How to properly manage messages sent to a thread in C++ - c++

Question

In my Android app, I use C++ to do some work. In my C++ code, I use a thread to do some tasks. Using this example and this example, here is how I proceed (I simplified the actual code to keep it easy to read):
std::thread* threadLocal;
std::queue<ThreadMessage*> queueLocale;
std::mutex mutexLocal;
std::condition_variable cvLocal;
struct ThreadMessage
{
ThreadMessage(int i)
{
id = i;
}
int id;
};
void MyWorkerThread::createThread()
{
if (!threadLocal)
{
threadLocal = new std::thread(&MyWorkerThread::process, this);
}
}
void MyWorkerThread::sendTask1()
{
if (threadLocal)
{
// message:
ThreadMessage* threadMessage = new ThreadMessage(MSG_TASK_1);
// send the message:
std::unique_lock<std::mutex> lock(mutexLocal);
queueLocale.push(std::move(threadMessage));
cvLocal.notify_one();
}
}
void MyWorkerThread::sendTask2()
{
if (threadLocal)
{
// message:
ThreadMessage* threadMessage = new ThreadMessage(MSG_TASK_2);
// send the message:
std::unique_lock<std::mutex> lock(mutexLocal);
queueLocale.push(std::move(threadMessage));
cvLocal.notify_one();
}
}
void MyWorkerThread::process()
{
while (1)
{
// init :
ThreadMessage* threadMessage = 0;
// waiting for messages :
{
std::unique_lock<std::mutex> lock(mutexLocal);
while (queueLocale.empty())
{
cvLocal.wait(lock);
}
threadMessage = std::move(queueLocale.front());
queueLocale.pop();
}
// tasks :
switch (threadMessage->id)
{
case MSG_TASK_1:
{
doSomeWork1();
delete threadMessage;
break;
}
case MSG_TASK_2:
{
doSomeWork2();
delete threadMessage;
break;
}
default:
{
delete threadMessage;
break;
}
}
}
}
It works well in most cases, but sometimes, my app crashes when a delete threadMessage is called, and I don't understand why (since I don't see how it can be called twice on a same object).
Here are the reasons why I need to send messages to a thread, instead of just creating new threads each time I want to run doSomeWork1() or doSomeWork2():
The doSomeWork1() and doSomeWork2() functions have to be executed in the same thread
One of those functions is very frequently called (approx. 200 times / sec), so I don't want to create a thread each time
So my question is: what is the proper way to send a message to a thread, and manage it inside the thread, to avoid error on the delete?
Thanks for your help.