diff options
Diffstat (limited to 'src/backend/utils/adt/datetime.c')
| -rw-r--r-- | src/backend/utils/adt/datetime.c | 125 |
1 files changed, 118 insertions, 7 deletions
diff --git a/src/backend/utils/adt/datetime.c b/src/backend/utils/adt/datetime.c index ab0a3b4e89e..81f7e63650c 100644 --- a/src/backend/utils/adt/datetime.c +++ b/src/backend/utils/adt/datetime.c @@ -8,7 +8,7 @@ * * * IDENTIFICATION - * $PostgreSQL: pgsql/src/backend/utils/adt/datetime.c,v 1.170 2006/09/04 01:26:27 tgl Exp $ + * $PostgreSQL: pgsql/src/backend/utils/adt/datetime.c,v 1.171 2006/09/16 20:14:33 tgl Exp $ * *------------------------------------------------------------------------- */ @@ -3839,21 +3839,21 @@ InstallTimeZoneAbbrevs(tzEntry *abbrevs, int n) /* * This set-returning function reads all the available time zone abbreviations - * and returns a set of (name, utc_offset, is_dst). + * and returns a set of (abbrev, utc_offset, is_dst). */ Datum -pg_timezonenames(PG_FUNCTION_ARGS) +pg_timezone_abbrevs(PG_FUNCTION_ARGS) { FuncCallContext *funcctx; int *pindex; Datum result; - Interval *resInterval; HeapTuple tuple; Datum values[3]; bool nulls[3]; char buffer[TOKMAXLEN + 1]; unsigned char *p; struct pg_tm tm; + Interval *resInterval; /* stuff done only on the first call of the function */ if (SRF_IS_FIRSTCALL()) @@ -3876,11 +3876,11 @@ pg_timezonenames(PG_FUNCTION_ARGS) funcctx->user_fctx = (void *) pindex; /* - * build tupdesc for result tuples. This must match the - * definition of the pg_timezonenames view in system_views.sql + * build tupdesc for result tuples. This must match this function's + * pg_proc entry! */ tupdesc = CreateTemplateTupleDesc(3, false); - TupleDescInitEntry(tupdesc, (AttrNumber) 1, "name", + TupleDescInitEntry(tupdesc, (AttrNumber) 1, "abbrev", TEXTOID, -1, 0); TupleDescInitEntry(tupdesc, (AttrNumber) 2, "utc_offset", INTERVALOID, -1, 0); @@ -3928,3 +3928,114 @@ pg_timezonenames(PG_FUNCTION_ARGS) SRF_RETURN_NEXT(funcctx, result); } + +/* + * This set-returning function reads all the available full time zones + * and returns a set of (name, abbrev, utc_offset, is_dst). + */ +Datum +pg_timezone_names(PG_FUNCTION_ARGS) +{ + MemoryContext oldcontext; + FuncCallContext *funcctx; + pg_tzenum *tzenum; + pg_tz *tz; + Datum result; + HeapTuple tuple; + Datum values[4]; + bool nulls[4]; + int tzoff; + struct pg_tm tm; + fsec_t fsec; + char *tzn; + Interval *resInterval; + struct pg_tm itm; + + /* stuff done only on the first call of the function */ + if (SRF_IS_FIRSTCALL()) + { + TupleDesc tupdesc; + + /* create a function context for cross-call persistence */ + funcctx = SRF_FIRSTCALL_INIT(); + + /* + * switch to memory context appropriate for multiple function + * calls + */ + oldcontext = MemoryContextSwitchTo(funcctx->multi_call_memory_ctx); + + /* initialize timezone scanning code */ + tzenum = pg_tzenumerate_start(); + funcctx->user_fctx = (void *) tzenum; + + /* + * build tupdesc for result tuples. This must match this function's + * pg_proc entry! + */ + tupdesc = CreateTemplateTupleDesc(4, false); + TupleDescInitEntry(tupdesc, (AttrNumber) 1, "name", + TEXTOID, -1, 0); + TupleDescInitEntry(tupdesc, (AttrNumber) 2, "abbrev", + TEXTOID, -1, 0); + TupleDescInitEntry(tupdesc, (AttrNumber) 3, "utc_offset", + INTERVALOID, -1, 0); + TupleDescInitEntry(tupdesc, (AttrNumber) 4, "is_dst", + BOOLOID, -1, 0); + + funcctx->tuple_desc = BlessTupleDesc(tupdesc); + MemoryContextSwitchTo(oldcontext); + } + + /* stuff done on every call of the function */ + funcctx = SRF_PERCALL_SETUP(); + tzenum = (pg_tzenum *) funcctx->user_fctx; + + /* search for another zone to display */ + for (;;) + { + oldcontext = MemoryContextSwitchTo(funcctx->multi_call_memory_ctx); + tz = pg_tzenumerate_next(tzenum); + MemoryContextSwitchTo(oldcontext); + + if (!tz) + { + pg_tzenumerate_end(tzenum); + funcctx->user_fctx = NULL; + SRF_RETURN_DONE(funcctx); + } + + /* Convert now() to local time in this zone */ + if (timestamp2tm(GetCurrentTransactionStartTimestamp(), + &tzoff, &tm, &fsec, &tzn, tz) != 0) + continue; /* ignore if conversion fails */ + + /* Ignore zic's rather silly "Factory" time zone */ + if (tzn && strcmp(tzn, "Local time zone must be set--see zic manual page") == 0) + continue; + + /* Found a displayable zone */ + break; + } + + MemSet(nulls, 0, sizeof(nulls)); + + values[0] = DirectFunctionCall1(textin, + CStringGetDatum(pg_get_timezone_name(tz))); + + values[1] = DirectFunctionCall1(textin, + CStringGetDatum(tzn ? tzn : "")); + + MemSet(&itm, 0, sizeof(struct pg_tm)); + itm.tm_sec = -tzoff; + resInterval = (Interval *) palloc(sizeof(Interval)); + tm2interval(&itm, 0, resInterval); + values[2] = IntervalPGetDatum(resInterval); + + values[3] = BoolGetDatum(tm.tm_isdst > 0); + + tuple = heap_form_tuple(funcctx->tuple_desc, values, nulls); + result = HeapTupleGetDatum(tuple); + + SRF_RETURN_NEXT(funcctx, result); +} |