1 // Copyright (c) 2012 Marshall A. Greenblatt. All rights reserved. 2 // 3 // Redistribution and use in source and binary forms, with or without 4 // modification, are permitted provided that the following conditions are 5 // met: 6 // 7 // * Redistributions of source code must retain the above copyright 8 // notice, this list of conditions and the following disclaimer. 9 // * Redistributions in binary form must reproduce the above 10 // copyright notice, this list of conditions and the following disclaimer 11 // in the documentation and/or other materials provided with the 12 // distribution. 13 // * Neither the name of Google Inc. nor the name Chromium Embedded 14 // Framework nor the names of its contributors may be used to endorse 15 // or promote products derived from this software without specific prior 16 // written permission. 17 // 18 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 19 // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 20 // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 21 // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 22 // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 23 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 24 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 25 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 26 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 27 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 28 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 29 30 #ifndef CEF_INCLUDE_CEF_BASE_H_ 31 #define CEF_INCLUDE_CEF_BASE_H_ 32 #pragma once 33 34 #include "include/base/cef_atomic_ref_count.h" 35 #include "include/base/cef_build.h" 36 #include "include/base/cef_macros.h" 37 38 // Bring in common C++ type definitions used by CEF consumers. 39 #include "include/internal/cef_ptr.h" 40 #include "include/internal/cef_types_wrappers.h" 41 #if defined(OS_WIN) 42 #include "include/internal/cef_win.h" 43 #elif defined(OS_MAC) 44 #include "include/internal/cef_mac.h" 45 #elif defined(OS_LINUX) 46 #include "include/internal/cef_linux.h" 47 #endif 48 49 /// 50 // All ref-counted framework classes must extend this class. 51 /// 52 class CefBaseRefCounted { 53 public: 54 /// 55 // Called to increment the reference count for the object. Should be called 56 // for every new copy of a pointer to a given object. 57 /// 58 virtual void AddRef() const = 0; 59 60 /// 61 // Called to decrement the reference count for the object. Returns true if 62 // the reference count is 0, in which case the object should self-delete. 63 /// 64 virtual bool Release() const = 0; 65 66 /// 67 // Returns true if the reference count is 1. 68 /// 69 virtual bool HasOneRef() const = 0; 70 71 /// 72 // Returns true if the reference count is at least 1. 73 /// 74 virtual bool HasAtLeastOneRef() const = 0; 75 76 protected: ~CefBaseRefCounted()77 virtual ~CefBaseRefCounted() {} 78 }; 79 80 /// 81 // All scoped framework classes must extend this class. 82 /// 83 class CefBaseScoped { 84 public: ~CefBaseScoped()85 virtual ~CefBaseScoped() {} 86 }; 87 88 /// 89 // Class that implements atomic reference counting. 90 /// 91 class CefRefCount { 92 public: 93 CefRefCount() = default; 94 95 CefRefCount(const CefRefCount&) = delete; 96 CefRefCount& operator=(const CefRefCount&) = delete; 97 98 /// 99 // Increment the reference count. 100 /// AddRef()101 void AddRef() const { ref_count_.Increment(); } 102 103 /// 104 // Decrement the reference count. Returns true if the reference count is 0. 105 /// Release()106 bool Release() const { return !ref_count_.Decrement(); } 107 108 /// 109 // Returns true if the reference count is 1. 110 /// HasOneRef()111 bool HasOneRef() const { return ref_count_.IsOne(); } 112 113 /// 114 // Returns true if the reference count is at least 1. 115 /// HasAtLeastOneRef()116 bool HasAtLeastOneRef() const { return !ref_count_.IsZero(); } 117 118 private: 119 mutable base::AtomicRefCount ref_count_{0}; 120 }; 121 122 /// 123 // Macro that provides a reference counting implementation for classes extending 124 // CefBase. 125 /// 126 #define IMPLEMENT_REFCOUNTING(ClassName) \ 127 public: \ 128 void AddRef() const override { ref_count_.AddRef(); } \ 129 bool Release() const override { \ 130 if (ref_count_.Release()) { \ 131 delete static_cast<const ClassName*>(this); \ 132 return true; \ 133 } \ 134 return false; \ 135 } \ 136 bool HasOneRef() const override { return ref_count_.HasOneRef(); } \ 137 bool HasAtLeastOneRef() const override { \ 138 return ref_count_.HasAtLeastOneRef(); \ 139 } \ 140 \ 141 private: \ 142 CefRefCount ref_count_ 143 144 #endif // CEF_INCLUDE_CEF_BASE_H_ 145