/*-------------------------------------------------------------------------
 *
 * nabstime.h--
 *    Definitions for the "new" abstime code.
 *
 *
 * Copyright (c) 1994, Regents of the University of California
 *
 * $Id: nabstime.h,v 1.8 1997/06/23 14:58:51 thomas Exp $
 *
 *-------------------------------------------------------------------------
 */
#ifndef NABSTIME_H
#define NABSTIME_H

#include <time.h>
#include "utils/dt.h"


/* ----------------------------------------------------------------
 *		time types + support macros
 *
 *
 * ----------------------------------------------------------------
 */
typedef int32	AbsoluteTime;
typedef int32	RelativeTime;

typedef struct { 
    int32		status;
    AbsoluteTime	data[2];
} TimeIntervalData;
typedef TimeIntervalData *TimeInterval;

/*
 * Reserved values
 * Epoch is Unix system time zero, but needs to be kept as a reserved
 *  value rather than converting to time since timezone calculations
 *  might move it away from 1970-01-01 00:00:00Z - tgl 97/02/20
 *
 * Pre-v6.1 code had large decimal numbers for reserved values.
 * These were chosen as special 32-bit bit patterns,
 *  so redefine them explicitly using these bit patterns. - tgl 97/02/24
 */
#define EPOCH_ABSTIME	((AbsoluteTime) 0)
#define INVALID_ABSTIME ((AbsoluteTime) 0x4FFFFFFE) /* 2147483647 == 2^31 - 1 */
#define CURRENT_ABSTIME ((AbsoluteTime) 0x4FFFFFFD) /* 2147483646 == 2^31 - 2 */
#define NOEND_ABSTIME	((AbsoluteTime) 0x4FFFFFFC) /* 2147483645 == 2^31 - 3 */
#define BIG_ABSTIME	((AbsoluteTime) 0x4FFFFFFB) /* 2147483644 == 2^31 - 4 */

#if defined(aix)
/*
 * AIX considers 2147483648 == -2147483648 (since they have the same bit
 * representation) but uses a different sign sense in a comparison to 
 * these integer constants depending on whether the constant is signed 
 * or not!
 */
/*#define NOSTART_ABSTIME	((AbsoluteTime) HIBITI)	*/	/* - 2^31 */
#define NOSTART_ABSTIME      ((AbsoluteTime) INT_MIN)
#else
/*#define NOSTART_ABSTIME ((AbsoluteTime) 2147483648)*/	/* - 2^31 */
#define NOSTART_ABSTIME ((AbsoluteTime) 0x80000001) /* -2147483647 == - 2^31 */
#endif /* aix */

#define INVALID_RELTIME ((RelativeTime) 0x4FFFFFFE) /* 2147483647 == 2^31 - 1 */

#define AbsoluteTimeIsValid(time) \
    ((bool) ((time) != INVALID_ABSTIME))

#define AbsoluteTimeIsReal(time) \
    ((bool) (((AbsoluteTime) time) < NOEND_ABSTIME && \
	     ((AbsoluteTime) time) > NOSTART_ABSTIME))

/* have to include this because EPOCH_ABSTIME used to be invalid - yuk */
#define AbsoluteTimeIsBackwardCompatiblyValid(time) \
    ((bool) (((AbsoluteTime) time) != INVALID_ABSTIME && \
	     ((AbsoluteTime) time) > EPOCH_ABSTIME))

#define AbsoluteTimeIsBackwardCompatiblyReal(time) \
    ((bool) (((AbsoluteTime) time) < NOEND_ABSTIME && \
	     ((AbsoluteTime) time) > NOSTART_ABSTIME && \
             ((AbsoluteTime) time) > EPOCH_ABSTIME))

#define RelativeTimeIsValid(time) \
    ((bool) (((RelativeTime) time) != INVALID_RELTIME))

extern AbsoluteTime GetCurrentAbsoluteTime(void);

/*
 * getSystemTime --
 *	Returns system time.
 */
#define getSystemTime() \
    ((time_t) (time(0l)))


/*
 * nabstime.c prototypes 
 */
extern AbsoluteTime nabstimein(char *timestr);
extern char *nabstimeout(AbsoluteTime time);

extern bool abstimeeq(AbsoluteTime t1, AbsoluteTime t2);
extern bool abstimene(AbsoluteTime t1, AbsoluteTime t2);
extern bool abstimelt(AbsoluteTime t1, AbsoluteTime t2);
extern bool abstimegt(AbsoluteTime t1, AbsoluteTime t2);
extern bool abstimele(AbsoluteTime t1, AbsoluteTime t2);
extern bool abstimege(AbsoluteTime t1, AbsoluteTime t2);
extern bool abstime_finite(AbsoluteTime time);

extern AbsoluteTime datetime_abstime(DateTime *datetime);
extern DateTime *abstime_datetime(AbsoluteTime abstime);

extern bool AbsoluteTimeIsBefore(AbsoluteTime time1, AbsoluteTime time2);
extern bool AbsoluteTimeIsAfter(AbsoluteTime time1, AbsoluteTime time2);

extern AbsoluteTime tm2abstime(struct tm *tm, int tz);
extern void abstime2tm(AbsoluteTime time, int *tzp, struct tm *tm, char *tzn);

#endif /* NABSTIME_H */
