tdb2: tdb_foreach()

[ccan] / ccan / tdb2 / tdb2.h

diff --git a/ccan/tdb2/tdb2.h b/ccan/tdb2/tdb2.h
index 051d20a411d8e2d2e71675b05f000a33dff749ae..d5ae329a6029d7659886992dd380e845bd9d2fb4 100644 (file)
--- a/ccan/tdb2/tdb2.h
+++ b/ccan/tdb2/tdb2.h
@@ -617,8 +617,6 @@ enum tdb_attribute_type {
  * This gets an attribute from a TDB which has previously been set (or
  * may return the default values).  Set @attr.base.attr to the
  * attribute type you want get.
- *
- * Currently this does not work for TDB_ATTRIBUTE_OPENHOOK.
  */
 enum TDB_ERROR tdb_get_attribute(struct tdb_context *tdb,
                                 union tdb_attribute *attr);
@@ -672,6 +670,20 @@ const char *tdb_name(const struct tdb_context *tdb);
  */
 int tdb_fd(const struct tdb_context *tdb);
 
+/**
+ * tdb_foreach - iterate through every open TDB.
+ * @fn: the function to call for every TDB
+ * @p: the pointer to hand to @fn
+ *
+ * TDB internally keeps track of all open TDBs; this function allows you to
+ * iterate through them.  If @fn returns non-zero, traversal stops.
+ */
+#define tdb_foreach(fn, p)                                             \
+       tdb_foreach_(typesafe_cb_preargs(int, void *, (fn), (p),        \
+                                        struct tdb_context *), (p))
+
+void tdb_foreach_(int (*fn)(struct tdb_context *, void *), void *p);
+
 /**
  * struct tdb_attribute_base - common fields for all tdb attributes.
  */