/*=============================================================================
* drt/sys/ktz.c
*	DRT primitive timezone functions for the 'struct drt_tz' type.
*
* History
*	0.01, 1999-08-12, David R Tribble.
*	First cut.
*
* Copyright ©1999, by David R. Tribble, all rights reserved.
* See "drt/sys/copyr.txt" for more information.
*----------------------------------------------------------------------------*/


/* Identification */

static const char	id[] =
    "@(#)drt/sys/ktz.c 0.01";


/* System includes */

#include <assert.h>
#define drt_std_assert_h	1

#if TEST || DEBUG
 #include <stdio.h>
 #define drt_std_stdio_h	1
#endif


/* Special includes */

#include "kdefs.h"


/* Local includes */

#include "kdebug.h"

#include "ktime.h"
#include "ktimec.h"


/* Local macros */

#if TEST
 #if DEBUG
  #define T(e)		(e)
 #else
  #define T(e)		(0)
 #endif
#else
 #define T(e)		(0)
#endif


/*-----------------------------------------------------------------------------
* Public constants
*----------------------------------------------------------------------------*/

#if DRT_TZ_VS/100 != 1
#error DRT_TZ_VS has changed
#endif

const int		drt_tz_VS = DRT_TZ_VS;
					/* Struct version number	*/


/*-----------------------------------------------------------------------------
* Public functions
*----------------------------------------------------------------------------*/

/*-----------------------------------------------------------------------------
* drt_tz_validate()
*	Verifies that 'th' is a valid date object.
*
* Returns
*	True if 'th' is a valid object, otherwise false.
*----------------------------------------------------------------------------*/

bool drt_tz_validate(const struct drt_tz *th)
{
#if DRT_TZ_VS != 101
#error DRT_TZ_VS has changed
#endif

    /* Verify the object */
    if (th == null)
        return (false);

    if (th->tz_vers/100 != DRT_TZ_VS/100)
        return (false);

    /* Object appears to be valid */
    return (true);
}


/*-----------------------------------------------------------------------------
* drt_tz_zero()
*	Initializes date object 'th', setting its members to reflect the zero
*	(Zulu, UT) timezone.
*
* Returns
*	True if pointer 'th' is not null, otherwise false.
*----------------------------------------------------------------------------*/

bool drt_tz_zero(struct drt_tz *th)
{
#if DRT_TZ_VS != 101
#error DRT_TZ_VS has changed
#endif

#if DEBUG >= 2
    DrtTrace	dbg("drt_tz_zero");
#endif

    /* Initialize the date members to Zulu timezone */
    th->tz_vers =    DRT_TZ_VS;
    th->tz_hour =    0;
    th->tz_min =     0;
    th->tz_sec =     0;
    th->tz_dst =     false;
    th->tz_name[0] = 'Z';
    th->tz_name[1] = '\0';

    return (true);
}


/* End ktz.c */