path: root/src/H5Dvirtual.c

/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
 * 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 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://hdfgroup.org/HDF5/doc/Copyright.html.  If you do not have          *
 * access to either file, you may request a copy from help@hdfgroup.org.     *
 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */

/*
 * Programmer:  Neil Fortner <nfortne2@hdfgroup.org>
 *              Wednesday, January 28, 2015
 *
 * Purpose:
 *      VDSINC
 */

/****************/
/* Module Setup */
/****************/

#define H5D_PACKAGE             /* Suppress error about including H5Dpkg */


/***********/
/* Headers */
/***********/
#include "H5private.h"          /* Generic Functions                    */
#include "H5Dpkg.h"             /* Dataset functions                    */
#include "H5Eprivate.h"         /* Error handling                       */
#include "H5Fprivate.h"         /* Files                                */
#include "H5Gprivate.h"         /* Groups                               */
#include "H5HGprivate.h"        /* Global Heaps                         */
#include "H5MMprivate.h"        /* Memory management                    */
#include "H5Oprivate.h"         /* Object headers                       */
#include "H5Sprivate.h"         /* Dataspaces                           */


/****************/
/* Local Macros */
/****************/


/******************/
/* Local Typedefs */
/******************/


/********************/
/* Local Prototypes */
/********************/

/* Layout operation callbacks */
static herr_t H5D__virtual_construct(H5F_t *f, H5D_t *dset);
static herr_t H5D__virtual_io_init(const H5D_io_info_t *io_info,
    const H5D_type_info_t *type_info, hsize_t nelmts, const H5S_t *file_space,
    const H5S_t *mem_space, H5D_chunk_map_t *cm);
static herr_t H5D__virtual_read(H5D_io_info_t *io_info, const H5D_type_info_t
    *type_info, hsize_t nelmts, const H5S_t *file_space, const H5S_t *mem_space,
    H5D_chunk_map_t *fm);
static herr_t H5D__virtual_write(H5D_io_info_t *io_info,
    const H5D_type_info_t *type_info, hsize_t nelmts, const H5S_t *file_space,
    const H5S_t *mem_space, H5D_chunk_map_t *fm);
static herr_t H5D__virtual_flush(H5D_t *dset, hid_t dxpl_id);

/* Other functions */
static herr_t H5D__virtual_open_source_dset(const H5D_t *vdset,
    H5O_storage_virtual_ent_t *virtual_ent, hid_t dxpl_id);


/*********************/
/* Package Variables */
/*********************/

/* Contiguous storage layout I/O ops */
const H5D_layout_ops_t H5D_LOPS_VIRTUAL[1] = {{
    H5D__virtual_construct,
    NULL,
    H5D__virtual_is_space_alloc,
    H5D__virtual_io_init,
    H5D__virtual_read,
    H5D__virtual_write,
#ifdef H5_HAVE_PARALLEL
    H5D__virtual_collective_read, //VDSINC
    H5D__virtual_collective_write, //VDSINC
#endif /* H5_HAVE_PARALLEL */
    NULL,
    NULL,
    H5D__virtual_flush,
    NULL
}};


/*******************/
/* Local Variables */
/*******************/



/*-------------------------------------------------------------------------
 * Function:    H5D__virtual_copy_layout
 *
 * Purpose:     Deep copies virtual storage layout message in memory.
 *              This function assumes that the top-level struct has
 *              already been copied (so the source struct retains
 *              ownership of the fields passed to this function).
 *
 * Return:      Non-negative on success/Negative on failure
 *
 * Programmer:  Neil Fortner
 *              February 10, 2015
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5D__virtual_copy_layout(H5O_layout_t *layout)
{
    H5O_storage_virtual_ent_t *orig_list = NULL;
    size_t          i;
    herr_t          ret_value = SUCCEED;

    FUNC_ENTER_PACKAGE

    HDassert(layout);
    HDassert(layout->type == H5D_VIRTUAL);

    if(layout->storage.u.virt.list_nused > 0) {
        HDassert(layout->storage.u.virt.list);

        /* Save original entry list for use as the "source" */
        orig_list = layout->storage.u.virt.list;

        /* Allocate memory for the list */
        if(NULL == (layout->storage.u.virt.list = (H5O_storage_virtual_ent_t *)H5MM_calloc(layout->storage.u.virt.list_nused * sizeof(H5O_storage_virtual_ent_t))))
            HGOTO_ERROR(H5E_DATASET, H5E_NOSPACE, FAIL, "unable to allocate memory for virtual dataset entry list")
        layout->storage.u.virt.list_nalloc = layout->storage.u.virt.list_nused;

        /* Copy the list entries, though set source_dset to NULL */
        for(i = 0; i < layout->storage.u.virt.list_nused; i++) {
            if(NULL == (layout->storage.u.virt.list[i].source_file_name
                    = HDstrdup(orig_list[i].source_file_name)))
                HGOTO_ERROR(H5E_DATASET, H5E_RESOURCE, FAIL, "unable to duplicate source file name")
            if(NULL == (layout->storage.u.virt.list[i].source_dset_name
                    = HDstrdup(orig_list[i].source_dset_name)))
                HGOTO_ERROR(H5E_DATASET, H5E_RESOURCE, FAIL, "unable to duplicate source dataset name")
            if(NULL == (layout->storage.u.virt.list[i].source_select
                    = H5S_copy(orig_list[i].source_select, FALSE, TRUE)))
                HGOTO_ERROR(H5E_DATASET, H5E_CANTCOPY, FAIL, "unable to copy source selection")
            if(NULL == (layout->storage.u.virt.list[i].virtual_select
                    = H5S_copy(orig_list[i].virtual_select, FALSE, TRUE)))
                HGOTO_ERROR(H5E_DATASET, H5E_CANTCOPY, FAIL, "unable to copy virtual selection")
            layout->storage.u.virt.list[i].source_dset = NULL;
            layout->storage.u.virt.list[i].unlim_dim_source = orig_list[i].unlim_dim_source;
            layout->storage.u.virt.list[i].unlim_dim_virtual = orig_list[i].unlim_dim_virtual;
            layout->storage.u.virt.list[i].unlim_extent_source = orig_list[i].unlim_extent_source;
            layout->storage.u.virt.list[i].unlim_extent_virtual = orig_list[i].unlim_extent_virtual;
            layout->storage.u.virt.list[i].clip_size_source = orig_list[i].clip_size_source;
            layout->storage.u.virt.list[i].clip_size_virtual = orig_list[i].clip_size_virtual;
            layout->storage.u.virt.list[i].source_space_status = orig_list[i].source_space_status;
            layout->storage.u.virt.list[i].virtual_space_status = orig_list[i].virtual_space_status;
        } /* end for */
    } /* end if */
    else {
        HDassert(0 && "checking code coverage...");//VDSINC
        /* Zero out other fields related to list, just to be sure */
        layout->storage.u.virt.list = NULL;
        layout->storage.u.virt.list_nalloc = 0;
    } /* end else */

done:
    /* Release allocated resources on failure */
    if((ret_value < 0) && orig_list
            && (orig_list != layout->storage.u.virt.list))
        if(H5D__virtual_reset_layout(layout) < 0)
            HDONE_ERROR(H5E_DATASET, H5E_CANTFREE, FAIL, "unable to reset virtual layout")

    FUNC_LEAVE_NOAPI(ret_value)
} /* end H5D__virtual_copy_layout() */


/*-------------------------------------------------------------------------
 * Function:    H5D_virtual_update_min_dims
 *
 * Purpose:     Updates the virtual layout's "min_dims" field to take into
 *              account the "idx"th entry in the mapping list.  The entry
 *              must be complete, though top level fields list_nused does
 *              (and of course min_dims) do not need to take it into
 *              account.
 *
 * Return:      Non-negative on success/Negative on failure
 *
 * Programmer:  Neil Fortner
 *              February 10, 2015
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5D_virtual_update_min_dims(H5O_layout_t *layout, size_t idx)
{
    H5S_sel_type    sel_type;
    int             rank;
    hsize_t         bounds_start[H5S_MAX_RANK];
    hsize_t         bounds_end[H5S_MAX_RANK];
    int             i;
    herr_t          ret_value = SUCCEED;

    FUNC_ENTER_NOAPI(FAIL)

    HDassert(layout);
    HDassert(layout->type == H5D_VIRTUAL);
    HDassert(idx < layout->storage.u.virt.list_nalloc);

    /* Get type of selection */
    if(H5S_SEL_ERROR == (sel_type = H5S_GET_SELECT_TYPE(layout->storage.u.virt.list[idx].virtual_select)))
        HGOTO_ERROR(H5E_DATASET, H5E_CANTGET, FAIL, "unable to get selection type")

    /* Do not update min_dims for "all" or "none" selections */
    if((sel_type == H5S_SEL_ALL) || (sel_type == H5S_SEL_NONE))
        HGOTO_DONE(SUCCEED)

    /* Get rank of vspace */
    if((rank = H5S_GET_EXTENT_NDIMS(layout->storage.u.virt.list[idx].virtual_select)) < 0)
        HGOTO_ERROR(H5E_DATASET, H5E_CANTGET, FAIL, "unable to get number of dimensions")

    /* Get selection bounds */
    if(H5S_SELECT_BOUNDS(layout->storage.u.virt.list[idx].virtual_select, bounds_start, bounds_end) < 0)
        HGOTO_ERROR(H5E_DATASET, H5E_CANTGET, FAIL, "unable to get selection bounds")

    /* Update min_dims */
    for(i = 0; i < rank; i++)
        /* Don't check unlimited dimensions in the selection */
        if((i != layout->storage.u.virt.list[idx].unlim_dim_virtual)
                && (bounds_end[i] > layout->storage.u.virt.min_dims[i]))
            layout->storage.u.virt.min_dims[i] = bounds_end[i];

done:
    FUNC_LEAVE_NOAPI(ret_value)
} /* end H5D_virtual_update_min_dims() */


/*-------------------------------------------------------------------------
 * Function:    H5D__virtual_open_source_dset
 *
 * Purpose:     Attempts to open a source dataset.
 *
 * Return:      Non-negative on success/Negative on failure
 *
 * Programmer:  Neil Fortner
 *              March 6, 2015
 *
 *-------------------------------------------------------------------------
 */
static herr_t
H5D__virtual_open_source_dset(const H5D_t *vdset,
    H5O_storage_virtual_ent_t *virtual_ent, hid_t dxpl_id)
{
    H5F_t       *src_file = NULL;       /* Source file */
    hbool_t     src_file_open = FALSE;  /* Whether we have opened and need to close src_file */
    H5G_loc_t   src_root_loc;           /* Object location of source file root group */
    herr_t      ret_value = SUCCEED;    /* Return value */

    FUNC_ENTER_STATIC

    /* Sanity check */
    HDassert(virtual_ent);
    HDassert(!virtual_ent->source_dset);

    /* Get dapl and fapl from current (virtual dataset) location? VDSINC */
    /* Write code to check if these exist and return without opening dset
     * otherwise VDSINC */

    /* Check if we need to open the source file */
    if(HDstrcmp(virtual_ent->source_file_name, ".")) {
        /* Open the source file */
        if(NULL == (src_file = H5F_open(virtual_ent->source_file_name, H5F_INTENT(vdset->oloc.file) & H5F_ACC_RDWR, H5P_FILE_CREATE_DEFAULT, H5P_FILE_ACCESS_DEFAULT, dxpl_id)))
            HGOTO_ERROR(H5E_DATASET, H5E_CANTOPENFILE, FAIL, "unable to open source file")
        src_file_open = TRUE;
    } /* end if */
    else
        /* Source file is ".", use the virtual dataset's file */
        src_file = vdset->oloc.file;

    /* Set up the root group in the destination file */
    if(NULL == (src_root_loc.oloc = H5G_oloc(H5G_rootof(src_file))))
        HGOTO_ERROR(H5E_DATASET, H5E_BADVALUE, FAIL, "unable to get object location for root group")
    if(NULL == (src_root_loc.path = H5G_nameof(H5G_rootof(src_file))))
        HGOTO_ERROR(H5E_DATASET, H5E_BADVALUE, FAIL, "unable to get path for root group")

    /* Open the source dataset */
    if(NULL == (virtual_ent->source_dset = H5D__open_name(&src_root_loc, virtual_ent->source_dset_name, H5P_DATASET_ACCESS_DEFAULT, dxpl_id)))
        HGOTO_ERROR(H5E_DATASET, H5E_CANTOPENOBJ, FAIL, "unable to open dataset")

    /* Patch the source selection if necessary */
    if(virtual_ent->source_space_status != H5O_VIRTUAL_STATUS_CORRECT) {
        if(H5S_extent_copy(virtual_ent->source_select, virtual_ent->source_dset->shared->space) < 0)
            HGOTO_ERROR(H5E_DATASET, H5E_CANTCOPY, FAIL, "can't copy source dataspace extent")
        virtual_ent->source_space_status = H5O_VIRTUAL_STATUS_CORRECT;
    } /* end if */

done:
    /* Close source file */
    if(src_file_open)
        if(H5F_try_close(src_file) < 0)
            HDONE_ERROR(H5E_DATASET, H5E_CANTCLOSEFILE, FAIL, "can't close source file")

    FUNC_LEAVE_NOAPI(ret_value)
} /* end H5D__virtual_open_source_dset() */


/*-------------------------------------------------------------------------
 * Function:    H5D__virtual_set_extent_unlim
 *
 * Purpose:     Sets the extent of the virtual dataset by checking the
 *              extents of source datasets where an unlimited selection
 *              matching.  Dimensions that are not unlimited in any
 *              virtual mapping selections are not affected.
 *
 * Return:      Non-negative on success/Negative on failure
 *
 * Programmer:  Neil Fortner
 *              April 22, 2015
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5D__virtual_set_extent_unlim(const H5D_t *dset, hid_t dxpl_id)
{
    H5O_storage_virtual_t *storage;
    hsize_t     new_dims[H5S_MAX_RANK];
    hsize_t     curr_dims[H5S_MAX_RANK];
    hsize_t     clip_size;
    int         rank;
    hbool_t     changed = FALSE;        /* Whether the VDS extent changed */
    size_t      i;
    herr_t      ret_value = SUCCEED;    /* Return value */

    FUNC_ENTER_PACKAGE

    /* Sanity check */
    HDassert(dset);
    storage = &dset->shared->layout.storage.u.virt;
    HDassert(dset->shared->layout.storage.type == H5D_VIRTUAL);

    /* Get rank of VDS */
    if((rank = H5S_GET_EXTENT_NDIMS(dset->shared->space)) < 0)
        HGOTO_ERROR(H5E_DATASET, H5E_CANTGET, FAIL, "unable to get number of dimensions")

    /* Initialize new_dims to HSIZE_UNDEF */
    for(i = 0; i < (size_t)rank; i++)
        new_dims[i] = HSIZE_UNDEF;

    /* Iterate over mappings */
    for(i = 0; i < storage->list_nalloc; i++)
        /* Check for unlimited dimension */
        if(storage->list[i].unlim_dim_virtual >= 0) {
            HDassert(storage->list[i].unlim_dim_source >= 0);

            /* Open source dataset */
            if(!storage->list[i].source_dset)
                if(H5D__virtual_open_source_dset(dset, &storage->list[i], dxpl_id) < 0)
                    HGOTO_ERROR(H5E_DATASET, H5E_CANTOPENOBJ, FAIL, "unable to open source dataset")

            /* Check if source dataset is open */
            if(storage->list[i].source_dset) {
                /* Retrieve current source dataset extent and patch mapping.
                 * Note this will clip the source selection to the extent. */
                if(H5S_extent_copy(storage->list[i].source_select, storage->list[i].source_dset->shared->space) < 0)
                    HGOTO_ERROR(H5E_DATASET, H5E_CANTCOPY, FAIL, "can't copy source dataspace extent")

                /* Get source space dimenstions */
                if(H5S_get_simple_extent_dims(storage->list[i].source_select, curr_dims, NULL) < 0)
                    HGOTO_ERROR(H5E_DATASET, H5E_CANTGET, FAIL, "can't get source space dimensions")

                /* Check if the source extent in the unlimited dimension
                 * changed since the last time the VDS extent/mapping
                 * was updated */
                if(curr_dims[storage->list[i].unlim_dim_source]
                        == storage->list[i].unlim_extent_source)
                    /* Use cached result for clip size */
                    clip_size = storage->list[i].clip_size_virtual;
                else {
                    /* Get size that virtual selection would be clipped
                     * to to match size of source selection */
                    if(H5S_hyper_get_clip_extent(storage->list[i].virtual_select, storage->list[i].source_select, &clip_size) < 0)
                        HGOTO_ERROR(H5E_DATASET, H5E_CANTGET, FAIL, "can't get hyperslab clip size")

                    /* If we are setting the extent by the maximum of all
                     * mappings, clip virtual_select.  Note that if we used the
                     * cached clip_size above, the selection will already be
                     * clipped to the correct size. */
                    if(storage->set_extent_max)
                        if(H5S_hyper_clip_unlim(storage->list[i].virtual_select, clip_size))
                            HGOTO_ERROR(H5E_DATASET, H5E_CANTCLIP, FAIL, "failed to clip unlimited selection")

                    /* Update cached values unlim_extent_source and
                     * clip_size_virtual */
                    storage->list[i].unlim_extent_source = curr_dims[storage->list[i].unlim_dim_source];
                    storage->list[i].clip_size_virtual = clip_size;
                } /* end else */

                /* Update new_dims */
                if((new_dims[storage->list[i].unlim_dim_virtual] == HSIZE_UNDEF)
                        || (storage->set_extent_max ? (clip_size
                        > (hsize_t)new_dims[storage->list[i].unlim_dim_virtual])
                        : (clip_size
                        < (hsize_t)new_dims[storage->list[i].unlim_dim_virtual])))
                    new_dims[storage->list[i].unlim_dim_virtual] = clip_size;
            } /* end if */
        } /* end if */

    /* Get current VDS dimensions */
    if(H5S_get_simple_extent_dims(dset->shared->space, curr_dims, NULL) < 0)
        HGOTO_ERROR(H5E_DATASET, H5E_CANTGET, FAIL, "can't get VDS dimensions")

    /* Calculate new extent */
    for(i = 0; i < (size_t)rank; i++) {
        if((new_dims[i] != HSIZE_UNDEF) && (new_dims[i] != curr_dims[i])) {
            changed = TRUE;
            curr_dims[i] = new_dims[i];
        } /* end if */
        if(storage->min_dims[i] > curr_dims[i]) {
            HDassert(0 && "Checking code coverage..."); //VDSINC
            changed = TRUE;
            curr_dims[i] = storage->min_dims[i];
        } /* end if */
    } /* end for */

    /* If we did not change the VDS dimensions and we are setting the extent by
     * maximum, there is nothing more to update */
    if(changed || !storage->set_extent_max) {
        /* Update VDS extent */
        if(changed)
            if(H5S_set_extent(dset->shared->space, curr_dims) < 0)
                HGOTO_ERROR(H5E_DATASET, H5E_CANTINIT, FAIL, "unable to modify size of data space")

        /* Iterate over mappings again to update source selections and virtual
         * mapping extents */
        for(i = 0; i < storage->list_nalloc; i++)
            /* Check for unlimited dimension */
            if((storage->list[i].unlim_dim_source >= 0)
                    && (storage->list[i].source_dset)) {
                HDassert(storage->list[i].unlim_dim_virtual >= 0);

                /* Update virtual mapping extent.  Note this function does not
                 * clip the selection. */
                if(changed)
                    if(H5S_set_extent(storage->list[i].virtual_select, curr_dims) < 0)
                        HGOTO_ERROR(H5E_DATASET, H5E_CANTINIT, FAIL, "unable to modify size of data space")

                /* Check if we are setting extent by the minimum of mappings */
                if(!storage->set_extent_max) {
                    /* Clip virtual selection to extent (only necessary if the
                     * extent changed, otherwise it will already be clipped to
                     * the extent) */
                    if(changed) {
                        HDassert(0 && "Checking code coverage..."); //VDSINC
                        if(H5S_hyper_clip_to_extent(storage->list[i].virtual_select))
                            HGOTO_ERROR(H5E_DATASET, H5E_CANTCLIP, FAIL, "failed to clip unlimited selection")
                    } //VDSINC

                    /* Check if the virtual extent in the unlimited dimension
                     * changed since the last time the VDS extent/mapping was
                     * updated */
                    if(curr_dims[storage->list[i].unlim_dim_virtual]
                            == storage->list[i].unlim_extent_virtual) {
                        HDassert(0 && "Checking code coverage..."); //VDSINC
                        /* Use cached result for clip size */
                        clip_size = storage->list[i].clip_size_source;
                    } //VDSINC
                    else {
                        HDassert(0 && "Checking code coverage..."); //VDSINC
                        /* Get size that source selection will be clipped to to
                         * match size of virtual selection */
                        if(H5S_hyper_get_clip_extent(storage->list[i].source_select, storage->list[i].virtual_select, &clip_size) < 0)
                            HGOTO_ERROR(H5E_DATASET, H5E_CANTGET, FAIL, "can't get hyperslab clip size")

                        /* Update cached values unlim_extent_virtual and
                         * clip_size_source */
                        storage->list[i].unlim_extent_virtual = curr_dims[storage->list[i].unlim_dim_virtual];
                        storage->list[i].clip_size_source = clip_size;
                    } /* end else */

                    /* Clip source_select */
                    if(H5S_hyper_clip_unlim(storage->list[i].source_select, clip_size))
                        HGOTO_ERROR(H5E_DATASET, H5E_CANTCLIP, FAIL, "failed to clip unlimited selection")
                } /* end if */
            } /* end if */
    } /* end if */

    /* Call H5D__mark so dataspace is updated on disk? VDSINC */

done:
    FUNC_LEAVE_NOAPI(ret_value)
} /* end H5D__virtual_set_extent_unlim() */


/*-------------------------------------------------------------------------
 * Function:    H5D__virtual_reset_layout
 *
 * Purpose:     Frees internal structures in a virtual storage layout
 *              message in memory.  This function is safe to use on
 *              incomplete structures (for recovery from failure) provided
 *              the internal structures are initialized with all bytes set
 *              to 0.
 *
 * Return:      Non-negative on success/Negative on failure
 *
 * Programmer:  Neil Fortner
 *              February 11, 2015
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5D__virtual_reset_layout(H5O_layout_t *layout)
{
    size_t          i;
    herr_t          ret_value = SUCCEED;

    FUNC_ENTER_PACKAGE

    HDassert(layout);
    HDassert(layout->type == H5D_VIRTUAL);

    /* Free the list entries.  Note we always attempt to free everything even in
     * the case of a failure. */
    for(i = 0; i < layout->storage.u.virt.list_nused; i++) {
        layout->storage.u.virt.list[i].source_file_name = (char *)H5MM_xfree(layout->storage.u.virt.list[i].source_file_name);
        layout->storage.u.virt.list[i].source_dset_name = (char *)H5MM_xfree(layout->storage.u.virt.list[i].source_dset_name);
        if(layout->storage.u.virt.list[i].source_select
                && H5S_close(layout->storage.u.virt.list[i].source_select) < 0)
            HDONE_ERROR(H5E_DATASET, H5E_CLOSEERROR, FAIL, "unable to release source selection")
        layout->storage.u.virt.list[i].source_select = NULL;
        if(layout->storage.u.virt.list[i].virtual_select
                && H5S_close(layout->storage.u.virt.list[i].virtual_select) < 0)
            HDONE_ERROR(H5E_DATASET, H5E_CLOSEERROR, FAIL, "unable to release virtual selection")
        layout->storage.u.virt.list[i].virtual_select = NULL;
        /* Close dataset here?  VDSINC */
    } /* end for */

    /* Free the list */
    layout->storage.u.virt.list = (H5O_storage_virtual_ent_t *)H5MM_xfree(layout->storage.u.virt.list);

    /* Note the lack of a done: label.  This is because there are no HGOTO_ERROR
     * calls.  If one is added, a done: label must also be added */
    FUNC_LEAVE_NOAPI(ret_value)
} /* end H5D__virtual_reset_layout() */


/*-------------------------------------------------------------------------
 * Function:    H5D__virtual_delete
 *
 * Purpose:     Delete the file space for a virtual dataset
 *
 * Return:      Non-negative on success/Negative on failure
 *
 * Programmer:  Neil Fortner
 *              February 6, 2015
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5D__virtual_delete(H5F_t *f, hid_t dxpl_id, H5O_storage_t *storage)
{
    herr_t ret_value = SUCCEED;   /* Return value */

    FUNC_ENTER_PACKAGE

    /* check args */
    HDassert(f);
    HDassert(storage);
    HDassert(storage->type == H5D_VIRTUAL);

    /* Need to add stuff for private data here VDSINC */

    /* Delete the global heap block */
    if(H5HG_remove(f, dxpl_id, (H5HG_t *)&(storage->u.virt.serial_list_hobjid)) < 0)
        HGOTO_ERROR(H5E_DATASET, H5E_WRITEERROR, FAIL, "Unable to remove heap object")

    /* Clear global heap ID in storage */
    storage->u.virt.serial_list_hobjid.addr = HADDR_UNDEF;
    storage->u.virt.serial_list_hobjid.idx = 0;

done:
    FUNC_LEAVE_NOAPI(ret_value)
} /* end H5D__virtual_delete */


/*-------------------------------------------------------------------------
 * Function:    H5D__virtual_construct
 *
 * Purpose:     Constructs new virtual layout information for dataset
 *
 * Return:      Non-negative on success/Negative on failure
 *
 * Programmer:  Neil Fortner
 *              Monday, February 2, 2015
 *
 *-------------------------------------------------------------------------
 */
static herr_t
H5D__virtual_construct(H5F_t UNUSED *f, H5D_t *dset)
{
    size_t              i;
    herr_t              ret_value = SUCCEED;

    FUNC_ENTER_STATIC

    HDassert(dset->shared->layout.storage.u.virt.list || (dset->shared->layout.storage.u.virt.list_nused == 0));

    /* Patch the virtual selection dataspaces */
    for(i = 0; i < dset->shared->layout.storage.u.virt.list_nused; i++) {
        HDassert(dset->shared->layout.storage.u.virt.list[i].virtual_space_status == H5O_VIRTUAL_STATUS_USER);
        if(H5S_extent_copy(dset->shared->layout.storage.u.virt.list[i].virtual_select, dset->shared->space) < 0)
            HGOTO_ERROR(H5E_DATASET, H5E_CANTCOPY, FAIL, "can't copy virtual dataspace extent")
        dset->shared->layout.storage.u.virt.list[i].virtual_space_status = H5O_VIRTUAL_STATUS_CORRECT;
    } /* end for */

done:
    FUNC_LEAVE_NOAPI(ret_value)
} /* end H5D__virtual_construct() */


/*-------------------------------------------------------------------------
 * Function:    H5D__virtual_is_space_alloc
 *
 * Purpose:     Query if space is allocated for layout
 *
 * Return:      TRUE if space is allocated
 *              FALSE if it is not
 *              Negative on failure
 *
 * Programmer:  Neil Fortner
 *              February 6, 2015
 *
 *-------------------------------------------------------------------------
 */
hbool_t
H5D__virtual_is_space_alloc(const H5O_storage_t UNUSED *storage)
{
    hbool_t ret_value;                  /* Return value */

    FUNC_ENTER_PACKAGE_NOERR

    /* Need to decide what to do here.  For now just return TRUE VDSINC */
    ret_value = TRUE;//storage->u.virt.serial_list_hobjid.addr != HADDR_UNDEF;

    FUNC_LEAVE_NOAPI(ret_value)
} /* end H5D__virtual_is_space_alloc() */


/*-------------------------------------------------------------------------
 * Function:    H5D__virtual_io_init
 *
 * Purpose:     Performs initialization before any sort of I/O on the raw data
 *
 * Return:      Non-negative on success/Negative on failure
 *
 * Programmer:  Neil Fortner
 *              February 6, 2015
 *
 *-------------------------------------------------------------------------
 */
static herr_t
H5D__virtual_io_init(const H5D_io_info_t UNUSED *io_info, const H5D_type_info_t UNUSED *type_info,
    hsize_t UNUSED nelmts, const H5S_t UNUSED *file_space, const H5S_t UNUSED *mem_space,
    H5D_chunk_map_t UNUSED *cm)
{
    FUNC_ENTER_STATIC_NOERR

    /* No-op for now.  Delete if we never add anything here. VDSINC */

    FUNC_LEAVE_NOAPI(SUCCEED)
} /* end H5D__virtual_io_init() */


/*-------------------------------------------------------------------------
 * Function:    H5D__virtual_read
 *
 * Purpose:     Read from a virtual dataset.
 *
 * Return:      Non-negative on success/Negative on failure
 *
 * Programmer:  Neil Fortner
 *              February 6, 2015
 *
 *-------------------------------------------------------------------------
 */
static herr_t
H5D__virtual_read(H5D_io_info_t *io_info, const H5D_type_info_t *type_info,
    hsize_t UNUSED nelmts, const H5S_t *file_space, const H5S_t *mem_space,
    H5D_chunk_map_t UNUSED *fm)
{
    H5O_storage_virtual_t *storage;         /* Convenient pointer into layout struct */
    H5S_t       *projected_mem_space = NULL; /* Memory space for selection in a single mapping */
    H5S_t       *projected_src_space = NULL; /* File space for selection in a single source dataset */
    hssize_t    select_nelmts;              /* Number of elements in selection */
    size_t      i;                          /* Local index variable */
    herr_t      ret_value = SUCCEED;        /* Return value */

    FUNC_ENTER_STATIC

    /* Sanity check */
    HDassert(io_info);
    HDassert(io_info->u.rbuf);
    HDassert(type_info);
    HDassert(mem_space);
    HDassert(file_space);

    storage = &io_info->dset->shared->layout.storage.u.virt;

    /* Update VDS extent due to unlimited selections */
    /* Don't call if there is no unlimited selection? VDSINC */
    if(H5D__virtual_set_extent_unlim(io_info->dset, io_info->dxpl_id) < 0)
        HGOTO_ERROR(H5E_DATASET, H5E_CANTINIT, FAIL, "unable to update virtual dataset extent")

    /* Iterate over mappings */
    for(i = 0; i < storage->list_nused; i++) {
        /* Sanity check that the virtual space has been patched by now */
        HDassert(storage->list[i].virtual_space_status == H5O_VIRTUAL_STATUS_CORRECT);

        /* Project intersection of file space and mapping virtual space onto
         * memory space */
        if(H5S_select_project_intersection(file_space, mem_space, storage->list[i].virtual_select, &projected_mem_space) < 0)
            HGOTO_ERROR(H5E_DATASET, H5E_CANTCLIP, FAIL, "can't project virtual intersection onto memory space")

        /* Get number of elements in projected dataspace */
        if((select_nelmts = (hssize_t)H5S_GET_SELECT_NPOINTS(projected_mem_space)) < 0)
            HGOTO_ERROR(H5E_DATASET, H5E_CANTCOUNT, FAIL, "unable to get number of elements in selection")

        /* Only perform I/O if there are any elements */
        if(select_nelmts > 0) {
            /* Open source dataset */
            if(!storage->list[i].source_dset)
                /* Try to open dataset */
                if(H5D__virtual_open_source_dset(io_info->dset, &storage->list[i], io_info->dxpl_id) < 0)
                    HGOTO_ERROR(H5E_DATASET, H5E_CANTOPENOBJ, FAIL, "unable to open source dataset")

            /* Check if source dataset is open */
            if(storage->list[i].source_dset) {
                /* Sanity check that the source space has been patched by now */
                HDassert(storage->list[i].source_space_status == H5O_VIRTUAL_STATUS_CORRECT);

                /* Project intersection of file space and mapping virtual space onto
                 * mapping source space */
                if(H5S_select_project_intersection(storage->list[i].virtual_select, storage->list[i].source_select, file_space, &projected_src_space) < 0)
                    HGOTO_ERROR(H5E_DATASET, H5E_CANTCLIP, FAIL, "can't project virtual intersection onto source space")

                /* Perform read on source dataset */
                if(H5D__read(storage->list[i].source_dset, type_info->dst_type_id, projected_mem_space, projected_src_space, io_info->dxpl_id, io_info->u.rbuf) < 0)
                    HGOTO_ERROR(H5E_DATASET, H5E_READERROR, FAIL, "can't read source dataset")

                /* Close projected_src_space */
                if(H5S_close(projected_src_space) < 0)
                    HGOTO_ERROR(H5E_DATASET, H5E_CLOSEERROR, FAIL, "can't close projected source space")
                projected_src_space = NULL;
            } /* end if */
            else
                /* We do not have a source dataset open, fill with fill value */
                HDassert(0 && "Not yet implemented...");//VDSINC
        } /* end if */

        /* Close projected_mem_space */
        if(H5S_close(projected_mem_space) < 0)
            HGOTO_ERROR(H5E_DATASET, H5E_CLOSEERROR, FAIL, "can't close projected memory space")
        projected_mem_space = NULL;
    } /* end for */

    /* Fill unmapped part of buffer with fill value.  Keep track of total number
     * elements written to memory buffer and assert that it == nelmts VDSINC */

done:
    /* Release allocated resources on failure */
    if(projected_src_space) {
        HDassert(ret_value < 0);
        if(H5S_close(projected_src_space) < 0)
            HDONE_ERROR(H5E_DATASET, H5E_CLOSEERROR, FAIL, "can't close projected source space")
    } /* end if */
    if(projected_mem_space) {
        HDassert(ret_value < 0);
        if(H5S_close(projected_mem_space) < 0)
            HDONE_ERROR(H5E_DATASET, H5E_CLOSEERROR, FAIL, "can't close projected memory space")
    } /* end if */

    FUNC_LEAVE_NOAPI(ret_value)
} /* end H5D__virtual_read() */


/*-------------------------------------------------------------------------
 * Function:    H5D__virtual_write
 *
 * Purpose:     Write to a virtual dataset.
 *
 * Return:      Non-negative on success/Negative on failure
 *
 * Programmer:  Neil Fortner
 *              February 6, 2015
 *
 *-------------------------------------------------------------------------
 */
static herr_t
H5D__virtual_write(H5D_io_info_t *io_info, const H5D_type_info_t *type_info,
    hsize_t UNUSED nelmts, const H5S_t *file_space, const H5S_t *mem_space,
    H5D_chunk_map_t UNUSED *fm)
{
    H5O_storage_virtual_t *storage;         /* Convenient pointer into layout struct */
    H5S_t       *projected_mem_space = NULL; /* Memory space for selection in a single mapping */
    H5S_t       *projected_src_space = NULL; /* File space for selection in a single source dataset */
    hssize_t    select_nelmts;              /* Number of elements in selection */
    size_t      i;                          /* Local index variable */
    herr_t      ret_value = SUCCEED;        /* Return value */

    FUNC_ENTER_STATIC

    /* Sanity check */
    HDassert(io_info);
    HDassert(io_info->u.rbuf);
    HDassert(type_info);
    HDassert(mem_space);
    HDassert(file_space);

    storage = &io_info->dset->shared->layout.storage.u.virt;

    /* Update VDS extent due to unlimited selections */
    /* Don't call if there is no unlimited selection? VDSINC */
    if(H5D__virtual_set_extent_unlim(io_info->dset, io_info->dxpl_id) < 0)
        HGOTO_ERROR(H5E_DATASET, H5E_CANTINIT, FAIL, "unable to update virtual dataset extent")

    /* Iterate over mappings */
    for(i = 0; i < storage->list_nused; i++) {
        /* Sanity check that virtual space has been patched by now */
        HDassert(storage->list[i].virtual_space_status == H5O_VIRTUAL_STATUS_CORRECT);

        /* Project intersection of file space and mapping virtual space onto
         * memory space */
        if(H5S_select_project_intersection(file_space, mem_space, storage->list[i].virtual_select, &projected_mem_space) < 0)
            HGOTO_ERROR(H5E_DATASET, H5E_CANTCLIP, FAIL, "can't project virtual intersection onto memory space")

        /* Get number of elements in projected dataspace */
        if((select_nelmts = (hssize_t)H5S_GET_SELECT_NPOINTS(projected_mem_space)) < 0)
            HGOTO_ERROR(H5E_DATASET, H5E_CANTCOUNT, FAIL, "unable to get number of elements in selection")

        /* Only perform I/O if there are any elements */
        if(select_nelmts > 0) {
            /* Open source dataset, fail if cannot open */
            if(!storage->list[i].source_dset) {
                //VDSINC check all source datasets before any I/O
                if(H5D__virtual_open_source_dset(io_info->dset, &storage->list[i], io_info->dxpl_id) < 0)
                    HGOTO_ERROR(H5E_DATASET, H5E_CANTOPENOBJ, FAIL, "unable to open source dataset")
                if(!storage->list[i].source_dset)
                    HGOTO_ERROR(H5E_DATASET, H5E_CANTOPENOBJ, FAIL, "did not open source dataset")
            } /* end if */

            /* Sanity check that source space has been patched by now */
            HDassert(storage->list[i].source_space_status == H5O_VIRTUAL_STATUS_CORRECT);

            /* Extend source dataset if necessary and there is an unlimited
             * dimension VDSINC */
            /* Project intersection of file space and mapping virtual space onto
             * mapping source space */
            if(H5S_select_project_intersection(storage->list[i].virtual_select, storage->list[i].source_select, file_space, &projected_src_space) < 0)
                HGOTO_ERROR(H5E_DATASET, H5E_CANTCLIP, FAIL, "can't project virtual intersection onto source space")

            /* Perform read on source dataset */
            if(H5D__write(storage->list[i].source_dset, type_info->dst_type_id, projected_mem_space, projected_src_space, io_info->dxpl_id, io_info->u.wbuf) < 0)
                HGOTO_ERROR(H5E_DATASET, H5E_WRITEERROR, FAIL, "can't write to source dataset")

            /* Close projected_src_space */
            if(H5S_close(projected_src_space) < 0)
                HGOTO_ERROR(H5E_DATASET, H5E_CLOSEERROR, FAIL, "can't close projected source space")
            projected_src_space = NULL;
        } /* end if */

        /* Close projected_mem_space */
        if(H5S_close(projected_mem_space) < 0)
            HGOTO_ERROR(H5E_DATASET, H5E_CLOSEERROR, FAIL, "can't close projected memory space")
        projected_mem_space = NULL;
    } /* end for */

done:
    /* Release allocated resources on failure */
    if(projected_src_space) {
        HDassert(ret_value < 0);
        if(H5S_close(projected_src_space) < 0)
            HDONE_ERROR(H5E_DATASET, H5E_CLOSEERROR, FAIL, "can't close projected source space")
    } /* end if */
    if(projected_mem_space) {
        HDassert(ret_value < 0);
        if(H5S_close(projected_mem_space) < 0)
            HDONE_ERROR(H5E_DATASET, H5E_CLOSEERROR, FAIL, "can't close projected memory space")
    } /* end if */

    FUNC_LEAVE_NOAPI(ret_value)
} /* end H5D__virtual_write() */


/*-------------------------------------------------------------------------
 * Function:    H5D__virtual_flush
 *
 * Purpose:     Writes all dirty data to disk.
 *
 * Return:      Non-negative on success/Negative on failure
 *
 * Programmer:  Neil Fortner
 *              February 6, 2015
 *
 *-------------------------------------------------------------------------
 */
static herr_t
H5D__virtual_flush(H5D_t UNUSED *dset, hid_t UNUSED dxpl_id)
{
    FUNC_ENTER_STATIC_NOERR

    /* Flush only open datasets */
    /* No-op for now VDSINC */

    FUNC_LEAVE_NOAPI(SUCCEED)
} /* end H5D__virtual_flush() */


/*-------------------------------------------------------------------------
 * Function:    H5D__virtual_copy
 *
 * Purpose:     Copy virtual storage raw data from SRC file to DST file.
 *
 * Return:      Non-negative on success/Negative on failure
 *
 * Programmer:  Neil Fortner
 *              February 6, 2015
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5D__virtual_copy(H5F_t UNUSED *f_src, const H5O_storage_virtual_t UNUSED *storage_src,
    H5F_t UNUSED *f_dst, H5O_storage_virtual_t UNUSED *storage_dst, H5T_t UNUSED *dt_src,
    H5O_copy_t UNUSED *cpy_info, hid_t UNUSED dxpl_id)
{
    FUNC_ENTER_PACKAGE_NOERR

    HDassert(0 && "Not yet implemented...");//VDSINC

    FUNC_LEAVE_NOAPI(SUCCEED)
} /* end H5D__virtual_copy() */