threadpsx.cpp

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    return wxTHREAD_NO_ERROR;
}

void wxThreadInternal::Wait()
{
    wxCHECK_RET( !m_isDetached, _T("can't wait for a detached thread") );

    // if the thread we're waiting for is waiting for the GUI mutex, we will
    // deadlock so make sure we release it temporarily
    if ( wxThread::IsMain() )
        wxMutexGuiLeave();

    wxLogTrace(TRACE_THREADS,
               _T("Starting to wait for thread %ld to exit."),
               THR_ID(this));

    // to avoid memory leaks we should call pthread_join(), but it must only be
    // done once so use a critical section to serialize the code below
    {
        wxCriticalSectionLocker lock(m_csJoinFlag);

        if ( m_shouldBeJoined )
        {
            // FIXME shouldn't we set cancellation type to DISABLED here? If
            //       we're cancelled inside pthread_join(), things will almost
            //       certainly break - but if we disable the cancellation, we
            //       might deadlock
            if ( pthread_join(GetId(), &m_exitcode) != 0 )
            {
                // this is a serious problem, so use wxLogError and not
                // wxLogDebug: it is possible to bring the system to its knees
                // by creating too many threads and not joining them quite
                // easily
                wxLogError(_("Failed to join a thread, potential memory leak detected - please restart the program"));
            }

            m_shouldBeJoined = FALSE;
        }
    }

    // reacquire GUI mutex
    if ( wxThread::IsMain() )
        wxMutexGuiEnter();
}

void wxThreadInternal::Pause()
{
    // the state is set from the thread which pauses us first, this function
    // is called later so the state should have been already set
    wxCHECK_RET( m_state == STATE_PAUSED,
                 wxT("thread must first be paused with wxThread::Pause().") );

   wxLogTrace(TRACE_THREADS,
              _T("Thread %ld goes to sleep."), THR_ID(this));

    // wait until the semaphore is Post()ed from Resume()
    m_semSuspend.Wait();
}

void wxThreadInternal::Resume()
{
    wxCHECK_RET( m_state == STATE_PAUSED,
                 wxT("can't resume thread which is not suspended.") );

    // the thread might be not actually paused yet - if there were no call to
    // TestDestroy() since the last call to Pause() for example
    if ( IsReallyPaused() )
    {
       wxLogTrace(TRACE_THREADS,
                  _T("Waking up thread %ld"), THR_ID(this));

        // wake up Pause()
        m_semSuspend.Post();

        // reset the flag
        SetReallyPaused(FALSE);
    }
    else
    {
        wxLogTrace(TRACE_THREADS,
                   _T("Thread %ld is not yet really paused"), THR_ID(this));
    }

    SetState(STATE_RUNNING);
}

// -----------------------------------------------------------------------------
// wxThread static functions
// -----------------------------------------------------------------------------

wxThread *wxThread::This()
{
    return (wxThread *)pthread_getspecific(gs_keySelf);
}

bool wxThread::IsMain()
{
    return (bool)pthread_equal(pthread_self(), gs_tidMain) || gs_tidMain == (pthread_t)-1;
}

void wxThread::Yield()
{
#ifdef HAVE_SCHED_YIELD
    sched_yield();
#endif
}

void wxThread::Sleep(unsigned long milliseconds)
{
    wxMilliSleep(milliseconds);
}

int wxThread::GetCPUCount()
{
#if defined(__LINUX__) && wxUSE_FFILE
    // read from proc (can't use wxTextFile here because it's a special file:
    // it has 0 size but still can be read from)
    wxLogNull nolog;

    wxFFile file(_T("/proc/cpuinfo"));
    if ( file.IsOpened() )
    {
        // slurp the whole file
        wxString s;
        if ( file.ReadAll(&s) )
        {
            // (ab)use Replace() to find the number of "processor: num" strings
            size_t count = s.Replace(_T("processor\t:"), _T(""));
            if ( count > 0 )
            {
                return count;
            }

            wxLogDebug(_T("failed to parse /proc/cpuinfo"));
        }
        else
        {
            wxLogDebug(_T("failed to read /proc/cpuinfo"));
        }
    }
#elif defined(_SC_NPROCESSORS_ONLN)
    // this works for Solaris
    int rc = sysconf(_SC_NPROCESSORS_ONLN);
    if ( rc != -1 )
    {
        return rc;
    }
#endif // different ways to get number of CPUs

    // unknown
    return -1;
}

// VMS is a 64 bit system and threads have 64 bit pointers.
// FIXME: also needed for other systems????
#ifdef __VMS
unsigned long long wxThread::GetCurrentId()
{
    return (unsigned long long)pthread_self();
}

#else // !__VMS

unsigned long wxThread::GetCurrentId()
{
    return (unsigned long)pthread_self();
}

#endif // __VMS/!__VMS


bool wxThread::SetConcurrency(size_t level)
{
#ifdef HAVE_THR_SETCONCURRENCY
    int rc = thr_setconcurrency(level);
    if ( rc != 0 )
    {
        wxLogSysError(rc, _T("thr_setconcurrency() failed"));
    }

    return rc == 0;
#else // !HAVE_THR_SETCONCURRENCY
    // ok only for the default value
    return level == 0;
#endif // HAVE_THR_SETCONCURRENCY/!HAVE_THR_SETCONCURRENCY
}

// -----------------------------------------------------------------------------
// creating thread
// -----------------------------------------------------------------------------

wxThread::wxThread(wxThreadKind kind)
{
    // add this thread to the global list of all threads
    gs_allThreads.Add(this);

    m_internal = new wxThreadInternal();

    m_isDetached = kind == wxTHREAD_DETACHED;
}

wxThreadError wxThread::Create(unsigned int WXUNUSED(stackSize))
{
    if ( m_internal->GetState() != STATE_NEW )
    {
        // don't recreate thread
        return wxTHREAD_RUNNING;
    }

    // set up the thread attribute: right now, we only set thread priority
    pthread_attr_t attr;
    pthread_attr_init(&attr);

#ifdef HAVE_THREAD_PRIORITY_FUNCTIONS
    int policy;
    if ( pthread_attr_getschedpolicy(&attr, &policy) != 0 )
    {
        wxLogError(_("Cannot retrieve thread scheduling policy."));
    }

#ifdef __VMS__
   /* the pthread.h contains too many spaces. This is a work-around */
# undef sched_get_priority_max
#undef sched_get_priority_min
#define sched_get_priority_max(_pol_) \
     (_pol_ == SCHED_OTHER ? PRI_FG_MAX_NP : PRI_FIFO_MAX)
#define sched_get_priority_min(_pol_) \
     (_pol_ == SCHED_OTHER ? PRI_FG_MIN_NP : PRI_FIFO_MIN)
#endif

    int max_prio = sched_get_priority_max(policy),
        min_prio = sched_get_priority_min(policy),
        prio = m_internal->GetPriority();

    if ( min_prio == -1 || max_prio == -1 )
    {
        wxLogError(_("Cannot get priority range for scheduling policy %d."),
                   policy);
    }
    else if ( max_prio == min_prio )
    {
        if ( prio != WXTHREAD_DEFAULT_PRIORITY )
        {
            // notify the programmer that this doesn't work here
            wxLogWarning(_("Thread priority setting is ignored."));
        }
        //else: we have default priority, so don't complain

        // anyhow, don't do anything because priority is just ignored
    }
    else
    {
        struct sched_param sp;
        if ( pthread_attr_getschedparam(&attr, &sp) != 0 )
        {
            wxFAIL_MSG(_T("pthread_attr_getschedparam() failed"));
        }

        sp.sched_priority = min_prio + (prio*(max_prio - min_prio))/100;

        if ( pthread_attr_setschedparam(&attr, &sp) != 0 )
        {
            wxFAIL_MSG(_T("pthread_attr_setschedparam(priority) failed"));
        }
    }
#endif // HAVE_THREAD_PRIORITY_FUNCTIONS

#ifdef HAVE_PTHREAD_ATTR_SETSCOPE
    // this will make the threads created by this process really concurrent
    if ( pthread_attr_setscope(&attr, PTHREAD_SCOPE_SYSTEM) != 0 )
    {
        wxFAIL_MSG(_T("pthread_attr_setscope(PTHREAD_SCOPE_SYSTEM) failed"));
    }
#endif // HAVE_PTHREAD_ATTR_SETSCOPE

    // VZ: assume that this one is always available (it's rather fundamental),
    //     if this function is ever missing we should try to use
    //     pthread_detach() instead (after thread creation)
    if ( m_isDetached )
    {
        if ( pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED) != 0 )
        {
            wxFAIL_MSG(_T("pthread_attr_setdetachstate(DETACHED) failed"));
        }

        // never try to join detached threads
        m_internal->Detach();
    }
    //else: threads are created joinable by default, it's ok

    // create the new OS thread object
    int rc = pthread_create
             (
                m_internal->GetIdPtr(),
                &attr,
                wxPthreadStart,
                (void *)this
             );

    if ( pthread_attr_destroy(&attr) != 0 )
    {
        wxFAIL_MSG(_T("pthread_attr_destroy() failed"));
    }

    if ( rc != 0 )
    {
        m_internal->SetState(STATE_EXITED);

        return wxTHREAD_NO_RESOURCE;
    }

    return wxTHREAD_NO_ERROR;
}

wxThreadError wxThread::Run()
{
    wxCriticalSectionLocker lock(m_critsect);

    wxCHECK_MSG( m_internal->GetId(), wxTHREAD_MISC_ERROR,
                 wxT("must call wxThread::Create() first") );

    return m_internal->Run();
}

// -----------------------------------------------------------------------------
// misc accessors
// -----------------------------------------------------------------------------

void wxThread::SetPriority(unsigned int prio)
{
    wxCHECK_RET( ((int)WXTHREAD_MIN_PRIORITY <= (int)prio) &&
                 ((int)prio <= (int)WXTHREAD_MAX_PRIORITY),
                 wxT("invalid thread priority") );

    wxCriticalSectionLocker lock(m_critsect);

    switch ( m_internal->GetState() )
    {
        case STATE_NEW:
            // thread not yet started, priority will be set when it is
            m_internal->SetPriority(prio);
            break;

        case STATE_RUNNING:
        case STATE_PAUSED:
#ifdef HAVE_THREAD_PRIORITY_FUNCTIONS
#if defined(__LINUX__)
// On Linux, pthread_setschedparam with SCHED_OTHER does not allow
// a priority other than 0.  Instead, we use the BSD setpriority
// which alllows us to set a 'nice' value between 20 to -20.  Only
// super user can set a value less than zero (more negative yields
// higher priority).  setpriority set the static priority of a process,
// but this is OK since Linux is configured as a thread per process.
            {
                float   fPrio;
                float	pSpan;
                int		iPrio;

                // Map Wx priorites (WXTHREAD_MIN_PRIORITY -
                // WXTHREAD_MAX_PRIORITY) into BSD priorities (20 - -20).
                // Do calculation of values instead of hard coding them
                // to make maintenance easier.

                pSpan = ((float)(WXTHREAD_MAX_PRIORITY - WXTHREAD_MIN_PRIORITY)) / 2.0;

                // prio starts as ...................  // value =>  (0) >=  p  <=  (n)

                fPrio = ((float)prio) -  pSpan;        // value =>  (-n) >=  p  <=  (+n)

                fPrio = 0.0 - fPrio;                   // value =>  (+n) <=  p  >=  (-n)

                fPrio = fPrio * (20. / pSpan) + .5;    // value =>  (20) <=  p  >=  (-20)

                iPrio = (int)fPrio;

                // Clamp prio from 20 - -20;
                iPrio = (iPrio > 20)  ?  20 : iPrio;
                iPrio = (iPrio < -20) ? -20 : iPrio;

                if (setpriority(PRIO_PROCESS, 0, iPrio) == -1)
                {
                    wxLogError(_("Failed to set thread priority %d."), prio);
                }
            }
#else // __LINUX__
            {
                struct sched_param sparam;
                sparam.sched_priority = prio;

                if ( pthread_setschedparam(m_internal->GetId(),
                                           SCHED_OTHER, &sparam) != 0 )
                {
                    wxLogError(_("Failed to set thread priority %d."), prio);
                }
            }
#endif // __LINUX__
#endif // HAVE_THREAD_PRIORITY_FUNCTIONS
            break;

        case STATE_EXITED:
        default:
            wxFAIL_MSG(wxT("impossible to set thread priority in this state"));
    }
}

unsigned int wxThread::GetPriority() const
{
    wxCriticalSectionLocker lock((wxCriticalSection &)m_critsect);

    return m_internal->GetPriority();
}

wxThreadIdType wxThread::GetId() const
{
    return (wxThreadIdType) m_internal->GetId();
}

// -----------------------------------------------------------------------------
// pause/resume
// -----------------------------------------------------------------------------

wxThreadError wxThread::Pause()
{
    wxCHECK_MSG( This() != this, wxTHREAD_MISC_ERROR,
                 _T("a thread can't pause itself") );

    wxCriticalSectionLocker lock(m_critsect);

    if ( m_internal->GetState() != STATE_RUNNING )
    {
        wxLogDebug(wxT("Can't pause thread which is not running."));