From f792e4499d46337b2704f6a0592c9a9d267a0376 Mon Sep 17 00:00:00 2001
From: Simon McVittie <smcv@collabora.com>
Date: Tue, 12 Dec 2017 14:04:04 +0000
Subject: [PATCH 5/9] _dbus_message_remove_unknown_fields: Add

Signed-off-by: Simon McVittie <smcv@collabora.com>

---

Remove some useless/incorrect code
---
 dbus/dbus-marshal-header.c   | 49 ++++++++++++++++++++++++++++++++++++++++++++
 dbus/dbus-marshal-header.h   |  3 +--
 dbus/dbus-message-internal.h |  2 ++
 dbus/dbus-message.c          | 12 +++++++++++
 4 files changed, 64 insertions(+), 2 deletions(-)

diff --git a/dbus/dbus-marshal-header.c b/dbus/dbus-marshal-header.c
index a3d73f89..d324fb17 100644
--- a/dbus/dbus-marshal-header.c
+++ b/dbus/dbus-marshal-header.c
@@ -1514,4 +1514,53 @@ _dbus_header_byteswap (DBusHeader *header,
   _dbus_string_set_byte (&header->data, BYTE_ORDER_OFFSET, new_order);
 }
 
+/**
+ * Remove every header field not known to this version of dbus.
+ *
+ * @param header the header
+ * @returns #FALSE if no memory
+ */
+dbus_bool_t
+_dbus_header_remove_unknown_fields (DBusHeader *header)
+{
+  DBusTypeReader array;
+  DBusTypeReader fields_reader;
+
+  _dbus_type_reader_init (&fields_reader,
+                          _dbus_header_get_byte_order (header),
+                          &_dbus_header_signature_str,
+                          FIELDS_ARRAY_SIGNATURE_OFFSET,
+                          &header->data,
+                          FIELDS_ARRAY_LENGTH_OFFSET);
+
+  _dbus_type_reader_recurse (&fields_reader, &array);
+
+  while (_dbus_type_reader_get_current_type (&array) != DBUS_TYPE_INVALID)
+    {
+      DBusTypeReader sub;
+      unsigned char field_code;
+
+      _dbus_type_reader_recurse (&array, &sub);
+
+      _dbus_assert (_dbus_type_reader_get_current_type (&sub) == DBUS_TYPE_BYTE);
+      _dbus_type_reader_read_basic (&sub, &field_code);
+
+      if (field_code > DBUS_HEADER_FIELD_LAST)
+        {
+          if (!reserve_header_padding (header))
+            return FALSE;
+
+          if (!_dbus_type_reader_delete (&array, &fields_reader))
+            return FALSE;
+
+          correct_header_padding (header);
+          _dbus_header_cache_invalidate_all (header);
+        }
+
+      _dbus_type_reader_next (&array);
+    }
+
+  return TRUE;
+}
+
 /** @} */
diff --git a/dbus/dbus-marshal-header.h b/dbus/dbus-marshal-header.h
index 85547efd..b838e039 100644
--- a/dbus/dbus-marshal-header.h
+++ b/dbus/dbus-marshal-header.h
@@ -172,7 +172,6 @@ void          _dbus_header_byteswap               (DBusHeader        *header,
                                                    int                new_order);
 DBUS_PRIVATE_EXPORT
 char          _dbus_header_get_byte_order         (const DBusHeader  *header);
-
-
+dbus_bool_t   _dbus_header_remove_unknown_fields  (DBusHeader        *header);
 
 #endif /* DBUS_MARSHAL_HEADER_H */
diff --git a/dbus/dbus-message-internal.h b/dbus/dbus-message-internal.h
index 38c79236..3dcd5621 100644
--- a/dbus/dbus-message-internal.h
+++ b/dbus/dbus-message-internal.h
@@ -64,6 +64,8 @@ void        _dbus_message_add_counter_link      (DBusMessage  *message,
                                                  DBusList     *link);
 void        _dbus_message_remove_counter        (DBusMessage  *message,
                                                  DBusCounter  *counter);
+DBUS_PRIVATE_EXPORT
+dbus_bool_t _dbus_message_remove_unknown_fields (DBusMessage  *message);
 
 DBUS_PRIVATE_EXPORT
 DBusMessageLoader* _dbus_message_loader_new                   (void);
diff --git a/dbus/dbus-message.c b/dbus/dbus-message.c
index 66a39747..36066848 100644
--- a/dbus/dbus-message.c
+++ b/dbus/dbus-message.c
@@ -262,6 +262,18 @@ void _dbus_message_get_unix_fds(DBusMessage *message,
 #endif
 }
 
+/**
+ * Remove every header field not known to this version of dbus.
+ *
+ * @param message the message
+ * @returns #FALSE if no memory
+ */
+dbus_bool_t
+_dbus_message_remove_unknown_fields (DBusMessage *message)
+{
+  return _dbus_header_remove_unknown_fields (&message->header);
+}
+
 /**
  * Sets the serial number of a message.
  * This can only be done once on a message.
-- 
2.15.1