request_interface.h

/***************************************************************************
 *  include/stxxl/bits/io/request_interface.h
 *
 *  Part of the STXXL. See http://stxxl.sourceforge.net
 *
 *  Copyright (C) 2002 Roman Dementiev <[email protected]>
 *  Copyright (C) 2008, 2009, 2011 Andreas Beckmann <[email protected]>
 *  Copyright (C) 2009 Johannes Singler <[email protected]>
 *
 *  Distributed under the Boost Software License, Version 1.0.
 *  (See accompanying file LICENSE_1_0.txt or copy at
 *  http://www.boost.org/LICENSE_1_0.txt)
 **************************************************************************/

#ifndef STXXL_IO__REQUEST_INTERFACE_H_
#define STXXL_IO__REQUEST_INTERFACE_H_

#include <ostream>

#include <stxxl/bits/namespace.h>
#include <stxxl/bits/noncopyable.h>
#include <stxxl/bits/common/types.h>


__STXXL_BEGIN_NAMESPACE


class onoff_switch;


class request_interface : private noncopyable
{
public:
    typedef stxxl::external_size_type offset_type;
    typedef stxxl::internal_size_type size_type;
    enum request_type { READ, WRITE };

public:
    virtual bool add_waiter(onoff_switch * sw) = 0;
    virtual void delete_waiter(onoff_switch * sw) = 0;

protected:
    virtual void notify_waiters() = 0;

public:
    // HACK!
    virtual void serve() = 0;

protected:
    virtual void completed() = 0;

public:
    virtual void wait(bool measure_time = true) = 0;

    virtual bool cancel() = 0;

    virtual bool poll() = 0;

    virtual const char * io_type() const = 0;

    virtual std::ostream & print(std::ostream & out) const = 0;

    virtual ~request_interface()
    { }
};


__STXXL_END_NAMESPACE

#endif // !STXXL_IO__REQUEST_INTERFACE_H_
// vim: et:ts=4:sw=4