From e6297121977cf9aac79b4210f6cae93bd50d58fc Mon Sep 17 00:00:00 2001
From: wwp <subscript@free.fr>
Date: Wed, 8 Jun 2016 14:44:25 +0300
Subject: [PATCH] Ticket #3562: fix Glib-critical asserts in empty WListbox.

Signed-off-by: Andrew Borodin <aborodin@vmail.ru>
---
 lib/widget/listbox.c | 27 ++++++++++++++++++---------
 1 file changed, 18 insertions(+), 9 deletions(-)

diff --git a/lib/widget/listbox.c b/lib/widget/listbox.c
index 6e89300a7..ca593413b 100644
--- a/lib/widget/listbox.c
+++ b/lib/widget/listbox.c
@@ -52,7 +52,7 @@ const global_keymap_t *listbox_map = NULL;
 /*** file scope macro definitions ****************************************************************/
 
 /* Gives the position of the last item. */
-#define LISTBOX_LAST(l) (g_queue_is_empty ((l)->list) ? 0 : (int) g_queue_get_length ((l)->list) - 1)
+#define LISTBOX_LAST(l) (listbox_is_empty (l) ? 0 : (int) g_queue_get_length ((l)->list) - 1)
 
 /*** file scope type declarations ****************************************************************/
 
@@ -231,10 +231,13 @@ listbox_y_pos (WListbox * l, int y)
 static void
 listbox_fwd (WListbox * l, gboolean wrap)
 {
-    if ((guint) l->pos + 1 < g_queue_get_length (l->list))
-        listbox_select_entry (l, l->pos + 1);
-    else if (wrap)
-        listbox_select_first (l);
+    if (!listbox_is_empty (l))
+    {
+        if ((guint) l->pos + 1 < g_queue_get_length (l->list))
+            listbox_select_entry (l, l->pos + 1);
+        else if (wrap)
+            listbox_select_first (l);
+    }
 }
 
 /* --------------------------------------------------------------------------------------------- */
@@ -250,10 +253,13 @@ listbox_fwd_n (WListbox * l, int n)
 static void
 listbox_back (WListbox * l, gboolean wrap)
 {
-    if (l->pos > 0)
-        listbox_select_entry (l, l->pos - 1);
-    else if (wrap)
-        listbox_select_last (l);
+    if (!listbox_is_empty (l))
+    {
+        if (l->pos > 0)
+            listbox_select_entry (l, l->pos - 1);
+        else if (wrap)
+            listbox_select_last (l);
+    }
 }
 
 /* --------------------------------------------------------------------------------------------- */
@@ -402,6 +408,9 @@ listbox_do_action (WListbox * l)
 {
     int action;
 
+    if (listbox_is_empty (l))
+        return;
+
     if (l->callback != NULL)
         action = l->callback (l);
     else
-- 
2.11.4.GIT