[Linux] Start/Stop BLE scan when going to sleep

Author: tim-gromeyer

linux/CMakeLists.txt

@@ -34,6 +34,7 @@ qt_add_executable(librepods
     eardetection.hpp
     media/playerstatuswatcher.cpp
     media/playerstatuswatcher.h
+    systemsleepmonitor.hpp
 )
 
 qt_add_qml_module(librepods

linux/ble/blemanager.cpp

@@ -112,6 +112,11 @@ void BleManager::stopScan()
     discoveryAgent->stop();
 }
 
+bool BleManager::isScanning() const
+{
+    return discoveryAgent->isActive();
+}
+
 void BleManager::onDeviceDiscovered(const QBluetoothDeviceInfo &info)
 {
     // Check for Apple's manufacturer ID (0x004C)

linux/ble/blemanager.h

@@ -72,6 +72,7 @@ class BleManager : public QObject
 
     void startScan();
     void stopScan();
+    bool isScanning() const;
 
 private slots:
     void onDeviceDiscovered(const QBluetoothDeviceInfo &info);

linux/main.cpp

@@ -24,6 +24,7 @@
 #include "ble/blemanager.h"
 #include "ble/bleutils.h"
 #include "QRCodeImageProvider.hpp"
+#include "systemsleepmonitor.hpp"
 
 using namespace AirpodsTrayApp::Enums;
 
@@ -45,6 +46,7 @@ class AirPodsTrayApp : public QObject {
         : QObject(parent), debugMode(debugMode), m_settings(new QSettings("AirPodsTrayApp", "AirPodsTrayApp"))
         , m_autoStartManager(new AutoStartManager(this)), m_hideOnStart(hideOnStart), parent(parent)
         , m_deviceInfo(new DeviceInfo(this)), m_bleManager(new BleManager(this))
+        , m_systemSleepMonitor(new SystemSleepMonitor(this))
     {
         QLoggingCategory::setFilterRules(QString("airpodsApp.debug=%1").arg(debugMode ? "true" : "false"));
         LOG_INFO("Initializing AirPodsTrayApp");
@@ -74,6 +76,8 @@ class AirPodsTrayApp : public QObject {
 
         connect(m_bleManager, &BleManager::deviceFound, this, &AirPodsTrayApp::bleDeviceFound);
         connect(m_deviceInfo->getBattery(), &Battery::primaryChanged, this, &AirPodsTrayApp::primaryChanged);
+        connect(m_systemSleepMonitor, &SystemSleepMonitor::systemGoingToSleep, this, &AirPodsTrayApp::onSystemGoingToSleep);
+        connect(m_systemSleepMonitor, &SystemSleepMonitor::systemWakingUp, this, &AirPodsTrayApp::onSystemWakingUp);
 
         // Load settings
         CrossDevice.isEnabled = loadCrossDeviceEnabled();
@@ -333,6 +337,20 @@ public slots:
     int loadRetryAttempts() const { return m_settings->value("bluetooth/retryAttempts", 3).toInt(); }
     void saveRetryAttempts(int attempts) { m_settings->setValue("bluetooth/retryAttempts", attempts); }
 
+    void onSystemGoingToSleep()
+    {
+        if (m_bleManager->isScanning())
+        {
+            LOG_INFO("Stopping BLE scan before going to sleep");
+            m_bleManager->stopScan();
+        }
+    }
+    void onSystemWakingUp()
+    {
+        LOG_INFO("System is waking up, starting ble scan");
+        m_bleManager->startScan();
+    }
+
 private slots:
     void onTrayIconActivated()
     {
@@ -851,6 +869,7 @@ private slots:
     bool m_hideOnStart = false;
     DeviceInfo *m_deviceInfo;
     BleManager *m_bleManager;
+    SystemSleepMonitor *m_systemSleepMonitor = nullptr;
 };
 
 int main(int argc, char *argv[]) {

linux/systemsleepmonitor.hpp

@@ -0,0 +1,49 @@
+#ifndef SYSTEMSLEEPMONITOR_HPP
+#define SYSTEMSLEEPMONITOR_HPP
+
+#include <QObject>
+#include <QDBusConnection>
+#include <QDBusInterface>
+#include <QDBusMessage>
+#include <QDebug>
+
+class SystemSleepMonitor : public QObject {
+    Q_OBJECT
+
+public:
+    explicit SystemSleepMonitor(QObject *parent = nullptr) : QObject(parent) {
+        // Connect to the system D-Bus
+        QDBusConnection systemBus = QDBusConnection::systemBus();
+        if (!systemBus.isConnected()) {
+            qWarning() << "Cannot connect to system D-Bus";
+            return;
+        }
+
+        // Subscribe to PrepareForSleep signal from logind
+        systemBus.connect(
+            "org.freedesktop.login1",
+            "/org/freedesktop/login1",
+            "org.freedesktop.login1.Manager",
+            "PrepareForSleep",
+            this,
+            SLOT(handlePrepareForSleep(bool))
+        );
+    }
+
+    ~SystemSleepMonitor() override = default;
+
+signals:
+    void systemGoingToSleep();
+    void systemWakingUp();
+
+private slots:
+    void handlePrepareForSleep(bool sleeping) {
+        if (sleeping) {
+            emit systemGoingToSleep();
+        } else {
+            emit systemWakingUp();
+        }
+    }
+};
+
+#endif // SYSTEMSLEEPMONITOR_HPP