void dlist_node_tail_push(dlist_t *list, dlist_node_t *node)
{
assert(list != NULL);
assert(list->lock == 0);
assert(node != NULL);
dlist_assert(list);
/* eject the node from whatever list it is currently on */
dlist_node_eject(node->list, node);
/* if we don't have a tail node, we don't have a head node set either */
if(list->tail == NULL)
{
list->head = node;
}
else
{
list->tail->next = node;
}
/* the current tail node will be second to last on the list */
node->prev = list->tail;
node->list = list;
list->tail = node;
list->length++;
dlist_assert(list);
return;
}
/*
* fds_select_assemble
*
* given a list of scamper_fd_poll_t structures held in a list, compose an
* fd_set for them to pass to select.
*/
static fd_set *fds_select_assemble(dlist_t *fds, fd_set *fdset, int *nfds)
{
scamper_fd_poll_t *fdp;
dlist_node_t *node;
int count = 0;
FD_ZERO(fdset);
node = dlist_head_node(fds);
while(node != NULL)
{
/* file descriptor associated with the node */
fdp = (scamper_fd_poll_t *)dlist_node_item(node);
/* get the next node incase this node is subsequently removed */
node = dlist_node_next(node);
/* if there is nothing using this fdn any longer, then stop polling it */
if(fdp->fdn->refcnt == 0 && fdp->fdn->rc0 == NULL)
{
fd_refcnt_0(fdp->fdn);
continue;
}
/* if the inactive flag is set, then skip over this file descriptor */
if((fdp->flags & SCAMPER_FD_POLL_FLAG_INACTIVE) != 0)
{
dlist_node_eject(fds, fdp->node);
fdp->list = NULL;
continue;
}
/* monitor this file descriptor */
FD_SET(fdp->fdn->fd, fdset);
count++;
/* update the maxfd seen if appropriate */
if(*nfds < fdp->fdn->fd)
{
*nfds = fdp->fdn->fd;
}
}
/*
* if there are no fds in the set to monitor, then return a null pointer
* to pass to select
*/
if(count == 0)
{
return NULL;
}
return fdset;
}