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itup.h File Reference
#include "access/tupdesc.h"
#include "access/tupmacs.h"
#include "storage/bufpage.h"
#include "storage/itemptr.h"
Include dependency graph for itup.h:
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Data Structures

struct  IndexTupleData
struct  IndexAttributeBitMapData

Macros

#define INDEX_SIZE_MASK   0x1FFF
#define INDEX_VAR_MASK   0x4000
#define INDEX_NULL_MASK   0x8000
#define IndexTupleSize(itup)   ((Size) (((IndexTuple) (itup))->t_info & INDEX_SIZE_MASK))
#define IndexTupleDSize(itup)   ((Size) ((itup).t_info & INDEX_SIZE_MASK))
#define IndexTupleHasNulls(itup)   ((((IndexTuple) (itup))->t_info & INDEX_NULL_MASK))
#define IndexTupleHasVarwidths(itup)   ((((IndexTuple) (itup))->t_info & INDEX_VAR_MASK))
#define IndexInfoFindDataOffset(t_info)
#define index_getattr(tup, attnum, tupleDesc, isnull)
#define MaxIndexTuplesPerPage

Typedefs

typedef struct IndexTupleData IndexTupleData
typedef IndexTupleDataIndexTuple
typedef struct
IndexAttributeBitMapData 
IndexAttributeBitMapData
typedef IndexAttributeBitMapDataIndexAttributeBitMap

Functions

IndexTuple index_form_tuple (TupleDesc tupleDescriptor, Datum *values, bool *isnull)
Datum nocache_index_getattr (IndexTuple tup, int attnum, TupleDesc tupleDesc)
void index_deform_tuple (IndexTuple tup, TupleDesc tupleDescriptor, Datum *values, bool *isnull)
IndexTuple CopyIndexTuple (IndexTuple source)

Macro Definition Documentation

#define index_getattr (   tup,
  attnum,
  tupleDesc,
  isnull 
)
Value:
( \
AssertMacro(PointerIsValid(isnull) && (attnum) > 0), \
*(isnull) = false, \
( \
(tupleDesc)->attrs[(attnum)-1]->attcacheoff >= 0 ? \
( \
fetchatt((tupleDesc)->attrs[(attnum)-1], \
(char *) (tup) + IndexInfoFindDataOffset((tup)->t_info) \
+ (tupleDesc)->attrs[(attnum)-1]->attcacheoff) \
) \
: \
nocache_index_getattr((tup), (attnum), (tupleDesc)) \
) \
: \
( \
(att_isnull((attnum)-1, (char *)(tup) + sizeof(IndexTupleData))) ? \
( \
*(isnull) = true, \
) \
: \
( \
nocache_index_getattr((tup), (attnum), (tupleDesc)) \
) \
) \
)

Definition at line 100 of file itup.h.

Referenced by _bt_check_rowcompare(), _bt_checkkeys(), _bt_compare(), _bt_isequal(), _bt_load(), _bt_mkscankey(), _hash_checkqual(), comparetup_index_btree(), copytup_index(), gintuple_get_attrnum(), gintuple_get_key(), gistchoose(), gistDeCompressAtt(), gistindex_keytest(), gistMakeUnionItVec(), gistSplitByKey(), index_deform_tuple(), readtup_index(), and StoreIndexTuple().

#define INDEX_NULL_MASK   0x8000

Definition at line 68 of file itup.h.

Referenced by index_form_tuple(), and spgFormNodeTuple().

#define INDEX_SIZE_MASK   0x1FFF

Definition at line 65 of file itup.h.

Referenced by GinFormInteriorTuple(), GinFormTuple(), index_form_tuple(), and spgFormNodeTuple().

#define INDEX_VAR_MASK   0x4000

Definition at line 67 of file itup.h.

Referenced by index_form_tuple().

#define IndexInfoFindDataOffset (   t_info)
Value:
( \
(!((t_info) & INDEX_NULL_MASK)) ? \
( \
) \
: \
( \
) \
)

Definition at line 80 of file itup.h.

Referenced by _hash_get_indextuple_hashkey(), bt_page_items(), index_form_tuple(), and nocache_index_getattr().

#define IndexTupleDSize (   itup)    ((Size) ((itup).t_info & INDEX_SIZE_MASK))
#define IndexTupleHasNulls (   itup)    ((((IndexTuple) (itup))->t_info & INDEX_NULL_MASK))
#define IndexTupleHasVarwidths (   itup)    ((((IndexTuple) (itup))->t_info & INDEX_VAR_MASK))

Definition at line 73 of file itup.h.

Referenced by bt_page_items(), and nocache_index_getattr().

Typedef Documentation

Definition at line 53 of file itup.h.

Function Documentation

IndexTuple CopyIndexTuple ( IndexTuple  source)

Definition at line 426 of file indextuple.c.

References IndexTupleSize, and palloc().

Referenced by _bt_buildadd(), _bt_insert_parent(), _bt_newroot(), _bt_pagedel(), and gistformdownlink().

{
IndexTuple result;
Size size;
size = IndexTupleSize(source);
result = (IndexTuple) palloc(size);
memcpy(result, source, size);
return result;
}
void index_deform_tuple ( IndexTuple  tup,
TupleDesc  tupleDescriptor,
Datum values,
bool isnull 
)

Definition at line 408 of file indextuple.c.

References Assert, i, index_getattr, INDEX_MAX_KEYS, and tupleDesc::natts.

Referenced by _bt_check_unique(), and comparetup_index_btree().

{
int i;
/* Assert to protect callers who allocate fixed-size arrays */
Assert(tupleDescriptor->natts <= INDEX_MAX_KEYS);
for (i = 0; i < tupleDescriptor->natts; i++)
{
values[i] = index_getattr(tup, i + 1, tupleDescriptor, &isnull[i]);
}
}
IndexTuple index_form_tuple ( TupleDesc  tupleDescriptor,
Datum values,
bool isnull 
)

Definition at line 34 of file indextuple.c.

References tupleDesc::attrs, DatumGetPointer, ereport, errcode(), errmsg(), ERROR, heap_compute_data_size(), heap_fill_tuple(), HEAP_HASVARWIDTH, heap_tuple_fetch_attr(), i, INDEX_MAX_KEYS, INDEX_NULL_MASK, INDEX_SIZE_MASK, INDEX_VAR_MASK, IndexInfoFindDataOffset, MAXALIGN, tupleDesc::natts, NULL, palloc0(), pfree(), PointerGetDatum, IndexTupleData::t_info, toast_compress_datum(), TOAST_INDEX_HACK, TOAST_INDEX_TARGET, VARATT_IS_EXTENDED, VARATT_IS_EXTERNAL, and VARSIZE.

Referenced by _hash_form_tuple(), btbuildCallback(), btinsert(), GinFormTuple(), gistFormTuple(), and storeGettuple().

{
char *tp; /* tuple pointer */
IndexTuple tuple; /* return tuple */
Size size,
data_size,
hoff;
int i;
unsigned short infomask = 0;
bool hasnull = false;
uint16 tupmask = 0;
int numberOfAttributes = tupleDescriptor->natts;
#ifdef TOAST_INDEX_HACK
Datum untoasted_values[INDEX_MAX_KEYS];
bool untoasted_free[INDEX_MAX_KEYS];
#endif
if (numberOfAttributes > INDEX_MAX_KEYS)
(errcode(ERRCODE_TOO_MANY_COLUMNS),
errmsg("number of index columns (%d) exceeds limit (%d)",
numberOfAttributes, INDEX_MAX_KEYS)));
#ifdef TOAST_INDEX_HACK
for (i = 0; i < numberOfAttributes; i++)
{
Form_pg_attribute att = tupleDescriptor->attrs[i];
untoasted_values[i] = values[i];
untoasted_free[i] = false;
/* Do nothing if value is NULL or not of varlena type */
if (isnull[i] || att->attlen != -1)
continue;
/*
* If value is stored EXTERNAL, must fetch it so we are not depending
* on outside storage. This should be improved someday.
*/
{
untoasted_values[i] =
untoasted_free[i] = true;
}
/*
* If value is above size target, and is of a compressible datatype,
* try to compress it in-line.
*/
if (!VARATT_IS_EXTENDED(DatumGetPointer(untoasted_values[i])) &&
VARSIZE(DatumGetPointer(untoasted_values[i])) > TOAST_INDEX_TARGET &&
(att->attstorage == 'x' || att->attstorage == 'm'))
{
Datum cvalue = toast_compress_datum(untoasted_values[i]);
if (DatumGetPointer(cvalue) != NULL)
{
/* successful compression */
if (untoasted_free[i])
pfree(DatumGetPointer(untoasted_values[i]));
untoasted_values[i] = cvalue;
untoasted_free[i] = true;
}
}
}
#endif
for (i = 0; i < numberOfAttributes; i++)
{
if (isnull[i])
{
hasnull = true;
break;
}
}
if (hasnull)
infomask |= INDEX_NULL_MASK;
hoff = IndexInfoFindDataOffset(infomask);
#ifdef TOAST_INDEX_HACK
data_size = heap_compute_data_size(tupleDescriptor,
untoasted_values, isnull);
#else
data_size = heap_compute_data_size(tupleDescriptor,
values, isnull);
#endif
size = hoff + data_size;
size = MAXALIGN(size); /* be conservative */
tp = (char *) palloc0(size);
tuple = (IndexTuple) tp;
heap_fill_tuple(tupleDescriptor,
untoasted_values,
#else
#endif
isnull,
(char *) tp + hoff,
data_size,
&tupmask,
(hasnull ? (bits8 *) tp + sizeof(IndexTupleData) : NULL));
#ifdef TOAST_INDEX_HACK
for (i = 0; i < numberOfAttributes; i++)
{
if (untoasted_free[i])
pfree(DatumGetPointer(untoasted_values[i]));
}
#endif
/*
* We do this because heap_fill_tuple wants to initialize a "tupmask"
* which is used for HeapTuples, but we want an indextuple infomask. The
* only relevant info is the "has variable attributes" field. We have
* already set the hasnull bit above.
*/
if (tupmask & HEAP_HASVARWIDTH)
infomask |= INDEX_VAR_MASK;
/*
* Here we make sure that the size will fit in the field reserved for it
* in t_info.
*/
if ((size & INDEX_SIZE_MASK) != size)
(errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED),
errmsg("index row requires %zu bytes, maximum size is %zu",
size, (Size) INDEX_SIZE_MASK)));
infomask |= size;
/*
* initialize metadata
*/
tuple->t_info = infomask;
return tuple;
}
Datum nocache_index_getattr ( IndexTuple  tup,
int  attnum,
TupleDesc  tupleDesc 
)

Definition at line 200 of file indextuple.c.

References Assert, att_addlength_pointer, att_align_nominal, att_align_pointer, att_isnull, tupleDesc::attrs, byte, fetchatt, i, IndexInfoFindDataOffset, IndexTupleHasNulls, IndexTupleHasVarwidths, tupleDesc::natts, NULL, and IndexTupleData::t_info.

{
Form_pg_attribute *att = tupleDesc->attrs;
char *tp; /* ptr to data part of tuple */
bits8 *bp = NULL; /* ptr to null bitmap in tuple */
bool slow = false; /* do we have to walk attrs? */
int data_off; /* tuple data offset */
int off; /* current offset within data */
/* ----------------
* Three cases:
*
* 1: No nulls and no variable-width attributes.
* 2: Has a null or a var-width AFTER att.
* 3: Has nulls or var-widths BEFORE att.
* ----------------
*/
data_off = IndexInfoFindDataOffset(tup->t_info);
attnum--;
{
/*
* there's a null somewhere in the tuple
*
* check to see if desired att is null
*/
/* XXX "knows" t_bits are just after fixed tuple header! */
bp = (bits8 *) ((char *) tup + sizeof(IndexTupleData));
/*
* Now check to see if any preceding bits are null...
*/
{
int byte = attnum >> 3;
int finalbit = attnum & 0x07;
/* check for nulls "before" final bit of last byte */
if ((~bp[byte]) & ((1 << finalbit) - 1))
slow = true;
else
{
/* check for nulls in any "earlier" bytes */
int i;
for (i = 0; i < byte; i++)
{
if (bp[i] != 0xFF)
{
slow = true;
break;
}
}
}
}
}
tp = (char *) tup + data_off;
if (!slow)
{
/*
* If we get here, there are no nulls up to and including the target
* attribute. If we have a cached offset, we can use it.
*/
if (att[attnum]->attcacheoff >= 0)
{
return fetchatt(att[attnum],
tp + att[attnum]->attcacheoff);
}
/*
* Otherwise, check for non-fixed-length attrs up to and including
* target. If there aren't any, it's safe to cheaply initialize the
* cached offsets for these attrs.
*/
{
int j;
for (j = 0; j <= attnum; j++)
{
if (att[j]->attlen <= 0)
{
slow = true;
break;
}
}
}
}
if (!slow)
{
int natts = tupleDesc->natts;
int j = 1;
/*
* If we get here, we have a tuple with no nulls or var-widths up to
* and including the target attribute, so we can use the cached offset
* ... only we don't have it yet, or we'd not have got here. Since
* it's cheap to compute offsets for fixed-width columns, we take the
* opportunity to initialize the cached offsets for *all* the leading
* fixed-width columns, in hope of avoiding future visits to this
* routine.
*/
att[0]->attcacheoff = 0;
/* we might have set some offsets in the slow path previously */
while (j < natts && att[j]->attcacheoff > 0)
j++;
off = att[j - 1]->attcacheoff + att[j - 1]->attlen;
for (; j < natts; j++)
{
if (att[j]->attlen <= 0)
break;
off = att_align_nominal(off, att[j]->attalign);
att[j]->attcacheoff = off;
off += att[j]->attlen;
}
Assert(j > attnum);
off = att[attnum]->attcacheoff;
}
else
{
bool usecache = true;
int i;
/*
* Now we know that we have to walk the tuple CAREFULLY. But we still
* might be able to cache some offsets for next time.
*
* Note - This loop is a little tricky. For each non-null attribute,
* we have to first account for alignment padding before the attr,
* then advance over the attr based on its length. Nulls have no
* storage and no alignment padding either. We can use/set
* attcacheoff until we reach either a null or a var-width attribute.
*/
off = 0;
for (i = 0;; i++) /* loop exit is at "break" */
{
if (IndexTupleHasNulls(tup) && att_isnull(i, bp))
{
usecache = false;
continue; /* this cannot be the target att */
}
/* If we know the next offset, we can skip the rest */
if (usecache && att[i]->attcacheoff >= 0)
off = att[i]->attcacheoff;
else if (att[i]->attlen == -1)
{
/*
* We can only cache the offset for a varlena attribute if the
* offset is already suitably aligned, so that there would be
* no pad bytes in any case: then the offset will be valid for
* either an aligned or unaligned value.
*/
if (usecache &&
off == att_align_nominal(off, att[i]->attalign))
att[i]->attcacheoff = off;
else
{
off = att_align_pointer(off, att[i]->attalign, -1,
tp + off);
usecache = false;
}
}
else
{
/* not varlena, so safe to use att_align_nominal */
off = att_align_nominal(off, att[i]->attalign);
if (usecache)
att[i]->attcacheoff = off;
}
if (i == attnum)
break;
off = att_addlength_pointer(off, att[i]->attlen, tp + off);
if (usecache && att[i]->attlen <= 0)
usecache = false;
}
}
return fetchatt(att[attnum], tp + off);
}