dfilter.c

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/*
 * Copyright 2018, University Corporation for Atmospheric Research
 * See netcdf/COPYRIGHT file for copying and redistribution conditions.
 */
 
#include "config.h"
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#ifdef _MSC_VER
#include <io.h>
#endif
 
#include "netcdf.h"
#include "netcdf_filter.h"
#include "ncdispatch.h"
#include "nc4internal.h"
#include "nclog.h"
 
#ifdef USE_HDF5
#include "hdf5internal.h"
#endif
 
#ifdef NETCDF_ENABLE_NCZARR
#include "zdispatch.h"
#endif
 
static void byteswap8(unsigned char*);
static void byteswap4(unsigned char*);
 
/*
Unified filter related code
*/
 
/**************************************************/
/* Per-variable filters */

EXTERNL int
nc_inq_var_filter_ids(int ncid, int varid, size_t* nfiltersp, unsigned int* ids)
{
    NC* ncp;
    int stat = NC_check_id(ncid,&ncp);
    if(stat != NC_NOERR) return stat;
    TRACE(nc_inq_var_filter_ids);
    if((stat = ncp->dispatch->inq_var_filter_ids(ncid,varid,nfiltersp,ids))) goto done;
 
done:
   return stat;
}

EXTERNL int
nc_inq_var_filter_info(int ncid, int varid, unsigned int id, size_t* nparamsp, unsigned int* params)
{
    NC* ncp;
    int stat = NC_check_id(ncid,&ncp);
    if(stat != NC_NOERR) return stat;
    TRACE(nc_inq_var_filter_info);
    if((stat = ncp->dispatch->inq_var_filter_info(ncid,varid,id,nparamsp,params))) goto done;
 
done:
     if(stat == NC_ENOFILTER) nclog(NCLOGWARN,"Undefined filter: %u",(unsigned)id);
     return stat;
}

 
EXTERNL int
nc_def_var_filter(int ncid, int varid, unsigned int id, size_t nparams, const unsigned int* params)
{
    int stat = NC_NOERR;
    NC* ncp;
 
    TRACE(nc_inq_var_filter);
    if((stat = NC_check_id(ncid,&ncp))) return stat;
    if((stat = ncp->dispatch->def_var_filter(ncid,varid,id,nparams,params))) goto done;
done:
     if(stat == NC_ENOFILTER) nclog(NCLOGWARN,"Undefined filter: %u",(unsigned)id);
    return stat;
}

EXTERNL int
nc_inq_var_filter(int ncid, int varid, unsigned int* idp, size_t* nparamsp, unsigned int* params)
{
    NC* ncp;
    size_t nfilters;
    unsigned int* ids = NULL;
    int stat = NC_check_id(ncid,&ncp);
 
    if(stat != NC_NOERR) return stat;
    TRACE(nc_inq_var_filter);
 
    /* Get the number of filters on this variable */
    if((stat = nc_inq_var_filter_ids(ncid,varid,&nfilters, NULL))) goto done;
    /* If no filters, then return zero */
    if(nfilters == 0) {
    if(idp) *idp = 0;
    goto done;
    }
    /* Get the filter ids */
    if((ids = calloc(sizeof(unsigned int),nfilters)) == NULL) {stat = NC_ENOMEM; goto done;}
    if((stat = nc_inq_var_filter_ids(ncid,varid,&nfilters, ids))) goto done;
    /* Get params for the first filter */
    if((stat = nc_inq_var_filter_info(ncid,varid,ids[0],nparamsp,params))) goto done;
    if(idp) *idp = ids[0];
 done:
    nullfree(ids);        
    return stat;
}

 
EXTERNL int
nc_inq_filter_avail(int ncid, unsigned id)
{
    int stat = NC_NOERR;
    NC* ncp;
 
    stat = NC_check_id(ncid,&ncp);
    if(stat != NC_NOERR) return stat;
    if((stat = ncp->dispatch->inq_filter_avail(ncid,id))) goto done;
done:
    return stat;
}
 
/**************************************************/
/* Functions for accessing standardized filters */

int
nc_def_var_bzip2(int ncid, int varid, int level)
{
    int stat = NC_NOERR;
    unsigned ulevel;
    
    if((stat = nc_inq_filter_avail(ncid,H5Z_FILTER_BZIP2))) goto done;
    /* Filter is available */
    /* 1 <= Level <= 9 */
    if (level < 1 || level > 9)
        return NC_EINVAL;
    ulevel = (unsigned) level; /* Keep bit pattern */
    if((stat = nc_def_var_filter(ncid,varid,H5Z_FILTER_BZIP2,1,&ulevel))) goto done;
done:
    return stat;
}

int
nc_inq_var_bzip2(int ncid, int varid, int* hasfilterp, int *levelp)
{
    int stat = NC_NOERR;
    size_t nparams;
    unsigned params = 0;
    int hasfilter = 0;
    
    if((stat = nc_inq_filter_avail(ncid,H5Z_FILTER_BZIP2))) goto done;
    /* Filter is available */
    /* Get filter info */
    stat = nc_inq_var_filter_info(ncid,varid,H5Z_FILTER_BZIP2,&nparams,NULL);
    if(stat == NC_ENOFILTER) {stat = NC_NOERR; hasfilter = 0; goto done;}
    if(stat != NC_NOERR) goto done;
    hasfilter = 1;
    if(nparams != 1) {stat = NC_EFILTER; goto done;}
    if((stat = nc_inq_var_filter_info(ncid,varid,H5Z_FILTER_BZIP2,&nparams,&params))) goto done;
done:
    if(levelp) *levelp = (int)params;
    if(hasfilterp) *hasfilterp = hasfilter;
    return stat;
}

int
nc_def_var_zstandard(int ncid, int varid, int level)
{
#ifdef HAVE_ZSTD
    int stat = NC_NOERR;
    unsigned ulevel;
    
    if((stat = nc_inq_filter_avail(ncid,H5Z_FILTER_ZSTD))) goto done;
    /* Filter is available */
    /* Level must be between -131072 and 22 on Zstandard v. 1.4.5 (~202009)
       Earlier versions have fewer levels (especially fewer negative levels) */
    if (level < -131072 || level > 22)
        return NC_EINVAL;
    ulevel = (unsigned) level; /* Keep bit pattern */
    if((stat = nc_def_var_filter(ncid,varid,H5Z_FILTER_ZSTD,1,&ulevel))) goto done;
done:
    return stat;
#else
    return NC_NOERR;
#endif /*HAVE_ZSTD*/
}

int
nc_inq_var_zstandard(int ncid, int varid, int* hasfilterp, int *levelp)
{
#ifdef HAVE_ZSTD
    int stat = NC_NOERR;
    size_t nparams;
    unsigned params = 0;
    int hasfilter = 0;
    
    if((stat = nc_inq_filter_avail(ncid,H5Z_FILTER_ZSTD))) goto done;
    /* Filter is available */
    /* Get filter info */
    stat = nc_inq_var_filter_info(ncid,varid,H5Z_FILTER_ZSTD,&nparams,NULL);
    if(stat == NC_ENOFILTER) {stat = NC_NOERR; hasfilter = 0; goto done;}
    if(stat != NC_NOERR) goto done;
    hasfilter = 1;
    if(nparams != 1) {stat = NC_EFILTER; goto done;}
    if((stat = nc_inq_var_filter_info(ncid,varid,H5Z_FILTER_ZSTD,&nparams,&params))) goto done;
done:
    if(levelp) *levelp = (int)params;
    if(hasfilterp) *hasfilterp = hasfilter;
    return stat;
#else
    return NC_NOERR;
#endif /*HAVE_ZSTD*/
}

int
nc_def_var_blosc(int ncid, int varid, unsigned subcompressor, unsigned level, unsigned blocksize, unsigned addshuffle)
{
#ifdef HAVE_BLOSC
    int stat = NC_NOERR;
    unsigned params[7];;
    
    if((stat = nc_inq_filter_avail(ncid,H5Z_FILTER_BLOSC))) goto done;
    /* Filter is available */
 
    /* Verify parameters */
    if(addshuffle > (unsigned)BLOSC_BITSHUFFLE) {stat = NC_EINVAL; goto done;}
    if(subcompressor > (unsigned)BLOSC_ZSTD) {stat = NC_EINVAL; goto done;}
 
    /* Set the parameters */
    params[0] = 0;
    params[1] = 0;
    params[2] = 0;
    params[3] = blocksize;
    params[4] = level;
    params[5] = addshuffle;
    params[6] = subcompressor;
    if((stat = nc_def_var_filter(ncid,varid,H5Z_FILTER_BLOSC,7,params))) goto done;
done:
    return stat;
#else
    return NC_NOERR;
#endif
}

int
nc_inq_var_blosc(int ncid, int varid, int* hasfilterp, unsigned* subcompressorp,
         unsigned* levelp, unsigned* blocksizep, unsigned* addshufflep)
{
#ifdef HAVE_BLOSC
    int stat = NC_NOERR;
    size_t nparams;
    unsigned params[7];
    int hasfilter = 0;
    
    if((stat = nc_inq_filter_avail(ncid,H5Z_FILTER_BLOSC))) goto done;
    /* Filter is available */
 
    /* Get filter info */
    stat = nc_inq_var_filter_info(ncid,varid,H5Z_FILTER_BLOSC,&nparams,NULL);
    if(stat == NC_ENOFILTER) {stat = NC_NOERR; hasfilter = 0; goto done;}
    if(stat != NC_NOERR) goto done;
    hasfilter = 1;
    if(nparams != 7) {stat = NC_EFILTER; goto done;}
    if((stat = nc_inq_var_filter_info(ncid,varid,H5Z_FILTER_BLOSC,&nparams,params))) goto done;
    if(blocksizep) *blocksizep = params[3];
    if(levelp) *levelp = params[4];
    if(addshufflep) *addshufflep = params[5];
    if(subcompressorp) *subcompressorp = params[6];
done:
    if(hasfilterp) *hasfilterp = hasfilter;
    return stat;
#else
    return NC_NOERR;
#endif
}