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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.                                                        *
 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */

#include "h5test.h"

/* This test uses many POSIX things that are not available on
 * Windows. We're using a check for fork(2) here as a proxy for
 * all POSIX/Unix/Linux things until this test can be made
 * more platform-independent.
 */
#ifdef H5_HAVE_FORK

#include "use.h"

/* ----------------------------------------------------------------------------
 * Print a common/shared usage message.
 * Receives program name to show default test file name (<program_name>.h5).
 * ----------------------------------------------------------------------------
 */
void
usage(const char *prog)
{
    HDfprintf(stderr, "usage: %s [OPTIONS]\n", prog);
    HDfprintf(stderr, "  OPTIONS\n");
    HDfprintf(stderr, "     -h, --help            Print a usage message and exit\n");
    HDfprintf(stderr, "     -f FN                 Test file name [default: %s.h5]\n", prog);
    HDfprintf(stderr, "     -i N, --iteration=N   Number of iterations to repeat the whole thing. [default: 1]\n");
    HDfprintf(stderr, "     -l w|r                launch writer or reader only. [default: launch both]\n");
    HDfprintf(stderr, "     -n N, --nplanes=N     Number of planes to write/read. [default: 1000]\n");
    HDfprintf(stderr, "     -s N, --swmr=N        Use SWMR mode (0: no, non-0: yes) default is yes\n");
    HDfprintf(stderr, "     -z N, --chunksize=N   Chunk size [default: %d]\n", Chunksize_DFT);
    HDfprintf(stderr, "     -y N, --chunkplanes=N Number of planes per chunk [default: 1]\n");
    HDfprintf(stderr, "\n");
} /* end usage() */

/* ----------------------------------------------------------------------------
 * Setup Use Case parameters by parsing command line options.
 * Includes default values for unspecified options.
 * ----------------------------------------------------------------------------
 */
int
parse_option(int argc, char * const argv[], options_t * opts)
{
    int ret_value=0;
    int c;
    int use_swmr;       /* Need an int to detect errors */

    /* command line options: See function usage for a description */
    const char *nagg_options = "f:hi:l:n:s:y:z:";

    /* suppress getopt from printing error */
    opterr = 0;

    while (1) {
        c = getopt(argc, argv, nagg_options);
        if (-1 == c)
            break;
        switch (c) {
        case 'h':
            usage(opts->progname);
            exit(EXIT_SUCCESS);
            break;
        case 'f':     /* usecase data file name */
            opts->filename = optarg;
            break;
        case 'i':     /* iterations */
            if ((opts->iterations = HDatoi(optarg)) <= 0) {
                HDfprintf(stderr, "bad iterations number %s, must be a positive integer\n", optarg);
                usage(opts->progname);
                Hgoto_error(-1);
            }
            break;
        case 'l':     /* launch reader or writer only */
            switch (*optarg) {
            case 'r': /* reader only */
                opts->launch = UC_READER;
                break;
            case 'w': /* writer only */
                opts->launch = UC_WRITER;
                break;
            default:
                HDfprintf(stderr, "launch value(%c) should be w or r only.\n", *optarg);
                usage(opts->progname);
                Hgoto_error(-1);
                break;
            } /* end switch (reader/writer-only mode toggle) */
            break;
        case 'n':     /* number of planes to write/read */
            if ((opts->nplanes = HDstrtoul(optarg, NULL, 0)) <= 0) {
                HDfprintf(stderr, "bad number of planes %s, must be a positive integer\n", optarg);
                usage(opts->progname);
                Hgoto_error(-1);
            }
            break;
        case 's':     /* use swmr file open mode */
            use_swmr = HDatoi(optarg);
            if (use_swmr != 0 && use_swmr != 1) {
                HDfprintf(stderr, "swmr value should be 0(no) or 1(yes)\n");
                usage(opts->progname);
                Hgoto_error(-1);
            }
            opts->use_swmr = (hbool_t)use_swmr;
            break;
        case 'y':     /* Number of planes per chunk */
            if ((opts->chunkplanes = HDstrtoul(optarg, NULL, 0)) <= 0) {
                HDfprintf(stderr, "bad number of planes per chunk %s, must be a positive integer\n", optarg);
                usage(opts->progname);
                Hgoto_error(-1);
            }
            break;
        case 'z':     /* size of chunk=(z,z) */
            if ((opts->chunksize = HDstrtoull(optarg, NULL, 0)) <= 0) {
                HDfprintf(stderr, "bad chunksize %s, must be a positive integer\n", optarg);
                usage(opts->progname);
                Hgoto_error(-1);
            }
            break;
        case '?':
            HDfprintf(stderr, "getopt returned '%c'.\n", c);
            Hgoto_error(-1);
        default:
            HDfprintf(stderr, "getopt returned unexpected value.\n");
            HDfprintf(stderr, "Unexpected value is %d\n", c);
            Hgoto_error(-1);
        } /* end switch (argument symbol) */
    } /* end while (there are still arguments) */

    /* set test file name if not given */
    if (!opts->filename) {
        /* default data file name is <progname>.h5 */
        if ((opts->filename=(char*)HDmalloc(HDstrlen(opts->progname)+4))==NULL) {
            HDfprintf(stderr, "malloc: failed\n");
            Hgoto_error(-1);
        }
        HDstrcpy(opts->filename, opts->progname);
        HDstrcat(opts->filename, ".h5");
    }

done:
    return(ret_value);
} /* end parse_option() */

/* ----------------------------------------------------------------------------
 * Show parameters used for this use case.
 * ----------------------------------------------------------------------------
 */
void
show_parameters(options_t * opts)
{
    HDprintf("===Parameters used:===\n");
    HDprintf("chunk dims=(%llu, %llu, %llu)\n", (unsigned long long)opts->chunkdims[0],
        (unsigned long long)opts->chunkdims[1], (unsigned long long)opts->chunkdims[2]);
    HDprintf("dataset max dims=(%llu, %llu, %llu)\n", (unsigned long long)opts->max_dims[0],
        (unsigned long long)opts->max_dims[1], (unsigned long long)opts->max_dims[2]);
    HDprintf("number of planes to write=%llu\n", (unsigned long long)opts->nplanes);
    HDprintf("using SWMR mode=%s\n", opts->use_swmr ? "yes(1)" : "no(0)");
    HDprintf("data filename=%s\n", opts->filename);
    HDprintf("launch part=");
        switch (opts->launch) {
        case UC_READWRITE:
            HDprintf("Reader/Writer\n");
            break;
        case UC_WRITER:
            HDprintf("Writer\n");
            break;
        case UC_READER:
            HDprintf("Reader\n");
            break;
        default:
            /* should not happen */
            HDprintf("Illegal part(%d)\n", opts->launch);
        }
    HDprintf("number of iterations=%d (not used yet)\n", opts->iterations);
    HDprintf("===Parameters shown===\n");
} /* end show_parameters() */

/* ----------------------------------------------------------------------------
 * Create the skeleton use case file for testing.
 * It has one 3d dataset using chunked storage.
 * The dataset is (unlimited, chunksize, chunksize).
 * Dataset type is 2 bytes integer.
 * It starts out "empty", i.e., first dimension is 0.
 *
 * Return: 0 succeed; -1 fail.
 * ----------------------------------------------------------------------------
 */
int
create_uc_file(options_t * opts)
{
    hsize_t dims[3];            /* Dataset starting dimensions */
    hid_t fid;                  /* File ID for new HDF5 file */
    hid_t dcpl;                 /* Dataset creation property list */
    hid_t sid;                  /* Dataspace ID */
    hid_t dsid;                 /* Dataset ID */
    H5D_chunk_index_t idx_type; /* Chunk index type */

    if ((fid = H5Fcreate(opts->filename, H5F_ACC_TRUNC, H5P_DEFAULT, opts->fapl_id)) < 0)
        return -1;

    /* Set up dimension sizes */
    dims[0] = 0;
    dims[1] = dims[2] = opts->max_dims[1];

    /* Create dataspace for creating datasets */
    if ((sid = H5Screate_simple(3, dims, opts->max_dims)) < 0)
        return -1;

    /* Create dataset creation property list */
    if ((dcpl = H5Pcreate(H5P_DATASET_CREATE)) < 0)
        return -1;
    if (H5Pset_chunk(dcpl, 3, opts->chunkdims) < 0)
        return -1;

    /* create dataset of progname */
    if ((dsid = H5Dcreate2(fid, opts->progname, UC_DATATYPE, sid, H5P_DEFAULT, dcpl, H5P_DEFAULT)) < 0)
        return -1;

    /* Check that the chunk index type is not version 1 B-tree.
     * Version 1 B-trees are not supported under SWMR.
     */
    if (H5Dget_chunk_index_type(dsid, &idx_type) < 0)
        return -1;
    if (idx_type == H5D_CHUNK_IDX_BTREE) {
        HDfprintf(stderr, "ERROR: Chunk index is version 1 B-tree: aborting.\n");
        return -1;
    }

    /* Close everything */
    if (H5Dclose(dsid) < 0)
        return -1;
    if (H5Pclose(dcpl) < 0)
        return -1;
    if (H5Sclose(sid) < 0)
        return -1;
    if (H5Fclose(fid) < 0)
        return -1;

    return 0;
} /* end create_uc_file() */

/* ----------------------------------------------------------------------------
 * Append planes, each of (1,2*chunksize,2*chunksize) to the dataset.
 * In other words, 4 chunks are appended to the dataset at a time.
 * Fill each plan with the plane number and then write it at the nth plane.
 * Increase the plane number and repeat till the end of dataset, when it
 * reaches chunksize long. End product is a (2*chunksize)^3 cube.
 *
 * Return: 0 succeed; -1 fail.
 * ----------------------------------------------------------------------------
 */
int
write_uc_file(hbool_t tosend, hid_t file_id, options_t * opts)
{
    hid_t     dsid;                         /* dataset ID */
    hid_t     dcpl;                         /* Dataset creation property list */
    UC_CTYPE *buffer, *bufptr;              /* data buffer */
    hsize_t   cz=opts->chunksize;           /* Chunk size */
    hid_t     f_sid;                        /* dataset file space id */
    hid_t     m_sid;                        /* memory space id */
    int       rank;                         /* rank */
    hsize_t   chunk_dims[3];                /* Chunk dimensions */
    hsize_t   dims[3];                      /* Dataspace dimensions */
    hsize_t   memdims[3];                   /* Memory space dimensions */
    hsize_t   start[3] = {0,0,0}, count[3]; /* Hyperslab selection values */
    hsize_t   i, j, k;

    if (TRUE == tosend) {
        /* Send a message that H5Fopen is complete--releasing the file lock */
        h5_send_message(WRITER_MESSAGE, NULL, NULL);
    }

    /* Open the dataset of the program name */
    if ((dsid = H5Dopen2(file_id, opts->progname, H5P_DEFAULT)) < 0) {
        HDfprintf(stderr, "H5Dopen2 failed\n");
        return -1;
    }

    /* Find chunksize used */
    if ((dcpl = H5Dget_create_plist(dsid)) < 0) {
        HDfprintf(stderr, "H5Dget_create_plist failed\n");
        return -1;
    }
    if (H5D_CHUNKED != H5Pget_layout(dcpl)) {
        HDfprintf(stderr, "storage layout is not chunked\n");
        return -1;
    }
    if ((rank = H5Pget_chunk(dcpl, 3, chunk_dims)) != 3) {
        HDfprintf(stderr, "storage rank is not 3\n");
        return -1;
    }

    /* verify chunk_dims against set paramenters */
    if (chunk_dims[0]!=opts->chunkdims[0] || chunk_dims[1] != cz || chunk_dims[2] != cz) {
        HDfprintf(stderr, "chunk size is not as expected. Got dims=(%llu,%llu,%llu)\n",
            (unsigned long long)chunk_dims[0], (unsigned long long)chunk_dims[1],
            (unsigned long long)chunk_dims[2]);
        return -1;
    }

    /* allocate space for data buffer 1 X dims[1] X dims[2] of UC_CTYPE */
    memdims[0]=1;
    memdims[1] = opts->dims[1];
    memdims[2] = opts->dims[2];
    if ((buffer=(UC_CTYPE*)HDmalloc((size_t)memdims[1]*(size_t)memdims[2]*sizeof(UC_CTYPE)))==NULL) {
        HDfprintf(stderr, "malloc: failed\n");
        return -1;
    }

    /*
     * Get dataset rank and dimension.
     */
    f_sid = H5Dget_space(dsid);    /* Get filespace handle first. */
    rank  = H5Sget_simple_extent_ndims(f_sid);
    if (rank != UC_RANK) {
        HDfprintf(stderr, "rank(%d) of dataset does not match\n", rank);
        return -1;
    }
    if (H5Sget_simple_extent_dims(f_sid, dims, NULL) < 0) {
        HDfprintf(stderr, "H5Sget_simple_extent_dims got error\n");
        return -1;
    }
    HDprintf("dataset rank %d, dimensions %llu x %llu x %llu\n",
           rank, (unsigned long long)(dims[0]), (unsigned long long)(dims[1]),
           (unsigned long long)(dims[2]));
    /* verify that file space dims are as expected and are consistent with memory space dims */
    if (dims[0] != 0 || dims[1] != memdims[1] || dims[2] != memdims[2]) {
        HDfprintf(stderr, "dataset is not empty. Got dims=(%llu,%llu,%llu)\n",
            (unsigned long long)dims[0], (unsigned long long)dims[1],
            (unsigned long long)dims[2]);
        return -1;
    }

    /* setup mem-space for buffer */
    if ((m_sid=H5Screate_simple(rank, memdims, NULL))<0) {
        HDfprintf(stderr, "H5Screate_simple for memory failed\n");
        return -1;
    }

    /* write planes */
    count[0]=1;
    count[1]=dims[1];
    count[2]=dims[2];
    for (i=0; i < opts->nplanes; i++) {
        /* fill buffer with value i+1 */
        bufptr = buffer;
        for (j=0; j < dims[1]; j++) {
            for (k=0; k < dims[2]; k++) {
                *bufptr++ = (UC_CTYPE)i;
            }
        }

        /* Cork the dataset's metadata in the cache, if SWMR is enabled */
        if (opts->use_swmr) {
            if (H5Odisable_mdc_flushes(dsid) < 0) {
                HDfprintf(stderr, "H5Odisable_mdc_flushes failed\n");
                return -1;
            }
        }

        /* extend the dataset by one for new plane */
        dims[0]=i+1;
        if (H5Dset_extent(dsid, dims) < 0) {
            HDfprintf(stderr, "H5Dset_extent failed\n");
            return -1;
        }

        /* Get the dataset's dataspace */
        if ((f_sid = H5Dget_space(dsid)) < 0) {
            HDfprintf(stderr, "H5Dset_extent failed\n");
            return -1;
        }

        start[0]=i;
        /* Choose the next plane to write */
        if (H5Sselect_hyperslab(f_sid, H5S_SELECT_SET, start, NULL, count, NULL) < 0) {
            HDfprintf(stderr, "Failed H5Sselect_hyperslab\n");
            return -1;
        }

        /* Write plane to the dataset */
        if (H5Dwrite(dsid, UC_DATATYPE, m_sid, f_sid, H5P_DEFAULT, buffer) < 0) {
            HDfprintf(stderr, "Failed H5Dwrite\n");
            return -1;
        }

        /* Uncork the dataset's metadata from the cache, if SWMR is enabled */
        if (opts->use_swmr) {
            if (H5Oenable_mdc_flushes(dsid) < 0) {
                HDfprintf(stderr, "H5Oenable_mdc_flushes failed\n");
                return -1;
            }
        }

        /* flush file to make the just written plane available. */
        if (H5Dflush(dsid) < 0) {
            HDfprintf(stderr, "Failed to H5Fflush file\n");
            return -1;
        }
    } /* end for each plane to write */

    /* Done writing. Free/Close all resources including data file */
    HDfree(buffer);
    if (H5Dclose(dsid) < 0) {
        HDfprintf(stderr, "Failed to close datasete\n");
        return -1;
    }
    if (H5Sclose(m_sid) < 0) {
        HDfprintf(stderr, "Failed to close memory space\n");
        return -1;
    }
    if (H5Sclose(f_sid) < 0) {
        HDfprintf(stderr, "Failed to close file space\n");
        return -1;
    }

    return 0;
} /* end write_uc_file() */

/* ----------------------------------------------------------------------------
 * Read planes from the dataset.
 * It expects the dataset is being changed (growing).
 * It checks the unlimited dimension (1st one). When it increases,
 * it will read in the new planes, one by one, and verify the data correctness.
 * (The nth plan should contain all "n".)
 * When the unlimited dimension grows to the chunksize (it becomes a cube),
 * that is the expected end of data, the reader exits.
 *
 * Return: 0 succeed; -1 fail.
 * ----------------------------------------------------------------------------
 */
int
read_uc_file(hbool_t towait, options_t * opts)
{
    hid_t     fid;                          /* File ID for new HDF5 file */
    hid_t     dsid;                         /* dataset ID */
    UC_CTYPE *buffer, *bufptr;              /* read data buffer */
    hid_t     f_sid;                        /* dataset file space id */
    hid_t     m_sid;                        /* memory space id */
    int       rank;                         /* rank */
    hsize_t   dims[3];                      /* Dataspace dimensions */
    hsize_t   memdims[3];                   /* Memory space dimensions */
    hsize_t   nplane=0, nplanes_seen=0;     /* nth plane, last nth plane */
    hsize_t   start[3] = {0,0,0}, count[3]; /* Hyperslab selection values */
    hsize_t   j, k;
    int       nreadererr=0;
    int       nerrs;
    int       loops_waiting_for_plane;

    /* Before reading, wait for the message that H5Fopen is complete--file lock is released */
    if (towait && h5_wait_message(WRITER_MESSAGE) < 0) {
        HDfprintf(stderr, "Cannot find writer message file...failed\n");
        return -1;
    }

    HDfprintf(stderr, "Opening to read %s\n", opts->filename);
    if ((fid = H5Fopen(opts->filename, H5F_ACC_RDONLY | (opts->use_swmr ? H5F_ACC_SWMR_READ : 0), opts->fapl_id)) < 0) {
        HDfprintf(stderr, "H5Fopen failed\n");
        return -1;
    }

    if ((dsid = H5Dopen2(fid, opts->progname, H5P_DEFAULT)) < 0) {
        HDfprintf(stderr, "H5Dopen2 failed\n");
        return -1;
    }

    /* Allocate space for data buffer 1 X dims[1] X dims[2] of UC_CTYPE */
    memdims[0] = 1;
    memdims[1] = opts->dims[1];
    memdims[2] = opts->dims[2];
    if ((buffer=(UC_CTYPE*)HDmalloc((size_t)memdims[1]*(size_t)memdims[2]*sizeof(UC_CTYPE)))==NULL) {
        HDfprintf(stderr, "malloc: failed\n");
        return -1;
    }

    /*
     * Get dataset rank and dimension.
     * Verify dimension is as expected (unlimited,2*chunksize,2*chunksize).
     */
    f_sid = H5Dget_space(dsid);    /* Get filespace handle first. */
    rank  = H5Sget_simple_extent_ndims(f_sid);
    if (rank != UC_RANK) {
        HDfprintf(stderr, "rank(%d) of dataset does not match\n", rank);
        return -1;
    }
    if (H5Sget_simple_extent_dims(f_sid, dims, NULL) < 0) {
        HDfprintf(stderr, "H5Sget_simple_extent_dims got error\n");
        return -1;
    }
    HDprintf("dataset rank %d, dimensions %llu x %llu x %llu\n",
            rank, (unsigned long long)(dims[0]), (unsigned long long)(dims[1]),
            (unsigned long long)(dims[2]));
    /* verify that file space dims are as expected and are consistent with memory space dims */
    if (dims[1] != memdims[1] || dims[2] != memdims[2]) {
        HDfprintf(stderr, "dataset dimension is not as expected. Got dims=(%llu,%llu,%llu)\n",
            (unsigned long long)dims[0], (unsigned long long)dims[1],
            (unsigned long long)dims[2]);
        HDfprintf(stderr, "But memdims=(%llu,%llu,%llu)\n",
            (unsigned long long)memdims[0], (unsigned long long)memdims[1],
            (unsigned long long)memdims[2]);
        return -1;
    }

    /* Setup mem-space for buffer */
    if ((m_sid=H5Screate_simple(rank, memdims, NULL)) < 0) {
        HDfprintf(stderr, "H5Screate_simple for memory failed\n");
        return -1;
    }

    /* Read 1 plane at a time whenever the dataset grows larger (along dim[0]) */
    count[0] = 1;
    count[1] = dims[1];
    count[2] = dims[2];
    /* quit when all nplanes  have been read */
    loops_waiting_for_plane=0;
    while (nplanes_seen < opts->nplanes) {
        /* print progress message according to if new planes are availalbe */
        if (nplanes_seen < dims[0]) {
            if (loops_waiting_for_plane) {
                /* end the previous message */
                HDprintf("\n");
                loops_waiting_for_plane=0;
            }
            HDprintf("reading planes %llu to %llu\n", (unsigned long long)nplanes_seen,
                (unsigned long long)dims[0]);
        }
        else {
            if (loops_waiting_for_plane) {
                HDprintf(".");
                if (loops_waiting_for_plane>=30) {
                    HDfprintf(stderr, "waited too long for new plane, quit.\n");
                    return -1;
                }
            }
            else {
                /* print mesg only the first time; dots still no new plane */
                HDprintf("waiting for new planes to read ");
            }
            loops_waiting_for_plane++;
            /* pause for a second */
            HDsleep(1);
        }

        for (nplane=nplanes_seen; nplane < dims[0]; nplane++) {
            /* read planes between last old nplanes and current extent */
            /* Get the dataset's dataspace */
            if ((f_sid = H5Dget_space(dsid)) < 0) {
                HDfprintf(stderr, "H5Dget_space failed\n");
                return -1;
            }

            start[0]=nplane;
            /* Choose the next plane to read */
            if (H5Sselect_hyperslab(f_sid, H5S_SELECT_SET, start, NULL, count, NULL) < 0) {
                HDfprintf(stderr, "H5Sselect_hyperslab failed\n");
                return -1;
            }

            /* Read the plane from the dataset */
            if (H5Dread(dsid, UC_DATATYPE, m_sid, f_sid, H5P_DEFAULT, buffer) < 0) {
                HDfprintf(stderr, "H5Dread failed\n");
                return -1;
            }

            /* compare read data with expected data value which is nplane */
            bufptr = buffer;
            nerrs=0;
            for (j=0; j < dims[1]; j++) {
                for (k=0; k < dims[2]; k++) {
                    if ((hsize_t)*bufptr++ != nplane) {
                        if (++nerrs < ErrorReportMax) {
                            HDfprintf(stderr,
                                "found error %llu plane(%llu,%llu), expected %llu, got %d\n",
                                (unsigned long long)nplane, (unsigned long long)j,
                                (unsigned long long)k, (unsigned long long)nplane, (int)*(bufptr-1));
                        } /* end if should print error */
                    } /* end if value mismatch */
                } /* end for plane second dimension */
            } /* end for plane first dimension */
            if (nerrs) {
                nreadererr++;
                HDfprintf(stderr, "found %d unexpected values in plane %llu\n", nerrs,
                    (unsigned long long)nplane);
            }
        } /* end for each plane added since last read */

        nplanes_seen=dims[0];

        /* check if dataset has grown since last time (update dims) */
        H5Drefresh(dsid);
        f_sid = H5Dget_space(dsid);    /* Get filespace handle first. */
        if (H5Sget_simple_extent_dims(f_sid, dims, NULL) < 0) {
            HDfprintf(stderr, "H5Sget_simple_extent_dims got error\n");
            return -1;
        }
    } /* end while (expecting more planes to read) */

    if (H5Fclose(fid) < 0) {
        HDfprintf(stderr, "H5Fclose failed\n");
        return -1;
    }

    if (nreadererr)
        return -1;
    else
        return 0;
} /* end read_uc_file() */

#endif /* H5_HAVE_FORK */