Add CFRunLoopObserverCreateWithHandler model and test

Reviewed By: dulmarod

Differential Revision: D8713250

fbshipit-source-id: 7e9761c

infer/models/objc/src/CoreFoundation.c

@@ -7,3 +7,18 @@
 #import <Foundation/Foundation.h>
 
 void CFRelease(CFTypeRef item) { __free_cf(item); }
+
+CFRunLoopObserverRef CFRunLoopObserverCreateWithHandler(
+    CFAllocatorRef allocator,
+    CFOptionFlags activities,
+    Boolean repeats,
+    CFIndex order,
+    void (^block)(CFRunLoopObserverRef observer, CFRunLoopActivity activity)) {
+  // We need to skip allocation for this function since we currently don't
+  // handle object finalizers in objc. This is to avoid false positive memory
+  // leaks when the 'observer' is correctly freed in the block argument.
+
+  // undefined function will get skipped and thus make
+  // CFRunLoopObserverCreateWithHandler return an angelic object
+  return getAngelicObject();
+}

infer/tests/codetoanalyze/objc/errors/Makefile

@@ -27,6 +27,7 @@ SOURCES_DEFAULT = \
   memory_leaks_benchmark/RetainReleaseExampleBucketing.m \
 	memory_leaks_benchmark/CoreVideoExample.m \
 	memory_leaks_benchmark/RetainCycleLength3.m \
+	memory_leaks_benchmark/ReleasedInBlock.m \
   npe/dynamic_dispatch.m \
   npe/Fraction.m \
   npe/NPD_core_foundation.m \

infer/tests/codetoanalyze/objc/errors/memory_leaks_benchmark/ReleasedInBlock.m

@@ -0,0 +1,21 @@
+/*
+ * Copyright (c) 2018-present, Facebook, Inc.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+#import <Foundation/Foundation.h>
+
+void allocAndReleaseInBlock() {
+  void (^callback)(CFRunLoopObserverRef obs, CFRunLoopActivity activity) =
+      ^(CFRunLoopObserverRef obs, CFRunLoopActivity activity) {
+        // We should check if the object is released properly, see
+        // infer/models/objc/src/CoreFoundation.c
+        CFRelease(obs);
+      };
+
+  CFRunLoopObserverRef observer = CFRunLoopObserverCreateWithHandler(
+      NULL, kCFRunLoopBeforeWaiting, NO, UINT_MAX, callback);
+  CFRunLoopAddObserver(CFRunLoopGetMain(), observer, kCFRunLoopCommonModes);
+}