[network-manager-openvpn] service: fix compilation with GLib 2.32

[Jiří Klimeš <jklimes src gnome org>]

commit 5afb8eb0128d695376d6165a47e313dae5157f0d
Author: Jiří Klimeš <jklimes redhat com>
Date:   Mon Nov 10 14:05:50 2014 +0100

    service: fix compilation with GLib 2.32
    
    g_clear_pointer() is only available from GLib 2.34 and higher.
    
    Regression was introduced in 627453c2dec8d5eb4fbc775b3d9afa7c25491350.

 common/nm-glib-compat.h  |   49 ++++++++++++++++++++++++++++++++++++++++++++++
 src/nm-openvpn-service.c |    1 +
 2 files changed, 50 insertions(+), 0 deletions(-)
---
diff --git a/common/nm-glib-compat.h b/common/nm-glib-compat.h
new file mode 100644
index 0000000..d559df1
--- /dev/null
+++ b/common/nm-glib-compat.h
@@ -0,0 +1,49 @@
+/* -*- Mode: C; tab-width: 4; indent-tabs-mode: t; c-basic-offset: 4 -*- */
+/*
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Copyright 2014 Red Hat, Inc.
+ */
+
+#ifndef __NM_GLIB_COMPAT_H__
+#define __NM_GLIB_COMPAT_H__
+
+#include <glib.h>
+#include <glib-object.h>
+
+
+#if !GLIB_CHECK_VERSION(2,34,0)
+
+#define g_clear_pointer(pp, destroy)     \
+       G_STMT_START { \
+               G_STATIC_ASSERT (sizeof *(pp) == sizeof (gpointer)); \
+               /* Only one access, please */ \
+               gpointer *_pp = (gpointer *) (pp); \
+               gpointer _p; \
+               /* This assignment is needed to avoid a gcc warning */ \
+               GDestroyNotify _destroy = (GDestroyNotify) (destroy); \
+         \
+               (void) (0 ? (gpointer) *(pp) : 0); \
+               do \
+                       _p = g_atomic_pointer_get (_pp); \
+               while G_UNLIKELY (!g_atomic_pointer_compare_and_exchange (_pp, _p, NULL)); \
+         \
+               if (_p) \
+                       _destroy (_p); \
+       } G_STMT_END
+
+#endif
+
+#endif  /* __NM_GLIB_COMPAT_H__ */
diff --git a/src/nm-openvpn-service.c b/src/nm-openvpn-service.c
index 0f839bd..44ece16 100644
--- a/src/nm-openvpn-service.c
+++ b/src/nm-openvpn-service.c
@@ -55,6 +55,7 @@
 #include "nm-openvpn-service.h"
 #include "nm-utils.h"
 #include "common/utils.h"
+#include "common/nm-glib-compat.h"
 
 #if !defined(DIST_VERSION)
 # define DIST_VERSION VERSION