Fixing threading-related hang during initialization in urgent mode

Co-authored-by: wowlocal <kh.misha.9@icloud.com>

Crashlytics/Crashlytics/Controllers/FIRCLSReportUploader.m

@@ -89,9 +89,18 @@ - (void)prepareAndSubmitReport:(FIRCLSInternalReport *)report
       FIRCLSApplicationActivityDefault, @"Crashlytics Crash Report Processing", ^{
         // Check to see if the FID has rotated before we construct the payload
         // so that the payload has an updated value.
-        [self.installIDModel regenerateInstallIDIfNeededWithBlock:^(NSString *_Nonnull newFIID) {
-          self.fiid = [newFIID copy];
-        }];
+        //
+        // If we're in urgent mode, this will be running on the main thread. Since
+        // the FIID callback is run on the main thread, this call can deadlock in
+        // urgent mode. Since urgent mode happens when the app is in a crash loop,
+        // we can safely assume users aren't rotating their FIID, so this can be skipped.
+        if (!urgent) {
+          [self.installIDModel regenerateInstallIDIfNeededWithBlock:^(NSString *_Nonnull newFIID) {
+            self.fiid = [newFIID copy];
+          }];
+        } else {
+          FIRCLSWarningLog(@"Crashlytics skipped rotating the Install ID during urgent mode because it is run on the main thread, which can't succeed. This can happen if the app crashed the last run and Crashlytics is uploading urgently.");
+        }
 
         // Run on-device symbolication before packaging if we should process
         if (shouldProcess) {

Crashlytics/UnitTests/Data/GoogleService-Info.plist

@@ -0,0 +1,12 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
+<plist version="1.0">
+<dict>
+	<key>API_KEY</key>
+	<string>ATestTestTestTestTestTestTestTestTest00</string>
+	<key>PROJECT_ID</key>
+	<string>test-1aaaa</string>
+	<key>GOOGLE_APP_ID</key>
+	<string>1:632950151350:ios:d5b0d08d4f00f4b1</string>
+</dict>
+</plist>

Crashlytics/UnitTests/FIRCLSInstallIdentifierModelTests.m

@@ -66,8 +66,11 @@ - (void)testCreateUUIDAndRotate {
       [[FIRCLSInstallIdentifierModel alloc] initWithInstallations:iid];
   XCTAssertNotNil(model.installID);
 
-  BOOL didRotate = [model regenerateInstallIDIfNeededWithBlock:^(NSString *_Nonnull fiid){
-  }];
+  BOOL __block didRotate = true;
+//  dispatch_async_and_wait(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^(void){
+    didRotate = [model regenerateInstallIDIfNeededWithBlock:^(NSString *_Nonnull fiid){
+    }];
+//  });
   sleep(1);
 
   XCTAssertFalse(didRotate);

Crashlytics/UnitTests/FIRCLSReportUploaderTests.m

@@ -74,11 +74,12 @@ - (void)setUp {
 
 - (void)tearDown {
   self.uploader = nil;
+  [FIRApp resetApps];
 
   [super tearDown];
 }
 
-- (void)setupUploaderWithInstallations:(FIRMockInstallations *)installations {
+- (void)setupUploaderWithInstallations:(FIRInstallations *)installations {
   // Allow nil values only in tests
 #pragma clang diagnostic push
 #pragma clang diagnostic ignored "-Wnonnull"
@@ -95,17 +96,33 @@ - (void)setupUploaderWithInstallations:(FIRMockInstallations *)installations {
   self.uploader = [[FIRCLSReportUploader alloc] initWithManagerData:self.managerData];
 }
 
+- (NSString*)resourcePath {
+#if SWIFT_PACKAGE
+  NSBundle* bundle = SWIFTPM_MODULE_BUNDLE;
+  return [bundle.resourcePath stringByAppendingPathComponent:@"Data"];
+#else
+  NSBundle *bundle = [NSBundle bundleForClass:[self class]];
+  return bundle.resourcePath;
+#endif
+}
+
+- (FIRCLSInternalReport *)createReport {
+  NSString *path = [self.fileManager.activePath stringByAppendingPathComponent:@"pkg_uuid"];
+  FIRCLSInternalReport *report = [[FIRCLSInternalReport alloc] initWithPath:path];
+  self.fileManager.moveItemAtPathResult = [NSNumber numberWithInt:1];
+  return report;
+}
+
 #pragma mark - Tests
 
 - (void)testPrepareReport {
-  FIRCLSInternalReport *report = [[FIRCLSInternalReport alloc] initWithPath:[self packagePath]];
-  self.fileManager.moveItemAtPathResult = [NSNumber numberWithInt:1];
+  FIRCLSInternalReport *report = [self createReport];
 
   XCTAssertNil(self.uploader.fiid);
 
   [self.uploader prepareAndSubmitReport:report
                     dataCollectionToken:FIRCLSDataCollectionToken.validToken
-                               asUrgent:YES
+                               asUrgent:NO
                          withProcessing:YES];
 
   XCTAssertEqual(self.uploader.fiid, TestFIID);
@@ -115,9 +132,64 @@ - (void)testPrepareReport {
       [self.fileManager.moveItemAtPath_destDir containsString:self.fileManager.preparedPath]);
 }
 
+- (void)testPrepareReportOnMainThread {
+  NSString *pathToPlist =
+      [[self resourcePath] stringByAppendingPathComponent:@"GoogleService-Info.plist"];
+  FIROptions *options = [[FIROptions alloc] initWithContentsOfFile:pathToPlist];
+
+  [FIRApp configureWithName:@"__FIRAPP_DEFAULT" options:options];
+  XCTAssertNotNil([FIRApp defaultApp], @"configureWithName must have been initialized");
+
+  FIRInstallations *installations = [FIRInstallations installationsWithApp:[FIRApp defaultApp]];
+  FIRCLSInternalReport *report = [self createReport];
+  [self setupUploaderWithInstallations:installations];
+
+  /*
+   if a report is urgent report will be processed on the Main Thread
+   otherwise, it will be dispatched to a NSOperationQueue (see `FIRCLSExistingReportManager.m:230`)
+
+   This test checks if `prepareAndSubmitReport` finishes in a reasonable time.
+   */
+
+  NSOperationQueue *queue = [NSOperationQueue new];
+
+  // target call will block the main thread, so we need a background thread
+  // that will wait on a semaphore for a timeout
+  dispatch_semaphore_t backgroundWaiter = dispatch_semaphore_create(0);
+  [queue addOperationWithBlock:^{
+    intptr_t result = dispatch_semaphore_wait(backgroundWaiter,
+                                              dispatch_time(DISPATCH_TIME_NOW, 1 * NSEC_PER_SEC));
+    BOOL exitBecauseOfTimeout = result != 0;
+    XCTAssertFalse(exitBecauseOfTimeout, @"Main Thread was blocked for more than 1 second");
+  }];
+
+  // Urgent (on the Main thread)
+  [self.uploader prepareAndSubmitReport:report
+                    dataCollectionToken:FIRCLSDataCollectionToken.validToken
+                               asUrgent:YES
+                         withProcessing:YES];
+  dispatch_semaphore_signal(backgroundWaiter);
+
+  // Not urgent (on a background thread)
+  XCTestExpectation *expectation =
+      [self expectationWithDescription:@"wait for a preparation to complete"];
+
+  [queue addOperationWithBlock:^{
+    [self.uploader prepareAndSubmitReport:report
+                      dataCollectionToken:FIRCLSDataCollectionToken.validToken
+                                 asUrgent:YES
+                           withProcessing:YES];
+    [expectation fulfill];
+  }];
+
+  [self waitForExpectationsWithTimeout:1
+                               handler:^(NSError *_Nullable error) {
+                                 XCTAssertNil(error, @"expectations failed: %@", error);
+                               }];
+}
+
 - (void)test_NilFIID_DoesNotCrash {
-  FIRCLSInternalReport *report = [[FIRCLSInternalReport alloc] initWithPath:[self packagePath]];
-  self.fileManager.moveItemAtPathResult = [NSNumber numberWithInt:1];
+  FIRCLSInternalReport *report = [self createReport];
 
   self.mockInstallations = [[FIRMockInstallations alloc]
       initWithError:[NSError errorWithDomain:@"TestDomain" code:-1 userInfo:nil]];