Citadel changes to Mutter

src/core/util.c

@@ -730,3 +730,51 @@ meta_get_debug_paint_flags (void)
 {
   return debug_paint_flags;
 }
+
+static GFileInfo *
+pid_namespace_file_info (pid_t pid)
+{
+  char *filename = g_strdup_printf("/proc/%u/ns/pid", pid);
+  GFile *file = g_file_new_for_path(filename);
+  g_free(filename);
+
+  GError *error = NULL;
+
+  GFileInfo *info = g_file_query_info(file,
+                                      G_FILE_ATTRIBUTE_STANDARD_IS_SYMLINK "," G_FILE_ATTRIBUTE_STANDARD_SYMLINK_TARGET,
+                                      G_FILE_QUERY_INFO_NOFOLLOW_SYMLINKS,
+                                      NULL,
+                                      &error);
+
+  g_object_unref(file);
+
+  if (info == NULL) {
+    g_warning("MetaWindow: Error attempting to read /proc/%u/ns/pid symlink:  %s", pid, error->message);
+    g_error_free (error);
+    return NULL;
+  }
+
+  if (!g_file_info_get_is_symlink (info)) {
+    g_warning("MetaWindow: /proc/%u/ns/pid exists but is not a symlink?", pid);
+    g_object_unref (info);
+    return NULL;
+  }
+
+  return info;
+
+}
+
+char *
+meta_read_pid_namespace (pid_t pid)
+{
+  char *value = NULL;
+  GFileInfo *info = pid_namespace_file_info (pid);
+  const char *target = g_file_info_get_symlink_target (info);
+
+  if (target) {
+    value = g_strdup (target);
+  }
+  g_object_unref (info);
+
+  return value;
+}