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authorLennart Poettering <lennart@poettering.net>2012-11-23 21:37:58 +0100
committerLennart Poettering <lennart@poettering.net>2012-11-23 21:37:58 +0100
commit36697dc0199e25f09b78090fcf5f1cf8a3648ffd (patch)
tree7caef3bc1761327c366fc4a93a138e53fc692712 /src/shared/calendarspec.c
parent8a1175118e7a2e60a6ec42624f915e26e821f4e8 (diff)
timer: implement calendar time events
Diffstat (limited to 'src/shared/calendarspec.c')
-rw-r--r--src/shared/calendarspec.c927
1 files changed, 927 insertions, 0 deletions
diff --git a/src/shared/calendarspec.c b/src/shared/calendarspec.c
new file mode 100644
index 0000000000..3cddb0eed0
--- /dev/null
+++ b/src/shared/calendarspec.c
@@ -0,0 +1,927 @@
+/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
+
+/***
+ This file is part of systemd.
+
+ Copyright 2012 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 <stdlib.h>
+#include <string.h>
+
+#include "calendarspec.h"
+
+static void free_chain(CalendarComponent *c) {
+ CalendarComponent *n;
+
+ while (c) {
+ n = c->next;
+ free(c);
+ c = n;
+ }
+}
+
+void calendar_spec_free(CalendarSpec *c) {
+ assert(c);
+
+ free_chain(c->year);
+ free_chain(c->month);
+ free_chain(c->day);
+ free_chain(c->hour);
+ free_chain(c->minute);
+ free_chain(c->second);
+
+ free(c);
+}
+
+static int component_compare(const void *_a, const void *_b) {
+ CalendarComponent * const *a = _a, * const *b = _b;
+
+ if ((*a)->value < (*b)->value)
+ return -1;
+ if ((*a)->value > (*b)->value)
+ return 1;
+
+ if ((*a)->repeat < (*b)->repeat)
+ return -1;
+ if ((*a)->repeat > (*b)->repeat)
+ return 1;
+
+ return 0;
+}
+
+static void sort_chain(CalendarComponent **c) {
+ unsigned n = 0, k;
+ CalendarComponent **b, *i, **j, *next;
+
+ assert(c);
+
+ for (i = *c; i; i = i->next)
+ n++;
+
+ if (n <= 1)
+ return;
+
+ j = b = alloca(sizeof(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 (b[k-1]->value == next->value &&
+ b[k-1]->repeat == next->repeat) {
+ 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) {
+ CalendarComponent *n = c->next;
+
+ if (c->value >= 0 && c->value < 70)
+ c->value += 2000;
+
+ if (c->value >= 70 && c->value < 100)
+ c->value += 1900;
+
+ c = n;
+ }
+}
+
+int calendar_spec_normalize(CalendarSpec *c) {
+ assert(c);
+
+ if (c->weekdays_bits <= 0 || c->weekdays_bits >= 127)
+ c->weekdays_bits = -1;
+
+ fix_year(c->year);
+
+ sort_chain(&c->year);
+ sort_chain(&c->month);
+ sort_chain(&c->day);
+ sort_chain(&c->hour);
+ sort_chain(&c->minute);
+ sort_chain(&c->second);
+
+ return 0;
+}
+
+static bool chain_valid(CalendarComponent *c, int from, int to) {
+ if (!c)
+ return true;
+
+ if (c->value < from || c->value > to)
+ return false;
+
+ if (c->value + c->repeat > to)
+ return false;
+
+ if (c->next)
+ return chain_valid(c->next, from, to);
+
+ return true;
+}
+
+bool calendar_spec_valid(CalendarSpec *c) {
+ assert(c);
+
+ if (c->weekdays_bits > 127)
+ return false;
+
+ if (!chain_valid(c->year, 1970, 2199))
+ return false;
+
+ if (!chain_valid(c->month, 1, 12))
+ return false;
+
+ if (!chain_valid(c->day, 1, 31))
+ return false;
+
+ if (!chain_valid(c->hour, 0, 23))
+ return false;
+
+ if (!chain_valid(c->minute, 0, 59))
+ return false;
+
+ if (!chain_valid(c->second, 0, 59))
+ 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_colon = false;
+
+ assert(f);
+ assert(c);
+ assert(c->weekdays_bits > 0 && c->weekdays_bits <= 127);
+
+ for (x = 0, l = -1; x < (int) ELEMENTSOF(days); x++) {
+
+ if (c->weekdays_bits & (1 << x)) {
+
+ if (l < 0) {
+ if (need_colon)
+ fputc(',', f);
+ else
+ need_colon = true;
+
+ fputs(days[x], f);
+ l = x;
+ }
+
+ } else if (l >= 0) {
+
+ if (x > l + 1) {
+ fputc(x > l + 2 ? '-' : ',', f);
+ fputs(days[x-1], f);
+ }
+
+ l = -1;
+ }
+ }
+
+ if (l >= 0 && x > l + 1) {
+ fputc(x > l + 2 ? '-' : ',', f);
+ fputs(days[x-1], f);
+ }
+}
+
+static void format_chain(FILE *f, int space, const CalendarComponent *c) {
+ assert(f);
+
+ if (!c) {
+ fputc('*', f);
+ return;
+ }
+
+ assert(c->value >= 0);
+ fprintf(f, "%0*i", space, c->value);
+
+ if (c->repeat > 0)
+ fprintf(f, "/%i", c->repeat);
+
+ if (c->next) {
+ fputc(',', f);
+ format_chain(f, space, c->next);
+ }
+}
+
+int calendar_spec_to_string(const CalendarSpec *c, char **p) {
+ char *buf = NULL;
+ size_t sz = 0;
+ FILE *f;
+
+ assert(c);
+ assert(p);
+
+ f = open_memstream(&buf, &sz);
+ if (!f)
+ return -ENOMEM;
+
+ if (c->weekdays_bits > 0 && c->weekdays_bits <= 127) {
+ format_weekdays(f, c);
+ fputc(' ', f);
+ }
+
+ format_chain(f, 4, c->year);
+ fputc('-', f);
+ format_chain(f, 2, c->month);
+ fputc('-', f);
+ format_chain(f, 2, c->day);
+ fputc(' ', f);
+ format_chain(f, 2, c->hour);
+ fputc(':', f);
+ format_chain(f, 2, c->minute);
+ fputc(':', f);
+ format_chain(f, 2, c->second);
+
+ fflush(f);
+
+ if (ferror(f)) {
+ free(buf);
+ fclose(f);
+ return -ENOMEM;
+ }
+
+ 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 (;;) {
+ unsigned i;
+
+ if (!first && **p == ' ')
+ return 0;
+
+ 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 ((*p)[skip] != '-' &&
+ (*p)[skip] != ',' &&
+ (*p)[skip] != ' ' &&
+ (*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;
+
+ l = day_nr[i].nr;
+ } else
+ l = -1;
+
+ *p += 1;
+ first = false;
+ }
+}
+
+static int prepend_component(const char **p, CalendarComponent **c) {
+ unsigned long value, repeat = 0;
+ char *e = NULL, *ee = NULL;
+ CalendarComponent *cc;
+
+ assert(p);
+ assert(c);
+
+ errno = 0;
+ value = strtoul(*p, &e, 10);
+ if (errno != 0)
+ return -errno;
+ if (e == *p)
+ return -EINVAL;
+ if ((unsigned long) (int) value != value)
+ return -ERANGE;
+
+ if (*e == '/') {
+ repeat = strtoul(e+1, &ee, 10);
+ if (errno != 0)
+ return -errno;
+ if (ee == e+1)
+ return -EINVAL;
+ if ((unsigned long) (int) repeat != repeat)
+ return -ERANGE;
+ if (repeat <= 0)
+ return -ERANGE;
+
+ e = ee;
+ }
+
+ if (*e != 0 && *e != ' ' && *e != ',' && *e != '-' && *e != ':')
+ return -EINVAL;
+
+ cc = new0(CalendarComponent, 1);
+ if (!cc)
+ return -ENOMEM;
+
+ cc->value = value;
+ cc->repeat = repeat;
+ cc->next = *c;
+
+ *p = e;
+ *c = cc;
+
+ if (*e ==',') {
+ *p += 1;
+ return prepend_component(p, c);
+ }
+
+ return 0;
+}
+
+static int parse_chain(const char **p, CalendarComponent **c) {
+ const char *t;
+ CalendarComponent *cc = NULL;
+ int r;
+
+ assert(p);
+ assert(c);
+
+ t = *p;
+
+ if (t[0] == '*') {
+ *p = t + 1;
+ *c = NULL;
+ return 0;
+ }
+
+ r = prepend_component(&t, &cc);
+ if (r < 0) {
+ free_chain(cc);
+ return r;
+ }
+
+ *p = t;
+ *c = cc;
+ return 0;
+}
+
+static int const_chain(int value, CalendarComponent **c) {
+ CalendarComponent *cc = NULL;
+
+ assert(c);
+
+ cc = new0(CalendarComponent, 1);
+ if (!cc)
+ return -ENOMEM;
+
+ cc->value = value;
+ cc->repeat = 0;
+ cc->next = NULL;
+
+ *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;
+
+ r = parse_chain(&t, &first);
+ if (r < 0)
+ return r;
+
+ /* Already the end? A ':' as separator? In that case this was a time, not a date */
+ if (*t == 0 || *t == ':') {
+ free_chain(first);
+ return 0;
+ }
+
+ if (*t != '-') {
+ free_chain(first);
+ return -EINVAL;
+ }
+
+ t++;
+ r = parse_chain(&t, &second);
+ if (r < 0) {
+ free_chain(first);
+ return r;
+ }
+
+ /* Got two parts, hence it's month and day */
+ if (*t == ' ' || *t == 0) {
+ *p = t + strspn(t, " ");
+ c->month = first;
+ c->day = second;
+ return 0;
+ }
+
+ if (*t != '-') {
+ free_chain(first);
+ free_chain(second);
+ return -EINVAL;
+ }
+
+ t++;
+ r = parse_chain(&t, &third);
+ if (r < 0) {
+ free_chain(first);
+ free_chain(second);
+ return r;
+ }
+
+ /* Got tree parts, hence it is year, month and day */
+ if (*t == ' ' || *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_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 (*t == 0) {
+ /* If no time is specified at all, but a date of some
+ * kind, then this means 00:00:00 */
+ if (c->day || c->weekdays_bits > 0)
+ goto null_hour;
+
+ goto finish;
+ }
+
+ r = parse_chain(&t, &h);
+ if (r < 0)
+ goto fail;
+
+ if (*t != ':') {
+ r = -EINVAL;
+ goto fail;
+ }
+
+ t++;
+ r = parse_chain(&t, &m);
+ if (r < 0)
+ goto fail;
+
+ /* Already at the end? Then it's hours and minutes, and seconds are 0 */
+ if (*t == 0) {
+ if (m != NULL)
+ goto null_second;
+
+ goto finish;
+ }
+
+ if (*t != ':') {
+ r = -EINVAL;
+ goto fail;
+ }
+
+ t++;
+ r = parse_chain(&t, &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->second = 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) {
+ CalendarSpec *c;
+ int r;
+
+ assert(p);
+ assert(spec);
+
+ if (isempty(p))
+ return -EINVAL;
+
+ c = new0(CalendarSpec, 1);
+ if (!c)
+ return -ENOMEM;
+
+ if (strcasecmp(p, "hourly") == 0) {
+ r = const_chain(0, &c->minute);
+ if (r < 0)
+ goto fail;
+ r = const_chain(0, &c->second);
+ if (r < 0)
+ goto fail;
+
+ } else if (strcasecmp(p, "daily") == 0) {
+ r = const_chain(0, &c->hour);
+ if (r < 0)
+ goto fail;
+ r = const_chain(0, &c->minute);
+ if (r < 0)
+ goto fail;
+ r = const_chain(0, &c->second);
+ if (r < 0)
+ goto fail;
+
+ } else if (strcasecmp(p, "monthly") == 0) {
+ r = const_chain(1, &c->day);
+ if (r < 0)
+ goto fail;
+ r = const_chain(0, &c->hour);
+ if (r < 0)
+ goto fail;
+ r = const_chain(0, &c->minute);
+ if (r < 0)
+ goto fail;
+ r = const_chain(0, &c->second);
+ if (r < 0)
+ goto fail;
+
+ } else if (strcasecmp(p, "weekly") == 0) {
+
+ c->weekdays_bits = 1;
+
+ r = const_chain(0, &c->hour);
+ if (r < 0)
+ goto fail;
+ r = const_chain(0, &c->minute);
+ if (r < 0)
+ goto fail;
+ r = const_chain(0, &c->second);
+ if (r < 0)
+ goto fail;
+
+ } else {
+ r = parse_weekdays(&p, c);
+ if (r < 0)
+ goto fail;
+
+ r = parse_date(&p, c);
+ if (r < 0)
+ goto fail;
+
+ r = parse_time(&p, c);
+ if (r < 0)
+ goto fail;
+
+ if (*p != 0) {
+ r = -EINVAL;
+ goto fail;
+ }
+ }
+
+ r = calendar_spec_normalize(c);
+ if (r < 0)
+ goto fail;
+
+ if (!calendar_spec_valid(c)) {
+ r = -EINVAL;
+ goto fail;
+ }
+
+ *spec = c;
+ return 0;
+
+fail:
+ calendar_spec_free(c);
+ return r;
+}
+
+static int find_matching_component(const CalendarComponent *c, int *val) {
+ const CalendarComponent *n;
+ int d;
+ bool d_set = false;
+ int r;
+
+ assert(val);
+
+ if (!c)
+ return 0;
+
+ while (c) {
+ n = c->next;
+
+ if (c->value >= *val) {
+
+ if (!d_set || c->value < d) {
+ d = c->value;
+ d_set = true;
+ }
+
+ } else if (c->repeat > 0) {
+ int k;
+
+ k = c->value + c->repeat * ((*val - c->value + c->repeat -1) / c->repeat);
+
+ if (!d_set || k < d) {
+ d = k;
+ d_set = true;
+ }
+ }
+
+ c = n;
+ }
+
+ if (!d_set)
+ return -ENOENT;
+
+ r = *val != d;
+ *val = d;
+ return r;
+}
+
+static bool tm_out_of_bounds(const struct tm *tm) {
+ struct tm t;
+ assert(tm);
+
+ t = *tm;
+
+ if (mktime(&t) == (time_t) -1)
+ 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) {
+ struct tm t;
+ int k;
+
+ if (weekdays_bits < 0 || weekdays_bits >= 127)
+ return true;
+
+ t = *tm;
+ if (mktime(&t) == (time_t) -1)
+ 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) {
+ struct tm c;
+ int r;
+
+ assert(spec);
+ assert(tm);
+
+ c = *tm;
+
+ for (;;) {
+ /* Normalize the current date */
+ mktime(&c);
+ c.tm_isdst = -1;
+
+ c.tm_year += 1900;
+ r = find_matching_component(spec->year, &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 = 0;
+ }
+ if (r < 0 || tm_out_of_bounds(&c))
+ return r;
+
+ c.tm_mon += 1;
+ r = find_matching_component(spec->month, &c.tm_mon);
+ c.tm_mon -= 1;
+
+ if (r > 0) {
+ c.tm_mday = 1;
+ c.tm_hour = c.tm_min = c.tm_sec = 0;
+ }
+ if (r < 0 || tm_out_of_bounds(&c)) {
+ c.tm_year ++;
+ c.tm_mon = 0;
+ c.tm_mday = 1;
+ c.tm_hour = c.tm_min = c.tm_sec = 0;
+ continue;
+ }
+
+ r = find_matching_component(spec->day, &c.tm_mday);
+ if (r > 0)
+ c.tm_hour = c.tm_min = c.tm_sec = 0;
+ if (r < 0 || tm_out_of_bounds(&c)) {
+ c.tm_mon ++;
+ c.tm_mday = 1;
+ c.tm_hour = c.tm_min = c.tm_sec = 0;
+ continue;
+ }
+
+ if (!matches_weekday(spec->weekdays_bits, &c)) {
+ c.tm_mday++;
+ c.tm_hour = c.tm_min = c.tm_sec = 0;
+ continue;
+ }
+
+ r = find_matching_component(spec->hour, &c.tm_hour);
+ if (r > 0)
+ c.tm_min = c.tm_sec = 0;
+ if (r < 0 || tm_out_of_bounds(&c)) {
+ c.tm_mday ++;
+ c.tm_hour = c.tm_min = c.tm_sec = 0;
+ continue;
+ }
+
+ r = find_matching_component(spec->minute, &c.tm_min);
+ if (r > 0)
+ c.tm_sec = 0;
+ if (r < 0 || tm_out_of_bounds(&c)) {
+ c.tm_hour ++;
+ c.tm_min = c.tm_sec = 0;
+ continue;
+ }
+
+ r = find_matching_component(spec->second, &c.tm_sec);
+ if (r < 0 || tm_out_of_bounds(&c)) {
+ c.tm_min ++;
+ c.tm_sec = 0;
+ continue;
+ }
+
+
+ *tm = c;
+ return 0;
+ }
+}
+
+int calendar_spec_next_usec(const CalendarSpec *spec, usec_t usec, usec_t *next) {
+ struct tm tm;
+ time_t t;
+ int r;
+
+ assert(spec);
+ assert(next);
+
+ t = (time_t) (usec / USEC_PER_SEC) + 1;
+ assert_se(localtime_r(&t, &tm));
+
+ r = find_next(spec, &tm);
+ if (r < 0)
+ return r;
+
+ t = mktime(&tm);
+ if (t == (time_t) -1)
+ return -EINVAL;
+
+
+ *next = (usec_t) t * USEC_PER_SEC;
+ return 0;
+}