Win32/queue(STL)/threads?

[Codeplug]

>> while ( wd->dwQueued )
This is unsynchronized access to a shared variable. Can't do that.

Here is something simple you could do:

class MTCounter : public no_copy
{
    Event m_zeroEvent;
    CriticalSection m_cs;
    int m_counter;

    typedef CriticalSection::scoped_lock lock;

public:
    MTCounter() : m_counter(0)
    {
        if (!m_zeroEvent.Create(true, true)) // manual reset, signaled
            throw std::runtime_error("MTCounter: failed to create event");
    }//constructor

    void increment()
    {
        lock l(m_cs);
        ++m_counter;
        m_zeroEvent.Reset();
    }//increment

    void decrement()
    {
        lock l(m_cs);
        if (m_counter == 0)
            throw std::runtime_error("MTCounter::decrement: count==0");
        --m_counter;
        if (m_counter == 0)
            m_zeroEvent.Signal();
    }//decrement

    bool wait_zero(DWORD to = INFINITE)
    {
        return ::WaitForSingleObject(m_zeroEvent, to) == WAIT_OBJECT_0;
    }//wait_zero
};//MTCounter

So add an MTCounter member to WATCH_DATA. Before the producer calls enqueue(), call MTCounter::increment(). When the consumer thread is done making any more references to the WATCH_DATA pointer, call MTCounter::decrement(). Producer thread calls wait_zero before deleting and exiting. This only works if there is a one-to-one correlation between producer and consumer, and each producer has it's own unique WATCH_DATA instance.

>> EVENT_DATA *ed = new EVENT_DATA(wd, p);
I'm assuming that all data within WATCH_DATA pointer is read-only by the consumer - and the consumer does not touch WATCH_DATA::pBuffer.

I'm also assuming you are copying data out of p within the constructor, and not keeping any references to p or its memory (which belongs to the producer).

>> delete wd;
I also assume that WATCH_DATA's destructor closes handles, and de-allocates any dynamic memory it owns.

>> Mine has (in the last couple days) been boiled down to this.
Your consumer thread should look a lot different from the "QueueThread" code that was originally posted as well :)

gg