LeakDetector.hpp (6938B)
1 /* 2 * DISTRHO Plugin Framework (DPF) 3 * Copyright (C) 2012-2023 Filipe Coelho <falktx@falktx.com> 4 * 5 * Permission to use, copy, modify, and/or distribute this software for any purpose with 6 * or without fee is hereby granted, provided that the above copyright notice and this 7 * permission notice appear in all copies. 8 * 9 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH REGARD 10 * TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN 11 * NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL 12 * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER 13 * IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN 14 * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 15 */ 16 17 #ifndef DISTRHO_LEAK_DETECTOR_HPP_INCLUDED 18 #define DISTRHO_LEAK_DETECTOR_HPP_INCLUDED 19 20 #include "../DistrhoUtils.hpp" 21 22 START_NAMESPACE_DISTRHO 23 24 // ----------------------------------------------------------------------- 25 // The following code was based from juce-core LeakDetector class 26 27 /** 28 Copyright (C) 2013 Raw Material Software Ltd. 29 30 Permission is granted to use this software under the terms of the ISC license 31 http://www.isc.org/downloads/software-support-policy/isc-license/ 32 33 Permission to use, copy, modify, and/or distribute this software for any 34 purpose with or without fee is hereby granted, provided that the above 35 copyright notice and this permission notice appear in all copies. 36 37 THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH REGARD 38 TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND 39 FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, 40 OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF 41 USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER 42 TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE 43 OF THIS SOFTWARE. 44 */ 45 46 /** A good old-fashioned C macro concatenation helper. 47 This combines two items (which may themselves be macros) into a single string, 48 avoiding the pitfalls of the ## macro operator. 49 */ 50 #define DISTRHO_JOIN_MACRO_HELPER(a, b) a ## b 51 #define DISTRHO_JOIN_MACRO(item1, item2) DISTRHO_JOIN_MACRO_HELPER(item1, item2) 52 53 #if defined(DPF_DEBUG) && !defined(NDEBUG) 54 /** This macro lets you embed a leak-detecting object inside a class.\n 55 To use it, simply declare a DISTRHO_LEAK_DETECTOR(YourClassName) inside a private section 56 of the class declaration. E.g. 57 \code 58 class MyClass 59 { 60 public: 61 MyClass(); 62 void blahBlah(); 63 64 private: 65 DISTRHO_LEAK_DETECTOR(MyClass) 66 }; 67 \endcode 68 */ 69 # define DISTRHO_LEAK_DETECTOR(ClassName) \ 70 friend class DISTRHO_NAMESPACE::LeakedObjectDetector<ClassName>; \ 71 static const char* getLeakedObjectClassName() noexcept { return #ClassName; } \ 72 DISTRHO_NAMESPACE::LeakedObjectDetector<ClassName> DISTRHO_JOIN_MACRO(leakDetector_, ClassName); 73 74 # define DISTRHO_DECLARE_NON_COPYABLE_WITH_LEAK_DETECTOR(ClassName) \ 75 DISTRHO_DECLARE_NON_COPYABLE(ClassName) \ 76 DISTRHO_LEAK_DETECTOR(ClassName) 77 #else 78 /** Don't use leak detection on release builds. */ 79 # define DISTRHO_LEAK_DETECTOR(ClassName) 80 # define DISTRHO_DECLARE_NON_COPYABLE_WITH_LEAK_DETECTOR(ClassName) \ 81 DISTRHO_DECLARE_NON_COPYABLE(ClassName) 82 #endif 83 84 //============================================================================== 85 /** 86 Embedding an instance of this class inside another class can be used as a low-overhead 87 way of detecting leaked instances. 88 89 This class keeps an internal static count of the number of instances that are 90 active, so that when the app is shutdown and the static destructors are called, 91 it can check whether there are any left-over instances that may have been leaked. 92 93 To use it, use the DISTRHO_LEAK_DETECTOR macro as a simple way to put one in your 94 class declaration. 95 */ 96 template<class OwnerClass> 97 class LeakedObjectDetector 98 { 99 public: 100 //============================================================================== 101 LeakedObjectDetector() noexcept { ++(getCounter().numObjects); } 102 LeakedObjectDetector(const LeakedObjectDetector&) noexcept { ++(getCounter().numObjects); } 103 104 ~LeakedObjectDetector() noexcept 105 { 106 if (--(getCounter().numObjects) < 0) 107 { 108 /** If you hit this, then you've managed to delete more instances of this class than you've 109 created.. That indicates that you're deleting some dangling pointers. 110 111 Note that although this assertion will have been triggered during a destructor, it might 112 not be this particular deletion that's at fault - the incorrect one may have happened 113 at an earlier point in the program, and simply not been detected until now. 114 115 Most errors like this are caused by using old-fashioned, non-RAII techniques for 116 your object management. Tut, tut. Always, always use ScopedPointers, OwnedArrays, 117 ReferenceCountedObjects, etc, and avoid the 'delete' operator at all costs! 118 */ 119 d_stderr2("*** Dangling pointer deletion! Class: '%s', Count: %i", getLeakedObjectClassName(), getCounter().numObjects); 120 } 121 } 122 123 private: 124 //============================================================================== 125 class LeakCounter 126 { 127 public: 128 LeakCounter() noexcept 129 : numObjects(0) {} 130 131 ~LeakCounter() noexcept 132 { 133 if (numObjects > 0) 134 { 135 /** If you hit this, then you've leaked one or more objects of the type specified by 136 the 'OwnerClass' template parameter - the name should have been printed by the line above. 137 138 If you're leaking, it's probably because you're using old-fashioned, non-RAII techniques for 139 your object management. Tut, tut. Always, always use ScopedPointers, OwnedArrays, 140 ReferenceCountedObjects, etc, and avoid the 'delete' operator at all costs! 141 */ 142 d_stderr2("*** Leaked objects detected: %i instance(s) of class '%s'", numObjects, getLeakedObjectClassName()); 143 } 144 } 145 146 // this should be an atomic... 147 volatile int numObjects; 148 }; 149 150 static const char* getLeakedObjectClassName() noexcept 151 { 152 return OwnerClass::getLeakedObjectClassName(); 153 } 154 155 static LeakCounter& getCounter() noexcept 156 { 157 static LeakCounter counter; 158 return counter; 159 } 160 }; 161 162 // ----------------------------------------------------------------------- 163 164 END_NAMESPACE_DISTRHO 165 166 #endif // DISTRHO_LEAK_DETECTOR_HPP_INCLUDED