jack2/common/JackProcessSync.h

/*
Copyright (C) 2004-2006 Grame  

This program is free software; you can redistribute it and/or modify
  it under the terms of the GNU General Public License as published by
  the Free Software Foundation; either version 2 of the License, or
  (at your option) any later version.

  This program is distributed in the hope that it will be useful,
  but WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  GNU General Public License for more details.

  You should have received a copy of the GNU General Public License
  along with this program; if not, write to the Free Software
  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.

*/

#ifndef __JackProcessSync__
#define __JackProcessSync__

#include "JackSyncInterface.h"
#include "JackSynchro.h"
#include <pthread.h>
#include <sys/time.h>
#include <unistd.h>

namespace Jack
{

/*!
\brief  A synchronization primitive built using a condition variable.
*/

class JackProcessSync : public JackSyncInterface
{

    private:

        pthread_mutex_t fLock;  // Mutex
        pthread_cond_t fCond;   // Condition variable

    public:

        JackProcessSync(): JackSyncInterface()
        {
            pthread_mutex_init(&fLock, NULL);
            pthread_cond_init(&fCond, NULL);
        }
        virtual ~JackProcessSync()
        {
            pthread_mutex_destroy(&fLock);
            pthread_cond_destroy(&fCond);
        }

        bool Allocate(const char* name)
        {
            return true;
        }

        bool Connect(const char* name)
        {
            return true;
        }

        void Destroy()
        {}

        bool TimedWait(long usec)
        {
            struct timeval T0, T1;
            timespec time;
            struct timeval now;
            int res;

            pthread_mutex_lock(&fLock);
            JackLog("JackProcessSync::Wait time out = %ld\n", usec);
            gettimeofday(&T0, 0);

            static const UInt64	kNanosPerSec = 1000000000ULL;
            static const UInt64	kNanosPerUsec = 1000ULL;
            gettimeofday(&now, 0);
            UInt64 nextDateNanos = now.tv_sec * kNanosPerSec + (now.tv_usec + usec) * kNanosPerUsec;
            time.tv_sec = nextDateNanos / kNanosPerSec;
            time.tv_nsec = nextDateNanos % kNanosPerSec;
            res = pthread_cond_timedwait(&fCond, &fLock, &time);
            if (res != 0)
                jack_error("pthread_cond_timedwait error usec = %ld err = %s", usec, strerror(res));

            gettimeofday(&T1, 0);
            pthread_mutex_unlock(&fLock);
            JackLog("JackProcessSync::Wait finished delta = %5.1lf\n",
                    (1e6 * T1.tv_sec - 1e6 * T0.tv_sec + T1.tv_usec - T0.tv_usec));
            return (res == 0);
        }

        void Wait()
        {
            int res;
            pthread_mutex_lock(&fLock);
            JackLog("JackProcessSync::Wait...\n");
            if ((res = pthread_cond_wait(&fCond, &fLock)) != 0)
                jack_error("pthread_cond_wait error err = %s", strerror(errno));
            pthread_mutex_unlock(&fLock);
            JackLog("JackProcessSync::Wait finished\n");
        }

        void SignalAll()
        {
            //pthread_mutex_lock(&fLock);
            pthread_cond_broadcast(&fCond);
            //pthread_mutex_unlock(&fLock);
        }

};

/*!
\brief  A synchronization primitive built using an inter-process synchronization object.
*/

class JackInterProcessSync : public JackSyncInterface
{

    private:

        JackSynchro* fSynchro;

    public:

        JackInterProcessSync(JackSynchro* synchro): fSynchro(synchro)
        {}
        virtual ~JackInterProcessSync()
        {
            delete fSynchro;
        }

        bool Allocate(const char* name)
        {
            return fSynchro->Allocate(name, 0);
        }

        void Destroy()
        {
            fSynchro->Destroy();
        }

        bool Connect(const char* name)
        {
            return fSynchro->Connect(name);
        }

        bool TimedWait(long usec)
        {
            struct timeval T0, T1;
            JackLog("JackInterProcessSync::Wait...\n");
            gettimeofday(&T0, 0);
            bool res = fSynchro->TimedWait(usec);
            gettimeofday(&T1, 0);
            JackLog("JackInterProcessSync::Wait finished delta = %5.1lf\n",
                    (1e6 * T1.tv_sec - 1e6 * T0.tv_sec + T1.tv_usec - T0.tv_usec));
            return res;
        }

        void Wait()
        {
            fSynchro->Wait();
        }

        void SignalAll()
        {
            fSynchro->SignalAll();
        }
};


} // end of namespace

#endif