MINOR: list: define watcher_is_attached()

Define an utility function to report if a watcher is currently attached
on a target. This will notably be used to implement a new CLI command
"show default-server".

diff --git a/include/haproxy/list.h b/include/haproxy/list.h
index 95cc78a75007510a0022abf902d3b7e1c9b42c4f..e4c75dc6f1921702c4fbe6b29afdf65022fe5959 100644 (file)
--- a/include/haproxy/list.h
+++ b/include/haproxy/list.h
@@ -272,6 +272,12 @@ static __inline void watcher_init(struct watcher *w, void *pptr, size_t attach_o
        w->off = attach_off;
 }
 
+/* Returns true if <w> is currently tracking a target else false. */
+static __inline int watcher_is_attached(const struct watcher *w)
+{
+       return MT_LIST_INLIST(&w->el);
+}
+
 /* Tracks <target> via <w> watcher. Invalid if <w> is already attached. */
 static __inline void watcher_attach(struct watcher *w, void *target)
 {