Fix memory leak in pqueue_test.

pqueue_free requires the queue be empty.

Change-Id: I633e18fe71ddec51d6005210fcb6570ef53b9808
Reviewed-on: https://boringssl-review.googlesource.com/3410
Reviewed-by: Adam Langley <agl@google.com>

ssl/pqueue/pqueue.c

@@ -56,6 +56,7 @@
 
 #include <openssl/pqueue.h>
 
+#include <assert.h>
 #include <string.h>
 
 #include <openssl/mem.h>
@@ -104,6 +105,8 @@ void pqueue_free(pqueue_s *pq) {
     return;
   }
 
+  /* The queue must be empty. */
+  assert(pq->items == NULL);
   OPENSSL_free(pq);
 }
 

ssl/pqueue/pqueue_test.c

@@ -19,6 +19,17 @@
 #include <openssl/ssl.h>
 
 
+static void clear_and_free_queue(pqueue q) {
+  for (;;) {
+    pitem *item = pqueue_pop(q);
+    if (item == NULL) {
+      break;
+    }
+    pitem_free(item);
+  }
+  pqueue_free(q);
+}
+
 static int trivial(void) {
   pqueue q = pqueue_new();
   if (q == NULL) {
@@ -37,7 +48,7 @@ static int trivial(void) {
     return 0;
   }
   pitem_free(item);
-  pqueue_free(q);
+  clear_and_free_queue(q);
   return 1;
 }
 
@@ -101,7 +112,7 @@ static int fixed_random(void) {
     }
     curr = next;
   }
-  pqueue_free(q);
+  clear_and_free_queue(q);
   return 1;
 }