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我有一個非常糟糕的內存泄漏，我試圖修復，但不知何故，我無法刪除對象，而沒有觸發這個斷言。調試斷言失敗... _BLOCK_TYPE_IS_VALID（pHead-> nBlockUse）
我已經通過Google搜索了一個解決方案，並閱讀了有關此錯誤的stackoverflow問題，但我仍然無法找到答案！
可能的原因，根據我的研究，出現此錯誤：
1.刪除對象不止一個
2.影子複製
3.創建和刪除是從外部的dll加載的對象
4.創建對象不存儲指針
但是：
1.我檢查了代碼，沒能找到雙缺失
2.我用一個拷貝構造函數來複制對象
3.錯誤關聯類是建立（與MS Visual Studio）到一個單獨的庫，但不是一個DLL。並且與此錯誤相關的所有類都位於同一個庫中。
4.我檢查了代碼，它似乎不是問題
如果有人能夠發現下面的代碼中的錯誤，這將是非常好的，我感謝每一個提示，指出我的解決方案問題。
編輯：
我忘了提及MessageSystem的sendThreadMain（請參閱下面的代碼）中相同的刪除問題。如果我在那裏刪除消息，它會在代碼中的其他地方導致意外的錯誤。可能只是錯誤的數據傳輸......但我不知道。
此代碼在Windows和Linux上運行！
下面是相關的部分代碼錯誤：
消息
class Message
{
public:
Message (char type, unsigned char id, unsigned short size)
{
mType = type;
mId = id;
mSize= size;
}
Message(const Message &o)
{
mType = o.mType;
mId = o.mId;
mSize = o.mSize;
}
char getType() const {return mType;};
unsigned char getId() const {return mId;};
unsigned short getSize() const {return mSize;};
protected:
char mType;
unsigned char mId;
unsigned short mSize;
};
class JoinMessage : public Message
{
public:
JoinMessage() : Message ('j', 0, sizeof (JoinMessage))
{
team = TEAM_SPECTATOR;
}
JoinMessage (unsigned char id) : Message ('j', id, sizeof (JoinMessage)){}
JoinMessage (const JoinMessage &o) : Message (o)
{
team = o.team;
setName(o.getName());
}
void setName(std::string newName)
{
if (newName.length() > MAX_PLAYER_NAME_LENGHT)
newName = newName.substr(0, MAX_PLAYER_NAME_LENGHT);
memset(name, 0, MAX_PLAYER_NAME_LENGHT);
for(unsigned int i = 0; i < newName.length(); i++)
name[i] = newName[i];
}
std::string getName() const
{
std::string stringToReturn;
for(unsigned int i = 0; i < MAX_PLAYER_NAME_LENGHT; i++)
{
if (name[i])
stringToReturn.push_back(name[i]);
else
break;
}
return stringToReturn;
}
TeamIdentifier team;
private:
unsigned char name[MAX_PLAYER_NAME_LENGHT];
};
// there are a lot other messages
的MessageQueue
MessageQueue::~MessageQueue()
{
boost::mutex::scoped_lock lock (queueMutex);
while(messageQueue.size() > 0)
{
// the crash is non-reproducible
// works 90% of the time
delete messageQueue.front(); // <- Debug Assertion Failed … _BLOCK_TYPE_IS_VALID
messageQueue.pop_front();
}
}
void MessageQueue::enqueMessage (Message* message)
{
{
boost::mutex::scoped_lock lock (queueMutex);
messageQueue.push_back(message);
}
}
Message* MessageQueue::dequeMessage()
{
boost::mutex::scoped_lock lock (queueMutex);
if (messageQueue.size() == 0)
return nullptr;
Message* message = messageQueue.front();
messageQueue.pop_front();
return message;
}
MessageSystem
template <class MessageType>
void broadcast (MessageType &message)
{
MessageType *internMessage = new MessageType(message);
boost::mutex::scoped_lock lock (mRecipientMapMutex);
std::map <boost::asio::ip::udp::endpoint, MessageQueue *>::iterator it;
for (it = mRecipientMap.begin();
it != mRecipientMap.end();
it++)
{
it->second->enqueMessage(internMessage);
}
}
template <class MessageType>
void post (MessageType &message, boost::asio::ip::udp::endpoint &recipient)
{
MessageType *internMessage = new MessageType(message);
std::map <boost::asio::ip::udp::endpoint, MessageQueue* >::iterator it;
MessageQueue *messageQueue = NULL;
{
boost::mutex::scoped_lock lock (mRecipientMapMutex);
it = mRecipientMap.find (recipient);
if (it != mRecipientMap.end())
messageQueue = it->second;
if(messageQueue)
messageQueue->enqueMessage (internMessage);
}
}
void MessageSystem::sendThreadMain()
{
// copy endpoints to vecotr so it can be
// deleted from map while iterating
std::vector<udp::endpoint> endpoints;
{
boost::mutex::scoped_lock lock (mRecipientMapMutex);
std::map <udp::endpoint, MessageQueue *>::iterator mapIt = mRecipientMap.begin();
while (mapIt != mRecipientMap.end())
{
endpoints.push_back(mapIt->first);
mapIt++;
}
}
std::vector<udp::endpoint>::iterator endpointIt = endpoints.begin();
while (endpointIt != endpoints.end())
{
char sendBuffer[PACKET_SIZE];
int sendBufferPosition = 0;
{
boost::mutex::scoped_lock lock (mRecipientMapMutex);
MessageQueue *messageQueue = mRecipientMap[*endpointIt];
if (messageQueue == nullptr)
{
mRecipientMap.erase(*endpointIt);
endpointIt++;
continue;
}
while (Message *message = messageQueue->dequeMessage())
{
if (sendBufferPosition + message->getSize() > PACKET_SIZE)
{
// put message back and send it later
messageQueue->enqueMessage (message);
break;
}
// copy message into buffer
std::memcpy (
&sendBuffer [sendBufferPosition], message, message->getSize());
sendBufferPosition += message->getSize();
// deleting this message causes a crash if 2 or more
// recipients are registered within MessageSystem
//delete message; <- RANDOM CRASH elsewhere in the program
}
}
.... // more code down here that seems not related to the error
您不會將消息添加到除'broadcast'功能以外的任何其他位置的隊列嗎？ –
有好消息和壞消息。好消息是，這絕對不是由內存泄漏造成的。 –
我不確定這是否是問題，但是您應該在類Message中擁有虛擬析構函數。 – 2011-12-02 10:35:22