tlist: remove unused var warning in example.
[ccan] / ccan / tlist / tlist.h
index 9f62869b2b19c23c3fcb812ed2a6420a45a847a7..937a834c0184fb4d54928ca57db9668a929b1f8c 100644 (file)
 /**
  * tlist_top - get the first entry in a list
  * @h: the tlist
- * @type: the type of the entry
  * @member: the list_node member of the type
  *
  * If the list is empty, returns NULL.
  *
  * Example:
  *     struct child *first;
- *     first = tlist_top(&parent->children, struct child, list);
+ *     first = tlist_top(&parent->children, list);
+ *     if (!first)
+ *             printf("Empty list!\n");
  */
-#define tlist_top(h, type, member) \
-       list_top(tlist_raw((h), (type *)NULL), type, member)
+#define tlist_top(h, member)                                           \
+       ((tcon_type((h), canary))                                       \
+        list_top_(&(h)->raw,                                           \
+                  (char *)(&(h)->_tcon[0].canary->member) -            \
+                  (char *)((h)->_tcon[0].canary)))
 
 /**
  * tlist_tail - get the last entry in a list
  * @h: the tlist
- * @type: the type of the entry
  * @member: the list_node member of the type
  *
  * If the list is empty, returns NULL.
  *
  * Example:
  *     struct child *last;
- *     last = tlist_tail(&parent->children, struct child, list);
+ *     last = tlist_tail(&parent->children, list);
+ *     if (!last)
+ *             printf("Empty list!\n");
  */
-#define tlist_tail(h, type, member) \
-       list_tail(tlist_raw((h), (type *)NULL), type, member)
+#define tlist_tail(h, member)                                          \
+       ((tcon_type((h), canary))                                       \
+        list_tail_(&(h)->raw,                                          \
+                   (char *)(&(h)->_tcon[0].canary->member) -           \
+                   (char *)((h)->_tcon[0].canary)))
 
 /**
  * tlist_for_each - iterate through a list.
 #define tlist_for_each(h, i, member)                                   \
        list_for_each(tlist_raw((h), (i)), (i), member)
 
+/**
+ * tlist_for_each - iterate through a list backwards.
+ * @h: the tlist
+ * @i: an iterator of suitable type for this list.
+ * @member: the list_node member of @i
+ *
+ * This is a convenient wrapper to iterate @i over the entire list.  It's
+ * a for loop, so you can break and continue as normal.
+ *
+ * Example:
+ *     tlist_for_each_rev(&parent->children, child, list)
+ *             printf("Name: %s\n", child->name);
+ */
+#define tlist_for_each_rev(h, i, member)                                       \
+       list_for_each_rev(tlist_raw((h), (i)), (i), member)
+
 /**
  * tlist_for_each_safe - iterate through a list, maybe during deletion
  * @h: the tlist