Merge branch '1400-g_file_attribute_unix_is_mountpoint-is-false-for-root' into 'master'

Resolve "G_FILE_ATTRIBUTE_UNIX_IS_MOUNTPOINT is False for /"

Closes #1400

See merge request GNOME/glib!51

gio/gfileinfo.h

@@ -644,7 +644,8 @@ typedef struct _GFileInfoClass   GFileInfoClass;
  *
  * A key in the "unix" namespace for checking if the file represents a
  * UNIX mount point. This attribute is %TRUE if the file is a UNIX mount
- * point. This attribute is only available for UNIX file systems.
+ * point. Since 2.58, `/` is considered to be a mount point.
+ * This attribute is only available for UNIX file systems.
  * Corresponding #GFileAttributeType is %G_FILE_ATTRIBUTE_TYPE_BOOLEAN.
  **/
 #define G_FILE_ATTRIBUTE_UNIX_IS_MOUNTPOINT "unix::is-mountpoint" /* boolean */

gio/glocalfileinfo.c

@@ -821,6 +821,7 @@ _g_local_file_info_get_parent_info (const char            *dir,
   parent_info->is_sticky = FALSE;
   parent_info->has_trash_dir = FALSE;
   parent_info->device = 0;
+  parent_info->inode = 0;
 
   if (_g_file_attribute_matcher_matches_id (attribute_matcher, G_FILE_ATTRIBUTE_ID_ACCESS_CAN_RENAME) ||
       _g_file_attribute_matcher_matches_id (attribute_matcher, G_FILE_ATTRIBUTE_ID_ACCESS_CAN_DELETE) ||
@@ -850,6 +851,7 @@ _g_local_file_info_get_parent_info (const char            *dir,
 #endif
 	  parent_info->owner = statbuf.st_uid;
 	  parent_info->device = statbuf.st_dev;
+	  parent_info->inode = statbuf.st_ino;
           /* No need to find trash dir if it's not writable anyway */
           if (parent_info->writable &&
               _g_file_attribute_matcher_matches_id (attribute_matcher, G_FILE_ATTRIBUTE_ID_ACCESS_CAN_TRASH))
@@ -1965,7 +1967,7 @@ _g_local_file_info_get (const char             *basename,
 
   if (stat_ok && parent_info && parent_info->device != 0 &&
       _g_file_attribute_matcher_matches_id (attribute_matcher, G_FILE_ATTRIBUTE_ID_UNIX_IS_MOUNTPOINT) &&
-      statbuf.st_dev != parent_info->device) 
+      (statbuf.st_dev != parent_info->device || statbuf.st_ino == parent_info->inode))
     _g_file_info_set_attribute_boolean_by_id (info, G_FILE_ATTRIBUTE_ID_UNIX_IS_MOUNTPOINT, TRUE);
   
   if (stat_ok)

gio/glocalfileinfo.h

@@ -36,6 +36,7 @@ typedef struct
   gboolean has_trash_dir;
   int      owner;
   dev_t    device;
+  ino_t    inode;
   gpointer extra_data;
   GDestroyNotify free_extra_data;
 } GLocalParentFileInfo;

gio/tests/live-g-file.c

@@ -417,6 +417,15 @@ test_attributes (struct StructureItem item, GFileInfo * info)
 					   G_FILE_ATTRIBUTE_STANDARD_IS_HIDDEN);
       g_assert_cmpint (is_hidden, ==, TRUE);
     }
+
+  /* unix::is-mountpoint */
+  if (posix_compat)
+    {
+      gboolean is_mountpoint =
+        g_file_info_get_attribute_boolean (info,
+                                      G_FILE_ATTRIBUTE_UNIX_IS_MOUNTPOINT);
+      g_assert_false (is_mountpoint);
+    }
 }
 
 static void
@@ -853,6 +862,33 @@ test_copy_move (gconstpointer test_data)
   g_object_unref (root);
 }
 
+/* Test that G_FILE_ATTRIBUTE_UNIX_IS_MOUNTPOINT is TRUE for / and for another
+ * known mountpoint. The FALSE case is tested for many directories and files by
+ * test_initial_structure(), via test_attributes().
+ */
+static void
+test_unix_is_mountpoint (gconstpointer data)
+{
+  const gchar *path = data;
+  GFile *file = g_file_new_for_path (path);
+  GFileInfo *info;
+  gboolean is_mountpoint;
+  GError *error = NULL;
+
+  info = g_file_query_info (file, G_FILE_ATTRIBUTE_UNIX_IS_MOUNTPOINT,
+                            G_FILE_QUERY_INFO_NONE, NULL, &error);
+  g_assert_no_error (error);
+  g_assert_nonnull (info);
+
+  is_mountpoint =
+    g_file_info_get_attribute_boolean (info,
+                                       G_FILE_ATTRIBUTE_UNIX_IS_MOUNTPOINT);
+  g_assert_true (is_mountpoint);
+
+  g_clear_object (&info);
+  g_clear_object (&file);
+}
+
 static void
 test_create (gconstpointer test_data)
 {
@@ -1342,6 +1378,18 @@ main (int argc, char *argv[])
   if (!only_create_struct)
     g_test_add_data_func ("/live-g-file/test_open", target_path, test_open);
 
+  if (posix_compat)
+    {
+      g_test_add_data_func ("/live-g-file/test_unix_is_mountpoint/sysroot",
+                            "/",
+                            test_unix_is_mountpoint);
+#ifdef __linux__
+      g_test_add_data_func ("/live-g-file/test_unix_is_mountpoint/proc",
+                            "/proc",
+                            test_unix_is_mountpoint);
+#endif
+    }
+
   /*  Write test - create  */
   if (write_test && (!only_create_struct))
     g_test_add_data_func ("/live-g-file/test_create", target_path,