Don't send fatal uncaught exception if an NDK crash exists

firebase-crashlytics-ndk/src/main/java/com/google/firebase/crashlytics/ndk/FirebaseCrashlyticsNdk.java

@@ -49,6 +49,7 @@ private interface SignalHandlerInstaller {
   }
 
   private boolean installHandlerDuringPrepareSession;
+  private String currentSessionId;
   private SignalHandlerInstaller signalHandlerInstaller;
 
   FirebaseCrashlyticsNdk(
@@ -57,6 +58,11 @@ private interface SignalHandlerInstaller {
     this.installHandlerDuringPrepareSession = installHandlerDuringPrepareSession;
   }
 
+  @Override
+  public boolean hasCrashDataForCurrentSession() {
+    return currentSessionId != null && hasCrashDataForSession(currentSessionId);
+  }
+
   @Override
   public boolean hasCrashDataForSession(@NonNull String sessionId) {
     return controller.hasCrashDataForSession(sessionId);
@@ -74,6 +80,7 @@ public synchronized void prepareNativeSession(
       long startedAtSeconds,
       @NonNull StaticSessionData sessionData) {
 
+    currentSessionId = sessionId;
     signalHandlerInstaller =
         () -> {
           Logger.getLogger().d("Initializing native session: " + sessionId);

firebase-crashlytics/src/main/java/com/google/firebase/crashlytics/internal/CrashlyticsNativeComponent.java

@@ -19,6 +19,8 @@
 
 public interface CrashlyticsNativeComponent {
 
+  boolean hasCrashDataForCurrentSession();
+
   boolean hasCrashDataForSession(@NonNull String sessionId);
 
   /**

firebase-crashlytics/src/main/java/com/google/firebase/crashlytics/internal/CrashlyticsNativeComponentDeferredProxy.java

@@ -40,6 +40,12 @@ public CrashlyticsNativeComponentDeferredProxy(
         });
   }
 
+  @Override
+  public boolean hasCrashDataForCurrentSession() {
+    CrashlyticsNativeComponent component = availableNativeComponent.get();
+    return component != null && component.hasCrashDataForCurrentSession();
+  }
+
   @Override
   public boolean hasCrashDataForSession(@NonNull String sessionId) {
     CrashlyticsNativeComponent component = availableNativeComponent.get();

firebase-crashlytics/src/main/java/com/google/firebase/crashlytics/internal/common/CrashlyticsController.java

@@ -156,7 +156,8 @@ public void onUncaughtException(
           }
         };
     crashHandler =
-        new CrashlyticsUncaughtExceptionHandler(crashListener, settingsProvider, defaultHandler);
+        new CrashlyticsUncaughtExceptionHandler(
+            crashListener, settingsProvider, defaultHandler, nativeComponent);
     Thread.setDefaultUncaughtExceptionHandler(crashHandler);
   }
 

firebase-crashlytics/src/main/java/com/google/firebase/crashlytics/internal/common/CrashlyticsUncaughtExceptionHandler.java

@@ -14,44 +14,47 @@
 
 package com.google.firebase.crashlytics.internal.common;
 
+import com.google.firebase.crashlytics.internal.CrashlyticsNativeComponent;
 import com.google.firebase.crashlytics.internal.Logger;
 import com.google.firebase.crashlytics.internal.settings.SettingsDataProvider;
 import java.util.concurrent.atomic.AtomicBoolean;
 
 class CrashlyticsUncaughtExceptionHandler implements Thread.UncaughtExceptionHandler {
 
   interface CrashListener {
+
     void onUncaughtException(
         SettingsDataProvider settingsDataProvider, Thread thread, Throwable ex);
   }
 
   private final CrashListener crashListener;
   private final SettingsDataProvider settingsDataProvider;
   private final Thread.UncaughtExceptionHandler defaultHandler;
+  private final CrashlyticsNativeComponent nativeComponent;
 
   // use AtomicBoolean because value is accessible from other threads.
   private final AtomicBoolean isHandlingException;
 
   public CrashlyticsUncaughtExceptionHandler(
       CrashListener crashListener,
       SettingsDataProvider settingsProvider,
-      Thread.UncaughtExceptionHandler defaultHandler) {
+      Thread.UncaughtExceptionHandler defaultHandler,
+      CrashlyticsNativeComponent nativeComponent) {
     this.crashListener = crashListener;
     this.settingsDataProvider = settingsProvider;
     this.defaultHandler = defaultHandler;
     this.isHandlingException = new AtomicBoolean(false);
+    this.nativeComponent = nativeComponent;
   }
 
   @Override
   public void uncaughtException(Thread thread, Throwable ex) {
     isHandlingException.set(true);
     try {
-      if (thread == null) {
-        Logger.getLogger().e("Could not handle uncaught exception; null thread");
-      } else if (ex == null) {
-        Logger.getLogger().e("Could not handle uncaught exception; null throwable");
-      } else {
+      if (shouldRecordUncaughtException(thread, ex)) {
         crashListener.onUncaughtException(settingsDataProvider, thread, ex);
+      } else {
+        Logger.getLogger().d("Uncaught exception will not be recorded by Crashlytics.");
       }
     } catch (Exception e) {
       Logger.getLogger().e("An error occurred in the uncaught exception handler", e);
@@ -65,4 +68,31 @@ public void uncaughtException(Thread thread, Throwable ex) {
   boolean isHandlingException() {
     return isHandlingException.get();
   }
+
+  /**
+   * Returns true if Crashlytics should record this exception. The decision to record is different
+   * than the decision to report the exception to Crashlytics servers, which is handled by the
+   * {@link DataCollectionArbiter}
+   *
+   * @return false if the thread or exception is null, or if a native crash already exists for this
+   *     session.
+   */
+  private boolean shouldRecordUncaughtException(Thread thread, Throwable ex) {
+    if (thread == null) {
+      Logger.getLogger().e("Crashlytics will not record uncaught exception; null thread");
+      return false;
+    }
+    if (ex == null) {
+      Logger.getLogger().e("Crashlytics will not record uncaught exception; null throwable");
+      return false;
+    }
+    // We should only report at most one fatal event for a session. If a native fatal already exists
+    // for this session, ignore the uncaught exception
+    if (nativeComponent.hasCrashDataForCurrentSession()) {
+      Logger.getLogger()
+          .d("Crashlytics will not record uncaught exception; native crash exists for session.");
+      return false;
+    }
+    return true;
+  }
 }