Add new class to handle releasing CFTypeRefs.
The new class wraps any CoreFoundation Type ref and
automatically releases it when it goes out of scope.
Conceptually similar to std::unique_ptr.
Bug: webrtc:7825
Change-Id: Ie49572b9215fcb5b92b2c0c3e3d52b0b3cf01752
Reviewed-on: https://webrtc-review.googlesource.com/3380
Commit-Queue: Kári Helgason <kthelgason@webrtc.org>
Reviewed-by: Magnus Jedvert <magjed@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#20045}diff --git a/sdk/BUILD.gn b/sdk/BUILD.gn
index e660556..0948ce6 100644
--- a/sdk/BUILD.gn
+++ b/sdk/BUILD.gn
@@ -56,6 +56,7 @@
"objc/Framework/Classes/Common/RTCUIApplicationStatusObserver.m",
"objc/Framework/Classes/Common/helpers.h",
"objc/Framework/Classes/Common/helpers.mm",
+ "objc/Framework/Classes/Common/scoped_cftyperef.h",
"objc/Framework/Headers/WebRTC/RTCDispatcher.h",
"objc/Framework/Headers/WebRTC/RTCFieldTrials.h",
"objc/Framework/Headers/WebRTC/RTCLogging.h",
diff --git a/sdk/objc/Framework/Classes/Common/scoped_cftyperef.h b/sdk/objc/Framework/Classes/Common/scoped_cftyperef.h
new file mode 100644
index 0000000..cde7a90
--- /dev/null
+++ b/sdk/objc/Framework/Classes/Common/scoped_cftyperef.h
@@ -0,0 +1,95 @@
+/*
+ * Copyright (c) 2017 The WebRTC project authors. All Rights Reserved.
+ *
+ * Use of this source code is governed by a BSD-style license
+ * that can be found in the LICENSE file in the root of the source
+ * tree. An additional intellectual property rights grant can be found
+ * in the file PATENTS. All contributing project authors may
+ * be found in the AUTHORS file in the root of the source tree.
+ *
+ */
+
+#ifndef WEBRTC_SDK_OBJC_FRAMEWORK_CLASSES_COMMON_SCOPED_CFTYPEREF_H_
+#define WEBRTC_SDK_OBJC_FRAMEWORK_CLASSES_COMMON_SCOPED_CFTYPEREF_H_
+
+#include <CoreFoundation/CoreFoundation.h>
+namespace rtc {
+
+template <typename T>
+class ScopedCFTypeRef {
+ public:
+ // RETAIN: ScopedCFTypeRef should retain the object when it takes
+ // ownership.
+ // ASSUME: Assume the object already has already been retained.
+ // ScopedCFTypeRef takes over ownership.
+ enum class RetainPolicy { RETAIN, ASSUME };
+
+ ScopedCFTypeRef() : ptr_(nullptr) {}
+ explicit ScopedCFTypeRef(T ptr) : ptr_(ptr) {}
+ ScopedCFTypeRef(T ptr, RetainPolicy policy) : ScopedCFTypeRef(ptr) {
+ if (ptr_ && policy == RetainPolicy::RETAIN)
+ CFRetain(ptr_);
+ }
+
+ ~ScopedCFTypeRef() {
+ if (ptr_) {
+ CFRelease(ptr_);
+ }
+ }
+
+ T get() const { return ptr_; }
+ T operator->() const { return ptr_; }
+ explicit operator bool() const { return ptr_; }
+
+ bool operator!() const { return !ptr_; }
+
+ ScopedCFTypeRef& operator=(const T& rhs) {
+ if (ptr_)
+ CFRelease(ptr_);
+ ptr_ = rhs;
+ return *this;
+ }
+
+ ScopedCFTypeRef& operator=(const ScopedCFTypeRef<T>& rhs) {
+ reset(rhs.get(), RetainPolicy::RETAIN);
+ return *this;
+ }
+
+ // This is intended to take ownership of objects that are
+ // created by pass-by-pointer initializers.
+ T* InitializeInto() {
+ RTC_DCHECK(!ptr_);
+ return &ptr_;
+ }
+
+ void reset(T ptr, RetainPolicy policy = RetainPolicy::ASSUME) {
+ if (ptr && policy == RetainPolicy::RETAIN)
+ CFRetain(ptr);
+ if (ptr_)
+ CFRelease(ptr_);
+ ptr_ = ptr;
+ }
+
+ T release() {
+ T temp = ptr_;
+ ptr_ = nullptr;
+ return temp;
+ }
+
+ private:
+ T ptr_;
+};
+
+template <typename T>
+static ScopedCFTypeRef<T> AdoptCF(T cftype) {
+ return ScopedCFTypeRef<T>(cftype, RetainPolicy::RETAIN);
+}
+
+template <typename T>
+static ScopedCFTypeRef<T> ScopedCF(T cftype) {
+ return ScopedCFTypeRef<T>(cftype);
+}
+
+} // namespace rtc
+
+#endif // WEBRTC_SDK_OBJC_FRAMEWORK_CLASSES_COMMON_SCOPED_CFTYPEREF_H_
