/* SPDX-License-Identifier: LGPL-2.1+ */
#include <alloca.h>
#include <ctype.h>
#include <errno.h>
#include <limits.h>
#include <stddef.h>
#include <stdio.h>
#include <stdio_ext.h>
#include <stdlib.h>
#include <string.h>
#include <sys/mman.h>
#include <time.h>
#include "alloc-util.h"
#include "calendarspec.h"
#include "fileio.h"
#include "macro.h"
#include "parse-util.h"
#include "process-util.h"
#include "string-util.h"
#include "time-util.h"
#define BITS_WEEKDAYS 127
#define MIN_YEAR 1970
#define MAX_YEAR 2199
/* An arbitrary limit on the length of the chains of components. We don't want to
* build a very long linked list, which would be slow to iterate over and might cause
* our stack to overflow. It's unlikely that legitimate uses require more than a few
* linked compenents anyway. */
#define CALENDARSPEC_COMPONENTS_MAX 240
static void free_chain(CalendarComponent *c) {
CalendarComponent *n;
while (c) {
n = c->next;
free(c);
c = n;
}
}
CalendarSpec* calendar_spec_free(CalendarSpec *c) {
if (!c)
return NULL;
free_chain(c->year);
free_chain(c->month);
free_chain(c->day);
free_chain(c->hour);
free_chain(c->minute);
free_chain(c->microsecond);
free(c->timezone);
return mfree(c);
}
static int component_compare(const void *_a, const void *_b) {
CalendarComponent * const *a = _a, * const *b = _b;
if ((*a)->start < (*b)->start)
return -1;
if ((*a)->start > (*b)->start)
return 1;
if ((*a)->stop < (*b)->stop)
return -1;
if ((*a)->stop > (*b)->stop)
return 1;
if ((*a)->repeat < (*b)->repeat)
return -1;
if ((*a)->repeat > (*b)->repeat)
return 1;
return 0;
}
static void normalize_chain(CalendarComponent **c) {
CalendarComponent **b, *i, **j, *next;
size_t n = 0, k;
assert(c);
for (i = *c; i; i = i->next) {
n++;
/*
* While we're counting the chain, also normalize `stop`
* so the length of the range is a multiple of `repeat`
*/
if (i->stop > i->start && i->repeat > 0)
i->stop -= (i->stop - i->start) % i->repeat;
}
if (n <= 1)
return;
j = b = newa(CalendarComponent*, n);
for (i = *c; i; i = i->next)
*(j++) = i;
qsort(b, n, sizeof(CalendarComponent*), component_compare);
b[n-1]->next = NULL;
next = b[n-1];
/* Drop non-unique entries */
for (k = n-1; k > 0; k--) {
if (component_compare(&b[k-1], &next) == 0) {
free(b[k-1]);
continue;
}
b[k-1]->next = next;
next = b[k-1];
}
*c = next;
}
static void fix_year(CalendarComponent *c) {
/* Turns 12 → 2012, 89 → 1989 */
while (c) {
if (c->start >= 0 && c->start < 70)
c->start += 2000;
if (c->stop >= 0 && c->stop < 70)
c->stop += 2000;
if (c->start >= 70 && c->start < 100)
c->start += 1900;
if (c->stop >= 70 && c->stop < 100)
c->stop += 1900;
c = c->next;
}
}
int calendar_spec_normalize(CalendarSpec *c) {
assert(c);
if (streq_ptr(c->timezone, "UTC")) {
c->utc = true;
c->timezone = mfree(c->timezone);
}
if (c->weekdays_bits <= 0 || c->weekdays_bits >= BITS_WEEKDAYS)
c->weekdays_bits = -1;
if (c->end_of_month && !c->day)
c->end_of_month = false;
fix_year(c->year);
normalize_chain(&c->year);
normalize_chain(&c->month);
normalize_chain(&c->day);
normalize_chain(&c->hour);
normalize_chain(&c->minute);
normalize_chain(&c->microsecond);
return 0;
}
_pure_ static bool chain_valid(CalendarComponent *c, int from, int to, bool end_of_month) {
assert(to >= from);
if (!c)
return true;
/* Forbid dates more than 28 days from the end of the month */
if (end_of_month)
to -= 3;
if (c->start < from || c->start > to)
return false;
/* Avoid overly large values that could cause overflow */
if (c->repeat > to - from)
return false;
/*
* c->repeat must be short enough so at least one repetition may
* occur before the end of the interval. For dates scheduled
* relative to the end of the month, c->start and c->stop
* correspond to the Nth last day of the month.
*/
if (c->stop >= 0) {
if (c->stop < from || c ->stop > to)
return false;
if (c->start + c->repeat > c->stop)
return false;
} else {
if (end_of_month && c->start - c->repeat < from)
return false;
if (!end_of_month && c->start + c->repeat > to)
return false;
}
if (c->next)
return chain_valid(c->next, from, to, end_of_month);
return true;
}
_pure_ bool calendar_spec_valid(CalendarSpec *c) {
assert(c);
if (c->weekdays_bits > BITS_WEEKDAYS)
return false;
if (!chain_valid(c->year, MIN_YEAR, MAX_YEAR, false))
return false;
if (!chain_valid(c->month, 1, 12, false))
return false;
if (!chain_valid(c->day, 1, 31, c->end_of_month))
return false;
if (!chain_valid(c->hour, 0, 23, false))
return false;
if (!chain_valid(c->minute, 0, 59, false))
return false;
if (!chain_valid(c->microsecond, 0, 60*USEC_PER_SEC-1, false))
return false;
return true;
}
static void format_weekdays(FILE *f, const CalendarSpec *c) {
static const char *const days[] = {
"Mon",
"Tue",
"Wed",
"Thu",
"Fri",
"Sat",
"Sun"
};
int l, x;
bool need_comma = false;
assert(f);
assert(c);
assert(c->weekdays_bits > 0 && c->weekdays_bits <= BITS_WEEKDAYS);
for (x = 0, l = -1; x < (int) ELEMENTSOF(days); x++) {
if (c->weekdays_bits & (1 << x)) {
if (l < 0) {
if (need_comma)
fputc(',', f);
else
need_comma = true;
fputs(days[x], f);
l = x;
}
} else if (l >= 0) {
if (x > l + 1) {
fputs(x > l + 2 ? ".." : ",", f);
fputs(days[x-1], f);
}
l = -1;
}
}
if (l >= 0 && x > l + 1) {
fputs(x > l + 2 ? ".." : ",", f);
fputs(days[x-1], f);
}
}
static void format_chain(FILE *f, int space, const CalendarComponent *c, bool usec) {
int d = usec ? (int) USEC_PER_SEC : 1;
assert(f);
if (!c) {
fputc('*', f);
return;
}
if (usec && c->start == 0 && c->repeat == USEC_PER_SEC && !c->next) {
fputc('*', f);
return;
}
assert(c->start >= 0);
fprintf(f, "%0*i", space, c->start / d);
if (c->start % d > 0)
fprintf(f, ".%06i", c->start % d);
if (c->stop > 0)
fprintf(f, "..%0*i", space, c->stop / d);
if (c->stop % d > 0)
fprintf(f, ".%06i", c->stop % d);
if (c->repeat > 0 && !(c->stop > 0 && c->repeat == d))
fprintf(f, "/%i", c->repeat / d);
if (c->repeat % d > 0)
fprintf(f, ".%06i", c->repeat % d);
if (c->next) {
fputc(',', f);
format_chain(f, space, c->next, usec);
}
}
int calendar_spec_to_string(const CalendarSpec *c, char **p) {
char *buf = NULL;
size_t sz = 0;
FILE *f;
int r;
assert(c);
assert(p);
f = open_memstream(&buf, &sz);
if (!f)
return -ENOMEM;
(void) __fsetlocking(f, FSETLOCKING_BYCALLER);
if (c->weekdays_bits > 0 && c->weekdays_bits <= BITS_WEEKDAYS) {
format_weekdays(f, c);
fputc(' ', f);
}
format_chain(f, 4, c->year, false);
fputc('-', f);
format_chain(f, 2, c->month, false);
fputc(c->end_of_month ? '~' : '-', f);
format_chain(f, 2, c->day, false);
fputc(' ', f);
format_chain(f, 2, c->hour, false);
fputc(':', f);
format_chain(f, 2, c->minute, false);
fputc(':', f);
format_chain(f, 2, c->microsecond, true);
if (c->utc)
fputs(" UTC", f);
else if (c->timezone != NULL) {
fputc(' ', f);
fputs(c->timezone, f);
} else if (IN_SET(c->dst, 0, 1)) {
/* If daylight saving is explicitly on or off, let's show the used timezone. */
tzset();
if (!isempty(tzname[c->dst])) {
fputc(' ', f);
fputs(tzname[c->dst], f);
}
}
r = fflush_and_check(f);
if (r < 0) {
free(buf);
fclose(f);
return r;
}
fclose(f);
*p = buf;
return 0;
}
static int parse_weekdays(const char **p, CalendarSpec *c) {
static const struct {
const char *name;
const int nr;
} day_nr[] = {
{ "Monday", 0 },
{ "Mon", 0 },
{ "Tuesday", 1 },
{ "Tue", 1 },
{ "Wednesday", 2 },
{ "Wed", 2 },
{ "Thursday", 3 },
{ "Thu", 3 },
{ "Friday", 4 },
{ "Fri", 4 },
{ "Saturday", 5 },
{ "Sat", 5 },
{ "Sunday", 6 },
{ "Sun", 6 }
};
int l = -1;
bool first = true;
assert(p);
assert(*p);
assert(c);
for (;;) {
size_t i;
for (i = 0; i < ELEMENTSOF(day_nr); i++) {
size_t skip;
if (!startswith_no_case(*p, day_nr[i].name))
continue;
skip = strlen(day_nr[i].name);
if (!IN_SET((*p)[skip], 0, '-', '.', ',', ' '))
return -EINVAL;
c->weekdays_bits |= 1 << day_nr[i].nr;
if (l >= 0) {
int j;
if (l > day_nr[i].nr)
return -EINVAL;
for (j = l + 1; j < day_nr[i].nr; j++)
c->weekdays_bits |= 1 << j;
}
*p += skip;
break;
}
/* Couldn't find this prefix, so let's assume the
weekday was not specified and let's continue with
the date */
if (i >= ELEMENTSOF(day_nr))
return first ? 0 : -EINVAL;
/* We reached the end of the string */
if (**p == 0)
return 0;
/* We reached the end of the weekday spec part */
if (**p == ' ') {
*p += strspn(*p, " ");
return 0;
}
if (**p == '.') {
if (l >= 0)
return -EINVAL;
if ((*p)[1] != '.')
return -EINVAL;
l = day_nr[i].nr;
*p += 2;
/* Support ranges with "-" for backwards compatibility */
} else if (**p == '-') {
if (l >= 0)
return -EINVAL;
l = day_nr[i].nr;
*p += 1;
} else if (**p == ',') {
l = -1;
*p += 1;
}
/* Allow a trailing comma but not an open range */
if (IN_SET(**p, 0, ' ')) {
*p += strspn(*p, " ");
return l < 0 ? 0 : -EINVAL;
}
first = false;
}
}
static int parse_one_number(const char *p, const char **e, unsigned long *ret) {
char *ee = NULL;
unsigned long value;
errno = 0;
value = strtoul(p, &ee, 10);
if (errno > 0)
return -errno;
if (ee == p)
return -EINVAL;
*ret = value;
*e = ee;
return 0;
}
static int parse_component_decimal(const char **p, bool usec, int *res) {
unsigned long value;
const char *e = NULL;
int r;
if (!isdigit(**p))
return -EINVAL;
r = parse_one_number(*p, &e, &value);
if (r < 0)
return r;
if (usec) {
if (value * USEC_PER_SEC / USEC_PER_SEC != value)
return -ERANGE;
value *= USEC_PER_SEC;
/* One "." is a decimal point, but ".." is a range separator */
if (e[0] == '.' && e[1] != '.') {
unsigned add;
e++;
r = parse_fractional_part_u(&e, 6, &add);
if (r < 0)
return r;
if (add + value < value)
return -ERANGE;
value += add;
}
}
if (value > INT_MAX)
return -ERANGE;
*p = e;
*res = value;
return 0;
}
static int const_chain(int value, CalendarComponent **c) {
CalendarComponent *cc = NULL;
assert(c);
cc = new0(CalendarComponent, 1);
if (!cc)
return -ENOMEM;
cc->start = value;
cc->stop = -1;
cc->repeat = 0;
cc->next = *c;
*c = cc;
return 0;
}
static int calendarspec_from_time_t(CalendarSpec *c, time_t time) {
struct tm tm;
CalendarComponent *year = NULL, *month = NULL, *day = NULL, *hour = NULL, *minute = NULL, *us = NULL;
int r;
if (!gmtime_r(&time, &tm))
return -ERANGE;
r = const_chain(tm.tm_year + 1900, &year);
if (r < 0)
return r;
r = const_chain(tm.tm_mon + 1, &month);
if (r < 0)
return r;
r = const_chain(tm.tm_mday, &day);
if (r < 0)
return r;
r = const_chain(tm.tm_hour, &hour);
if (r < 0)
return r;
r = const_chain(tm.tm_min, &minute);
if (r < 0)
return r;
r = const_chain(tm.tm_sec * USEC_PER_SEC, &us);
if (r < 0)
return r;
c->utc = true;
c->year = year;
c->month = month;
c->day = day;
c->hour = hour;
c->minute = minute;
c->microsecond = us;
return 0;
}
static int prepend_component(const char **p, bool usec, unsigned nesting, CalendarComponent **c) {
int r, start, stop = -1, repeat = 0;
CalendarComponent *cc;
const char *e = *p;
assert(p);
assert(c);
if (nesting > CALENDARSPEC_COMPONENTS_MAX)
return -ENOBUFS;
r = parse_component_decimal(&e, usec, &start);
if (r < 0)
return r;
if (e[0] == '.' && e[1] == '.') {
e += 2;
r = parse_component_decimal(&e, usec, &stop);
if (r < 0)
return r;
repeat = usec ? USEC_PER_SEC : 1;
}
if (*e == '/') {
e++;
r = parse_component_decimal(&e, usec, &repeat);
if (r < 0)
return r;
if (repeat == 0)
return -ERANGE;
}
if (!IN_SET(*e, 0, ' ', ',', '-', '~', ':'))
return -EINVAL;
cc = new0(CalendarComponent, 1);
if (!cc)
return -ENOMEM;
cc->start = start;
cc->stop = stop;
cc->repeat = repeat;
cc->next = *c;
*p = e;
*c = cc;
if (*e ==',') {
*p += 1;
return prepend_component(p, usec, nesting + 1, c);
}
return 0;
}
static int parse_chain(const char **p, bool usec, CalendarComponent **c) {
const char *t;
CalendarComponent *cc = NULL;
int r;
assert(p);
assert(c);
t = *p;
if (t[0] == '*') {
if (usec) {
r = const_chain(0, c);
if (r < 0)
return r;
(*c)->repeat = USEC_PER_SEC;
} else
*c = NULL;
*p = t + 1;
return 0;
}
r = prepend_component(&t, usec, 0, &cc);
if (r < 0) {
free_chain(cc);
return r;
}
*p = t;
*c = cc;
return 0;
}
static int parse_date(const char **p, CalendarSpec *c) {
const char *t;
int r;
CalendarComponent *first, *second, *third;
assert(p);
assert(*p);
assert(c);
t = *p;
if (*t == 0)
return 0;
/* @TIMESTAMP — UNIX time in seconds since the epoch */
if (*t == '@') {
unsigned long value;
time_t time;
r = parse_one_number(t + 1, &t, &value);
if (r < 0)
return r;
time = value;
if ((unsigned long) time != value)
return -ERANGE;
r = calendarspec_from_time_t(c, time);
if (r < 0)
return r;
*p = t;
return 1; /* finito, don't parse H:M:S after that */
}
r = parse_chain(&t, false, &first);
if (r < 0)
return r;
/* Already the end? A ':' as separator? In that case this was a time, not a date */
if (IN_SET(*t, 0, ':')) {
free_chain(first);
return 0;
}
if (*t == '~')
c->end_of_month = true;
else if (*t != '-') {
free_chain(first);
return -EINVAL;
}
t++;
r = parse_chain(&t, false, &second);
if (r < 0) {
free_chain(first);
return r;
}
/* Got two parts, hence it's month and day */
if (IN_SET(*t, 0, ' ')) {
*p = t + strspn(t, " ");
c->month = first;
c->day = second;
return 0;
} else if (c->end_of_month) {
free_chain(first);
free_chain(second);
return -EINVAL;
}
if (*t == '~')
c->end_of_month = true;
else if (*t != '-') {
free_chain(first);
free_chain(second);
return -EINVAL;
}
t++;
r = parse_chain(&t, false, &third);
if (r < 0) {
free_chain(first);
free_chain(second);
return r;
}
/* Got three parts, hence it is year, month and day */
if (IN_SET(*t, 0, ' ')) {
*p = t + strspn(t, " ");
c->year = first;
c->month = second;
c->day = third;
return 0;
}
free_chain(first);
free_chain(second);
free_chain(third);
return -EINVAL;
}
static int parse_calendar_time(const char **p, CalendarSpec *c) {
CalendarComponent *h = NULL, *m = NULL, *s = NULL;
const char *t;
int r;
assert(p);
assert(*p);
assert(c);
t = *p;
/* If no time is specified at all, then this means 00:00:00 */
if (*t == 0)
goto null_hour;
r = parse_chain(&t, false, &h);
if (r < 0)
goto fail;
if (*t != ':') {
r = -EINVAL;
goto fail;
}
t++;
r = parse_chain(&t, false, &m);
if (r < 0)
goto fail;
/* Already at the end? Then it's hours and minutes, and seconds are 0 */
if (*t == 0)
goto null_second;
if (*t != ':') {
r = -EINVAL;
goto fail;
}
t++;
r = parse_chain(&t, true, &s);
if (r < 0)
goto fail;
/* At the end? Then it's hours, minutes and seconds */
if (*t == 0)
goto finish;
r = -EINVAL;
goto fail;
null_hour:
r = const_chain(0, &h);
if (r < 0)
goto fail;
r = const_chain(0, &m);
if (r < 0)
goto fail;
null_second:
r = const_chain(0, &s);
if (r < 0)
goto fail;
finish:
*p = t;
c->hour = h;
c->minute = m;
c->microsecond = s;
return 0;
fail:
free_chain(h);
free_chain(m);
free_chain(s);
return r;
}
int calendar_spec_from_string(const char *p, CalendarSpec **spec) {
const char *utc;
_cleanup_(calendar_spec_freep) CalendarSpec *c = NULL;
int r;
assert(p);
assert(spec);
c = new0(CalendarSpec, 1);
if (!c)
return -ENOMEM;
c->dst = -1;
c->timezone = NULL;
utc = endswith_no_case(p, " UTC");
if (utc) {
c->utc = true;
p = strndupa(p, utc - p);
} else {
const char *e = NULL;
int j;
tzset();
/* Check if the local timezone was specified? */
for (j = 0; j <= 1; j++) {
if (isempty(tzname[j]))
continue;
e = endswith_no_case(p, tzname[j]);
if (!e)
continue;
if (e == p)
continue;
if (e[-1] != ' ')
continue;
break;
}
/* Found one of the two timezones specified? */
if (IN_SET(j, 0, 1)) {
p = strndupa(p, e - p - 1);
c->dst = j;
} else {
const char *last_space;
last_space = strrchr(p, ' ');
if (last_space != NULL && timezone_is_valid(last_space + 1, LOG_DEBUG)) {
c->timezone = strdup(last_space + 1);
if (!c->timezone)
return -ENOMEM;
p = strndupa(p, last_space - p);
}
}
}
if (isempty(p))
return -EINVAL;
if (strcaseeq(p, "minutely")) {
r = const_chain(0, &c->microsecond);
if (r < 0)
return r;
} else if (strcaseeq(p, "hourly")) {
r = const_chain(0, &c->minute);
if (r < 0)
return r;
r = const_chain(0, &c->microsecond);
if (r < 0)
return r;
} else if (strcaseeq(p, "daily")) {
r = const_chain(0, &c->hour);
if (r < 0)
return r;
r = const_chain(0, &c->minute);
if (r < 0)
return r;
r = const_chain(0, &c->microsecond);
if (r < 0)
return r;
} else if (strcaseeq(p, "monthly")) {
r = const_chain(1, &c->day);
if (r < 0)
return r;
r = const_chain(0, &c->hour);
if (r < 0)
return r;
r = const_chain(0, &c->minute);
if (r < 0)
return r;
r = const_chain(0, &c->microsecond);
if (r < 0)
return r;
} else if (strcaseeq(p, "annually") ||
strcaseeq(p, "yearly") ||
strcaseeq(p, "anually") /* backwards compatibility */ ) {
r = const_chain(1, &c->month);
if (r < 0)
return r;
r = const_chain(1, &c->day);
if (r < 0)
return r;
r = const_chain(0, &c->hour);
if (r < 0)
return r;
r = const_chain(0, &c->minute);
if (r < 0)
return r;
r = const_chain(0, &c->microsecond);
if (r < 0)
return r;
} else if (strcaseeq(p, "weekly")) {
c->weekdays_bits = 1;
r = const_chain(0, &c->hour);
if (r < 0)
return r;
r = const_chain(0, &c->minute);
if (r < 0)
return r;
r = const_chain(0, &c->microsecond);
if (r < 0)
return r;
} else if (strcaseeq(p, "quarterly")) {
r = const_chain(1, &c->month);
if (r < 0)
return r;
r = const_chain(4, &c->month);
if (r < 0)
return r;
r = const_chain(7, &c->month);
if (r < 0)
return r;
r = const_chain(10, &c->month);
if (r < 0)
return r;
r = const_chain(1, &c->day);
if (r < 0)
return r;
r = const_chain(0, &c->hour);
if (r < 0)
return r;
r = const_chain(0, &c->minute);
if (r < 0)
return r;
r = const_chain(0, &c->microsecond);
if (r < 0)
return r;
} else if (strcaseeq(p, "biannually") ||
strcaseeq(p, "bi-annually") ||
strcaseeq(p, "semiannually") ||
strcaseeq(p, "semi-annually")) {
r = const_chain(1, &c->month);
if (r < 0)
return r;
r = const_chain(7, &c->month);
if (r < 0)
return r;
r = const_chain(1, &c->day);
if (r < 0)
return r;
r = const_chain(0, &c->hour);
if (r < 0)
return r;
r = const_chain(0, &c->minute);
if (r < 0)
return r;
r = const_chain(0, &c->microsecond);
if (r < 0)
return r;
} else {
r = parse_weekdays(&p, c);
if (r < 0)
return r;
r = parse_date(&p, c);
if (r < 0)
return r;
if (r == 0) {
r = parse_calendar_time(&p, c);
if (r < 0)
return r;
}
if (*p != 0)
return -EINVAL;
}
r = calendar_spec_normalize(c);
if (r < 0)
return r;
if (!calendar_spec_valid(c))
return -EINVAL;
*spec = TAKE_PTR(c);
return 0;
}
static int find_end_of_month(struct tm *tm, bool utc, int day) {
struct tm t = *tm;
t.tm_mon++;
t.tm_mday = 1 - day;
if (mktime_or_timegm(&t, utc) < 0 ||
t.tm_mon != tm->tm_mon)
return -1;
return t.tm_mday;
}
static int find_matching_component(const CalendarSpec *spec, const CalendarComponent *c,
struct tm *tm, int *val) {
const CalendarComponent *p = c;
int start, stop, d = -1;
bool d_set = false;
int r;
assert(val);
if (!c)
return 0;
while (c) {
start = c->start;
stop = c->stop;
if (spec->end_of_month && p == spec->day) {
start = find_end_of_month(tm, spec->utc, start);
stop = find_end_of_month(tm, spec->utc, stop);
if (stop > 0)
SWAP_TWO(start, stop);
}
if (start >= *val) {
if (!d_set || start < d) {
d = start;
d_set = true;
}
} else if (c->repeat > 0) {
int k;
k = start + c->repeat * DIV_ROUND_UP(*val - start, c->repeat);
if ((!d_set || k < d) && (stop < 0 || k <= stop)) {
d = k;
d_set = true;
}
}
c = c->next;
}
if (!d_set)
return -ENOENT;
r = *val != d;
*val = d;
return r;
}
static bool tm_out_of_bounds(const struct tm *tm, bool utc) {
struct tm t;
assert(tm);
t = *tm;
if (mktime_or_timegm(&t, utc) < 0)
return true;
/*
* Set an upper bound on the year so impossible dates like "*-02-31"
* don't cause find_next() to loop forever. tm_year contains years
* since 1900, so adjust it accordingly.
*/
if (tm->tm_year + 1900 > MAX_YEAR)
return true;
/* Did any normalization take place? If so, it was out of bounds before */
return
t.tm_year != tm->tm_year ||
t.tm_mon != tm->tm_mon ||
t.tm_mday != tm->tm_mday ||
t.tm_hour != tm->tm_hour ||
t.tm_min != tm->tm_min ||
t.tm_sec != tm->tm_sec;
}
static bool matches_weekday(int weekdays_bits, const struct tm *tm, bool utc) {
struct tm t;
int k;
if (weekdays_bits < 0 || weekdays_bits >= BITS_WEEKDAYS)
return true;
t = *tm;
if (mktime_or_timegm(&t, utc) < 0)
return false;
k = t.tm_wday == 0 ? 6 : t.tm_wday - 1;
return (weekdays_bits & (1 << k));
}
static int find_next(const CalendarSpec *spec, struct tm *tm, usec_t *usec) {
struct tm c;
int tm_usec;
int r;
assert(spec);
assert(tm);
c = *tm;
tm_usec = *usec;
for (;;) {
/* Normalize the current date */
(void) mktime_or_timegm(&c, spec->utc);
c.tm_isdst = spec->dst;
c.tm_year += 1900;
r = find_matching_component(spec, spec->year, &c, &c.tm_year);
c.tm_year -= 1900;
if (r > 0) {
c.tm_mon = 0;
c.tm_mday = 1;
c.tm_hour = c.tm_min = c.tm_sec = tm_usec = 0;
}
if (r < 0)
return r;
if (tm_out_of_bounds(&c, spec->utc))
return -ENOENT;
c.tm_mon += 1;
r = find_matching_component(spec, spec->month, &c, &c.tm_mon);
c.tm_mon -= 1;
if (r > 0) {
c.tm_mday = 1;
c.tm_hour = c.tm_min = c.tm_sec = tm_usec = 0;
}
if (r < 0 || tm_out_of_bounds(&c, spec->utc)) {
c.tm_year++;
c.tm_mon = 0;
c.tm_mday = 1;
c.tm_hour = c.tm_min = c.tm_sec = tm_usec = 0;
continue;
}
r = find_matching_component(spec, spec->day, &c, &c.tm_mday);
if (r > 0)
c.tm_hour = c.tm_min = c.tm_sec = tm_usec = 0;
if (r < 0 || tm_out_of_bounds(&c, spec->utc)) {
c.tm_mon++;
c.tm_mday = 1;
c.tm_hour = c.tm_min = c.tm_sec = tm_usec = 0;
continue;
}
if (!matches_weekday(spec->weekdays_bits, &c, spec->utc)) {
c.tm_mday++;
c.tm_hour = c.tm_min = c.tm_sec = tm_usec = 0;
continue;
}
r = find_matching_component(spec, spec->hour, &c, &c.tm_hour);
if (r > 0)
c.tm_min = c.tm_sec = tm_usec = 0;
if (r < 0 || tm_out_of_bounds(&c, spec->utc)) {
c.tm_mday++;
c.tm_hour = c.tm_min = c.tm_sec = tm_usec = 0;
continue;
}
r = find_matching_component(spec, spec->minute, &c, &c.tm_min);
if (r > 0)
c.tm_sec = tm_usec = 0;
if (r < 0 || tm_out_of_bounds(&c, spec->utc)) {
c.tm_hour++;
c.tm_min = c.tm_sec = tm_usec = 0;
continue;
}
c.tm_sec = c.tm_sec * USEC_PER_SEC + tm_usec;
r = find_matching_component(spec, spec->microsecond, &c, &c.tm_sec);
tm_usec = c.tm_sec % USEC_PER_SEC;
c.tm_sec /= USEC_PER_SEC;
if (r < 0 || tm_out_of_bounds(&c, spec->utc)) {
c.tm_min++;
c.tm_sec = tm_usec = 0;
continue;
}
*tm = c;
*usec = tm_usec;
return 0;
}
}
static int calendar_spec_next_usec_impl(const CalendarSpec *spec, usec_t usec, usec_t *next) {
struct tm tm;
time_t t;
int r;
usec_t tm_usec;
assert(spec);
assert(next);
if (usec > USEC_TIMESTAMP_FORMATTABLE_MAX)
return -EINVAL;
usec++;
t = (time_t) (usec / USEC_PER_SEC);
assert_se(localtime_or_gmtime_r(&t, &tm, spec->utc));
tm_usec = usec % USEC_PER_SEC;
r = find_next(spec, &tm, &tm_usec);
if (r < 0)
return r;
t = mktime_or_timegm(&tm, spec->utc);
if (t < 0)
return -EINVAL;
*next = (usec_t) t * USEC_PER_SEC + tm_usec;
return 0;
}
typedef struct SpecNextResult {
usec_t next;
int return_value;
} SpecNextResult;
int calendar_spec_next_usec(const CalendarSpec *spec, usec_t usec, usec_t *next) {
SpecNextResult *shared, tmp;
int r;
if (isempty(spec->timezone))
return calendar_spec_next_usec_impl(spec, usec, next);
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-calendar)", FORK_RESET_SIGNALS|FORK_CLOSE_ALL_FDS|FORK_DEATHSIG|FORK_WAIT, NULL);
if (r < 0) {
(void) munmap(shared, sizeof *shared);
return r;
}
if (r == 0) {
if (setenv("TZ", spec->timezone, 1) != 0) {
shared->return_value = negative_errno();
_exit(EXIT_FAILURE);
}
tzset();
shared->return_value = calendar_spec_next_usec_impl(spec, usec, &shared->next);
_exit(EXIT_SUCCESS);
}
tmp = *shared;
if (munmap(shared, sizeof *shared) < 0)
return negative_errno();
if (tmp.return_value == 0)
*next = tmp.next;
return tmp.return_value;
}