src/object.cpp

/*
 *
 *  D-Bus++ - C++ bindings for D-Bus
 *
 *  Copyright (C) 2005-2007  Paolo Durante <shackan@gmail.com>
 *
 *
 *  This library is free software; you can redistribute it and/or
 *  modify it under the terms of the GNU Lesser General Public
 *  License as published by the Free Software Foundation; either
 *  version 2.1 of the License, or (at your option) any later version.
 *
 *  This library is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 *  Lesser General Public License for more details.
 *
 *  You should have received a copy of the GNU Lesser General Public
 *  License along with this library; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 */

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

#include <dbus-c++/debug.h>
#include <dbus-c++/object.h>
#include "internalerror.h"

#include <cstring>
#include <map>
#include <dbus/dbus.h>

#include "message_p.h"
#include "server_p.h"
#include "connection_p.h"

using namespace DBus;

Object::Object(Connection &conn, const Path &path, const char *service)
: _conn(conn), _path(path), _service(service ? service : "")
{
}

Object::~Object()
{
}

struct ObjectAdaptor::Private
{
	static void unregister_function_stub(DBusConnection *, void *);
	static DBusHandlerResult message_function_stub(DBusConnection *, DBusMessage *, void *);
};

static DBusObjectPathVTable _vtable =
{
	ObjectAdaptor::Private::unregister_function_stub,
	ObjectAdaptor::Private::message_function_stub,
	NULL, NULL, NULL, NULL
};

void ObjectAdaptor::Private::unregister_function_stub(DBusConnection *conn, void *data)
{
 	//TODO: what do we have to do here ?
}

DBusHandlerResult ObjectAdaptor::Private::message_function_stub(DBusConnection *, DBusMessage *dmsg, void *data)
{
	ObjectAdaptor *o = static_cast<ObjectAdaptor *>(data);

	if (o)
	{
		Message msg(new Message::Private(dmsg));

		debug_log("in object %s", o->path().c_str());
		debug_log(" got message #%d from %s to %s",
			msg.serial(),
			msg.sender(),
			msg.destination()
		);

		return o->handle_message(msg)
			? DBUS_HANDLER_RESULT_HANDLED
			: DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
	}
	else
	{
		return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
	}
}

typedef std::map<Path, ObjectAdaptor *> ObjectAdaptorTable;
static ObjectAdaptorTable _adaptor_table;

ObjectAdaptor *ObjectAdaptor::from_path(const Path &path)
{
	ObjectAdaptorTable::iterator ati = _adaptor_table.find(path);

	if (ati != _adaptor_table.end())
		return ati->second;

	return NULL;
}

ObjectAdaptorPList ObjectAdaptor::from_path_prefix(const std::string &prefix)
{
	ObjectAdaptorPList ali;

	ObjectAdaptorTable::iterator ati = _adaptor_table.begin();

	size_t plen = prefix.length();

	while (ati != _adaptor_table.end())
	{
		if (!strncmp(ati->second->path().c_str(), prefix.c_str(), plen))
			ali.push_back(ati->second);

		++ati;
	}

	return ali;
}

ObjectPathList ObjectAdaptor::child_nodes_from_prefix(const std::string &prefix)
{
	ObjectPathList ali;

	ObjectAdaptorTable::iterator ati = _adaptor_table.begin();

	size_t plen = prefix.length();

	while (ati != _adaptor_table.end())
	{
	  if (ati->second->path() != "/" &&  // Root node is never a child.
	      !strncmp(ati->second->path().c_str(), prefix.c_str(), plen))
		{
				std::string p = ati->second->path().substr(plen);
				p = p.substr(0,p.find('/'));
				ali.push_back(p);
		}
		++ati;
	}

	ali.sort();
	ali.unique();

	return ali;
}

ObjectAdaptor::ObjectAdaptor(Connection &conn, const Path &path)
: Object(conn, path, conn.unique_name()), _eflag(USE_EXCEPTIONS)
{
	register_obj();
}

ObjectAdaptor::ObjectAdaptor(Connection &conn, const Path &path, registration_time rtime)
: Object(conn, path, conn.unique_name()), _eflag(USE_EXCEPTIONS)
{
	if (rtime == REGISTER_NOW)
		register_obj();
}

ObjectAdaptor::ObjectAdaptor(Connection &conn, const Path &path, registration_time rtime,
				exceptions_flag eflag)
: Object(conn, path, conn.unique_name()), _eflag(eflag)
{
	if (rtime == REGISTER_NOW)
		register_obj();
}

ObjectAdaptor::~ObjectAdaptor()
{
	unregister_obj();
}

void ObjectAdaptor::register_obj()
{
	debug_log("registering local object %s", path().c_str());

        if (conn()._pvt->conn == NULL)
        {
                throw ErrorInvalidArgs("NULL connection");
        }
        else if (path().c_str() == NULL)
        {
                throw ErrorInvalidArgs("NULL path");
        }
        else if (path().c_str()[0] != '/')
        {
                std::string message = "Path must start with '/': " + path();
                throw ErrorInvalidArgs(message.c_str());
        }

	DBusError error = DBUS_ERROR_INIT;
	if (!dbus_connection_try_register_object_path(conn()._pvt->conn, path().c_str(), &_vtable, this, &error))
	{
		if (dbus_error_has_name(&error, DBUS_ERROR_OBJECT_PATH_IN_USE))
		{
			dbus_error_free(&error);
			throw ErrorObjectPathInUse("unable to register object path");
		}
		else
		{
			dbus_error_free(&error);
			throw ErrorNoMemory("unable to register object path");
		}
	}

	_adaptor_table[path()] = this;
}

void ObjectAdaptor::unregister_obj()
{
	if (!is_registered())
		return;

	_adaptor_table.erase(path());

	debug_log("unregistering local object %s", path().c_str());

        if (conn()._pvt->conn == NULL)
        {
                throw ErrorInvalidArgs("NULL connection");
        }
        else if (path().c_str() == NULL)
        {
                throw ErrorInvalidArgs("NULL path");
        }
        else if (path().c_str()[0] != '/')
        {
                std::string message = "Path must start with '/': " + path();
                throw ErrorInvalidArgs(message.c_str());
        }

	dbus_connection_unregister_object_path(conn()._pvt->conn, path().c_str());
}

bool ObjectAdaptor::is_registered()
{
	return _adaptor_table.find(path()) != _adaptor_table.end();
}

void ObjectAdaptor::_emit_signal(SignalMessage &sig)
{
	sig.path(path().c_str());

	conn().send(sig);
}

struct ReturnLaterError
{
	const Tag *tag;
};

bool ObjectAdaptor::handle_message(const Message &msg)
{
	switch (msg.type())
	{
		case DBUS_MESSAGE_TYPE_METHOD_CALL:
		{
			const CallMessage &cmsg = reinterpret_cast<const CallMessage &>(msg);
			const char *member      = cmsg.member();
			const char *interface   = cmsg.interface();

			debug_log(" invoking method %s.%s", interface, member);

			InterfaceAdaptor *ii = find_interface(interface);
			if (ii)
			{
				if (_eflag == AVOID_EXCEPTIONS) {
					Message ret = ii->dispatch_method(cmsg);
					Tag *tag = ret.tag();
					if (tag) {
						_continuations[tag] =
						    new Continuation(conn(), cmsg, tag);
					} else {
						conn().send(ret);
					}
					return true;
				}
				// TODO(jglasgow@google.com): make this code
				// conditional based on compile time option to
				// support exceptions.
				try
				{
					Message ret = ii->dispatch_method(cmsg);
					conn().send(ret);
				}
				catch(Error &e)
				{
					ErrorMessage em(cmsg, e.name(), e.message());
					conn().send(em);
				}
				catch(ReturnLaterError &rle)
				{
					_continuations[rle.tag] = new Continuation(conn(), cmsg, rle.tag);
				}
				return true;
			}
			else
			{
				return false;
			}
		}
		default:
		{
			return false;
		}
	}
}

void ObjectAdaptor::return_later(const Tag *tag)
{
	ReturnLaterError rle = { tag };
	throw rle;
}

void ObjectAdaptor::return_now(Continuation *ret)
{
	ret->_conn.send(ret->_return);

	ContinuationMap::iterator di = _continuations.find(ret->_tag);

	delete di->second;

	_continuations.erase(di);
}

void ObjectAdaptor::return_error(Continuation *ret, const Error error)
{
	ret->_conn.send(ErrorMessage(ret->_call, error.name(), error.message()));

	ContinuationMap::iterator di = _continuations.find(ret->_tag);

	delete di->second;

	_continuations.erase(di);
}

ObjectAdaptor::Continuation *ObjectAdaptor::find_continuation(const Tag *tag)
{
	ContinuationMap::iterator di = _continuations.find(tag);

	return di != _continuations.end() ? di->second : NULL;
}

ObjectAdaptor::Continuation::Continuation(Connection &conn, const CallMessage &call, const Tag *tag)
: _conn(conn), _call(call), _return(_call), _tag(tag)
{
	_writer = _return.writer(); //todo: verify
}

/*
*/

ObjectProxy::ObjectProxy(Connection &conn, const Path &path, const char *service)
: Object(conn, path, service)
{
	register_obj();
}

// TODO(ers@google.com): unregister_obj() makes a synchronous
// dbus method call, which can result in a deadlock if the
// ObjectProxy is deleted while in a callback from a signal
// or a pending call reply.
ObjectProxy::~ObjectProxy()
{
	cancel_pending_calls();
	unregister_obj();
}

void ObjectProxy::cancel_pending_calls()
{
	PendingCallList::const_iterator pi = _pending_calls.begin();
	while (pi != _pending_calls.end())
	{
		(*pi)->cancel();
		delete *pi;
		++pi;
	}
	_pending_calls.clear();
}

void ObjectProxy::_remove_pending_call(PendingCall *pending)
{
	PendingCallList::iterator pi = _pending_calls.begin();
	while (pi != _pending_calls.end())
	{
		if (*pi == pending)
		{
			_pending_calls.erase(pi);
			break;
		}
		++pi;
	}
	delete pending;
}

void ObjectProxy::register_obj()
{
	debug_log("registering remote object %s", path().c_str());

	_filtered = new Callback<ObjectProxy, bool, const Message &>(this, &ObjectProxy::handle_message);

	conn().add_filter(_filtered);

	InterfaceProxyTable::const_iterator ii = _interfaces.begin();
	while (ii != _interfaces.end())
	{
		std::string im = "type='signal',interface='"+ii->first+"',path='"+path()+"'";
		conn().add_match(im.c_str());
		++ii;
	}
}

void ObjectProxy::unregister_obj()
{
	debug_log("unregistering remote object %s", path().c_str());

	InterfaceProxyTable::const_iterator ii = _interfaces.begin();
	while (ii != _interfaces.end())
	{
		std::string im = "type='signal',interface='"+ii->first+"',path='"+path()+"'";
		conn().remove_match(im.c_str());
		++ii;
	}
	conn().remove_filter(_filtered);
}

bool ObjectProxy::is_registered()
{
	return true;
}

Message ObjectProxy::_invoke_method(CallMessage &call)
{
	if (call.path() == NULL)
		call.path(path().c_str());

	if (call.destination() == NULL)
		call.destination(service().c_str());

	return conn().send_blocking(call);
}

bool ObjectProxy::_invoke_method_noreply(CallMessage &call)
{
	if (call.path() == NULL)
		call.path(path().c_str());

	if (call.destination() == NULL)
		call.destination(service().c_str());

	return conn().send(call);
}

PendingCall *ObjectProxy::_invoke_method_async(CallMessage &call, int timeout)
{
	if (call.path() == NULL)
		call.path(path().c_str());

	if (call.destination() == NULL)
		call.destination(service().c_str());

	PendingCall *pending = conn().send_async(call, timeout);
	_pending_calls.push_back(pending);
	return pending;
}

bool ObjectProxy::handle_message(const Message &msg)
{
	switch (msg.type())
	{
		case DBUS_MESSAGE_TYPE_SIGNAL:
		{
			const SignalMessage &smsg = reinterpret_cast<const SignalMessage &>(msg);
			const char *interface	= smsg.interface();
			const char *member	= smsg.member();
			const char *objpath	= smsg.path();

			if (objpath != path()) return false;

			debug_log("filtered signal %s(in %s) from %s to object %s",
				member, interface, msg.sender(), objpath);

			InterfaceProxy *ii = find_interface(interface);
			if (ii)
			{
				return ii->dispatch_signal(smsg);
			}
			else
			{
				return false;
			}
		}
		default:
		{
			return false;
		}
	}
}