HDFArray.cc

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// This file is part of the hdf4 data handler for the OPeNDAP data server.

// Copyright (c) 2005 OPeNDAP, Inc.
// Author: James Gallagher <jgallagher@opendap.org>
//
// This 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 software 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 software; 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.

// Copyright 1996, by the California Institute of Technology.
// ALL RIGHTS RESERVED. United States Government Sponsorship
// acknowledged. Any commercial use must be negotiated with the
// Office of Technology Transfer at the California Institute of
// Technology. This software may be subject to U.S. export control
// laws and regulations. By accepting this software, the user
// agrees to comply with all applicable U.S. export laws and
// regulations. User has the responsibility to obtain export
// licenses, or other export authority as may be required before
// exporting such information to foreign countries or providing
// access to foreign persons.

// Author: Todd Karakashian, NASA/Jet Propulsion Laboratory
//         Todd.K.Karakashian@jpl.nasa.gov
//

#include "config_hdf.h"
//#define DODS_DEBUG 1

#include <vector>

// Include this on linux to suppres an annoying warning about multiple
// definitions of MIN and MAX.
#ifdef HAVE_SYS_PARAM_H
#include <sys/param.h>
#endif
#include <mfhdf.h>

#include <hdfclass.h>
#include <hcstream.h>

#include <escaping.h>
#include <Error.h>
#include <debug.h>
#include <BESDebug.h>

#include "HDFArray.h"
#include "dhdferr.h"

HDFArray::HDFArray(const string &n, const string &d, BaseType * v) :
        Array(n, d, v) {
}

HDFArray::~HDFArray() {
}

BaseType *HDFArray::ptr_duplicate() {
        return new HDFArray(*this);
}
void LoadArrayFromSDS(HDFArray * ar, const hdf_sds & sds);
void LoadArrayFromGR(HDFArray * ar, const hdf_gri & gr);

// Read in an Array from either an SDS or a GR in an HDF file.
bool HDFArray::read() {
        int err = 0;
        int status = read_tagref(-1, -1, err);

        if (err)
                throw Error(unknown_error, "Could not read from dataset.");

        return status;
}

// todo: refactor: get rid of the err value-result parameter; throw from
// within this method.
bool HDFArray::read_tagref(int32 tag, int32 ref, int &err) {
        if (read_p())
                return true;

        // get the HDF dataset name, SDS name
        string hdf_file = dataset();
        string hdf_name = this->name();

        // get slab constraint
        vector<int> start, edge, stride;
        bool isslab = GetSlabConstraint(start, edge, stride);

        bool foundsds = false;
        hdf_sds sds;
        if (tag == -1 || tag == DFTAG_NDG) {
                if (SDSExists(hdf_file.c_str(), hdf_name.c_str())) {
                        hdfistream_sds sdsin(hdf_file.c_str());
                        if (ref != -1) {
                                BESDEBUG("h4", "sds seek with ref = " << ref << endl);
                                sdsin.seek_ref(ref);
                        } else {
                                BESDEBUG("h4", "sds seek with name = '" << hdf_name << "'" << endl);
                                sdsin.seek(hdf_name.c_str());
                        }
                        if (isslab)
                                sdsin.setslab(start, edge, stride, false);
                        sdsin >> sds;
                        sdsin.close();
                        foundsds = true;
                }
        }

        bool foundgr = false;
        hdf_gri gr;
        if (!foundsds && (tag == -1 || tag == DFTAG_VG)) {
                if (GRExists(hdf_file.c_str(), hdf_name.c_str())) {
                        hdfistream_gri grin(hdf_file.c_str());
                        if (ref != -1)
                                grin.seek_ref(ref);
                        else
                                grin.seek(hdf_name.c_str());
                        if (isslab)
                                grin.setslab(start, edge, stride, false);
                        grin >> gr;
                        grin.close();
                        foundgr = true;
                }
        }

        // Todo: refactor: move this stuff up into the above if stmts.
        if (foundsds)
                LoadArrayFromSDS(this, sds);
        else if (foundgr)
                LoadArrayFromGR(this, gr);

        if (foundgr || foundsds) {
                set_read_p(true); // Moved here; see bug 136
                err = 0; // no error
                return true;
        } else {
                err = 1;
                return false;
        }
}

// Read the slab constraint parameters; the arrays start_array, edge_array,
// stride_array.  Returns true if there is a slab constraint, false otherwise.
bool HDFArray::GetSlabConstraint(vector<int>&start_array,
                vector<int>&edge_array, vector<int>&stride_array) {
        int start = 0, stop = 0, stride = 0;
        int edge = 0;

        start_array = vector<int> (0);
        edge_array = vector<int> (0);
        stride_array = vector<int> (0);

        for (Array::Dim_iter p = dim_begin(); p != dim_end(); ++p) {
                start = dimension_start(p, true);
                stride = dimension_stride(p, true);
                stop = dimension_stop(p, true);
                if (start == 0 && stop == 0 && stride == 0)
                        return false; // no slab constraint
                if (start > stop)
                        THROW(dhdferr_arrcons);
                edge = (int) ((stop - start) / stride) + 1;
                if (start + edge > dimension_size(p))
                        THROW(dhdferr_arrcons);

                start_array.push_back(start);
                edge_array.push_back(edge);
                stride_array.push_back(stride);
        }
        return true;
}

void HDFArray::transfer_attributes(AttrTable *at) {
        BESDEBUG("h4","Transferring attributes for " << name() << endl);

        BaseType::transfer_attributes(at);

        BESDEBUG("h4","...Now looking for the " << name() << " _dim_n containers." << endl);

        // Here we should look for the *_dim_n where '*' is name() and n is 0, 1, ...
        string dim_name_base = name() + "_dim_";

        AttrTable::Attr_iter a_p = at->attr_begin();
        while (a_p != at->attr_end()) {
                string::size_type i = at->get_name(a_p).find(dim_name_base);
                // Found a matching container?
                // To avoid matching both Month_dim_0 and  DayOfMonth_dim_0, et c.,
                // check that i == 0 and not just i != string::npos. jhrg 8/17/11
                if (i == 0 && at->get_attr_type(a_p) == Attr_container) {
                        AttrTable *dim = at->get_attr_table(a_p);
                        try {
                                BESDEBUG("h4","Found a dimension container for " << name() << endl);
                                transfer_dimension_attribute(dim);
                        }
                        catch (Error &e) {
                                BESDEBUG("h4","Caught an error transferring dimension attribute " << dim->get_name() << " for variable " << name() << endl);
                                throw e;
                        }
                }

                a_p++;
        }
}

void HDFArray::transfer_dimension_attribute(AttrTable *dim) {
        // Mark the table as not global
        dim->set_is_global_attribute(false);
        // copy the table
        AttrTable *at = new AttrTable(*dim);
        // add it to this variable using just the 'dim_<digit>' part of the name
        string name = at->get_name().substr(at->get_name().find("dim"));
        get_attr_table().append_container(at, name);
}