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authorJerome Soumagne <jsoumagne@hdfgroup.org>2019-07-16 16:15:43 (GMT)
committerJerome Soumagne <jsoumagne@hdfgroup.org>2019-10-08 19:30:24 (GMT)
commitae490016b9659d4e31e0e242d0653daf02b7c83c (patch)
treee057dde8bb12749d9ae3ed8e4b7ddc3b63fd0ff2 /examples/h5_ref_extern.c
parent0f4e080309d09a5f0d6911efce064ee487a759be (diff)
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Add new H5R API that abstracts object, region and attribute reference types
Also support references to external files Add new H5T_REF type and type conversion routines Support conversion from H5T_REF_OBJ/DSET_REG to H5T_REF Add H5Treclaim() API to reclaim memory of vlen/reference types Deprecate H5Dvlen_reclaim() Fix H5T_vlen_reclaim() and H5T_reclaim() to use private callback Add H5T_ref_reclaim() Move previous H5R APIs to H5Rdeprec.c Clean up H5Ocopy Separate H5O_copy_expand_ref() to H5Ocopy_ref() Add support for copying new reference types Clean up deprecated routines to go through VOL and same code path Fix return codes in existing trefer.c test Rename trefer.c to trefer_deprec.c trefer.c is for new references Add performance test for trefer Add additional obj_copy_ref test Make use of tokens and blobs to store references Skip blob encoding for object references Start adding new reference examples
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+/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
+ * Copyright by The HDF Group. *
+ * 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 COPYING file, which can be found at the root of the source code *
+ * distribution tree, or in https://support.hdfgroup.org/ftp/HDF5/releases. *
+ * If you do not have access to either file, you may request a copy from *
+ * help@hdfgroup.org. *
+ * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
+
+ /*
+ * The example below illustrates the use of the new API with files that are
+ * opened read-only. Created references to the objects in that file are
+ * stored into a separate file, and accessed from that file, without the user
+ * explicitly opening the original file that was referenced.
+ */
+
+#include <stdlib.h>
+
+#include "hdf5.h"
+#include <assert.h>
+
+#define H5FILE_NAME1 "refer_extern1.h5"
+#define H5FILE_NAME2 "refer_extern2.h5"
+
+#define NDIMS 1 /* Number of dimensions */
+#define BUF_SIZE 4 /* Size of example buffer */
+#define NREFS 1 /* Number of references */
+
+int
+main(void) {
+ hid_t file1, dset1, space1;
+ hsize_t dset1_dims[NDIMS] = { BUF_SIZE };
+ int dset_buf[BUF_SIZE];
+
+ hid_t file2, dset2, space2;
+ hsize_t dset2_dims[NDIMS] = { NREFS };
+ H5R_ref_t ref_buf[NREFS] = { 0 };
+ H5O_type_t obj_type;
+ int i;
+
+ for (i = 0; i < BUF_SIZE; i++)
+ dset_buf[i] = i;
+
+ /* Create file with one dataset and close it */
+ file1 = H5Fcreate(H5FILE_NAME1, H5F_ACC_TRUNC, H5P_DEFAULT, H5P_DEFAULT);
+ space1 = H5Screate_simple(NDIMS, dset1_dims, NULL);
+ dset1 = H5Dcreate2(file1, "dataset1", H5T_NATIVE_INT, space1, H5P_DEFAULT,
+ H5P_DEFAULT, H5P_DEFAULT);
+ H5Dwrite(dset1, H5T_NATIVE_INT, H5S_ALL, H5S_ALL, H5P_DEFAULT, dset_buf);
+ H5Dclose(dset1);
+ H5Sclose(space1);
+ H5Fclose(file1);
+
+ /* Create reference to dataset1 in "refer_extern1.h5" */
+ file1 = H5Fopen(H5FILE_NAME1, H5F_ACC_RDONLY, H5P_DEFAULT);
+ H5Rcreate_object(file1, "dataset1", &ref_buf[0]);
+ H5Fclose(file1);
+
+ /* Store reference in dataset in separate file "refer_extern2.h5" */
+ file2 = H5Fcreate(H5FILE_NAME2, H5F_ACC_TRUNC, H5P_DEFAULT, H5P_DEFAULT);
+ space2 = H5Screate_simple(NDIMS, dset2_dims, NULL);
+ dset2 = H5Dcreate2(file2, "references", H5T_STD_REF, space2, H5P_DEFAULT,
+ H5P_DEFAULT, H5P_DEFAULT);
+ H5Dwrite(dset2, H5T_STD_REF, H5S_ALL, H5S_ALL, H5P_DEFAULT, ref_buf);
+ H5Dclose(dset2);
+ H5Sclose(space2);
+ H5Fclose(file2);
+ H5Rdestroy(&ref_buf[0]);
+
+ /* Read reference back from "refer_extern2.h5" */
+ file2 = H5Fopen(H5FILE_NAME2, H5F_ACC_RDONLY, H5P_DEFAULT);
+ dset2 = H5Dopen2(file2, "references", H5P_DEFAULT);
+ H5Dread(dset2, H5T_STD_REF, H5S_ALL, H5S_ALL, H5P_DEFAULT, ref_buf);
+ H5Dclose(dset2);
+ H5Fclose(file2);
+
+ /* Access reference and read dataset data without opening original file */
+ assert(H5Rget_type((const H5R_ref_t *)&ref_buf[0]) == H5R_OBJECT2);
+ H5Rget_obj_type3((const H5R_ref_t *)&ref_buf[0], H5P_DEFAULT, &obj_type);
+ assert(obj_type == H5O_TYPE_DATASET);
+ dset1 = H5Ropen_object((const H5R_ref_t *)&ref_buf[0], H5P_DEFAULT, H5P_DEFAULT);
+ H5Dread(dset1, H5T_NATIVE_INT, H5S_ALL, H5S_ALL, H5P_DEFAULT, dset_buf);
+ H5Dclose(dset1);
+ H5Rdestroy(&ref_buf[0]);
+
+ for (i = 0; i < BUF_SIZE; i++)
+ assert(dset_buf[i] == i);
+
+ return 0;
+}
+