Re: Code for user-defined type

Hello

2014-05-27 20:30 GMT+02:00 Paul Jones <pbj(at)cmicdo(dot)com>:

> I have written a user-defined type that allows direct import and printing
> of
> DB2 timestamps.It does correctly import and export DB2 timestamps,
> butI'm wondering ifsomeone could tell me if I made anymistakes in
> the C code, particularly w.r.t. memory leaks or non-portableconstructs.
>
>
> I'm doing this on 9.3.4.
>
> Thanks,
> PJ
>
>
> ------------------ SQL ---------------------------
>
>
> CREATE TYPE db2tstz;
>
> CREATE FUNCTION db2tstzin(cstring) RETURNS db2tstz
> AS '/home/paul/src/pgproj/types/db2tstz.so', 'db2tstzin'
> LANGUAGE C STRICT;
>
> CREATE FUNCTION db2tstzout(db2tstz) RETURNS cstring
> AS '/home/paul/src/pgproj/types/db2tstz.so', 'db2tstzout'
> LANGUAGE C STRICT;
>
> CREATE TYPE db2tstz (
> INPUT = db2tstzin,
> OUTPUT = db2tstzout,
> LIKE = timestamptz
> );
>
> CREATE TABLE foo
> (
> aaa INT,
> bbb DB2TSTZ
> );
>

>
> INSERT INTO foo VALUES (1, '2013-10-03-17.22.18.823581'),
> (2, '2010-04-06-13.16.47.174372');
>
> ---------------- C Code ----------------
>
> #include "postgres.h"
> #include <string.h>
> #include "fmgr.h"
> #include "utils/formatting.h"
> #include "utils/datetime.h"
>
> #ifdef PG_MODULE_MAGIC
> PG_MODULE_MAGIC;
> #endif
>
> /* by value */
>
> PG_FUNCTION_INFO_V1(db2tstzin);
>
> Datum
> db2tstzin(PG_FUNCTION_ARGS)
> {
> char *date_txt = PG_GETARG_CSTRING(0);
> Timestamp tsp;
>
> tsp = DirectFunctionCall2(to_timestamp,
> cstring_to_text(date_txt),
> cstring_to_text("YYYY-MM-DD-HH24.MI.SS.US"));
>
> PG_RETURN_DATUM(tsp);
> }
>
> PG_FUNCTION_INFO_V1(db2tstzout);
>
>

There is one issue DirectFunctionCall takes a parameters converted to Datum
and returns Datum

You should to use a macros XGetDatum and DatumGetX

In this case

newDate = DatumGetTimestamp(DirectFunctionCall2(to_timestamp,
CStringGetDatum(date_txt),
CStringGetDatum(cstring_to_text(nls_date_format))));

PG_RETURN_TIMESTAMP(newDate);

There is inconsistency in types - Timestamp and Timestamptz -

> Datum
> db2tstzout(PG_FUNCTION_ARGS)
> {
> TimestampTz tsp = PG_GETARG_TIMESTAMPTZ(0);
> text *result;
>
> result = (text *)DirectFunctionCall2(timestamp_to_char,
> (int)&tsp,
> cstring_to_text("YYYY-MM-DD-HH24.MI.SS.US"));
>
> PG_RETURN_CSTRING(text_to_cstring(result));
> }
>
>
Regards

Pavel

>
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