[libglnx] fdio: Be sure to unset tmpfile's initialized state on cleanup

[Colin Walters <walters src gnome org>]

commit d4c5c02327cc3ac29e40848c53fd1bce392e8ae5
Author: Colin Walters <walters verbum org>
Date:   Tue Jun 27 21:01:46 2017 -0400

    fdio: Be sure to unset tmpfile's initialized state on cleanup
    
    I'm not aware of a problem in practice here, but we should do this on general
    principle. Writing this patch now because I hit a fd leak in the ostree static
    delta processing that was introduced in the tmpfile prep code, but fixed in the
    final port.

 glnx-fdio.c |    9 ++++++++-
 1 files changed, 8 insertions(+), 1 deletions(-)
---
diff --git a/glnx-fdio.c b/glnx-fdio.c
index b5eaa9e..ad43e61 100644
--- a/glnx-fdio.c
+++ b/glnx-fdio.c
@@ -145,10 +145,16 @@ glnx_renameat2_exchange (int olddirfd, const char *oldpath,
   return 0;
 }
 
-/* Deallocate a tmpfile */
+/* Deallocate a tmpfile, closing the fd and deleting the path, if any. This is
+ * normally called by default by the autocleanup attribute, but you can also
+ * invoke this directly.
+ */
 void
 glnx_tmpfile_clear (GLnxTmpfile *tmpf)
 {
+  /* Support being passed NULL so we work nicely in a GPtrArray */
+  if (!tmpf)
+    return;
   if (!tmpf->initialized)
     return;
   if (tmpf->fd == -1)
@@ -160,6 +166,7 @@ glnx_tmpfile_clear (GLnxTmpfile *tmpf)
       (void) unlinkat (tmpf->src_dfd, tmpf->path, 0);
       g_free (tmpf->path);
     }
+  tmpf->initialized = FALSE;
 }
 
 /* Allocate a temporary file, using Linux O_TMPFILE if available.