BLE Library onRead Callback fix and Client disconnect feature (espressif#2913)

* BLEServer::disconnect() * Invoke Read callback first, to make data update possible before read

Author: romansavrulin

libraries/BLE/src/BLECharacteristic.cpp

@@ -378,6 +378,10 @@ 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.
+}
+
 std::string value = m_value.getValue();
 
 if (value.length() + 1 > maxOffset) {
@@ -392,10 +396,6 @@ void BLECharacteristic::handleGATTServerEvent(
 rsp.attr_value.offset = 0;
 memcpy(rsp.attr_value.value, value.data(), rsp.attr_value.len);
 }
-
-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.
-}
 }
 rsp.attr_value.handle = param->read.handle;
 rsp.attr_value.auth_req = ESP_GATT_AUTH_REQ_NONE;

libraries/BLE/src/BLEServer.cpp

@@ -412,4 +412,9 @@ void BLEServer::updateConnParams(esp_bd_addr_t remote_bda, uint16_t minInterval,
 conn_params.timeout = timeout; // timeout = 400*10ms = 4000ms
 esp_ble_gap_update_conn_params(&conn_params); 
 }
+
+void BLEServer::disconnect(uint16_t connId) {
+esp_ble_gatts_close(m_gatts_if, connId);
+}
+
 #endif // CONFIG_BT_ENABLED

libraries/BLE/src/BLEServer.h

@@ -72,6 +72,7 @@ class BLEServer {
 BLEService* getServiceByUUID(const char* uuid);
 BLEService* getServiceByUUID(BLEUUID uuid);
 bool connect(BLEAddress address);
+void disconnect(uint16_t connId);
 uint16_tm_appId;
 voidupdateConnParams(esp_bd_addr_t remote_bda, uint16_t minInterval, uint16_t maxInterval, uint16_t latency, uint16_t timeout);