philosopher.c

来自「C++ SOCKET 类」· C语言 代码 · 共 49 行

#include "philosopher.h"

using namespace std;

philosopher::philosopher(int n, int forks, void *arg)
  : Pthread(arg)
{
  _nr    = n;
  _forks = forks;
  _count = forks;
}

philosopher::~philosopher()
{
}

static void rand_sleep(int max)
{
  double x = rand();

  x /= RAND_MAX;
  sleep( (int)(x*max) );
}

int philosopher::thread(void *ptr)
{
  int lfork,rfork;

  lfork = _nr-1 >= 0 ? _nr-1 : _forks-1;
  rfork = lfork+1 >= _forks ? 0 : lfork+1;
  application = (dining *)ptr;
  while(_count-- > 0) {
    cout << "Philosopher " << _nr;
    cout << " looking for (" << lfork << ',' << rfork << ")" << endl;
    while( application->get_forks(_nr) == false )
      usleep(10);
    cout << "Philosopher " << _nr << " using (" << lfork << ',' <<  rfork << ")\n";
    rand_sleep( 20 );
    cout << "Philosopher " << _nr << ": sleeping\n";
    application->put_forks(_nr);
    rand_sleep( 20 );
  }
  application->finished(_nr);
  cout << _nr << " has finished dining." << endl;
  return 0;
}