include/core/serialization.h

/*
 * Copyright © 2010 Sam Spilsbury
 *
 * Permission to use, copy, modify, distribute, and sell this software
 * and its documentation for any purpose is hereby granted without
 * fee, provided that the above copyright notice appear in all copies
 * and that both that copyright notice and this permission notice
 * appear in supporting documentation, and that the name of
 * Dennis Kasprzyk not be used in advertising or publicity pertaining to
 * distribution of the software without specific, written prior permission.
 * Dennis Kasprzyk makes no representations about the suitability of this
 * software for any purpose. It is provided "as is" without express or
 * implied warranty.
 *
 * DENNIS KASPRZYK DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
 * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN
 * NO EVENT SHALL DENNIS KASPRZYK BE LIABLE FOR ANY SPECIAL, INDIRECT OR
 * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS
 * OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT,
 * NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION
 * WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 *
 * Authors: Sam Spilsbury <smspillaz@gmail.com>
 */

#ifndef _COMPSERIALIZATION_H
#define _COMPSERIALIZATION_H

#include <core/core.h>
#include <core/timer.h>
#include <core/propertywriter.h>

#include <typeinfo>
#include <boost/preprocessor/cat.hpp>

#include <boost/archive/text_iarchive.hpp>
#include <boost/archive/text_oarchive.hpp>

#include <boost/serialization/export.hpp>

#include <boost/serialization/list.hpp>
#include <boost/serialization/vector.hpp>

#include <sstream>
#include <fstream>


template <class T>
class PluginStateWriter
{
    private:
        PropertyWriter mPw;
        Window         mResource;
        T              *mClassPtr;
        CompTimer      mTimeout;

        friend class boost::serialization::access;

        bool
        checkTimeout ()
        {
            if (!screen->shouldSerializePlugins ())
                return false;

            CompOption::Vector atomTemplate = mPw.readProperty (mResource);

            if (atomTemplate.empty ())
                return false;

            if (!(atomTemplate.at (0).value ().type () == CompOption::TypeString))
                return false;
            
            std::istringstream iss (atomTemplate.at (0).value ().s ());
            boost::archive::text_iarchive ia (iss);
            
            ia >> *this;

            postLoad ();
            
            /* No need to store this data in XServer anymore, get rid of it */
            
            mPw.deleteProperty (mResource);
            
            return false;
        };          
            
    public:

        template <class Archive>
        void serialize (Archive &ar, const unsigned int version)
        {
             ar & *mClassPtr;;
        };    

        virtual void postLoad () {};
        
        /* Classes get destroyed in the order of:
         * derived -> this. Because variables might
         * have thier destructors called, we provide
         * a method to intercept this process
         * and immediately serialize data such that it
         * won't be unintentionally destroyed before the
         * base CompPluginStateWriter destructor gets called
         */
        
        void writeSerializedData ()
        {
            if (!screen->shouldSerializePlugins ())
                return;

            CompOption::Vector atomTemplate = mPw.getReadTemplate ();     
            std::string str;  
            std::ostringstream oss (str);
            boost::archive::text_oarchive oa (oss);
            
            oa << *this;
            
            CompOption::Value v (oss.str ().c_str ());
            atomTemplate.at (0).set (v);

            mPw.updateProperty (mResource, atomTemplate, XA_STRING);
        }       
        
        PluginStateWriter (T *instance,
                           Window xid) :
            mResource (xid),
            mClassPtr (instance)
        {
            if (screen->shouldSerializePlugins ())

            {
                CompString atomName = compPrintf ("_COMPIZ_%s_STATE",
                                                  typeid (T).name ());
                CompOption::Vector o;

                o.resize (1);
                o.at (0).setName ("data", CompOption::TypeString);

                mPw = PropertyWriter (atomName, o);

                mTimeout.setCallback (boost::bind (&PluginStateWriter::checkTimeout,
                                                 this));
                mTimeout.setTimes (0, 0);
                mTimeout.start ();
            }
        }
        
        virtual ~PluginStateWriter () {};

};

#endif

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