[deliverable/binutils-gdb.git] / libiberty / insque.c

/* insque(3C) routines
   This file is in the public domain.  */

/*
NAME
	insque, remque -- insert, remove an element from a queue

SYNOPSIS
	struct qelem {
	  struct qelem *q_forw;
	  struct qelem *q_back;
	  char q_data[];
	};

	void insque (struct qelem *elem, struct qelem *pred)

	void remque (struct qelem *elem)

DESCRIPTION
	Routines to manipulate queues built from doubly linked lists.
	The insque routine inserts ELEM in the queue immediately after
	PRED.  The remque routine removes ELEM from its containing queue.
*/


struct qelem {
  struct qelem *q_forw;
  struct qelem *q_back;
};


void
insque (elem, pred)
  struct qelem *elem;
  struct qelem *pred;
{
  elem -> q_forw = pred -> q_forw;
  pred -> q_forw -> q_back = elem;
  elem -> q_back = pred;
  pred -> q_forw = elem;
}


void
remque (elem)
  struct qelem *elem;
{
  elem -> q_forw -> q_back = elem -> q_back;
  elem -> q_back -> q_forw = elem -> q_forw;
}
Commit	Line	Data
252b5132 RH	1	/* insque(3C) routines
	2	This file is in the public domain. */
	3
	4	/*
	5	NAME
	6	insque, remque -- insert, remove an element from a queue
	7
	8	SYNOPSIS
	9	struct qelem {
	10	struct qelem *q_forw;
	11	struct qelem *q_back;
	12	char q_data[];
	13	};
	14
	15	void insque (struct qelem elem, struct qelem pred)
	16
	17	void remque (struct qelem *elem)
	18
	19	DESCRIPTION
	20	Routines to manipulate queues built from doubly linked lists.
	21	The insque routine inserts ELEM in the queue immediately after
	22	PRED. The remque routine removes ELEM from its containing queue.
	23	*/
	24
	25
	26	struct qelem {
	27	struct qelem *q_forw;
	28	struct qelem *q_back;
	29	};
	30
	31
	32	void
	33	insque (elem, pred)
	34	struct qelem *elem;
	35	struct qelem *pred;
	36	{
	37	elem -> q_forw = pred -> q_forw;
	38	pred -> q_forw -> q_back = elem;
	39	elem -> q_back = pred;
	40	pred -> q_forw = elem;
	41	}
	42
	43
	44	void
	45	remque (elem)
	46	struct qelem *elem;
	47	{
	48	elem -> q_forw -> q_back = elem -> q_back;
	49	elem -> q_back -> q_forw = elem -> q_forw;
	50	}