gio: Add API for identifying system FS types and device paths

This is needed by gnome-control-center and gnome-settings-daemon; it
makes existing checks from gunixmounts.c public.

Signed-off-by: Philip Withnall <withnall@endlessm.com>

https://bugzilla.gnome.org/show_bug.cgi?id=788927

gio/tests/unix-mounts.c

@@ -0,0 +1,57 @@
+/* GLib testing framework examples and tests
+ *
+ * Copyright © 2017 Endless Mobile, Inc.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General
+ * Public License along with this library; if not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <glib.h>
+
+#ifndef G_OS_UNIX
+#error This is a Unix-specific test
+#endif
+
+#include <errno.h>
+#include <locale.h>
+#include <glib/gstdio.h>
+#include <gio/gio.h>
+#include <gio/gunixmounts.h>
+
+static void
+test_is_system_fs_type (void)
+{
+  g_assert_true (g_unix_is_system_fs_type ("tmpfs"));
+  g_assert_false (g_unix_is_system_fs_type ("ext4"));
+}
+
+static void
+test_is_system_device_path (void)
+{
+  g_assert_true (g_unix_is_system_device_path ("devpts"));
+  g_assert_false (g_unix_is_system_device_path ("/"));
+}
+
+int
+main (int   argc,
+      char *argv[])
+{
+  setlocale (LC_ALL, "");
+
+  g_test_init (&argc, &argv, NULL);
+
+  g_test_add_func ("/unix-mounts/is-system-fs-type", test_is_system_fs_type);
+  g_test_add_func ("/unix-mounts/is-system-device-path", test_is_system_device_path);
+
+  return g_test_run ();
+}