/* Name of a system timezone containing leap seconds occuring at midnight */
static char *leapsec_tz = NULL;
+/* File name of leap seconds list, usually /usr/share/zoneinfo/leap-seconds.list */
+static char *leapsec_list = NULL;
+
/* Name of the user to which will be dropped root privileges. */
static char *user;
Free(hwclock_file);
Free(keys_file);
Free(leapsec_tz);
+ Free(leapsec_list);
Free(logdir);
Free(bind_ntp_iface);
Free(bind_acq_iface);
parse_leapsecmode(p);
} else if (!strcasecmp(command, "leapsectz")) {
parse_string(p, &leapsec_tz);
+ } else if (!strcasecmp(command, "leapseclist")) {
+ parse_string(p, &leapsec_list);
} else if (!strcasecmp(command, "local")) {
parse_local(p);
} else if (!strcasecmp(command, "lock_all")) {
/* ================================================== */
+char *
+CNF_GetLeapSecList(void)
+{
+ return leapsec_list;
+}
+
+/* ================================================== */
+
int
CNF_GetSchedPriority(void)
{
*tai*:::
This option indicates that the reference clock keeps time in TAI instead of UTC
and that *chronyd* should correct its offset by the current TAI-UTC offset. The
-<<leapsectz,*leapsectz*>> directive must be used with this option and the
-database must be kept up to date in order for this correction to work as
-expected. This option does not make sense with PPS refclocks.
+<<leapsectz,*leapsectz*>> or <<leapseclist,*leapseclist*>> directive must be
+used with this option and the database must be kept up to date in order for
+this correction to work as expected. This option does not make sense with PPS
+refclocks.
*local*:::
This option specifies that the reference clock is an unsynchronised clock which
is more stable than the system clock (e.g. TCXO, OCXO, or atomic clock) and
Wed Dec 31 23:59:60 UTC 2008
----
+[[leapseclist]]*leapseclist* _file_::
+This directive specifies the path to a file containing a list of leap seconds
+and TAI-UTC offsets in NIST/IERS format. It is recommended to use
+the file _leap-seconds.list_ usually included with the system timezone
+database. The behaviour of this directive is otherwise equivalent to
+<<leapsectz,*leapsectz*>>.
++
+An example of this directive is:
++
+----
+leapseclist /usr/share/zoneinfo/leap-seconds.list
+----
+
[[makestep]]*makestep* _threshold_ _limit_::
Normally *chronyd* will cause the system to gradually correct any time offset,
by slowing down or speeding up the clock as required. In certain situations,
**********************************************************************
* Copyright (C) Miroslav Lichvar 2009-2018, 2020, 2022
+ * Copyright (C) Patrick Oppenlander 2023, 2024
*
* 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
#include "conf.h"
#include "leapdb.h"
#include "logging.h"
+#include "util.h"
/* ================================================== */
-/* Name of a system timezone containing leap seconds occuring at midnight */
-static char *leap_tzname;
+/* Source of leap second data */
+enum {
+ SRC_NONE,
+ SRC_TIMEZONE,
+ SRC_LIST,
+} leap_src;
+
+/* Offset between leap-seconds.list timestamp epoch and Unix epoch.
+ leap-seconds.list epoch is 1 Jan 1900, 00:00:00 */
+#define LEAP_SEC_LIST_OFFSET 2208988800
/* ================================================== */
return tz_leap;
strcpy(tz_orig, tz_env);
}
- setenv("TZ", leap_tzname, 1);
+ setenv("TZ", CNF_GetLeapSecTimezone(), 1);
tzset();
/* Get the TAI-UTC offset, which started at the epoch at 10 seconds */
/* ================================================== */
+static NTP_Leap
+get_list_leap(time_t when, int *tai_offset)
+{
+ FILE *f;
+ char line[1024];
+ NTP_Leap ret_leap = LEAP_Normal;
+ int ret_tai_offset = 0, prev_lsl_tai_offset = 10;
+ int64_t lsl_updated = 0, lsl_expiry = 0;
+ const char *leap_sec_list = CNF_GetLeapSecList();
+
+ if (!(f = UTI_OpenFile(NULL, leap_sec_list, NULL, 'r', 0))) {
+ LOG(LOGS_ERR, "Failed to open leap seconds list %s", leap_sec_list);
+ goto out;
+ }
+
+ /* Leap second happens at midnight */
+ when = (when / (24 * 3600) + 1) * (24 * 3600);
+
+ /* leap-seconds.list timestamps are relative to 1 Jan 1900, 00:00:00 */
+ when += LEAP_SEC_LIST_OFFSET;
+
+ while (fgets(line, sizeof line, f) > 0) {
+ int64_t lsl_when;
+ int lsl_tai_offset;
+ char *p;
+
+ /* Ignore blank lines */
+ for (p = line; *p && isspace(*p); ++p)
+ ;
+ if (!*p)
+ continue;
+
+ if (*line == '#') {
+ /* Update time line starts with #$ */
+ if (line[1] == '$' && sscanf(line + 2, "%"SCNd64, &lsl_updated) != 1)
+ goto error;
+ /* Expiration time line starts with #@ */
+ if (line[1] == '@' && sscanf(line + 2, "%"SCNd64, &lsl_expiry) != 1)
+ goto error;
+ /* Comment or a special comment we don't care about */
+ continue;
+ }
+
+ /* Leap entry */
+ if (sscanf(line, "%"SCNd64" %d", &lsl_when, &lsl_tai_offset) != 2)
+ goto error;
+
+ if (when == lsl_when) {
+ if (lsl_tai_offset > prev_lsl_tai_offset)
+ ret_leap = LEAP_InsertSecond;
+ else if (lsl_tai_offset < prev_lsl_tai_offset)
+ ret_leap = LEAP_DeleteSecond;
+ /* When is rounded to the end of the day, so offset hasn't changed yet! */
+ ret_tai_offset = prev_lsl_tai_offset;
+ } else if (when > lsl_when) {
+ ret_tai_offset = lsl_tai_offset;
+ }
+
+ prev_lsl_tai_offset = lsl_tai_offset;
+ }
+
+ /* Make sure the file looks sensible */
+ if (!feof(f) || !lsl_updated || !lsl_expiry)
+ goto error;
+
+ if (when >= lsl_expiry)
+ LOG(LOGS_WARN, "Leap second list %s needs update", leap_sec_list);
+
+ goto out;
+
+error:
+ if (f)
+ fclose(f);
+ LOG(LOGS_ERR, "Failed to parse leap seconds list %s", leap_sec_list);
+ return LEAP_Normal;
+
+out:
+ if (f)
+ fclose(f);
+ *tai_offset = ret_tai_offset;
+ return ret_leap;
+}
+
+/* ================================================== */
+
static int
check_leap_source(NTP_Leap (*src)(time_t when, int *tai_offset))
{
void
LDB_Initialise(void)
{
+ const char *leap_tzname, *leap_sec_list;
+
leap_tzname = CNF_GetLeapSecTimezone();
if (leap_tzname && !check_leap_source(get_tz_leap)) {
LOG(LOGS_WARN, "Timezone %s failed leap second check, ignoring", leap_tzname);
leap_tzname = NULL;
}
- if (leap_tzname)
+ leap_sec_list = CNF_GetLeapSecList();
+ if (leap_sec_list && !check_leap_source(get_list_leap)) {
+ LOG(LOGS_WARN, "Leap second list %s failed check, ignoring", leap_sec_list);
+ leap_sec_list = NULL;
+ }
+
+ if (leap_sec_list) {
+ LOG(LOGS_INFO, "Using leap second list %s", leap_sec_list);
+ leap_src = SRC_LIST;
+ } else if (leap_tzname) {
LOG(LOGS_INFO, "Using %s timezone to obtain leap second data", leap_tzname);
+ leap_src = SRC_TIMEZONE;
+ }
}
/* ================================================== */
ldb_leap = LEAP_Normal;
ldb_tai_offset = 0;
- if (leap_tzname)
+ switch (leap_src) {
+ case SRC_NONE:
+ break;
+ case SRC_TIMEZONE:
ldb_leap = get_tz_leap(when, &ldb_tai_offset);
+ break;
+ case SRC_LIST:
+ ldb_leap = get_list_leap(when, &ldb_tai_offset);
+ break;
+ }
out:
*tai_offset = ldb_tai_offset;
projects / thirdparty / chrony.git / commitdiff
