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-rw-r--r--refclock.c862
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diff --git a/refclock.c b/refclock.c
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+++ b/refclock.c
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+/*
+ chronyd/chronyc - Programs for keeping computer clocks accurate.
+
+ **********************************************************************
+ * Copyright (C) Miroslav Lichvar 2009-2011, 2013-2014, 2016-2019, 2022
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ **********************************************************************
+
+ =======================================================================
+
+ Routines implementing reference clocks.
+
+ */
+
+#include "config.h"
+
+#include "array.h"
+#include "refclock.h"
+#include "reference.h"
+#include "conf.h"
+#include "local.h"
+#include "memory.h"
+#include "util.h"
+#include "sources.h"
+#include "logging.h"
+#include "regress.h"
+#include "samplefilt.h"
+#include "sched.h"
+
+/* Maximum offset of locked reference as a fraction of the PPS interval */
+#define PPS_LOCK_LIMIT 0.4
+
+/* list of refclock drivers */
+extern RefclockDriver RCL_SHM_driver;
+extern RefclockDriver RCL_SOCK_driver;
+extern RefclockDriver RCL_PPS_driver;
+extern RefclockDriver RCL_PHC_driver;
+
+struct FilterSample {
+ double offset;
+ double dispersion;
+ struct timespec sample_time;
+};
+
+struct RCL_Instance_Record {
+ RefclockDriver *driver;
+ void *data;
+ char *driver_parameter;
+ int driver_parameter_length;
+ int driver_poll;
+ int driver_polled;
+ int poll;
+ int leap_status;
+ int local;
+ int pps_forced;
+ int pps_rate;
+ int pps_active;
+ int max_lock_age;
+ int stratum;
+ int tai;
+ uint32_t ref_id;
+ uint32_t lock_ref;
+ double offset;
+ double delay;
+ double precision;
+ double pulse_width;
+ SPF_Instance filter;
+ SCH_TimeoutID timeout_id;
+ SRC_Instance source;
+};
+
+/* Array of pointers to RCL_Instance_Record */
+static ARR_Instance refclocks;
+
+static LOG_FileID logfileid;
+
+static int valid_sample_time(RCL_Instance instance, struct timespec *sample_time);
+static int pps_stratum(RCL_Instance instance, struct timespec *ts);
+static void poll_timeout(void *arg);
+static void slew_samples(struct timespec *raw, struct timespec *cooked, double dfreq,
+ double doffset, LCL_ChangeType change_type, void *anything);
+static void add_dispersion(double dispersion, void *anything);
+static void log_sample(RCL_Instance instance, struct timespec *sample_time, int filtered, int pulse, double raw_offset, double cooked_offset, double dispersion);
+
+static RCL_Instance
+get_refclock(unsigned int index)
+{
+ return *(RCL_Instance *)ARR_GetElement(refclocks, index);
+}
+
+void
+RCL_Initialise(void)
+{
+ refclocks = ARR_CreateInstance(sizeof (RCL_Instance));
+
+ CNF_AddRefclocks();
+
+ if (ARR_GetSize(refclocks) > 0) {
+ LCL_AddParameterChangeHandler(slew_samples, NULL);
+ LCL_AddDispersionNotifyHandler(add_dispersion, NULL);
+ }
+
+ logfileid = CNF_GetLogRefclocks() ? LOG_FileOpen("refclocks",
+ " Date (UTC) Time Refid DP L P Raw offset Cooked offset Disp.")
+ : -1;
+}
+
+void
+RCL_Finalise(void)
+{
+ unsigned int i;
+
+ for (i = 0; i < ARR_GetSize(refclocks); i++) {
+ RCL_Instance inst = get_refclock(i);
+
+ if (inst->driver->fini)
+ inst->driver->fini(inst);
+
+ SPF_DestroyInstance(inst->filter);
+ Free(inst->driver_parameter);
+ SRC_DestroyInstance(inst->source);
+ Free(inst);
+ }
+
+ if (ARR_GetSize(refclocks) > 0) {
+ LCL_RemoveParameterChangeHandler(slew_samples, NULL);
+ LCL_RemoveDispersionNotifyHandler(add_dispersion, NULL);
+ }
+
+ ARR_DestroyInstance(refclocks);
+}
+
+int
+RCL_AddRefclock(RefclockParameters *params)
+{
+ RCL_Instance inst;
+
+ inst = MallocNew(struct RCL_Instance_Record);
+ *(RCL_Instance *)ARR_GetNewElement(refclocks) = inst;
+
+ if (strcmp(params->driver_name, "SHM") == 0) {
+ inst->driver = &RCL_SHM_driver;
+ } else if (strcmp(params->driver_name, "SOCK") == 0) {
+ inst->driver = &RCL_SOCK_driver;
+ } else if (strcmp(params->driver_name, "PPS") == 0) {
+ inst->driver = &RCL_PPS_driver;
+ } else if (strcmp(params->driver_name, "PHC") == 0) {
+ inst->driver = &RCL_PHC_driver;
+ } else {
+ LOG_FATAL("unknown refclock driver %s", params->driver_name);
+ }
+
+ if (!inst->driver->init && !inst->driver->poll)
+ LOG_FATAL("refclock driver %s is not compiled in", params->driver_name);
+
+ if (params->tai && !CNF_GetLeapSecTimezone())
+ LOG_FATAL("refclock tai option requires leapsectz");
+
+ inst->data = NULL;
+ inst->driver_parameter = Strdup(params->driver_parameter);
+ inst->driver_parameter_length = 0;
+ inst->driver_poll = params->driver_poll;
+ inst->poll = params->poll;
+ inst->driver_polled = 0;
+ inst->leap_status = LEAP_Normal;
+ inst->local = params->local;
+ inst->pps_forced = params->pps_forced;
+ inst->pps_rate = params->pps_rate;
+ inst->pps_active = 0;
+ inst->max_lock_age = params->max_lock_age;
+ inst->stratum = params->stratum;
+ inst->tai = params->tai;
+ inst->lock_ref = params->lock_ref_id;
+ inst->offset = params->offset;
+ inst->delay = params->delay;
+ inst->precision = LCL_GetSysPrecisionAsQuantum();
+ inst->precision = MAX(inst->precision, params->precision);
+ inst->pulse_width = params->pulse_width;
+ inst->timeout_id = -1;
+ inst->source = NULL;
+
+ if (inst->driver_parameter) {
+ int i;
+
+ inst->driver_parameter_length = strlen(inst->driver_parameter);
+ for (i = 0; i < inst->driver_parameter_length; i++)
+ if (inst->driver_parameter[i] == ':')
+ inst->driver_parameter[i] = '\0';
+ }
+
+ if (inst->pps_rate < 1)
+ inst->pps_rate = 1;
+
+ if (params->ref_id)
+ inst->ref_id = params->ref_id;
+ else {
+ unsigned char ref[5] = { 0, 0, 0, 0, 0 };
+ unsigned int index = ARR_GetSize(refclocks) - 1;
+
+ snprintf((char *)ref, sizeof (ref), "%3.3s", params->driver_name);
+ ref[3] = index % 10 + '0';
+ if (index >= 10)
+ ref[2] = (index / 10) % 10 + '0';
+
+ inst->ref_id = (uint32_t)ref[0] << 24 | ref[1] << 16 | ref[2] << 8 | ref[3];
+ }
+
+ if (inst->local) {
+ inst->pps_forced = 1;
+ inst->lock_ref = inst->ref_id;
+ inst->leap_status = LEAP_Unsynchronised;
+ inst->max_lock_age = MAX(inst->max_lock_age, 3);
+ }
+
+ if (inst->driver->poll) {
+ int max_samples;
+
+ if (inst->driver_poll > inst->poll)
+ inst->driver_poll = inst->poll;
+
+ max_samples = 1 << (inst->poll - inst->driver_poll);
+ if (max_samples < params->filter_length) {
+ if (max_samples < 4) {
+ LOG(LOGS_WARN, "Setting filter length for %s to %d",
+ UTI_RefidToString(inst->ref_id), max_samples);
+ }
+ params->filter_length = max_samples;
+ }
+ }
+
+ if (inst->driver->init && !inst->driver->init(inst))
+ LOG_FATAL("refclock %s initialisation failed", params->driver_name);
+
+ /* Require the filter to have at least 4 samples to produce a filtered
+ sample, or be full for shorter lengths, and combine 60% of samples
+ closest to the median */
+ inst->filter = SPF_CreateInstance(MIN(params->filter_length, 4), params->filter_length,
+ params->max_dispersion, 0.6);
+
+ inst->source = SRC_CreateNewInstance(inst->ref_id, SRC_REFCLOCK, 0, params->sel_options,
+ NULL, params->min_samples, params->max_samples,
+ 0.0, 0.0);
+
+ DEBUG_LOG("refclock %s refid=%s poll=%d dpoll=%d filter=%d",
+ params->driver_name, UTI_RefidToString(inst->ref_id),
+ inst->poll, inst->driver_poll, params->filter_length);
+
+ return 1;
+}
+
+void
+RCL_StartRefclocks(void)
+{
+ unsigned int i, j, n, lock_index;
+
+ n = ARR_GetSize(refclocks);
+
+ for (i = 0; i < n; i++) {
+ RCL_Instance inst = get_refclock(i);
+
+ SRC_SetActive(inst->source);
+ inst->timeout_id = SCH_AddTimeoutByDelay(0.0, poll_timeout, (void *)inst);
+
+ /* Replace lock refid with the refclock's index, or -1 if not valid */
+
+ lock_index = -1;
+
+ if (inst->lock_ref != 0) {
+ for (j = 0; j < n; j++) {
+ RCL_Instance inst2 = get_refclock(j);
+
+ if (inst->lock_ref != inst2->ref_id)
+ continue;
+
+ if (inst->driver->poll && inst2->driver->poll &&
+ (double)inst->max_lock_age / inst->pps_rate < UTI_Log2ToDouble(inst2->driver_poll))
+ LOG(LOGS_WARN, "%s maxlockage too small for %s",
+ UTI_RefidToString(inst->ref_id), UTI_RefidToString(inst2->ref_id));
+
+ lock_index = j;
+ break;
+ }
+
+ if (lock_index == -1 || (lock_index == i && !inst->local))
+ LOG(LOGS_WARN, "Invalid lock refid %s", UTI_RefidToString(inst->lock_ref));
+ }
+
+ inst->lock_ref = lock_index;
+ }
+}
+
+void
+RCL_ReportSource(RPT_SourceReport *report, struct timespec *now)
+{
+ unsigned int i;
+ uint32_t ref_id;
+
+ assert(report->ip_addr.family == IPADDR_INET4);
+ ref_id = report->ip_addr.addr.in4;
+
+ for (i = 0; i < ARR_GetSize(refclocks); i++) {
+ RCL_Instance inst = get_refclock(i);
+ if (inst->ref_id == ref_id) {
+ report->poll = inst->poll;
+ report->mode = RPT_LOCAL_REFERENCE;
+ break;
+ }
+ }
+}
+
+void
+RCL_SetDriverData(RCL_Instance instance, void *data)
+{
+ instance->data = data;
+}
+
+void *
+RCL_GetDriverData(RCL_Instance instance)
+{
+ return instance->data;
+}
+
+char *
+RCL_GetDriverParameter(RCL_Instance instance)
+{
+ return instance->driver_parameter;
+}
+
+static char *
+get_next_driver_option(RCL_Instance instance, char *option)
+{
+ if (option == NULL)
+ option = instance->driver_parameter;
+
+ option += strlen(option) + 1;
+
+ if (option >= instance->driver_parameter + instance->driver_parameter_length)
+ return NULL;
+
+ return option;
+}
+
+void
+RCL_CheckDriverOptions(RCL_Instance instance, const char **options)
+{
+ char *option;
+ int i, len;
+
+ for (option = get_next_driver_option(instance, NULL);
+ option;
+ option = get_next_driver_option(instance, option)) {
+ for (i = 0; options && options[i]; i++) {
+ len = strlen(options[i]);
+ if (!strncmp(options[i], option, len) &&
+ (option[len] == '=' || option[len] == '\0'))
+ break;
+ }
+
+ if (!options || !options[i])
+ LOG_FATAL("Invalid refclock driver option %s", option);
+ }
+}
+
+char *
+RCL_GetDriverOption(RCL_Instance instance, char *name)
+{
+ char *option;
+ int len;
+
+ len = strlen(name);
+
+ for (option = get_next_driver_option(instance, NULL);
+ option;
+ option = get_next_driver_option(instance, option)) {
+ if (!strncmp(name, option, len)) {
+ if (option[len] == '=')
+ return option + len + 1;
+ if (option[len] == '\0')
+ return option + len;
+ }
+ }
+
+ return NULL;
+}
+
+static int
+convert_tai_offset(struct timespec *sample_time, double *offset)
+{
+ struct timespec tai_ts, utc_ts;
+ int tai_offset;
+
+ /* Get approximate TAI-UTC offset for the reference time in TAI */
+ UTI_AddDoubleToTimespec(sample_time, *offset, &tai_ts);
+ tai_offset = REF_GetTaiOffset(&tai_ts);
+
+ /* Get TAI-UTC offset for the reference time in UTC +/- 1 second */
+ UTI_AddDoubleToTimespec(&tai_ts, -tai_offset, &utc_ts);
+ tai_offset = REF_GetTaiOffset(&utc_ts);
+
+ if (!tai_offset)
+ return 0;
+
+ *offset -= tai_offset;
+
+ return 1;
+}
+
+static int
+accumulate_sample(RCL_Instance instance, struct timespec *sample_time, double offset, double dispersion)
+{
+ NTP_Sample sample;
+
+ sample.time = *sample_time;
+ sample.offset = offset;
+ sample.peer_delay = instance->delay;
+ sample.root_delay = instance->delay;
+ sample.peer_dispersion = dispersion;
+ sample.root_dispersion = dispersion;
+
+ return SPF_AccumulateSample(instance->filter, &sample);
+}
+
+int
+RCL_AddSample(RCL_Instance instance, struct timespec *sample_time,
+ struct timespec *ref_time, int leap)
+{
+ double correction, dispersion, raw_offset, offset;
+ struct timespec cooked_time;
+
+ if (instance->pps_forced)
+ return RCL_AddPulse(instance, sample_time,
+ 1.0e-9 * (sample_time->tv_nsec - ref_time->tv_nsec));
+
+ raw_offset = UTI_DiffTimespecsToDouble(ref_time, sample_time);
+
+ LCL_GetOffsetCorrection(sample_time, &correction, &dispersion);
+ UTI_AddDoubleToTimespec(sample_time, correction, &cooked_time);
+ dispersion += instance->precision;
+
+ /* Make sure the timestamp and offset provided by the driver are sane */
+ if (!UTI_IsTimeOffsetSane(sample_time, raw_offset) ||
+ !valid_sample_time(instance, &cooked_time))
+ return 0;
+
+ switch (leap) {
+ case LEAP_Normal:
+ case LEAP_InsertSecond:
+ case LEAP_DeleteSecond:
+ instance->leap_status = leap;
+ break;
+ default:
+ DEBUG_LOG("refclock sample ignored bad leap %d", leap);
+ return 0;
+ }
+
+ /* Calculate offset = raw_offset - correction + instance->offset
+ in parts to avoid loss of precision if there are large differences */
+ offset = ref_time->tv_sec - sample_time->tv_sec -
+ (time_t)correction + (time_t)instance->offset;
+ offset += 1.0e-9 * (ref_time->tv_nsec - sample_time->tv_nsec) -
+ (correction - (time_t)correction) + (instance->offset - (time_t)instance->offset);
+
+ if (instance->tai && !convert_tai_offset(sample_time, &offset)) {
+ DEBUG_LOG("refclock sample ignored unknown TAI offset");
+ return 0;
+ }
+
+ if (!accumulate_sample(instance, &cooked_time, offset, dispersion))
+ return 0;
+
+ instance->pps_active = 0;
+
+ log_sample(instance, &cooked_time, 0, 0, raw_offset, offset, dispersion);
+
+ /* for logging purposes */
+ if (!instance->driver->poll)
+ instance->driver_polled++;
+
+ return 1;
+}
+
+int
+RCL_AddPulse(RCL_Instance instance, struct timespec *pulse_time, double second)
+{
+ double correction, dispersion;
+ struct timespec cooked_time;
+
+ LCL_GetOffsetCorrection(pulse_time, &correction, &dispersion);
+ UTI_AddDoubleToTimespec(pulse_time, correction, &cooked_time);
+ second += correction;
+
+ if (!UTI_IsTimeOffsetSane(pulse_time, 0.0))
+ return 0;
+
+ return RCL_AddCookedPulse(instance, &cooked_time, second, dispersion, correction);
+}
+
+static int
+check_pulse_edge(RCL_Instance instance, double offset, double distance)
+{
+ double max_error;
+
+ if (instance->pulse_width <= 0.0)
+ return 1;
+
+ max_error = 1.0 / instance->pps_rate - instance->pulse_width;
+ max_error = MIN(instance->pulse_width, max_error);
+ max_error *= 0.5;
+
+ if (fabs(offset) > max_error || distance > max_error) {
+ DEBUG_LOG("refclock pulse ignored offset=%.9f distance=%.9f max_error=%.9f",
+ offset, distance, max_error);
+ return 0;
+ }
+
+ return 1;
+}
+
+int
+RCL_AddCookedPulse(RCL_Instance instance, struct timespec *cooked_time,
+ double second, double dispersion, double raw_correction)
+{
+ double offset;
+ int rate;
+ NTP_Leap leap;
+
+ if (!UTI_IsTimeOffsetSane(cooked_time, second) ||
+ !valid_sample_time(instance, cooked_time))
+ return 0;
+
+ leap = LEAP_Normal;
+ dispersion += instance->precision;
+ rate = instance->pps_rate;
+
+ offset = -second + instance->offset;
+
+ /* Adjust the offset to [-0.5/rate, 0.5/rate) interval */
+ offset -= (long)(offset * rate) / (double)rate;
+ if (offset < -0.5 / rate)
+ offset += 1.0 / rate;
+ else if (offset >= 0.5 / rate)
+ offset -= 1.0 / rate;
+
+ if (instance->lock_ref != -1) {
+ RCL_Instance lock_refclock;
+ NTP_Sample ref_sample;
+ double sample_diff, shift;
+
+ lock_refclock = get_refclock(instance->lock_ref);
+
+ if (!SPF_GetLastSample(lock_refclock->filter, &ref_sample)) {
+ if (instance->local) {
+ /* Make the first sample in order to lock to itself */
+ ref_sample.time = *cooked_time;
+ ref_sample.offset = offset;
+ ref_sample.peer_delay = ref_sample.peer_dispersion = 0;
+ ref_sample.root_delay = ref_sample.root_dispersion = 0;
+ } else {
+ DEBUG_LOG("refclock pulse ignored no ref sample");
+ return 0;
+ }
+ }
+
+ ref_sample.root_dispersion += SPF_GetAvgSampleDispersion(lock_refclock->filter);
+
+ sample_diff = UTI_DiffTimespecsToDouble(cooked_time, &ref_sample.time);
+ if (fabs(sample_diff) >= (double)instance->max_lock_age / rate) {
+ DEBUG_LOG("refclock pulse ignored samplediff=%.9f", sample_diff);
+
+ /* Restart the local mode */
+ if (instance->local) {
+ LOG(LOGS_WARN, "Local refclock lost lock");
+ SPF_DropSamples(instance->filter);
+ SRC_ResetInstance(instance->source);
+ }
+ return 0;
+ }
+
+ /* Align the offset to the reference sample */
+ shift = round((ref_sample.offset - offset) * rate) / rate;
+
+ offset += shift;
+
+ if (fabs(ref_sample.offset - offset) +
+ ref_sample.root_dispersion + dispersion > PPS_LOCK_LIMIT / rate) {
+ DEBUG_LOG("refclock pulse ignored offdiff=%.9f refdisp=%.9f disp=%.9f",
+ ref_sample.offset - offset, ref_sample.root_dispersion, dispersion);
+ return 0;
+ }
+
+ if (!check_pulse_edge(instance, ref_sample.offset - offset, 0.0))
+ return 0;
+
+ leap = lock_refclock->leap_status;
+
+ DEBUG_LOG("refclock pulse offset=%.9f offdiff=%.9f samplediff=%.9f",
+ offset, ref_sample.offset - offset, sample_diff);
+ } else {
+ struct timespec ref_time;
+ int is_synchronised, stratum;
+ double root_delay, root_dispersion, distance;
+ uint32_t ref_id;
+
+ /* Ignore the pulse if we are not well synchronized and the local
+ reference is not active */
+
+ REF_GetReferenceParams(cooked_time, &is_synchronised, &leap, &stratum,
+ &ref_id, &ref_time, &root_delay, &root_dispersion);
+ distance = fabs(root_delay) / 2 + root_dispersion;
+
+ if (leap == LEAP_Unsynchronised || distance >= 0.5 / rate) {
+ DEBUG_LOG("refclock pulse ignored offset=%.9f sync=%d dist=%.9f",
+ offset, leap != LEAP_Unsynchronised, distance);
+ /* Drop also all stored samples */
+ SPF_DropSamples(instance->filter);
+ return 0;
+ }
+
+ if (!check_pulse_edge(instance, offset, distance))
+ return 0;
+ }
+
+ if (!accumulate_sample(instance, cooked_time, offset, dispersion))
+ return 0;
+
+ instance->leap_status = leap;
+ instance->pps_active = 1;
+
+ log_sample(instance, cooked_time, 0, 1, offset + raw_correction - instance->offset,
+ offset, dispersion);
+
+ /* for logging purposes */
+ if (!instance->driver->poll)
+ instance->driver_polled++;
+
+ return 1;
+}
+
+double
+RCL_GetPrecision(RCL_Instance instance)
+{
+ return instance->precision;
+}
+
+int
+RCL_GetDriverPoll(RCL_Instance instance)
+{
+ return instance->driver_poll;
+}
+
+static int
+valid_sample_time(RCL_Instance instance, struct timespec *sample_time)
+{
+ struct timespec now;
+ double diff;
+
+ LCL_ReadCookedTime(&now, NULL);
+ diff = UTI_DiffTimespecsToDouble(&now, sample_time);
+
+ if (diff < 0.0 || diff > UTI_Log2ToDouble(instance->poll + 1)) {
+ DEBUG_LOG("%s refclock sample time %s not valid age=%.6f",
+ UTI_RefidToString(instance->ref_id),
+ UTI_TimespecToString(sample_time), diff);
+ return 0;
+ }
+
+ return 1;
+}
+
+static int
+pps_stratum(RCL_Instance instance, struct timespec *ts)
+{
+ struct timespec ref_time;
+ int is_synchronised, stratum;
+ unsigned int i;
+ double root_delay, root_dispersion;
+ NTP_Leap leap;
+ uint32_t ref_id;
+ RCL_Instance refclock;
+
+ REF_GetReferenceParams(ts, &is_synchronised, &leap, &stratum,
+ &ref_id, &ref_time, &root_delay, &root_dispersion);
+
+ /* Don't change our stratum if the local reference is active
+ or this is the current source */
+ if (ref_id == instance->ref_id ||
+ (!is_synchronised && leap != LEAP_Unsynchronised))
+ return stratum - 1;
+
+ /* Or the current source is another PPS refclock */
+ for (i = 0; i < ARR_GetSize(refclocks); i++) {
+ refclock = get_refclock(i);
+ if (refclock->ref_id == ref_id &&
+ refclock->pps_active && refclock->lock_ref == -1)
+ return stratum - 1;
+ }
+
+ return 0;
+}
+
+static void
+get_local_stats(RCL_Instance inst, struct timespec *ref, double *freq, double *offset)
+{
+ double offset_sd, freq_sd, skew, root_delay, root_disp;
+ SST_Stats stats = SRC_GetSourcestats(inst->source);
+
+ if (SST_Samples(stats) < SST_GetMinSamples(stats)) {
+ UTI_ZeroTimespec(ref);
+ return;
+ }
+
+ SST_GetTrackingData(stats, ref, offset, &offset_sd, freq, &freq_sd,
+ &skew, &root_delay, &root_disp);
+}
+
+static void
+follow_local(RCL_Instance inst, struct timespec *prev_ref_time, double prev_freq,
+ double prev_offset)
+{
+ SST_Stats stats = SRC_GetSourcestats(inst->source);
+ double freq, dfreq, offset, doffset, elapsed;
+ struct timespec now, ref_time;
+
+ get_local_stats(inst, &ref_time, &freq, &offset);
+
+ if (UTI_IsZeroTimespec(prev_ref_time) || UTI_IsZeroTimespec(&ref_time))
+ return;
+
+ dfreq = (freq - prev_freq) / (1.0 - prev_freq);
+ elapsed = UTI_DiffTimespecsToDouble(&ref_time, prev_ref_time);
+ doffset = offset - elapsed * prev_freq - prev_offset;
+
+ if (!REF_AdjustReference(doffset, dfreq))
+ return;
+
+ LCL_ReadCookedTime(&now, NULL);
+ SST_SlewSamples(stats, &now, dfreq, doffset);
+ SPF_SlewSamples(inst->filter, &now, dfreq, doffset);
+
+ /* Keep the offset close to zero to not lose precision */
+ if (fabs(offset) >= 1.0) {
+ SST_CorrectOffset(stats, -round(offset));
+ SPF_CorrectOffset(inst->filter, -round(offset));
+ }
+}
+
+static void
+poll_timeout(void *arg)
+{
+ NTP_Sample sample;
+ int poll, stratum;
+
+ RCL_Instance inst = (RCL_Instance)arg;
+
+ poll = inst->poll;
+
+ if (inst->driver->poll) {
+ poll = inst->driver_poll;
+ inst->driver->poll(inst);
+ inst->driver_polled++;
+ }
+
+ if (!(inst->driver->poll && inst->driver_polled < (1 << (inst->poll - inst->driver_poll)))) {
+ inst->driver_polled = 0;
+
+ if (SPF_GetFilteredSample(inst->filter, &sample)) {
+ double local_freq, local_offset;
+ struct timespec local_ref_time;
+
+ /* Handle special case when PPS is used with the local reference */
+ if (inst->pps_active && inst->lock_ref == -1)
+ stratum = pps_stratum(inst, &sample.time);
+ else
+ stratum = inst->stratum;
+
+ if (inst->local) {
+ get_local_stats(inst, &local_ref_time, &local_freq, &local_offset);
+ inst->leap_status = LEAP_Unsynchronised;
+ }
+
+ SRC_UpdateReachability(inst->source, 1);
+ SRC_UpdateStatus(inst->source, stratum, inst->leap_status);
+ SRC_AccumulateSample(inst->source, &sample);
+ SRC_SelectSource(inst->source);
+
+ if (inst->local)
+ follow_local(inst, &local_ref_time, local_freq, local_offset);
+
+ log_sample(inst, &sample.time, 1, 0, 0.0, sample.offset, sample.peer_dispersion);
+ } else {
+ SRC_UpdateReachability(inst->source, 0);
+ }
+ }
+
+ inst->timeout_id = SCH_AddTimeoutByDelay(UTI_Log2ToDouble(poll), poll_timeout, arg);
+}
+
+static void
+slew_samples(struct timespec *raw, struct timespec *cooked, double dfreq,
+ double doffset, LCL_ChangeType change_type, void *anything)
+{
+ unsigned int i;
+
+ for (i = 0; i < ARR_GetSize(refclocks); i++) {
+ if (change_type == LCL_ChangeUnknownStep)
+ SPF_DropSamples(get_refclock(i)->filter);
+ else
+ SPF_SlewSamples(get_refclock(i)->filter, cooked, dfreq, doffset);
+ }
+}
+
+static void
+add_dispersion(double dispersion, void *anything)
+{
+ unsigned int i;
+
+ for (i = 0; i < ARR_GetSize(refclocks); i++)
+ SPF_AddDispersion(get_refclock(i)->filter, dispersion);
+}
+
+static void
+log_sample(RCL_Instance instance, struct timespec *sample_time, int filtered, int pulse, double raw_offset, double cooked_offset, double dispersion)
+{
+ char sync_stats[4] = {'N', '+', '-', '?'};
+
+ if (logfileid == -1)
+ return;
+
+ if (!filtered) {
+ LOG_FileWrite(logfileid, "%s.%06d %-5s %3d %1c %1d %13.6e %13.6e %10.3e",
+ UTI_TimeToLogForm(sample_time->tv_sec),
+ (int)sample_time->tv_nsec / 1000,
+ UTI_RefidToString(instance->ref_id),
+ instance->driver_polled,
+ sync_stats[instance->leap_status],
+ pulse,
+ raw_offset,
+ cooked_offset,
+ dispersion);
+ } else {
+ LOG_FileWrite(logfileid, "%s.%06d %-5s - %1c - - %13.6e %10.3e",
+ UTI_TimeToLogForm(sample_time->tv_sec),
+ (int)sample_time->tv_nsec / 1000,
+ UTI_RefidToString(instance->ref_id),
+ sync_stats[instance->leap_status],
+ cooked_offset,
+ dispersion);
+ }
+}