/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * 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://www.hdfgroup.org/licenses. * * If you do not have access to either file, you may request a copy from * * help@hdfgroup.org. * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */ /************************************************************ This example illustrates the concept of the virtual dataset. Excalibur use case with k=2 and m=3. This file is intended for use with HDF5 Library version 1.10 ************************************************************/ /* EIP Add link to the picture */ #include "hdf5.h" #include #include #define FILE "vds-exc.h5" #define DATASET "VDS-Excalibur" #define VDSDIM0 0 #define VDSDIM1 15 #define VDSDIM2 6 #define KDIM0 0 #define KDIM1 2 #define KDIM2 6 #define NDIM0 0 #define NDIM1 3 #define NDIM2 6 #define RANK 3 const char *SRC_FILE[] = {"a.h5", "b.h5", "c.h5", "d.h5", "e.h5", "f.h5"}; const char *SRC_DATASET[] = {"A", "B", "C", "D", "E", "F"}; int main(void) { hid_t file, space, ksrc_space, nsrc_space, vspace, src_space, dset; /* Handles */ hid_t dcpl; herr_t status; hsize_t vdsdims[3] = {VDSDIM0, VDSDIM1, VDSDIM2}, vdsdims_max[3] = {H5S_UNLIMITED, VDSDIM1, VDSDIM2}, kdims[3] = {KDIM0, KDIM1, KDIM2}, kdims_max[3] = {H5S_UNLIMITED, KDIM1, KDIM2}, ndims[3] = {NDIM0, NDIM1, NDIM2}, ndims_max[3] = {H5S_UNLIMITED, NDIM1, NDIM2}, start[3], /* Hyperslab parameters */ count[3], block[3]; hsize_t start_out[3], stride_out[3], count_out[3], block_out[3]; int k = 2; int n = 3; int i; H5D_layout_t layout; /* Storage layout */ size_t num_map; /* Number of mappings */ ssize_t len; /* Length of the string; also a return value */ char *filename; char *dsetname; file = H5Fcreate(FILE, H5F_ACC_TRUNC, H5P_DEFAULT, H5P_DEFAULT); /* Create VDS dataspace. */ space = H5Screate_simple(RANK, vdsdims, vdsdims_max); /* Create dataspaces for A, C, and E datasets. */ ksrc_space = H5Screate_simple(RANK, kdims, kdims_max); /* Create dataspaces for B, D, and F datasets. */ nsrc_space = H5Screate_simple(RANK, ndims, ndims_max); /* Create VDS creation property */ dcpl = H5Pcreate(H5P_DATASET_CREATE); /* Initialize hyperslab values */ start[0] = 0; start[1] = 0; start[2] = 0; count[0] = H5S_UNLIMITED; count[1] = 1; count[2] = 1; block[0] = 1; block[1] = k; block[2] = VDSDIM2; /* * Build the mappings for A, C and E source datasets. * Unlimited hyperslab selection is the same in the source datasets. * Unlimited hyperslab selections in the virtual dataset have different offsets. */ status = H5Sselect_hyperslab(ksrc_space, H5S_SELECT_SET, start, NULL, count, block); for (i = 0; i < 3; i++) { start[1] = (hsize_t)((k + n) * i); status = H5Sselect_hyperslab(space, H5S_SELECT_SET, start, NULL, count, block); status = H5Pset_virtual(dcpl, space, SRC_FILE[2 * i], SRC_DATASET[2 * i], ksrc_space); } /* Reinitialize start[1] and block[1] to build the second set of mappings. */ start[1] = 0; block[1] = n; /* * Build the mappings for B, D and F source datasets. * Unlimited hyperslab selection is the same in the source datasets. * Unlimited hyperslab selections in the virtual dataset have different offsets. */ status = H5Sselect_hyperslab(nsrc_space, H5S_SELECT_SET, start, NULL, count, block); for (i = 0; i < 3; i++) { start[1] = (hsize_t)(k + (k + n) * i); status = H5Sselect_hyperslab(space, H5S_SELECT_SET, start, NULL, count, block); status = H5Pset_virtual(dcpl, space, SRC_FILE[2 * i + 1], SRC_DATASET[2 * i + 1], nsrc_space); } /* Create a virtual dataset */ dset = H5Dcreate2(file, DATASET, H5T_NATIVE_INT, space, H5P_DEFAULT, dcpl, H5P_DEFAULT); status = H5Sclose(space); status = H5Sclose(nsrc_space); status = H5Sclose(ksrc_space); status = H5Dclose(dset); status = H5Fclose(file); /* * Now we begin the read section of this example. */ /* * Open file and dataset using the default properties. */ file = H5Fopen(FILE, H5F_ACC_RDONLY, H5P_DEFAULT); dset = H5Dopen2(file, DATASET, H5P_DEFAULT); /* * Get creation property list and mapping properties. */ dcpl = H5Dget_create_plist(dset); /* * Get storage layout. */ layout = H5Pget_layout(dcpl); if (H5D_VIRTUAL == layout) printf(" Dataset has a virtual layout \n"); else printf("Wrong layout found \n"); /* * Find number of mappings. */ status = H5Pget_virtual_count(dcpl, &num_map); printf(" Number of mappings is %lu\n", (unsigned long)num_map); /* * Get mapping parameters for each mapping. */ for (i = 0; i < (int)num_map; i++) { printf(" Mapping %d \n", i); printf(" Selection in the virtual dataset \n"); /* Get selection in the virtual dataset */ vspace = H5Pget_virtual_vspace(dcpl, (size_t)i); if (H5Sget_select_type(vspace) == H5S_SEL_HYPERSLABS) { if (H5Sis_regular_hyperslab(vspace)) { status = H5Sget_regular_hyperslab(vspace, start_out, stride_out, count_out, block_out); printf(" start = [%llu, %llu, %llu] \n", (unsigned long long)start_out[0], (unsigned long long)start_out[1], (unsigned long long)start_out[2]); printf(" stride = [%llu, %llu, %llu] \n", (unsigned long long)stride_out[0], (unsigned long long)stride_out[1], (unsigned long long)stride_out[2]); printf(" count = [%llu, %llu, %llu] \n", (unsigned long long)count_out[0], (unsigned long long)count_out[1], (unsigned long long)count_out[2]); printf(" block = [%llu, %llu, %llu] \n", (unsigned long long)block_out[0], (unsigned long long)block_out[1], (unsigned long long)block_out[2]); } } /* Get source file name */ len = H5Pget_virtual_filename(dcpl, (size_t)i, NULL, 0); filename = (char *)malloc((size_t)len * sizeof(char) + 1); H5Pget_virtual_filename(dcpl, (size_t)i, filename, len + 1); printf(" Source filename %s\n", filename); /* Get source dataset name */ len = H5Pget_virtual_dsetname(dcpl, (size_t)i, NULL, 0); dsetname = (char *)malloc((size_t)len * sizeof(char) + 1); H5Pget_virtual_dsetname(dcpl, (size_t)i, dsetname, len + 1); printf(" Source dataset name %s\n", dsetname); /* Get selection in the source dataset */ printf(" Selection in the source dataset \n"); src_space = H5Pget_virtual_srcspace(dcpl, (size_t)i); if (H5Sget_select_type(src_space) == H5S_SEL_HYPERSLABS) { if (H5Sis_regular_hyperslab(vspace)) { status = H5Sget_regular_hyperslab(src_space, start_out, stride_out, count_out, block_out); printf(" start = [%llu, %llu, %llu] \n", (unsigned long long)start_out[0], (unsigned long long)start_out[1], (unsigned long long)start_out[2]); printf(" stride = [%llu, %llu, %llu] \n", (unsigned long long)stride_out[0], (unsigned long long)stride_out[1], (unsigned long long)stride_out[2]); printf(" count = [%llu, %llu, %llu] \n", (unsigned long long)count_out[0], (unsigned long long)count_out[1], (unsigned long long)count_out[2]); printf(" block = [%llu, %llu, %llu] \n", (unsigned long long)block_out[0], (unsigned long long)block_out[1], (unsigned long long)block_out[2]); } } H5Sclose(vspace); H5Sclose(src_space); free(filename); free(dsetname); } /* EIP read data back */ /* * Close and release resources. */ status = H5Pclose(dcpl); status = H5Dclose(dset); status = H5Fclose(file); return 0; }