[dbus] add notifications for active dataset changes (openthread#26) (o…

…penthread#28)

* [dbus] add notifications for active dataset changes

* Fix error log

* Fix style

(cherry picked from commit 2f878e2297ba6277e17fb56da0cfb772e5ccd4d4)

src/agent/thread_helper.cpp

@@ -82,6 +82,30 @@ void ThreadHelper::StateChangedCallback(otChangedFlags aFlags)
             }
         }
     }
+
+    if (aFlags & OT_CHANGED_ACTIVE_DATASET)
+    {
+        ActiveDatasetChangedCallback();
+    }
+}
+
+void ThreadHelper::ActiveDatasetChangedCallback()
+{
+    otError                  error;
+    otOperationalDatasetTlvs datasetTlvs;
+
+    SuccessOrExit(error = otDatasetGetActiveTlvs(mInstance, &datasetTlvs));
+
+    for (const auto &handler : mActiveDatasetChangeHandlers)
+    {
+        handler(datasetTlvs);
+    }
+
+exit:
+    if (error != OT_ERROR_NONE)
+    {
+        otbrLogWarning("Error handling active dataset change: %s", otThreadErrorToString(error));
+    }
 }
 
 void ThreadHelper::AddDeviceRoleHandler(DeviceRoleHandler aHandler)
@@ -446,5 +470,10 @@ otError ThreadHelper::PermitUnsecureJoin(uint16_t aPort, uint32_t aSeconds)
 }
 #endif
 
+void ThreadHelper::AddActiveDatasetChangeHandler(DatasetChangeHandler aHandler)
+{
+    mActiveDatasetChangeHandlers.push_back(std::move(aHandler));
+}
+
 } // namespace agent
 } // namespace otbr

src/agent/thread_helper.hpp

@@ -63,9 +63,10 @@ namespace agent {
 class ThreadHelper
 {
 public:
-    using DeviceRoleHandler = std::function<void(otDeviceRole)>;
-    using ScanHandler       = std::function<void(otError, const std::vector<otActiveScanResult> &)>;
-    using ResultHandler     = std::function<void(otError)>;
+    using DeviceRoleHandler    = std::function<void(otDeviceRole)>;
+    using ScanHandler          = std::function<void(otError, const std::vector<otActiveScanResult> &)>;
+    using ResultHandler        = std::function<void(otError)>;
+    using DatasetChangeHandler = std::function<void(const otOperationalDatasetTlvs &)>;
 
     /**
      * The constructor of a Thread helper.
@@ -84,6 +85,13 @@ class ThreadHelper
      */
     void AddDeviceRoleHandler(DeviceRoleHandler aHandler);
 
+    /**
+     * This method adds a callback for active dataset change.
+     *
+     * @param[in]  aHandler   The active dataset change handler.
+     */
+    void AddActiveDatasetChangeHandler(DatasetChangeHandler aHandler);
+
     /**
      * This method permits unsecure join on port.
      *
@@ -217,14 +225,17 @@ class ThreadHelper
     void    RandomFill(void *aBuf, size_t size);
     uint8_t RandomChannelFromChannelMask(uint32_t aChannelMask);
 
+    void ActiveDatasetChangedCallback();
+
     otInstance *mInstance;
 
     otbr::Ncp::ControllerOpenThread *mNcp;
 
     ScanHandler                     mScanHandler;
     std::vector<otActiveScanResult> mScanResults;
 
-    std::vector<DeviceRoleHandler> mDeviceRoleHandlers;
+    std::vector<DeviceRoleHandler>    mDeviceRoleHandlers;
+    std::vector<DatasetChangeHandler> mActiveDatasetChangeHandlers;
 
     std::map<uint16_t, size_t> mUnsecurePortRefCounter;
 

src/dbus/server/dbus_thread_object.cpp

@@ -105,6 +105,7 @@ otbrError DBusThreadObject::Init(void)
     auto      threadHelper = mNcp->GetThreadHelper();
 
     threadHelper->AddDeviceRoleHandler(std::bind(&DBusThreadObject::DeviceRoleHandler, this, _1));
+    threadHelper->AddActiveDatasetChangeHandler(std::bind(&DBusThreadObject::ActiveDatasetChangeHandler, this, _1));
     mNcp->RegisterResetHandler(std::bind(&DBusThreadObject::NcpResetHandler, this));
 
     RegisterMethod(OTBR_DBUS_THREAD_INTERFACE, OTBR_DBUS_SCAN_METHOD,
@@ -215,6 +216,8 @@ void DBusThreadObject::DeviceRoleHandler(otDeviceRole aDeviceRole)
 void DBusThreadObject::NcpResetHandler(void)
 {
     mNcp->GetThreadHelper()->AddDeviceRoleHandler(std::bind(&DBusThreadObject::DeviceRoleHandler, this, _1));
+    mNcp->GetThreadHelper()->AddActiveDatasetChangeHandler(
+        std::bind(&DBusThreadObject::ActiveDatasetChangeHandler, this, _1));
     SignalPropertyChanged(OTBR_DBUS_THREAD_INTERFACE, OTBR_DBUS_PROPERTY_DEVICE_ROLE,
                           GetDeviceRoleName(OT_DEVICE_ROLE_DISABLED));
 }
@@ -1053,5 +1056,12 @@ otError DBusThreadObject::GetRadioRegionHandler(DBusMessageIter &aIter)
     return error;
 }
 
+void DBusThreadObject::ActiveDatasetChangeHandler(const otOperationalDatasetTlvs &aDatasetTlvs)
+{
+    std::vector<uint8_t> value(aDatasetTlvs.mLength);
+    std::copy(aDatasetTlvs.mTlvs, aDatasetTlvs.mTlvs + aDatasetTlvs.mLength, value.begin());
+    SignalPropertyChanged(OTBR_DBUS_THREAD_INTERFACE, OTBR_DBUS_PROPERTY_ACTIVE_DATASET_TLVS, value);
+}
+
 } // namespace DBus
 } // namespace otbr

src/dbus/server/dbus_thread_object.hpp

@@ -82,6 +82,7 @@ class DBusThreadObject : public DBusObject
 
 private:
     void DeviceRoleHandler(otDeviceRole aDeviceRole);
+    void ActiveDatasetChangeHandler(const otOperationalDatasetTlvs &aDatasetTlvs);
     void NcpResetHandler(void);
 
     void ScanHandler(DBusRequest &aRequest);