@ -2,14 +2,14 @@
*
* heaptuple . c
* This file contains heap tuple accessor and mutator routines , as well
* as a few various tuple utilities .
* as various tuple utilities .
*
* Portions Copyright ( c ) 1996 - 2000 , PostgreSQL , Inc
* Portions Copyright ( c ) 1994 , Regents of the University of California
*
*
* IDENTIFICATION
* $ Header : / cvsroot / pgsql / src / backend / access / common / heaptuple . c , v 1.67 2000 / 11 / 30 18 : 38 : 45 tgl Exp $
* $ Header : / cvsroot / pgsql / src / backend / access / common / heaptuple . c , v 1.68 2000 / 12 / 27 23 : 59 : 10 tgl Exp $
*
* NOTES
* The old interface functions have been converted to macros
@ -23,16 +23,6 @@
# include "access/heapam.h"
# include "catalog/pg_type.h"
/* Used by heap_getattr() macro, for speed */
long heap_sysoffset [ ] = {
/* Only the first one is pass-by-ref, and is handled specially in the macro */
offsetof ( HeapTupleHeaderData , t_ctid ) ,
offsetof ( HeapTupleHeaderData , t_oid ) ,
offsetof ( HeapTupleHeaderData , t_xmin ) ,
offsetof ( HeapTupleHeaderData , t_cmin ) ,
offsetof ( HeapTupleHeaderData , t_xmax ) ,
offsetof ( HeapTupleHeaderData , t_cmax )
} ;
/* ----------------------------------------------------------------
* misc support routines
@ -48,12 +38,12 @@ ComputeDataSize(TupleDesc tupleDesc,
Datum * value ,
char * nulls )
{
uint32 data_length ;
uint32 data_length = 0 ;
int i ;
int numberOfAttributes = tupleDesc - > natts ;
Form_pg_attribute * att = tupleDesc - > attrs ;
for ( data_length = 0 , i = 0 ; i < numberOfAttributes ; i + + )
for ( i = 0 ; i < numberOfAttributes ; i + + )
{
if ( nulls [ i ] ! = ' ' )
continue ;
@ -114,38 +104,33 @@ DataFill(char *data,
* bitP | = bitmask ;
}
/* XXX we are aligning the pointer itself, not the offset */
data = ( char * ) att_align ( ( long ) data , att [ i ] - > attlen , att [ i ] - > attalign ) ;
switch ( att [ i ] - > attlen )
if ( att [ i ] - > attbyval )
{
case - 1 :
* infomask | = HEAP_HASVARLENA ;
if ( VARATT_IS_EXTERNAL ( value [ i ] ) )
* infomask | = HEAP_HASEXTERNAL ;
if ( VARATT_IS_COMPRESSED ( value [ i ] ) )
* infomask | = HEAP_HASCOMPRESSED ;
data_length = VARATT_SIZE ( DatumGetPointer ( value [ i ] ) ) ;
memmove ( data , DatumGetPointer ( value [ i ] ) , data_length ) ;
break ;
case sizeof ( char ) :
* data = att [ i ] - > attbyval ?
DatumGetChar ( value [ i ] ) : * ( ( char * ) value [ i ] ) ;
break ;
case sizeof ( int16 ) :
* ( short * ) data = ( att [ i ] - > attbyval ?
DatumGetInt16 ( value [ i ] ) :
* ( ( short * ) value [ i ] ) ) ;
break ;
case sizeof ( int32 ) :
* ( int32 * ) data = ( att [ i ] - > attbyval ?
DatumGetInt32 ( value [ i ] ) :
* ( ( int32 * ) value [ i ] ) ) ;
break ;
default :
Assert ( att [ i ] - > attlen > = 0 ) ;
memmove ( data , DatumGetPointer ( value [ i ] ) ,
( size_t ) ( att [ i ] - > attlen ) ) ;
break ;
/* pass-by-value */
store_att_byval ( data , value [ i ] , att [ i ] - > attlen ) ;
}
else if ( att [ i ] - > attlen = = - 1 )
{
/* varlena */
* infomask | = HEAP_HASVARLENA ;
if ( VARATT_IS_EXTERNAL ( value [ i ] ) )
* infomask | = HEAP_HASEXTERNAL ;
if ( VARATT_IS_COMPRESSED ( value [ i ] ) )
* infomask | = HEAP_HASCOMPRESSED ;
data_length = VARATT_SIZE ( DatumGetPointer ( value [ i ] ) ) ;
memcpy ( data , DatumGetPointer ( value [ i ] ) , data_length ) ;
}
else
{
/* fixed-length pass-by-reference */
Assert ( att [ i ] - > attlen > = 0 ) ;
memcpy ( data , DatumGetPointer ( value [ i ] ) ,
( size_t ) ( att [ i ] - > attlen ) ) ;
}
data = ( char * ) att_addlength ( ( long ) data , att [ i ] - > attlen , value [ i ] ) ;
}
}
@ -192,89 +177,6 @@ heap_attisnull(HeapTuple tup, int attnum)
return 0 ;
}
/* ----------------------------------------------------------------
* system attribute heap tuple support
* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
*/
/* ----------------
* heap_sysattrlen
*
* This routine returns the length of a system attribute .
* - - - - - - - - - - - - - - - -
*/
int
heap_sysattrlen ( AttrNumber attno )
{
HeapTupleHeader f = NULL ;
switch ( attno )
{
case TableOidAttributeNumber :
return sizeof f - > t_oid ;
case SelfItemPointerAttributeNumber :
return sizeof f - > t_ctid ;
case ObjectIdAttributeNumber :
return sizeof f - > t_oid ;
case MinTransactionIdAttributeNumber :
return sizeof f - > t_xmin ;
case MinCommandIdAttributeNumber :
return sizeof f - > t_cmin ;
case MaxTransactionIdAttributeNumber :
return sizeof f - > t_xmax ;
case MaxCommandIdAttributeNumber :
return sizeof f - > t_cmax ;
default :
elog ( ERROR , " sysattrlen: System attribute number %d unknown. " , attno ) ;
return 0 ;
}
}
/* ----------------
* heap_sysattrbyval
*
* This routine returns the " by-value " property of a system attribute .
* - - - - - - - - - - - - - - - -
*/
bool
heap_sysattrbyval ( AttrNumber attno )
{
bool byval ;
switch ( attno )
{
case TableOidAttributeNumber :
byval = true ;
break ;
case SelfItemPointerAttributeNumber :
byval = false ;
break ;
case ObjectIdAttributeNumber :
byval = true ;
break ;
case MinTransactionIdAttributeNumber :
byval = true ;
break ;
case MinCommandIdAttributeNumber :
byval = true ;
break ;
case MaxTransactionIdAttributeNumber :
byval = true ;
break ;
case MaxCommandIdAttributeNumber :
byval = true ;
break ;
default :
byval = true ;
elog ( ERROR , " sysattrbyval: System attribute number %d unknown. " ,
attno ) ;
break ;
}
return byval ;
}
/* ----------------
* nocachegetattr
*
@ -332,8 +234,7 @@ nocachegetattr(HeapTuple tuple,
/* This is handled in the macro */
if ( att [ attnum ] - > attcacheoff ! = - 1 )
{
return ( Datum )
fetchatt ( & ( att [ attnum ] ) ,
return fetchatt ( att [ attnum ] ,
( char * ) tup + tup - > t_hoff + att [ attnum ] - > attcacheoff ) ;
}
# endif
@ -397,8 +298,8 @@ nocachegetattr(HeapTuple tuple,
{
if ( att [ attnum ] - > attcacheoff ! = - 1 )
{
return ( Datum ) fetchatt ( & ( att [ attnum ] ) ,
tp + att [ attnum ] - > attcacheoff ) ;
return fetchatt ( att [ attnum ] ,
tp + att [ attnum ] - > attcacheoff ) ;
}
else if ( ! HeapTupleAllFixed ( tuple ) )
{
@ -460,7 +361,7 @@ nocachegetattr(HeapTuple tuple,
off = att_addlength ( off , att [ j ] - > attlen , tp + off ) ;
}
return ( Datum ) fetchatt ( & ( att [ attnum ] ) , tp + att [ attnum ] - > attcacheoff ) ;
return fetchatt ( att [ attnum ] , tp + att [ attnum ] - > attcacheoff ) ;
}
else
{
@ -508,10 +409,66 @@ nocachegetattr(HeapTuple tuple,
off = att_align ( off , att [ attnum ] - > attlen , att [ attnum ] - > attalign ) ;
return ( Datum ) fetchatt ( & ( att [ attnum ] ) , tp + off ) ;
return fetchatt ( att [ attnum ] , tp + off ) ;
}
}
/* ----------------
* heap_getsysattr
*
* Fetch the value of a system attribute for a tuple .
*
* This is a support routine for the heap_getattr macro . The macro
* has already determined that the attnum refers to a system attribute .
* - - - - - - - - - - - - - - - -
*/
Datum
heap_getsysattr ( HeapTuple tup , int attnum , bool * isnull )
{
Datum result ;
Assert ( tup ) ;
/* Currently, no sys attribute ever reads as NULL. */
if ( isnull )
* isnull = false ;
switch ( attnum )
{
case SelfItemPointerAttributeNumber :
/* pass-by-reference datatype */
result = PointerGetDatum ( & ( tup - > t_self ) ) ;
break ;
case ObjectIdAttributeNumber :
result = ObjectIdGetDatum ( tup - > t_data - > t_oid ) ;
break ;
case MinTransactionIdAttributeNumber :
/* XXX should have a TransactionIdGetDatum macro */
result = ( Datum ) ( tup - > t_data - > t_xmin ) ;
break ;
case MinCommandIdAttributeNumber :
/* XXX should have a CommandIdGetDatum macro */
result = ( Datum ) ( tup - > t_data - > t_cmin ) ;
break ;
case MaxTransactionIdAttributeNumber :
/* XXX should have a TransactionIdGetDatum macro */
result = ( Datum ) ( tup - > t_data - > t_xmax ) ;
break ;
case MaxCommandIdAttributeNumber :
/* XXX should have a CommandIdGetDatum macro */
result = ( Datum ) ( tup - > t_data - > t_cmax ) ;
break ;
case TableOidAttributeNumber :
result = ObjectIdGetDatum ( tup - > t_tableOid ) ;
break ;
default :
elog ( ERROR , " heap_getsysattr: invalid attnum %d " , attnum ) ;
result = 0 ; /* keep compiler quiet */
break ;
}
return result ;
}
/* ----------------
* heap_copytuple
*
@ -630,18 +587,21 @@ heap_formtuple(TupleDesc tupleDescriptor,
int i ;
int numberOfAttributes = tupleDescriptor - > natts ;
if ( numberOfAttributes > MaxHeapAttributeNumber )
elog ( ERROR , " heap_formtuple: numberOfAttributes of %d > %d " ,
numberOfAttributes , MaxHeapAttributeNumber ) ;
len = offsetof ( HeapTupleHeaderData , t_bits ) ;
for ( i = 0 ; i < numberOfAttributes & & ! hasnull ; i + + )
for ( i = 0 ; i < numberOfAttributes ; i + + )
{
if ( nulls [ i ] ! = ' ' )
{
hasnull = true ;
break ;
}
}
if ( numberOfAttributes > MaxHeapAttributeNumber )
elog ( ERROR , " heap_formtuple: numberOfAttributes of %d > %d " ,
numberOfAttributes , MaxHeapAttributeNumber ) ;
if ( hasnull )
{
bitmaplen = BITMAPLEN ( numberOfAttributes ) ;
Tom Lane
25 years ago