/*
 * \brief  Terminal session interface
 * \author Norman Feske
 * \date   2011-08-11
 */

/*
 * Copyright (C) 2011 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 _INCLUDE__TERMINAL_SESSION__TERMINAL_SESSION_H_
#define _INCLUDE__TERMINAL_SESSION__TERMINAL_SESSION_H_

/* Genode includes */
#include <session/session.h>
#include <base/rpc.h>
#include <dataspace/capability.h>

namespace Terminal {

	struct Session : Genode::Session
	{
		static const char *service_name() { return "Terminal"; }

		class Size
		{
			private:

				unsigned _columns, _lines;

			public:

				Size() : _columns(0), _lines(0) { }

				Size(unsigned columns, unsigned lines)
				: _columns(columns), _lines(lines) { }

				unsigned columns() const { return _columns; }
				unsigned lines()   const { return _lines; }
		};

		/**
		 * Return terminal size
		 */
		virtual Size size() = 0;

		/**
		 * Return true of one or more characters are available for reading
		 */
		virtual bool avail() = 0;

		/**
		 * Read characters from terminal
		 */
		virtual Genode::size_t read(void *buf, Genode::size_t buf_size) = 0;

		/**
		 * Write characters to terminal
		 */
		virtual Genode::size_t write(void const *buf, Genode::size_t num_bytes) = 0;

		/**
		 * Register signal handler to be informed about the established connection
		 *
		 * This function is used for a simple startup protocol of terminal
		 * sessions. At session-creation time, the terminal session may not
		 * be ready to use. For example, a TCP terminal session needs an
		 * established TCP connection first. However, we do not want to let the
		 * session-creation block on the server side because this would render
		 * the servers entrypoint unavailable for all other clients until the
		 * TCP connection is ready. Instead, we deliver a 'connected' signal
		 * to the client emitted when the session becomes ready to use. The
		 * Terminal::Connection waits for this signal at construction time.
		 */
		virtual void connected_sigh(Genode::Signal_context_capability cap) = 0;

		/**
		 * Register signal handler to be informed about ready-to-read characters
		 */
		virtual void read_avail_sigh(Genode::Signal_context_capability cap) = 0;


		/*******************
		 ** RPC interface **
		 *******************/

		GENODE_RPC(Rpc_size, Size, size);
		GENODE_RPC(Rpc_avail, bool, avail);
		GENODE_RPC(Rpc_read, Genode::size_t, _read, Genode::size_t);
		GENODE_RPC(Rpc_write, void, _write, Genode::size_t);
		GENODE_RPC(Rpc_connected_sigh, void, connected_sigh, Genode::Signal_context_capability);
		GENODE_RPC(Rpc_read_avail_sigh, void, read_avail_sigh, Genode::Signal_context_capability);
		GENODE_RPC(Rpc_dataspace, Genode::Dataspace_capability, _dataspace);

		GENODE_RPC_INTERFACE(Rpc_size, Rpc_avail, Rpc_read, Rpc_write,
		                     Rpc_connected_sigh, Rpc_read_avail_sigh,
		                     Rpc_dataspace);
	};
}

#endif /* _INCLUDE__TERMINAL_SESSION__TERMINAL_SESSION_H_ */