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-rw-r--r--prio-queue.c60
1 files changed, 33 insertions, 27 deletions
diff --git a/prio-queue.c b/prio-queue.c
index c9f8c6d253..e4365b00d6 100644
--- a/prio-queue.c
+++ b/prio-queue.c
@@ -1,18 +1,30 @@
#include "cache.h"
-#include "commit.h"
#include "prio-queue.h"
+static inline int compare(struct prio_queue *queue, int i, int j)
+{
+ int cmp = queue->compare(queue->array[i].data, queue->array[j].data,
+ queue->cb_data);
+ if (!cmp)
+ cmp = queue->array[i].ctr - queue->array[j].ctr;
+ return cmp;
+}
+
+static inline void swap(struct prio_queue *queue, int i, int j)
+{
+ struct prio_queue_entry tmp = queue->array[i];
+ queue->array[i] = queue->array[j];
+ queue->array[j] = tmp;
+}
+
void prio_queue_reverse(struct prio_queue *queue)
{
int i, j;
if (queue->compare != NULL)
die("BUG: prio_queue_reverse() on non-LIFO queue");
- for (i = 0; i <= (j = (queue->nr - 1) - i); i++) {
- struct commit *swap = queue->array[i];
- queue->array[i] = queue->array[j];
- queue->array[j] = swap;
- }
+ for (i = 0; i <= (j = (queue->nr - 1) - i); i++)
+ swap(queue, i, j);
}
void clear_prio_queue(struct prio_queue *queue)
@@ -21,44 +33,42 @@ void clear_prio_queue(struct prio_queue *queue)
queue->nr = 0;
queue->alloc = 0;
queue->array = NULL;
+ queue->insertion_ctr = 0;
}
void prio_queue_put(struct prio_queue *queue, void *thing)
{
- prio_queue_compare_fn compare = queue->compare;
int ix, parent;
/* Append at the end */
ALLOC_GROW(queue->array, queue->nr + 1, queue->alloc);
- queue->array[queue->nr++] = thing;
- if (!compare)
+ queue->array[queue->nr].ctr = queue->insertion_ctr++;
+ queue->array[queue->nr].data = thing;
+ queue->nr++;
+ if (!queue->compare)
return; /* LIFO */
/* Bubble up the new one */
for (ix = queue->nr - 1; ix; ix = parent) {
parent = (ix - 1) / 2;
- if (compare(queue->array[parent], queue->array[ix],
- queue->cb_data) <= 0)
+ if (compare(queue, parent, ix) <= 0)
break;
- thing = queue->array[parent];
- queue->array[parent] = queue->array[ix];
- queue->array[ix] = thing;
+ swap(queue, parent, ix);
}
}
void *prio_queue_get(struct prio_queue *queue)
{
- void *result, *swap;
+ void *result;
int ix, child;
- prio_queue_compare_fn compare = queue->compare;
if (!queue->nr)
return NULL;
- if (!compare)
- return queue->array[--queue->nr]; /* LIFO */
+ if (!queue->compare)
+ return queue->array[--queue->nr].data; /* LIFO */
- result = queue->array[0];
+ result = queue->array[0].data;
if (!--queue->nr)
return result;
@@ -67,18 +77,14 @@ void *prio_queue_get(struct prio_queue *queue)
/* Push down the one at the root */
for (ix = 0; ix * 2 + 1 < queue->nr; ix = child) {
child = ix * 2 + 1; /* left */
- if ((child + 1 < queue->nr) &&
- (compare(queue->array[child], queue->array[child + 1],
- queue->cb_data) >= 0))
+ if (child + 1 < queue->nr &&
+ compare(queue, child, child + 1) >= 0)
child++; /* use right child */
- if (compare(queue->array[ix], queue->array[child],
- queue->cb_data) <= 0)
+ if (compare(queue, ix, child) <= 0)
break;
- swap = queue->array[child];
- queue->array[child] = queue->array[ix];
- queue->array[ix] = swap;
+ swap(queue, child, ix);
}
return result;
}