datetime/type.c

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/*
 * Copyright (C) 1995.  Bill Brown <brown@gis.uiuc.edu> & Michael Shapiro
 *
 * This program is free software under the GPL (>=v2)
 * Read the file GPL.TXT coming with GRASS for details.
 */
#include <grass/datetime.h>


int datetime_set_type(DateTime * dt, int mode, int from, int to, int fracsec)
{
    dt->mode = mode;
    dt->from = from;
    dt->to = to;
    dt->fracsec = fracsec;

    dt->year = 0;
    dt->month = 0;
    dt->day = 0;
    dt->hour = 0;
    dt->minute = 0;
    dt->second = 0.0;
    datetime_unset_timezone(dt);

    dt->positive = 1;

    return datetime_check_type(dt);
}

int
datetime_get_type(const DateTime * dt, int *mode, int *from, int *to,
                  int *fracsec)
{
    *mode = dt->mode;
    *to = dt->to;
    *from = dt->from;
    *fracsec = dt->fracsec;
    return datetime_check_type(dt);
}


int datetime_is_valid_type(const DateTime * dt)
{
    /* Returns 0 if DateTime structure is not valid. */
    return datetime_check_type(dt) == 0;
}


int datetime_check_type(const DateTime * dt)
{
    /* Returns 0 for a valid DateTime structure.
       Sets the error code and error message if the structure is not
       valid.  Returns error code. */
    switch (dt->mode) {
    case DATETIME_ABSOLUTE:
    case DATETIME_RELATIVE:
        break;
    default:
        return datetime_error(-1, "invalid datetime 'mode'");
    }

    if (!datetime_is_between(dt->from, DATETIME_YEAR, DATETIME_SECOND))
        return datetime_error(-2, "invalid datetime 'from'");
    if (!datetime_is_between(dt->to, DATETIME_YEAR, DATETIME_SECOND))
        return datetime_error(-3, "invalid datetime 'to'");
    if (dt->from > dt->to)
        return datetime_error(-4, "invalid datetime 'from-to'");
    if (dt->mode == DATETIME_RELATIVE) {
        if (datetime_in_interval_year_month(dt->from)
            && !datetime_in_interval_year_month(dt->to))
            return datetime_error(-5, "invalid relative datetime 'from-to'");
        if (datetime_in_interval_day_second(dt->from)
            && !datetime_in_interval_day_second(dt->to))
            return datetime_error(-5, "invalid relative datetime 'from-to'");
    }
    if (dt->mode == DATETIME_ABSOLUTE && dt->from != DATETIME_YEAR)
        return datetime_error(-6, "invalid absolute datetime 'from'");
    if (dt->to == DATETIME_SECOND && dt->fracsec < 0)
        return datetime_error(-7, "invalid datetime 'fracsec'");

    return 0;
}

int datetime_in_interval_year_month(int x)
{
    return datetime_is_between(x, DATETIME_YEAR, DATETIME_MONTH);
}

int datetime_in_interval_day_second(int x)
{
    return datetime_is_between(x, DATETIME_DAY, DATETIME_SECOND);
}


int datetime_is_absolute(const DateTime * dt)
{
    return (dt->mode == DATETIME_ABSOLUTE);
}


int datetime_is_relative(const DateTime * dt)
{
    return (dt->mode == DATETIME_RELATIVE);
}