Fixed crash when reporting device lost

PiperOrigin-RevId: 522615946

internal/platform/implementation/windows/ble_medium.cc

@@ -17,6 +17,7 @@
 #include <chrono>  // NOLINT
 #include <exception>
 #include <future>  // NOLINT
+#include <list>
 #include <memory>
 #include <string>
 #include <utility>
@@ -287,6 +288,7 @@ bool BleMedium::StartScanning(
     {
       absl::MutexLock lock(&peripheral_map_mutex_);
       peripheral_map_.clear();
+      lost_peripherals_.clear();
     }
 
     watcher_ = BluetoothLEAdvertisementWatcher();
@@ -596,6 +598,9 @@ void BleMedium::AdvertisementReceivedHandler(
                 /*ble_peripheral*/ *peripheral_map_[peripheral_name],
                 /*service_id*/ service_id_);
 
+            // put the lost peripheral in the lost peripheral list.
+            lost_peripherals_.push_back(
+                std::move(peripheral_map_[peripheral_name]));
           } else {
             // The device is already reported to discover, so don't need to
             // call it again.

internal/platform/implementation/windows/ble_medium.h

@@ -18,6 +18,7 @@
 #include <guiddef.h>
 
 #include <future>  //  NOLINT
+#include <list>
 #include <memory>
 #include <string>
 #include <utility>
@@ -102,6 +103,12 @@ class BleMedium : public api::BleMedium {
   absl::flat_hash_map<std::string, std::unique_ptr<BlePeripheral>>
       peripheral_map_ ABSL_GUARDED_BY(peripheral_map_mutex_);
 
+  // The platform implementation will reference lost peripheral in another
+  // thread after report loss, so we still need to keep the peripheral to
+  // avoid potential memory issues.
+  std::list<std::unique_ptr<BlePeripheral>> lost_peripherals_
+      ABSL_GUARDED_BY(peripheral_map_mutex_);
+
   // WinRT objects
   ::winrt::Windows::Devices::Bluetooth::Advertisement::
       BluetoothLEAdvertisementPublisher publisher_ = nullptr;