/*
* Reference clock support is provided here by maintaining the fiction
* that the clock is actually a peer. As no packets are exchanged with
* a reference clock, however, we replace the transmit, receive and
* packet procedures with separate code to simulate them. Routines
* refclock_transmit() and refclock_receive() maintain the peer
* variables in a state analogous to an actual peer and pass reference
* clock data on through the filters. Routines refclock_peer() and
* refclock_unpeer() are called to initialize and terminate reference
* clock associations. A set of utility routines is included to open
* serial devices, process sample data, and to perform various debugging
* functions.
*
* The main interface used by these routines is the refclockproc
* structure, which contains for most drivers the decimal equivalants
* of the year, day, month, hour, second and millisecond/microsecond
* decoded from the ASCII timecode. Additional information includes
* the receive timestamp, exception report, statistics tallies, etc.
* In addition, there may be a driver-specific unit structure used for
* local control of the device.
*
* The support routines are passed a pointer to the peer structure,
* which is used for all peer-specific processing and contains a
* pointer to the refclockproc structure, which in turn contains a
* pointer to the unit structure, if used. The peer structure is
* identified by an interface address in the dotted quad form
* 127.127.t.u, where t is the clock type and u the unit.
*/
#define FUDGEFAC .1 /* fudge correction factor */
#define LF 0x0a /* ASCII LF */
/*
* refclock_report - note the occurance of an event
*
* This routine presently just remembers the report and logs it, but
* does nothing heroic for the trap handler. It tries to be a good
* citizen and bothers the system log only if things change.
*/
void
refclock_report(
struct peer *peer,
int code
)
{
struct refclockproc *pp;
pp = peer->procptr;
if (pp == NULL)
return;
switch (code) {
case CEVNT_TIMEOUT:
pp->noreply++;
break;
case CEVNT_BADREPLY:
pp->badformat++;
break;
case CEVNT_FAULT:
break;
case CEVNT_BADDATE:
case CEVNT_BADTIME:
pp->baddata++;
break;
/*
* init_refclock - initialize the reference clock drivers
*
* This routine calls each of the drivers in turn to initialize internal
* variables, if necessary. Most drivers have nothing to say at this
* point.
*/
void
init_refclock(void)
{
int i;
for (i = 0; i < (int)num_refclock_conf; i++)
if (refclock_conf[i]->clock_init != noentry)
(refclock_conf[i]->clock_init)();
}
/*
* refclock_newpeer - initialize and start a reference clock
*
* This routine allocates and initializes the interface structure which
* supports a reference clock in the form of an ordinary NTP peer. A
* driver-specific support routine completes the initialization, if
* used. Default peer variables which identify the clock and establish
* its reference ID and stratum are set here. It returns one if success
* and zero if the clock address is invalid or already running,
* insufficient resources are available or the driver declares a bum
* rap.
*/
int
refclock_newpeer(
struct peer *peer /* peer structure pointer */
)
{
struct refclockproc *pp;
u_char clktype;
int unit;
/*
* Check for valid clock address. If already running, shut it
* down first.
*/
if (!ISREFCLOCKADR(&peer->srcadr)) {
msyslog(LOG_ERR,
"refclock_newpeer: clock address %s invalid",
stoa(&peer->srcadr));
return (0);
}
clktype = (u_char)REFCLOCKTYPE(&peer->srcadr);
unit = REFCLOCKUNIT(&peer->srcadr);
if (clktype >= num_refclock_conf ||
refclock_conf[clktype]->clock_start == noentry) {
msyslog(LOG_ERR,
"refclock_newpeer: clock type %d invalid\n",
clktype);
return (0);
}
/*
* Set peer.pmode based on the hmode. For appearances only.
*/
switch (peer->hmode) {
case MODE_ACTIVE:
peer->pmode = MODE_PASSIVE;
break;
default:
peer->pmode = MODE_SERVER;
break;
}
/*
* Do driver dependent initialization. The above defaults
* can be wiggled, then finish up for consistency.
*/
if (!((refclock_conf[clktype]->clock_start)(unit, peer))) {
refclock_unpeer(peer);
return (0);
}
peer->refid = pp->refid;
return (1);
}
/*
* refclock_unpeer - shut down a clock
*/
void
refclock_unpeer(
struct peer *peer /* peer structure pointer */
)
{
u_char clktype;
int unit;
/*
* Wiggle the driver to release its resources, then give back
* the interface structure.
*/
if (NULL == peer->procptr)
return;
clktype = peer->refclktype;
unit = peer->refclkunit;
if (refclock_conf[clktype]->clock_shutdown != noentry)
(refclock_conf[clktype]->clock_shutdown)(unit, peer);
free(peer->procptr);
peer->procptr = NULL;
}
/*
* refclock_timer - called once per second for housekeeping.
*/
void
refclock_timer(
struct peer *p
)
{
struct refclockproc * pp;
int unit;
unit = p->refclkunit;
pp = p->procptr;
if (pp->conf->clock_timer != noentry)
(*pp->conf->clock_timer)(unit, p);
if (pp->action != NULL && pp->nextaction <= current_time)
(*pp->action)(p);
}
/*
* refclock_transmit - simulate the transmit procedure
*
* This routine implements the NTP transmit procedure for a reference
* clock. This provides a mechanism to call the driver at the NTP poll
* interval, as well as provides a reachability mechanism to detect a
* broken radio or other madness.
*/
void
refclock_transmit(
struct peer *peer /* peer structure pointer */
)
{
u_char clktype;
int unit;
clktype = peer->refclktype;
unit = peer->refclkunit;
peer->sent++;
get_systime(&peer->xmt);
/*
* This is a ripoff of the peer transmit routine, but
* specialized for reference clocks. We do a little less
* protocol here and call the driver-specific transmit routine.
*/
if (peer->burst == 0) {
u_char oreach;
#ifdef DEBUG
if (debug)
printf("refclock_transmit: at %ld %s\n",
current_time, stoa(&(peer->srcadr)));
#endif
/*
* Update reachability and poll variables like the
* network code.
*/
oreach = peer->reach & 0xfe;
peer->reach <<= 1;
if (!(peer->reach & 0x0f))
clock_filter(peer, 0., 0., MAXDISPERSE);
peer->outdate = current_time;
if (!peer->reach) {
if (oreach) {
report_event(PEVNT_UNREACH, peer, NULL);
peer->timereachable = current_time;
}
} else {
if (peer->flags & FLAG_BURST)
peer->burst = NSTAGE;
}
} else {
peer->burst--;
}
peer->procptr->inpoll = TRUE;
if (refclock_conf[clktype]->clock_poll != noentry)
(refclock_conf[clktype]->clock_poll)(unit, peer);
poll_update(peer, peer->hpoll, 0);
}
/*
* Compare two doubles - used with qsort()
*/
static int
refclock_cmpl_fp(
const void *p1,
const void *p2
)
{
const double *dp1 = (const double *)p1;
const double *dp2 = (const double *)p2;
if (*dp1 < *dp2)
return -1;
if (*dp1 > *dp2)
return 1;
return 0;
}
/*
* Get number of available samples
*/
int
refclock_samples_avail(
struct refclockproc const * pp
)
{
u_int na;
# if MAXSTAGE & (MAXSTAGE - 1)
na = pp->coderecv - pp->codeproc;
if (na > MAXSTAGE)
na += MAXSTAGE;
# else
na = (pp->coderecv - pp->codeproc) & (MAXSTAGE - 1);
# endif
return na;
}
/*
* Expire (remove) samples from the tail (oldest samples removed)
*
* Returns number of samples deleted
*/
int
refclock_samples_expire(
struct refclockproc * pp,
int nd
)
{
u_int na;
if (nd <= 0)
return 0;
# if MAXSTAGE & (MAXSTAGE - 1)
na = pp->coderecv - pp->codeproc;
if (na > MAXSTAGE)
na += MAXSTAGE;
if ((u_int)nd < na)
nd = na;
pp->codeproc = (pp->codeproc + nd) % MAXSTAGE;
/*
* refclock_process_offset - update median filter
*
* This routine uses the given offset and timestamps to construct a new
* entry in the median filter circular buffer. Samples that overflow the
* filter are quietly discarded.
*/
void
refclock_process_offset(
struct refclockproc *pp, /* refclock structure pointer */
l_fp lasttim, /* last timecode timestamp */
l_fp lastrec, /* last receive timestamp */
double fudge
)
{
l_fp lftemp;
double doffset;
/*
* refclock_process - process a sample from the clock
* refclock_process_f - refclock_process with other than time1 fudge
*
* This routine converts the timecode in the form days, hours, minutes,
* seconds and milliseconds/microseconds to internal timestamp format,
* then constructs a new entry in the median filter circular buffer.
* Return success (1) if the data are correct and consistent with the
* conventional calendar.
*
* Important for PPS users: Normally, the pp->lastrec is set to the
* system time when the on-time character is received and the pp->year,
* ..., pp->second decoded and the seconds fraction pp->nsec in
* nanoseconds). When a PPS offset is available, pp->nsec is forced to
* zero and the fraction for pp->lastrec is set to the PPS offset.
*/
int
refclock_process_f(
struct refclockproc *pp, /* refclock structure pointer */
double fudge
)
{
l_fp offset, ltemp;
/*
* Compute the timecode timestamp from the days, hours, minutes,
* seconds and milliseconds/microseconds of the timecode. Use
* clocktime() for the aggregate seconds and the msec/usec for
* the fraction, when present. Note that this code relies on the
* file system time for the years and does not use the years of
* the timecode.
*/
if (!clocktime(pp->day, pp->hour, pp->minute, pp->second, GMT,
pp->lastrec.l_ui, &pp->yearstart, &offset.l_ui))
return (0);
/*
* refclock_sample - process a pile of samples from the clock
*
* This routine implements a recursive median filter to suppress spikes
* in the data, as well as determine a performance statistic. It
* calculates the mean offset and RMS jitter. A time adjustment
* fudgetime1 can be added to the final offset to compensate for various
* systematic errors. The routine returns the number of samples
* processed, which could be zero.
*/
static int
refclock_sample(
struct refclockproc *pp /* refclock structure pointer */
)
{
size_t i, j, k, m, n;
double off[MAXSTAGE];
/*
* Copy the raw offsets and sort into ascending order. Don't do
* anything if the buffer is empty.
*/
n = 0;
while (pp->codeproc != pp->coderecv)
off[n++] = clk_pop_sample(pp);
if (n == 0)
return (0);
if (n > 1)
qsort(off, n, sizeof(off[0]), refclock_cmpl_fp);
/*
* Reject the furthest from the median of the samples until
* approximately 60 percent of the samples remain.
*
* [Bug 3672] The elimination is now based on the proper
* definition of the median. The true median is not calculated
* directly, though.
*/
i = 0; j = n;
m = n - (n * 4) / 10;
while ((k = j - i) > m) {
k = (k - 1) >> 1;
if ((off[j - 1] - off[j - k - 1]) < (off[i + k] - off[i]))
i++; /* reject low end */
else
j--; /* reject high end */
}
/*
* Determine the offset and jitter.
*/
pp->offset = off[i];
pp->jitter = 0;
for (k = i + 1; k < j; k++) {
pp->offset += off[k];
pp->jitter += SQUARE(off[k] - off[k - 1]);
}
pp->offset /= m;
m -= (m > 1); /* only (m-1) terms attribute to jitter! */
pp->jitter = max(SQRT(pp->jitter / m), LOGTOD(sys_precision));
/*
* If the source has a jitter that cannot be estimated, because
* it is not statistic jitter, the source will be detected as
* falseticker sooner or later. Enforcing a minimal jitter value
* avoids a too low estimation while still detecting higher jitter.
*
* Note that this changes the refclock samples and ends up in the
* clock dispersion, not the clock jitter, despite being called
* jitter. To see the modified values, check the NTP clock variable
* "filtdisp", not "jitter".
*/
pp->jitter = max(pp->jitter, pp->fudgeminjitter);
/*
* refclock_receive - simulate the receive and packet procedures
*
* This routine simulates the NTP receive and packet procedures for a
* reference clock. This provides a mechanism in which the ordinary NTP
* filter, selection and combining algorithms can be used to suppress
* misbehaving radios and to mitigate between them when more than one is
* available for backup.
*/
void
refclock_receive(
struct peer *peer /* peer structure pointer */
)
{
struct refclockproc *pp;
#ifdef DEBUG
if (debug)
printf("refclock_receive: at %lu %s\n",
current_time, stoa(&peer->srcadr));
#endif
/*
* Do a little sanity dance and update the peer structure. Groom
* the median filter samples and give the data to the clock
* filter.
*/
pp = peer->procptr;
pp->inpoll = FALSE;
peer->leap = pp->leap;
if (peer->leap == LEAP_NOTINSYNC)
return;
/*
* refclock_gtlin - groom next input line and extract timestamp
*
* This routine processes the timecode received from the clock and
* strips the parity bit and control characters. It returns the number
* of characters in the line followed by a NULL character ('\0'), which
* is not included in the count. In case of an empty line, the previous
* line is preserved.
*/
int
refclock_gtlin(
struct recvbuf *rbufp, /* receive buffer pointer */
char *lineptr, /* current line pointer */
int bmax, /* remaining characters in line */
l_fp *tsptr /* pointer to timestamp returned */
)
{
const char *sp, *spend;
char *dp, *dpend;
int dlen;
c = *sp++ & 0x7f;
if (c >= 0x20 && c < 0x7f)
*dp++ = c;
}
/* Get length of data written to the destination buffer. If
* zero, do *not* place a NUL byte to preserve the previous
* buffer content.
*/
dlen = dp - lineptr;
if (dlen)
*dp = '\0';
*tsptr = rbufp->recv_time;
DPRINTF(2, ("refclock_gtlin: fd %d time %s timecode %d %s\n",
rbufp->fd, ulfptoa(&rbufp->recv_time, 6), dlen,
(dlen != 0)
? lineptr
: ""));
return (dlen);
}
/*
* refclock_gtraw - get next line/chunk of data
*
* This routine returns the raw data received from the clock in both
* canonical or raw modes. The terminal interface routines map CR to LF.
* In canonical mode this results in two lines, one containing data
* followed by LF and another containing only LF. In raw mode the
* interface routines can deliver arbitraty chunks of data from one
* character to a maximum specified by the calling routine. In either
* mode the routine returns the number of characters in the line
* followed by a NULL character ('\0'), which is not included in the
* count.
*
* *tsptr receives a copy of the buffer timestamp.
*/
int
refclock_gtraw(
struct recvbuf *rbufp, /* receive buffer pointer */
char *lineptr, /* current line pointer */
int bmax, /* remaining characters in line */
l_fp *tsptr /* pointer to timestamp returned */
)
{
if (bmax <= 0)
return (0);
bmax -= 1; /* leave room for trailing NUL */
if (bmax > rbufp->recv_length)
bmax = rbufp->recv_length;
memcpy(lineptr, rbufp->recv_buffer, bmax);
lineptr[bmax] = '\0';
/*
* refclock_fdwrite()
*
* Write data to a clock device. Does the necessary result checks and
* logging, and encapsulates OS dependencies.
*/
#ifdef SYS_WINNT
extern int async_write(int fd, const void * buf, unsigned int len);
#endif
size_t
refclock_fdwrite(
const struct peer * peer,
int fd,
const void * buf,
size_t len,
const char * what
)
{
size_t nret, nout;
int nerr;
/*
* indicate_refclock_packet()
*
* Passes a fragment of refclock input read from the device to the
* driver direct input routine, which may consume it (batch it for
* queuing once a logical unit is assembled). If it is not so
* consumed, queue it for the driver's receive entrypoint.
*
* The return value is TRUE if the data has been consumed as a fragment
* and should not be counted as a received packet.
*/
int
indicate_refclock_packet(
struct refclockio * rio,
struct recvbuf * rb
)
{
/* Does this refclock use direct input routine? */
if (rio->io_input != NULL && (*rio->io_input)(rb) == 0) {
/*
* data was consumed - nothing to pass up
* into block input machine
*/
freerecvbuf(rb);
return TRUE;
}
add_full_recv_buffer(rb);
return FALSE;
}
/*
* process_refclock_packet()
*
* Used for deferred processing of 'io_input' on systems where threading
* is used (notably Windows). This is acting as a trampoline to make the
* real calls to the refclock functions.
*/
#ifdef HAVE_IO_COMPLETION_PORT
void
process_refclock_packet(
struct recvbuf * rb
)
{
struct refclockio * rio;
/* get the refclockio structure from the receive buffer */
rio = &rb->recv_peer->procptr->io;
/* call 'clock_recv' if either there is no input function or the
* raw input function tells us to feed the packet to the
* receiver.
*/
if (rio->io_input == NULL || (*rio->io_input)(rb) != 0) {
rio->recvcount++;
packets_received++;
handler_pkts++;
(*rio->clock_recv)(rb);
}
}
#endif /* HAVE_IO_COMPLETION_PORT */
/*
* The following code does not apply to WINNT & VMS ...
*/
#if !defined(SYS_VXWORKS) && !defined(SYS_WINNT)
#if defined(HAVE_TERMIOS) || defined(HAVE_SYSV_TTYS) || defined(HAVE_BSD_TTYS)
/*
* refclock_open - open serial port for reference clock
*
* This routine opens a serial port for I/O and sets default options. It
* returns the file descriptor if successful, or logs an error and
* returns -1.
*/
int
refclock_open(
const sockaddr_u *srcadr,
const char *dev, /* device name pointer */
u_int speed, /* serial port speed (code) */
u_int lflags /* line discipline flags */
)
{
const char *cdev;
int fd;
int omode;
#ifdef O_NONBLOCK
char trash[128]; /* litter bin for old input data */
#endif
/*
* Open serial port and set default options
*/
omode = O_RDWR;
#ifdef O_NONBLOCK
omode |= O_NONBLOCK;
#endif
#ifdef O_NOCTTY
omode |= O_NOCTTY;
#endif
if (NULL != (cdev = clockdev_lookup(srcadr, 0)))
dev = cdev;
fd = open(dev, omode, 0777);
/* refclock_open() long returned 0 on failure, avoid it. */
if (0 == fd) {
fd = dup(0);
SAVE_ERRNO(
close(0);
)
}
if (fd < 0) {
SAVE_ERRNO(
msyslog(LOG_ERR, "refclock_open %s: %m", dev);
)
return -1;
}
if (!refclock_setup(fd, speed, lflags)) {
close(fd);
return -1;
}
if (!refclock_ioctl(fd, lflags)) {
close(fd);
return -1;
}
msyslog(LOG_NOTICE, "%s serial %s open at %d bps",
refnumtoa(srcadr), dev, symBaud2numBaud(speed));
#ifdef O_NONBLOCK
/*
* We want to make sure there is no pending trash in the input
* buffer. Since we have non-blocking IO available, this is a
* good moment to read and dump all available outdated stuff
* that might have become toxic for the driver.
*/
while (read(fd, trash, sizeof(trash)) > 0 || errno == EINTR)
/*NOP*/;
#endif
return fd;
}
/*
* refclock_setup - initialize terminal interface structure
*/
int
refclock_setup(
int fd, /* file descriptor */
u_int speed, /* serial port speed (code) */
u_int lflags /* line discipline flags */
)
{
int i;
TTY ttyb, *ttyp;
/*
* By default, the serial line port is initialized in canonical
* (line-oriented) mode at specified line speed, 8 bits and no
* parity. LF ends the line and CR is mapped to LF. The break,
* erase and kill functions are disabled. There is a different
* section for each terminal interface, as selected at compile
* time. The flag bits can be used to set raw mode and echo.
*/
ttyp = &ttyb;
#ifdef HAVE_TERMIOS
/*
* POSIX serial line parameters (termios interface)
*/
if (tcgetattr(fd, ttyp) < 0) {
SAVE_ERRNO(
msyslog(LOG_ERR,
"refclock_setup fd %d tcgetattr: %m",
fd);
)
return FALSE;
}
/*
* Set canonical mode and local connection; set specified speed,
* 8 bits and no parity; map CR to NL; ignore break.
*/
if (speed) {
u_int ltemp = 0;
/*
* If we have modem control, check to see if modem leads
* are active; if so, set remote connection. This is
* necessary for the kernel pps mods to work.
*/
if (ioctl(fd, TIOCMGET, (char *)<emp) < 0)
msyslog(LOG_ERR,
"refclock_setup fd %d TIOCMGET: %m", fd);
#ifdef DEBUG
if (debug)
printf("refclock_setup fd %d modem status: 0x%x\n",
fd, ltemp);
#endif
if (ltemp & TIOCM_DSR && lflags & LDISC_REMOTE)
ttyp->c_cflag &= ~CLOCAL;
#endif /* TIOCMGET */
}
/*
* Set raw and echo modes. These can be changed on-fly.
*/
ttyp->c_lflag = ICANON;
if (lflags & LDISC_RAW) {
ttyp->c_lflag = 0;
ttyp->c_iflag = 0;
ttyp->c_cc[VMIN] = 1;
}
if (lflags & LDISC_ECHO)
ttyp->c_lflag |= ECHO;
if (tcsetattr(fd, TCSANOW, ttyp) < 0) {
SAVE_ERRNO(
msyslog(LOG_ERR,
"refclock_setup fd %d TCSANOW: %m",
fd);
)
return FALSE;
}
/*
* flush input and output buffers to discard any outdated stuff
* that might have become toxic for the driver. Failing to do so
* is logged, but we keep our fingers crossed otherwise.
*/
if (tcflush(fd, TCIOFLUSH) < 0)
msyslog(LOG_ERR, "refclock_setup fd %d tcflush(): %m",
fd);
#endif /* HAVE_TERMIOS */
#ifdef HAVE_SYSV_TTYS
/*
* System V serial line parameters (termio interface)
*
*/
if (ioctl(fd, TCGETA, ttyp) < 0) {
SAVE_ERRNO(
msyslog(LOG_ERR,
"refclock_setup fd %d TCGETA: %m",
fd);
)
return FALSE;
}
/*
* Set canonical mode and local connection; set specified speed,
* 8 bits and no parity; map CR to NL; ignore break.
*/
if (speed) {
u_int ltemp = 0;
ttyp->c_iflag = IGNBRK | IGNPAR | ICRNL;
ttyp->c_oflag = 0;
ttyp->c_cflag = speed | CS8 | CLOCAL | CREAD;
for (i = 0; i < NCCS; ++i)
ttyp->c_cc[i] = '\0';
#if defined(TIOCMGET) && !defined(SCO5_CLOCK)
/*
* If we have modem control, check to see if modem leads
* are active; if so, set remote connection. This is
* necessary for the kernel pps mods to work.
*/
if (ioctl(fd, TIOCMGET, (char *)<emp) < 0)
msyslog(LOG_ERR,
"refclock_setup fd %d TIOCMGET: %m", fd);
#ifdef DEBUG
if (debug)
printf("refclock_setup fd %d modem status: %x\n",
fd, ltemp);
#endif
if (ltemp & TIOCM_DSR)
ttyp->c_cflag &= ~CLOCAL;
#endif /* TIOCMGET */
}
/*
* Set raw and echo modes. These can be changed on-fly.
*/
ttyp->c_lflag = ICANON;
if (lflags & LDISC_RAW) {
ttyp->c_lflag = 0;
ttyp->c_iflag = 0;
ttyp->c_cc[VMIN] = 1;
}
if (ioctl(fd, TCSETA, ttyp) < 0) {
SAVE_ERRNO(
msyslog(LOG_ERR,
"refclock_setup fd %d TCSETA: %m", fd);
)
return FALSE;
}
#endif /* HAVE_SYSV_TTYS */
/*
* refclock_ioctl - set serial port control functions
*
* This routine attempts to hide the internal, system-specific details
* of serial ports. It can handle POSIX (termios), SYSV (termio) and BSD
* (sgtty) interfaces with varying degrees of success. The routine sets
* up optional features such as tty_clk. The routine returns TRUE if
* successful.
*/
int
refclock_ioctl(
int fd, /* file descriptor */
u_int lflags /* line discipline flags */
)
{
/*
* simply return TRUE if no UNIX line discipline is supported
*/
DPRINTF(1, ("refclock_ioctl: fd %d flags 0x%x\n", fd, lflags));
/*
* refclock_control - set and/or return clock values
*
* This routine is used mainly for debugging. It returns designated
* values from the interface structure that can be displayed using
* ntpdc and the clockstat command. It can also be used to initialize
* configuration variables, such as fudgetimes, fudgevalues, reference
* ID and stratum.
*/
void
refclock_control(
sockaddr_u *srcadr,
const struct refclockstat *in,
struct refclockstat *out
)
{
struct peer *peer;
struct refclockproc *pp;
u_char clktype;
int unit;
/*
* Check for valid address and running peer
*/
if (!ISREFCLOCKADR(srcadr))
return;
clktype = (u_char)REFCLOCKTYPE(srcadr);
unit = REFCLOCKUNIT(srcadr);
/*
* Give the stuff to the clock
*/
if (refclock_conf[clktype]->clock_control != noentry)
(refclock_conf[clktype]->clock_control)(unit, in, out, peer);
}
/*
* refclock_buginfo - return debugging info
*
* This routine is used mainly for debugging. It returns designated
* values from the interface structure that can be displayed using
* ntpdc and the clkbug command.
*/
void
refclock_buginfo(
sockaddr_u *srcadr, /* clock address */
struct refclockbug *bug /* output structure */
)
{
struct peer *peer;
struct refclockproc *pp;
int clktype;
int unit;
unsigned u;
/*
* Check for valid address and peer structure
*/
if (!ISREFCLOCKADR(srcadr))
return;
clktype = (u_char) REFCLOCKTYPE(srcadr);
unit = REFCLOCKUNIT(srcadr);
/*
* Give the stuff to the clock
*/
if (refclock_conf[clktype]->clock_buginfo != noentry)
(refclock_conf[clktype]->clock_buginfo)(unit, bug, peer);
}
#ifdef HAVE_PPSAPI
/*
* refclock_ppsapi - initialize/update ppsapi
*
* This routine is called after the fudge command to open the PPSAPI
* interface for later parameter setting after the fudge command.
*/
int
refclock_ppsapi(
int fddev, /* fd device */
struct refclock_atom *ap /* atom structure pointer */
)
{
if (ap->handle == 0) {
if (time_pps_create(fddev, &ap->handle) < 0) {
msyslog(LOG_ERR,
"refclock_ppsapi: time_pps_create: %m");
return (0);
}
ZERO(ap->ts); /* [Bug 2689] defined INIT state */
}
return (1);
}
/*
* refclock_params - set ppsapi parameters
*
* This routine is called to set the PPSAPI parameters after the fudge
* command.
*/
int
refclock_params(
int mode, /* mode bits */
struct refclock_atom *ap /* atom structure pointer */
)
{
ZERO(ap->pps_params);
ap->pps_params.api_version = PPS_API_VERS_1;
/*
* Solaris serial ports provide PPS pulse capture only on the
* assert edge. FreeBSD serial ports provide capture on the
* clear edge, while FreeBSD parallel ports provide capture
* on the assert edge. Your mileage may vary.
*/
if (mode & CLK_FLAG2)
ap->pps_params.mode = PPS_TSFMT_TSPEC | PPS_CAPTURECLEAR;
else
ap->pps_params.mode = PPS_TSFMT_TSPEC | PPS_CAPTUREASSERT;
if (time_pps_setparams(ap->handle, &ap->pps_params) < 0) {
msyslog(LOG_ERR,
"refclock_params: time_pps_setparams: %m");
return (0);
}
/*
* If flag3 is lit, select the kernel PPS if we can.
*
* Note: EOPNOTSUPP is the only 'legal' error code we deal with;
* it is part of the 'if we can' strategy. Any other error
* indicates something more sinister and makes this function fail.
*/
if (mode & CLK_FLAG3) {
if (time_pps_kcbind(ap->handle, PPS_KC_HARDPPS,
ap->pps_params.mode & ~PPS_TSFMT_TSPEC,
PPS_TSFMT_TSPEC) < 0)
{
if (errno != EOPNOTSUPP) {
msyslog(LOG_ERR,
"refclock_params: time_pps_kcbind: %m");
return (0);
}
} else {
hardpps_enable = 1;
}
}
return (1);
}
/*
* refclock_pps - called once per second
*
* This routine is called once per second. It snatches the PPS
* timestamp from the kernel and saves the sign-extended fraction in
* a circular buffer for processing at the next poll event.
*/
int
refclock_pps(
struct peer *peer, /* peer structure pointer */
struct refclock_atom *ap, /* atom structure pointer */
int mode /* mode bits */
)
{
struct refclockproc *pp;
pps_info_t pps_info;
struct timespec timeout;
double dtemp, dcorr, trash;
/*
* We require the clock to be synchronized before setting the
* parameters. When the parameters have been set, fetch the
* most recent PPS timestamp.
*/
pp = peer->procptr;
if (ap->handle == 0)
return (0);
if (ap->pps_params.mode == 0 && sys_leap != LEAP_NOTINSYNC) {
if (refclock_params(pp->sloppyclockflag, ap) < 1)
return (0);
}
ZERO(timeout);
ZERO(pps_info);
if (time_pps_fetch(ap->handle, PPS_TSFMT_TSPEC, &pps_info,
&timeout) < 0) {
refclock_report(peer, CEVNT_FAULT);
return (0);
}
timeout = ap->ts; /* save old timestamp for check */
if (ap->pps_params.mode & PPS_CAPTUREASSERT)
ap->ts = pps_info.assert_timestamp;
else if (ap->pps_params.mode & PPS_CAPTURECLEAR)
ap->ts = pps_info.clear_timestamp;
else
return (0);
/* [Bug 2689] Discard the first sample we read -- if the PPS
* source is currently down / disconnected, we have read a
* potentially *very* stale value here. So if our old TS value
* is all-zero, we consider this sample unrealiable and drop it.
*
* Note 1: a better check would compare the PPS time stamp to
* the current system time and drop it if it's more than say 3s
* away.
*
* Note 2: If we ever again get an all-zero PPS sample, the next
* one will be discarded. This can happen every 136yrs and is
* unlikely to be ever observed.
*/
if (0 == (timeout.tv_sec | timeout.tv_nsec))
return (0);
/* If the PPS source fails to deliver a new sample between
* polls, it regurgitates the last sample. We do not want to
* process the same sample multiple times.
*/
if (0 == memcmp(&timeout, &ap->ts, sizeof(timeout)))
return (0);
/*
* Convert to signed fraction offset, apply fudge and properly
* fold the correction into the [-0.5s,0.5s] range. Handle
* excessive fudge times, too.
*/
dtemp = ap->ts.tv_nsec / 1e9;
dcorr = modf((pp->fudgetime1 - dtemp), &trash);
if (dcorr > 0.5)
dcorr -= 1.0;
else if (dcorr < -0.5)
dcorr += 1.0;
/* phase gate check: avoid wobbling by +/-1s when too close to
* the switch-over point. We allow +/-400ms max phase deviation.
* The trade-off is clear: The smaller the limit, the less
* sensitive to sampling noise the clock becomes. OTOH the
* system must get into phase gate range by other means for the
* PPS clock to lock in.
*/
if (fabs(dcorr) > 0.4)
return (0);
/*
* record this time stamp and stuff in median filter
*/
pp->lastrec.l_ui = (u_int32)ap->ts.tv_sec + JAN_1970;
pp->lastrec.l_uf = (u_int32)(dtemp * FRAC);
clk_add_sample(pp, dcorr);
refclock_checkburst(peer, pp);
/*
* -------------------------------------------------------------------
* refclock_ppsaugment(...) -- correlate with PPS edge
*
* This function is used to correlate a receive time stamp with a PPS
* edge time stamp. It applies the necessary fudges and then tries to
* move the receive time stamp to the corresponding edge. This can warp
* into future, if a transmission delay of more than 500ms is not
* compensated with a corresponding fudge time2 value, because then the
* next PPS edge is nearer than the last. (Similiar to what the PPS ATOM
* driver does, but we deal with full time stamps here, not just phase
* shift information.) Likewise, a negative fudge time2 value must be
* used if the reference time stamp correlates with the *following* PPS
* pulse.
*
* Note that the receive time fudge value only needs to move the receive
* stamp near a PPS edge but that close proximity is not required;
* +/-100ms precision should be enough. But since the fudge value will
* probably also be used to compensate the transmission delay when no
* PPS edge can be related to the time stamp, it's best to get it as
* close as possible.
*
* It should also be noted that the typical use case is matching to the
* preceeding edge, as most units relate their sentences to the current
* second.
*
* The function returns FALSE if there is no correlation possible, TRUE
* otherwise. Reason for failures are:
*
* - no PPS/ATOM unit given
* - PPS stamp is stale (that is, the difference between the PPS stamp
* and the corrected time stamp would exceed two seconds)
* - The phase difference is too close to 0.5, and the decision wether
* to move up or down is too sensitive to noise.
*
* On output, the receive time stamp is updated with the 'fixed' receive
* time.
* -------------------------------------------------------------------
*/
/* fixup receive time in case we have to bail out early */
DTOLFP(rcvfudge, delta);
L_SUB(rcvtime, delta);
if (NULL == ap)
return FALSE;
ZERO(timeout);
ZERO(pps_info);
/* fetch PPS stamp from ATOM block */
if (time_pps_fetch(ap->handle, PPS_TSFMT_TSPEC,
&pps_info, &timeout) < 0)
return FALSE; /* can't get time stamps */
/* get last active PPS edge before receive */
if (ap->pps_params.mode & PPS_CAPTUREASSERT)
timeout = pps_info.assert_timestamp;
else if (ap->pps_params.mode & PPS_CAPTURECLEAR)
timeout = pps_info.clear_timestamp;
else
return FALSE; /* WHICH edge, please?!? */
/* convert PPS stamp to l_fp and apply fudge */
*stamp = tspec_stamp_to_lfp(timeout);
DTOLFP(ppsfudge, delta);
L_SUB(stamp, delta);
/* Get difference between PPS stamp (--> yield) and receive time
* (--> base)
*/
*delta = *stamp;
L_SUB(delta, rcvtime);
/* check if either the PPS or the STAMP is stale in relation
* to each other. Bail if it is so...
*/
phase = delta->l_ui;
if (phase >= 2 && phase < (uint32_t)-2)
return FALSE; /* PPS is stale, don't use it */
/* If the phase is too close to 0.5, the decision whether to
* move up or down is becoming noise sensitive. That is, we
* might amplify usec noise between samples into seconds with a
* simple threshold. This can be solved by a Schmitt Trigger
* characteristic, but that would also require additional state
* where we could remember previous decisions. Easier to play
* dead duck and wait for the conditions to become clear.
*/
phase = delta->l_uf;
if (phase > s_plim_hi && phase < s_plim_lo)
return FALSE; /* we're in the noise lock gap */
/* sign-extend fraction into seconds */
delta->l_ui = UINT32_C(0) - ((phase >> 31) & 1);
/* add it up now */
L_ADD(rcvtime, delta);
return TRUE;
# else /* have no PPS support at all */
/* just fixup receive time and fail */
UNUSED_ARG(ap);
UNUSED_ARG(ppsfudge);
/*
* -------------------------------------------------------------------
* check if it makes sense to schedule an 'early' poll to get the clock
* up fast after start or longer signal dropout.
*/
static void
refclock_checkburst(
struct peer * peer,
struct refclockproc * pp
)
{
uint32_t limit; /* when we should poll */
u_int needs; /* needed number of samples */
/* Paranoia: stop here if peer and clockproc don't match up.
* And when a poll is actually pending, we don't have to do
* anything, either. Likewise if the reach mask is full, of
* course, and if the filter has stabilized.
*/
if (pp->inpoll || (peer->procptr != pp) ||
((peer->reach == 0xFF) && (peer->disp <= MAXDISTANCE)))
return;
/* If the next poll is soon enough, bail out, too: */
limit = current_time + 1;
if (peer->nextdate <= limit)
return;
/* Derive the number of samples needed from the popcount of the
* reach mask. With less samples available, we break away.
*/
needs = peer->reach;
needs -= (needs >> 1) & 0x55;
needs = (needs & 0x33) + ((needs >> 2) & 0x33);
needs = (needs + (needs >> 4)) & 0x0F;
if (needs > 6)
needs = 6;
else if (needs < 3)
needs = 3;
if (clk_cnt_sample(pp) < needs)
return;
/* Get serious. Reduce the poll to minimum and schedule early.
* (Changing the peer poll is probably in vain, as it will be
* re-adjusted, but maybe some time the hint will work...)
*/
peer->hpoll = peer->minpoll;
peer->nextdate = limit;
}
/*
* -------------------------------------------------------------------
* Save the last timecode string, making sure it's properly truncated
* if necessary and NUL terminated in any case.
*/
void
refclock_save_lcode(
struct refclockproc * pp,
char const * tc,
size_t len
)
{
if (len == (size_t)-1)
len = strnlen(tc, sizeof(pp->a_lastcode) - 1);
else if (len >= sizeof(pp->a_lastcode))
len = sizeof(pp->a_lastcode) - 1;
