sort.h

// -*- mode: c++; tab-width: 4; indent-tabs-mode: t; eval: (progn (c-set-style "stroustrup") (c-set-offset 'innamespace 0)); -*-
// vi:set ts=4 sts=4 sw=4 noet :
// Copyright 2011, 2012, The TPIE development team
// 
// This file is part of TPIE.
// 
// TPIE is free software: you can redistribute it and/or modify it under
// the terms of the GNU Lesser General Public License as published by the
// Free Software Foundation, either version 3 of the License, or (at your
// option) any later version.
// 
// TPIE is distributed in the hope that it will be useful, but WITHOUT ANY
// WARRANTY; without even the implied warranty of MERCHANTABILITY or
// FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public
// License for more details.
// 
// You should have received a copy of the GNU Lesser General Public License
// along with TPIE.  If not, see <http://www.gnu.org/licenses/>

#ifndef __TPIE_PIPELINING_SORT_H__
#define __TPIE_PIPELINING_SORT_H__

#include <tpie/pipelining/node.h>
#include <tpie/pipelining/pipe_base.h>
#include <tpie/pipelining/factory_base.h>
#include <tpie/pipelining/merge_sorter.h>
#include <tpie/parallel_sort.h>
#include <tpie/file_stream.h>
#include <tpie/tempname.h>
#include <tpie/memory.h>
#include <queue>
#include <boost/shared_ptr.hpp>

namespace tpie {

namespace pipelining {

namespace bits {

template <typename T, typename pred_t>
class sort_calc_t;

template <typename T, typename pred_t>
class sort_input_t;

template <typename T, typename pred_t>
class sort_output_base : public node {
    // node has virtual dtor
public:
    typedef T item_type;
    typedef merge_sorter<item_type, true, pred_t> sorter_t;
    typedef typename sorter_t::ptr sorterptr;

    sorterptr get_sorter() const {
        return m_sorter;
    }

    void set_calc_node(node & calc) {
        add_dependency(calc);
    }

protected:
    sort_output_base(pred_t pred)
        : m_sorter(new sorter_t(pred))
    {
    }

    sorterptr m_sorter;
};

template <typename T, typename pred_t>
class sort_pull_output_t : public sort_output_base<T, pred_t> {
public:
    typedef T item_type;
    typedef merge_sorter<item_type, true, pred_t> sorter_t;
    typedef typename sorter_t::ptr sorterptr;

    inline sort_pull_output_t(pred_t pred)
        : sort_output_base<T, pred_t>(pred)
    {
        this->set_minimum_memory(sorter_t::minimum_memory_phase_3());
        this->set_maximum_memory(sorter_t::maximum_memory_phase_3());
        this->set_name("Write sorted output", PRIORITY_INSIGNIFICANT);
        this->set_memory_fraction(1.0);
    }

    virtual void propagate() override {
        this->set_steps(this->m_sorter->item_count());
        this->forward("items", static_cast<stream_size_type>(this->m_sorter->item_count()));
    }

    inline bool can_pull() const {
        return this->m_sorter->can_pull();
    }

    inline item_type pull() {
        this->step();
        return this->m_sorter->pull();
    }

    // Despite this go() implementation, a sort_pull_output_t CANNOT be used as
    // an initiator node. Normally, it is a type error to have a phase without
    // an initiator, but with a passive_sorter you can circumvent this
    // mechanism. Thus we customize the error message printed (but throw the
    // same type of exception.)
    virtual void go() override {
        log_warning() << "Passive sorter used without an initiator in the final merge and output phase.\n"
            << "Define an initiator and pair it up with the pipe from passive_sorter::output()." << std::endl;
        throw not_initiator_node();
    }

protected:
    virtual void set_available_memory(memory_size_type availableMemory) override {
        node::set_available_memory(availableMemory);
        this->m_sorter->set_phase_3_memory(availableMemory);
    }
};

template <typename pred_t, typename dest_t>
class sort_output_t : public sort_output_base<typename dest_t::item_type, pred_t> {
public:
    typedef typename dest_t::item_type item_type;
    typedef sort_output_base<item_type, pred_t> p_t;
    typedef merge_sorter<item_type, true, pred_t> sorter_t;
    typedef typename sorter_t::ptr sorterptr;

    inline sort_output_t(const dest_t & dest, pred_t pred)
        : p_t(pred)
        , dest(dest)
    {
        this->add_push_destination(dest);
        this->set_minimum_memory(sorter_t::minimum_memory_phase_3());
        this->set_maximum_memory(sorter_t::maximum_memory_phase_3());
        this->set_name("Write sorted output", PRIORITY_INSIGNIFICANT);
        this->set_memory_fraction(1.0);
    }

    virtual void propagate() override {
        this->set_steps(this->m_sorter->item_count());
        this->forward("items", static_cast<stream_size_type>(this->m_sorter->item_count()));
    }

    virtual void go() override {
        while (this->m_sorter->can_pull()) {
            dest.push(this->m_sorter->pull());
            this->step();
        }
    }

protected:
    virtual void set_available_memory(memory_size_type availableMemory) override {
        node::set_available_memory(availableMemory);
        this->m_sorter->set_phase_3_memory(availableMemory);
    }

private:
    dest_t dest;
};

template <typename T, typename pred_t>
class sort_calc_t : public node {
public:
    typedef T item_type;
    typedef merge_sorter<item_type, true, pred_t> sorter_t;
    typedef typename sorter_t::ptr sorterptr;

    typedef sort_output_base<T, pred_t> Output;

    inline sort_calc_t(const sort_calc_t & other)
        : node(other)
        , m_sorter(other.m_sorter)
        , dest(other.dest)
    {
    }

    template <typename dest_t>
    inline sort_calc_t(dest_t dest)
        : dest(new dest_t(dest))
    {
        m_sorter = this->dest->get_sorter();
        this->dest->set_calc_node(*this);
        init();
    }

    inline sort_calc_t(sorterptr sorter)
        : m_sorter(sorter)
    {
        init();
    }

    void init() {
        set_minimum_memory(sorter_t::minimum_memory_phase_2());
        set_name("Perform merge heap", PRIORITY_SIGNIFICANT);
        set_memory_fraction(1.0);
    }

    virtual void propagate() override {
        set_steps(1000);
    }

    virtual void go() override {
        progress_indicator_base * pi = proxy_progress_indicator();
        m_sorter->calc(*pi);
    }

    virtual bool can_evacuate() override {
        return true;
    }

    virtual void evacuate() override {
        m_sorter->evacuate_before_reporting();
    }

    sorterptr get_sorter() const {
        return m_sorter;
    }

    void set_input_node(node & input) {
        add_dependency(input);
    }

protected:
    virtual void set_available_memory(memory_size_type availableMemory) override {
        node::set_available_memory(availableMemory);
        m_sorter->set_phase_2_memory(availableMemory);
    }

private:
    sorterptr m_sorter;
    boost::shared_ptr<Output> dest;
};

template <typename T, typename pred_t>
class sort_input_t : public node {
public:
    typedef T item_type;
    typedef merge_sorter<item_type, true, pred_t> sorter_t;
    typedef typename sorter_t::ptr sorterptr;

    inline sort_input_t(sort_calc_t<T, pred_t> dest)
        : m_sorter(dest.get_sorter())
        , dest(dest)
    {
        this->dest.set_input_node(*this);
        set_minimum_memory(sorter_t::minimum_memory_phase_1());
        set_name("Form input runs", PRIORITY_SIGNIFICANT);
        set_memory_fraction(1.0);
    }

    virtual void propagate() override {
        if (this->can_fetch("items"))
            m_sorter->set_items(this->fetch<stream_size_type>("items"));
        m_sorter->begin();
    }

    inline void push(const item_type & item) {
        m_sorter->push(item);
    }

    virtual void end() override {
        node::end();
        m_sorter->end();
    }

    virtual bool can_evacuate() override {
        return true;
    }

    virtual void evacuate() override {
        m_sorter->evacuate_before_merging();
    }

protected:
    virtual void set_available_memory(memory_size_type availableMemory) override {
        node::set_available_memory(availableMemory);
        m_sorter->set_phase_1_memory(availableMemory);
    }

private:
    sorterptr m_sorter;
    sort_calc_t<T, pred_t> dest;
};

template <typename child_t>
class sort_factory_base : public factory_base {
    const child_t & self() const { return *static_cast<const child_t *>(this); }
public:
    template <typename dest_t>
    struct constructed {
    private:
        typedef typename dest_t::item_type item_type;
    public:
        typedef typename child_t::template predicate<item_type>::type pred_type;
        typedef sort_input_t<item_type, pred_type> type;
    };

    template <typename dest_t>
    typename constructed<dest_t>::type construct(const dest_t & dest) const {
        typedef typename dest_t::item_type item_type;
        typedef typename constructed<dest_t>::pred_type pred_type;

        sort_output_t<pred_type, dest_t> output(dest, self().template get_pred<item_type>());
        this->init_sub_node(output);
        sort_calc_t<item_type, pred_type> calc(output);
        this->init_sub_node(calc);
        sort_input_t<item_type, pred_type> input(calc);
        this->init_sub_node(input);

        return input;
    }
};

class default_pred_sort_factory : public sort_factory_base<default_pred_sort_factory> {
public:
    template <typename item_type>
    class predicate {
    public:
        typedef std::less<item_type> type;
    };

    template <typename T>
    std::less<T> get_pred() const {
        return std::less<T>();
    }
};

template <typename pred_t>
class sort_factory : public sort_factory_base<sort_factory<pred_t> > {
public:
    template <typename Dummy>
    class predicate {
    public:
        typedef pred_t type;
    };

    sort_factory(const pred_t & p)
        : pred(p)
    {
    }

    template <typename T>
    pred_t get_pred() const {
        return pred;
    }

private:
    pred_t pred;
};

} // namespace bits

inline pipe_middle<bits::default_pred_sort_factory>
pipesort() {
    typedef bits::default_pred_sort_factory fact;
    return pipe_middle<fact>(fact()).name("Sort");
}

template <typename pred_t>
inline pipe_middle<bits::sort_factory<pred_t> >
pipesort(const pred_t & p) {
    typedef bits::sort_factory<pred_t> fact;
    return pipe_middle<fact>(fact(p)).name("Sort");
}

template <typename T, typename pred_t=std::less<T> >
class passive_sorter;

namespace bits {

template <typename T, typename pred_t>
class passive_sorter_factory : public factory_base {
public:
    typedef sort_pull_output_t<T, pred_t> output_t;
    typedef sort_calc_t<T, pred_t> calc_t;
    typedef sort_input_t<T, pred_t> input_t;
    typedef input_t constructed_type;
    typedef merge_sorter<T, true, pred_t> sorter_t;
    typedef typename sorter_t::ptr sorterptr;

    passive_sorter_factory(output_t & output)
        : output(&output)
    {
    }

    constructed_type construct() const {
        calc_t calc(output->get_sorter());
        output->set_calc_node(calc);
        this->init_node(calc);
        input_t input(calc);
        this->init_node(input);
        return input;
    }

private:
    output_t * output;
};

template <typename T, typename pred_t>
class passive_sorter_factory_2 : public factory_base {
public:
    typedef sort_pull_output_t<T, pred_t> output_t;
    typedef output_t constructed_type;

    passive_sorter_factory_2(const passive_sorter<T, pred_t> & sorter)
        : m_sorter(sorter)
    {
    }

    constructed_type construct() const;

private:
    const passive_sorter<T, pred_t> & m_sorter;
};

} // namespace bits

template <typename T, typename pred_t>
class passive_sorter {
public:
    typedef T item_type;
    typedef merge_sorter<item_type, true, pred_t> sorter_t;
    typedef typename sorter_t::ptr sorterptr;
    typedef bits::sort_pull_output_t<item_type, pred_t> output_t;

    inline passive_sorter(pred_t pred = pred_t())
        : m_sorter(new sorter_t())
        , pred(pred)
        , m_output(pred)
    {
    }

    inline pipe_end<bits::passive_sorter_factory<item_type, pred_t> > input() {
        return bits::passive_sorter_factory<item_type, pred_t>(m_output);
    }

    inline pullpipe_begin<bits::passive_sorter_factory_2<item_type, pred_t> > output() {
        return bits::passive_sorter_factory_2<item_type, pred_t>(*this);
    }

private:
    sorterptr m_sorter;
    pred_t pred;
    output_t m_output;
    passive_sorter(const passive_sorter &);
    passive_sorter & operator=(const passive_sorter &);

    friend class bits::passive_sorter_factory_2<T, pred_t>;
};

namespace bits {

template <typename T, typename pred_t>
typename passive_sorter_factory_2<T, pred_t>::constructed_type
passive_sorter_factory_2<T, pred_t>::construct() const {
    constructed_type res = m_sorter.m_output;
    init_node(res);
    return res;
}

} // namespace bits

} // namespace pipelining

} // namespace tpie

#endif