third_party/WebKit/Source/wtf/InstanceCounter.cpp

   1 /*
   2  * Copyright (C) 2013 Google Inc. All rights reserved.
   3  *
   4  * Redistribution and use in source and binary forms, with or without
   5  * modification, are permitted provided that the following conditions
   6  * are met:
   7  *
   8  * 1.  Redistributions of source code must retain the above copyright
   9  *     notice, this list of conditions and the following disclaimer.
  10  * 2.  Redistributions in binary form must reproduce the above copyright
  11  *     notice, this list of conditions and the following disclaimer in the
  12  *     documentation and/or other materials provided with the distribution.
  13  *
  14  * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
  15  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
  16  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  17  * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
  18  * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
  19  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  20  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
  21  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  22  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  23  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  24  */
  25
  26 #include "config.h"
  27 #include "InstanceCounter.h"
  28
  29 #include "wtf/HashMap.h"
  30 #include "wtf/StdLibExtras.h"
  31 #include "wtf/ThreadingPrimitives.h"
  32 #include "wtf/text/StringBuilder.h"
  33 #include "wtf/text/StringHash.h"
  34 #include "wtf/text/WTFString.h"
  35
  36 namespace WTF {
  37
  38 #if ENABLE(INSTANCE_COUNTER) || ENABLE(GC_PROFILING) || ENABLE(DETAILED_MEMORY_INFRA)
  39
  40 #if COMPILER(CLANG)
  41 const size_t extractNameFunctionPrefixLength = sizeof("const char *WTF::extractNameFunction() [T = ") - 1;
  42 const size_t extractNameFunctionPostfixLength = sizeof("]") - 1;
  43 #elif COMPILER(GCC)
  44 const size_t extractNameFunctionPrefixLength = sizeof("const char* WTF::extractNameFunction() [with T = ") - 1;
  45 const size_t extractNameFunctionPostfixLength = sizeof("]") - 1;
  46 #elif COMPILER(MSVC)
  47 const size_t extractNameFunctionPrefixLength = sizeof("const char *__cdecl WTF::extractNameFunction<class ") - 1;
  48 const size_t extractNameFunctionPostfixLength = sizeof(">(void)") - 1;
  49 #else
  50 #warning "Extracting typename is supported only in compiler GCC, CLANG and MSVC at this moment"
  51 #endif
  52
  53 // This function is used to stringify a typename T without using RTTI.
  54 // The result of extractNameFunction<T>() is given as |funcName|. |extractTypeNameFromFunctionName| then extracts a typename string from |funcName|.
  55 String extractTypeNameFromFunctionName(const char* funcName)
  56 {
  57 #if COMPILER(CLANG) || COMPILER(GCC) || COMPILER(MSVC)
  58     size_t funcNameLength = strlen(funcName);
  59     ASSERT(funcNameLength > extractNameFunctionPrefixLength + extractNameFunctionPostfixLength);
  60
  61     const char* funcNameWithoutPrefix = funcName + extractNameFunctionPrefixLength;
  62     return String(funcNameWithoutPrefix, funcNameLength - extractNameFunctionPrefixLength - extractNameFunctionPostfixLength);
  63 #else
  64     return String("unknown");
  65 #endif
  66 }
  67
  68 class InstanceCounter {
  69 public:
  70     void incrementInstanceCount(const String& instanceName, void* ptr);
  71     void decrementInstanceCount(const String& instanceName, void* ptr);
  72     String dump();
  73
  74     static InstanceCounter* instance()
  75     {
  76         DEFINE_STATIC_LOCAL(InstanceCounter, self, ());
  77         return &self;
  78     }
  79
  80 private:
  81     InstanceCounter() { }
  82
  83     Mutex m_mutex;
  84     HashMap<String, int> m_counterMap;
  85 };
  86
  87 void incrementInstanceCount(const char* extractNameFunctionName, void* ptr)
  88 {
  89     String instanceName = extractTypeNameFromFunctionName(extractNameFunctionName);
  90     InstanceCounter::instance()->incrementInstanceCount(instanceName, ptr);
  91 }
  92
  93 void decrementInstanceCount(const char* extractNameFunctionName, void* ptr)
  94 {
  95     String instanceName = extractTypeNameFromFunctionName(extractNameFunctionName);
  96     InstanceCounter::instance()->decrementInstanceCount(instanceName, ptr);
  97 }
  98
  99 String dumpRefCountedInstanceCounts()
 100 {
 101     return InstanceCounter::instance()->dump();
 102 }
 103
 104 void InstanceCounter::incrementInstanceCount(const String& instanceName, void* ptr)
 105 {
 106     MutexLocker locker(m_mutex);
 107     HashMap<String, int>::AddResult result = m_counterMap.add(instanceName, 1);
 108     if (!result.isNewEntry)
 109         ++(result.storedValue->value);
 110 }
 111
 112 void InstanceCounter::decrementInstanceCount(const String& instanceName, void* ptr)
 113 {
 114     MutexLocker locker(m_mutex);
 115     HashMap<String, int>::iterator it = m_counterMap.find(instanceName);
 116     ASSERT(it != m_counterMap.end());
 117
 118     --(it->value);
 119     if (!it->value)
 120         m_counterMap.remove(it);
 121 }
 122
 123 String InstanceCounter::dump()
 124 {
 125     MutexLocker locker(m_mutex);
 126
 127     StringBuilder builder;
 128
 129     builder.append('{');
 130     HashMap<String, int>::iterator it = m_counterMap.begin();
 131     HashMap<String, int>::iterator itEnd = m_counterMap.end();
 132     for (; it != itEnd; ++it) {
 133         if (it != m_counterMap.begin())
 134             builder.append(',');
 135         builder.append('"');
 136         builder.append(it->key);
 137         builder.appendLiteral("\": ");
 138         builder.appendNumber(it->value);
 139     }
 140     builder.append('}');
 141
 142     return builder.toString();
 143 }
 144
 145 #else
 146
 147 String dumpRefCountedInstanceCounts()
 148 {
 149     return String("{}");
 150 }
 151
 152 #endif // ENABLE(INSTANCE_COUNTER) || ENABLE(GC_PROFILING)
 153
 154 } // namespace WTF