From 2239cee23e914b974b458699d52733d7dd3116a6 Mon Sep 17 00:00:00 2001 From: tsepez Date: Mon, 17 Oct 2016 11:20:01 -0700 Subject: Rename CFX_CountRef to CFX_SharedCopyOnWrite Avoid confusing this class with other ref-counted objects. Review-Url: https://codereview.chromium.org/2426673002 --- core/fxcrt/cfx_count_ref.h | 81 -------------- core/fxcrt/cfx_count_ref_unittest.cpp | 129 ----------------------- core/fxcrt/cfx_shared_copy_on_write.h | 84 +++++++++++++++ core/fxcrt/cfx_shared_copy_on_write_unittest.cpp | 129 +++++++++++++++++++++++ 4 files changed, 213 insertions(+), 210 deletions(-) delete mode 100644 core/fxcrt/cfx_count_ref.h delete mode 100644 core/fxcrt/cfx_count_ref_unittest.cpp create mode 100644 core/fxcrt/cfx_shared_copy_on_write.h create mode 100644 core/fxcrt/cfx_shared_copy_on_write_unittest.cpp (limited to 'core/fxcrt') diff --git a/core/fxcrt/cfx_count_ref.h b/core/fxcrt/cfx_count_ref.h deleted file mode 100644 index 3b9ccff8fe..0000000000 --- a/core/fxcrt/cfx_count_ref.h +++ /dev/null @@ -1,81 +0,0 @@ -// Copyright 2016 PDFium Authors. All rights reserved. -// Use of this source code is governed by a BSD-style license that can be -// found in the LICENSE file. - -// Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com - -#ifndef CORE_FXCRT_CFX_COUNT_REF_H_ -#define CORE_FXCRT_CFX_COUNT_REF_H_ - -#include "core/fxcrt/cfx_retain_ptr.h" -#include "core/fxcrt/fx_system.h" - -// A shared object with Copy on Write semantics that makes it appear as -// if each one were independent. -template -class CFX_CountRef { - public: - CFX_CountRef() {} - CFX_CountRef(const CFX_CountRef& other) : m_pObject(other.m_pObject) {} - ~CFX_CountRef() {} - - template - ObjClass* Emplace(Args... params) { - m_pObject.Reset(new CountedObj(params...)); - return m_pObject.Get(); - } - - CFX_CountRef& operator=(const CFX_CountRef& that) { - if (*this != that) - m_pObject = that.m_pObject; - return *this; - } - - void SetNull() { m_pObject.Reset(); } - const ObjClass* GetObject() const { return m_pObject.Get(); } - - template - ObjClass* GetPrivateCopy(Args... params) { - if (!m_pObject) - return Emplace(params...); - if (!m_pObject->HasOneRef()) - m_pObject.Reset(new CountedObj(*m_pObject)); - return m_pObject.Get(); - } - - bool operator==(const CFX_CountRef& that) const { - return m_pObject == that.m_pObject; - } - bool operator!=(const CFX_CountRef& that) const { return !(*this == that); } - explicit operator bool() const { return !!m_pObject; } - - private: - class CountedObj : public ObjClass { - public: - template - CountedObj(Args... params) : ObjClass(params...), m_RefCount(0) {} - - CountedObj(const CountedObj& src) : ObjClass(src), m_RefCount(0) {} - ~CountedObj() { m_RefCount = 0; } - - bool HasOneRef() const { return m_RefCount == 1; } - void Retain() { m_RefCount++; } - void Release() { - ASSERT(m_RefCount); - if (--m_RefCount == 0) - delete this; - } - - private: - // To ensure ref counts do not overflow, consider the worst possible case: - // the entire address space contains nothing but pointers to this object. - // Since the count increments with each new pointer, the largest value is - // the number of pointers that can fit into the address space. The size of - // the address space itself is a good upper bound on it. - intptr_t m_RefCount; - }; - - CFX_RetainPtr m_pObject; -}; - -#endif // CORE_FXCRT_CFX_COUNT_REF_H_ diff --git a/core/fxcrt/cfx_count_ref_unittest.cpp b/core/fxcrt/cfx_count_ref_unittest.cpp deleted file mode 100644 index 6ab56327d3..0000000000 --- a/core/fxcrt/cfx_count_ref_unittest.cpp +++ /dev/null @@ -1,129 +0,0 @@ -// Copyright 2016 PDFium Authors. All rights reserved. -// Use of this source code is governed by a BSD-style license that can be -// found in the LICENSE file. - -#include "core/fxcrt/cfx_count_ref.h" - -#include -#include - -#include "testing/fx_string_testhelpers.h" -#include "testing/gtest/include/gtest/gtest.h" - -namespace { - -class Observer { - public: - void OnConstruct(const std::string& name) { construction_counts_[name]++; } - void OnDestruct(const std::string& name) { destruction_counts_[name]++; } - int GetConstructionCount(const std::string& name) { - return construction_counts_[name]; - } - int GetDestructionCount(const std::string& name) { - return destruction_counts_[name]; - } - - private: - std::map construction_counts_; - std::map destruction_counts_; -}; - -class Object { - public: - Object(Observer* observer, const std::string& name) - : name_(name), observer_(observer) { - observer->OnConstruct(name_); - } - Object(const Object& that) : name_(that.name_), observer_(that.observer_) { - observer_->OnConstruct(name_); - } - ~Object() { observer_->OnDestruct(name_); } - - private: - std::string name_; - Observer* observer_; -}; - -} // namespace - -TEST(fxcrt, CountRefNull) { - Observer observer; - { - CFX_CountRef ptr; - EXPECT_EQ(nullptr, ptr.GetObject()); - } -} - -TEST(fxcrt, CountRefCopy) { - Observer observer; - { - CFX_CountRef ptr1; - ptr1.Emplace(&observer, std::string("one")); - { - CFX_CountRef ptr2 = ptr1; - EXPECT_EQ(1, observer.GetConstructionCount("one")); - EXPECT_EQ(0, observer.GetDestructionCount("one")); - } - { - CFX_CountRef ptr3(ptr1); - EXPECT_EQ(1, observer.GetConstructionCount("one")); - EXPECT_EQ(0, observer.GetDestructionCount("one")); - } - EXPECT_EQ(1, observer.GetConstructionCount("one")); - EXPECT_EQ(0, observer.GetDestructionCount("one")); - } - EXPECT_EQ(1, observer.GetDestructionCount("one")); -} - -TEST(fxcrt, CountRefAssignOverOld) { - Observer observer; - { - CFX_CountRef ptr1; - ptr1.Emplace(&observer, std::string("one")); - ptr1.Emplace(&observer, std::string("two")); - EXPECT_EQ(1, observer.GetConstructionCount("one")); - EXPECT_EQ(1, observer.GetConstructionCount("two")); - EXPECT_EQ(1, observer.GetDestructionCount("one")); - EXPECT_EQ(0, observer.GetDestructionCount("two")); - } - EXPECT_EQ(1, observer.GetDestructionCount("two")); -} - -TEST(fxcrt, CountRefAssignOverRetained) { - Observer observer; - { - CFX_CountRef ptr1; - ptr1.Emplace(&observer, std::string("one")); - CFX_CountRef ptr2(ptr1); - ptr1.Emplace(&observer, std::string("two")); - EXPECT_EQ(1, observer.GetConstructionCount("one")); - EXPECT_EQ(1, observer.GetConstructionCount("two")); - EXPECT_EQ(0, observer.GetDestructionCount("one")); - EXPECT_EQ(0, observer.GetDestructionCount("two")); - } - EXPECT_EQ(1, observer.GetDestructionCount("one")); - EXPECT_EQ(1, observer.GetDestructionCount("two")); -} - -TEST(fxcrt, CountRefGetModify) { - Observer observer; - { - CFX_CountRef ptr; - EXPECT_NE(nullptr, ptr.GetPrivateCopy(&observer, std::string("one"))); - EXPECT_EQ(1, observer.GetConstructionCount("one")); - EXPECT_EQ(0, observer.GetDestructionCount("one")); - - EXPECT_NE(nullptr, ptr.GetPrivateCopy(&observer, std::string("one"))); - EXPECT_EQ(1, observer.GetConstructionCount("one")); - EXPECT_EQ(0, observer.GetDestructionCount("one")); - { - CFX_CountRef other(ptr); - EXPECT_NE(nullptr, ptr.GetPrivateCopy(&observer, std::string("one"))); - EXPECT_EQ(2, observer.GetConstructionCount("one")); - EXPECT_EQ(0, observer.GetDestructionCount("one")); - } - EXPECT_EQ(2, observer.GetConstructionCount("one")); - EXPECT_EQ(1, observer.GetDestructionCount("one")); - } - EXPECT_EQ(2, observer.GetDestructionCount("one")); -} diff --git a/core/fxcrt/cfx_shared_copy_on_write.h b/core/fxcrt/cfx_shared_copy_on_write.h new file mode 100644 index 0000000000..cd6cf6adc5 --- /dev/null +++ b/core/fxcrt/cfx_shared_copy_on_write.h @@ -0,0 +1,84 @@ +// Copyright 2016 PDFium Authors. All rights reserved. +// Use of this source code is governed by a BSD-style license that can be +// found in the LICENSE file. + +// Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com + +#ifndef CORE_FXCRT_CFX_SHARED_COPY_ON_WRITE_H_ +#define CORE_FXCRT_CFX_SHARED_COPY_ON_WRITE_H_ + +#include "core/fxcrt/cfx_retain_ptr.h" +#include "core/fxcrt/fx_system.h" + +// A shared object with Copy on Write semantics that makes it appear as +// if each one were independent. +template +class CFX_SharedCopyOnWrite { + public: + CFX_SharedCopyOnWrite() {} + CFX_SharedCopyOnWrite(const CFX_SharedCopyOnWrite& other) + : m_pObject(other.m_pObject) {} + ~CFX_SharedCopyOnWrite() {} + + template + ObjClass* Emplace(Args... params) { + m_pObject.Reset(new CountedObj(params...)); + return m_pObject.Get(); + } + + CFX_SharedCopyOnWrite& operator=(const CFX_SharedCopyOnWrite& that) { + if (*this != that) + m_pObject = that.m_pObject; + return *this; + } + + void SetNull() { m_pObject.Reset(); } + const ObjClass* GetObject() const { return m_pObject.Get(); } + + template + ObjClass* GetPrivateCopy(Args... params) { + if (!m_pObject) + return Emplace(params...); + if (!m_pObject->HasOneRef()) + m_pObject.Reset(new CountedObj(*m_pObject)); + return m_pObject.Get(); + } + + bool operator==(const CFX_SharedCopyOnWrite& that) const { + return m_pObject == that.m_pObject; + } + bool operator!=(const CFX_SharedCopyOnWrite& that) const { + return !(*this == that); + } + explicit operator bool() const { return !!m_pObject; } + + private: + class CountedObj : public ObjClass { + public: + template + CountedObj(Args... params) : ObjClass(params...), m_RefCount(0) {} + + CountedObj(const CountedObj& src) : ObjClass(src), m_RefCount(0) {} + ~CountedObj() { m_RefCount = 0; } + + bool HasOneRef() const { return m_RefCount == 1; } + void Retain() { m_RefCount++; } + void Release() { + ASSERT(m_RefCount); + if (--m_RefCount == 0) + delete this; + } + + private: + // To ensure ref counts do not overflow, consider the worst possible case: + // the entire address space contains nothing but pointers to this object. + // Since the count increments with each new pointer, the largest value is + // the number of pointers that can fit into the address space. The size of + // the address space itself is a good upper bound on it. + intptr_t m_RefCount; + }; + + CFX_RetainPtr m_pObject; +}; + +#endif // CORE_FXCRT_CFX_SHARED_COPY_ON_WRITE_H_ diff --git a/core/fxcrt/cfx_shared_copy_on_write_unittest.cpp b/core/fxcrt/cfx_shared_copy_on_write_unittest.cpp new file mode 100644 index 0000000000..b0205d899b --- /dev/null +++ b/core/fxcrt/cfx_shared_copy_on_write_unittest.cpp @@ -0,0 +1,129 @@ +// Copyright 2016 PDFium Authors. All rights reserved. +// Use of this source code is governed by a BSD-style license that can be +// found in the LICENSE file. + +#include "core/fxcrt/cfx_shared_copy_on_write.h" + +#include +#include + +#include "testing/fx_string_testhelpers.h" +#include "testing/gtest/include/gtest/gtest.h" + +namespace { + +class Observer { + public: + void OnConstruct(const std::string& name) { construction_counts_[name]++; } + void OnDestruct(const std::string& name) { destruction_counts_[name]++; } + int GetConstructionCount(const std::string& name) { + return construction_counts_[name]; + } + int GetDestructionCount(const std::string& name) { + return destruction_counts_[name]; + } + + private: + std::map construction_counts_; + std::map destruction_counts_; +}; + +class Object { + public: + Object(Observer* observer, const std::string& name) + : name_(name), observer_(observer) { + observer->OnConstruct(name_); + } + Object(const Object& that) : name_(that.name_), observer_(that.observer_) { + observer_->OnConstruct(name_); + } + ~Object() { observer_->OnDestruct(name_); } + + private: + std::string name_; + Observer* observer_; +}; + +} // namespace + +TEST(fxcrt, SharedCopyOnWriteNull) { + Observer observer; + { + CFX_SharedCopyOnWrite ptr; + EXPECT_EQ(nullptr, ptr.GetObject()); + } +} + +TEST(fxcrt, SharedCopyOnWriteCopy) { + Observer observer; + { + CFX_SharedCopyOnWrite ptr1; + ptr1.Emplace(&observer, std::string("one")); + { + CFX_SharedCopyOnWrite ptr2 = ptr1; + EXPECT_EQ(1, observer.GetConstructionCount("one")); + EXPECT_EQ(0, observer.GetDestructionCount("one")); + } + { + CFX_SharedCopyOnWrite ptr3(ptr1); + EXPECT_EQ(1, observer.GetConstructionCount("one")); + EXPECT_EQ(0, observer.GetDestructionCount("one")); + } + EXPECT_EQ(1, observer.GetConstructionCount("one")); + EXPECT_EQ(0, observer.GetDestructionCount("one")); + } + EXPECT_EQ(1, observer.GetDestructionCount("one")); +} + +TEST(fxcrt, SharedCopyOnWriteAssignOverOld) { + Observer observer; + { + CFX_SharedCopyOnWrite ptr1; + ptr1.Emplace(&observer, std::string("one")); + ptr1.Emplace(&observer, std::string("two")); + EXPECT_EQ(1, observer.GetConstructionCount("one")); + EXPECT_EQ(1, observer.GetConstructionCount("two")); + EXPECT_EQ(1, observer.GetDestructionCount("one")); + EXPECT_EQ(0, observer.GetDestructionCount("two")); + } + EXPECT_EQ(1, observer.GetDestructionCount("two")); +} + +TEST(fxcrt, SharedCopyOnWriteAssignOverRetained) { + Observer observer; + { + CFX_SharedCopyOnWrite ptr1; + ptr1.Emplace(&observer, std::string("one")); + CFX_SharedCopyOnWrite ptr2(ptr1); + ptr1.Emplace(&observer, std::string("two")); + EXPECT_EQ(1, observer.GetConstructionCount("one")); + EXPECT_EQ(1, observer.GetConstructionCount("two")); + EXPECT_EQ(0, observer.GetDestructionCount("one")); + EXPECT_EQ(0, observer.GetDestructionCount("two")); + } + EXPECT_EQ(1, observer.GetDestructionCount("one")); + EXPECT_EQ(1, observer.GetDestructionCount("two")); +} + +TEST(fxcrt, SharedCopyOnWriteGetModify) { + Observer observer; + { + CFX_SharedCopyOnWrite ptr; + EXPECT_NE(nullptr, ptr.GetPrivateCopy(&observer, std::string("one"))); + EXPECT_EQ(1, observer.GetConstructionCount("one")); + EXPECT_EQ(0, observer.GetDestructionCount("one")); + + EXPECT_NE(nullptr, ptr.GetPrivateCopy(&observer, std::string("one"))); + EXPECT_EQ(1, observer.GetConstructionCount("one")); + EXPECT_EQ(0, observer.GetDestructionCount("one")); + { + CFX_SharedCopyOnWrite other(ptr); + EXPECT_NE(nullptr, ptr.GetPrivateCopy(&observer, std::string("one"))); + EXPECT_EQ(2, observer.GetConstructionCount("one")); + EXPECT_EQ(0, observer.GetDestructionCount("one")); + } + EXPECT_EQ(2, observer.GetConstructionCount("one")); + EXPECT_EQ(1, observer.GetDestructionCount("one")); + } + EXPECT_EQ(2, observer.GetDestructionCount("one")); +} -- cgit v1.2.3