/*

 * $Id: thread-st.h$

 * pthread version

 * by Wolfram Gloger 2004

 */

#include <pthread.h>

#include <stdio.h>

pthread_cond_t finish_cond = PTHREAD_COND_INITIALIZER;

pthread_mutex_t finish_mutex = PTHREAD_MUTEX_INITIALIZER;

#ifndef USE_PTHREADS_STACKS

#define USE_PTHREADS_STACKS 0

#endif

#ifndef STACKSIZE

#define STACKSIZE	32768

#endif

struct thread_st {

	char *sp;							/* stack pointer, can be 0 */

	void (*func)(struct thread_st* st);	/* must be set by user */

	pthread_t id;

	int flags;

	struct user_data u;

};

static void

thread_init(void)

{

	printf("Using posix threads.\n");

	pthread_cond_init(&finish_cond, NULL);

	pthread_mutex_init(&finish_mutex, NULL);

}

static void *

thread_wrapper(void *ptr)

{

	struct thread_st *st = (struct thread_st*)ptr;

	/*printf("begin %p\n", st->sp);*/

	st->func(st);

	pthread_mutex_lock(&finish_mutex);

	st->flags = 1;

	pthread_mutex_unlock(&finish_mutex);

	pthread_cond_signal(&finish_cond);

	/*printf("end %p\n", st->sp);*/

	return NULL;

}

/* Create a thread. */

static int

thread_create(struct thread_st *st)

{

	st->flags = 0;

	{

		pthread_attr_t* attr_p = 0;

#if USE_PTHREADS_STACKS

		pthread_attr_t attr;

		pthread_attr_init (&attr);

		if(!st->sp)

			st->sp = malloc(STACKSIZE+16);

		if(!st->sp)

			return -1;

		if(pthread_attr_setstacksize(&attr, STACKSIZE))

			fprintf(stderr, "error setting stacksize");

		else

			pthread_attr_setstackaddr(&attr, st->sp + STACKSIZE);

		/*printf("create %p\n", st->sp);*/

		attr_p = &attr;

#endif

		return pthread_create(&st->id, attr_p, thread_wrapper, st);

	}

	return 0;

}

/* Wait for one of several subthreads to finish. */

static void

wait_for_thread(struct thread_st st[], int n_thr,

				int (*end_thr)(struct thread_st*))

{

	int i;

	pthread_mutex_lock(&finish_mutex);

	for(;;) {

		int term = 0;

		for(i=0; i<n_thr; i++)

			if(st[i].flags) {

				/*printf("joining %p\n", st[i].sp);*/

				if(pthread_join(st[i].id, NULL) == 0) {

					st[i].flags = 0;

					if(end_thr)

						end_thr(&st[i]);

				} else

					fprintf(stderr, "can't join\n");

				++term;

			}

		if(term > 0)

			break;

		pthread_cond_wait(&finish_cond, &finish_mutex);

	}

	pthread_mutex_unlock(&finish_mutex);

}

/*

 * Local variables:

 * tab-width: 4

 * End:

 */