eccodes/src/grib_accessor_class_scale.c

/*
 * (C) Copyright 2005- ECMWF.
 *
 * This software is licensed under the terms of the Apache Licence Version 2.0
 * which can be obtained at http://www.apache.org/licenses/LICENSE-2.0.
 *
 * In applying this licence, ECMWF does not waive the privileges and immunities granted to it by
 * virtue of its status as an intergovernmental organisation nor does it submit to any jurisdiction.
 */

/**************************************
 *  Enrico Fucile
 **************************************/


#include "grib_api_internal.h"
/*
   This is used by make_class.pl

   START_CLASS_DEF
   CLASS      = accessor
   SUPER      = grib_accessor_class_double
   IMPLEMENTS = unpack_double;pack_double;is_missing
   IMPLEMENTS = pack_long
   IMPLEMENTS = init
   MEMBERS=const char*    value
   MEMBERS=const char*    multiplier
   MEMBERS=const char*    divisor
   MEMBERS=const char*    truncating
   END_CLASS_DEF

 */

/* START_CLASS_IMP */

/*

Don't edit anything between START_CLASS_IMP and END_CLASS_IMP
Instead edit values between START_CLASS_DEF and END_CLASS_DEF
or edit "accessor.class" and rerun ./make_class.pl

*/

static int is_missing(grib_accessor*);
static int pack_double(grib_accessor*, const double* val, size_t* len);
static int pack_long(grib_accessor*, const long* val, size_t* len);
static int unpack_double(grib_accessor*, double* val, size_t* len);
static void init(grib_accessor*, const long, grib_arguments*);
static void init_class(grib_accessor_class*);

typedef struct grib_accessor_scale
{
    grib_accessor att;
    /* Members defined in gen */
    /* Members defined in double */
    /* Members defined in scale */
    const char* value;
    const char* multiplier;
    const char* divisor;
    const char* truncating;
} grib_accessor_scale;

extern grib_accessor_class* grib_accessor_class_double;

static grib_accessor_class _grib_accessor_class_scale = {
    &grib_accessor_class_double, /* super                     */
    "scale",                     /* name                      */
    sizeof(grib_accessor_scale), /* size                      */
    0,                           /* inited */
    &init_class,                 /* init_class */
    &init,                       /* init                      */
    0,                           /* post_init                      */
    0,                           /* free mem                       */
    0,                           /* describes himself         */
    0,                           /* get length of section     */
    0,                           /* get length of string      */
    0,                           /* get number of values      */
    0,                           /* get number of bytes      */
    0,                           /* get offset to bytes           */
    0,                           /* get native type               */
    0,                           /* get sub_section                */
    0,                           /* grib_pack procedures long      */
    &is_missing,                 /* grib_pack procedures long      */
    &pack_long,                  /* grib_pack procedures long      */
    0,                           /* grib_unpack procedures long    */
    &pack_double,                /* grib_pack procedures double    */
    &unpack_double,              /* grib_unpack procedures double  */
    0,                           /* grib_pack procedures string    */
    0,                           /* grib_unpack procedures string  */
    0,                           /* grib_pack array procedures string    */
    0,                           /* grib_unpack array procedures string  */
    0,                           /* grib_pack procedures bytes     */
    0,                           /* grib_unpack procedures bytes   */
    0,                           /* pack_expression */
    0,                           /* notify_change   */
    0,                           /* update_size   */
    0,                           /* preferred_size   */
    0,                           /* resize   */
    0,                           /* nearest_smaller_value */
    0,                           /* next accessor    */
    0,                           /* compare vs. another accessor   */
    0,                           /* unpack only ith value          */
    0,                           /* unpack a subarray         */
    0,                           /* clear          */
    0,                           /* clone accessor          */
};


grib_accessor_class* grib_accessor_class_scale = &_grib_accessor_class_scale;


static void init_class(grib_accessor_class* c)
{
    c->dump                   = (*(c->super))->dump;
    c->next_offset            = (*(c->super))->next_offset;
    c->string_length          = (*(c->super))->string_length;
    c->value_count            = (*(c->super))->value_count;
    c->byte_count             = (*(c->super))->byte_count;
    c->byte_offset            = (*(c->super))->byte_offset;
    c->get_native_type        = (*(c->super))->get_native_type;
    c->sub_section            = (*(c->super))->sub_section;
    c->pack_missing           = (*(c->super))->pack_missing;
    c->unpack_long            = (*(c->super))->unpack_long;
    c->pack_string            = (*(c->super))->pack_string;
    c->unpack_string          = (*(c->super))->unpack_string;
    c->pack_string_array      = (*(c->super))->pack_string_array;
    c->unpack_string_array    = (*(c->super))->unpack_string_array;
    c->pack_bytes             = (*(c->super))->pack_bytes;
    c->unpack_bytes           = (*(c->super))->unpack_bytes;
    c->pack_expression        = (*(c->super))->pack_expression;
    c->notify_change          = (*(c->super))->notify_change;
    c->update_size            = (*(c->super))->update_size;
    c->preferred_size         = (*(c->super))->preferred_size;
    c->resize                 = (*(c->super))->resize;
    c->nearest_smaller_value  = (*(c->super))->nearest_smaller_value;
    c->next                   = (*(c->super))->next;
    c->compare                = (*(c->super))->compare;
    c->unpack_double_element  = (*(c->super))->unpack_double_element;
    c->unpack_double_subarray = (*(c->super))->unpack_double_subarray;
    c->clear                  = (*(c->super))->clear;
    c->make_clone             = (*(c->super))->make_clone;
}

/* END_CLASS_IMP */

static void init(grib_accessor* a, const long l, grib_arguments* c)
{
    grib_accessor_scale* self = (grib_accessor_scale*)a;
    int n                     = 0;

    self->value      = grib_arguments_get_name(grib_handle_of_accessor(a), c, n++);
    self->multiplier = grib_arguments_get_name(grib_handle_of_accessor(a), c, n++);
    self->divisor    = grib_arguments_get_name(grib_handle_of_accessor(a), c, n++);
    self->truncating = grib_arguments_get_name(grib_handle_of_accessor(a), c, n++);
}

static int unpack_double(grib_accessor* a, double* val, size_t* len)
{
    grib_accessor_scale* self = (grib_accessor_scale*)a;
    int ret                   = 0;
    long value                = 0;
    long multiplier           = 0;
    long divisor              = 0;

    if (*len < 1) {
        ret = GRIB_ARRAY_TOO_SMALL;
        grib_context_log(a->context, GRIB_LOG_ERROR,
                         "Accessor %s cannot gather value for %s and/or %s error %d",
                         a->name, self->multiplier, self->divisor, ret);
        return ret;
    }

    if ((ret = grib_get_long_internal(grib_handle_of_accessor(a), self->divisor, &divisor)) != GRIB_SUCCESS)
        return ret;

    if ((ret = grib_get_long_internal(grib_handle_of_accessor(a), self->multiplier, &multiplier)) != GRIB_SUCCESS)
        return ret;

    if ((ret = grib_get_long_internal(grib_handle_of_accessor(a), self->value, &value)) != GRIB_SUCCESS)
        return ret;

    if (value == GRIB_MISSING_LONG)
        *val = GRIB_MISSING_DOUBLE;
    else
        *val = ((double)(value * multiplier)) / divisor;
    /*printf("unpack_double: divisor=%ld multiplier=%ld long_value=%ld scaled_value=%.30f\n",(double)divisor,(double)multiplier,value,*val);*/

    if (ret == GRIB_SUCCESS)
        *len = 1;

    return ret;
}

static int pack_long(grib_accessor* a, const long* val, size_t* len)
{
    const double dval = (double)*val;
    return pack_double(a, &dval, len);
}

static int pack_double(grib_accessor* a, const double* val, size_t* len)
{
    grib_accessor_scale* self = (grib_accessor_scale*)a;
    int ret                   = 0;

    long value      = 0;
    long divisor    = 0;
    long multiplier = 0;
    long truncating = 0;
    double x;

    ret = grib_get_long_internal(grib_handle_of_accessor(a), self->divisor, &divisor);
    if (ret != GRIB_SUCCESS) {
        grib_context_log(a->context, GRIB_LOG_ERROR, "Accessor %s cannot gather value for %s error %d \n", a->name, self->divisor, ret);
        return ret;
    }
    ret = grib_get_long_internal(grib_handle_of_accessor(a), self->multiplier, &multiplier);
    if (ret != GRIB_SUCCESS) {
        grib_context_log(a->context, GRIB_LOG_ERROR, "Accessor %s cannot gather value for %s error %d \n", a->name, self->divisor, ret);
        return ret;
    }
    if (self->truncating) {
        ret = grib_get_long_internal(grib_handle_of_accessor(a), self->truncating, &truncating);
        if (ret != GRIB_SUCCESS) {
            grib_context_log(a->context, GRIB_LOG_ERROR, "Accessor %s cannot gather value for %s error %d \n", a->name, self->truncating, ret);
            return ret;
        }
    }

    if (multiplier == 0) {
        grib_context_log(a->context, GRIB_LOG_ERROR, "Accessor %s cannot divide by a zero multiplier %s error %d  \n", a->name, self->multiplier, ret);
        return GRIB_ENCODING_ERROR;
    }

    x = *val * (double)divisor / (double)multiplier;
    if (*val == GRIB_MISSING_DOUBLE)
        value = GRIB_MISSING_LONG;
    else if (truncating) {
        value = (long)x;
    }
    else {
        value = x > 0 ? (long)(x + 0.5) : (long)(x - 0.5);
    }

    ret = grib_set_long_internal(grib_handle_of_accessor(a), self->value, value);
    if (ret)
        grib_context_log(a->context, GRIB_LOG_ERROR, "Accessor %s cannot pack value for %s error %d \n", a->name, self->value, ret);

    if (ret == GRIB_SUCCESS)
        *len = 1;

    return ret;
}

static int is_missing(grib_accessor* a)
{
    grib_accessor_scale* self = (grib_accessor_scale*)a;
    grib_accessor* av         = grib_find_accessor(grib_handle_of_accessor(a), self->value);

    if (!av)
        return GRIB_NOT_FOUND;
    return grib_is_missing_internal(av);
#if 0
    int ret=0;
    long value=0;

    if((ret = grib_get_long_internal(grib_handle_of_accessor(a),self->value, &value))!= GRIB_SUCCESS){
        grib_context_log(a->context, GRIB_LOG_ERROR,
        "Accessor %s cannot gather value for %s error %d \n", a->name,
        self->value, ret);
        return 0;
    }

    return (value == GRIB_MISSING_LONG);
#endif
}