boost::thread

From:
Christopher <cpisz@austin.rr.com>
Newsgroups:
comp.lang.c++
Date:
Mon, 1 Aug 2011 11:20:37 -0700 (PDT)
Message-ID:
<91a83549-6c4e-4102-87fe-ae835488aafc@f35g2000vbr.googlegroups.com>
I am trying to make a thread object, so I can later have better
control of threads and the resources they are using. So, I started
wrapping up a boost::thread.

//---------------------------------------------------------------------------------------------------------------------------------------------
// BaseThread.h
#include <boost/thread/thread.hpp>

//------------------------------------------------------------------------------
/// \brief Thread object that performs a task that is to run once (non-
looped)
/// \detail Derive from this class and implement the Work method to
define the
/// work this thread is to perform
class BaseThread
{
public:

    BaseThread();

    /// \brief Deconstructor
    /// \detail It is required that a derived class make a call to
thread_.join()
    /// in its deconstructor
    virtual ~BaseThread();

    virtual void Start();
    virtual int Work() = 0;

protected:

    void Run();

    boost::thread thread_;
};

//---------------------------------------------------------------------------------------------------------------------------------------------
// BaseThread.cpp

#include "BaseThread.h"

//------------------------------------------------------------------------------
BaseThread::BaseThread()
{
}

//------------------------------------------------------------------------------
BaseThread::~BaseThread()
{
    // Wait for the thread to complete
    thread_.join();

    // DEBUG - Does join wait?
    int x = 1;
}

//------------------------------------------------------------------------------
void BaseThread::Start()
{
    boost::thread newThread(boost::bind(&BaseThread::Run, this));
    thread_.swap(newThread);
}

//------------------------------------------------------------------------------
void BaseThread::Run()
{
    this->Work();
}

I am kind of winging it here just going off of the boost documentation
and guessing at what I should be doing. This code has a problem in
that in order for us to wait for the thread to complete, the derived
class is going to have to call thread_.join(). That leaves a bad taste
in my mouth as I'd rather the base class take care of all the details,
and all the derived class has to worry about is providing a Work
method.

This class doesn't provide much that boost::thread doesn't already
have, but I want to make different classes for additonal requirements.
One of which I have in mind is a thread with looped work and a start,
stop, method.

Making an object out of it will also probably help with derving
classes that take care of locking their data...or at least organize it
a bit.

So the question is, is there a way I can avoid the requirement here
that derived classes call thread_.join() and do something different in
the base class?

I'll probably have more questions as I progress.

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