_mutex_pthreads.h

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/* === S T A R T =========================================================== */

#ifndef __ETL__MUTEX_PTHREADS_H_
#define __ETL__MUTEX_PTHREADS_H_

/* === H E A D E R S ======================================================= */

#define __USE_GNU

#include <pthread.h>

#ifdef HAVE_SCHED_H
# include <sched.h>
#endif

/* === M A C R O S ========================================================= */

/* === C L A S S E S & S T R U C T S ======================================= */

_ETL_BEGIN_NAMESPACE

class mutex
{
    pthread_mutex_t mtx;
    pthread_t locker;
    int depth;
public:

    mutex()
    {
        pthread_mutexattr_t attr;
        pthread_mutexattr_init(&attr);
        //#ifdef PTHREAD_PRIO_INHERIT
        //pthread_mutexattr_setprioceiling(&attr,PTHREAD_PRIO_INHERIT);
        //#endif
        #ifdef PTHREAD_MUTEX_RECURSIVE
        pthread_mutexattr_settype(&attr,PTHREAD_MUTEX_RECURSIVE);
        #endif
        pthread_mutex_init(&mtx,&attr);
        pthread_mutexattr_destroy(&attr);
        locker=0;
        depth=0;
    }

    ~mutex()
    { pthread_mutex_destroy(&mtx); }


    class lock
    {
        mutex *_mtx;
    public:
        lock(mutex &x):_mtx(&x) { _mtx->lock_mutex(); }
        ~lock() { _mtx->unlock_mutex(); }
        mutex &get() { return *_mtx; }
    };

    void lock_mutex(void)
    {
        if(!locker || locker!=pthread_self())
        {
            pthread_mutex_lock(&mtx);
            locker=pthread_self();
            depth=0;
            return;
        }
        depth++;
    }

    bool try_lock_mutex(void)
    { return !(bool) pthread_mutex_trylock(&mtx); }

    void unlock_mutex(void)
    {
        if(depth)
        {
            depth--;
            return;
        }
        pthread_mutex_unlock(&mtx);
        locker=0;
    }
};

_ETL_END_NAMESPACE

/* === E X T E R N S ======================================================= */

/* === E N D =============================================================== */

#endif