X-Git-Url: http://pileus.org/git/?a=blobdiff_plain;f=util.c;h=18f98dc4f17859e5c5724a8d25ed39271ba89e70;hb=f0adaa78963ffc8b870059d5787079fbbd7c52a5;hp=24100f2243d6576d8481109a17a43c614d4a7c1a;hpb=5dd54ab27b27c888741e5700aad89226009eb449;p=wmpus

diff --git a/util.c b/util.c
index 24100f2..18f98dc 100644
--- a/util.c
+++ b/util.c
@@ -15,10 +15,22 @@ list_t *list_insert(list_t *next, void *data)
 	return node;
 }
 
+void list_insert_after(list_t *prev, void *data)
+{
+	// prev must be valid,
+	// as we cannot return the original list head
+	list_t *node = new0(list_t);
+	node->data = data;
+	node->prev = prev;
+	node->next = prev->next;
+	prev->next = node;
+	if (node->next) node->next->prev = node;
+}
+
 list_t *list_append(list_t *head, void *data)
 {
 	list_t *last = head;
-	while (last->next)
+	while (last && last->next)
 		last = last->next;
 	list_t *node = new0(list_t);
 	node->data = data;
@@ -45,6 +57,21 @@ int list_length(list_t *node)
 	return len;
 }
 
+list_t *list_last(list_t *list)
+{
+	while (list && list->next)
+		list = list->next;
+	return list;
+}
+
+list_t *list_find(list_t *list, void *data)
+{
+	for (list_t *cur = list; cur; cur = cur->next)
+		if (cur->data == data)
+			return cur;
+	return NULL;
+}
+
 /* Misc */
 int error(char *fmt, ...)
 {