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3ffe7be446
re: Discussion https://github.com/Unidata/netcdf-c/discussions/2214 The primary change is to support so-called "standard filters". A standard filter is one that is defined by the following netcdf-c API: ```` int nc_def_var_XXX(int ncid, int varid, size_t nparams, unsigned* params); int nc_inq_var_XXXX(int ncid, int varid, int* usefilterp, unsigned* params); ```` So for example, zstandard would be a standard filter by defining the functions *nc_def_var_zstandard* and *nc_inq_var_zstandard*. In order to define these functions, we need a new dispatch function: ```` int nc_inq_filter_avail(int ncid, unsigned filterid); ```` This function, combined with the existing filter API can be used to implement arbitrary standard filters using a simple code pattern. Note that I would have preferred that this function return a list of all available filters, but HDF5 does not support that functionality. So this PR implements the dispatch function and implements the following standard functions: + bzip2 + zstandard + blosc Specific test cases are also provided for HDF5 and NCZarr. Over time, other specific standard filters will be defined. ## Primary Changes * Add nc_inq_filter_avail() to netcdf-c API. * Add standard filter implementations to test use of *nc_inq_filter_avail*. * Bump the dispatch table version number and add to all the relevant dispatch tables (libsrc, libsrcp, etc). * Create a program to invoke nc_inq_filter_avail so that it is accessible to shell scripts. * Cleanup szip support to properly support szip when HDF5 is disabled. This involves detecting libsz separately from testing if HDF5 supports szip. * Integrate shuffle and fletcher32 into the existing filter API. This means that, for example, nc_def_var_fletcher32 is now a wrapper around nc_def_var_filter. * Extend the Codec defaulting to allow multiple default shared libraries. ## Misc. Changes * Modify configure.ac/CMakeLists.txt to look for the relevant libraries implementing standard filters. * Modify libnetcdf.settings to list available standard filters (including deflate and szip). * Add CMake test modules to locate libbz2 and libzstd. * Cleanup the HDF5 memory manager function use in the plugins. * remove unused file include//ncfilter.h * remove tests for the HDF5 memory operations e.g. H5allocate_memory. * Add flag to ncdump to force use of _Filter instead of _Deflate or _Shuffle or _Fletcher32. Used for testing.
143 lines
2.8 KiB
C
143 lines
2.8 KiB
C
/* Copyright 2018, UCAR/Unidata See netcdf/COPYRIGHT file for copying
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* and redistribution conditions.*/
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/**
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* @file
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* @internal Dispatch code for HDF4. HDF4 access is read-only, for
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* HDF4 SD files only.
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*
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* @author Ed Hartnett
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*/
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#include "config.h"
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#include <stdlib.h>
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#include "hdf4dispatch.h"
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#include "nc4dispatch.h"
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#include "hdf5dispatch.h"
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#include "netcdf_filter.h"
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/* This is the dispatch object that holds pointers to all the
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* functions that make up the HDF4 dispatch interface. */
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static const NC_Dispatch HDF4_dispatcher = {
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NC_FORMATX_NC_HDF4,
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NC_DISPATCH_VERSION,
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NC_RO_create,
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NC_HDF4_open,
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NC_RO_redef,
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NC_RO__enddef,
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NC_RO_sync,
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NC_HDF4_abort,
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NC_HDF4_close,
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NC_RO_set_fill,
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NC_HDF4_inq_format,
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NC_HDF4_inq_format_extended,
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NC4_inq,
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NC4_inq_type,
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NC_RO_def_dim,
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NC4_inq_dimid,
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HDF5_inq_dim,
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NC4_inq_unlimdim,
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NC_RO_rename_dim,
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NC4_inq_att,
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NC4_inq_attid,
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NC4_inq_attname,
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NC_RO_rename_att,
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NC_RO_del_att,
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NC4_get_att,
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NC_RO_put_att,
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NC_RO_def_var,
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NC4_inq_varid,
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NC_RO_rename_var,
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NC_HDF4_get_vara,
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NC_RO_put_vara,
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NCDEFAULT_get_vars,
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NCDEFAULT_put_vars,
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NCDEFAULT_get_varm,
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NCDEFAULT_put_varm,
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NC4_inq_var_all,
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NC_NOTNC4_var_par_access,
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NC_RO_def_var_fill,
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NC4_show_metadata,
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NC4_inq_unlimdims,
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NC4_inq_ncid,
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NC4_inq_grps,
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NC4_inq_grpname,
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NC4_inq_grpname_full,
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NC4_inq_grp_parent,
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NC4_inq_grp_full_ncid,
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NC4_inq_varids,
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NC4_inq_dimids,
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NC4_inq_typeids,
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NC4_inq_type_equal,
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NC_NOTNC4_def_grp,
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NC_NOTNC4_rename_grp,
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NC4_inq_user_type,
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NC4_inq_typeid,
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NC_NOTNC4_def_compound,
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NC_NOTNC4_insert_compound,
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NC_NOTNC4_insert_array_compound,
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NC_NOTNC4_inq_compound_field,
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NC_NOTNC4_inq_compound_fieldindex,
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NC_NOTNC4_def_vlen,
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NC_NOTNC4_put_vlen_element,
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NC_NOTNC4_get_vlen_element,
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NC_NOTNC4_def_enum,
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NC_NOTNC4_insert_enum,
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NC_NOTNC4_inq_enum_member,
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NC_NOTNC4_inq_enum_ident,
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NC_NOTNC4_def_opaque,
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NC_NOTNC4_def_var_deflate,
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NC_NOTNC4_def_var_fletcher32,
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NC_NOTNC4_def_var_chunking,
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NC_NOTNC4_def_var_endian,
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NC_NOTNC4_def_var_filter,
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NC_NOTNC4_set_var_chunk_cache,
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NC_NOTNC4_get_var_chunk_cache,
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NC_NOOP_inq_var_filter_ids,
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NC_NOOP_inq_var_filter_info,
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NC_NOTNC4_def_var_quantize,
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NC_NOTNC4_inq_var_quantize,
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NC_NOOP_inq_filter_avail,
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};
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const NC_Dispatch *HDF4_dispatch_table = NULL;
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/**
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* @internal Initialize HDF4 dispatch layer.
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*
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* @return ::NC_NOERR No error.
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* @author Ed Hartnett
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*/
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int
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NC_HDF4_initialize(void)
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{
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HDF4_dispatch_table = &HDF4_dispatcher;
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return NC_NOERR;
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}
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/**
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* @internal Finalize HDF4 dispatch layer.
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*
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* @return ::NC_NOERR No error.
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* @author Ed Hartnett
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*/
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int
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NC_HDF4_finalize(void)
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{
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return NC_NOERR;
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}
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