diff options
Diffstat (limited to 'usr.sbin/xntpd/include/ntp_timex.h')
| -rw-r--r-- | usr.sbin/xntpd/include/ntp_timex.h | 158 |
1 files changed, 158 insertions, 0 deletions
diff --git a/usr.sbin/xntpd/include/ntp_timex.h b/usr.sbin/xntpd/include/ntp_timex.h new file mode 100644 index 0000000..1756e2e --- /dev/null +++ b/usr.sbin/xntpd/include/ntp_timex.h @@ -0,0 +1,158 @@ +/****************************************************************************** + * * + * Copyright (c) David L. Mills 1993 * + * * + * Permission to use, copy, modify, and distribute this software and its * + * documentation for any purpose and without fee is hereby granted, provided * + * that the above copyright notice appears in all copies and that both the * + * copyright notice and this permission notice appear in supporting * + * documentation, and that the name University of Delaware not be used in * + * advertising or publicity pertaining to distribution of the software * + * without specific, written prior permission. The University of Delaware * + * makes no representations about the suitability this software for any * + * purpose. It is provided "as is" without express or implied warranty. * + * * + ******************************************************************************/ + +/* + * Modification history timex.h + * + * 28 Nov 93 David L. Mills + * Adjusted parameters to improve stability and increase poll interval + * + * 10 Oct 93 Torsten Duwe + * Changed to ntp_timex.h (#ifdef'd HAVE_SYS_TIMEX_H) + * + * 17 Sep 93 David L. Mills + * Created file + */ +/* + * This header file defines the Network Time Protocol (NTP) interfaces + * for user and daemon application programs. These are implemented using + * private syscalls and data structures and require specific kernel + * support. + * + * NAME + * ntp_gettime - NTP user application interface + * + * SYNOPSIS + * #include <sys/timex.h> + * + * int syscall(SYS_ntp_gettime, tptr) + * + * int SYS_ntp_gettime defined in syscall.h header file + * struct ntptimeval *tptr pointer to ntptimeval structure + * + * NAME + * ntp_adjtime - NTP daemon application interface + * + * SYNOPSIS + * #include <sys/timex.h> + * + * int syscall(SYS_ntp_adjtime, mode, tptr) + * + * int SYS_ntp_adjtime defined in syscall.h header file + * struct timex *tptr pointer to timex structure + * + */ +#ifndef _NTP_TIMEX_H +#define _NTP_TIMEX_H + +/* + * Include system timex.h (if appropriate) + */ +#ifdef HAVE_SYS_TIMEX_H +#include <sys/timex.h> +#else /* provide definitions */ +#include <sys/syscall.h> + +extern int syscall P((int, void *, ...)); + +#define ntp_gettime(t) syscall(SYS_ntp_gettime, (t)) +#define ntp_adjtime(t) syscall(SYS_ntp_adjtime, (t)) + +/* + * The following defines establish the engineering parameters of the PLL + * model. The HZ variable establishes the timer interrupt frequency, 100 Hz + * for the SunOS kernel, 256 Hz for the Ultrix kernel and 1024 Hz for the + * OSF/1 kernel. The SHIFT_HZ define expresses the same value as the + * nearest power of two in order to avoid hardware multiply operations. + */ +#define SHIFT_HZ 7 /* log2(HZ) */ + +/* + * The SHIFT_KG and SHIFT_KF defines establish the damping of the PLL + * and are chosen by analysis for a slightly underdamped convergence + * characteristic. The MAXTC define establishes the maximum time constant + * of the PLL. With the parameters given and the default time constant of + * zero, the PLL will converge in about 15 minutes. + */ +#define SHIFT_KG 6 /* shift for phase increment */ +#define SHIFT_KF 16 /* shift for frequency increment */ +#define MAXTC 6 /* maximum time constant (shift) */ + +/* + * The SHIFT_SCALE define establishes the decimal point of the time_phase + * variable which serves as a an extension to the low-order bits of the + * system clock variable. The SHIFT_UPDATE define establishes the decimal + * point of the time_offset variable which represents the current offset + * with respect to standard time. The SHIFT_USEC define represents 1 us in + * external units (shift), while the FINEUSEC define represents 1 us in + * internal units. + */ +#define SHIFT_SCALE 23 /* shift for phase scale factor */ +#define SHIFT_UPDATE (SHIFT_KG + MAXTC) /* shift for offset scale factor */ +#define SHIFT_USEC 16 /* shift for 1 us in external units */ +#define FINEUSEC (1 << SHIFT_SCALE) /* 1 us in internal units */ + +/* + * Mode codes (timex.mode) + */ +#define ADJ_OFFSET 0x0001 /* time offset */ +#define ADJ_FREQUENCY 0x0002 /* frequency offset */ +#define ADJ_MAXERROR 0x0004 /* maximum time error */ +#define ADJ_ESTERROR 0x0008 /* estimated time error */ +#define ADJ_STATUS 0x0010 /* clock status */ +#define ADJ_TIMECONST 0x0020 /* pll time constant */ + +/* + * Clock command/status codes (timex.status) + */ +#define TIME_OK 0 /* clock synchronized */ +#define TIME_INS 1 /* insert leap second */ +#define TIME_DEL 2 /* delete leap second */ +#define TIME_OOP 3 /* leap second in progress */ +#define TIME_BAD 4 /* clock not synchronized */ + +/* + * NTP user interface - used to read kernel clock values + * Note: maximum error = NTP synch distance = dispersion + delay / 2; + * estimated error = NTP dispersion. + */ +struct ntptimeval { + struct timeval time; /* current time */ + long maxerror; /* maximum error (usec) */ + long esterror; /* estimated error (usec) */ +}; + +/* + * NTP daemon interface - used to discipline kernel clock oscillator + */ +struct timex { + int mode; /* mode selector */ + long offset; /* time offset (usec) */ + long frequency; /* frequency offset (scaled ppm) */ + long maxerror; /* maximum error (usec) */ + long esterror; /* estimated error (usec) */ + int status; /* clock command/status */ + long time_constant; /* pll time constant */ + long precision; /* clock precision (usec) (read only) */ + long tolerance; /* clock frequency tolerance (ppm) + * (read only) + */ +}; + +#endif /* HAVE_SYS_TIMEX_H */ + +#endif /* _NTP_TIMEX_H */ + |
