glib-aux: clear iterator in nm_dedup_multi_iter_{next,prev}() at the end

It seems slightly nicer not to leave a dangling pointer at the
end of the iteration. Then you could do something like

    nm_dedup_multi_iter_init(&iter, head_entry);
    while (nm_dedup_multi_iter_next(&iter)) {

        if (some_condition())
            break;
    }
    if (!iter.current)
        printf("iterated to the end\n");

As nm_dedup_multi_iter_next() and nm_dedup_multi_iter_init() are inline
functions, the compiler should even be able to see that the initial
setting becomes unnecessary (the field will be initialized by the
first nm_dedup_multi_iter_next()). Likewise, the final clearing
of the field might also be optimized away at the end of the iteration
(if, as in the common case, the iterator is not accessed afterwards).

1 files changed, 6 insertions, 2 deletions

diff --git a/src/libnm-glib-aux/nm-dedup-multi.h b/src/libnm-glib-aux/nm-dedup-multi.h
index 75cc193363..fb1cb86340 100644
--- a/src/libnm-glib-aux/nm-dedup-multi.h
+++ b/src/libnm-glib-aux/nm-dedup-multi.h
@@ -352,8 +352,10 @@ nm_dedup_multi_iter_next(NMDedupMultiIter *iter)
 {
     g_return_val_if_fail(iter, FALSE);
 
-    if (!iter->_next)
+    if (!iter->_next) {
+        iter->current = NULL;
         return FALSE;
+    }
 
     /* we always look ahead for the next. This way, the user
      * may delete the current entry (but no other entries). */
@@ -370,8 +372,10 @@ nm_dedup_multi_iter_prev(NMDedupMultiIter *iter)
 {
     g_return_val_if_fail(iter, FALSE);
 
-    if (!iter->_prev)
+    if (!iter->_prev) {
+        iter->current = NULL;
         return FALSE;
+    }
 
     /* we always look ahead for the prev. This way, the user
      * may delete the current entry (but no other entries). */