More scheduling

1 files changed, 17 insertions, 1 deletions

diff --git a/src/lib/pqueue.c b/src/lib/pqueue.c
index c080bb2..cf0611f 100644
--- a/src/lib/pqueue.c
+++ b/src/lib/pqueue.c
@@ -35,7 +35,8 @@
 #define parent(i) ((i) >> 1)
 
 struct pqueue *pqueue_init(size_t n, pqueue_cmp_pri_f cmppri,
-			   pqueue_get_pri_f getpri, pqueue_set_pos_f setpos)
+			   pqueue_get_pri_f getpri, pqueue_set_pri_f setpri,
+			   pqueue_get_pos_f getpos, pqueue_set_pos_f setpos)
 {
 	struct pqueue *q;
 
@@ -51,7 +52,9 @@ struct pqueue *pqueue_init(size_t n, pqueue_cmp_pri_f cmppri,
 	q->size = 1;
 	q->avail = q->step = (n + 1); /* see comment above about n+1 */
 	q->cmppri = cmppri;
+	q->setpri = setpri;
 	q->getpri = getpri;
+	q->getpos = getpos;
 	q->setpos = setpos;
 
 	return q;
@@ -144,6 +147,19 @@ int pqueue_insert(struct pqueue *q, void *d)
 	return 0;
 }
 
+void pqueue_change_priority(struct pqueue *q, pqueue_pri_t new_pri, void *d)
+{
+	size_t posn;
+	pqueue_pri_t old_pri = q->getpri(d);
+
+	q->setpri(d, new_pri);
+	posn = q->getpos(d);
+	if (q->cmppri(old_pri, new_pri))
+		bubble_up(q, posn);
+	else
+		percolate_down(q, posn);
+}
+
 void *pqueue_pop(struct pqueue *q)
 {
 	void *head;