EmulatedCamera: Pass dedicated sensor handler to sensor manager

Passing a direct 'EmulatedScene' reference to sensor manager
can extend its lifetime and prevent 'EmulatedSensor' from
releasing the sensor event queue resources.
Avoid this by using a dedicated sensor event handler which
will not interfere with the scene lifetime.
Additionally correct possible invalid access during sensor
start up.

Bug: 156290263
Test: Camera CTS
Change-Id: I32c178650584bc51468ebc663edc57c0ce6761d2

3 files changed, 34 insertions, 21 deletions

diff --git a/devices/EmulatedCamera/hwl/EmulatedScene.cpp b/devices/EmulatedCamera/hwl/EmulatedScene.cpp
index cfd1602..df0c9f2 100644
--- a/devices/EmulatedCamera/hwl/EmulatedScene.cpp
+++ b/devices/EmulatedCamera/hwl/EmulatedScene.cpp
@@ -137,7 +137,12 @@ void EmulatedScene::Initialize(int sensor_width_px, int sensor_height_px,
 
 }
 
-Return<void> EmulatedScene::onEvent(const Event &e) {
+Return<void> EmulatedScene::SensorHandler::onEvent(const Event& e) {
+  auto scene = scene_.promote();
+  if (scene.get() == nullptr) {
+    return Void();
+  }
+
   if (e.sensorType == SensorType::ACCELEROMETER) {
     // Heuristic approach for deducing the screen
     // rotation depending on the reported
@@ -149,13 +154,13 @@ Return<void> EmulatedScene::onEvent(const Event &e) {
     uint32_t x_accel = e.u.vec3.x;
     uint32_t y_accel = e.u.vec3.y;
     if (x_accel == earth_accel) {
-      screen_rotation_ = 270;
+      scene->screen_rotation_ = 270;
     } else if (x_accel == -earth_accel) {
-      screen_rotation_ = 90;
+      scene->screen_rotation_ = 90;
     } else if (y_accel == -earth_accel) {
-      screen_rotation_ = 180;
+      scene->screen_rotation_ = 180;
     } else {
-      screen_rotation_ = 0;
+      scene->screen_rotation_ = 0;
     }
   } else {
     ALOGE("%s: unexpected event received type: %d", __func__, e.sensorType);
@@ -446,8 +451,8 @@ void EmulatedScene::InitializeSensorQueue() {
           }
         }});
     if (sensor_found) {
-      manager->createEventQueue(this,
-          [&] (const auto &q, auto result) {
+      manager->createEventQueue(
+          new SensorHandler(this), [&](const auto& q, auto result) {
             if (result != Result::OK) {
               ALOGE("%s: Cannot create event queue", __func__);
               return;
diff --git a/devices/EmulatedCamera/hwl/EmulatedScene.h b/devices/EmulatedCamera/hwl/EmulatedScene.h
index 2eb92fa..e3a5238 100644
--- a/devices/EmulatedCamera/hwl/EmulatedScene.h
+++ b/devices/EmulatedCamera/hwl/EmulatedScene.h
@@ -38,7 +38,7 @@ using ::android::hardware::sensors::V1_0::Event;
 using ::android::hardware::Return;
 using ::android::hardware::Void;
 
-class EmulatedScene : public IEventQueueCallback {
+class EmulatedScene : public RefBase {
  public:
   EmulatedScene(int sensor_width_px, int sensor_height_px,
                 float sensor_sensitivity, int sensor_orientation,
@@ -86,15 +86,24 @@ class EmulatedScene : public IEventQueueCallback {
   // indexed with ColorChannels.
   const uint32_t* GetPixelElectronsColumn();
 
-  // IEventQueueCallback interface
-  Return<void> onEvent(const Event &e) override;
-
   enum ColorChannels { R = 0, Gr, Gb, B, Y, Cb, Cr, NUM_CHANNELS };
 
   static const int kSceneWidth = 20;
   static const int kSceneHeight = 20;
 
  private:
+  class SensorHandler : public IEventQueueCallback {
+   public:
+    SensorHandler(wp<EmulatedScene> scene) : scene_(scene) {
+    }
+
+    // IEventQueueCallback interface
+    Return<void> onEvent(const Event& e) override;
+
+   private:
+    wp<EmulatedScene> scene_;
+  };
+
   void InitiliazeSceneRotation(bool clock_wise);
   void InitializeSensorQueue();
 
@@ -204,7 +213,7 @@ class EmulatedScene : public IEventQueueCallback {
   static const uint8_t kMaterialsFlags[NUM_MATERIALS];
 
   static const uint8_t kScene[];
-  };
+};
 
 }  // namespace android
 
diff --git a/devices/EmulatedCamera/hwl/EmulatedSensor.cpp b/devices/EmulatedCamera/hwl/EmulatedSensor.cpp
index 794abd2..4eb6926 100644
--- a/devices/EmulatedCamera/hwl/EmulatedSensor.cpp
+++ b/devices/EmulatedCamera/hwl/EmulatedSensor.cpp
@@ -346,15 +346,16 @@ status_t EmulatedSensor::StartUp(
     return BAD_VALUE;
   }
 
-  auto device_chars = logical_chars->find(logical_camera_id);
-  if (device_chars == logical_chars->end()) {
+  chars_ = std::move(logical_chars);
+  auto device_chars = chars_->find(logical_camera_id);
+  if (device_chars == chars_->end()) {
     ALOGE(
         "%s: Logical camera id: %u absent from logical camera characteristics!",
         __FUNCTION__, logical_camera_id);
     return BAD_VALUE;
   }
 
-  for (const auto& it : *logical_chars) {
+  for (const auto& it : *chars_) {
     if (!AreCharacteristicsSupported(it.second)) {
       ALOGE("%s: Sensor characteristics for camera id: %u not supported!",
             __FUNCTION__, it.first);
@@ -363,12 +364,10 @@ status_t EmulatedSensor::StartUp(
   }
 
   logical_camera_id_ = logical_camera_id;
-  chars_ = std::move(logical_chars);
-  scene_ = new EmulatedScene(device_chars->second.width,
-                             device_chars->second.height,
-                             kElectronsPerLuxSecond,
-                             device_chars->second.orientation,
-                             device_chars->second.is_front_facing);
+  scene_ = new EmulatedScene(
+      device_chars->second.width, device_chars->second.height,
+      kElectronsPerLuxSecond, device_chars->second.orientation,
+      device_chars->second.is_front_facing);
   jpeg_compressor_ = std::make_unique<JpegCompressor>();
 
   auto res = run(LOG_TAG, ANDROID_PRIORITY_URGENT_DISPLAY);