previouslySerialized
Checks whether the object has already been serialized into the XML stream, emitting a reference if it has.
Declaration
virtual bool previouslySerialized(
const OSMetaClassBase *object);Parameters
- object:
The object to check.
Return Value
true if object has already been serialized by this OSSerialize object and a reference to it is successfully added to the XML stream, false otherwise.
Overview
This function both reduces the size of generated XML by emitting shorter references to existing objects with the same value (particularly for OSString, OSSymbol, and OSData), and also preserves instance references so that the user-space I/O Kit library can reconstruct an identical graph of object relationships.
All classes that override OSObject::serialize. should call this function before doing any actual serialization; if it returns true, the serialize implementation can immediately return true.