build-sys: split internal basic/ library from shared/

basic/      can be used by everything
            cannot use anything outside of basic/

libsystemd/ can use basic/
            cannot use shared/

shared/     can use libsystemd/

1 files changed, 997 insertions, 0 deletions

diff --git a/src/basic/time-util.c b/src/basic/time-util.c
new file mode 100644
index 0000000000..12f1b193be
--- /dev/null
+++ b/src/basic/time-util.c
@@ -0,0 +1,997 @@
+/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
+
+/***
+  This file is part of systemd.
+
+  Copyright 2010 Lennart Poettering
+
+  systemd is free software; you can redistribute it and/or modify it
+  under the terms of the GNU Lesser General Public License as published by
+  the Free Software Foundation; either version 2.1 of the License, or
+  (at your option) any later version.
+
+  systemd 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
+  Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public License
+  along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include <time.h>
+#include <string.h>
+#include <sys/timex.h>
+#include <sys/timerfd.h>
+
+#include "util.h"
+#include "time-util.h"
+#include "strv.h"
+
+usec_t now(clockid_t clock_id) {
+        struct timespec ts;
+
+        assert_se(clock_gettime(clock_id, &ts) == 0);
+
+        return timespec_load(&ts);
+}
+
+dual_timestamp* dual_timestamp_get(dual_timestamp *ts) {
+        assert(ts);
+
+        ts->realtime = now(CLOCK_REALTIME);
+        ts->monotonic = now(CLOCK_MONOTONIC);
+
+        return ts;
+}
+
+dual_timestamp* dual_timestamp_from_realtime(dual_timestamp *ts, usec_t u) {
+        int64_t delta;
+        assert(ts);
+
+        if (u == USEC_INFINITY || u <= 0) {
+                ts->realtime = ts->monotonic = u;
+                return ts;
+        }
+
+        ts->realtime = u;
+
+        delta = (int64_t) now(CLOCK_REALTIME) - (int64_t) u;
+        ts->monotonic = now(CLOCK_MONOTONIC);
+
+        if ((int64_t) ts->monotonic > delta)
+                ts->monotonic -= delta;
+        else
+                ts->monotonic = 0;
+
+        return ts;
+}
+
+dual_timestamp* dual_timestamp_from_monotonic(dual_timestamp *ts, usec_t u) {
+        int64_t delta;
+        assert(ts);
+
+        if (u == USEC_INFINITY) {
+                ts->realtime = ts->monotonic = USEC_INFINITY;
+                return ts;
+        }
+
+        ts->monotonic = u;
+        delta = (int64_t) now(CLOCK_MONOTONIC) - (int64_t) u;
+
+        ts->realtime = now(CLOCK_REALTIME);
+        if ((int64_t) ts->realtime > delta)
+                ts->realtime -= delta;
+        else
+                ts->realtime = 0;
+
+        return ts;
+}
+
+usec_t timespec_load(const struct timespec *ts) {
+        assert(ts);
+
+        if (ts->tv_sec == (time_t) -1 &&
+            ts->tv_nsec == (long) -1)
+                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;
+}
+
+struct timespec *timespec_store(struct timespec *ts, usec_t u)  {
+        assert(ts);
+
+        if (u == USEC_INFINITY) {
+                ts->tv_sec = (time_t) -1;
+                ts->tv_nsec = (long) -1;
+                return ts;
+        }
+
+        ts->tv_sec = (time_t) (u / USEC_PER_SEC);
+        ts->tv_nsec = (long int) ((u % USEC_PER_SEC) * NSEC_PER_USEC);
+
+        return ts;
+}
+
+usec_t timeval_load(const struct timeval *tv) {
+        assert(tv);
+
+        if (tv->tv_sec == (time_t) -1 &&
+            tv->tv_usec == (suseconds_t) -1)
+                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) {
+                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;
+}
+
+static char *format_timestamp_internal(char *buf, size_t l, usec_t t, bool utc) {
+        struct tm tm;
+        time_t sec;
+
+        assert(buf);
+        assert(l > 0);
+
+        if (t <= 0 || t == USEC_INFINITY)
+                return NULL;
+
+        sec = (time_t) (t / USEC_PER_SEC);
+
+        if (utc)
+                gmtime_r(&sec, &tm);
+        else
+                localtime_r(&sec, &tm);
+        if (strftime(buf, l, "%a %Y-%m-%d %H:%M:%S %Z", &tm) <= 0)
+                return NULL;
+
+        return buf;
+}
+
+char *format_timestamp(char *buf, size_t l, usec_t t) {
+        return format_timestamp_internal(buf, l, t, false);
+}
+
+char *format_timestamp_utc(char *buf, size_t l, usec_t t) {
+        return format_timestamp_internal(buf, l, t, true);
+}
+
+static char *format_timestamp_internal_us(char *buf, size_t l, usec_t t, bool utc) {
+        struct tm tm;
+        time_t sec;
+
+        assert(buf);
+        assert(l > 0);
+
+        if (t <= 0 || t == USEC_INFINITY)
+                return NULL;
+
+        sec = (time_t) (t / USEC_PER_SEC);
+        if (utc)
+                gmtime_r(&sec, &tm);
+        else
+                localtime_r(&sec, &tm);
+
+        if (strftime(buf, l, "%a %Y-%m-%d %H:%M:%S", &tm) <= 0)
+                return NULL;
+        snprintf(buf + strlen(buf), l - strlen(buf), ".%06llu", (unsigned long long) (t % USEC_PER_SEC));
+        if (strftime(buf + strlen(buf), l - strlen(buf), " %Z", &tm) <= 0)
+                return NULL;
+
+        return buf;
+}
+
+char *format_timestamp_us(char *buf, size_t l, usec_t t) {
+        return format_timestamp_internal_us(buf, l, t, false);
+}
+
+char *format_timestamp_us_utc(char *buf, size_t l, usec_t t) {
+        return format_timestamp_internal_us(buf, l, t, true);
+}
+
+char *format_timestamp_relative(char *buf, size_t l, usec_t t) {
+        const char *s;
+        usec_t n, d;
+
+        if (t <= 0 || t == USEC_INFINITY)
+                return NULL;
+
+        n = now(CLOCK_REALTIME);
+        if (n > t) {
+                d = n - t;
+                s = "ago";
+        } else {
+                d = t - n;
+                s = "left";
+        }
+
+        if (d >= USEC_PER_YEAR)
+                snprintf(buf, l, USEC_FMT " years " USEC_FMT " months %s",
+                         d / USEC_PER_YEAR,
+                         (d % USEC_PER_YEAR) / USEC_PER_MONTH, s);
+        else if (d >= USEC_PER_MONTH)
+                snprintf(buf, l, USEC_FMT " months " USEC_FMT " days %s",
+                         d / USEC_PER_MONTH,
+                         (d % USEC_PER_MONTH) / USEC_PER_DAY, s);
+        else if (d >= USEC_PER_WEEK)
+                snprintf(buf, l, USEC_FMT " weeks " USEC_FMT " days %s",
+                         d / USEC_PER_WEEK,
+                         (d % USEC_PER_WEEK) / USEC_PER_DAY, s);
+        else if (d >= 2*USEC_PER_DAY)
+                snprintf(buf, l, USEC_FMT " days %s", d / USEC_PER_DAY, s);
+        else if (d >= 25*USEC_PER_HOUR)
+                snprintf(buf, l, "1 day " USEC_FMT "h %s",
+                         (d - USEC_PER_DAY) / USEC_PER_HOUR, s);
+        else if (d >= 6*USEC_PER_HOUR)
+                snprintf(buf, l, USEC_FMT "h %s",
+                         d / USEC_PER_HOUR, s);
+        else if (d >= USEC_PER_HOUR)
+                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)
+                snprintf(buf, l, USEC_FMT "min %s",
+                         d / USEC_PER_MINUTE, s);
+        else if (d >= USEC_PER_MINUTE)
+                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)
+                snprintf(buf, l, USEC_FMT "s %s",
+                         d / USEC_PER_SEC, s);
+        else if (d >= USEC_PER_MSEC)
+                snprintf(buf, l, USEC_FMT "ms %s",
+                         d / USEC_PER_MSEC, s);
+        else if (d > 0)
+                snprintf(buf, l, USEC_FMT"us %s",
+                         d, s);
+        else
+                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 },
+        };
+
+        unsigned i;
+        char *p = buf;
+        bool something = false;
+
+        assert(buf);
+        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 (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) {
+                        usec_t cc;
+                        int j;
+
+                        j = 0;
+                        for (cc = table[i].usec; cc > 1; cc /= 10)
+                                j++;
+
+                        for (cc = accuracy; cc > 1; cc /= 10) {
+                                b /= 10;
+                                j--;
+                        }
+
+                        if (j > 0) {
+                                k = snprintf(p, l,
+                                             "%s"USEC_FMT".%0*llu%s",
+                                             p > buf ? " " : "",
+                                             a,
+                                             j,
+                                             (unsigned long long) 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);
+
+                l -= n;
+                p += n;
+
+                something = true;
+        }
+
+        *p = 0;
+
+        return buf;
+}
+
+void dual_timestamp_serialize(FILE *f, const char *name, dual_timestamp *t) {
+
+        assert(f);
+        assert(name);
+        assert(t);
+
+        if (!dual_timestamp_is_set(t))
+                return;
+
+        fprintf(f, "%s="USEC_FMT" "USEC_FMT"\n",
+                name,
+                t->realtime,
+                t->monotonic);
+}
+
+int dual_timestamp_deserialize(const char *value, dual_timestamp *t) {
+        unsigned long long a, b;
+
+        assert(value);
+        assert(t);
+
+        if (sscanf(value, "%llu %llu", &a, &b) != 2) {
+                log_debug("Failed to parse finish timestamp value %s.", value);
+                return -EINVAL;
+        }
+
+        t->realtime = a;
+        t->monotonic = b;
+
+        return 0;
+}
+
+int parse_timestamp(const char *t, usec_t *usec) {
+        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 },
+        };
+
+        const char *k;
+        struct tm tm, copy;
+        time_t x;
+        usec_t plus = 0, minus = 0, ret;
+        int r, weekday = -1;
+        unsigned i;
+
+        /*
+         * Allowed syntaxes:
+         *
+         *   2012-09-22 16:34:22
+         *   2012-09-22 16:34     (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)
+         *
+         */
+
+        assert(t);
+        assert(usec);
+
+        x = time(NULL);
+        assert_se(localtime_r(&x, &tm));
+        tm.tm_isdst = -1;
+
+        if (streq(t, "now"))
+                goto finish;
+
+        else if (streq(t, "today")) {
+                tm.tm_sec = tm.tm_min = tm.tm_hour = 0;
+                goto finish;
+
+        } else if (streq(t, "yesterday")) {
+                tm.tm_mday --;
+                tm.tm_sec = tm.tm_min = tm.tm_hour = 0;
+                goto finish;
+
+        } else if (streq(t, "tomorrow")) {
+                tm.tm_mday ++;
+                tm.tm_sec = tm.tm_min = tm.tm_hour = 0;
+                goto finish;
+
+        } else if (t[0] == '+') {
+                r = parse_sec(t+1, &plus);
+                if (r < 0)
+                        return r;
+
+                goto finish;
+
+        } else if (t[0] == '-') {
+                r = parse_sec(t+1, &minus);
+                if (r < 0)
+                        return r;
+
+                goto finish;
+
+        } else if (t[0] == '@')
+                return parse_sec(t + 1, usec);
+
+        else if (endswith(t, " ago")) {
+                _cleanup_free_ char *z;
+
+                z = strndup(t, strlen(t) - 4);
+                if (!z)
+                        return -ENOMEM;
+
+                r = parse_sec(z, &minus);
+                if (r < 0)
+                        return r;
+
+                goto finish;
+        } else if (endswith(t, " left")) {
+                _cleanup_free_ char *z;
+
+                z = strndup(t, strlen(t) - 4);
+                if (!z)
+                        return -ENOMEM;
+
+                r = parse_sec(z, &plus);
+                if (r < 0)
+                        return r;
+
+                goto finish;
+        }
+
+        for (i = 0; i < ELEMENTSOF(day_nr); i++) {
+                size_t skip;
+
+                if (!startswith_no_case(t, day_nr[i].name))
+                        continue;
+
+                skip = strlen(day_nr[i].name);
+                if (t[skip] != ' ')
+                        continue;
+
+                weekday = day_nr[i].nr;
+                t += skip + 1;
+                break;
+        }
+
+        copy = tm;
+        k = strptime(t, "%y-%m-%d %H:%M:%S", &tm);
+        if (k && *k == 0)
+                goto finish;
+
+        tm = copy;
+        k = strptime(t, "%Y-%m-%d %H:%M:%S", &tm);
+        if (k && *k == 0)
+                goto finish;
+
+        tm = copy;
+        k = strptime(t, "%y-%m-%d %H:%M", &tm);
+        if (k && *k == 0) {
+                tm.tm_sec = 0;
+                goto finish;
+        }
+
+        tm = copy;
+        k = strptime(t, "%Y-%m-%d %H:%M", &tm);
+        if (k && *k == 0) {
+                tm.tm_sec = 0;
+                goto finish;
+        }
+
+        tm = copy;
+        k = strptime(t, "%y-%m-%d", &tm);
+        if (k && *k == 0) {
+                tm.tm_sec = tm.tm_min = tm.tm_hour = 0;
+                goto finish;
+        }
+
+        tm = copy;
+        k = strptime(t, "%Y-%m-%d", &tm);
+        if (k && *k == 0) {
+                tm.tm_sec = tm.tm_min = tm.tm_hour = 0;
+                goto finish;
+        }
+
+        tm = copy;
+        k = strptime(t, "%H:%M:%S", &tm);
+        if (k && *k == 0)
+                goto finish;
+
+        tm = copy;
+        k = strptime(t, "%H:%M", &tm);
+        if (k && *k == 0) {
+                tm.tm_sec = 0;
+                goto finish;
+        }
+
+        return -EINVAL;
+
+finish:
+        x = mktime(&tm);
+        if (x == (time_t) -1)
+                return -EINVAL;
+
+        if (weekday >= 0 && tm.tm_wday != weekday)
+                return -EINVAL;
+
+        ret = (usec_t) x * USEC_PER_SEC;
+
+        ret += plus;
+        if (ret > minus)
+                ret -= minus;
+        else
+                ret = 0;
+
+        *usec = ret;
+
+        return 0;
+}
+
+int parse_sec(const char *t, usec_t *usec) {
+        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 },
+                { "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 },
+                { "", USEC_PER_SEC }, /* default is sec */
+        };
+
+        const char *p, *s;
+        usec_t r = 0;
+        bool something = false;
+
+        assert(t);
+        assert(usec);
+
+        p = t;
+
+        p += strspn(p, WHITESPACE);
+        s = startswith(p, "infinity");
+        if (s) {
+                s += strspn(s, WHITESPACE);
+                if (*s != 0)
+                        return -EINVAL;
+
+                *usec = USEC_INFINITY;
+                return 0;
+        }
+
+        for (;;) {
+                long long l, z = 0;
+                char *e;
+                unsigned i, n = 0;
+
+                p += strspn(p, WHITESPACE);
+
+                if (*p == 0) {
+                        if (!something)
+                                return -EINVAL;
+
+                        break;
+                }
+
+                errno = 0;
+                l = strtoll(p, &e, 10);
+
+                if (errno > 0)
+                        return -errno;
+
+                if (l < 0)
+                        return -ERANGE;
+
+                if (*e == '.') {
+                        char *b = e + 1;
+
+                        errno = 0;
+                        z = strtoll(b, &e, 10);
+                        if (errno > 0)
+                                return -errno;
+
+                        if (z < 0)
+                                return -ERANGE;
+
+                        if (e == b)
+                                return -EINVAL;
+
+                        n = e - b;
+
+                } else if (e == p)
+                        return -EINVAL;
+
+                e += strspn(e, WHITESPACE);
+
+                for (i = 0; i < ELEMENTSOF(table); i++)
+                        if (startswith(e, table[i].suffix)) {
+                                usec_t k = (usec_t) z * table[i].usec;
+
+                                for (; n > 0; n--)
+                                        k /= 10;
+
+                                r += (usec_t) l * table[i].usec + k;
+                                p = e + strlen(table[i].suffix);
+
+                                something = true;
+                                break;
+                        }
+
+                if (i >= ELEMENTSOF(table))
+                        return -EINVAL;
+
+        }
+
+        *usec = r;
+
+        return 0;
+}
+
+int parse_nsec(const char *t, nsec_t *nsec) {
+        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 },
+                { "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 },
+                { "nsec", 1ULL },
+                { "ns", 1ULL },
+                { "", 1ULL }, /* default is nsec */
+        };
+
+        const char *p, *s;
+        nsec_t r = 0;
+        bool something = false;
+
+        assert(t);
+        assert(nsec);
+
+        p = t;
+
+        p += strspn(p, WHITESPACE);
+        s = startswith(p, "infinity");
+        if (s) {
+                s += strspn(s, WHITESPACE);
+                if (*s != 0)
+                        return -EINVAL;
+
+                *nsec = NSEC_INFINITY;
+                return 0;
+        }
+
+        for (;;) {
+                long long l, z = 0;
+                char *e;
+                unsigned i, n = 0;
+
+                p += strspn(p, WHITESPACE);
+
+                if (*p == 0) {
+                        if (!something)
+                                return -EINVAL;
+
+                        break;
+                }
+
+                errno = 0;
+                l = strtoll(p, &e, 10);
+
+                if (errno > 0)
+                        return -errno;
+
+                if (l < 0)
+                        return -ERANGE;
+
+                if (*e == '.') {
+                        char *b = e + 1;
+
+                        errno = 0;
+                        z = strtoll(b, &e, 10);
+                        if (errno > 0)
+                                return -errno;
+
+                        if (z < 0)
+                                return -ERANGE;
+
+                        if (e == b)
+                                return -EINVAL;
+
+                        n = e - b;
+
+                } else if (e == p)
+                        return -EINVAL;
+
+                e += strspn(e, WHITESPACE);
+
+                for (i = 0; i < ELEMENTSOF(table); i++)
+                        if (startswith(e, table[i].suffix)) {
+                                nsec_t k = (nsec_t) z * table[i].nsec;
+
+                                for (; n > 0; n--)
+                                        k /= 10;
+
+                                r += (nsec_t) l * table[i].nsec + k;
+                                p = e + strlen(table[i].suffix);
+
+                                something = true;
+                                break;
+                        }
+
+                if (i >= ELEMENTSOF(table))
+                        return -EINVAL;
+
+        }
+
+        *nsec = r;
+
+        return 0;
+}
+
+bool ntp_synced(void) {
+        struct timex txc = {};
+
+        if (adjtimex(&txc) < 0)
+                return false;
+
+        if (txc.status & STA_UNSYNC)
+                return false;
+
+        return true;
+}
+
+int get_timezones(char ***ret) {
+        _cleanup_fclose_ FILE *f = NULL;
+        _cleanup_strv_free_ char **zones = NULL;
+        size_t n_zones = 0, n_allocated = 0;
+
+        assert(ret);
+
+        zones = strv_new("UTC", NULL);
+        if (!zones)
+                return -ENOMEM;
+
+        n_allocated = 2;
+        n_zones = 1;
+
+        f = fopen("/usr/share/zoneinfo/zone.tab", "re");
+        if (f) {
+                char l[LINE_MAX];
+
+                FOREACH_LINE(l, f, return -errno) {
+                        char *p, *w;
+                        size_t k;
+
+                        p = strstrip(l);
+
+                        if (isempty(p) || *p == '#')
+                                continue;
+
+                        /* Skip over country code */
+                        p += strcspn(p, WHITESPACE);
+                        p += strspn(p, WHITESPACE);
+
+                        /* Skip over coordinates */
+                        p += strcspn(p, WHITESPACE);
+                        p += strspn(p, WHITESPACE);
+
+                        /* Found timezone name */
+                        k = strcspn(p, WHITESPACE);
+                        if (k <= 0)
+                                continue;
+
+                        w = strndup(p, k);
+                        if (!w)
+                                return -ENOMEM;
+
+                        if (!GREEDY_REALLOC(zones, n_allocated, n_zones + 2)) {
+                                free(w);
+                                return -ENOMEM;
+                        }
+
+                        zones[n_zones++] = w;
+                        zones[n_zones] = NULL;
+                }
+
+                strv_sort(zones);
+
+        } else if (errno != ENOENT)
+                return -errno;
+
+        *ret = zones;
+        zones = NULL;
+
+        return 0;
+}
+
+bool timezone_is_valid(const char *name) {
+        bool slash = false;
+        const char *p, *t;
+        struct stat st;
+
+        if (!name || *name == 0 || *name == '/')
+                return false;
+
+        for (p = name; *p; p++) {
+                if (!(*p >= '0' && *p <= '9') &&
+                    !(*p >= 'a' && *p <= 'z') &&
+                    !(*p >= 'A' && *p <= 'Z') &&
+                    !(*p == '-' || *p == '_' || *p == '+' || *p == '/'))
+                        return false;
+
+                if (*p == '/') {
+
+                        if (slash)
+                                return false;
+
+                        slash = true;
+                } else
+                        slash = false;
+        }
+
+        if (slash)
+                return false;
+
+        t = strjoina("/usr/share/zoneinfo/", name);
+        if (stat(t, &st) < 0)
+                return false;
+
+        if (!S_ISREG(st.st_mode))
+                return false;
+
+        return true;
+}
+
+clockid_t clock_boottime_or_monotonic(void) {
+        static clockid_t clock = -1;
+        int fd;
+
+        if (clock != -1)
+                return clock;
+
+        fd = timerfd_create(CLOCK_BOOTTIME, TFD_NONBLOCK|TFD_CLOEXEC);
+        if (fd < 0)
+                clock = CLOCK_MONOTONIC;
+        else {
+                safe_close(fd);
+                clock = CLOCK_BOOTTIME;
+        }
+
+        return clock;
+}