genode/dde_rump/src/server/rump_fs/node.h

122 lines
2.2 KiB
C++

/*
* \brief File-system node
* \author Norman Feske
* \author Christian Helmuth
* \author Sebastian Sumpf
* \date 2013-11-11
*/
/*
* Copyright (C) 2013-2014 Genode Labs GmbH
*
* This file is part of the Genode OS framework, which is distributed
* under the terms of the GNU General Public License version 2.
*/
#ifndef _NODE_H_
#define _NODE_H_
/* Genode includes */
#include <util/list.h>
#include <base/signal.h>
namespace File_system {
class Listener;
class Node;
}
class File_system::Listener : public List<Listener>::Element
{
private:
Signal_context_capability _sigh;
bool _marked_as_updated;
public:
Listener() : _marked_as_updated(false) { }
Listener(Signal_context_capability sigh)
: _sigh(sigh), _marked_as_updated(false) { }
void notify()
{
if (_marked_as_updated && _sigh.valid())
Signal_transmitter(_sigh).submit();
_marked_as_updated = false;
}
void mark_as_updated()
{
_marked_as_updated = true;
}
bool valid() const { return _sigh.valid(); }
};
class File_system::Node : public List<Node>::Element
{
public:
typedef char Name[128];
private:
Name _name;
unsigned long const _inode;
List<Listener> _listeners;
public:
Node(unsigned long inode) : _inode(inode) { _name[0] = 0; }
virtual ~Node()
{
/* propagate event to listeners */
mark_as_updated();
notify_listeners();
while (_listeners.first())
_listeners.remove(_listeners.first());
}
unsigned long inode() const { return _inode; }
char const *name() const { return _name; }
/**
* Assign name
*/
void name(char const *name) { strncpy(_name, name, sizeof(_name)); }
virtual size_t read(char *dst, size_t len, seek_off_t) = 0;
virtual size_t write(char const *src, size_t len, seek_off_t) = 0;
void add_listener(Listener *listener)
{
_listeners.insert(listener);
}
void remove_listener(Listener *listener)
{
_listeners.remove(listener);
}
void notify_listeners()
{
for (Listener *curr = _listeners.first(); curr; curr = curr->next())
curr->notify();
}
void mark_as_updated()
{
for (Listener *curr = _listeners.first(); curr; curr = curr->next())
curr->mark_as_updated();
}
};
#endif /* _NODE_H_ */