// -*- C++ -*-
/*****************************************************************************\
 * Copyright (c) 2004 Mark Aylett <mark@emantic.co.uk>                       *
 *                                                                           *
 * Permission is hereby granted, free of charge, to any person obtaining a   *
 * copy of this software and associated documentation files (the             *
 * "Software"), to deal in the Software without restriction, including       *
 * without limitation the rights to use, copy, modify, merge, publish,       *
 * distribute, sublicense, and/or sell copies of the Software, and to permit *
 * persons to whom the Software is furnished to do so, subject to the        *
 * following conditions:                                                     *
 *                                                                           *
 * The above copyright notice and this permission notice shall be included   *
 * in all copies or substantial portions of the Software.                    *
 *                                                                           *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS   *
 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF                *
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN *
 * NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,  *
 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR     *
 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE *
 * USE OR OTHER DEALINGS IN THE SOFTWARE.                                    *
\*****************************************************************************/

/**
 * \file mar_transaction_cpp.h
 * \brief TODO
 */

#ifndef INCLUDED_MAR_TRANSACTION_CPP
#define INCLUDED_MAR_TRANSACTION_CPP

#ifndef INCLUDED_MAR_UTIL_CPP
#include "mar_util_cpp.h"
#endif // INCLUDED_MAR_UTIL_CPP

#if !defined(WIN32)

#ifndef INCLUDED_CLIMITS
#define INCLUDED_CLIMITS
#include <climits>
#endif // INCLUDED_CLIMITS

#if !defined(PATH_MAX)
#define MAR_MAXPATH 255
#else // PATH_MAX
#define MAR_MAXPATH PATH_MAX
#endif // PATH_MAX

#else // WIN32

#ifndef INCLUDED_CSTDLIB
#define INCLUDED_CSTDLIB
#include <cstdlib>
#endif // INCLUDED_CSTDLIB

#if !defined(_MAX_PATH)
#define MAR_MAXPATH 260
#else // _MAX_PATH
#define MAR_MAXPATH _MAX_PATH
#endif // _MAX_PATH

#endif // WIN32

namespace mar {

    template <typename file_policyT>
    class transaction {

    public:
        typedef file_policyT file_policy_type;
    private:

        char path_[MAR_MAXPATH];
        char master_[MAR_MAXPATH];
        archive ar_;
        bool done_;

        transaction(const transaction& rhs);

        transaction&
        operator =(const transaction& rhs);

    public:
        ~transaction() MAR_NOTHROW
        {
            try {
                close(false);
            }
            catch (...) {
            }
        }
        transaction(const char* path, const char* master)
            : ar_(opencopy(path, master)),
              done_(false)
        {
            strncpy(path_, path, sizeof(path_));
            strncpy(master_, master, sizeof(master_));

            path_[sizeof(path_) - 1] = '\0';
            master_[sizeof(master_) - 1] = '\0';
        }
        void
        close(bool commit = true)
        {
            if (done_)
                return;

            done_ = true;

            int err(0);
            if (ar_.isopen() && -1 == ar_.release())
                err = mar_errno();

            if (commit && 0 == err)
                file_policy_type::rename(path_, master_);
            else
                file_policy_type::unlink(path_);

            if (err)
                throw error(err);
        }
        void
        commit()
        {
            close(true);
        }
        void
        rollback()
        {
            close(false);
        }
        archive
        retain()
        {
            return ar_;
        }
        const archive&
        retain() const
        {
            return ar_;
        }
    };
}

#endif // INCLUDED_MAR_TRANSACTION_CPP