From: Sebastian Harl <sh@tokkee.org>
Date: Mon, 21 Apr 2014 16:52:48 +0000 (+0200)
Subject: utils llist: Added sdb_llist_clear().
X-Git-Tag: sysdb-0.1.0~110
X-Git-Url: https://git.tokkee.org/?p=sysdb.git;a=commitdiff_plain;h=ed920688e7cdc9fd497044379c8d14da0dfaebeb

utils llist: Added sdb_llist_clear().

This function clears the list by removing all elements and releasing the
included objects. It's similar to destroy() but does not actually release the
list object itself.
---

diff --git a/src/include/utils/llist.h b/src/include/utils/llist.h
index f557c9d..28816a6 100644
--- a/src/include/utils/llist.h
+++ b/src/include/utils/llist.h
@@ -56,6 +56,14 @@ sdb_llist_create(void);
 void
 sdb_llist_destroy(sdb_llist_t *list);
 
+/*
+ * sdb_llist_clear:
+ * Remove all elements from the list, releasing the included objects
+ * (decrement the ref-count).
+ */
+void
+sdb_llist_clear(sdb_llist_t *list);
+
 /*
  * sdb_llist_clone:
  * Clone an existing list. The objects stored in the list will not be copied
diff --git a/src/utils/llist.c b/src/utils/llist.c
index e042c99..f9bf722 100644
--- a/src/utils/llist.c
+++ b/src/utils/llist.c
@@ -69,6 +69,26 @@ struct sdb_llist_iter {
  * private helper functions
  */
 
+static void
+llist_clear(sdb_llist_t *list)
+{
+	sdb_llist_elem_t *elem;
+
+	assert(list);
+	elem = list->head;
+	while (elem) {
+		sdb_llist_elem_t *tmp = elem->next;
+
+		sdb_object_deref(elem->obj);
+		free(elem);
+
+		elem = tmp;
+	}
+
+	list->head = list->tail = NULL;
+	list->length = 0;
+} /* llist_clear */
+
 /* Insert a new element after 'elem'. If 'elem' is NULL, insert at the head of
  * the list. */
 static int
@@ -213,31 +233,27 @@ sdb_llist_clone(sdb_llist_t *list)
 void
 sdb_llist_destroy(sdb_llist_t *list)
 {
-	sdb_llist_elem_t *elem;
-
 	if (! list)
 		return;
 
 	pthread_rwlock_wrlock(&list->lock);
-
-	elem = list->head;
-	while (elem) {
-		sdb_llist_elem_t *tmp = elem->next;
-
-		sdb_object_deref(elem->obj);
-		free(elem);
-
-		elem = tmp;
-	}
-
-	list->head = list->tail = NULL;
-	list->length = 0;
-
+	llist_clear(list);
 	pthread_rwlock_unlock(&list->lock);
 	pthread_rwlock_destroy(&list->lock);
 	free(list);
 } /* sdb_llist_destroy */
 
+void
+sdb_llist_clear(sdb_llist_t *list)
+{
+	if (! list)
+		return;
+
+	pthread_rwlock_wrlock(&list->lock);
+	llist_clear(list);
+	pthread_rwlock_unlock(&list->lock);
+} /* sdb_llist_clear */
+
 int
 sdb_llist_append(sdb_llist_t *list, sdb_object_t *obj)
 {
diff --git a/t/utils/llist_test.c b/t/utils/llist_test.c
index e8d366c..cc9954d 100644
--- a/t/utils/llist_test.c
+++ b/t/utils/llist_test.c
@@ -115,6 +115,25 @@ START_TEST(test_destroy)
 }
 END_TEST
 
+START_TEST(test_clear)
+{
+	size_t i;
+	populate();
+	sdb_llist_clear(list);
+
+	for (i = 0; i < SDB_STATIC_ARRAY_LEN(golden_data); ++i) {
+		fail_unless(golden_data[i].ref_cnt == 1,
+				"sdb_llist_clear() did not deref element %s",
+				golden_data[i].name);
+	}
+
+	i = sdb_llist_len(list);
+	fail_unless(i == 0,
+			"sdb_llist_clear() left %zu elements in the list; "
+			"expected: 0", i);
+}
+END_TEST
+
 START_TEST(test_append)
 {
 	size_t i;
@@ -361,6 +380,7 @@ util_llist_suite(void)
 	tcase_add_checked_fixture(tc, setup, teardown);
 	tcase_add_test(tc, test_clone);
 	tcase_add_test(tc, test_destroy);
+	tcase_add_test(tc, test_clear);
 	tcase_add_test(tc, test_append);
 	tcase_add_test(tc, test_insert);
 	tcase_add_test(tc, test_validate_insert);