mirror of
https://github.com/genodelabs/genode.git
synced 2024-12-21 06:33:31 +00:00
366913c146
Removed the modified mark from handles that have been written to when they are synced, otherwise a notification would be sent again when the handle is closed. Ref #2839
117 lines
2.8 KiB
C++
117 lines
2.8 KiB
C++
/*
|
|
* \brief Representation of an open file system node within the component
|
|
* \author Christian Prochaska
|
|
* \date 2017-06-09
|
|
*/
|
|
|
|
/*
|
|
* Copyright (C) 2017 Genode Labs GmbH
|
|
*
|
|
* This file is part of the Genode OS framework, which is distributed
|
|
* under the terms of the GNU Affero General Public License version 3.
|
|
*/
|
|
|
|
#ifndef _OPEN_NODE_H_
|
|
#define _OPEN_NODE_H_
|
|
|
|
/* Genode includes */
|
|
#include <file_system/listener.h>
|
|
#include <file_system_session/file_system_session.h>
|
|
|
|
namespace File_system {
|
|
/*
|
|
* \param NODE component-specific node type
|
|
*/
|
|
template <typename NODE> class Open_node;
|
|
}
|
|
|
|
template <typename NODE>
|
|
class File_system::Open_node : public File_system::Node
|
|
{
|
|
private:
|
|
|
|
Genode::Id_space<File_system::Node>::Element _element;
|
|
|
|
Genode::Weak_ptr<NODE> _node;
|
|
Genode::Constructible<File_system::Listener> _listener { };
|
|
|
|
Listener::Version const _version_when_opened { _node_version(_node) };
|
|
|
|
/*
|
|
* Flag to track whether the underlying file-system node was
|
|
* modified via this 'Open_node'. That is, if closing the 'Open_node'
|
|
* should notify listeners of the file.
|
|
*/
|
|
bool _was_written = false;
|
|
|
|
static Listener::Version const _node_version(Genode::Weak_ptr<NODE> node)
|
|
{
|
|
Genode::Locked_ptr<NODE> locked_node { node };
|
|
|
|
if (locked_node.valid())
|
|
return locked_node->curr_version();
|
|
else
|
|
return Listener::Version { 0 };
|
|
}
|
|
|
|
public:
|
|
|
|
Open_node(Genode::Weak_ptr<NODE> node,
|
|
Genode::Id_space<File_system::Node> &id_space)
|
|
: _element(*this, id_space), _node(node) { }
|
|
|
|
~Open_node()
|
|
{
|
|
Genode::Locked_ptr<NODE> node { _node };
|
|
|
|
if (_listener.constructed()) {
|
|
if (node.valid())
|
|
node->remove_listener(&*_listener);
|
|
_listener.destruct();
|
|
}
|
|
|
|
/*
|
|
* Notify remaining listeners about the changed file
|
|
*/
|
|
if (_was_written && node.valid()) {
|
|
node->notify_listeners();
|
|
}
|
|
}
|
|
|
|
Genode::Weak_ptr<NODE>&node() { return _node; }
|
|
File_system::Listener &listener() { return *_listener; }
|
|
|
|
Genode::Id_space<File_system::Node>::Id id() { return _element.id(); }
|
|
|
|
/**
|
|
* Register packet stream sink to be notified of node changes
|
|
*/
|
|
void register_notify(File_system::Sink &sink)
|
|
{
|
|
Genode::Locked_ptr<NODE> node { _node };
|
|
|
|
/*
|
|
* If there was already a handler registered for the node,
|
|
* remove the old handler.
|
|
*/
|
|
if (_listener.constructed()) {
|
|
if (node.valid())
|
|
node->remove_listener(&*_listener);
|
|
_listener.destruct();
|
|
}
|
|
|
|
/*
|
|
* Register new handler
|
|
*/
|
|
if (node.valid()) {
|
|
_listener.construct(sink, id(), _version_when_opened);
|
|
node->add_listener(&*_listener);
|
|
}
|
|
}
|
|
|
|
void mark_as_written() { _was_written = true; }
|
|
void unmark_as_written() { _was_written = false; }
|
|
};
|
|
|
|
#endif /* _OPEN_NODE_H_ */
|