netcdf-c/libhdf4/hdf4dispatch.c
Dennis Heimbigner aeb3ac2809 Mostly revert the filter code to reduce its complexity of use.
re: https://github.com/Unidata/netcdf-c/issues/1836

Revert the internal filter code to simplify it. From the user's
point of view, the only visible changes should be:

1. The functions that convert text to filter specs have had their signature reverted and have been moved to netcdf_aux.h
2. Some filter API functions now return NC_ENOFILTER when inquiry is made about some filter.

Internally,the dispatch table has been modified to get rid of the filter_actions
entry and associated complex structures. It has been replaced with
inq_var_filter_ids and inq_var_filter_info entries and the dispatch table
version has been bumped to 3. Corresponding NOOP and NOTNC4 functions
were added to libdispatch/dnotnc4.c. Also, the filter_action entries
in dispatch tables were replaced for all dispatch code bases (HDF5, DAP2,
etc). This should only impact UDF users.

In the process, it became clear that the form of the filters
field in NC_VAR_INFO_T was format dependent, so I converted it to
be of type void* and pushed its management into the various dispatch
code bases. Specifically libhdf5 and libnczarr now manage the filters
field in their own way.

The auxilliary functions for parsing textual filter specifications
were moved to netcdf_aux.h and were renamed to the following:
* ncaux_h5filterspec_parse
* ncaux_h5filterspec_parselist
* ncaux_h5filterspec_free
* ncaux_h5filter_fix8

Misc. Other Changes:

1. Document NUG/filters.md updated to reflect the changes above.
2. All the old data types (structs and enums)
   used by filter_actions actions were deleted.
   The exception is the NC_H5_Filterspec because it is needed
   by ncaux_h5filterspec_parselist.
3. Clientside filters were removed -- another enhancement
   for which no-one ever asked.
4. The ability to remove filters was itself removed.
5. Some functionality needed by nczarr was moved from libhdf5
   to libsrc4 e.g. nc4_find_default_chunksizes
6. All the filterx code was removed
7. ncfilter.h and nc4filter.c no longer used

Misc. Unrelated Changes:

1. The nczarr_test makefile clean was leaving some directories; so
   add clean-local to take care of them.
2020-09-27 12:43:46 -06:00

137 lines
2.7 KiB
C

/* Copyright 2018, UCAR/Unidata See netcdf/COPYRIGHT file for copying
* and redistribution conditions.*/
/**
* @file
* @internal Dispatch code for HDF4. HDF4 access is read-only, for
* HDF4 SD files only.
*
* @author Ed Hartnett
*/
#include "config.h"
#include <stdlib.h>
#include "hdf4dispatch.h"
#include "nc4dispatch.h"
#include "hdf5dispatch.h"
/* This is the dispatch object that holds pointers to all the
* functions that make up the HDF4 dispatch interface. */
static const NC_Dispatch HDF4_dispatcher = {
NC_FORMATX_NC_HDF4,
NC_DISPATCH_VERSION,
NC_RO_create,
NC_HDF4_open,
NC_RO_redef,
NC_RO__enddef,
NC_RO_sync,
NC_HDF4_abort,
NC_HDF4_close,
NC_RO_set_fill,
NC_HDF4_inq_format,
NC_HDF4_inq_format_extended,
NC4_inq,
NC4_inq_type,
NC_RO_def_dim,
NC4_inq_dimid,
HDF5_inq_dim,
NC4_inq_unlimdim,
NC_RO_rename_dim,
NC4_inq_att,
NC4_inq_attid,
NC4_inq_attname,
NC_RO_rename_att,
NC_RO_del_att,
NC4_get_att,
NC_RO_put_att,
NC_RO_def_var,
NC4_inq_varid,
NC_RO_rename_var,
NC_HDF4_get_vara,
NC_RO_put_vara,
NCDEFAULT_get_vars,
NCDEFAULT_put_vars,
NCDEFAULT_get_varm,
NCDEFAULT_put_varm,
NC4_inq_var_all,
NC_NOTNC4_var_par_access,
NC_RO_def_var_fill,
NC4_show_metadata,
NC4_inq_unlimdims,
NC4_inq_ncid,
NC4_inq_grps,
NC4_inq_grpname,
NC4_inq_grpname_full,
NC4_inq_grp_parent,
NC4_inq_grp_full_ncid,
NC4_inq_varids,
NC4_inq_dimids,
NC4_inq_typeids,
NC4_inq_type_equal,
NC_NOTNC4_def_grp,
NC_NOTNC4_rename_grp,
NC4_inq_user_type,
NC4_inq_typeid,
NC_NOTNC4_def_compound,
NC_NOTNC4_insert_compound,
NC_NOTNC4_insert_array_compound,
NC_NOTNC4_inq_compound_field,
NC_NOTNC4_inq_compound_fieldindex,
NC_NOTNC4_def_vlen,
NC_NOTNC4_put_vlen_element,
NC_NOTNC4_get_vlen_element,
NC_NOTNC4_def_enum,
NC_NOTNC4_insert_enum,
NC_NOTNC4_inq_enum_member,
NC_NOTNC4_inq_enum_ident,
NC_NOTNC4_def_opaque,
NC_NOTNC4_def_var_deflate,
NC_NOTNC4_def_var_fletcher32,
NC_NOTNC4_def_var_chunking,
NC_NOTNC4_def_var_endian,
NC_NOTNC4_def_var_filter,
NC_NOTNC4_set_var_chunk_cache,
NC_NOTNC4_get_var_chunk_cache,
NC_NOOP_inq_var_filter_ids,
NC_NOOP_inq_var_filter_info,
};
const NC_Dispatch *HDF4_dispatch_table = NULL;
/**
* @internal Initialize HDF4 dispatch layer.
*
* @return ::NC_NOERR No error.
* @author Ed Hartnett
*/
int
NC_HDF4_initialize(void)
{
HDF4_dispatch_table = &HDF4_dispatcher;
return NC_NOERR;
}
/**
* @internal Finalize HDF4 dispatch layer.
*
* @return ::NC_NOERR No error.
* @author Ed Hartnett
*/
int
NC_HDF4_finalize(void)
{
return NC_NOERR;
}