#include <stdio.h>
#include <stdlib.h>
#include <pthread.h>
#include <unistd.h>

/* Non standard include */
#include <specific_comm.h>


struct communication_assoc assoc_root;
static pthread_mutex_t assoc_lock = PTHREAD_MUTEX_INITIALIZER;
static struct communication_assoc assoc_tmp;
static volatile int init = 0;
volatile int cont = 1;

void initialize_library(void)
{
	assoc_tmp.prev = &assoc_tmp;
	assoc_tmp.next = &assoc_tmp;
	assoc_root.prev = &assoc_root;
	assoc_root.next = &assoc_root;
}

volatile int *init_comm(void)
{
	return &cont;
}

void wait_initialization(void)
{
	while (!init);
}

void add_sender(void)
{
	struct communication_assoc *assoc;

	assoc = create_comm_assoc();
	pthread_mutex_lock(&assoc_lock);
	if (!init)
	{
		initialize_library();
		init = 1;
	}
	assoc->next = assoc_tmp.next;
	assoc_tmp.next->prev = assoc;
	assoc->prev = &assoc_tmp;
	assoc_tmp.next = assoc;
	pthread_mutex_unlock(&assoc_lock);
}

void remove_sender()
{
	printf("remove_communication_channel: Not yet implemented\n");
}

void discover_new_producers(void)
{
	/* If there is some new thread for the write barrier */
	if(&assoc_tmp != assoc_tmp.next)
	{
		/* printf("Adding a new set of producers\n"); */
		pthread_mutex_lock(&assoc_lock);
		/* 
		 * list in assoc_tmp is inserted between assoc_root
		 * and the first elements of assoc_root list
		 */
		assoc_root.next->prev = assoc_tmp.prev;
		assoc_tmp.prev->next = assoc_root.next;
		assoc_root.next = assoc_tmp.next;
		assoc_root.next->prev = &assoc_root;
		/*
		 * assoc_tmp temporary list has been copied in
		 * assoc_root list. assoc_tmp is now alone and so
		 * double linked to itself
		 */
		assoc_tmp.prev = &assoc_tmp;
		assoc_tmp.next = &assoc_tmp;
		pthread_mutex_unlock(&assoc_lock);
	}
}