genode/repos/base/include/root/root.h
Norman Feske 4d442bca30 Streamline exception types
This patch reduces the number of exception types by facilitating
globally defined exceptions for common usage patterns shared by most
services. In particular, RPC functions that demand a session-resource
upgrade not longer reflect this condition via a session-specific
exception but via the 'Out_of_ram' or 'Out_of_caps' types.

Furthermore, the 'Parent::Service_denied', 'Parent::Unavailable',
'Root::Invalid_args', 'Root::Unavailable', 'Service::Invalid_args',
'Service::Unavailable', and 'Local_service::Factory::Denied' types have
been replaced by the single 'Service_denied' exception type defined in
'session/session.h'.

This consolidation eases the error handling (there are fewer exceptions
to handle), alleviates the need to convert exceptions along the
session-creation call chain, and avoids possible aliasing problems
(catching the wrong type with the same name but living in a different
scope).
2017-05-31 13:16:07 +02:00

91 lines
2.1 KiB
C++

/*
* \brief Root interface
* \author Norman Feske
* \date 2006-05-11
*/
/*
* Copyright (C) 2006-2017 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 _INCLUDE__ROOT__ROOT_H_
#define _INCLUDE__ROOT__ROOT_H_
#include <base/exception.h>
#include <base/rpc.h>
#include <base/rpc_args.h>
#include <base/affinity.h>
#include <session/capability.h>
namespace Genode {
struct Root;
template <typename> struct Typed_root;
}
struct Genode::Root
{
typedef Rpc_in_buffer<160> Session_args;
typedef Rpc_in_buffer<160> Upgrade_args;
virtual ~Root() { }
/**
* Create session
*
* \throw Insufficient_ram_quota
* \throw Insufficient_cap_quota
* \throw Service_denied
*
* \return capability to new session
*/
virtual Session_capability session(Session_args const &args,
Affinity const &affinity) = 0;
/**
* Extend resource donation to an existing session
*/
virtual void upgrade(Session_capability session, Upgrade_args const &args) = 0;
/**
* Close session
*/
virtual void close(Session_capability session) = 0;
/*********************
** RPC declaration **
*********************/
GENODE_RPC_THROW(Rpc_session, Session_capability, session,
GENODE_TYPE_LIST(Service_denied, Insufficient_ram_quota,
Insufficient_cap_quota),
Session_args const &, Affinity const &);
GENODE_RPC(Rpc_upgrade, void, upgrade,
Session_capability, Upgrade_args const &);
GENODE_RPC(Rpc_close, void, close, Session_capability);
GENODE_RPC_INTERFACE(Rpc_session, Rpc_upgrade, Rpc_close);
};
/**
* Root interface supplemented with information about the managed
* session type
*
* This class template is used to automatically propagate the
* correct session type to 'Parent::announce()' when announcing
* a service.
*/
template <typename SESSION_TYPE>
struct Genode::Typed_root : Root
{
typedef SESSION_TYPE Session_type;
};
#endif /* _INCLUDE__ROOT__ROOT_H_ */