diff options
Diffstat (limited to 'src/include/fmgr.h')
| -rw-r--r-- | src/include/fmgr.h | 60 |
1 files changed, 39 insertions, 21 deletions
diff --git a/src/include/fmgr.h b/src/include/fmgr.h index c68abfcf85e..b0aea5df09e 100644 --- a/src/include/fmgr.h +++ b/src/include/fmgr.h @@ -11,7 +11,7 @@ * Portions Copyright (c) 1996-2000, PostgreSQL, Inc * Portions Copyright (c) 1994, Regents of the University of California * - * $Id: fmgr.h,v 1.6 2000/06/14 05:24:50 tgl Exp $ + * $Id: fmgr.h,v 1.7 2000/07/06 05:48:17 tgl Exp $ * *------------------------------------------------------------------------- */ @@ -94,22 +94,30 @@ extern void fmgr_info(Oid functionId, FmgrInfo *finfo); /* Standard parameter list for fmgr-compatible functions */ #define PG_FUNCTION_ARGS FunctionCallInfo fcinfo -/* If function is not marked "proisstrict" in pg_proc, it must check for +/* + * If function is not marked "proisstrict" in pg_proc, it must check for * null arguments using this macro. Do not try to GETARG a null argument! */ #define PG_ARGISNULL(n) (fcinfo->argnull[n]) -#if 1 -/* VERY TEMPORARY until some TOAST support is committed ... */ -#define PG_DETOAST_DATUM(datum) \ - ((struct varlena *) DatumGetPointer(datum)) -#else -/* Eventually it will look more like this... */ -#define PG_DETOAST_DATUM(datum) \ - (VARATT_IS_EXTENDED(DatumGetPointer(datum)) ? \ - (struct varlena *) heap_tuple_untoast_attr((varattrib *) DatumGetPointer(datum)) : \ - (struct varlena *) DatumGetPointer(datum)) -#endif +/* + * Support for fetching detoasted copies of toastable datatypes (all of + * which are varlena types). pg_detoast_datum() gives you either the input + * datum (if not toasted) or a detoasted copy allocated with palloc(). + * pg_detoast_datum_copy() always gives you a palloc'd copy --- use it + * if you need a modifiable copy of the input. Caller is expected to have + * checked for null inputs first, if necessary. + * + * Note: it'd be nice if these could be macros, but I see no way to do that + * without evaluating the arguments multiple times, which is NOT acceptable. + */ +extern struct varlena * pg_detoast_datum(struct varlena * datum); +extern struct varlena * pg_detoast_datum_copy(struct varlena * datum); + +#define PG_DETOAST_DATUM(datum) \ + pg_detoast_datum((struct varlena *) DatumGetPointer(datum)) +#define PG_DETOAST_DATUM_COPY(datum) \ + pg_detoast_datum_copy((struct varlena *) DatumGetPointer(datum)) /* Macros for fetching arguments of standard types */ @@ -133,15 +141,25 @@ extern void fmgr_info(Oid functionId, FmgrInfo *finfo); /* use this if you want the input datum de-toasted: */ #define PG_GETARG_VARLENA_P(n) PG_DETOAST_DATUM(PG_GETARG_DATUM(n)) /* DatumGetFoo macros for varlena types will typically look like this: */ -#define DatumGetByteaP(X) ((bytea *) PG_DETOAST_DATUM(X)) -#define DatumGetTextP(X) ((text *) PG_DETOAST_DATUM(X)) -#define DatumGetBpCharP(X) ((BpChar *) PG_DETOAST_DATUM(X)) -#define DatumGetVarCharP(X) ((VarChar *) PG_DETOAST_DATUM(X)) +#define DatumGetByteaP(X) ((bytea *) PG_DETOAST_DATUM(X)) +#define DatumGetTextP(X) ((text *) PG_DETOAST_DATUM(X)) +#define DatumGetBpCharP(X) ((BpChar *) PG_DETOAST_DATUM(X)) +#define DatumGetVarCharP(X) ((VarChar *) PG_DETOAST_DATUM(X)) +/* And we also offer variants that return an OK-to-write copy */ +#define DatumGetByteaPCopy(X) ((bytea *) PG_DETOAST_DATUM_COPY(X)) +#define DatumGetTextPCopy(X) ((text *) PG_DETOAST_DATUM_COPY(X)) +#define DatumGetBpCharPCopy(X) ((BpChar *) PG_DETOAST_DATUM_COPY(X)) +#define DatumGetVarCharPCopy(X) ((VarChar *) PG_DETOAST_DATUM_COPY(X)) /* GETARG macros for varlena types will typically look like this: */ -#define PG_GETARG_BYTEA_P(n) DatumGetByteaP(PG_GETARG_DATUM(n)) -#define PG_GETARG_TEXT_P(n) DatumGetTextP(PG_GETARG_DATUM(n)) -#define PG_GETARG_BPCHAR_P(n) DatumGetBpCharP(PG_GETARG_DATUM(n)) -#define PG_GETARG_VARCHAR_P(n) DatumGetVarCharP(PG_GETARG_DATUM(n)) +#define PG_GETARG_BYTEA_P(n) DatumGetByteaP(PG_GETARG_DATUM(n)) +#define PG_GETARG_TEXT_P(n) DatumGetTextP(PG_GETARG_DATUM(n)) +#define PG_GETARG_BPCHAR_P(n) DatumGetBpCharP(PG_GETARG_DATUM(n)) +#define PG_GETARG_VARCHAR_P(n) DatumGetVarCharP(PG_GETARG_DATUM(n)) +/* And we also offer variants that return an OK-to-write copy */ +#define PG_GETARG_BYTEA_P_COPY(n) DatumGetByteaPCopy(PG_GETARG_DATUM(n)) +#define PG_GETARG_TEXT_P_COPY(n) DatumGetTextPCopy(PG_GETARG_DATUM(n)) +#define PG_GETARG_BPCHAR_P_COPY(n) DatumGetBpCharPCopy(PG_GETARG_DATUM(n)) +#define PG_GETARG_VARCHAR_P_COPY(n) DatumGetVarCharPCopy(PG_GETARG_DATUM(n)) /* To return a NULL do this: */ #define PG_RETURN_NULL() \ |