diff --git a/changelogs/unreleased/gh-6751-olson-timezones.md b/changelogs/unreleased/gh-6751-olson-timezones.md
new file mode 100644
index 0000000000000000000000000000000000000000..f9c577d4e9755d78598751daff416188e4fe052e
--- /dev/null
+++ b/changelogs/unreleased/gh-6751-olson-timezones.md
@@ -0,0 +1,4 @@
+## feature/datetime
+
+ * `isdst` field in datetime object is now properly calculated according to
+ IANA tzdata (aka Olson DB) rules for given date/time moment (gh-6751);
diff --git a/extra/exports b/extra/exports
index 9dc404f01087a8fc1621bf1e861f57486dbc42fa..c88f0304b4495a2988ae870c5b09342f8dfd61a4 100644
--- a/extra/exports
+++ b/extra/exports
@@ -432,6 +432,7 @@ title_set_status
title_update
tnt_datetime_datetime_sub
tnt_datetime_increment_by
+tnt_datetime_isdst
tnt_datetime_now
tnt_datetime_parse_full
tnt_datetime_parse_tz
diff --git a/src/lib/core/datetime.c b/src/lib/core/datetime.c
index 62fd5da0fa1b7e00d41bc4614eb62f7c9d92358a..a9d9bd84aab0b6eaf6a057f501731ba64b782dad 100644
--- a/src/lib/core/datetime.c
+++ b/src/lib/core/datetime.c
@@ -47,6 +47,48 @@ local_secs(const struct datetime *date)
return (int64_t)date->epoch + date->tzoffset * 60;
}
+/**
+ * Resolve tzindex encoded timezone from @sa date using Olson facilities.
+ * @param[in] date decode input datetime value.
+ * @param[out] gmtoff return resolved timezone offset (in seconds).
+ * @param[out] isdst return resolved daylight saving time status for the zone.
+ */
+static inline bool
+datetime_timezone_lookup(const struct datetime *date, long *gmtoff, int *isdst)
+{
+ if (date->tzindex == 0)
+ return false;
+
+ struct tnt_tm tm = {.tm_epoch = date->epoch};
+ if (!timezone_tzindex_lookup(date->tzindex, &tm))
+ return false;
+
+ *gmtoff = tm.tm_gmtoff;
+ *isdst = tm.tm_isdst;
+
+ return true;
+}
+
+bool
+datetime_isdst(const struct datetime *date)
+{
+ int isdst = 0;
+ long gmtoff = 0;
+
+ return datetime_timezone_lookup(date, &gmtoff, &isdst) && (isdst != 0);
+}
+
+long
+datetime_gmtoff(const struct datetime *date)
+{
+ int isdst = 0;
+ long gmtoff = date->tzoffset * 60;
+
+ datetime_timezone_lookup(date, &gmtoff, &isdst);
+
+ return gmtoff;
+}
+
void
datetime_to_tm(const struct datetime *date, struct tnt_tm *tm)
{
@@ -721,7 +763,7 @@ datetime_increment_by(struct datetime *self, int direction,
int64_t secs = local_secs(self);
int64_t dt = local_dt(secs);
int nsec = self->nsec;
- int offset = self->tzindex;
+ int offset = self->tzoffset;
bool is_ymd_updated = false;
int64_t years = ival->year;
@@ -809,6 +851,7 @@ datetime_increment_by(struct datetime *self, int direction,
self->epoch = utc_secs(secs, offset);
self->nsec = nsec;
+ self->tzoffset = datetime_gmtoff(self) / 60;
return 0;
}
diff --git a/src/lib/core/datetime.h b/src/lib/core/datetime.h
index ca5dbee1b44b92d56671814fdb1269e719ca94d2..91f8bce8aa5576a5ae56c4642b44621a7d672b95 100644
--- a/src/lib/core/datetime.h
+++ b/src/lib/core/datetime.h
@@ -164,6 +164,18 @@ datetime_to_tm(const struct datetime *date, struct tnt_tm *tm);
bool
tm_to_datetime(struct tnt_tm *tm, struct datetime *date);
+/**
+ * Return whether given @sa datetime moment is DST.
+ */
+bool
+datetime_isdst(const struct datetime *date);
+
+/**
+ * Return gmtoff of a given @sa datetime moment.
+ */
+long
+datetime_gmtoff(const struct datetime *date);
+
/**
* Parse datetime text in ISO-8601 given format, and construct output
* datetime value
diff --git a/src/lib/tzcode/gen-zone-abbrevs.pl b/src/lib/tzcode/gen-zone-abbrevs.pl
index 37dda6219ff704aed3e0597eceea48574d6e3367..61ae07b428d047e96bd6ad1723724f9c1e51ed4d 100755
--- a/src/lib/tzcode/gen-zone-abbrevs.pl
+++ b/src/lib/tzcode/gen-zone-abbrevs.pl
@@ -110,6 +110,9 @@ BEGIN {
TZ_MILITARY => 0x04,
TZ_AMBIGUOUS => 0x08,
TZ_NYI => 0x10,
+ TZ_OLSON => 0x20,
+ TZ_ALIAS => 0x40,
+ TZ_DST => 0x80,
);
require constant; constant->import(\%flags);
%FlagName = reverse %flags;
@@ -156,6 +159,10 @@ sub read_abbrevs_file($) {
$offset = $h * 60 + $m;
}
+ if (/(Daylight|Summer)/) {
+ $flags |= TZ_DST;
+ }
+
if ( exists $ZoneAbbrevs{$encoded} ) {
$flags |= TZ_AMBIGUOUS;
$offset = 0;
diff --git a/src/lib/tzcode/timezone.c b/src/lib/tzcode/timezone.c
index c4cd0a5a2dc8e90e580cce4f45076ad608a8e801..b53777723dc5d924733e9f4da00b949ab0bdb859 100644
--- a/src/lib/tzcode/timezone.c
+++ b/src/lib/tzcode/timezone.c
@@ -79,6 +79,12 @@ timezone_flags(const struct date_time_zone *zone)
return zone->flags;
}
+bool
+timezone_isdst(const struct date_time_zone *zone)
+{
+ return !!(zone->flags & TZ_DST);
+}
+
const char*
timezone_name(int64_t index)
{
@@ -124,10 +130,9 @@ timezone_raw_lookup(const char *str, size_t len,
if (found != NULL) {
/* lua assumes that single bit is set, not both */
- assert((found->flags & (TZ_NYI | TZ_AMBIGUOUS)) !=
- (TZ_NYI | TZ_AMBIGUOUS));
- if (found->flags & (TZ_NYI | TZ_AMBIGUOUS))
- return -found->flags;
+ assert((found->flags & TZ_ERROR_MASK) != TZ_ERROR_MASK);
+ if (found->flags & TZ_ERROR_MASK)
+ return -(found->flags & TZ_ERROR_MASK);
*zone = found;
return len;
}
@@ -147,7 +152,7 @@ timezone_tm_lookup(const char *str, size_t len,
if ((found->flags & TZ_OLSON) == 0) {
tm->tm_gmtoff = found->offset * 60;
tm->tm_tzindex = found->id;
- tm->tm_isdst = false;
+ tm->tm_isdst = !!(found->flags & TZ_DST);
return rc;
}
timezone_t tz = tzalloc(str); // FIXME - cache loaded
@@ -199,3 +204,25 @@ timezone_epoch_lookup(const char *str, size_t len, time_t base,
tzfree(tz);
return 0;
}
+
+bool
+timezone_tzindex_lookup(int16_t tzindex, struct tnt_tm *tm)
+{
+ assert(tm != NULL);
+ if (tzindex == 0)
+ return false;
+
+ timezone_t tz = tzalloc(timezone_name(tzindex));
+ if (tz == NULL)
+ return false;
+ time_t epoch = (int64_t)tm->tm_epoch;
+ struct tnt_tm *result = tnt_localtime_rz(tz, &epoch, tm);
+ if (result == NULL)
+ goto exit_failure;
+ tzfree(tz);
+ return true;
+exit_failure:
+ if (tz != NULL)
+ tzfree(tz);
+ return false;
+}
diff --git a/src/lib/tzcode/timezone.h b/src/lib/tzcode/timezone.h
index b8eaf8e3d9557d1429847b11eba1f536449e0327..ea9b3c65654d29ec62c6b398ee7126593b208918 100644
--- a/src/lib/tzcode/timezone.h
+++ b/src/lib/tzcode/timezone.h
@@ -21,6 +21,7 @@ enum {
TZ_NYI = 0x10,
TZ_OLSON = 0x20,
TZ_ALIAS = 0x40,
+ TZ_DST = 0x80,
TZ_ERROR_MASK = TZ_AMBIGUOUS | TZ_NYI,
};
@@ -67,6 +68,13 @@ timezone_tm_lookup(const char *str, size_t len,
const struct date_time_zone **zone,
struct tnt_tm *tm);
+/**
+ * Parse timezone string corresponding to @sa tzindex like
+ * @sa timezone_tm_lookup does.
+ */
+bool
+timezone_tzindex_lookup(int16_t tzindex, struct tnt_tm *tm);
+
/** Return offset in minutes for given zone */
int16_t
timezone_offset(const struct date_time_zone *zone);
@@ -76,6 +84,9 @@ timezone_index(const struct date_time_zone *zone);
/** Return attributes flags for given zone */
uint16_t
timezone_flags(const struct date_time_zone *zone);
+/** Return DST flag for given zone */
+bool
+timezone_isdst(const struct date_time_zone *zone);
/** Translate tzindex to zone name */
const char*
timezone_name(int64_t index);
diff --git a/src/lib/tzcode/timezones.h b/src/lib/tzcode/timezones.h
index b412b585b6c378cb92316c9cd35f4db08be9de15..12d76d8302dff0a554bc1da1aca1321f8b547239 100644
--- a/src/lib/tzcode/timezones.h
+++ b/src/lib/tzcode/timezones.h
@@ -37,13 +37,13 @@ ZONE_ABBREV( 104, 780, "ST", 0)
ZONE_ABBREV( 112, 0, "UT", TZ_UTC|TZ_RFC)
ZONE_ABBREV( 120, 0, "WT", 0)
ZONE_ABBREV( 128, 0, "ACT", TZ_AMBIGUOUS)
-ZONE_ABBREV( 129, 0, "ADT", TZ_AMBIGUOUS)
+ZONE_ABBREV( 129, 0, "ADT", TZ_AMBIGUOUS|TZ_DST)
ZONE_ABBREV( 130, 0, "AET", TZ_AMBIGUOUS)
ZONE_ABBREV( 131, 270, "AFT", 0)
ZONE_ABBREV( 132, 0, "AMT", TZ_AMBIGUOUS)
ZONE_ABBREV( 133, -720, "AoE", 0)
ZONE_ABBREV( 134, -180, "ART", 0)
-ZONE_ABBREV( 135, 0, "AST", TZ_AMBIGUOUS)
+ZONE_ABBREV( 135, 0, "AST", TZ_AMBIGUOUS|TZ_DST)
ZONE_ABBREV( 136, 240, "AZT", 0)
ZONE_ABBREV( 144, 0, "BDT", TZ_AMBIGUOUS)
ZONE_ABBREV( 145, 480, "BNT", 0)
@@ -53,7 +53,7 @@ ZONE_ABBREV( 148, 0, "BST", TZ_AMBIGUOUS)
ZONE_ABBREV( 149, 360, "BTT", 0)
ZONE_ABBREV( 152, 120, "CAT", 0)
ZONE_ABBREV( 153, 390, "CCT", 0)
-ZONE_ABBREV( 154, -300, "CDT", TZ_RFC|TZ_AMBIGUOUS)
+ZONE_ABBREV( 154, -300, "CDT", TZ_RFC|TZ_AMBIGUOUS|TZ_DST)
ZONE_ABBREV( 155, 60, "CET", 0)
ZONE_ABBREV( 156, -300, "CIT", 0)
ZONE_ABBREV( 157, -600, "CKT", 0)
@@ -64,7 +64,7 @@ ZONE_ABBREV( 161, -60, "CVT", 0)
ZONE_ABBREV( 162, 420, "CXT", 0)
ZONE_ABBREV( 168, 180, "EAT", 0)
ZONE_ABBREV( 169, 0, "ECT", TZ_AMBIGUOUS)
-ZONE_ABBREV( 170, -240, "EDT", TZ_RFC|TZ_AMBIGUOUS)
+ZONE_ABBREV( 170, -240, "EDT", TZ_RFC|TZ_AMBIGUOUS|TZ_DST)
ZONE_ABBREV( 171, 120, "EET", 0)
ZONE_ABBREV( 172, -60, "EGT", 0)
ZONE_ABBREV( 173, -300, "EST", TZ_RFC|TZ_AMBIGUOUS)
@@ -83,7 +83,7 @@ ZONE_ABBREV( 194, -240, "HAE", 0)
ZONE_ABBREV( 195, -420, "HAP", 0)
ZONE_ABBREV( 196, -360, "HAR", 0)
ZONE_ABBREV( 197, -90, "HAT", 0)
-ZONE_ABBREV( 198, -540, "HDT", 0)
+ZONE_ABBREV( 198, -540, "HDT", TZ_DST)
ZONE_ABBREV( 199, 480, "HKT", 0)
ZONE_ABBREV( 200, -210, "HLV", 0)
ZONE_ABBREV( 201, -240, "HNA", 0)
@@ -94,7 +94,7 @@ ZONE_ABBREV( 205, -420, "HNR", 0)
ZONE_ABBREV( 206, -150, "HNT", 0)
ZONE_ABBREV( 207, -600, "HST", 0)
ZONE_ABBREV( 208, 420, "ICT", 0)
-ZONE_ABBREV( 209, 0, "IDT", TZ_AMBIGUOUS)
+ZONE_ABBREV( 209, 0, "IDT", TZ_AMBIGUOUS|TZ_DST)
ZONE_ABBREV( 210, 360, "IOT", 0)
ZONE_ABBREV( 211, 0, "IST", TZ_AMBIGUOUS)
ZONE_ABBREV( 216, 540, "JST", 0)
@@ -102,25 +102,25 @@ ZONE_ABBREV( 224, 360, "KGT", 0)
ZONE_ABBREV( 225, 300, "KIT", 0)
ZONE_ABBREV( 226, 540, "KST", 0)
ZONE_ABBREV( 232, 180, "MCK", 0)
-ZONE_ABBREV( 233, -360, "MDT", TZ_RFC)
+ZONE_ABBREV( 233, -360, "MDT", TZ_RFC|TZ_DST)
ZONE_ABBREV( 234, 60, "MEZ", 0)
ZONE_ABBREV( 235, 720, "MHT", 0)
ZONE_ABBREV( 236, 390, "MMT", 0)
-ZONE_ABBREV( 237, 240, "MSD", 0)
+ZONE_ABBREV( 237, 240, "MSD", TZ_DST)
ZONE_ABBREV( 238, 180, "MSK", 0)
ZONE_ABBREV( 239, -420, "MST", TZ_RFC|TZ_AMBIGUOUS)
ZONE_ABBREV( 240, 240, "MUT", 0)
ZONE_ABBREV( 241, 300, "MVT", 0)
ZONE_ABBREV( 242, 480, "MYT", 0)
ZONE_ABBREV( 248, 660, "NCT", 0)
-ZONE_ABBREV( 249, -90, "NDT", 0)
+ZONE_ABBREV( 249, -90, "NDT", TZ_DST)
ZONE_ABBREV( 250, 660, "NFT", 0)
ZONE_ABBREV( 251, 345, "NPT", 0)
ZONE_ABBREV( 252, 720, "NRT", 0)
ZONE_ABBREV( 253, -150, "NST", 0)
ZONE_ABBREV( 254, -660, "NUT", 0)
ZONE_ABBREV( 256, 120, "OEZ", 0)
-ZONE_ABBREV( 264, -420, "PDT", TZ_RFC)
+ZONE_ABBREV( 264, -420, "PDT", TZ_RFC|TZ_DST)
ZONE_ABBREV( 265, -300, "PET", 0)
ZONE_ABBREV( 266, 600, "PGT", 0)
ZONE_ABBREV( 267, 480, "PHT", 0)
@@ -148,7 +148,7 @@ ZONE_ABBREV( 298, 300, "UZT", 0)
ZONE_ABBREV( 304, -210, "VET", 0)
ZONE_ABBREV( 305, 660, "VUT", 0)
ZONE_ABBREV( 312, 0, "WAT", TZ_AMBIGUOUS)
-ZONE_ABBREV( 313, 540, "WDT", 0)
+ZONE_ABBREV( 313, 540, "WDT", TZ_DST)
ZONE_ABBREV( 314, 0, "WET", 0)
ZONE_ABBREV( 315, 0, "WEZ", 0)
ZONE_ABBREV( 316, 720, "WFT", 0)
@@ -156,78 +156,78 @@ ZONE_ABBREV( 317, -180, "WGT", 0)
ZONE_ABBREV( 318, 420, "WIB", 0)
ZONE_ABBREV( 319, 540, "WIT", 0)
ZONE_ABBREV( 320, 0, "WST", TZ_AMBIGUOUS)
-ZONE_ABBREV( 328, 630, "ACDT", 0)
+ZONE_ABBREV( 328, 630, "ACDT", TZ_DST)
ZONE_ABBREV( 329, 570, "ACST", 0)
-ZONE_ABBREV( 330, 0, "ADST", TZ_AMBIGUOUS)
-ZONE_ABBREV( 331, 660, "AEDT", 0)
+ZONE_ABBREV( 330, 0, "ADST", TZ_AMBIGUOUS|TZ_DST)
+ZONE_ABBREV( 331, 660, "AEDT", TZ_DST)
ZONE_ABBREV( 332, 600, "AEST", 0)
-ZONE_ABBREV( 333, -480, "AKDT", 0)
+ZONE_ABBREV( 333, -480, "AKDT", TZ_DST)
ZONE_ABBREV( 334, -540, "AKST", 0)
ZONE_ABBREV( 335, 360, "ALMT", 0)
-ZONE_ABBREV( 336, 300, "AMDT", 0)
-ZONE_ABBREV( 337, 0, "AMST", TZ_AMBIGUOUS)
+ZONE_ABBREV( 336, 300, "AMDT", TZ_DST)
+ZONE_ABBREV( 337, 0, "AMST", TZ_AMBIGUOUS|TZ_DST)
ZONE_ABBREV( 338, 720, "ANAT", 0)
ZONE_ABBREV( 339, 300, "AQTT", 0)
-ZONE_ABBREV( 340, 540, "AWDT", 0)
+ZONE_ABBREV( 340, 540, "AWDT", TZ_DST)
ZONE_ABBREV( 341, 480, "AWST", 0)
ZONE_ABBREV( 342, -60, "AZOT", 0)
-ZONE_ABBREV( 343, 300, "AZST", 0)
-ZONE_ABBREV( 344, 60, "BDST", 0)
-ZONE_ABBREV( 345, -120, "BRST", 0)
+ZONE_ABBREV( 343, 300, "AZST", TZ_DST)
+ZONE_ABBREV( 344, 60, "BDST", TZ_DST)
+ZONE_ABBREV( 345, -120, "BRST", TZ_DST)
ZONE_ABBREV( 352, 480, "CAST", 0)
-ZONE_ABBREV( 353, 0, "CDST", TZ_AMBIGUOUS)
-ZONE_ABBREV( 354, 120, "CEDT", 0)
-ZONE_ABBREV( 355, 120, "CEST", 0)
+ZONE_ABBREV( 353, 0, "CDST", TZ_AMBIGUOUS|TZ_DST)
+ZONE_ABBREV( 354, 120, "CEDT", TZ_DST)
+ZONE_ABBREV( 355, 120, "CEST", TZ_DST)
ZONE_ABBREV( 356, 480, "CHOT", 0)
ZONE_ABBREV( 357, 600, "ChST", 0)
ZONE_ABBREV( 358, 600, "CHUT", 0)
ZONE_ABBREV( 359, -300, "CIST", 0)
-ZONE_ABBREV( 360, -180, "CLDT", 0)
+ZONE_ABBREV( 360, -180, "CLDT", TZ_DST)
ZONE_ABBREV( 361, 0, "CLST", TZ_AMBIGUOUS)
ZONE_ABBREV( 368, 420, "DAVT", 0)
ZONE_ABBREV( 369, 600, "DDUT", 0)
-ZONE_ABBREV( 376, -300, "EADT", 0)
+ZONE_ABBREV( 376, -300, "EADT", TZ_DST)
ZONE_ABBREV( 377, -300, "EAST", 0)
-ZONE_ABBREV( 378, 120, "ECST", 0)
-ZONE_ABBREV( 379, 0, "EDST", TZ_AMBIGUOUS)
-ZONE_ABBREV( 380, 180, "EEDT", 0)
-ZONE_ABBREV( 381, 180, "EEST", 0)
-ZONE_ABBREV( 382, 0, "EGST", 0)
-ZONE_ABBREV( 384, 780, "FJDT", 0)
-ZONE_ABBREV( 385, 780, "FJST", 0)
-ZONE_ABBREV( 386, -180, "FKDT", 0)
-ZONE_ABBREV( 387, 0, "FKST", TZ_AMBIGUOUS)
+ZONE_ABBREV( 378, 120, "ECST", TZ_DST)
+ZONE_ABBREV( 379, 0, "EDST", TZ_AMBIGUOUS|TZ_DST)
+ZONE_ABBREV( 380, 180, "EEDT", TZ_DST)
+ZONE_ABBREV( 381, 180, "EEST", TZ_DST)
+ZONE_ABBREV( 382, 0, "EGST", TZ_DST)
+ZONE_ABBREV( 384, 780, "FJDT", TZ_DST)
+ZONE_ABBREV( 385, 780, "FJST", TZ_DST)
+ZONE_ABBREV( 386, -180, "FKDT", TZ_DST)
+ZONE_ABBREV( 387, 0, "FKST", TZ_AMBIGUOUS|TZ_DST)
ZONE_ABBREV( 392, -360, "GALT", 0)
ZONE_ABBREV( 393, -540, "GAMT", 0)
ZONE_ABBREV( 394, 720, "GILT", 0)
-ZONE_ABBREV( 400, -540, "HADT", 0)
+ZONE_ABBREV( 400, -540, "HADT", TZ_DST)
ZONE_ABBREV( 401, -600, "HAST", 0)
ZONE_ABBREV( 402, 420, "HOVT", 0)
-ZONE_ABBREV( 408, 270, "IRDT", 0)
+ZONE_ABBREV( 408, 270, "IRDT", TZ_DST)
ZONE_ABBREV( 409, 480, "IRKT", 0)
-ZONE_ABBREV( 410, 0, "IRST", TZ_AMBIGUOUS)
+ZONE_ABBREV( 410, 0, "IRST", TZ_AMBIGUOUS|TZ_DST)
ZONE_ABBREV( 416, 660, "KOST", 0)
ZONE_ABBREV( 417, 420, "KRAT", 0)
ZONE_ABBREV( 418, 240, "KUYT", 0)
-ZONE_ABBREV( 424, 660, "LHDT", 0)
+ZONE_ABBREV( 424, 660, "LHDT", TZ_DST)
ZONE_ABBREV( 425, 630, "LHST", 0)
ZONE_ABBREV( 426, 840, "LINT", 0)
ZONE_ABBREV( 432, 600, "MAGT", 0)
ZONE_ABBREV( 433, -510, "MART", 0)
ZONE_ABBREV( 434, 300, "MAWT", 0)
-ZONE_ABBREV( 435, -360, "MDST", 0)
+ZONE_ABBREV( 435, -360, "MDST", TZ_DST)
ZONE_ABBREV( 436, 120, "MESZ", 0)
-ZONE_ABBREV( 440, 720, "NFDT", 0)
+ZONE_ABBREV( 440, 720, "NFDT", TZ_DST)
ZONE_ABBREV( 441, 360, "NOVT", 0)
-ZONE_ABBREV( 442, 780, "NZDT", 0)
+ZONE_ABBREV( 442, 780, "NZDT", TZ_DST)
ZONE_ABBREV( 443, 720, "NZST", 0)
ZONE_ABBREV( 448, 180, "OESZ", 0)
ZONE_ABBREV( 449, 360, "OMST", 0)
ZONE_ABBREV( 450, 300, "ORAT", 0)
-ZONE_ABBREV( 456, -420, "PDST", 0)
+ZONE_ABBREV( 456, -420, "PDST", TZ_DST)
ZONE_ABBREV( 457, 720, "PETT", 0)
ZONE_ABBREV( 458, 780, "PHOT", 0)
-ZONE_ABBREV( 459, -120, "PMDT", 0)
+ZONE_ABBREV( 459, -120, "PMDT", TZ_DST)
ZONE_ABBREV( 460, -180, "PMST", 0)
ZONE_ABBREV( 461, 660, "PONT", 0)
ZONE_ABBREV( 462, 0, "PYST", TZ_AMBIGUOUS)
@@ -239,56 +239,56 @@ ZONE_ABBREV( 482, 120, "SAST", 0)
ZONE_ABBREV( 483, 660, "SRET", 0)
ZONE_ABBREV( 484, 180, "SYOT", 0)
ZONE_ABBREV( 488, -600, "TAHT", 0)
-ZONE_ABBREV( 489, 840, "TOST", 0)
+ZONE_ABBREV( 489, 840, "TOST", TZ_DST)
ZONE_ABBREV( 496, 480, "ULAT", 0)
-ZONE_ABBREV( 497, -120, "UYST", 0)
+ZONE_ABBREV( 497, -120, "UYST", TZ_DST)
ZONE_ABBREV( 504, 600, "VLAT", 0)
ZONE_ABBREV( 505, 360, "VOST", 0)
ZONE_ABBREV( 512, 720, "WAKT", 0)
-ZONE_ABBREV( 513, 120, "WAST", 0)
-ZONE_ABBREV( 514, 60, "WEDT", 0)
-ZONE_ABBREV( 515, 60, "WEST", 0)
+ZONE_ABBREV( 513, 120, "WAST", TZ_DST)
+ZONE_ABBREV( 514, 60, "WEDT", TZ_DST)
+ZONE_ABBREV( 515, 60, "WEST", TZ_DST)
ZONE_ABBREV( 516, 60, "WESZ", 0)
-ZONE_ABBREV( 517, -120, "WGST", 0)
+ZONE_ABBREV( 517, -120, "WGST", TZ_DST)
ZONE_ABBREV( 518, 480, "WITA", 0)
ZONE_ABBREV( 520, 540, "YAKT", 0)
ZONE_ABBREV( 521, 600, "YAPT", 0)
ZONE_ABBREV( 522, 300, "YEKT", 0)
ZONE_ABBREV( 528, 525, "ACWST", 0)
-ZONE_ABBREV( 529, 720, "ANAST", 0)
-ZONE_ABBREV( 530, 0, "AZODT", 0)
-ZONE_ABBREV( 531, 0, "AZOST", TZ_AMBIGUOUS)
-ZONE_ABBREV( 536, 825, "CHADT", 0)
+ZONE_ABBREV( 529, 720, "ANAST", TZ_DST)
+ZONE_ABBREV( 530, 0, "AZODT", TZ_DST)
+ZONE_ABBREV( 531, 0, "AZOST", TZ_AMBIGUOUS|TZ_DST)
+ZONE_ABBREV( 536, 825, "CHADT", TZ_DST)
ZONE_ABBREV( 537, 765, "CHAST", 0)
-ZONE_ABBREV( 538, 540, "CHODT", 0)
-ZONE_ABBREV( 539, 540, "CHOST", 0)
-ZONE_ABBREV( 540, -240, "CIDST", 0)
-ZONE_ABBREV( 544, -300, "EASST", 0)
+ZONE_ABBREV( 538, 540, "CHODT", TZ_DST)
+ZONE_ABBREV( 539, 540, "CHOST", TZ_DST)
+ZONE_ABBREV( 540, -240, "CIDST", TZ_DST)
+ZONE_ABBREV( 544, -300, "EASST", TZ_DST)
ZONE_ABBREV( 545, 660, "EFATE", 0)
-ZONE_ABBREV( 552, 480, "HOVDT", 0)
-ZONE_ABBREV( 553, 480, "HOVST", 0)
-ZONE_ABBREV( 560, 540, "IRKST", 0)
-ZONE_ABBREV( 568, 480, "KRAST", 0)
-ZONE_ABBREV( 576, 720, "MAGST", 0)
-ZONE_ABBREV( 584, -300, "NACDT", 0)
+ZONE_ABBREV( 552, 480, "HOVDT", TZ_DST)
+ZONE_ABBREV( 553, 480, "HOVST", TZ_DST)
+ZONE_ABBREV( 560, 540, "IRKST", TZ_DST)
+ZONE_ABBREV( 568, 480, "KRAST", TZ_DST)
+ZONE_ABBREV( 576, 720, "MAGST", TZ_DST)
+ZONE_ABBREV( 584, -300, "NACDT", TZ_DST)
ZONE_ABBREV( 585, -360, "NACST", 0)
-ZONE_ABBREV( 586, -240, "NAEDT", 0)
+ZONE_ABBREV( 586, -240, "NAEDT", TZ_DST)
ZONE_ABBREV( 587, -300, "NAEST", 0)
-ZONE_ABBREV( 588, -360, "NAMDT", 0)
+ZONE_ABBREV( 588, -360, "NAMDT", TZ_DST)
ZONE_ABBREV( 589, -420, "NAMST", 0)
-ZONE_ABBREV( 590, -420, "NAPDT", 0)
+ZONE_ABBREV( 590, -420, "NAPDT", TZ_DST)
ZONE_ABBREV( 591, -480, "NAPST", 0)
-ZONE_ABBREV( 592, 420, "NOVST", 0)
-ZONE_ABBREV( 600, 420, "OMSST", 0)
-ZONE_ABBREV( 608, 720, "PETST", 0)
-ZONE_ABBREV( 616, 240, "SAMST", 0)
-ZONE_ABBREV( 624, 540, "ULAST", 0)
-ZONE_ABBREV( 632, 660, "VLAST", 0)
-ZONE_ABBREV( 640, -180, "WARST", 0)
-ZONE_ABBREV( 648, 600, "YAKST", 0)
-ZONE_ABBREV( 649, 360, "YEKST", 0)
-ZONE_ABBREV( 656, 540, "CHODST", 0)
-ZONE_ABBREV( 664, 480, "HOVDST", 0)
+ZONE_ABBREV( 592, 420, "NOVST", TZ_DST)
+ZONE_ABBREV( 600, 420, "OMSST", TZ_DST)
+ZONE_ABBREV( 608, 720, "PETST", TZ_DST)
+ZONE_ABBREV( 616, 240, "SAMST", TZ_DST)
+ZONE_ABBREV( 624, 540, "ULAST", TZ_DST)
+ZONE_ABBREV( 632, 660, "VLAST", TZ_DST)
+ZONE_ABBREV( 640, -180, "WARST", TZ_DST)
+ZONE_ABBREV( 648, 600, "YAKST", TZ_DST)
+ZONE_ABBREV( 649, 360, "YEKST", TZ_DST)
+ZONE_ABBREV( 656, 540, "CHODST", TZ_DST)
+ZONE_ABBREV( 664, 480, "HOVDST", TZ_DST)
ZONE_UNIQUE( 672, "Africa/Abidjan")
ZONE_UNIQUE( 673, "Africa/Algiers")
ZONE_UNIQUE( 674, "Africa/Bissau")
diff --git a/src/lua/datetime.lua b/src/lua/datetime.lua
index f5c53932de39c5107b90442526490c96be59f89b..7a44fb02d2da2a7bd10d427d7dc6360c5ad4bc6e 100644
--- a/src/lua/datetime.lua
+++ b/src/lua/datetime.lua
@@ -77,6 +77,7 @@ size_t tnt_datetime_strptime(struct datetime *date, const char *buf,
void tnt_datetime_now(struct datetime *now);
bool tnt_datetime_totable(const struct datetime *date,
struct interval *out);
+bool tnt_datetime_isdst(const struct datetime *date);
/* Tarantool interval support functions */
size_t tnt_interval_to_string(const struct interval *, char *, ssize_t);
@@ -446,6 +447,11 @@ local function epoch_from_dt(dt)
return (dt - DAYS_EPOCH_OFFSET) * SECS_PER_DAY
end
+-- Use Olson facilities to determine whether local time in obj is DST
+local function datetime_isdst(obj)
+ return builtin.tnt_datetime_isdst(obj)
+end
+
--[[
Parse timezone name similar way as datetime_parse_full parse
full literal.
@@ -953,7 +959,7 @@ local function datetime_totable(self)
hour = tmp_ival.hour,
min = tmp_ival.min,
sec = tmp_ival.sec,
- isdst = false,
+ isdst = datetime_isdst(self),
nsec = self.nsec,
tzoffset = self.tzoffset,
}
@@ -1163,7 +1169,7 @@ local datetime_index_fields = {
sec = function(self) return self.epoch % 60 end,
usec = function(self) return self.nsec / 1e3 end,
msec = function(self) return self.nsec / 1e6 end,
- isdst = function(_) return false end,
+ isdst = function(self) return datetime_isdst(self) end,
tz = function(self) return self:format('%Z') end,
}
diff --git a/src/lua/tnt_datetime.c b/src/lua/tnt_datetime.c
index f243d8e3c5ee62764523e39e4f64741c78017085..e948057c8a6ab83e0c85ae247bb5ab58ca1e4fa2 100644
--- a/src/lua/tnt_datetime.c
+++ b/src/lua/tnt_datetime.c
@@ -96,3 +96,9 @@ tnt_interval_unpack(const char **data, struct interval *itv)
{
return interval_unpack(data, itv);
}
+
+bool
+tnt_datetime_isdst(const struct datetime *date)
+{
+ return datetime_isdst(date);
+}
diff --git a/test/app-tap/datetime.test.lua b/test/app-tap/datetime.test.lua
index 08988cf84c126adafc84f8683bf0e3bf7ef7540b..dca81104cd37feece8d7731e815b1ed985fecef3 100755
--- a/test/app-tap/datetime.test.lua
+++ b/test/app-tap/datetime.test.lua
@@ -11,7 +11,7 @@ local ffi = require('ffi')
--]]
if jit.arch == 'arm64' then jit.off() end
-test:plan(37)
+test:plan(38)
-- minimum supported date - -5879610-06-22
local MIN_DATE_YEAR = -5879610
@@ -676,6 +676,59 @@ test:test("Parsing of timezone names (errors)", function(test)
end
end)
+test:test("Daylight saving checks", function (test)
+ --[[
+ Check various dates in `Europe/Moscow` timezone for their
+ proper daylight saving settings.
+
+ Tzdata defines these rules for `Europe/Moscow` time-zone:
+```
+Zone Europe/Moscow 2:30:17 - LMT 1880
+ 2:30:17 - MMT 1916 Jul 3 # Moscow Mean Time
+ 2:31:19 Russia %s 1919 Jul 1 0:00u
+ 3:00 Russia %s 1921 10
+ 3:00 Russia Europe/Moscow/Europe/Moscow 1922 10
+ 2:00 - EET 1930 Jun 21
+ 3:00 Russia Europe/Moscow/Europe/Moscow 1991 03 31 2:00s
+ 2:00 Russia EE%sT 1992 Jan 19 2:00s
+ 3:00 Russia Europe/Moscow/Europe/Moscow 2011 03 27 2:00s
+ 4:00 - Europe/Moscow 2014 10 26 2:00s
+ 3:00 - Europe/Moscow
+```
+ Either you could see the same table dumped in more or less
+ human-readable form using `zdump` utility:
+
+ `zdump -c 2004,2022 -v Europe/Moscow`
+ ]]
+ test:plan(30)
+ local moments = {
+ -- string, isdst?, tzoffset (mins)
+ {'2004-10-31T02:00:00 Europe/Moscow', false, 3 * 60},
+ {'2005-03-27T03:00:00 Europe/Moscow', true, 4 * 60},
+ {'2005-10-30T02:00:00 Europe/Moscow', false, 3 * 60},
+ {'2006-03-26T03:00:00 Europe/Moscow', true, 4 * 60},
+ {'2006-10-29T02:00:00 Europe/Moscow', false, 3 * 60},
+ {'2007-03-25T03:00:00 Europe/Moscow', true, 4 * 60},
+ {'2007-10-28T02:00:00 Europe/Moscow', false, 3 * 60},
+ {'2008-03-30T03:00:00 Europe/Moscow', true, 4 * 60},
+ {'2008-10-26T02:00:00 Europe/Moscow', false, 3 * 60},
+ {'2009-03-29T03:00:00 Europe/Moscow', true, 4 * 60},
+ {'2009-10-25T02:00:00 Europe/Moscow', false, 3 * 60},
+ {'2010-03-28T03:00:00 Europe/Moscow', true, 4 * 60},
+ {'2010-10-31T02:00:00 Europe/Moscow', false, 3 * 60},
+ {'2011-03-27T03:00:00 Europe/Moscow', false, 4 * 60},
+ {'2014-10-26T01:00:00 Europe/Moscow', false, 3 * 60},
+ }
+ for _, row in pairs(moments) do
+ local str, isdst, tzoffset = unpack(row)
+ local dt = date.parse(str)
+ test:is(dt.isdst, isdst,
+ ('%s: isdst = %s'):format(tostring(dt), dt.isdst))
+ test:is(dt.tzoffset, tzoffset,
+ ('%s: tzoffset = %s'):format(tostring(dt), dt.tzoffset))
+ end
+end)
+
test:test("Datetime string formatting", function(test)
test:plan(10)
local t = date.new()