HDF5Url.cc

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// This file is part of hdf5_handler a HDF5 file handler for the OPeNDAP
// data server.
 
// Author: Hyo-Kyung Lee <hyoklee@hdfgroup.org> and Kent Yang
// <myang6@hdfgroup.org> 
 
// Copyright (c) 2009-2023 The HDF Group, Inc. and OPeNDAP, Inc.
//
// 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 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.
// You can contact The HDF Group, Inc. at 410 E University Ave,
// Suite 200, Champaign, IL 61820  

 
 
 
#include <string>
#include <memory>
#include "HDF5Url.h"
#include <libdap/InternalErr.h>
 
using namespace std;
using namespace libdap;
 
HDF5Url::HDF5Url(const string &n, const string &vpath,const string &d) : Url(n, d),var_path(vpath)
{
}
 
BaseType *HDF5Url::ptr_duplicate()
{
    auto HDF5Url_unique = make_unique<HDF5Url>(*this);
    return HDF5Url_unique.release();
}
 
bool HDF5Url::read()
{
 
   hid_t file_id = H5Fopen(dataset().c_str(),H5F_ACC_RDONLY,H5P_DEFAULT);
    if(file_id < 0) {
        throw InternalErr(__FILE__,__LINE__, "Fail to obtain the HDF5 file ID .");
    }
 
    hid_t dset_id = -1;
    if(true == is_dap4())
        dset_id = H5Dopen2(file_id,var_path.c_str(),H5P_DEFAULT);
    else
        dset_id = H5Dopen2(file_id,name().c_str(),H5P_DEFAULT);
 
    if(dset_id < 0) {
        H5Fclose(file_id);
        throw InternalErr(__FILE__,__LINE__, "Fail to obtain the datatype .");
    }
 
    hobj_ref_t rbuf;
 
    if (H5Dread(dset_id, H5T_STD_REF_OBJ, H5S_ALL, H5S_ALL, H5P_DEFAULT, 
        &rbuf) < 0) {
        H5Dclose(dset_id);
        H5Fclose(file_id);
    throw InternalErr(__FILE__, __LINE__, "H5Dread() failed.");
    }
 
    hid_t did_r = H5RDEREFERENCE(dset_id, H5R_OBJECT, &rbuf);
    char r_name[DODS_NAMELEN];
    if (did_r < 0){
    H5Dclose(dset_id);
        H5Fclose(file_id);
    throw InternalErr(__FILE__, __LINE__, "H5RDEREFERENCE() failed.");
    }
    if (H5Iget_name(did_r, r_name, DODS_NAMELEN) < 0){
    H5Dclose(dset_id);
        H5Fclose(file_id);
        throw InternalErr(__FILE__, __LINE__, "Unable to retrieve the name of the object.");
    }
    string reference = r_name;
    set_value(reference);
 
     // Release the handles.
    H5Dclose(dset_id); 
    H5Fclose(file_id);
 
 
    return true;
}