[svn-r12898] Description:

	Added new example for datasets regions; it uses two new functions
	H5Iget_name and H5Rget_name to get name of the dataset the region refernce points to.

Platforms tested:
	heping

1 files changed, 198 insertions, 0 deletions

diff --git a/examples/h5_ref2reg.c b/examples/h5_ref2reg.c
new file mode 100644
index 0000000..e24dcde
--- /dev/null
+++ b/examples/h5_ref2reg.c
@@ -0,0 +1,198 @@
+/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *                                                                               * Copyright by  The HDF Group (THG) and                                     *                                                                               *               The Board of Trustees of the University of Illinois.        *                                                                               * All rights reserved.                                                      *                                                                               *                                                                           *                                                                               * This file is part of HDF5.  The full HDF5 copyright notice, including     *                                                                               * terms governing use, modification, and redistribution, is contained in    *                                                                               * the files COPYING and Copyright.html.  COPYING can be found at the root   *                                                                               * of the source code distribution tree; Copyright.html can be found at the  *                                                                               * root level of an installed copy of the electronic HDF5 document set and   *                                                                               * is linked from the top-level documents page.  It can also be found at     *                                                                               * http://www.hdfgroup.org/HDF5/doc/Copyright.html.  If you do not have      *                                                                               * access to either file, you may request a copy from help@hdfgroup.org.     *                                                                               * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */          
+/*
+    This program shows how to create, store and dereference references 
+    to the dataset regions.
+
+    It creates a file and writes a two dimensional integer dataset
+    to it. Then it creates a dataset to store region references in. It 
+    stores references to a hyperslab and 3 points selected (for the
+    integer dataset previously created). 
+
+    It then reopens the references dataset, reads and dereferences the 
+    region references, and then reads and displays the selected hyperslab 
+    and selected elements data from the integer dataset.
+*/
+
+#include "hdf5.h"
+
+#define filename "REF_REG.h5"
+#define dsetnamev "MATRIX"
+#define dsetnamer "REGION_REFERENCES"
+
+int main(void)
+{
+    hid_t file_id;        /* file identifier */
+    hid_t space_id;       /* dataspace identifiers */
+    hid_t spacer_id;      
+    hid_t dsetv_id;       /*dataset identifiers*/
+    hid_t dsetr_id;      
+    hsize_t dims[2] =  {2,9};
+    hsize_t dimsr[1] =  {2};
+    int rank = 2;
+    int rankr =1;
+    herr_t status;
+    hdset_reg_ref_t ref[2];
+    hdset_reg_ref_t ref_out[2];
+    int data[2][9] = {{1,1,2,3,3,4,5,5,6},{1,2,2,3,4,4,5,6,6}};
+    int data_out[2][9] = {{0,0,0,0,0,0,0,0,0},{0,0,0,0,0,0,0,0,0}};
+    hsize_t start[2];
+    hsize_t count[2];
+    hsize_t coord[2][3] = {{0, 0, 1}, {6, 0, 8}};
+    unsigned num_points = 3;
+    int i, j;
+    size_t name_size1, name_size2;
+    char buf1[10], buf2[10];
+
+    /* 
+     * Create file with default file access and file creation properties.
+     */
+    file_id = H5Fcreate(filename, H5F_ACC_TRUNC, H5P_DEFAULT, H5P_DEFAULT);
+
+    /* 
+     * Create dataspace for datasets.
+     */
+    space_id = H5Screate_simple(rank, dims, NULL);
+    spacer_id = H5Screate_simple(rankr, dimsr, NULL);
+
+    /* 
+     * Create integer dataset. 
+     */
+    dsetv_id = H5Dcreate(file_id, dsetnamev, H5T_NATIVE_INT, space_id, H5P_DEFAULT);
+
+    /* 
+     * Write data to the dataset.
+     */
+    status = H5Dwrite(dsetv_id, H5T_NATIVE_INT, H5S_ALL , H5S_ALL, H5P_DEFAULT,data);
+    status = H5Dclose(dsetv_id);
+
+    /* 
+     * Dataset with references.
+     */
+    dsetr_id = H5Dcreate(file_id, dsetnamer, H5T_STD_REF_DSETREG, spacer_id, H5P_DEFAULT);
+
+    /*
+     * Create a reference to the hyperslab.
+     */
+    start[0] = 0; 
+    start[1] = 3; 
+    count[0] = 2;
+    count[1] = 3;
+    status = H5Sselect_hyperslab(space_id,H5S_SELECT_SET,start,NULL,count,NULL);
+    status = H5Rcreate(&ref[0], file_id, dsetnamev, H5R_DATASET_REGION, space_id);
+
+    /*
+     * Create a reference to elements selection.
+     */
+    status = H5Sselect_none(space_id);
+    status = H5Sselect_elements(space_id, H5S_SELECT_SET, num_points,
+                                (const hsize_t **)coord);
+    status = H5Rcreate(&ref[1], file_id, dsetnamev, H5R_DATASET_REGION, space_id);
+
+    /*
+     * Write dataset with the references.
+     */
+    status = H5Dwrite(dsetr_id, H5T_STD_REF_DSETREG, H5S_ALL, H5S_ALL, H5P_DEFAULT,ref);
+
+    /*
+     * Close all objects.
+     */
+    status = H5Sclose(space_id);
+    status = H5Sclose(spacer_id);
+    status = H5Dclose(dsetr_id);
+    status = H5Fclose(file_id);
+
+    /*
+     * Reopen the file to read selections back.
+     */
+    file_id = H5Fopen(filename, H5F_ACC_RDWR,  H5P_DEFAULT);
+
+    /*
+     * Reopen the dataset with object references and read references 
+     * to the buffer.
+     */
+    dsetr_id = H5Dopen (file_id, dsetnamer);
+
+    status = H5Dread(dsetr_id, H5T_STD_REF_DSETREG, H5S_ALL, H5S_ALL, 
+                   H5P_DEFAULT, ref_out);
+
+    /* 
+     * Dereference the first reference.
+     */
+    dsetv_id = H5Rdereference(dsetr_id, H5R_DATASET_REGION, &ref_out[0]);
+    /*
+     * Get name of the dataset the first region reference points to
+     * using H5Rget_name 
+     */
+    name_size1 = H5Rget_name(dsetr_id, H5R_DATASET_REGION, &ref_out[0], (char*)buf1, 10);      
+    printf (" Dataset's name (returned by H5Rget_name) the reference points to is %s, name length is %d\n", buf1, (int)name_size1); 
+    /*
+     * Get name of the dataset the first region reference points to
+     * using H5Iget_name 
+     */
+    name_size2 = H5Iget_name(dsetv_id, (char*)buf2, 10); 
+    printf (" Dataset's name (returned by H5Iget_name) the reference points to is %s, name length is %d\n", buf2, (int)name_size2); 
+
+    space_id = H5Rget_region(dsetr_id, H5R_DATASET_REGION,&ref_out[0]);
+
+    /* 
+     * Read and display hyperslab selection from the dataset.
+     */
+
+    status = H5Dread(dsetv_id, H5T_NATIVE_INT, H5S_ALL, space_id, 
+                   H5P_DEFAULT, data_out);
+    printf("Selected hyperslab: ");
+    for (i = 0; i <= 1; i++)
+    {   
+        printf("\n");
+        for (j = 0; j <= 8; j++)
+            printf("%d ", data_out[i][j]);
+    }
+    printf("\n");
+
+    /*
+     * Close dataspace and the dataset.
+     */
+    status = H5Sclose(space_id);
+    status = H5Dclose(dsetv_id);
+
+    /*
+     * Initialize data_out array again to get point selection.
+     */
+    for (i = 0; i <= 1; i++)
+        for (j = 0; j <= 8; j++)
+            data_out[i][j] = 0;
+
+    /*
+     * Dereference the second reference.
+     */
+    dsetv_id = H5Rdereference(dsetr_id, H5R_DATASET_REGION, &ref_out[1]);
+    space_id = H5Rget_region(dsetv_id, H5R_DATASET_REGION,&ref_out[1]);
+
+    /*
+     * Read selected data from the dataset.
+     */
+
+    status = H5Dread(dsetv_id, H5T_NATIVE_INT, H5S_ALL, space_id, 
+                   H5P_DEFAULT, data_out);
+    printf("Selected points: ");
+    for (i = 0; i <= 1; i++)
+    {   
+        printf("\n");
+        for (j = 0; j <= 8; j++)
+            printf("%d ", data_out[i][j]);
+    }
+    printf("\n");
+
+    /*
+     * Close dataspace and the dataset.
+     */
+    status = H5Sclose(space_id);
+    status = H5Dclose(dsetv_id);
+    status = H5Dclose(dsetr_id);
+    status = H5Fclose(file_id);
+
+    return 0;
+}
+    
+
+