CameraService: Add unit test for stuck HAL at startup

New test verifies that getService is not called during camera service
startup, to make sure it can't get stuck if the camera HAL isn't
initializing properly.

Test: New test passes with new tryGetService code; test fails with
older camera service code.
Change-Id: I67b3fe392e8cc6961c33abf25e961a8e2df7d7b5

services/camera/libcameraservice/tests/CameraProviderManagerTest.cpp

@@ -183,6 +183,7 @@ struct TestInteractionProxy : public CameraProviderManager::ServiceInteractionPr
     sp<TestICameraProvider> mTestCameraProvider;
 
     TestInteractionProxy() {}
+
     void setProvider(sp<TestICameraProvider> provider) {
         mTestCameraProvider = provider;
     }
@@ -201,16 +202,29 @@ struct TestInteractionProxy : public CameraProviderManager::ServiceInteractionPr
 
     virtual sp<hardware::camera::provider::V2_4::ICameraProvider> tryGetService(
             const std::string &serviceName) override {
+        // If no provider has been given, act like the HAL isn't available and return null.
+        if (mTestCameraProvider == nullptr) return nullptr;
         return getService(serviceName);
     }
 
     virtual sp<hardware::camera::provider::V2_4::ICameraProvider> getService(
             const std::string &serviceName) override {
+        // If no provider has been given, fail; in reality, getService would
+        // block for HALs that don't start correctly, so we should never use
+        // getService when we don't have a valid HAL running
+        if (mTestCameraProvider == nullptr) {
+            ADD_FAILURE() << "getService called with no valid provider; would block indefinitely";
+            // Real getService would block, but that's bad in unit tests. So
+            // just record an error and return nullptr
+            return nullptr;
+        }
         mLastRequestedServiceNames.push_back(serviceName);
         return mTestCameraProvider;
     }
 
     virtual hardware::hidl_vec<hardware::hidl_string> listServices() override {
+        // Always provide a list even if there's no actual provider yet, to
+        // simulate stuck HAL situations as well
         hardware::hidl_vec<hardware::hidl_string> ret = {"test/0"};
         return ret;
     }
@@ -443,3 +457,52 @@ TEST(CameraProviderManagerTest, NotifyStateChangeTest) {
             << "Unable to change device state";
 
 }
+
+// Test that CameraProviderManager doesn't get stuck when the camera HAL isn't really working
+TEST(CameraProviderManagerTest, BadHalStartupTest) {
+
+    std::vector<hardware::hidl_string> deviceNames;
+    deviceNames.push_back("device@3.2/test/0");
+    deviceNames.push_back("device@1.0/test/0");
+    deviceNames.push_back("device@3.2/test/1");
+    hardware::hidl_vec<common::V1_0::VendorTagSection> vendorSection;
+    status_t res;
+
+    sp<CameraProviderManager> providerManager = new CameraProviderManager();
+    sp<TestStatusListener> statusListener = new TestStatusListener();
+    TestInteractionProxy serviceProxy;
+    sp<TestICameraProvider> provider =  new TestICameraProvider(deviceNames,
+            vendorSection);
+
+    // Not setting up provider in the service proxy yet, to test cases where a
+    // HAL isn't starting right
+    res = providerManager->initialize(statusListener, &serviceProxy);
+    ASSERT_EQ(res, OK) << "Unable to initialize provider manager";
+
+    // Now set up provider and trigger a registration
+    serviceProxy.setProvider(provider);
+    int numProviders = static_cast<int>(serviceProxy.listServices().size());
+
+    hardware::hidl_string testProviderFqInterfaceName =
+            "android.hardware.camera.provider@2.4::ICameraProvider";
+    hardware::hidl_string testProviderInstanceName = "test/0";
+    serviceProxy.mManagerNotificationInterface->onRegistration(
+            testProviderFqInterfaceName,
+            testProviderInstanceName, false);
+
+    // Check that new provider is called once for all the init methods
+    EXPECT_EQ(provider->mCalledCounter[TestICameraProvider::SET_CALLBACK], numProviders) <<
+            "Only one call to setCallback per provider expected during register";
+    EXPECT_EQ(provider->mCalledCounter[TestICameraProvider::GET_VENDOR_TAGS], numProviders) <<
+            "Only one call to getVendorTags per provider expected during register";
+    EXPECT_EQ(provider->mCalledCounter[TestICameraProvider::IS_SET_TORCH_MODE_SUPPORTED],
+            numProviders) <<
+            "Only one call to isSetTorchModeSupported per provider expected during init";
+    EXPECT_EQ(provider->mCalledCounter[TestICameraProvider::GET_CAMERA_ID_LIST], numProviders) <<
+            "Only one call to getCameraIdList per provider expected during init";
+    EXPECT_EQ(provider->mCalledCounter[TestICameraProvider::NOTIFY_DEVICE_STATE], numProviders) <<
+            "Only one call to notifyDeviceState per provider expected during init";
+
+    ASSERT_EQ(serviceProxy.mLastRequestedServiceNames.back(), testProviderInstanceName) <<
+            "Incorrect instance requested from service manager";
+}