Correct ExternaVR shutdown. Fixes #538

MozillaReality · Sep 19, 2018 · 096dc2e · 096dc2e
1 parent 34ab2af
commit 096dc2e
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Showing 4 changed files with 25 additions and 3 deletions.
diff --git a/app/src/common/shared/org/mozilla/vrbrowser/VRBrowserActivity.java b/app/src/common/shared/org/mozilla/vrbrowser/VRBrowserActivity.java
@@ -217,8 +217,6 @@ protected void onDestroy() {
 
         SessionStore.get().clearListeners();
         super.onDestroy();
-        // FIXME: HACK TO KILL GECKO BETWEEN RUNS.
-        android.os.Process.killProcess(android.os.Process.myPid());
     }
 
     @Override

diff --git a/app/src/main/cpp/BrowserWorld.cpp b/app/src/main/cpp/BrowserWorld.cpp
@@ -534,6 +534,9 @@ void
 BrowserWorld::ShutdownJava() {
   ASSERT_ON_RENDER_THREAD();
   VRB_LOG("BrowserWorld::ShutdownJava");
+  if (m.externalVR) {
+    m.externalVR->Shutdown();
+  }
   GeckoSurfaceTexture::ShutdownJava();
   VRBrowser::ShutdownJava();
   if (m.env) {

diff --git a/app/src/main/cpp/ExternalVR.cpp b/app/src/main/cpp/ExternalVR.cpp
@@ -420,6 +420,26 @@ ExternalVR::StopPresenting() {
   m.waitingForExit = true;
 }
 
+void
+ExternalVR::Shutdown() {
+  m.system.displayState.shutdown = true;
+  m.system.displayState.mSuppressFrames = true;
+  PushSystemState();
+
+  // Wait until Gecko has processed the shutdown message
+  // Otherwise the shmem data may be deallocated before Gecko processes it, leading to undefined behaviour
+  Wait wait(m.data.browserMutex, m.data.browserCond);
+  wait.Lock();
+  m.PullBrowserStateWhileLocked();
+  while (!m.data.browserState.shutdown) {
+    if (!wait.DoWait(0.1)) {
+      VRB_WARN("FXR Shutdown wait timeout");
+      break;
+    }
+    m.PullBrowserStateWhileLocked();
+  }
+}
+
 ExternalVR::ExternalVR(State& aState) : m(aState) {
   PushSystemState();
 }

diff --git a/app/src/main/cpp/ExternalVR.h b/app/src/main/cpp/ExternalVR.h
@@ -40,6 +40,7 @@ class ExternalVR : public ImmersiveDisplay {
                       const double aBottomDegrees) override;
   void SetEyeOffset(const device::Eye aEye, const float aX, const float aY, const float aZ) override;
   void SetEyeResolution(const int32_t aX, const int32_t aY) override;
+  void CompleteEnumeration() override;
   // ExternalVR interface
   void PushSystemState();
   void PullBrowserState();
@@ -50,7 +51,7 @@ class ExternalVR : public ImmersiveDisplay {
   bool WaitFrameResult();
   void GetFrameResult(int32_t& aSurfaceHandle, device::EyeRect& aLeftEye, device::EyeRect& aRightEye) const;
   void StopPresenting();
-  void CompleteEnumeration() override;
+  void Shutdown();
 protected:
   struct State;
   ExternalVR(State& aState);