X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?a=blobdiff_plain;f=src%2Fbasic%2Fprioq.c;h=d55b348c22f2ec82d13d2dacff33dcc3f808abb7;hb=27edf6f36e27bff66b04908b4dcebd359ae08116;hp=b89888be0e8d5460313ffc3e9712856f214ce5d2;hpb=3b22396a4b2767a98172f6915929c47738cb0a1e;p=elogind.git

diff --git a/src/basic/prioq.c b/src/basic/prioq.c
index b89888be0..d55b348c2 100644
--- a/src/basic/prioq.c
+++ b/src/basic/prioq.c
@@ -19,6 +19,16 @@
   along with systemd; If not, see <http://www.gnu.org/licenses/>.
 ***/
 
+/*
+ * Priority Queue
+ * The prioq object implements a priority queue. That is, it orders objects by
+ * their priority and allows O(1) access to the object with the highest
+ * priority. Insertion and removal are Θ(log n). Optionally, the caller can
+ * provide a pointer to an index which will be kept up-to-date by the prioq.
+ *
+ * The underlying algorithm used in this implementation is a Heap.
+ */
+
 #include "util.h"
 #include "prioq.h"
 
@@ -101,7 +111,7 @@ static unsigned shuffle_up(Prioq *q, unsigned idx) {
 
                 k = (idx-1)/2;
 
-                if (q->compare_func(q->items[k].data, q->items[idx].data) < 0)
+                if (q->compare_func(q->items[k].data, q->items[idx].data) <= 0)
                         break;
 
                 swap(q, idx, k);