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-rw-r--r--src/basic/time-util.c1773
1 files changed, 1773 insertions, 0 deletions
diff --git a/src/basic/time-util.c b/src/basic/time-util.c
new file mode 100644
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--- /dev/null
+++ b/src/basic/time-util.c
@@ -0,0 +1,1773 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+
+#include <ctype.h>
+#include <errno.h>
+#include <limits.h>
+#include <stdlib.h>
+#include <sys/mman.h>
+#include <sys/time.h>
+#include <sys/timerfd.h>
+#include <sys/types.h>
+#include <unistd.h>
+
+#include "alloc-util.h"
+#include "fd-util.h"
+#include "fileio.h"
+#include "fs-util.h"
+#include "io-util.h"
+#include "log.h"
+#include "macro.h"
+#include "missing_threads.h"
+#include "missing_timerfd.h"
+#include "parse-util.h"
+#include "path-util.h"
+#include "process-util.h"
+#include "stat-util.h"
+#include "string-table.h"
+#include "string-util.h"
+#include "strv.h"
+#include "time-util.h"
+
+static clockid_t map_clock_id(clockid_t c) {
+
+ /* Some more exotic archs (s390, ppc, …) lack the "ALARM" flavour of the clocks. Thus,
+ * clock_gettime() will fail for them. Since they are essentially the same as their non-ALARM
+ * pendants (their only difference is when timers are set on them), let's just map them
+ * accordingly. This way, we can get the correct time even on those archs. */
+
+ switch (c) {
+
+ case CLOCK_BOOTTIME_ALARM:
+ return CLOCK_BOOTTIME;
+
+ case CLOCK_REALTIME_ALARM:
+ return CLOCK_REALTIME;
+
+ default:
+ return c;
+ }
+}
+
+usec_t now(clockid_t clock_id) {
+ struct timespec ts;
+
+ assert_se(clock_gettime(map_clock_id(clock_id), &ts) == 0);
+
+ return timespec_load(&ts);
+}
+
+nsec_t now_nsec(clockid_t clock_id) {
+ struct timespec ts;
+
+ assert_se(clock_gettime(map_clock_id(clock_id), &ts) == 0);
+
+ return timespec_load_nsec(&ts);
+}
+
+dual_timestamp* dual_timestamp_now(dual_timestamp *ts) {
+ assert(ts);
+
+ ts->realtime = now(CLOCK_REALTIME);
+ ts->monotonic = now(CLOCK_MONOTONIC);
+
+ return ts;
+}
+
+triple_timestamp* triple_timestamp_now(triple_timestamp *ts) {
+ assert(ts);
+
+ ts->realtime = now(CLOCK_REALTIME);
+ ts->monotonic = now(CLOCK_MONOTONIC);
+ ts->boottime = now(CLOCK_BOOTTIME);
+
+ return ts;
+}
+
+static usec_t map_clock_usec_internal(usec_t from, usec_t from_base, usec_t to_base) {
+
+ /* Maps the time 'from' between two clocks, based on a common reference point where the first clock
+ * is at 'from_base' and the second clock at 'to_base'. Basically calculates:
+ *
+ * from - from_base + to_base
+ *
+ * But takes care of overflows/underflows and avoids signed operations. */
+
+ if (from >= from_base) { /* In the future */
+ usec_t delta = from - from_base;
+
+ if (to_base >= USEC_INFINITY - delta) /* overflow? */
+ return USEC_INFINITY;
+
+ return to_base + delta;
+
+ } else { /* In the past */
+ usec_t delta = from_base - from;
+
+ if (to_base <= delta) /* underflow? */
+ return 0;
+
+ return to_base - delta;
+ }
+}
+
+usec_t map_clock_usec(usec_t from, clockid_t from_clock, clockid_t to_clock) {
+
+ /* Try to avoid any inaccuracy needlessly added in case we convert from effectively the same clock
+ * onto itself */
+ if (map_clock_id(from_clock) == map_clock_id(to_clock))
+ return from;
+
+ /* Keep infinity as is */
+ if (from == USEC_INFINITY)
+ return from;
+
+ return map_clock_usec_internal(from, now(from_clock), now(to_clock));
+}
+
+dual_timestamp* dual_timestamp_from_realtime(dual_timestamp *ts, usec_t u) {
+ assert(ts);
+
+ if (!timestamp_is_set(u)) {
+ ts->realtime = ts->monotonic = u;
+ return ts;
+ }
+
+ ts->realtime = u;
+ ts->monotonic = map_clock_usec(u, CLOCK_REALTIME, CLOCK_MONOTONIC);
+ return ts;
+}
+
+triple_timestamp* triple_timestamp_from_realtime(triple_timestamp *ts, usec_t u) {
+ usec_t nowr;
+
+ assert(ts);
+
+ if (!timestamp_is_set(u)) {
+ ts->realtime = ts->monotonic = ts->boottime = u;
+ return ts;
+ }
+
+ nowr = now(CLOCK_REALTIME);
+
+ ts->realtime = u;
+ ts->monotonic = map_clock_usec_internal(u, nowr, now(CLOCK_MONOTONIC));
+ ts->boottime = map_clock_usec_internal(u, nowr, now(CLOCK_BOOTTIME));
+
+ return ts;
+}
+
+triple_timestamp* triple_timestamp_from_boottime(triple_timestamp *ts, usec_t u) {
+ usec_t nowb;
+
+ assert(ts);
+
+ if (u == USEC_INFINITY) {
+ ts->realtime = ts->monotonic = ts->boottime = u;
+ return ts;
+ }
+
+ nowb = now(CLOCK_BOOTTIME);
+
+ ts->boottime = u;
+ ts->monotonic = map_clock_usec_internal(u, nowb, now(CLOCK_MONOTONIC));
+ ts->realtime = map_clock_usec_internal(u, nowb, now(CLOCK_REALTIME));
+
+ return ts;
+}
+
+dual_timestamp* dual_timestamp_from_monotonic(dual_timestamp *ts, usec_t u) {
+ assert(ts);
+
+ if (u == USEC_INFINITY) {
+ ts->realtime = ts->monotonic = USEC_INFINITY;
+ return ts;
+ }
+
+ ts->monotonic = u;
+ ts->realtime = map_clock_usec(u, CLOCK_MONOTONIC, CLOCK_REALTIME);
+ return ts;
+}
+
+dual_timestamp* dual_timestamp_from_boottime(dual_timestamp *ts, usec_t u) {
+ usec_t nowm;
+
+ assert(ts);
+
+ if (u == USEC_INFINITY) {
+ ts->realtime = ts->monotonic = USEC_INFINITY;
+ return ts;
+ }
+
+ nowm = now(CLOCK_BOOTTIME);
+ ts->monotonic = map_clock_usec_internal(u, nowm, now(CLOCK_MONOTONIC));
+ ts->realtime = map_clock_usec_internal(u, nowm, now(CLOCK_REALTIME));
+ return ts;
+}
+
+usec_t triple_timestamp_by_clock(triple_timestamp *ts, clockid_t clock) {
+ assert(ts);
+
+ switch (clock) {
+
+ case CLOCK_REALTIME:
+ case CLOCK_REALTIME_ALARM:
+ return ts->realtime;
+
+ case CLOCK_MONOTONIC:
+ return ts->monotonic;
+
+ case CLOCK_BOOTTIME:
+ case CLOCK_BOOTTIME_ALARM:
+ return ts->boottime;
+
+ default:
+ return USEC_INFINITY;
+ }
+}
+
+usec_t timespec_load(const struct timespec *ts) {
+ assert(ts);
+
+ if (ts->tv_sec < 0 || ts->tv_nsec < 0)
+ return USEC_INFINITY;
+
+ if ((usec_t) ts->tv_sec > (UINT64_MAX - (ts->tv_nsec / NSEC_PER_USEC)) / USEC_PER_SEC)
+ return USEC_INFINITY;
+
+ return
+ (usec_t) ts->tv_sec * USEC_PER_SEC +
+ (usec_t) ts->tv_nsec / NSEC_PER_USEC;
+}
+
+nsec_t timespec_load_nsec(const struct timespec *ts) {
+ assert(ts);
+
+ if (ts->tv_sec < 0 || ts->tv_nsec < 0)
+ return NSEC_INFINITY;
+
+ if ((nsec_t) ts->tv_sec >= (UINT64_MAX - ts->tv_nsec) / NSEC_PER_SEC)
+ return NSEC_INFINITY;
+
+ return (nsec_t) ts->tv_sec * NSEC_PER_SEC + (nsec_t) ts->tv_nsec;
+}
+
+struct timespec *timespec_store(struct timespec *ts, usec_t u) {
+ assert(ts);
+
+ if (u == USEC_INFINITY ||
+ u / USEC_PER_SEC >= TIME_T_MAX) {
+ ts->tv_sec = (time_t) -1;
+ ts->tv_nsec = -1L;
+ return ts;
+ }
+
+ ts->tv_sec = (time_t) (u / USEC_PER_SEC);
+ ts->tv_nsec = (long) ((u % USEC_PER_SEC) * NSEC_PER_USEC);
+
+ return ts;
+}
+
+struct timespec *timespec_store_nsec(struct timespec *ts, nsec_t n) {
+ assert(ts);
+
+ if (n == NSEC_INFINITY ||
+ n / NSEC_PER_SEC >= TIME_T_MAX) {
+ ts->tv_sec = (time_t) -1;
+ ts->tv_nsec = -1L;
+ return ts;
+ }
+
+ ts->tv_sec = (time_t) (n / NSEC_PER_SEC);
+ ts->tv_nsec = (long) (n % NSEC_PER_SEC);
+
+ return ts;
+}
+
+usec_t timeval_load(const struct timeval *tv) {
+ assert(tv);
+
+ if (tv->tv_sec < 0 || tv->tv_usec < 0)
+ return USEC_INFINITY;
+
+ if ((usec_t) tv->tv_sec > (UINT64_MAX - tv->tv_usec) / USEC_PER_SEC)
+ return USEC_INFINITY;
+
+ return
+ (usec_t) tv->tv_sec * USEC_PER_SEC +
+ (usec_t) tv->tv_usec;
+}
+
+struct timeval *timeval_store(struct timeval *tv, usec_t u) {
+ assert(tv);
+
+ if (u == USEC_INFINITY ||
+ u / USEC_PER_SEC > TIME_T_MAX) {
+ tv->tv_sec = (time_t) -1;
+ tv->tv_usec = (suseconds_t) -1;
+ } else {
+ tv->tv_sec = (time_t) (u / USEC_PER_SEC);
+ tv->tv_usec = (suseconds_t) (u % USEC_PER_SEC);
+ }
+
+ return tv;
+}
+
+char *format_timestamp_style(
+ char *buf,
+ size_t l,
+ usec_t t,
+ TimestampStyle style) {
+
+ /* The weekdays in non-localized (English) form. We use this instead of the localized form, so that
+ * our generated timestamps may be parsed with parse_timestamp(), and always read the same. */
+ static const char * const weekdays[] = {
+ [0] = "Sun",
+ [1] = "Mon",
+ [2] = "Tue",
+ [3] = "Wed",
+ [4] = "Thu",
+ [5] = "Fri",
+ [6] = "Sat",
+ };
+
+ struct tm tm;
+ bool utc, us;
+ time_t sec;
+ size_t n;
+
+ assert(buf);
+ assert(style >= 0);
+ assert(style < _TIMESTAMP_STYLE_MAX);
+
+ if (!timestamp_is_set(t))
+ return NULL; /* Timestamp is unset */
+
+ if (style == TIMESTAMP_UNIX) {
+ if (l < (size_t) (1 + 1 + 1))
+ return NULL; /* not enough space for even the shortest of forms */
+
+ return snprintf_ok(buf, l, "@" USEC_FMT, t / USEC_PER_SEC); /* round down μs → s */
+ }
+
+ utc = IN_SET(style, TIMESTAMP_UTC, TIMESTAMP_US_UTC, TIMESTAMP_DATE);
+ us = IN_SET(style, TIMESTAMP_US, TIMESTAMP_US_UTC);
+
+ if (l < (size_t) (3 + /* week day */
+ 1 + 10 + /* space and date */
+ style == TIMESTAMP_DATE ? 0 :
+ (1 + 8 + /* space and time */
+ (us ? 1 + 6 : 0) + /* "." and microsecond part */
+ 1 + (utc ? 3 : 1)) + /* space and shortest possible zone */
+ 1))
+ return NULL; /* Not enough space even for the shortest form. */
+
+ /* Let's not format times with years > 9999 */
+ if (t > USEC_TIMESTAMP_FORMATTABLE_MAX) {
+ static const char* const xxx[_TIMESTAMP_STYLE_MAX] = {
+ [TIMESTAMP_PRETTY] = "--- XXXX-XX-XX XX:XX:XX",
+ [TIMESTAMP_US] = "--- XXXX-XX-XX XX:XX:XX.XXXXXX",
+ [TIMESTAMP_UTC] = "--- XXXX-XX-XX XX:XX:XX UTC",
+ [TIMESTAMP_US_UTC] = "--- XXXX-XX-XX XX:XX:XX.XXXXXX UTC",
+ [TIMESTAMP_DATE] = "--- XXXX-XX-XX",
+ };
+
+ assert(l >= strlen(xxx[style]) + 1);
+ return strcpy(buf, xxx[style]);
+ }
+
+ sec = (time_t) (t / USEC_PER_SEC); /* Round down */
+
+ if (!localtime_or_gmtime_r(&sec, &tm, utc))
+ return NULL;
+
+ /* Start with the week day */
+ assert((size_t) tm.tm_wday < ELEMENTSOF(weekdays));
+ memcpy(buf, weekdays[tm.tm_wday], 4);
+
+ if (style == TIMESTAMP_DATE) {
+ /* Special format string if only date should be shown. */
+ if (strftime(buf + 3, l - 3, " %Y-%m-%d", &tm) <= 0)
+ return NULL; /* Doesn't fit */
+
+ return buf;
+ }
+
+ /* Add the main components */
+ if (strftime(buf + 3, l - 3, " %Y-%m-%d %H:%M:%S", &tm) <= 0)
+ return NULL; /* Doesn't fit */
+
+ /* Append the microseconds part, if that's requested */
+ if (us) {
+ n = strlen(buf);
+ if (n + 8 > l)
+ return NULL; /* Microseconds part doesn't fit. */
+
+ sprintf(buf + n, ".%06"PRI_USEC, t % USEC_PER_SEC);
+ }
+
+ /* Append the timezone */
+ n = strlen(buf);
+ if (utc) {
+ /* If this is UTC then let's explicitly use the "UTC" string here, because gmtime_r()
+ * normally uses the obsolete "GMT" instead. */
+ if (n + 5 > l)
+ return NULL; /* "UTC" doesn't fit. */
+
+ strcpy(buf + n, " UTC");
+
+ } else if (!isempty(tm.tm_zone)) {
+ size_t tn;
+
+ /* An explicit timezone is specified, let's use it, if it fits */
+ tn = strlen(tm.tm_zone);
+ if (n + 1 + tn + 1 > l) {
+ /* The full time zone does not fit in. Yuck. */
+
+ if (n + 1 + _POSIX_TZNAME_MAX + 1 > l)
+ return NULL; /* Not even enough space for the POSIX minimum (of 6)? In that
+ * case, complain that it doesn't fit. */
+
+ /* So the time zone doesn't fit in fully, but the caller passed enough space for the
+ * POSIX minimum time zone length. In this case suppress the timezone entirely, in
+ * order not to dump an overly long, hard to read string on the user. This should be
+ * safe, because the user will assume the local timezone anyway if none is shown. And
+ * so does parse_timestamp(). */
+ } else {
+ buf[n++] = ' ';
+ strcpy(buf + n, tm.tm_zone);
+ }
+ }
+
+ return buf;
+}
+
+char* format_timestamp_relative_full(char *buf, size_t l, usec_t t, clockid_t clock, bool implicit_left) {
+ const char *s;
+ usec_t n, d;
+
+ assert(buf);
+
+ if (!timestamp_is_set(t))
+ return NULL;
+
+ n = now(clock);
+ if (n > t) {
+ d = n - t;
+ s = " ago";
+ } else {
+ d = t - n;
+ s = implicit_left ? "" : " left";
+ }
+
+ if (d >= USEC_PER_YEAR) {
+ usec_t years = d / USEC_PER_YEAR;
+ usec_t months = (d % USEC_PER_YEAR) / USEC_PER_MONTH;
+
+ (void) snprintf(buf, l, USEC_FMT " %s " USEC_FMT " %s%s",
+ years,
+ years == 1 ? "year" : "years",
+ months,
+ months == 1 ? "month" : "months",
+ s);
+ } else if (d >= USEC_PER_MONTH) {
+ usec_t months = d / USEC_PER_MONTH;
+ usec_t days = (d % USEC_PER_MONTH) / USEC_PER_DAY;
+
+ (void) snprintf(buf, l, USEC_FMT " %s " USEC_FMT " %s%s",
+ months,
+ months == 1 ? "month" : "months",
+ days,
+ days == 1 ? "day" : "days",
+ s);
+ } else if (d >= USEC_PER_WEEK) {
+ usec_t weeks = d / USEC_PER_WEEK;
+ usec_t days = (d % USEC_PER_WEEK) / USEC_PER_DAY;
+
+ (void) snprintf(buf, l, USEC_FMT " %s " USEC_FMT " %s%s",
+ weeks,
+ weeks == 1 ? "week" : "weeks",
+ days,
+ days == 1 ? "day" : "days",
+ s);
+ } else if (d >= 2*USEC_PER_DAY)
+ (void) snprintf(buf, l, USEC_FMT " days%s", d / USEC_PER_DAY,s);
+ else if (d >= 25*USEC_PER_HOUR)
+ (void) snprintf(buf, l, "1 day " USEC_FMT "h%s",
+ (d - USEC_PER_DAY) / USEC_PER_HOUR, s);
+ else if (d >= 6*USEC_PER_HOUR)
+ (void) snprintf(buf, l, USEC_FMT "h%s",
+ d / USEC_PER_HOUR, s);
+ else if (d >= USEC_PER_HOUR)
+ (void) snprintf(buf, l, USEC_FMT "h " USEC_FMT "min%s",
+ d / USEC_PER_HOUR,
+ (d % USEC_PER_HOUR) / USEC_PER_MINUTE, s);
+ else if (d >= 5*USEC_PER_MINUTE)
+ (void) snprintf(buf, l, USEC_FMT "min%s",
+ d / USEC_PER_MINUTE, s);
+ else if (d >= USEC_PER_MINUTE)
+ (void) snprintf(buf, l, USEC_FMT "min " USEC_FMT "s%s",
+ d / USEC_PER_MINUTE,
+ (d % USEC_PER_MINUTE) / USEC_PER_SEC, s);
+ else if (d >= USEC_PER_SEC)
+ (void) snprintf(buf, l, USEC_FMT "s%s",
+ d / USEC_PER_SEC, s);
+ else if (d >= USEC_PER_MSEC)
+ (void) snprintf(buf, l, USEC_FMT "ms%s",
+ d / USEC_PER_MSEC, s);
+ else if (d > 0)
+ (void) snprintf(buf, l, USEC_FMT"us%s",
+ d, s);
+ else
+ (void) snprintf(buf, l, "now");
+
+ buf[l-1] = 0;
+ return buf;
+}
+
+char* format_timespan(char *buf, size_t l, usec_t t, usec_t accuracy) {
+ static const struct {
+ const char *suffix;
+ usec_t usec;
+ } table[] = {
+ { "y", USEC_PER_YEAR },
+ { "month", USEC_PER_MONTH },
+ { "w", USEC_PER_WEEK },
+ { "d", USEC_PER_DAY },
+ { "h", USEC_PER_HOUR },
+ { "min", USEC_PER_MINUTE },
+ { "s", USEC_PER_SEC },
+ { "ms", USEC_PER_MSEC },
+ { "us", 1 },
+ };
+
+ char *p = ASSERT_PTR(buf);
+ bool something = false;
+
+ assert(l > 0);
+
+ if (t == USEC_INFINITY) {
+ strncpy(p, "infinity", l-1);
+ p[l-1] = 0;
+ return p;
+ }
+
+ if (t <= 0) {
+ strncpy(p, "0", l-1);
+ p[l-1] = 0;
+ return p;
+ }
+
+ /* The result of this function can be parsed with parse_sec */
+
+ for (size_t i = 0; i < ELEMENTSOF(table); i++) {
+ int k = 0;
+ size_t n;
+ bool done = false;
+ usec_t a, b;
+
+ if (t <= 0)
+ break;
+
+ if (t < accuracy && something)
+ break;
+
+ if (t < table[i].usec)
+ continue;
+
+ if (l <= 1)
+ break;
+
+ a = t / table[i].usec;
+ b = t % table[i].usec;
+
+ /* Let's see if we should shows this in dot notation */
+ if (t < USEC_PER_MINUTE && b > 0) {
+ signed char j = 0;
+
+ for (usec_t cc = table[i].usec; cc > 1; cc /= 10)
+ j++;
+
+ for (usec_t cc = accuracy; cc > 1; cc /= 10) {
+ b /= 10;
+ j--;
+ }
+
+ if (j > 0) {
+ k = snprintf(p, l,
+ "%s"USEC_FMT".%0*"PRI_USEC"%s",
+ p > buf ? " " : "",
+ a,
+ j,
+ b,
+ table[i].suffix);
+
+ t = 0;
+ done = true;
+ }
+ }
+
+ /* No? Then let's show it normally */
+ if (!done) {
+ k = snprintf(p, l,
+ "%s"USEC_FMT"%s",
+ p > buf ? " " : "",
+ a,
+ table[i].suffix);
+
+ t = b;
+ }
+
+ n = MIN((size_t) k, l-1);
+
+ l -= n;
+ p += n;
+
+ something = true;
+ }
+
+ *p = 0;
+
+ return buf;
+}
+
+static int parse_timestamp_impl(
+ const char *t,
+ size_t max_len,
+ bool utc,
+ int isdst,
+ long gmtoff,
+ usec_t *ret) {
+
+ static const struct {
+ const char *name;
+ const int nr;
+ } day_nr[] = {
+ { "Sunday", 0 },
+ { "Sun", 0 },
+ { "Monday", 1 },
+ { "Mon", 1 },
+ { "Tuesday", 2 },
+ { "Tue", 2 },
+ { "Wednesday", 3 },
+ { "Wed", 3 },
+ { "Thursday", 4 },
+ { "Thu", 4 },
+ { "Friday", 5 },
+ { "Fri", 5 },
+ { "Saturday", 6 },
+ { "Sat", 6 },
+ };
+
+ _cleanup_free_ char *t_alloc = NULL;
+ usec_t usec, plus = 0, minus = 0;
+ bool with_tz = false;
+ int r, weekday = -1;
+ unsigned fractional = 0;
+ const char *k;
+ struct tm tm, copy;
+ time_t sec;
+
+ /* Allowed syntaxes:
+ *
+ * 2012-09-22 16:34:22.1[2[3[4[5[6]]]]]
+ * 2012-09-22 16:34:22 (µsec will be set to 0)
+ * 2012-09-22 16:34 (seconds will be set to 0)
+ * 2012-09-22T16:34:22.1[2[3[4[5[6]]]]]
+ * 2012-09-22T16:34:22 (µsec will be set to 0)
+ * 2012-09-22T16:34 (seconds will be set to 0)
+ * 2012-09-22 (time will be set to 00:00:00)
+ * 16:34:22 (date will be set to today)
+ * 16:34 (date will be set to today, seconds to 0)
+ * now
+ * yesterday (time is set to 00:00:00)
+ * today (time is set to 00:00:00)
+ * tomorrow (time is set to 00:00:00)
+ * +5min
+ * -5days
+ * @2147483647 (seconds since epoch)
+ *
+ * Note, on DST change, 00:00:00 may not exist and in that case the time part may be shifted.
+ * E.g. "Sun 2023-03-13 America/Havana" is parsed as "Sun 2023-03-13 01:00:00 CDT".
+ *
+ * A simplified strptime-spelled RFC3339 ABNF looks like
+ * "%Y-%m-%d" "T" "%H" ":" "%M" ":" "%S" [".%N"] ("Z" / (("+" / "-") "%H:%M"))
+ * We additionally allow no seconds and inherited timezone
+ * for symmetry with our other syntaxes and improved interactive usability:
+ * "%Y-%m-%d" "T" "%H" ":" "%M" ":" ["%S" [".%N"]] ["Z" / (("+" / "-") "%H:%M")]
+ * RFC3339 defines time-secfrac to as "." 1*DIGIT, but we limit to 6 digits,
+ * since we're limited to 1µs resolution.
+ * We also accept "Sat 2012-09-22T16:34:22", RFC3339 warns against it.
+ */
+
+ assert(t);
+
+ if (max_len != SIZE_MAX) {
+ /* If the input string contains timezone, then cut it here. */
+
+ if (max_len == 0) /* Can't be the only field */
+ return -EINVAL;
+
+ t_alloc = strndup(t, max_len);
+ if (!t_alloc)
+ return -ENOMEM;
+
+ t = t_alloc;
+ with_tz = true;
+ }
+
+ if (utc) {
+ /* glibc accepts gmtoff more than 24 hours, but we refuse it. */
+ if ((usec_t) labs(gmtoff) * USEC_PER_SEC > USEC_PER_DAY)
+ return -EINVAL;
+ } else {
+ if (gmtoff != 0)
+ return -EINVAL;
+ }
+
+ if (t[0] == '@' && !with_tz)
+ return parse_sec(t + 1, ret);
+
+ usec = now(CLOCK_REALTIME);
+
+ if (!with_tz) {
+ if (streq(t, "now"))
+ goto finish;
+
+ if (t[0] == '+') {
+ r = parse_sec(t+1, &plus);
+ if (r < 0)
+ return r;
+
+ goto finish;
+ }
+
+ if (t[0] == '-') {
+ r = parse_sec(t+1, &minus);
+ if (r < 0)
+ return r;
+
+ goto finish;
+ }
+
+ if ((k = endswith(t, " ago"))) {
+ _cleanup_free_ char *buf = NULL;
+
+ buf = strndup(t, k - t);
+ if (!buf)
+ return -ENOMEM;
+
+ r = parse_sec(buf, &minus);
+ if (r < 0)
+ return r;
+
+ goto finish;
+ }
+
+ if ((k = endswith(t, " left"))) {
+ _cleanup_free_ char *buf = NULL;
+
+ buf = strndup(t, k - t);
+ if (!buf)
+ return -ENOMEM;
+
+ r = parse_sec(buf, &plus);
+ if (r < 0)
+ return r;
+
+ goto finish;
+ }
+ }
+
+ sec = (time_t) (usec / USEC_PER_SEC);
+
+ if (!localtime_or_gmtime_r(&sec, &tm, utc))
+ return -EINVAL;
+
+ tm.tm_isdst = isdst;
+
+ if (streq(t, "today")) {
+ tm.tm_sec = tm.tm_min = tm.tm_hour = 0;
+ goto from_tm;
+
+ } else if (streq(t, "yesterday")) {
+ tm.tm_mday--;
+ tm.tm_sec = tm.tm_min = tm.tm_hour = 0;
+ goto from_tm;
+
+ } else if (streq(t, "tomorrow")) {
+ tm.tm_mday++;
+ tm.tm_sec = tm.tm_min = tm.tm_hour = 0;
+ goto from_tm;
+ }
+
+ for (size_t i = 0; i < ELEMENTSOF(day_nr); i++) {
+ k = startswith_no_case(t, day_nr[i].name);
+ if (!k || *k != ' ')
+ continue;
+
+ weekday = day_nr[i].nr;
+ t = k + 1;
+ break;
+ }
+
+ copy = tm;
+ k = strptime(t, "%y-%m-%d %H:%M:%S", &tm);
+ if (k) {
+ if (*k == '.')
+ goto parse_usec;
+ else if (*k == 0)
+ goto from_tm;
+ }
+
+ /* Our "canonical" RFC3339 syntax variant */
+ tm = copy;
+ k = strptime(t, "%Y-%m-%d %H:%M:%S", &tm);
+ if (k) {
+ if (*k == '.')
+ goto parse_usec;
+ else if (*k == 0)
+ goto from_tm;
+ }
+
+ /* RFC3339 syntax */
+ tm = copy;
+ k = strptime(t, "%Y-%m-%dT%H:%M:%S", &tm);
+ if (k) {
+ if (*k == '.')
+ goto parse_usec;
+ else if (*k == 0)
+ goto from_tm;
+ }
+
+ /* Support OUTPUT_SHORT and OUTPUT_SHORT_PRECISE formats */
+ tm = copy;
+ k = strptime(t, "%b %d %H:%M:%S", &tm);
+ if (k) {
+ if (*k == '.')
+ goto parse_usec;
+ else if (*k == 0)
+ goto from_tm;
+ }
+
+ tm = copy;
+ k = strptime(t, "%y-%m-%d %H:%M", &tm);
+ if (k && *k == 0) {
+ tm.tm_sec = 0;
+ goto from_tm;
+ }
+
+ /* Our "canonical" RFC3339 syntax variant without seconds */
+ tm = copy;
+ k = strptime(t, "%Y-%m-%d %H:%M", &tm);
+ if (k && *k == 0) {
+ tm.tm_sec = 0;
+ goto from_tm;
+ }
+
+ /* RFC3339 syntax without seconds */
+ tm = copy;
+ k = strptime(t, "%Y-%m-%dT%H:%M", &tm);
+ if (k && *k == 0) {
+ tm.tm_sec = 0;
+ goto from_tm;
+ }
+
+ tm = copy;
+ k = strptime(t, "%y-%m-%d", &tm);
+ if (k && *k == 0) {
+ tm.tm_sec = tm.tm_min = tm.tm_hour = 0;
+ goto from_tm;
+ }
+
+ tm = copy;
+ k = strptime(t, "%Y-%m-%d", &tm);
+ if (k && *k == 0) {
+ tm.tm_sec = tm.tm_min = tm.tm_hour = 0;
+ goto from_tm;
+ }
+
+ tm = copy;
+ k = strptime(t, "%H:%M:%S", &tm);
+ if (k) {
+ if (*k == '.')
+ goto parse_usec;
+ else if (*k == 0)
+ goto from_tm;
+ }
+
+ tm = copy;
+ k = strptime(t, "%H:%M", &tm);
+ if (k && *k == 0) {
+ tm.tm_sec = 0;
+ goto from_tm;
+ }
+
+ return -EINVAL;
+
+parse_usec:
+ k++;
+ r = parse_fractional_part_u(&k, 6, &fractional);
+ if (r < 0)
+ return -EINVAL;
+ if (*k != '\0')
+ return -EINVAL;
+
+from_tm:
+ assert(plus == 0);
+ assert(minus == 0);
+
+ if (weekday >= 0 && tm.tm_wday != weekday)
+ return -EINVAL;
+
+ if (gmtoff < 0) {
+ plus = -gmtoff * USEC_PER_SEC;
+
+ /* If gmtoff is negative, the string may be too old to be parsed as UTC.
+ * E.g. 1969-12-31 23:00:00 -06 == 1970-01-01 05:00:00 UTC
+ * We assumed that gmtoff is in the range of -24:00…+24:00, hence the only date we need to
+ * handle here is 1969-12-31. So, let's shift the date with one day, then subtract the shift
+ * later. */
+ if (tm.tm_year == 69 && tm.tm_mon == 11 && tm.tm_mday == 31) {
+ /* Thu 1970-01-01-00:00:00 */
+ tm.tm_year = 70;
+ tm.tm_mon = 0;
+ tm.tm_mday = 1;
+ tm.tm_wday = 4;
+ tm.tm_yday = 0;
+ minus = USEC_PER_DAY;
+ }
+ } else
+ minus = gmtoff * USEC_PER_SEC;
+
+ sec = mktime_or_timegm(&tm, utc);
+ if (sec < 0)
+ return -EINVAL;
+
+ usec = usec_add(sec * USEC_PER_SEC, fractional);
+
+finish:
+ usec = usec_add(usec, plus);
+
+ if (usec < minus)
+ return -EINVAL;
+
+ usec = usec_sub_unsigned(usec, minus);
+
+ if (usec > USEC_TIMESTAMP_FORMATTABLE_MAX)
+ return -EINVAL;
+
+ if (ret)
+ *ret = usec;
+ return 0;
+}
+
+static int parse_timestamp_maybe_with_tz(const char *t, size_t tz_offset, bool valid_tz, usec_t *ret) {
+ assert(t);
+
+ tzset();
+
+ for (int j = 0; j <= 1; j++) {
+ if (isempty(tzname[j]))
+ continue;
+
+ if (!streq(t + tz_offset, tzname[j]))
+ continue;
+
+ /* The specified timezone matches tzname[] of the local timezone. */
+ return parse_timestamp_impl(t, tz_offset - 1, /* utc = */ false, /* isdst = */ j, /* gmtoff = */ 0, ret);
+ }
+
+ /* If we know that the last word is a valid timezone (e.g. Asia/Tokyo), then simply drop the timezone
+ * and parse the remaining string as a local time. If we know that the last word is not a timezone,
+ * then assume that it is a part of the time and try to parse the whole string as a local time. */
+ return parse_timestamp_impl(t, valid_tz ? tz_offset - 1 : SIZE_MAX,
+ /* utc = */ false, /* isdst = */ -1, /* gmtoff = */ 0, ret);
+}
+
+typedef struct ParseTimestampResult {
+ usec_t usec;
+ int return_value;
+} ParseTimestampResult;
+
+int parse_timestamp(const char *t, usec_t *ret) {
+ ParseTimestampResult *shared, tmp;
+ const char *k, *tz, *current_tz;
+ size_t max_len, t_len;
+ struct tm tm;
+ int r;
+
+ assert(t);
+
+ t_len = strlen(t);
+ if (t_len > 2 && t[t_len - 1] == 'Z' && t[t_len - 2] != ' ') /* RFC3339-style welded UTC: "1985-04-12T23:20:50.52Z" */
+ return parse_timestamp_impl(t, t_len - 1, /* utc = */ true, /* isdst = */ -1, /* gmtoff = */ 0, ret);
+
+ if (t_len > 7 && IN_SET(t[t_len - 6], '+', '-') && t[t_len - 7] != ' ') { /* RFC3339-style welded offset: "1990-12-31T15:59:60-08:00" */
+ k = strptime(&t[t_len - 6], "%z", &tm);
+ if (k && *k == '\0')
+ return parse_timestamp_impl(t, t_len - 6, /* utc = */ true, /* isdst = */ -1, /* gmtoff = */ tm.tm_gmtoff, ret);
+ }
+
+ tz = strrchr(t, ' ');
+ if (!tz)
+ return parse_timestamp_impl(t, /* max_len = */ SIZE_MAX, /* utc = */ false, /* isdst = */ -1, /* gmtoff = */ 0, ret);
+
+ max_len = tz - t;
+ tz++;
+
+ /* Shortcut, parse the string as UTC. */
+ if (streq(tz, "UTC"))
+ return parse_timestamp_impl(t, max_len, /* utc = */ true, /* isdst = */ -1, /* gmtoff = */ 0, ret);
+
+ /* If the timezone is compatible with RFC-822/ISO 8601 (e.g. +06, or -03:00) then parse the string as
+ * UTC and shift the result. Note, this must be earlier than the timezone check with tzname[], as
+ * tzname[] may be in the same format. */
+ k = strptime(tz, "%z", &tm);
+ if (k && *k == '\0')
+ return parse_timestamp_impl(t, max_len, /* utc = */ true, /* isdst = */ -1, /* gmtoff = */ tm.tm_gmtoff, ret);
+
+ /* If the last word is not a timezone file (e.g. Asia/Tokyo), then let's check if it matches
+ * tzname[] of the local timezone, e.g. JST or CEST. */
+ if (!timezone_is_valid(tz, LOG_DEBUG))
+ return parse_timestamp_maybe_with_tz(t, tz - t, /* valid_tz = */ false, ret);
+
+ /* Shortcut. If the current $TZ is equivalent to the specified timezone, it is not necessary to fork
+ * the process. */
+ current_tz = getenv("TZ");
+ if (current_tz && *current_tz == ':' && streq(current_tz + 1, tz))
+ return parse_timestamp_maybe_with_tz(t, tz - t, /* valid_tz = */ true, ret);
+
+ /* Otherwise, to avoid polluting the current environment variables, let's fork the process and set
+ * the specified timezone in the child process. */
+
+ shared = mmap(NULL, sizeof *shared, PROT_READ|PROT_WRITE, MAP_SHARED|MAP_ANONYMOUS, -1, 0);
+ if (shared == MAP_FAILED)
+ return negative_errno();
+
+ r = safe_fork("(sd-timestamp)", FORK_RESET_SIGNALS|FORK_CLOSE_ALL_FDS|FORK_DEATHSIG_SIGKILL|FORK_WAIT, NULL);
+ if (r < 0) {
+ (void) munmap(shared, sizeof *shared);
+ return r;
+ }
+ if (r == 0) {
+ const char *colon_tz;
+
+ /* tzset(3) says $TZ should be prefixed with ":" if we reference timezone files */
+ colon_tz = strjoina(":", tz);
+
+ if (setenv("TZ", colon_tz, 1) != 0) {
+ shared->return_value = negative_errno();
+ _exit(EXIT_FAILURE);
+ }
+
+ shared->return_value = parse_timestamp_maybe_with_tz(t, tz - t, /* valid_tz = */ true, &shared->usec);
+
+ _exit(EXIT_SUCCESS);
+ }
+
+ tmp = *shared;
+ if (munmap(shared, sizeof *shared) != 0)
+ return negative_errno();
+
+ if (tmp.return_value == 0 && ret)
+ *ret = tmp.usec;
+
+ return tmp.return_value;
+}
+
+static const char* extract_multiplier(const char *p, usec_t *ret) {
+ static const struct {
+ const char *suffix;
+ usec_t usec;
+ } table[] = {
+ { "seconds", USEC_PER_SEC },
+ { "second", USEC_PER_SEC },
+ { "sec", USEC_PER_SEC },
+ { "s", USEC_PER_SEC },
+ { "minutes", USEC_PER_MINUTE },
+ { "minute", USEC_PER_MINUTE },
+ { "min", USEC_PER_MINUTE },
+ { "months", USEC_PER_MONTH },
+ { "month", USEC_PER_MONTH },
+ { "M", USEC_PER_MONTH },
+ { "msec", USEC_PER_MSEC },
+ { "ms", USEC_PER_MSEC },
+ { "m", USEC_PER_MINUTE },
+ { "hours", USEC_PER_HOUR },
+ { "hour", USEC_PER_HOUR },
+ { "hr", USEC_PER_HOUR },
+ { "h", USEC_PER_HOUR },
+ { "days", USEC_PER_DAY },
+ { "day", USEC_PER_DAY },
+ { "d", USEC_PER_DAY },
+ { "weeks", USEC_PER_WEEK },
+ { "week", USEC_PER_WEEK },
+ { "w", USEC_PER_WEEK },
+ { "years", USEC_PER_YEAR },
+ { "year", USEC_PER_YEAR },
+ { "y", USEC_PER_YEAR },
+ { "usec", 1ULL },
+ { "us", 1ULL },
+ { "μs", 1ULL }, /* U+03bc (aka GREEK SMALL LETTER MU) */
+ { "µs", 1ULL }, /* U+b5 (aka MICRO SIGN) */
+ };
+
+ assert(p);
+ assert(ret);
+
+ for (size_t i = 0; i < ELEMENTSOF(table); i++) {
+ char *e;
+
+ e = startswith(p, table[i].suffix);
+ if (e) {
+ *ret = table[i].usec;
+ return e;
+ }
+ }
+
+ return p;
+}
+
+int parse_time(const char *t, usec_t *ret, usec_t default_unit) {
+ const char *p, *s;
+ usec_t usec = 0;
+ bool something = false;
+
+ assert(t);
+ assert(default_unit > 0);
+
+ p = t;
+
+ p += strspn(p, WHITESPACE);
+ s = startswith(p, "infinity");
+ if (s) {
+ s += strspn(s, WHITESPACE);
+ if (*s != 0)
+ return -EINVAL;
+
+ if (ret)
+ *ret = USEC_INFINITY;
+ return 0;
+ }
+
+ for (;;) {
+ usec_t multiplier = default_unit, k;
+ long long l;
+ char *e;
+
+ p += strspn(p, WHITESPACE);
+
+ if (*p == 0) {
+ if (!something)
+ return -EINVAL;
+
+ break;
+ }
+
+ if (*p == '-') /* Don't allow "-0" */
+ return -ERANGE;
+
+ errno = 0;
+ l = strtoll(p, &e, 10);
+ if (errno > 0)
+ return -errno;
+ if (l < 0)
+ return -ERANGE;
+
+ if (*e == '.') {
+ p = e + 1;
+ p += strspn(p, DIGITS);
+ } else if (e == p)
+ return -EINVAL;
+ else
+ p = e;
+
+ s = extract_multiplier(p + strspn(p, WHITESPACE), &multiplier);
+ if (s == p && *s != '\0')
+ /* Don't allow '12.34.56', but accept '12.34 .56' or '12.34s.56' */
+ return -EINVAL;
+
+ p = s;
+
+ if ((usec_t) l >= USEC_INFINITY / multiplier)
+ return -ERANGE;
+
+ k = (usec_t) l * multiplier;
+ if (k >= USEC_INFINITY - usec)
+ return -ERANGE;
+
+ usec += k;
+
+ something = true;
+
+ if (*e == '.') {
+ usec_t m = multiplier / 10;
+ const char *b;
+
+ for (b = e + 1; *b >= '0' && *b <= '9'; b++, m /= 10) {
+ k = (usec_t) (*b - '0') * m;
+ if (k >= USEC_INFINITY - usec)
+ return -ERANGE;
+
+ usec += k;
+ }
+
+ /* Don't allow "0.-0", "3.+1", "3. 1", "3.sec" or "3.hoge" */
+ if (b == e + 1)
+ return -EINVAL;
+ }
+ }
+
+ if (ret)
+ *ret = usec;
+ return 0;
+}
+
+int parse_sec(const char *t, usec_t *ret) {
+ return parse_time(t, ret, USEC_PER_SEC);
+}
+
+int parse_sec_fix_0(const char *t, usec_t *ret) {
+ usec_t k;
+ int r;
+
+ assert(t);
+ assert(ret);
+
+ r = parse_sec(t, &k);
+ if (r < 0)
+ return r;
+
+ *ret = k == 0 ? USEC_INFINITY : k;
+ return r;
+}
+
+int parse_sec_def_infinity(const char *t, usec_t *ret) {
+ assert(t);
+ assert(ret);
+
+ t += strspn(t, WHITESPACE);
+ if (isempty(t)) {
+ *ret = USEC_INFINITY;
+ return 0;
+ }
+ return parse_sec(t, ret);
+}
+
+static const char* extract_nsec_multiplier(const char *p, nsec_t *ret) {
+ static const struct {
+ const char *suffix;
+ nsec_t nsec;
+ } table[] = {
+ { "seconds", NSEC_PER_SEC },
+ { "second", NSEC_PER_SEC },
+ { "sec", NSEC_PER_SEC },
+ { "s", NSEC_PER_SEC },
+ { "minutes", NSEC_PER_MINUTE },
+ { "minute", NSEC_PER_MINUTE },
+ { "min", NSEC_PER_MINUTE },
+ { "months", NSEC_PER_MONTH },
+ { "month", NSEC_PER_MONTH },
+ { "M", NSEC_PER_MONTH },
+ { "msec", NSEC_PER_MSEC },
+ { "ms", NSEC_PER_MSEC },
+ { "m", NSEC_PER_MINUTE },
+ { "hours", NSEC_PER_HOUR },
+ { "hour", NSEC_PER_HOUR },
+ { "hr", NSEC_PER_HOUR },
+ { "h", NSEC_PER_HOUR },
+ { "days", NSEC_PER_DAY },
+ { "day", NSEC_PER_DAY },
+ { "d", NSEC_PER_DAY },
+ { "weeks", NSEC_PER_WEEK },
+ { "week", NSEC_PER_WEEK },
+ { "w", NSEC_PER_WEEK },
+ { "years", NSEC_PER_YEAR },
+ { "year", NSEC_PER_YEAR },
+ { "y", NSEC_PER_YEAR },
+ { "usec", NSEC_PER_USEC },
+ { "us", NSEC_PER_USEC },
+ { "μs", NSEC_PER_USEC }, /* U+03bc (aka GREEK LETTER MU) */
+ { "µs", NSEC_PER_USEC }, /* U+b5 (aka MICRO SIGN) */
+ { "nsec", 1ULL },
+ { "ns", 1ULL },
+ { "", 1ULL }, /* default is nsec */
+ };
+ size_t i;
+
+ assert(p);
+ assert(ret);
+
+ for (i = 0; i < ELEMENTSOF(table); i++) {
+ char *e;
+
+ e = startswith(p, table[i].suffix);
+ if (e) {
+ *ret = table[i].nsec;
+ return e;
+ }
+ }
+
+ return p;
+}
+
+int parse_nsec(const char *t, nsec_t *ret) {
+ const char *p, *s;
+ nsec_t nsec = 0;
+ bool something = false;
+
+ assert(t);
+ assert(ret);
+
+ p = t;
+
+ p += strspn(p, WHITESPACE);
+ s = startswith(p, "infinity");
+ if (s) {
+ s += strspn(s, WHITESPACE);
+ if (*s != 0)
+ return -EINVAL;
+
+ *ret = NSEC_INFINITY;
+ return 0;
+ }
+
+ for (;;) {
+ nsec_t multiplier = 1, k;
+ long long l;
+ char *e;
+
+ p += strspn(p, WHITESPACE);
+
+ if (*p == 0) {
+ if (!something)
+ return -EINVAL;
+
+ break;
+ }
+
+ if (*p == '-') /* Don't allow "-0" */
+ return -ERANGE;
+
+ errno = 0;
+ l = strtoll(p, &e, 10);
+ if (errno > 0)
+ return -errno;
+ if (l < 0)
+ return -ERANGE;
+
+ if (*e == '.') {
+ p = e + 1;
+ p += strspn(p, DIGITS);
+ } else if (e == p)
+ return -EINVAL;
+ else
+ p = e;
+
+ s = extract_nsec_multiplier(p + strspn(p, WHITESPACE), &multiplier);
+ if (s == p && *s != '\0')
+ /* Don't allow '12.34.56', but accept '12.34 .56' or '12.34s.56' */
+ return -EINVAL;
+
+ p = s;
+
+ if ((nsec_t) l >= NSEC_INFINITY / multiplier)
+ return -ERANGE;
+
+ k = (nsec_t) l * multiplier;
+ if (k >= NSEC_INFINITY - nsec)
+ return -ERANGE;
+
+ nsec += k;
+
+ something = true;
+
+ if (*e == '.') {
+ nsec_t m = multiplier / 10;
+ const char *b;
+
+ for (b = e + 1; *b >= '0' && *b <= '9'; b++, m /= 10) {
+ k = (nsec_t) (*b - '0') * m;
+ if (k >= NSEC_INFINITY - nsec)
+ return -ERANGE;
+
+ nsec += k;
+ }
+
+ /* Don't allow "0.-0", "3.+1", "3. 1", "3.sec" or "3.hoge" */
+ if (b == e + 1)
+ return -EINVAL;
+ }
+ }
+
+ *ret = nsec;
+
+ return 0;
+}
+
+static int get_timezones_from_zone1970_tab(char ***ret) {
+ _cleanup_fclose_ FILE *f = NULL;
+ _cleanup_strv_free_ char **zones = NULL;
+ int r;
+
+ assert(ret);
+
+ f = fopen("/usr/share/zoneinfo/zone1970.tab", "re");
+ if (!f)
+ return -errno;
+
+ for (;;) {
+ _cleanup_free_ char *line = NULL, *cc = NULL, *co = NULL, *tz = NULL;
+
+ r = read_line(f, LONG_LINE_MAX, &line);
+ if (r < 0)
+ return r;
+ if (r == 0)
+ break;
+
+ const char *p = line;
+
+ /* Line format is:
+ * 'country codes' 'coordinates' 'timezone' 'comments' */
+ r = extract_many_words(&p, NULL, 0, &cc, &co, &tz, NULL);
+ if (r < 0)
+ continue;
+
+ /* Lines that start with # are comments. */
+ if (*cc == '#')
+ continue;
+
+ r = strv_extend(&zones, tz);
+ if (r < 0)
+ return r;
+ }
+
+ *ret = TAKE_PTR(zones);
+ return 0;
+}
+
+static int get_timezones_from_tzdata_zi(char ***ret) {
+ _cleanup_fclose_ FILE *f = NULL;
+ _cleanup_strv_free_ char **zones = NULL;
+ int r;
+
+ assert(ret);
+
+ f = fopen("/usr/share/zoneinfo/tzdata.zi", "re");
+ if (!f)
+ return -errno;
+
+ for (;;) {
+ _cleanup_free_ char *line = NULL, *type = NULL, *f1 = NULL, *f2 = NULL;
+
+ r = read_line(f, LONG_LINE_MAX, &line);
+ if (r < 0)
+ return r;
+ if (r == 0)
+ break;
+
+ const char *p = line;
+
+ /* The only lines we care about are Zone and Link lines.
+ * Zone line format is:
+ * 'Zone' 'timezone' ...
+ * Link line format is:
+ * 'Link' 'target' 'alias'
+ * See 'man zic' for more detail. */
+ r = extract_many_words(&p, NULL, 0, &type, &f1, &f2, NULL);
+ if (r < 0)
+ continue;
+
+ char *tz;
+ if (IN_SET(*type, 'Z', 'z'))
+ /* Zone lines have timezone in field 1. */
+ tz = f1;
+ else if (IN_SET(*type, 'L', 'l'))
+ /* Link lines have timezone in field 2. */
+ tz = f2;
+ else
+ /* Not a line we care about. */
+ continue;
+
+ r = strv_extend(&zones, tz);
+ if (r < 0)
+ return r;
+ }
+
+ *ret = TAKE_PTR(zones);
+ return 0;
+}
+
+int get_timezones(char ***ret) {
+ _cleanup_strv_free_ char **zones = NULL;
+ int r;
+
+ assert(ret);
+
+ r = get_timezones_from_tzdata_zi(&zones);
+ if (r == -ENOENT) {
+ log_debug_errno(r, "Could not get timezone data from tzdata.zi, using zone1970.tab: %m");
+ r = get_timezones_from_zone1970_tab(&zones);
+ if (r == -ENOENT)
+ log_debug_errno(r, "Could not get timezone data from zone1970.tab, using UTC: %m");
+ }
+ if (r < 0 && r != -ENOENT)
+ return r;
+
+ /* Always include UTC */
+ r = strv_extend(&zones, "UTC");
+ if (r < 0)
+ return -ENOMEM;
+
+ strv_sort(zones);
+ strv_uniq(zones);
+
+ *ret = TAKE_PTR(zones);
+ return 0;
+}
+
+int verify_timezone(const char *name, int log_level) {
+ bool slash = false;
+ const char *p, *t;
+ _cleanup_close_ int fd = -EBADF;
+ char buf[4];
+ int r;
+
+ if (isempty(name))
+ return -EINVAL;
+
+ /* Always accept "UTC" as valid timezone, since it's the fallback, even if user has no timezones installed. */
+ if (streq(name, "UTC"))
+ return 0;
+
+ if (name[0] == '/')
+ return -EINVAL;
+
+ for (p = name; *p; p++) {
+ if (!ascii_isdigit(*p) &&
+ !ascii_isalpha(*p) &&
+ !IN_SET(*p, '-', '_', '+', '/'))
+ return -EINVAL;
+
+ if (*p == '/') {
+
+ if (slash)
+ return -EINVAL;
+
+ slash = true;
+ } else
+ slash = false;
+ }
+
+ if (slash)
+ return -EINVAL;
+
+ if (p - name >= PATH_MAX)
+ return -ENAMETOOLONG;
+
+ t = strjoina("/usr/share/zoneinfo/", name);
+
+ fd = open(t, O_RDONLY|O_CLOEXEC);
+ if (fd < 0)
+ return log_full_errno(log_level, errno, "Failed to open timezone file '%s': %m", t);
+
+ r = fd_verify_regular(fd);
+ if (r < 0)
+ return log_full_errno(log_level, r, "Timezone file '%s' is not a regular file: %m", t);
+
+ r = loop_read_exact(fd, buf, 4, false);
+ if (r < 0)
+ return log_full_errno(log_level, r, "Failed to read from timezone file '%s': %m", t);
+
+ /* Magic from tzfile(5) */
+ if (memcmp(buf, "TZif", 4) != 0)
+ return log_full_errno(log_level, SYNTHETIC_ERRNO(EBADMSG),
+ "Timezone file '%s' has wrong magic bytes", t);
+
+ return 0;
+}
+
+bool clock_supported(clockid_t clock) {
+ struct timespec ts;
+
+ switch (clock) {
+
+ case CLOCK_MONOTONIC:
+ case CLOCK_REALTIME:
+ case CLOCK_BOOTTIME:
+ /* These three are always available in our baseline, and work in timerfd, as of kernel 3.15 */
+ return true;
+
+ default:
+ /* For everything else, check properly */
+ return clock_gettime(clock, &ts) >= 0;
+ }
+}
+
+int get_timezone(char **ret) {
+ _cleanup_free_ char *t = NULL;
+ const char *e;
+ char *z;
+ int r;
+
+ assert(ret);
+
+ r = readlink_malloc("/etc/localtime", &t);
+ if (r == -ENOENT) {
+ /* If the symlink does not exist, assume "UTC", like glibc does */
+ z = strdup("UTC");
+ if (!z)
+ return -ENOMEM;
+
+ *ret = z;
+ return 0;
+ }
+ if (r < 0)
+ return r; /* returns EINVAL if not a symlink */
+
+ e = PATH_STARTSWITH_SET(t, "/usr/share/zoneinfo/", "../usr/share/zoneinfo/");
+ if (!e)
+ return -EINVAL;
+
+ if (!timezone_is_valid(e, LOG_DEBUG))
+ return -EINVAL;
+
+ z = strdup(e);
+ if (!z)
+ return -ENOMEM;
+
+ *ret = z;
+ return 0;
+}
+
+time_t mktime_or_timegm(struct tm *tm, bool utc) {
+ assert(tm);
+
+ return utc ? timegm(tm) : mktime(tm);
+}
+
+struct tm *localtime_or_gmtime_r(const time_t *t, struct tm *tm, bool utc) {
+ assert(t);
+ assert(tm);
+
+ return utc ? gmtime_r(t, tm) : localtime_r(t, tm);
+}
+
+static uint32_t sysconf_clock_ticks_cached(void) {
+ static thread_local uint32_t hz = 0;
+ long r;
+
+ if (hz == 0) {
+ r = sysconf(_SC_CLK_TCK);
+
+ assert(r > 0);
+ hz = r;
+ }
+
+ return hz;
+}
+
+uint32_t usec_to_jiffies(usec_t u) {
+ uint32_t hz = sysconf_clock_ticks_cached();
+ return DIV_ROUND_UP(u, USEC_PER_SEC / hz);
+}
+
+usec_t jiffies_to_usec(uint32_t j) {
+ uint32_t hz = sysconf_clock_ticks_cached();
+ return DIV_ROUND_UP(j * USEC_PER_SEC, hz);
+}
+
+usec_t usec_shift_clock(usec_t x, clockid_t from, clockid_t to) {
+ usec_t a, b;
+
+ if (x == USEC_INFINITY)
+ return USEC_INFINITY;
+ if (map_clock_id(from) == map_clock_id(to))
+ return x;
+
+ a = now(from);
+ b = now(to);
+
+ if (x > a)
+ /* x lies in the future */
+ return usec_add(b, usec_sub_unsigned(x, a));
+ else
+ /* x lies in the past */
+ return usec_sub_unsigned(b, usec_sub_unsigned(a, x));
+}
+
+bool in_utc_timezone(void) {
+ tzset();
+
+ return timezone == 0 && daylight == 0;
+}
+
+int time_change_fd(void) {
+
+ /* We only care for the cancellation event, hence we set the timeout to the latest possible value. */
+ static const struct itimerspec its = {
+ .it_value.tv_sec = TIME_T_MAX,
+ };
+
+ _cleanup_close_ int fd = -EBADF;
+
+ assert_cc(sizeof(time_t) == sizeof(TIME_T_MAX));
+
+ /* Uses TFD_TIMER_CANCEL_ON_SET to get notifications whenever CLOCK_REALTIME makes a jump relative to
+ * CLOCK_MONOTONIC. */
+
+ fd = timerfd_create(CLOCK_REALTIME, TFD_NONBLOCK|TFD_CLOEXEC);
+ if (fd < 0)
+ return -errno;
+
+ if (timerfd_settime(fd, TFD_TIMER_ABSTIME|TFD_TIMER_CANCEL_ON_SET, &its, NULL) >= 0)
+ return TAKE_FD(fd);
+
+ /* So apparently there are systems where time_t is 64-bit, but the kernel actually doesn't support
+ * 64-bit time_t. In that case configuring a timer to TIME_T_MAX will fail with EOPNOTSUPP or a
+ * similar error. If that's the case let's try with INT32_MAX instead, maybe that works. It's a bit
+ * of a black magic thing though, but what can we do?
+ *
+ * We don't want this code on x86-64, hence let's conditionalize this for systems with 64-bit time_t
+ * but where "long" is shorter than 64-bit, i.e. 32-bit archs.
+ *
+ * See: https://github.com/systemd/systemd/issues/14362 */
+
+#if SIZEOF_TIME_T == 8 && ULONG_MAX < UINT64_MAX
+ if (ERRNO_IS_NOT_SUPPORTED(errno) || errno == EOVERFLOW) {
+ static const struct itimerspec its32 = {
+ .it_value.tv_sec = INT32_MAX,
+ };
+
+ if (timerfd_settime(fd, TFD_TIMER_ABSTIME|TFD_TIMER_CANCEL_ON_SET, &its32, NULL) >= 0)
+ return TAKE_FD(fd);
+ }
+#endif
+
+ return -errno;
+}
+
+static const char* const timestamp_style_table[_TIMESTAMP_STYLE_MAX] = {
+ [TIMESTAMP_PRETTY] = "pretty",
+ [TIMESTAMP_US] = "us",
+ [TIMESTAMP_UTC] = "utc",
+ [TIMESTAMP_US_UTC] = "us+utc",
+ [TIMESTAMP_UNIX] = "unix",
+};
+
+/* Use the macro for enum → string to allow for aliases */
+DEFINE_STRING_TABLE_LOOKUP_TO_STRING(timestamp_style, TimestampStyle);
+
+/* For the string → enum mapping we use the generic implementation, but also support two aliases */
+TimestampStyle timestamp_style_from_string(const char *s) {
+ TimestampStyle t;
+
+ t = (TimestampStyle) string_table_lookup(timestamp_style_table, ELEMENTSOF(timestamp_style_table), s);
+ if (t >= 0)
+ return t;
+ if (STRPTR_IN_SET(s, "µs", "μs")) /* accept both µ symbols in unicode, i.e. micro symbol + Greek small letter mu. */
+ return TIMESTAMP_US;
+ if (STRPTR_IN_SET(s, "µs+utc", "μs+utc"))
+ return TIMESTAMP_US_UTC;
+ return t;
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-05-30 17:01:37 +0000