freebsd-src/usr.sbin/xntpd/include/ntp_unixtime.h
1994-09-29 23:04:24 +00:00

120 lines
3.1 KiB
C

/*
* ntp_unixtime.h - contains constants and macros for converting between
* NTP time stamps (l_fp) and Unix times (struct timeval)
*/
#include "ntp_types.h"
#include <sys/time.h>
/* gettimeofday() takes two args in BSD and only one in SYSV */
#ifdef SYSV_TIMEOFDAY
# define GETTIMEOFDAY(a, b) (gettimeofday(a))
# define SETTIMEOFDAY(a, b) (settimeofday(a))
#else /* ! SYSV_TIMEOFDAY */
# define GETTIMEOFDAY(a, b) (gettimeofday(a, b))
# define SETTIMEOFDAY(a, b) (settimeofday(a, b))
#endif /* SYSV_TIMEOFDAY */
/*
* Time of day conversion constant. Ntp's time scale starts in 1900,
* Unix in 1970.
*/
#define JAN_1970 0x83aa7e80 /* 2208988800 1970 - 1900 in seconds */
/*
* These constants are used to round the time stamps computed from
* a struct timeval to the microsecond (more or less). This keeps
* things neat.
*/
#define TS_MASK 0xfffff000 /* mask to usec, for time stamps */
#define TS_ROUNDBIT 0x00000800 /* round at this bit */
/*
* Convert usec to a time stamp fraction. If you use this the program
* must include the following declarations:
*/
extern u_long ustotslo[];
extern u_long ustotsmid[];
extern u_long ustotshi[];
#define TVUTOTSF(tvu, tsf) \
(tsf) = ustotslo[(tvu) & 0xff] \
+ ustotsmid[((tvu) >> 8) & 0xff] \
+ ustotshi[((tvu) >> 16) & 0xf]
/*
* Convert a struct timeval to a time stamp.
*/
#define TVTOTS(tv, ts) \
do { \
(ts)->l_ui = (u_long)(tv)->tv_sec; \
TVUTOTSF((tv)->tv_usec, (ts)->l_uf); \
} while(0)
#define sTVTOTS(tv, ts) \
do { \
int isneg = 0; \
long usec; \
(ts)->l_ui = (tv)->tv_sec; \
usec = (tv)->tv_usec; \
if (((tv)->tv_sec < 0) || ((tv)->tv_usec < 0)) { \
usec = -usec; \
(ts)->l_ui = -(ts)->l_ui; \
isneg = 1; \
} \
TVUTOTSF(usec, (ts)->l_uf); \
if (isneg) { \
L_NEG((ts)); \
} \
} while(0)
/*
* TV_SHIFT is used to turn the table result into a usec value. To round,
* add in TV_ROUNDBIT before shifting
*/
#define TV_SHIFT 3
#define TV_ROUNDBIT 0x4
/*
* Convert a time stamp fraction to microseconds. The time stamp
* fraction is assumed to be unsigned. To use this in a program, declare:
*/
extern long tstouslo[];
extern long tstousmid[];
extern long tstoushi[];
#define TSFTOTVU(tsf, tvu) \
(tvu) = (tstoushi[((tsf) >> 24) & 0xff] \
+ tstousmid[((tsf) >> 16) & 0xff] \
+ tstouslo[((tsf) >> 9) & 0x7f] \
+ TV_ROUNDBIT) >> TV_SHIFT
/*
* Convert a time stamp to a struct timeval. The time stamp
* has to be positive.
*/
#define TSTOTV(ts, tv) \
do { \
(tv)->tv_sec = (ts)->l_ui; \
TSFTOTVU((ts)->l_uf, (tv)->tv_usec); \
if ((tv)->tv_usec == 1000000) { \
(tv)->tv_sec++; \
(tv)->tv_usec = 0; \
} \
} while (0)
/*
* Convert milliseconds to a time stamp fraction. This shouldn't be
* here, but it is convenient since the guys who use the definition will
* often be including this file anyway.
*/
extern u_long msutotsflo[];
extern u_long msutotsfhi[];
#define MSUTOTSF(msu, tsf) \
(tsf) = msutotsfhi[((msu) >> 5) & 0x1f] + msutotsflo[(msu) & 0x1f]
extern char * tvtoa P((const struct timeval *));
extern char * utvtoa P((const struct timeval *));