#include <arpa/inet.h> // ntohl and ntohs
#include <string.h> //strsep
-#include <stdio.h> // snprintf
+#include <stdio.h> // snprintf
#include <stdlib.h> // drand48
#include <unistd.h> // usleep
for (obfc = 0; obfc < buf_len; obfc++) {
snprintf(obfp, 3, "%02X", *tbuf);
obfp += 2;
- tbuf = tbuf+1;
+ tbuf = tbuf + 1;
};
*obfp = 0;
return hexcharbuffer;
}
void handle_control_port_messages(char *buf, ssize_t recv_len,
- clock_source_private_data *clock_private_info, uint64_t reception_time) {
+ clock_source_private_data *clock_private_info,
+ uint64_t reception_time) {
if (recv_len != -1) {
buf[recv_len - 1] = 0; // make sure there's a null in it!
debug(2, "New control port message: \"%s\".", buf);
char *smi_name = strsep(&ip_list, " ");
char *command = NULL;
if (smi_name != NULL) {
- int client_id = 0;
if (ip_list != NULL)
command = strsep(&ip_list, " ");
// "B" is for play begin/resume. Assumes a "T <ip>" already
// "E" is for play end/stop.
// "P" is for pause (currently Buffered Audio only).
- //
+ //
// "T <ip>" is for the IP address of a timer.
// "T" means no active timer.
// clock_is_active is made true by Play and false by Pause or End.
-
+
if ((strcmp(command, "B") == 0) && (ip_list == NULL)) {
- debug(2,"Play.");
+ debug(2, "Play.");
// We want to avoid, as much as possible, resetting the clock smoothing.
// If we know the clock is already active or
// if it's only been a short time since we know it was last active
// then we will not reset the clock.
if (clock_is_active) {
- debug(2,"clock is already active");
+ debug(2, "clock is already active");
} else {
// Find out if the clock is active i.e. not sleeping.
// We know it is active between "B" and "E" commands.
- // We also know it is active for brief periods after the "T" and "E" commands are received.
- // If it is not definitely active, we will reset smoothing.
+ // We also know it is active for brief periods after the "T" and "E" commands are
+ // received. If it is not definitely active, we will reset smoothing.
int will_ask_for_a_reset = 0;
if (clock_validity_expiration_time == 0) {
- debug(1,"no clock_validity_expiration_time.");
+ debug(1, "no clock_validity_expiration_time.");
will_ask_for_a_reset = 1;
} else {
int64_t time_to_clock_expiration = clock_validity_expiration_time - reception_time;
// timings obtained with an iPhone Xs Max on battery save
-
+
// around 30 seconds at a buffered audio pause on an iphone.
// around 1 second after a buffered audio stop on an iphone
// 10 seconds after a "T" from an iPhone that immediately sleeps
// more than a minute from "T" from a HomePod mini.
-
+
if (time_to_clock_expiration < 0) {
- debug(2,"Clock validity may have expired, so ask for a reset.");
+ debug(2, "Clock validity may have expired, so ask for a reset.");
will_ask_for_a_reset = 1;
}
}
if (will_ask_for_a_reset != 0) {
- debug(2,"Reset clock smoothing");
+ debug(2, "Reset clock smoothing");
reset_clock_smoothing = 1;
}
}
clock_is_active = 1;
clock_validity_expiration_time = 0;
} else if ((strcmp(command, "E") == 0) && (ip_list == NULL)) {
- debug(2,"Stop");
+ debug(2, "Stop");
if (clock_is_active) {
- debug(2,"reset clock_validity_expiration_time to 2.25 seconds in the future.");
- clock_validity_expiration_time = reception_time + 2250000000; // expiration time can be very soon after an "E"
+ debug(2, "reset clock_validity_expiration_time to 2.25 seconds in the future.");
+ clock_validity_expiration_time =
+ reception_time + 2250000000; // expiration time can be very soon after an "E"
clock_is_active = 0;
} else {
- debug(2,"clock is already inactive.");
+ debug(2, "clock is already inactive.");
}
} else if ((strcmp(command, "P") == 0) && (ip_list == NULL)) {
- debug(2,"Pause");
- // A pause always seems to turn into a Stop in now more than a few seconds, and the clock keeps going, it seems
- // so there is nothing to do here.
+ debug(2, "Pause");
+ // A pause always seems to turn into a Stop in now more than a few seconds, and the clock
+ // keeps going, it seems so there is nothing to do here.
} else if ((command == NULL) || ((strcmp(command, "T") == 0) && (ip_list == NULL))) {
- debug(2,"Stop Timing");
+ debug(2, "Stop Timing");
clock_is_active = 0;
- debug(2,"Clear timing peer group.");
+ debug(2, "Clear timing peer group.");
// dirty experimental hack -- delete all the clocks
int gc;
for (gc = 0; gc < MAX_CLOCKS; gc++) {
memset(&clock_private_info[gc], 0, sizeof(clock_source_private_data));
- }
-
- // clear all the flags
- debug(2, "Stop monitoring clock.");
- int client_id = get_client_id(smi_name); // create the record if it doesn't exist
- if (client_id != -1) {
- /*
- int i;
- for (i = 0; i < MAX_CLOCKS; i++) {
- // e.g. (obsolete)
- clock_private_info[i].flags &= ~(1 << clock_is_master);
- clock_private_info[i].mastership_start_time = 0;
- clock_private_info[i].previous_offset_time = 0;
-
- // if a clock would now stop being a master everywhere
- // it should drop mastership history and do a sync when it becomes master again
- if ((clock_private_info[i].client_flags[client_id] & (1 << clock_is_master)) !=
- 0) { // if clock[i] is master for this client's timing group
- int c;
- int this_clock_is_master_elsewhere = 0;
- for (c = 0; c < MAX_CLIENTS; c++) {
- if ((c != client_id) &&
- ((clock_private_info[i].client_flags[c] & (1 << clock_is_master)) != 0))
- this_clock_is_master_elsewhere = 1;
- }
- if (this_clock_is_master_elsewhere == 0) {
- clock_private_info[i].mastership_start_time = 0;
- clock_private_info[i].previous_offset_time = 0;
- }
- }
- clock_private_info[i].client_flags[client_id] = 0;
-
- }
- */
- update_master_clock_info(client_id, 0, NULL, 0, 0, 0); // it may have obsolete stuff in it
}
- new_update_master_clock_info(0, NULL, 0, 0, 0); // it may have obsolete stuff in it
+ update_master_clock_info(0, NULL, 0, 0, 0); // the SMI may have obsolete stuff in it
} else {
- debug(2,"Start Timing");
- debug(2,"Clear timing peer group.");
+ debug(2, "Start Timing");
// dirty experimental hack -- delete all the clocks
int gc;
for (gc = 0; gc < MAX_CLOCKS; gc++) {
memset(&clock_private_info[gc], 0, sizeof(clock_source_private_data));
- }
+ }
debug(2, "get or create new record for \"%s\".", smi_name);
- client_id = get_client_id(smi_name); // create the record if it doesn't exist
- if (client_id != -1) {
- if (strcmp(command, "T") == 0) {
- int i;
- for (i = 0; i < MAX_CLOCKS; i++) {
- clock_private_info[i].announcements_without_followups =
- 0; // to allow a possibly silent clock to be revisited when added to a timing
- // peer list
- clock_private_info[i].follow_up_number = 0;
- }
-
- // take the first ip and make it the master, permanently
-
-
- if (ip_list != NULL) {
- char *new_ip = strsep(&ip_list, " ");
- // look for the IP in the list of clocks, and create an inert entry if not there
- if ((new_ip != NULL) && (new_ip[0] != 0)) {
- int t = find_clock_source_record(new_ip, clock_private_info);
- if (t == -1)
- t = create_clock_source_record(new_ip, clock_private_info);
- if (t != -1) { // if the clock table is not full, show it's a timing peer
- debug(2, "Monitor clock at %s.", new_ip);
- clock_private_info[t].client_flags[client_id] |= (1 << clock_is_master);
- }
- // otherwise, drop it
- }
-
-
- }
-
+ // client_id = get_client_id(smi_name); // create the record if it doesn't exist
+ // if (client_id != -1) {
+ if (strcmp(command, "T") == 0) {
+ int i;
+ for (i = 0; i < MAX_CLOCKS; i++) {
+ clock_private_info[i].announcements_without_followups =
+ 0; // to allow a possibly silent clock to be revisited when added to a timing
+ // peer list
+ clock_private_info[i].follow_up_number = 0;
+ }
-/*
- while (ip_list != NULL) {
- char *new_ip = strsep(&ip_list, " ");
- // look for the IP in the list of clocks, and create an inert entry if not there
- if ((new_ip != NULL) && (new_ip[0] != 0)) {
- int t = find_clock_source_record(new_ip, clock_private_info);
- if (t == -1)
- t = create_clock_source_record(new_ip, clock_private_info);
- if (t != -1) { // if the clock table is not full, show it's a timing peer
- clock_private_info[t].client_flags[client_id] |= (1 << clock_is_a_timing_peer);
- }
- // otherwise, drop it
+ // take the first ip and make it the master, permanently
+
+ if (ip_list != NULL) {
+ char *new_ip = strsep(&ip_list, " ");
+ // look for the IP in the list of clocks, and create an inert entry if not there
+ if ((new_ip != NULL) && (new_ip[0] != 0)) {
+ int t = find_clock_source_record(new_ip, clock_private_info);
+ if (t == -1)
+ t = create_clock_source_record(new_ip, clock_private_info);
+ if (t != -1) { // if the clock table is not full, okay
+ debug(2, "Monitor clock at %s.", new_ip);
}
+ // otherwise, drop it
}
-*/
- // a new clock timing record will be started now
- debug(2,"reset clock_validity_expiration_time to 5.0 seconds in the future.");
- clock_validity_expiration_time = reception_time + 5000000000L; // clock can stop as soon as 6 seconds after a "T"
- } else {
- warn("Unrecognised string on the control port.");
}
+ // a new clock timing record will be started now
+ debug(2, "reset clock_validity_expiration_time to 5.0 seconds in the future.");
+ clock_validity_expiration_time =
+ reception_time + 5000000000L; // clock can stop as soon as 6 seconds after a "T"
} else {
- warn("Could not find or create a record for SMI Interface \"%s\".", smi_name);
+ warn("Unrecognised string on the control port.");
}
+ // } else {
+ // warn("Could not find or create a record for SMI Interface \"%s\".", smi_name);
+ // }
}
} else {
warn("SMI Interface Name not found on the control port.");
clock_private_info->grandmasterPriority2 = msg->announce.grandmasterPriority2;
clock_private_info->stepsRemoved = stepsRemoved;
clock_private_info->clock_port_number = sourcePortID;
-
+
if (clock_private_info->wakeup_sent == 0) {
send_awakening_announcement_sequence(
- clock_private_info->clock_id, clock_private_info->ip, clock_private_info->family,
- clock_private_info->grandmasterPriority1,
- clock_private_info->grandmasterPriority2);
+ clock_private_info->clock_id, clock_private_info->ip, clock_private_info->family,
+ clock_private_info->grandmasterPriority1, clock_private_info->grandmasterPriority2);
clock_private_info->wakeup_sent = 1;
}
}
void handle_sync(char *buf, ssize_t recv_len, clock_source_private_data *clock_private_info,
__attribute__((unused)) uint64_t reception_time) {
+ /*
+ // diagnostic -- decide whether to delay the processing of the follow_up to simulate a noisy
+ network if (drand48() < 0.015) {
+ // generate a random delay between 10 and 3500 milliseconds
+ int delay = (int)((3000 - 60) * drand48()) + 60;
+ debug(1,"Delay sync processing by %u milliseconds.", delay);
+ usleep(delay * 1000);
+ reception_time = get_time_now();
+ }
+ */
+
if (clock_private_info->clock_id == 0) {
debug(2, "Sync received before announcement -- discarded.");
} else {
if ((recv_len >= 0) && ((size_t)recv_len >= sizeof(struct ptp_sync_message))) {
- // debug_print_buffer(1, buf, recv_len);
- struct ptp_sync_message *msg = (struct ptp_sync_message *)buf;
+ // debug_print_buffer(1, buf, recv_len);
+ struct ptp_sync_message *msg = (struct ptp_sync_message *)buf;
- // clang-format off
+ // clang-format off
// actually the precision timestamp needs to be corrected by the Follow_Up Correction_Field contents.
// According to IEEE Std 802.1AS-2020, paragraph 11.4.4.2.1:
including any fractional nanoseconds.
*/
- // clang-format on
+ // clang-format on
- int64_t correction_field = ntoh64(msg->header.correctionField);
+ int64_t correction_field = ntoh64(msg->header.correctionField);
- if (correction_field != 0)
- debug(1, "Sync correction field is non-zero: %" PRId64 " ns.", correction_field);
+ if (correction_field != 0)
+ debug(1, "Sync correction field is non-zero: %" PRId64 " ns.", correction_field);
- correction_field = correction_field / 65536; // might be signed
+ correction_field = correction_field / 65536; // might be signed
} else {
debug(1, "Sync message is too small to be valid.");
}
if (clock_private_info->clock_id == 0) {
debug(2, "Follow_Up received before announcement -- discarded.");
} else {
- /*
- // diagnostic -- decide whether to delay the processing of the follow_up to simulate a noisy network
- if (drand48() < 0.05) {
- // generate a random delay between 10 and 3500 milliseconds
- int delay = (int)((3500 - 10) * drand48()) + 10;
- debug(1,"Delay follow_up processing by %u milliseconds.", delay);
- usleep(delay * 1000);
- reception_time = get_time_now();
- }
- */
clock_private_info->announcements_without_followups = 0;
if ((recv_len >= 0) && ((size_t)recv_len >= sizeof(struct ptp_follow_up_message))) {
- // debug_print_buffer(1, buf, recv_len);
- struct ptp_follow_up_message *msg = (struct ptp_follow_up_message *)buf;
- uint16_t seconds_hi = nctohs(&msg->follow_up.preciseOriginTimestamp[0]);
- uint32_t seconds_low = nctohl(&msg->follow_up.preciseOriginTimestamp[2]);
- uint32_t nanoseconds = nctohl(&msg->follow_up.preciseOriginTimestamp[6]);
- uint64_t preciseOriginTimestamp = seconds_hi;
- preciseOriginTimestamp = preciseOriginTimestamp << 32;
- preciseOriginTimestamp = preciseOriginTimestamp + seconds_low;
- preciseOriginTimestamp = preciseOriginTimestamp * 1000000000L;
- preciseOriginTimestamp = preciseOriginTimestamp + nanoseconds;
-
- // update our sample information
- int grandmasterClockIsStopped = 0;
- if ((clock_private_info->previous_preciseOriginTimestamp == preciseOriginTimestamp) && (clock_private_info->clock_id == clock_private_info->grandmasterIdentity)) {
- clock_private_info->identical_previous_preciseOriginTimestamp_count++;
- grandmasterClockIsStopped = 1;
- if (clock_private_info->identical_previous_preciseOriginTimestamp_count == 8 * 60) {
- int64_t duration_of_mastership =
- reception_time - clock_private_info->mastership_start_time;
- if (clock_private_info->mastership_start_time == 0)
- duration_of_mastership = 0;
+ // debug_print_buffer(1, buf, recv_len);
+ struct ptp_follow_up_message *msg = (struct ptp_follow_up_message *)buf;
+ uint16_t seconds_hi = nctohs(&msg->follow_up.preciseOriginTimestamp[0]);
+ uint32_t seconds_low = nctohl(&msg->follow_up.preciseOriginTimestamp[2]);
+ uint32_t nanoseconds = nctohl(&msg->follow_up.preciseOriginTimestamp[6]);
+ uint64_t preciseOriginTimestamp = seconds_hi;
+ preciseOriginTimestamp = preciseOriginTimestamp << 32;
+ preciseOriginTimestamp = preciseOriginTimestamp + seconds_low;
+ preciseOriginTimestamp = preciseOriginTimestamp * 1000000000L;
+ preciseOriginTimestamp = preciseOriginTimestamp + nanoseconds;
+
+ // update our sample information
+ int grandmasterClockIsStopped = 0;
+ if ((clock_private_info->previous_preciseOriginTimestamp == preciseOriginTimestamp) &&
+ (clock_private_info->clock_id == clock_private_info->grandmasterIdentity)) {
+ clock_private_info->identical_previous_preciseOriginTimestamp_count++;
+ grandmasterClockIsStopped = 1;
+ if (clock_private_info->identical_previous_preciseOriginTimestamp_count == 8 * 60) {
+ int64_t duration_of_mastership =
+ reception_time - clock_private_info->mastership_start_time;
+ if (clock_private_info->mastership_start_time == 0)
+ duration_of_mastership = 0;
+ debug(2,
+ "Clock %" PRIx64 "'s grandmaster clock has stopped after %f seconds of mastership.",
+ clock_private_info->clock_id, 0.000000001 * duration_of_mastership);
+ int64_t wait_limit = 62;
+ wait_limit = wait_limit * 1000000000;
+ // only try to restart a grandmaster clock on the clock itself.
+ if ((duration_of_mastership <= wait_limit) &&
+ (clock_private_info->clock_id == clock_private_info->grandmasterIdentity)) {
debug(2,
- "Clock %" PRIx64
- "'s grandmaster clock has stopped after %f seconds of mastership.",
- clock_private_info->clock_id, 0.000000001 * duration_of_mastership);
- int64_t wait_limit = 62;
- wait_limit = wait_limit * 1000000000;
- // only try to restart a grandmaster clock on the clock itself.
- if ((duration_of_mastership <= wait_limit) && (clock_private_info->clock_id == clock_private_info->grandmasterIdentity)) {
- debug(2,
- "Attempt to start a stopped clock %" PRIx64
- ", at follow_up_number %u at IP %s.",
- clock_private_info->clock_id, clock_private_info->follow_up_number,
- clock_private_info->ip);
- send_awakening_announcement_sequence(
- clock_private_info->clock_id, clock_private_info->ip, clock_private_info->family,
- clock_private_info->grandmasterPriority1,
- clock_private_info->grandmasterPriority2);
- }
+ "Attempt to start a stopped clock %" PRIx64 ", at follow_up_number %u at IP %s.",
+ clock_private_info->clock_id, clock_private_info->follow_up_number,
+ clock_private_info->ip);
+ send_awakening_announcement_sequence(
+ clock_private_info->clock_id, clock_private_info->ip, clock_private_info->family,
+ clock_private_info->grandmasterPriority1, clock_private_info->grandmasterPriority2);
}
- } else {
- clock_private_info->identical_previous_preciseOriginTimestamp_count = 0;
}
+ } else {
+ clock_private_info->identical_previous_preciseOriginTimestamp_count = 0;
+ }
- clock_private_info->previous_preciseOriginTimestamp = preciseOriginTimestamp;
+ clock_private_info->previous_preciseOriginTimestamp = preciseOriginTimestamp;
- // clang-format off
+ // clang-format off
// actually the precision timestamp needs to be corrected by the Follow_Up Correction_Field contents.
// According to IEEE Std 802.1AS-2020, paragraph 11.4.4.2.1:
including any fractional nanoseconds.
*/
- // clang-format on
+ // clang-format on
- int64_t correction_field = ntoh64(msg->header.correctionField);
+ int64_t correction_field = ntoh64(msg->header.correctionField);
- // debug(1," Check ntoh64: in: %" PRIx64 ", out: %" PRIx64 ".", msg->header.correctionField,
- // correction_field);
+ // debug(1," Check ntoh64: in: %" PRIx64 ", out: %" PRIx64 ".", msg->header.correctionField,
+ // correction_field);
- correction_field = correction_field / 65536; // might be signed
- uint64_t correctedPreciseOriginTimestamp = preciseOriginTimestamp + correction_field;
+ correction_field = correction_field / 65536; // might be signed
+ uint64_t correctedPreciseOriginTimestamp = preciseOriginTimestamp + correction_field;
- if (clock_private_info->follow_up_number < 100)
- clock_private_info->follow_up_number++;
+ if (clock_private_info->follow_up_number < 100)
+ clock_private_info->follow_up_number++;
- // if (clock_private_info->announcements_without_followups < 4) // if we haven't signalled
- // already
- clock_private_info->announcements_without_followups = 0; // we've seen a followup
+ // if (clock_private_info->announcements_without_followups < 4) // if we haven't signalled
+ // already
+ clock_private_info->announcements_without_followups = 0; // we've seen a followup
- debug(2, "FOLLOWUP from %" PRIx64 ", %s.", clock_private_info->clock_id,
- &clock_private_info->ip);
- uint64_t offset = correctedPreciseOriginTimestamp - reception_time;
+ debug(2, "FOLLOWUP from %" PRIx64 ", %s.", clock_private_info->clock_id,
+ &clock_private_info->ip);
+ uint64_t offset = correctedPreciseOriginTimestamp - reception_time;
- int64_t jitter = 0;
+ int64_t jitter = 0;
- int64_t time_since_previous_offset = 0;
- uint64_t smoothed_offset = offset;
+ int64_t time_since_previous_offset = 0;
+ uint64_t smoothed_offset = offset;
- // This is a bit hacky.
- // Basically, the idea is that if the grandmaster has changed, then acceptance checking and
- // smoothing should start as it it's a new clock. This is because the
- // correctedPreciseOriginTimestamp, which is part of the data that is being smoothed, refers
- // to the grandmaster, so when the grandmaster changes any previous calculations are no
- // longer valid. The hacky bit is to signal this condition by zeroing the
- // previous_offset_time.
- if (clock_private_info->previous_offset_grandmaster !=
- clock_private_info->grandmasterIdentity) {
- clock_private_info->previous_offset_time = 0;
- debug(1,"grandmaster has changed from %" PRIx64 " to %" PRIx64 ".", clock_private_info->previous_offset_grandmaster, clock_private_info->grandmasterIdentity);
- }
+ // This is a bit hacky.
+ // Basically, the idea is that if the grandmaster has changed, then acceptance checking and
+ // smoothing should start as it it's a new clock. This is because the
+ // correctedPreciseOriginTimestamp, which is part of the data that is being smoothed, refers
+ // to the grandmaster, so when the grandmaster changes any previous calculations are no
+ // longer valid. The hacky bit is to signal this condition by zeroing the
+ // previous_offset_time.
+ if (clock_private_info->previous_offset_grandmaster !=
+ clock_private_info->grandmasterIdentity) {
+ clock_private_info->previous_offset_time = 0;
+ if (clock_private_info->previous_offset_grandmaster == 0)
+ debug(1, "grandmaster is %" PRIx64 ".", clock_private_info->grandmasterIdentity);
+ else
+ debug(1, "grandmaster has changed from %" PRIx64 " to %" PRIx64 ".",
+ clock_private_info->previous_offset_grandmaster,
+ clock_private_info->grandmasterIdentity);
+ }
- // Do acceptance checking and smoothing.
-
- // Positive changes in the offset are much more likely to be
- // legitimate, since they could only occur due to a shorter
- // propagation time or less of a delay sending or receiving the packet.
- // (Actually, this is not quite true --
- // it is possible that the remote clock could be adjusted forward
- // and this would increase the offset too.)
- // Anyway, when the clock is new, we give extra preferential weighting to
- // positive changes in the offset.
-
- // If the new offset is greater, by any amount, than the old offset,
- // or if it is less by up to 10 mS, accept it.
- // Otherwise, drop it if the last sample was fairly recent
- // If the last sample was long ago, take this as a discontinuity and
- // accept it as the start of a new period of mastership.
-
- // This seems to be quite stable
-
- //if (grandmasterClockIsStopped == 0) {
- if (reset_clock_smoothing == 0) {
-
- if (clock_private_info->previous_offset_time != 0) {
- time_since_previous_offset = reception_time - clock_private_info->previous_offset_time;
- jitter = offset - clock_private_info->previous_offset;
- }
+ // Do acceptance checking and smoothing.
- // We take any positive or a limited negative jitter as a sync event in
- // a continuous synchronisation sequence.
- // This works well with PTP sources that sleep, as when they sleep
- // their clock stops. When they awaken, the offset from
- // the local clock to them must be smaller than before, triggering the
- // timing discontinuity below and allowing an immediate readjustment.
-
- // The full value of a positive offset jitter is accepted for a
- // number of follow_ups at the start.
- // After that, the weight of the jitter is reduced.
- // Follow-ups don't always come in at 125 ms intervals, especially after a discontinuity
- // Delays makes the offsets smaller than they should be, which is quickly
- // allowed for.
-
- const int64_t clamping_limit = -2500000; // nanoseconds
-
- int64_t mastership_time = reception_time - clock_private_info->mastership_start_time;
- if (clock_private_info->mastership_start_time == 0)
- mastership_time = 0;
-
-// if ((clock_private_info->previous_offset_time != 0) && (clock_private_info->identical_previous_preciseOriginTimestamp_count <= 1)) {
- if (clock_private_info->previous_offset_time != 0) {
- if (jitter < 0) {
- int64_t clamped_jitter = jitter;
- if (clamped_jitter < clamping_limit) {
- clamped_jitter = clamping_limit; // 0 means ignore a clamped value completely
- }
- // if (mastership_time < 1000000000) // at the beginning, if jitter is negative
- // smoothed_offset = clock_private_info->previous_offset + clamped_jitter / 16;
- // else
-
- // ignore negative jitter for the first 10 seconds
- if (mastership_time > 1000000000)
- smoothed_offset = clock_private_info->previous_offset + clamped_jitter / 64; // later, if jitter is negative
- } else if (mastership_time < 1000000000) { // at the beginning
- smoothed_offset =
- clock_private_info->previous_offset + jitter / 1; // at the beginning, if jitter is positive -- accept positive changes quickly
- } else {
- smoothed_offset = clock_private_info->previous_offset + jitter / 64; // later, if jitter is positive
- }
- } else {
- if (clock_private_info->previous_offset_time == 0)
- debug(2, "Clock %" PRIx64 " record (re)starting at %s.", clock_private_info->clock_id,
- clock_private_info->ip);
- else
- debug(2,
- "Timing discontinuity on clock %" PRIx64
- " at %s: time_since_previous_offset: %.3f seconds%s.",
- clock_private_info->clock_id, clock_private_info->ip,
- 0.000000001 * time_since_previous_offset,
- grandmasterClockIsStopped != 0 ? ", grandmaster clock stopped" : ""
- );
- smoothed_offset = offset;
- // clock_private_info->follow_up_number = 0;
- clock_private_info->mastership_start_time =
- reception_time; // mastership is reset to this time...
- }
+ // Positive changes in the offset are much more likely to be
+ // legitimate, since they could only occur due to a shorter
+ // propagation time or less of a delay sending or receiving the packet.
+ // (Actually, this is not quite true --
+ // it is possible that the remote clock could be adjusted forward
+ // and this would increase the offset too.)
+ // Anyway, when the clock is new, we give extra preferential weighting to
+ // positive changes in the offset.
- int temp_client_id;
- for (temp_client_id = 0; temp_client_id < MAX_CLIENTS; temp_client_id++) {
- if ((clock_private_info->client_flags[temp_client_id] & (1 << clock_is_master)) != 0) {
- // recalculate mastership_time because it might have been zeroed.
- mastership_time = reception_time - clock_private_info->mastership_start_time;
- if (clock_private_info->mastership_start_time == 0)
- mastership_time = 0;
- if (mastership_time > 200000000) {
- int64_t delta = smoothed_offset - offset;
- debug(2,
- "Clock %" PRIx64 ", grandmaster %" PRIx64 ". Offset: %" PRIx64
- ", smoothed offset: %" PRIx64 ". Smoothed Offset - Offset: %10.3f. Raw Precise Origin Timestamp: %" PRIx64
- ". Time since previous offset: %8.3f milliseconds. ID: %5u, Follow_Up Number: "
- "%u. Source: %s",
- clock_private_info->clock_id, clock_private_info->grandmasterIdentity, offset,
- smoothed_offset, 0.000001 * delta, preciseOriginTimestamp, 0.000001 * time_since_previous_offset,
- ntohs(msg->header.sequenceId), clock_private_info->follow_up_number,
- clock_private_info->ip);
-
- debug(2, "clock_is_master -- updating master clock info for client \"%s\"",
- get_client_name(temp_client_id));
- update_master_clock_info(temp_client_id, clock_private_info->grandmasterIdentity,
- (const char *)&clock_private_info->ip, reception_time,
- smoothed_offset, clock_private_info->mastership_start_time);
- }
+ // If the new offset is greater, by any amount, than the old offset,
+ // or if it is less by up to 10 mS, accept it.
+ // Otherwise, drop it if the last sample was fairly recent
+ // If the last sample was long ago, take this as a discontinuity and
+ // accept it as the start of a new period of mastership.
+
+ // This seems to be quite stable
+
+ // if (grandmasterClockIsStopped == 0) {
+ if (reset_clock_smoothing == 0) {
+
+ if (clock_private_info->previous_offset_time != 0) {
+ time_since_previous_offset = reception_time - clock_private_info->previous_offset_time;
+ jitter = offset - clock_private_info->previous_offset;
+ }
+
+ // We take any positive or a limited negative jitter as a sync event in
+ // a continuous synchronisation sequence.
+
+ // The full value of a positive offset jitter is accepted for a
+ // number of follow_ups at the start.
+ // After that, the weight of the jitter is reduced.
+ // Follow-ups don't always come in at 125 ms intervals, especially after a discontinuity
+ // Delays makes the offsets smaller than they should be, which is quickly
+ // allowed for.
+
+ const int64_t clamping_limit = -2500000; // nanoseconds
+
+ int64_t mastership_time = reception_time - clock_private_info->mastership_start_time;
+ if (clock_private_info->mastership_start_time == 0)
+ mastership_time = 0;
+
+ // if ((clock_private_info->previous_offset_time != 0) &&
+ // (clock_private_info->identical_previous_preciseOriginTimestamp_count <= 1)) {
+ if (clock_private_info->previous_offset_time != 0) {
+ if (jitter < 0) {
+ int64_t clamped_jitter = jitter;
+ if (clamped_jitter < clamping_limit) {
+ clamped_jitter = clamping_limit; // 0 means ignore a clamped value completely
}
+ // if (mastership_time < 1000000000) // at the beginning, if jitter is negative
+ // smoothed_offset = clock_private_info->previous_offset + clamped_jitter / 16;
+ // else
+
+ // ignore negative jitter for the first 10 seconds
+ if (mastership_time > 1000000000)
+ smoothed_offset = clock_private_info->previous_offset +
+ clamped_jitter / 64; // later, if jitter is negative
+ } else if (mastership_time < 1000000000) { // at the beginning
+ smoothed_offset =
+ clock_private_info->previous_offset +
+ jitter /
+ 1; // at the beginning, if jitter is positive -- accept positive changes quickly
+ } else {
+ smoothed_offset =
+ clock_private_info->previous_offset + jitter / 64; // later, if jitter is positive
}
+ } else {
+ if (clock_private_info->previous_offset_time == 0)
+ debug(2, "Clock %" PRIx64 " record (re)starting at %s.", clock_private_info->clock_id,
+ clock_private_info->ip);
+ else
+ debug(2,
+ "Timing discontinuity on clock %" PRIx64
+ " at %s: time_since_previous_offset: %.3f seconds%s.",
+ clock_private_info->clock_id, clock_private_info->ip,
+ 0.000000001 * time_since_previous_offset,
+ grandmasterClockIsStopped != 0 ? ", grandmaster clock stopped" : "");
+ smoothed_offset = offset;
+ // clock_private_info->follow_up_number = 0;
+ clock_private_info->mastership_start_time =
+ reception_time; // mastership is reset to this time...
+ }
- int64_t delta = smoothed_offset - offset;
- debug(2,
- "Clock %" PRIx64 ", grandmaster %" PRIx64 ". Offset: %" PRIx64
- ", smoothed offset: %" PRIx64 ". Smoothed Offset - Offset: %10.3f. Raw Precise Origin Timestamp: %" PRIx64
- "%s correction_field: %" PRIx64
- ". Time since previous offset: %8.3f milliseconds. ID: %5u, Follow_Up Number: "
- "%u. Source: %s",
- clock_private_info->clock_id, clock_private_info->grandmasterIdentity, offset,
- smoothed_offset, 0.000001 * delta, preciseOriginTimestamp,
- grandmasterClockIsStopped == 0 ? ". " : "*.",
- correction_field,
- 0.000001 * time_since_previous_offset,
- ntohs(msg->header.sequenceId), clock_private_info->follow_up_number,
- clock_private_info->ip);
-
- new_update_master_clock_info(clock_private_info->grandmasterIdentity,
- (const char *)&clock_private_info->ip, reception_time,
- smoothed_offset, clock_private_info->mastership_start_time);
-
- clock_private_info->previous_offset = smoothed_offset;
- clock_private_info->previous_offset_time = reception_time;
-
+ int64_t delta = smoothed_offset - offset;
+ debug(2,
+ "Clock %" PRIx64 ", grandmaster %" PRIx64 ". Offset: %" PRIx64
+ ", smoothed offset: %" PRIx64
+ ". Smoothed Offset - Offset: %10.3f. Raw Precise Origin Timestamp: %" PRIx64
+ "%s correction_field: %" PRIx64
+ ". Time since previous offset: %8.3f milliseconds. ID: %5u, Follow_Up Number: "
+ "%u. Source: %s",
+ clock_private_info->clock_id, clock_private_info->grandmasterIdentity, offset,
+ smoothed_offset, 0.000001 * delta, preciseOriginTimestamp,
+ grandmasterClockIsStopped == 0 ? ". " : "*.", correction_field,
+ 0.000001 * time_since_previous_offset, ntohs(msg->header.sequenceId),
+ clock_private_info->follow_up_number, clock_private_info->ip);
+ if (clock_is_active) {
+ update_master_clock_info(clock_private_info->grandmasterIdentity,
+ (const char *)&clock_private_info->ip, reception_time,
+ smoothed_offset, clock_private_info->mastership_start_time);
} else {
- reset_clock_smoothing = 0;
- clock_private_info->mastership_start_time = 0;
- clock_private_info->previous_offset = 0;
- clock_private_info->previous_offset_time = 0; // so that the first non-stopped sample will be taken as the first one in a sequence
+ update_master_clock_info(0, NULL, 0, 0, 0); // the SMI may have obsolete stuff in it
}
- clock_private_info->previous_offset_grandmaster = clock_private_info->grandmasterIdentity;
-
- // now do some quick calculations on the possible "Universal Time"
- // debug_print_buffer(1, "", buf, recv_len);
- uint8_t *tlv = (uint8_t *)&msg->follow_up.tlvs[0];
- uint8_t *lastGmPhaseChange = tlv + 16;
- uint64_t lpt = nctoh64(lastGmPhaseChange + 4);
- uint64_t last_tlv_clock = nctoh64((uint8_t *)buf + 86);
- uint64_t huh = offset - lpt;
- debug_print_buffer(2, buf, (size_t) recv_len);
- debug(2, "%" PRIx64 ", %" PRIx64 ", %s, Origin: %016" PRIx64 ", LPT: %016" PRIx64 ", Offset: %016" PRIx64 ", Universal Offset: %016" PRIx64 ", packet length: %u.", clock_private_info->clock_id, last_tlv_clock, hex_string(lastGmPhaseChange,12), preciseOriginTimestamp, lpt, offset, huh, recv_len);
- // debug(1,"Clock: %" PRIx64 ", UT: %016" PRIx64 ", correctedPOT: %016" PRIx64 ", part of lastGMPhaseChange: %016" PRIx64 ".", packet_clock_id, correctedPOT - lpt, correctedPOT, lpt);
+ clock_private_info->previous_offset = smoothed_offset;
+ clock_private_info->previous_offset_time = reception_time;
+
+ } else {
+ reset_clock_smoothing = 0;
+ clock_private_info->mastership_start_time = 0;
+ clock_private_info->previous_offset = 0;
+ clock_private_info->previous_offset_time =
+ 0; // so that the first non-stopped sample will be taken as the first one in a sequence
+ }
+
+ clock_private_info->previous_offset_grandmaster = clock_private_info->grandmasterIdentity;
+
+ // now do some quick calculations on the possible "Universal Time"
+ // debug_print_buffer(1, "", buf, recv_len);
+ uint8_t *tlv = (uint8_t *)&msg->follow_up.tlvs[0];
+ uint8_t *lastGmPhaseChange = tlv + 16;
+ uint64_t lpt = nctoh64(lastGmPhaseChange + 4);
+ uint64_t last_tlv_clock = nctoh64((uint8_t *)buf + 86);
+ uint64_t huh = offset - lpt;
+ debug_print_buffer(2, buf, (size_t)recv_len);
+ debug(2,
+ "%" PRIx64 ", %" PRIx64 ", %s, Origin: %016" PRIx64 ", LPT: %016" PRIx64
+ ", Offset: %016" PRIx64 ", Universal Offset: %016" PRIx64 ", packet length: %u.",
+ clock_private_info->clock_id, last_tlv_clock, hex_string(lastGmPhaseChange, 12),
+ preciseOriginTimestamp, lpt, offset, huh, recv_len);
+ // debug(1,"Clock: %" PRIx64 ", UT: %016" PRIx64 ", correctedPOT: %016" PRIx64 ", part of
+ // lastGMPhaseChange: %016" PRIx64 ".", packet_clock_id, correctedPOT - lpt, correctedPOT,
+ // lpt);
} else {
debug(1, "Follow_Up message is too small to be valid.");
projects / thirdparty / nqptp.git / commitdiff
