/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
* Copyright by The HDF Group. *
* Copyright by 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 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. *
* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
#ifndef H5DOpublic_H
#define H5DOpublic_H
#ifdef __cplusplus
extern "C" {
#endif
/**\defgroup H5DO Optimizations
*
* Bypassing default HDF5 behavior in order to optimize for specific
* use cases (H5DO)
*
* HDF5 functions described is this section are implemented in the HDF5 High-level
* library as optimized functions. These functions generally require careful setup
* and testing as they enable an application to bypass portions of the HDF5
* library’s I/O pipeline for performance purposes.
*
* These functions are distributed in the standard HDF5 distribution and are
* available any time the HDF5 High-level library is available.
*
* - \ref H5DOappend
* \n Appends data to a dataset along a specified dimension.
* - \ref H5DOread_chunk
* \n Reads a raw data chunk directly from a dataset in a file into a buffer (DEPRECATED)
* - \ref H5DOwrite_chunk
* \n Writes a raw data chunk from a buffer directly to a dataset in a file (DEPRECATED)
* .
*
*/
/*-------------------------------------------------------------------------
*
* "Optimized dataset" routines.
*
*-------------------------------------------------------------------------
*/
/**
* --------------------------------------------------------------------------
* \ingroup H5DO
*
* \brief Appends data to a dataset along a specified dimension.
*
* \param[in] dset_id Dataset identifier
* \param[in] dxpl_id Dataset transfer property list identifier
* \param[in] axis Dataset Dimension (0-based) for the append
* \param[in] extension Number of elements to append for the
* axis-th dimension
* \param[in] memtype The memory datatype identifier
* \param[in] buf Buffer with data for the append
*
* \return \herr_t
*
* \details The H5DOappend() routine extends a dataset by \p extension
* number of elements along a dimension specified by a
* dimension \p axis and writes \p buf of elements to the
* dataset. Dimension \p axis is 0-based. Elements’ type
* is described by \p memtype.
*
* This routine combines calling H5Dset_extent(),
* H5Sselect_hyperslab(), and H5Dwrite() into a single routine
* that simplifies application development for the common case
* of appending elements to an existing dataset.
*
* For a multi-dimensional dataset, appending to one dimension
* will write a contiguous hyperslab over the other dimensions.
* For example, if a 3-D dataset has dimension sizes (3, 5, 8),
* extending the 0th dimension (currently of size 3) by 3 will
* append 3*5*8 = 120 elements (which must be pointed to by the
* \p buffer parameter) to the dataset, making its final
* dimension sizes (6, 5, 8).
*
* If a dataset has more than one unlimited dimension, any of
* those dimensions may be appended to, although only along
* one dimension per call to H5DOappend().
*
* \since 1.10.0
*
*/
H5_HLDLL herr_t H5DOappend(hid_t dset_id, hid_t dxpl_id, unsigned axis, size_t extension, hid_t memtype,
const void *buf);
/* Symbols defined for compatibility with previous versions of the HDF5 API.
*
* Use of these symbols is deprecated.
*/
#ifndef H5_NO_DEPRECATED_SYMBOLS
/* Compatibility wrappers for functionality moved to H5D */
/**
* --------------------------------------------------------------------------
* \ingroup H5DO
*
* \brief Writes a raw data chunk from a buffer directly to a dataset in a file.
*
* \param[in] dset_id Identifier for the dataset to write to
* \param[in] dxpl_id Transfer property list identifier for
* this I/O operation
* \param[in] filters Mask for identifying the filters in use
* \param[in] offset Logical position of the chunk’s first element
* in the dataspace
* \param[in] data_size Size of the actual data to be written in bytes
* \param[in] buf Buffer containing data to be written to the chunk
*
* \return \herr_t
*
* \deprecated This function was deprecated in favor of the function
* H5Dwrite_chunk() of HDF5-1.10.3.
* The functionality of H5DOwrite_chunk() was moved
* to H5Dwrite_chunk().
* \deprecated For compatibility, this API call has been left as a stub which
* simply calls H5Dwrite_chunk(). New code should use H5Dwrite_chunk().
*
* \details The H5DOwrite_chunk() writes a raw data chunk as specified by its
* logical \p offset in a chunked dataset \p dset_id from the application
* memory buffer \p buf to the dataset in the file. Typically, the data
* in \p buf is preprocessed in memory by a custom transformation, such as
* compression. The chunk will bypass the library’s internal data
* transfer pipeline, including filters, and will be written directly to the file.
*
* \p dxpl_id is a data transfer property list identifier.
*
* \p filters is a mask providing a record of which filters are used
* with the chunk. The default value of the mask is zero (\c 0),
* indicating that all enabled filters are applied. A filter is skipped
* if the bit corresponding to the filter’s position in the pipeline
* (0 ≤ position < 32) is turned on. This mask is saved
* with the chunk in the file.
*
* \p offset is an array specifying the logical position of the first
* element of the chunk in the dataset’s dataspace. The length of the
* offset array must equal the number of dimensions, or rank, of the
* dataspace. The values in \p offset must not exceed the dimension limits
* and must specify a point that falls on a dataset chunk boundary.
*
* \p data_size is the size in bytes of the chunk, representing the number of
* bytes to be read from the buffer \p buf. If the data chunk has been
* precompressed, \p data_size should be the size of the compressed data.
*
* \p buf is the memory buffer containing data to be written to the chunk in the file.
*
* \attention Exercise caution when using H5DOread_chunk() and H5DOwrite_chunk(),
* as they read and write data chunks directly in a file.
* H5DOwrite_chunk() bypasses hyperslab selection, the conversion of data
* from one datatype to another, and the filter pipeline to write the chunk.
* Developers should have experience with these processes before
* using this function. Please see
*
* Using the Direct Chunk Write Function
* for more information.
*
* \note H5DOread_chunk() and H5DOwrite_chunk() are not
* supported under parallel and do not support variable length types.
*
* \par Example
* The following code illustrates the use of H5DOwrite_chunk to write
* an entire dataset, chunk by chunk:
* \snippet H5DO_examples.c H5DOwrite
*
* \version 1.10.3 Function deprecated in favor of H5Dwrite_chunk.
*
* \since 1.8.11
*/
H5_HLDLL herr_t H5DOwrite_chunk(hid_t dset_id, hid_t dxpl_id, uint32_t filters, const hsize_t *offset,
size_t data_size, const void *buf);
/**
* --------------------------------------------------------------------------
* \ingroup H5DO
*
* \brief Reads a raw data chunk directly from a dataset in a file into a buffer.
*
* \param[in] dset_id Identifier for the dataset to be read
* \param[in] dxpl_id Transfer property list identifier for
* this I/O operation
* \param[in] offset Logical position of the chunk’s first
element in the dataspace
* \param[in,out] filters Mask for identifying the filters used
* with the chunk
* \param[in] buf Buffer containing the chunk read from
* the dataset
*
* \return \herr_t
*
* \deprecated This function was deprecated in favor of the function
* H5Dread_chunk() as of HDF5-1.10.3.
* In HDF5 1.10.3, the functionality of H5DOread_chunk()
* was moved to H5Dread_chunk().
* \deprecated For compatibility, this API call has been left as a stub which
* simply calls H5Dread_chunk(). New code should use H5Dread_chunk().
*
* \details The H5DOread_chunk() reads a raw data chunk as specified
* by its logical \p offset in a chunked dataset \p dset_id
* from the dataset in the file into the application memory
* buffer \p buf. The data in \p buf is read directly from the file
* bypassing the library’s internal data transfer pipeline,
* including filters.
*
* \p dxpl_id is a data transfer property list identifier.
*
* The mask \p filters indicates which filters are used with the
* chunk when written. A zero value indicates that all enabled filters
* are applied on the chunk. A filter is skipped if the bit corresponding
* to the filter’s position in the pipeline
* (0 ≤ position < 32) is turned on.
*
* \p offset is an array specifying the logical position of the first
* element of the chunk in the dataset’s dataspace. The length of the
* offset array must equal the number of dimensions, or rank, of the
* dataspace. The values in \p offset must not exceed the dimension
* limits and must specify a point that falls on a dataset chunk boundary.
*
* \p buf is the memory buffer containing the chunk read from the dataset
* in the file.
*
* \par Example
* The following code illustrates the use of H5DOread_chunk()
* to read a chunk from a dataset:
* \snippet H5DO_examples.c H5DOread
*
* \version 1.10.3 Function deprecated in favor of H5Dread_chunk.
*
* \since 1.10.2, 1.8.19
*/
H5_HLDLL herr_t H5DOread_chunk(hid_t dset_id, hid_t dxpl_id, const hsize_t *offset, uint32_t *filters /*out*/,
void *buf /*out*/);
#endif /* H5_NO_DEPRECATED_SYMBOLS */
#ifdef __cplusplus
}
#endif
#endif