Function ketama_roll

libCacheSim/dataStructure/ketama/ketama.c:495–594

int
ketama_roll( ketama_continuum* contptr, char* filename )
{
    if (shm_ids == NULL) {
        init_shm_id_tracker();
    }

    if (shm_data == NULL) {
        init_shm_data_tracker();
    }   

    strcpy( k_error, "" );

    key_t key;
    int shmid;
    int *data;
    int sem_set_id;

//     setlogmask( LOG_UPTO ( LOG_NOTICE | LOG_ERR | LOG_INFO ) );
//     openlog( "ketama", LOG_CONS | LOG_PID | LOG_NDELAY, LOG_LOCAL1 );

    key = ftok( filename, 'R' );
    if ( key == -1 )
    {
        set_error( "Invalid filename specified: %s", filename );
        return 0;
    }

    *contptr = malloc( sizeof( continuum ) );
    (*contptr)->numpoints = 0;
    (*contptr)->array = 0;
    (*contptr)->modtime = 0;

    sem_set_id = ketama_sem_init( key );

    int sanity = 0;
    while ( semctl( sem_set_id, 0, GETVAL, 0 ) == 2 )
    {
        // wait for the continuum creator to finish, but don't block others
        usleep( 5 );

        // if we are waiting for > 1 second, take drastic action:
        if(++sanity > 1000000)
	{
            usleep( rand()%50000 );
            ketama_sem_unlock( sem_set_id );
	    break;
        }
    }

    time_t modtime = file_modtime( filename );
    time_t* fmodtime = 0;
    while ( !fmodtime || modtime != *fmodtime )
    {
        shmid = shmget( key, MC_SHMSIZE, 0 ); // read only attempt.
        track_shm_id(shmid);

		data = shmat( shmid, (void *)0, SHM_RDONLY );