HDFArray.cc

// 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 suppress 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 <libdap/escaping.h>
#include <libdap/Error.h>
#include <libdap/debug.h>
#include <BESDebug.h>
 
#include "HDFArray.h"
#include "dhdferr.h"
 
using namespace libdap;
using namespace std;
 
HDFArray::HDFArray(const string &n, const string &d, BaseType * v) :
    Array(n, d, v) {
}
 
HDFArray::~HDFArray() = default;
 
 
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;
        vector<int>  edge;
        vector<int>  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;
        int stop = 0;
        int 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 =  ((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
    auto 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);
}