[gnome-commander/gcmd-1-4] Return NULL if no file was given

[Uwe Scholz <uwescholz src gnome org>]

commit 8f6a3870c52c011916db7473d4c45ca1bb1ab1c7
Author: Uwe Scholz <uwescholz src gnome org>
Date:   Wed May 27 21:43:33 2015 +0200

    Return NULL if no file was given

 src/gnome-cmd-file-list.cc |    2 ++
 1 files changed, 2 insertions(+), 0 deletions(-)
---
diff --git a/src/gnome-cmd-file-list.cc b/src/gnome-cmd-file-list.cc
index bf82c6b..fe0362e 100644
--- a/src/gnome-cmd-file-list.cc
+++ b/src/gnome-cmd-file-list.cc
@@ -1159,6 +1159,8 @@ static gboolean on_button_press (GtkCList *clist, GdkEventButton *event, GnomeCm
 
 inline gboolean mime_exec_file (GnomeCmdFile *f)
 {
+    g_return_val_if_fail (f != NULL, FALSE);
+
     if (f->info->type == GNOME_VFS_FILE_TYPE_REGULAR)
     {
         mime_exec_single (f);