DmrppArray.h

// -*- mode: c++; c-basic-offset:4 -*-

// This file is part of the BES

// Copyright (c) 2016 OPeNDAP, Inc.
// Author: James Gallagher <jgallagher@opendap.org>
//
// This library 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 2.1 of the License, or (at your option) any later version.
//
// This library 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 this library; if not, write to the Free Software
// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
//
// You can contact OPeNDAP, Inc. at PO Box 112, Saunderstown, RI. 02874-0112.

#ifndef _dmrpp_array_h
#define _dmrpp_array_h 1

#include <string>
#include <vector>

#include <Array.h>

#include "DmrppCommon.h"

// The 'read_serial()' method is more closely related to the original code
// used to read data when the DMR++ handler was initial developed for NASA.
// I modified that code for a while when we built the prototype version of
// the handler, but then morphed that into a version that would support parallel
// access. Defining this symbol will include the old code in the handler,
// although the DmrppArray::read() method will still have to be hacked to
// use it. jhrg 5/10/18
#undef USE_READ_SERIAL

namespace libdap {
class XMLWriter;
}

namespace dmrpp {

/**
 * @brief Extend libdap::Array so that a handler can read data using a DMR++ file.
 *
 * @note A key feature of HDF5 is that is can 'chunk' data, breaking up an
 * array into a number of smaller pieces, each of which can be compressed.
 * This code will read both array data that are chunked (and possibly compressed)
 * as well as code that is not (essentially the entire array is written in a
 * single 'chunk'). Because the two cases are different and susceptible to
 * different kinds of optimizations, we have implemented two different read()
 * methods, one for the 'no chunks' case and one for arrays 'with chunks.'
 */
class DmrppArray: public libdap::Array, public DmrppCommon {

private:
    void _duplicate(const DmrppArray &ts);

    bool is_projected();

    DmrppArray::dimension get_dimension(unsigned int dim_num);

    void insert_constrained_contiguous(Dim_iter p, unsigned long *target_index, std::vector<unsigned int> &subsetAddress,
        const std::vector<unsigned int> &array_shape, char *data);
    virtual void read_contiguous();

#ifdef USE_READ_SERIAL
    virtual void insert_chunk_serial(unsigned int dim, std::vector<unsigned int> *target_element_address,
        std::vector<unsigned int> *chunk_source_address, Chunk *chunk);
    virtual void read_chunks_serial();
#endif

    unsigned long long get_chunk_start(unsigned int dim, const std::vector<unsigned int>& chunk_origin);
    Chunk *find_needed_chunks(unsigned int dim, std::vector<unsigned int> *target_element_address, Chunk *chunk);
    void insert_chunk(unsigned int dim, std::vector<unsigned int> *target_element_address, std::vector<unsigned int> *chunk_element_address,
        Chunk *chunk);
    virtual void read_chunks_parallel();

public:
    DmrppArray(const std::string &n, libdap::BaseType *v);
    DmrppArray(const std::string &n, const std::string &d, libdap::BaseType *v);
    DmrppArray(const DmrppArray &rhs);

    virtual ~DmrppArray()
    {
    }

    DmrppArray &operator=(const DmrppArray &rhs);

    virtual libdap::BaseType *ptr_duplicate();

    virtual bool read();

    virtual unsigned long long get_size(bool constrained = false);
    virtual std::vector<unsigned int> get_shape(bool constrained);

    virtual void print_dap4(libdap::XMLWriter &writer, bool constrained = false);

    virtual void dump(ostream & strm) const;
};

} // namespace dmrpp

#endif // _dmrpp_array_h