newqueue.c

来自「TCP-IP红宝书源代码」· C语言 代码 · 共 27 行

/* newqueue.c  -  newqueue */

#include <conf.h>
#include <kernel.h>
#include <q.h>

/*------------------------------------------------------------------------
 * newqueue  --  initialize a new list in the q structure
 *------------------------------------------------------------------------
 */
int	newqueue()
{
	struct	qent	*hptr;
	struct	qent	*tptr;
	int	hindex, tindex;

	hptr = &q[ hindex=nextqueue++]; /* assign and rememeber queue	*/
	tptr = &q[ tindex=nextqueue++]; /* index values for head&tail	*/
	hptr->qnext = tindex;
	hptr->qprev = EMPTY;
	hptr->qkey  = MININT;
	tptr->qnext = EMPTY;
	tptr->qprev = hindex;
	tptr->qkey  = MAXINT;
	return(hindex);
}