From d44293738059c9d283eef460dafab0b785f84161 Mon Sep 17 00:00:00 2001
From: Martin Trojer <mtrojer@fb.com>
Date: Tue, 3 Jul 2018 00:38:36 -0700
Subject: [PATCH] Add CFRunLoopObserverCreateWithHandler model and test

Reviewed By: dulmarod

Differential Revision: D8713250

fbshipit-source-id: 7e9761c
---
 infer/models/objc/src/CoreFoundation.c        | 15 +++++++++++++
 .../tests/codetoanalyze/objc/errors/Makefile  |  1 +
 .../memory_leaks_benchmark/ReleasedInBlock.m  | 21 +++++++++++++++++++
 3 files changed, 37 insertions(+)
 create mode 100644 infer/tests/codetoanalyze/objc/errors/memory_leaks_benchmark/ReleasedInBlock.m

diff --git a/infer/models/objc/src/CoreFoundation.c b/infer/models/objc/src/CoreFoundation.c
index 693e50c4a..f45fb1829 100644
--- a/infer/models/objc/src/CoreFoundation.c
+++ b/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();
+}
diff --git a/infer/tests/codetoanalyze/objc/errors/Makefile b/infer/tests/codetoanalyze/objc/errors/Makefile
index 32ab04499..9276073ea 100644
--- a/infer/tests/codetoanalyze/objc/errors/Makefile
+++ b/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 \
diff --git a/infer/tests/codetoanalyze/objc/errors/memory_leaks_benchmark/ReleasedInBlock.m b/infer/tests/codetoanalyze/objc/errors/memory_leaks_benchmark/ReleasedInBlock.m
new file mode 100644
index 000000000..b64996da5
--- /dev/null
+++ b/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);
+}