open_toontown_panda3d/dtool/src/prc/configVariableFilename.cxx

47 lines
1.5 KiB
C++

/**
* 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."
*
* @file configVariableFilename.cxx
* @author drose
* @date 2004-11-22
*/
#include "configVariableFilename.h"
#include "executionEnvironment.h"
/**
* Recopies the config variable into the Filename for returning its value.
*/
void ConfigVariableFilename::
reload_cache() {
// NB. MSVC doesn't guarantee that this mutex is initialized in a
// thread-safe manner. But chances are that the first time this is called
// is at static init time, when there is no risk of data races.
static MutexImpl lock;
lock.lock();
// We check again for cache validity since another thread may have beaten
// us to the punch while we were waiting for the lock.
if (!is_cache_valid(_local_modified)) {
nassertv(_core != nullptr);
const ConfigDeclaration *decl = _core->get_declaration(0);
const ConfigPage *page = decl->get_page();
Filename page_filename(page->get_name());
Filename page_dirname = page_filename.get_dirname();
ExecutionEnvironment::shadow_environment_variable("THIS_PRC_DIR", page_dirname.to_os_specific());
_cache = Filename::expand_from(decl->get_string_value());
ExecutionEnvironment::clear_shadow("THIS_PRC_DIR");
mark_cache_valid(_local_modified);
}
lock.unlock();
}