diff --git a/rtc_base/copy_on_write_buffer.cc b/rtc_base/copy_on_write_buffer.cc index 73182a12b1..f3cc710f85 100644 --- a/rtc_base/copy_on_write_buffer.cc +++ b/rtc_base/copy_on_write_buffer.cc @@ -32,16 +32,15 @@ CopyOnWriteBuffer::CopyOnWriteBuffer(const std::string& s) : CopyOnWriteBuffer(s.data(), s.length()) {} CopyOnWriteBuffer::CopyOnWriteBuffer(size_t size) - : buffer_(size > 0 ? new RefCountedObject(size) : nullptr), + : buffer_(size > 0 ? new RefCountedBuffer(size) : nullptr), offset_(0), size_(size) { RTC_DCHECK(IsConsistent()); } CopyOnWriteBuffer::CopyOnWriteBuffer(size_t size, size_t capacity) - : buffer_(size > 0 || capacity > 0 - ? new RefCountedObject(size, capacity) - : nullptr), + : buffer_(size > 0 || capacity > 0 ? new RefCountedBuffer(size, capacity) + : nullptr), offset_(0), size_(size) { RTC_DCHECK(IsConsistent()); @@ -61,7 +60,7 @@ void CopyOnWriteBuffer::SetSize(size_t size) { RTC_DCHECK(IsConsistent()); if (!buffer_) { if (size > 0) { - buffer_ = new RefCountedObject(size); + buffer_ = new RefCountedBuffer(size); offset_ = 0; size_ = size; } @@ -84,7 +83,7 @@ void CopyOnWriteBuffer::EnsureCapacity(size_t new_capacity) { RTC_DCHECK(IsConsistent()); if (!buffer_) { if (new_capacity > 0) { - buffer_ = new RefCountedObject(0, new_capacity); + buffer_ = new RefCountedBuffer(0, new_capacity); offset_ = 0; size_ = 0; } @@ -105,7 +104,7 @@ void CopyOnWriteBuffer::Clear() { if (buffer_->HasOneRef()) { buffer_->Clear(); } else { - buffer_ = new RefCountedObject(0, capacity()); + buffer_ = new RefCountedBuffer(0, capacity()); } offset_ = 0; size_ = 0; @@ -117,8 +116,8 @@ void CopyOnWriteBuffer::UnshareAndEnsureCapacity(size_t new_capacity) { return; } - buffer_ = new RefCountedObject(buffer_->data() + offset_, size_, - new_capacity); + buffer_ = + new RefCountedBuffer(buffer_->data() + offset_, size_, new_capacity); offset_ = 0; RTC_DCHECK(IsConsistent()); } diff --git a/rtc_base/copy_on_write_buffer.h b/rtc_base/copy_on_write_buffer.h index 9ec72ee523..526cbe5c5c 100644 --- a/rtc_base/copy_on_write_buffer.h +++ b/rtc_base/copy_on_write_buffer.h @@ -159,9 +159,9 @@ class RTC_EXPORT CopyOnWriteBuffer { void SetData(const T* data, size_t size) { RTC_DCHECK(IsConsistent()); if (!buffer_) { - buffer_ = size > 0 ? new RefCountedObject(data, size) : nullptr; + buffer_ = size > 0 ? new RefCountedBuffer(data, size) : nullptr; } else if (!buffer_->HasOneRef()) { - buffer_ = new RefCountedObject(data, size, capacity()); + buffer_ = new RefCountedBuffer(data, size, capacity()); } else { buffer_->SetData(data, size); } @@ -196,7 +196,7 @@ class RTC_EXPORT CopyOnWriteBuffer { void AppendData(const T* data, size_t size) { RTC_DCHECK(IsConsistent()); if (!buffer_) { - buffer_ = new RefCountedObject(data, size); + buffer_ = new RefCountedBuffer(data, size); offset_ = 0; size_ = size; RTC_DCHECK(IsConsistent()); @@ -242,7 +242,7 @@ class RTC_EXPORT CopyOnWriteBuffer { // Swaps two buffers. friend void swap(CopyOnWriteBuffer& a, CopyOnWriteBuffer& b) { - std::swap(a.buffer_, b.buffer_); + a.buffer_.swap(b.buffer_); std::swap(a.offset_, b.offset_); std::swap(a.size_, b.size_); } @@ -257,6 +257,7 @@ class RTC_EXPORT CopyOnWriteBuffer { } private: + using RefCountedBuffer = FinalRefCountedObject; // Create a copy of the underlying data if it is referenced from other Buffer // objects or there is not enough capacity. void UnshareAndEnsureCapacity(size_t new_capacity); @@ -272,7 +273,7 @@ class RTC_EXPORT CopyOnWriteBuffer { } // buffer_ is either null, or points to an rtc::Buffer with capacity > 0. - scoped_refptr> buffer_; + scoped_refptr buffer_; // This buffer may represent a slice of a original data. size_t offset_; // Offset of a current slice in the original data in buffer_. // Should be 0 if the buffer_ is empty. diff --git a/rtc_base/ref_counted_object.h b/rtc_base/ref_counted_object.h index ce18379d50..e86a1fba0d 100644 --- a/rtc_base/ref_counted_object.h +++ b/rtc_base/ref_counted_object.h @@ -59,6 +59,37 @@ class RefCountedObject : public T { RTC_DISALLOW_COPY_AND_ASSIGN(RefCountedObject); }; +template +class FinalRefCountedObject final : public T { + public: + using T::T; + // Until c++17 compilers are allowed not to inherit the default constructor, + // and msvc doesn't. Thus the default constructor is forwarded explicitly. + FinalRefCountedObject() = default; + FinalRefCountedObject(const FinalRefCountedObject&) = delete; + FinalRefCountedObject& operator=(const FinalRefCountedObject&) = delete; + + void AddRef() const { ref_count_.IncRef(); } + void Release() const { + if (ref_count_.DecRef() == RefCountReleaseStatus::kDroppedLastRef) { + delete this; + } + } + bool HasOneRef() const { return ref_count_.HasOneRef(); } + + private: + ~FinalRefCountedObject() = default; + + // gcc v7.1 requires default contructors for members of + // `FinalRefCountedObject` to be able to use inherited constructors. + // TODO(danilchap): Replace with simpler braced initialization when + // bot support for that version of gcc is dropped. + class ZeroBasedRefCounter : public webrtc::webrtc_impl::RefCounter { + public: + ZeroBasedRefCounter() : RefCounter(0) {} + } mutable ref_count_; +}; + } // namespace rtc #endif // RTC_BASE_REF_COUNTED_OBJECT_H_ diff --git a/rtc_base/ref_counted_object_unittest.cc b/rtc_base/ref_counted_object_unittest.cc index eacf731782..05380b7ca9 100644 --- a/rtc_base/ref_counted_object_unittest.cc +++ b/rtc_base/ref_counted_object_unittest.cc @@ -12,6 +12,7 @@ #include #include +#include #include #include "api/scoped_refptr.h" @@ -95,4 +96,19 @@ TEST(RefCountedObject, SupportMixedTypesInCtor) { EXPECT_EQ(c, ref->c_); } +TEST(FinalRefCountedObject, CanWrapIntoScopedRefptr) { + using WrappedTyped = FinalRefCountedObject; + static_assert(!std::is_polymorphic::value, ""); + scoped_refptr ref(new WrappedTyped()); + EXPECT_TRUE(ref.get()); + EXPECT_TRUE(ref->HasOneRef()); + // Test reference counter is updated on some simple operations. + scoped_refptr ref2 = ref; + EXPECT_FALSE(ref->HasOneRef()); + EXPECT_FALSE(ref2->HasOneRef()); + + ref = nullptr; + EXPECT_TRUE(ref2->HasOneRef()); +} + } // namespace rtc