 0);
@@ -220,9 +221,7 @@ void BLECharacteristic::handleGATTServerEvent(
 		case ESP_GATTS_EXEC_WRITE_EVT: {
 			if (param->exec_write.exec_write_flag == ESP_GATT_PREP_WRITE_EXEC) {
 				m_value.commit();
-				if (m_pCallbacks != nullptr) {
-					m_pCallbacks->onWrite(this); // Invoke the onWrite callback handler.
-				}
+				m_pCallbacks->onWrite(this); // Invoke the onWrite callback handler.
 			} else {
 				m_value.cancel();
 			}
@@ -307,7 +306,7 @@ void BLECharacteristic::handleGATTServerEvent(
 					}
 				} // Response needed
 
-				if (m_pCallbacks != nullptr && param->write.is_prep != true) {
+				if (param->write.is_prep != true) {
 					m_pCallbacks->onWrite(this); // Invoke the onWrite callback handler.
 				}
 			} // Match on handles.
@@ -378,9 +377,9 @@ void BLECharacteristic::handleGATTServerEvent(
 						}
 					} else { // read.is_long == false
 
-						if (m_pCallbacks != nullptr) {  // If is.long is false then this is the first (or only) request to read data, so invoke the callback
-							m_pCallbacks->onRead(this);   // Invoke the read callback.
-						}
+						// If is.long is false then this is the first (or only) request to read data, so invoke the callback
+						// Invoke the read callback.
+						m_pCallbacks->onRead(this);
 
 						std::string value = m_value.getValue();
 
@@ -480,10 +479,13 @@ void BLECharacteristic::notify(bool is_notification) {
 	assert(getService() != nullptr);
 	assert(getService()->getServer() != nullptr);
 
+	m_pCallbacks->onNotify(this);   // Invoke the notify callback.
+
 	GeneralUtils::hexDump((uint8_t*)m_value.getValue().data(), m_value.getValue().length());
 
 	if (getService()->getServer()->getConnectedCount() == 0) {
 		log_v("<< notify: No connected clients.");
+		m_pCallbacks->onStatus(this, BLECharacteristicCallbacks::Status::ERROR_NO_CLIENT, 0);
 		return;
 	}
 
@@ -494,12 +496,14 @@ void BLECharacteristic::notify(bool is_notification) {
 	if(is_notification) {
 		if (p2902 != nullptr && !p2902->getNotifications()) {
 			log_v("<< notifications disabled; ignoring");
+			m_pCallbacks->onStatus(this, BLECharacteristicCallbacks::Status::ERROR_NOTIFY_DISABLED, 0);   // Invoke the notify callback.
 			return;
 		}
 	}
 	else{
 		if (p2902 != nullptr && !p2902->getIndications()) {
 			log_v("<< indications disabled; ignoring");
+			m_pCallbacks->onStatus(this, BLECharacteristicCallbacks::Status::ERROR_INDICATE_DISABLED, 0);   // Invoke the notify callback.
 			return;
 		}
 	}
@@ -510,7 +514,7 @@ void BLECharacteristic::notify(bool is_notification) {
 		}
 
 		size_t length = m_value.getValue().length();
-		if(!is_notification)
+		if(!is_notification) // is indication
 			m_semaphoreConfEvt.take("indicate");
 		esp_err_t errRc = ::esp_ble_gatts_send_indicate(
 				getService()->getServer()->getGattsIf(),
@@ -519,10 +523,23 @@ void BLECharacteristic::notify(bool is_notification) {
 		if (errRc != ESP_OK) {
 			log_e("<< esp_ble_gatts_send_ %s: rc=%d %s",is_notification?"notify":"indicate", errRc, GeneralUtils::errorToString(errRc));
 			m_semaphoreConfEvt.give();
+			m_pCallbacks->onStatus(this, BLECharacteristicCallbacks::Status::ERROR_GATT, errRc);   // Invoke the notify callback.
 			return;
 		}
-		if(!is_notification)
-			m_semaphoreConfEvt.wait("indicate");
+		if(!is_notification){ // is indication
+			if(!m_semaphoreConfEvt.timedWait("indicate", indicationTimeout)){
+				m_pCallbacks->onStatus(this, BLECharacteristicCallbacks::Status::ERROR_INDICATE_TIMEOUT, 0);   // Invoke the notify callback.
+			} else {
+				auto code = (esp_gatt_status_t) m_semaphoreConfEvt.value();
+				if(code == ESP_GATT_OK) {
+					m_pCallbacks->onStatus(this, BLECharacteristicCallbacks::Status::SUCCESS_INDICATE, code);   // Invoke the notify callback.
+				} else {
+					m_pCallbacks->onStatus(this, BLECharacteristicCallbacks::Status::ERROR_INDICATE_FAILURE, code);
+				}
+			}
+		} else {
+			m_pCallbacks->onStatus(this, BLECharacteristicCallbacks::Status::SUCCESS_NOTIFY, 0);   // Invoke the notify callback.
+		}
 	}
 	log_v("<< notify");
 } // Notify
@@ -551,7 +568,11 @@ void BLECharacteristic::setBroadcastProperty(bool value) {
  */
 void BLECharacteristic::setCallbacks(BLECharacteristicCallbacks* pCallbacks) {
 	log_v(">> setCallbacks: 0x%x", (uint32_t)pCallbacks);
-	m_pCallbacks = pCallbacks;
+	if (pCallbacks != nullptr){
+		m_pCallbacks = pCallbacks;
+	} else {
+		m_pCallbacks = &defaultCallback;
+	}
 	log_v("<< setCallbacks");
 } // setCallbacks
 
@@ -754,4 +775,27 @@ void BLECharacteristicCallbacks::onWrite(BLECharacteristic* pCharacteristic) {
 	log_d("BLECharacteristicCallbacks", "<< onWrite");
 } // onWrite
 
+
+/**
+ * @brief Callback function to support a Notify request.
+ * @param [in] pCharacteristic The characteristic that is the source of the event.
+ */
+void BLECharacteristicCallbacks::onNotify(BLECharacteristic* pCharacteristic) {
+	log_d("BLECharacteristicCallbacks", ">> onNotify: default");
+	log_d("BLECharacteristicCallbacks", "<< onNotify");
+} // onNotify
+
+
+/**
+ * @brief Callback function to support a Notify/Indicate Status report.
+ * @param [in] pCharacteristic The characteristic that is the source of the event.
+ * @param [in] s Status of the notification/indication
+ * @param [in] code Additional code of underlying errors
+ */
+void BLECharacteristicCallbacks::onStatus(BLECharacteristic* pCharacteristic, Status s, uint32_t code) {
+	log_d("BLECharacteristicCallbacks", ">> onStatus: default");
+	log_d("BLECharacteristicCallbacks", "<< onStatus");
+} // onStatus
+
+
 #endif /* CONFIG_BT_ENABLED */

libraries/BLE/src/BLECharacteristic.h

@@ -90,6 +90,8 @@ class BLECharacteristic {
 	static const uint32_t PROPERTY_INDICATE  = 1<<4;
 	static const uint32_t PROPERTY_WRITE_NR  = 1<<5;
 
+	static const uint32_t indicationTimeout = 1000;
+
 private:
 
 	friend class BLEServer;
@@ -130,9 +132,22 @@ class BLECharacteristic {
  */
 class BLECharacteristicCallbacks {
 public:
+	typedef enum {
+		SUCCESS_INDICATE,
+		SUCCESS_NOTIFY,
+		ERROR_INDICATE_DISABLED,
+		ERROR_NOTIFY_DISABLED,
+		ERROR_GATT,
+		ERROR_NO_CLIENT,
+		ERROR_INDICATE_TIMEOUT,
+		ERROR_INDICATE_FAILURE
+	}Status;
+
 	virtual ~BLECharacteristicCallbacks();
 	virtual void onRead(BLECharacteristic* pCharacteristic);
 	virtual void onWrite(BLECharacteristic* pCharacteristic);
+	virtual void onNotify(BLECharacteristic* pCharacteristic);
+	virtual void onStatus(BLECharacteristic* pCharacteristic, Status s, uint32_t code);
 };
 #endif /* CONFIG_BT_ENABLED */
 #endif /* COMPONENTS_CPP_UTILS_BLECHARACTERISTIC_H_ */

libraries/BLE/src/FreeRTOS.cpp

@@ -78,6 +78,38 @@ uint32_t FreeRTOS::Semaphore::wait(std::string owner) {
 	return m_value;
 } // wait
 
+/**
+ * @brief Wait for a semaphore to be released in a given period of time by trying to take it and
+ * then releasing it again. The value associated with the semaphore can be taken by value() call after return
+ * @param [in] owner A debug tag.
+ * @param [in] timeoutMs timeout to wait in ms.
+ * @return True if we took the semaphore within timeframe.
+ */
+bool FreeRTOS::Semaphore::timedWait(std::string owner, uint32_t timeoutMs) {
+	log_v(">> wait: Semaphore waiting: %s for %s", toString().c_str(), owner.c_str());
+
+	if (m_usePthreads && timeoutMs != portMAX_DELAY) {
+		assert(false);  // We apparently don't have a timed wait for pthreads.
+	}
+
+	auto ret = pdTRUE;
+
+	if (m_usePthreads) {
+		pthread_mutex_lock(&m_pthread_mutex);
+	} else {
+		ret = xSemaphoreTake(m_semaphore, timeoutMs);
+	}
+
+	if (m_usePthreads) {
+		pthread_mutex_unlock(&m_pthread_mutex);
+	} else {
+		xSemaphoreGive(m_semaphore);
+	}
+
+	log_v("<< wait: Semaphore %s released: %d", toString().c_str(), ret);
+	return ret;
+} // wait
+
 
 FreeRTOS::Semaphore::Semaphore(std::string name) {
 	m_usePthreads = false;   	// Are we using pThreads or FreeRTOS?

libraries/BLE/src/FreeRTOS.h

@@ -40,6 +40,8 @@ class FreeRTOS {
 		bool        take(uint32_t timeoutMs, std::string owner = "<Unknown>");
 		std::string toString();
 		uint32_t	wait(std::string owner = "<Unknown>");
+		bool		timedWait(std::string owner = "<Unknown>", uint32_t timeoutMs = portMAX_DELAY);
+		uint32_t	value(){ return m_value; };
 
 	private:
 		SemaphoreHandle_t m_semaphore;