open_toontown_panda3d/panda/src/putil/copyOnWriteObject.cxx

44 lines
1.5 KiB
C++

// Filename: copyOnWriteObject.cxx
// Created by: drose (09Apr07)
//
////////////////////////////////////////////////////////////////////
//
// PANDA 3D SOFTWARE
// Copyright (c) Carnegie Mellon University. All rights reserved.
//
// All use of this software is subject to the terms of the revised BSD
// license. You should have received a copy of this license along
// with this source code in a file named "LICENSE."
//
////////////////////////////////////////////////////////////////////
#include "copyOnWriteObject.h"
#include "mutexHolder.h"
#include "pnotify.h"
TypeHandle CopyOnWriteObject::_type_handle;
#ifdef COW_THREADED
////////////////////////////////////////////////////////////////////
// Function: CopyOnWriteObject::unref
// Access: Public, Virtual
// Description: Explicitly decrements the reference count. See
// ReferenceCount::unref().
//
// In the case of a CopyOnWriteObject, when the
// reference count decrements down to the cache
// reference count, the object is implicitly unlocked.
////////////////////////////////////////////////////////////////////
bool CopyOnWriteObject::
unref() const {
MutexHolder holder(_lock_mutex);
bool is_zero = CachedTypedWritableReferenceCount::unref();
if (get_ref_count() == get_cache_ref_count()) {
((CopyOnWriteObject *)this)->_lock_status = LS_unlocked;
((CopyOnWriteObject *)this)->_locking_thread = NULL;
((CopyOnWriteObject *)this)->_lock_cvar.notify();
}
return is_zero;
}
#endif // COW_THREADED