/* ----------------
* heap_attisnull - returns TRUE iff tuple attribute is not present
* ----------------
*/
bool
heap_attisnull(HeapTuple tup, int attnum)
{
Assert(!is_memtuple((GenericTuple) tup));
if (attnum > (int) HeapTupleHeaderGetNatts(tup->t_data))
return true;
if (attnum > 0)
{
if (HeapTupleNoNulls(tup))
return false;
return att_isnull(attnum - 1, tup->t_data->t_bits);
}
switch (attnum)
{
case TableOidAttributeNumber:
case SelfItemPointerAttributeNumber:
case ObjectIdAttributeNumber:
case MinTransactionIdAttributeNumber:
case MinCommandIdAttributeNumber:
case MaxTransactionIdAttributeNumber:
case MaxCommandIdAttributeNumber:
case GpSegmentIdAttributeNumber: /*CDB*/
/* these are never null */
break;
default:
elog(ERROR, "invalid attnum: %d", attnum);
}
return false;
}
/* ----------------
* heap_copytuple
*
* returns a copy of an entire tuple
*
* The HeapTuple struct, tuple header, and tuple data are all allocated
* as a single palloc() block.
* ----------------
*/
HeapTuple
heaptuple_copy_to(HeapTuple tuple, HeapTuple dest, uint32 *destlen)
{
HeapTuple newTuple;
uint32 len;
if (!HeapTupleIsValid(tuple) || tuple->t_data == NULL)
return NULL;
Assert(!is_memtuple((GenericTuple) tuple));
len = HEAPTUPLESIZE + tuple->t_len;
if(destlen && *destlen < len)
{
*destlen = len;
return NULL;
}
if(destlen)
{
*destlen = len;
newTuple = dest;
}
else
newTuple = (HeapTuple) palloc(HEAPTUPLESIZE + tuple->t_len);
newTuple->t_len = tuple->t_len;
newTuple->t_self = tuple->t_self;
newTuple->t_data = (HeapTupleHeader) ((char *) newTuple + HEAPTUPLESIZE);
memcpy((char *) newTuple->t_data, (char *) tuple->t_data, tuple->t_len);
return newTuple;
}
static void
writetup_heap(Tuplestorestate *state, void *tup)
{
uint32 tuplen = 0;
Size memsize = 0;
if (is_memtuple((GenericTuple) tup))
tuplen = memtuple_get_size((MemTuple) tup);
else
{
Assert(!is_heaptuple_splitter((HeapTuple) tup));
tuplen = heaptuple_get_size((HeapTuple) tup);
}
if (BufFileWrite(state->myfile, (void *) tup, tuplen) != (size_t) tuplen)
elog(ERROR, "write failed");
if (state->backward) /* need trailing length word? */
if (BufFileWrite(state->myfile, (void *) &tuplen,
sizeof(tuplen)) != sizeof(tuplen))
elog(ERROR, "write failed");
memsize = GetMemoryChunkSpace(tup);
state->spilledBytes += memsize;
FREEMEM(state, memsize);
pfree(tup);
}
/*
* tuplestore_gettupleslot - exported function to fetch a tuple into a slot
*
* If successful, put tuple in slot and return TRUE; else, clear the slot
* and return FALSE.
*
* If copy is TRUE, the slot receives a copied tuple (allocated in current
* memory context) that will stay valid regardless of future manipulations of
* the tuplestore's state. If copy is FALSE, the slot may just receive a
* pointer to a tuple held within the tuplestore. The latter is more
* efficient but the slot contents may be corrupted if additional writes to
* the tuplestore occur. (If using tuplestore_trim, see comments therein.)
*/
bool
tuplestore_gettupleslot(Tuplestorestate *state, bool forward,
bool copy, TupleTableSlot *slot)
{
GenericTuple tuple;
bool should_free;
tuple = tuplestore_gettuple(state, forward, &should_free);
if (tuple)
{
if (copy && !should_free)
{
if (is_memtuple(tuple))
tuple = (GenericTuple) memtuple_copy_to((MemTuple) tuple, NULL, NULL);
else
tuple = (GenericTuple) heap_copytuple((HeapTuple) tuple);
should_free = true;
}
ExecStoreGenericTuple(tuple, slot, should_free);
return true;
}
else
{
ExecClearTuple(slot);
return false;
}
}
/*
* heap_modify_tuple
* form a new tuple from an old tuple and a set of replacement values.
*
* The replValues, replIsnull, and doReplace arrays must be of the length
* indicated by tupleDesc->natts. The new tuple is constructed using the data
* from replValues/replIsnull at columns where doReplace is true, and using
* the data from the old tuple at columns where doReplace is false.
*
* The result is allocated in the current memory context.
*/
HeapTuple
heap_modify_tuple(HeapTuple tuple,
TupleDesc tupleDesc,
Datum *replValues,
bool *replIsnull,
bool *doReplace)
{
int numberOfAttributes = tupleDesc->natts;
int attoff;
Datum *values;
bool *isnull;
HeapTuple newTuple;
Assert(!is_memtuple((GenericTuple) tuple));
/*
* allocate and fill values and isnull arrays from either the tuple or the
* repl information, as appropriate.
*
* NOTE: it's debatable whether to use heap_deform_tuple() here or just
* heap_getattr() only the non-replaced colums. The latter could win if
* there are many replaced columns and few non-replaced ones. However,
* heap_deform_tuple costs only O(N) while the heap_getattr way would cost
* O(N^2) if there are many non-replaced columns, so it seems better to
* err on the side of linear cost.
*/
values = (Datum *) palloc(numberOfAttributes * sizeof(Datum));
isnull = (bool *) palloc(numberOfAttributes * sizeof(bool));
heap_deform_tuple(tuple, tupleDesc, values, isnull);
for (attoff = 0; attoff < numberOfAttributes; attoff++)
{
if (doReplace[attoff])
{
values[attoff] = replValues[attoff];
isnull[attoff] = replIsnull[attoff];
}
}
/*
* create a new tuple from the values and isnull arrays
*/
newTuple = heap_form_tuple(tupleDesc, values, isnull);
pfree(values);
pfree(isnull);
/*
* copy the identification info of the old tuple: t_ctid, t_self, and OID
* (if any)
*/
newTuple->t_data->t_ctid = tuple->t_data->t_ctid;
newTuple->t_self = tuple->t_self;
if (tupleDesc->tdhasoid)
HeapTupleSetOid(newTuple, HeapTupleGetOid(tuple));
return newTuple;
}
static void *
copytup_heap(Tuplestorestate *state, void *tup)
{
if (!is_memtuple((GenericTuple) tup))
return heaptuple_copy_to((HeapTuple) tup, NULL, NULL);
else
return memtuple_copy_to((MemTuple) tup, NULL, NULL);
}
/* ----------------
* 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);
Assert(!is_memtuple((GenericTuple) 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(HeapTupleGetOid(tup));
break;
case MinTransactionIdAttributeNumber:
result = TransactionIdGetDatum(HeapTupleHeaderGetXmin(tup->t_data));
break;
case MaxTransactionIdAttributeNumber:
result = TransactionIdGetDatum(HeapTupleHeaderGetXmax(tup->t_data));
break;
case MinCommandIdAttributeNumber:
case MaxCommandIdAttributeNumber:
/*
* cmin and cmax are now both aliases for the same field, which
* can in fact also be a combo command id. XXX perhaps we should
* return the "real" cmin or cmax if possible, that is if we are
* inside the originating transaction?
*/
result = CommandIdGetDatum(HeapTupleHeaderGetRawCommandId(tup->t_data));
break;
case TableOidAttributeNumber:
/* CDB: Must now use a TupleTableSlot to access the 'tableoid'. */
result = ObjectIdGetDatum(InvalidOid);
elog(ERROR, "Invalid reference to \"tableoid\" system attribute");
break;
case GpSegmentIdAttributeNumber: /*CDB*/
result = Int32GetDatum(Gp_segment);
break;
default:
elog(ERROR, "invalid attnum: %d", attnum);
result = 0; /* keep compiler quiet */
break;
}
return result;
}
/* ----------------
* heap_copytuple_with_tuple
*
* copy a tuple into a caller-supplied HeapTuple management struct
*
* Note that after calling this function, the "dest" HeapTuple will not be
* allocated as a single palloc() block (unlike with heap_copytuple()).
* ----------------
*/
void
heap_copytuple_with_tuple(HeapTuple src, HeapTuple dest)
{
if (!HeapTupleIsValid(src) || src->t_data == NULL)
{
dest->t_data = NULL;
return;
}
Assert(!is_memtuple((GenericTuple) src));
dest->t_len = src->t_len;
dest->t_self = src->t_self;
dest->t_data = (HeapTupleHeader) palloc(src->t_len);
memcpy((char *) dest->t_data, (char *) src->t_data, src->t_len);
}
/*
* Serialize a tuple directly into a buffer.
*
* We're called with at least enough space for a tuple-chunk-header.
*/
int
SerializeTupleDirect(GenericTuple gtuple, SerTupInfo *pSerInfo, struct directTransportBuffer *b)
{
int natts;
int dataSize = TUPLE_CHUNK_HEADER_SIZE;
TupleDesc tupdesc;
AssertArg(gtuple != NULL);
AssertArg(pSerInfo != NULL);
AssertArg(b != NULL);
tupdesc = pSerInfo->tupdesc;
natts = tupdesc->natts;
do
{
if (natts == 0)
{
/* TC_EMTPY is just one chunk */
SetChunkType(b->pri, TC_EMPTY);
SetChunkDataSize(b->pri, 0);
break;
}
/* easy case */
if (is_memtuple(gtuple))
{
MemTuple tuple = (MemTuple) gtuple;
int tupleSize;
int paddedSize;
tupleSize = memtuple_get_size(tuple);
paddedSize = TYPEALIGN(TUPLE_CHUNK_ALIGN, tupleSize);
if (paddedSize + TUPLE_CHUNK_HEADER_SIZE > b->prilen)
return 0;
/* will fit. */
memcpy(b->pri + TUPLE_CHUNK_HEADER_SIZE, tuple, tupleSize);
memset(b->pri + TUPLE_CHUNK_HEADER_SIZE + tupleSize, 0, paddedSize - tupleSize);
dataSize += paddedSize;
SetChunkType(b->pri, TC_WHOLE);
SetChunkDataSize(b->pri, dataSize - TUPLE_CHUNK_HEADER_SIZE);
break;
}
else
{
HeapTuple tuple = (HeapTuple) gtuple;
TupSerHeader tsh;
unsigned int datalen;
unsigned int nullslen;
HeapTupleHeader t_data = tuple->t_data;
unsigned char *pos;
datalen = tuple->t_len - t_data->t_hoff;
if (HeapTupleHasNulls(tuple))
nullslen = BITMAPLEN(HeapTupleHeaderGetNatts(t_data));
else
nullslen = 0;
tsh.tuplen = sizeof(TupSerHeader) + TYPEALIGN(TUPLE_CHUNK_ALIGN, nullslen) + TYPEALIGN(TUPLE_CHUNK_ALIGN, datalen);
tsh.natts = HeapTupleHeaderGetNatts(t_data);
tsh.infomask = t_data->t_infomask;
if (dataSize + tsh.tuplen > b->prilen ||
(tsh.infomask & HEAP_HASEXTERNAL) != 0)
return 0;
pos = b->pri + TUPLE_CHUNK_HEADER_SIZE;
memcpy(pos, (char *)&tsh, sizeof(TupSerHeader));
pos += sizeof(TupSerHeader);
if (nullslen)
{
memcpy(pos, (char *)t_data->t_bits, nullslen);
pos += nullslen;
memset(pos, 0, TYPEALIGN(TUPLE_CHUNK_ALIGN, nullslen) - nullslen);
pos += TYPEALIGN(TUPLE_CHUNK_ALIGN, nullslen) - nullslen;
}
memcpy(pos, (char *)t_data + t_data->t_hoff, datalen);
pos += datalen;
memset(pos, 0, TYPEALIGN(TUPLE_CHUNK_ALIGN, datalen) - datalen);
pos += TYPEALIGN(TUPLE_CHUNK_ALIGN, datalen) - datalen;
dataSize += tsh.tuplen;
SetChunkType(b->pri, TC_WHOLE);
SetChunkDataSize(b->pri, dataSize - TUPLE_CHUNK_HEADER_SIZE);
break;
}
/* tuple that we can't handle here (big ?) -- do the older "out-of-line" serialization */
return 0;
}
while (0);
return dataSize;
}
/*
* Convert a HeapTuple into a byte-sequence, and store it directly
* into a chunklist for transmission.
*
* This code is based on the printtup_internal_20() function in printtup.c.
*/
void
SerializeTupleIntoChunks(GenericTuple gtuple, SerTupInfo *pSerInfo, TupleChunkList tcList)
{
TupleChunkListItem tcItem = NULL;
MemoryContext oldCtxt;
TupleDesc tupdesc;
int i,
natts;
AssertArg(tcList != NULL);
AssertArg(gtuple != NULL);
AssertArg(pSerInfo != NULL);
tupdesc = pSerInfo->tupdesc;
natts = tupdesc->natts;
/* get ready to go */
tcList->p_first = NULL;
tcList->p_last = NULL;
tcList->num_chunks = 0;
tcList->serialized_data_length = 0;
tcList->max_chunk_length = Gp_max_tuple_chunk_size;
if (natts == 0)
{
tcItem = getChunkFromCache(&pSerInfo->chunkCache);
if (tcItem == NULL)
{
ereport(FATAL, (errcode(ERRCODE_OUT_OF_MEMORY),
errmsg("Could not allocate space for first chunk item in new chunk list.")));
}
/* TC_EMTPY is just one chunk */
SetChunkType(tcItem->chunk_data, TC_EMPTY);
tcItem->chunk_length = TUPLE_CHUNK_HEADER_SIZE;
appendChunkToTCList(tcList, tcItem);
return;
}
tcItem = getChunkFromCache(&pSerInfo->chunkCache);
if (tcItem == NULL)
{
ereport(FATAL, (errcode(ERRCODE_OUT_OF_MEMORY),
errmsg("Could not allocate space for first chunk item in new chunk list.")));
}
/* assume that we'll take a single chunk */
SetChunkType(tcItem->chunk_data, TC_WHOLE);
tcItem->chunk_length = TUPLE_CHUNK_HEADER_SIZE;
appendChunkToTCList(tcList, tcItem);
AssertState(s_tupSerMemCtxt != NULL);
if (is_memtuple(gtuple))
{
MemTuple mtuple = (MemTuple) gtuple;
addByteStringToChunkList(tcList, (char *) mtuple, memtuple_get_size(mtuple), &pSerInfo->chunkCache);
addPadding(tcList, &pSerInfo->chunkCache, memtuple_get_size(mtuple));
}
else
{
HeapTuple tuple = (HeapTuple) gtuple;
HeapTupleHeader t_data = tuple->t_data;
TupSerHeader tsh;
unsigned int datalen;
unsigned int nullslen;
datalen = tuple->t_len - t_data->t_hoff;
if (HeapTupleHasNulls(tuple))
nullslen = BITMAPLEN(HeapTupleHeaderGetNatts(t_data));
else
nullslen = 0;
tsh.tuplen = sizeof(TupSerHeader) + TYPEALIGN(TUPLE_CHUNK_ALIGN,nullslen) + datalen;
tsh.natts = HeapTupleHeaderGetNatts(t_data);
tsh.infomask = t_data->t_infomask;
addByteStringToChunkList(tcList, (char *)&tsh, sizeof(TupSerHeader), &pSerInfo->chunkCache);
/* If we don't have any attributes which have been toasted, we
* can be very very simple: just send the raw data. */
if ((tsh.infomask & HEAP_HASEXTERNAL) == 0)
{
if (nullslen)
{
addByteStringToChunkList(tcList, (char *)t_data->t_bits, nullslen, &pSerInfo->chunkCache);
addPadding(tcList,&pSerInfo->chunkCache,nullslen);
}
addByteStringToChunkList(tcList, (char *)t_data + t_data->t_hoff, datalen, &pSerInfo->chunkCache);
addPadding(tcList,&pSerInfo->chunkCache,datalen);
}
else
{
/* We have to be more careful when we have tuples that
* have been toasted. Ideally we'd like to send the
* untoasted attributes in as "raw" a format as possible
* but that makes rebuilding the tuple harder .
*/
oldCtxt = MemoryContextSwitchTo(s_tupSerMemCtxt);
/* deconstruct the tuple (faster than a heap_getattr loop) */
heap_deform_tuple(tuple, tupdesc, pSerInfo->values, pSerInfo->nulls);
MemoryContextSwitchTo(oldCtxt);
/* Send the nulls character-array. */
addByteStringToChunkList(tcList, pSerInfo->nulls, natts, &pSerInfo->chunkCache);
addPadding(tcList,&pSerInfo->chunkCache,natts);
/*
* send the attributes of this tuple: NOTE anything which allocates
* temporary space (e.g. could result in a PG_DETOAST_DATUM) should be
* executed with the memory context set to s_tupSerMemCtxt
*/
for (i = 0; i < natts; ++i)
{
SerAttrInfo *attrInfo = pSerInfo->myinfo + i;
Datum origattr = pSerInfo->values[i],
attr;
/* skip null attributes (already taken care of above) */
if (pSerInfo->nulls[i])
continue;
if (attrInfo->typlen == -1)
{
int32 sz;
char *data;
/*
* If we have a toasted datum, forcibly detoast it here to avoid
* memory leakage: we want to force the detoast allocation(s) to
* happen in our reset-able serialization context.
*/
oldCtxt = MemoryContextSwitchTo(s_tupSerMemCtxt);
attr = PointerGetDatum(PG_DETOAST_DATUM_PACKED(origattr));
MemoryContextSwitchTo(oldCtxt);
sz = VARSIZE_ANY_EXHDR(attr);
data = VARDATA_ANY(attr);
/* Send length first, then data */
addInt32ToChunkList(tcList, sz, &pSerInfo->chunkCache);
addByteStringToChunkList(tcList, data, sz, &pSerInfo->chunkCache);
addPadding(tcList, &pSerInfo->chunkCache, sz);
}
else if (attrInfo->typlen == -2)
{
int32 sz;
char *data;
/* CString, we would send the string with the terminating '\0' */
data = DatumGetCString(origattr);
sz = strlen(data) + 1;
/* Send length first, then data */
addInt32ToChunkList(tcList, sz, &pSerInfo->chunkCache);
addByteStringToChunkList(tcList, data, sz, &pSerInfo->chunkCache);
addPadding(tcList, &pSerInfo->chunkCache, sz);
}
else if (attrInfo->typbyval)
{
/*
* We send a full-width Datum for all pass-by-value types, regardless of
* the actual size.
*/
addByteStringToChunkList(tcList, (char *) &origattr, sizeof(Datum), &pSerInfo->chunkCache);
addPadding(tcList, &pSerInfo->chunkCache, sizeof(Datum));
}
else
{
addByteStringToChunkList(tcList, DatumGetPointer(origattr), attrInfo->typlen, &pSerInfo->chunkCache);
addPadding(tcList, &pSerInfo->chunkCache, attrInfo->typlen);
attr = origattr;
}
}
MemoryContextReset(s_tupSerMemCtxt);
}
}
/*
* if we have more than 1 chunk we have to set the chunk types on our
* first chunk and last chunk
*/
if (tcList->num_chunks > 1)
{
TupleChunkListItem first,
last;
first = tcList->p_first;
last = tcList->p_last;
Assert(first != NULL);
Assert(first != last);
Assert(last != NULL);
SetChunkType(first->chunk_data, TC_PARTIAL_START);
SetChunkType(last->chunk_data, TC_PARTIAL_END);
/*
* any intervening chunks are already set to TC_PARTIAL_MID when
* allocated
*/
}
return;
}
/*
* heap_deform_tuple
* Given a tuple, extract data into values/isnull arrays; this is
* the inverse of heap_form_tuple.
*
* Storage for the values/isnull arrays is provided by the caller;
* it should be sized according to tupleDesc->natts not tuple->t_natts.
*
* Note that for pass-by-reference datatypes, the pointer placed
* in the Datum will point into the given tuple.
*
* When all or most of a tuple's fields need to be extracted,
* this routine will be significantly quicker than a loop around
* heap_getattr; the loop will become O(N^2) as soon as any
* noncacheable attribute offsets are involved.
*/
void
heap_deform_tuple(HeapTuple tuple, TupleDesc tupleDesc,
Datum *values, bool *isnull)
{
HeapTupleHeader tup = tuple->t_data;
bool hasnulls = HeapTupleHasNulls(tuple);
Form_pg_attribute *att = tupleDesc->attrs;
int tdesc_natts = tupleDesc->natts;
int natts; /* number of atts to extract */
int attnum;
char *tp; /* ptr to tuple data */
long off; /* offset in tuple data */
bits8 *bp = tup->t_bits; /* ptr to null bitmap in tuple */
bool slow = false; /* can we use/set attcacheoff? */
Assert(!is_memtuple((GenericTuple) tuple));
natts = HeapTupleHeaderGetNatts(tup);
/*
* In inheritance situations, it is possible that the given tuple actually
* has more fields than the caller is expecting. Don't run off the end of
* the caller's arrays.
*/
natts = Min(natts, tdesc_natts);
tp = (char *) tup + tup->t_hoff;
off = 0;
for (attnum = 0; attnum < natts; attnum++)
{
Form_pg_attribute thisatt = att[attnum];
if (hasnulls && att_isnull(attnum, bp))
{
values[attnum] = (Datum) 0;
isnull[attnum] = true;
slow = true; /* can't use attcacheoff anymore */
continue;
}
isnull[attnum] = false;
if (!slow && thisatt->attcacheoff >= 0)
off = thisatt->attcacheoff;
else if (thisatt->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 (!slow &&
off == att_align_nominal(off, thisatt->attalign))
thisatt->attcacheoff = off;
else
{
off = att_align_pointer(off, thisatt->attalign, -1,
tp + off);
slow = true;
}
}
else
{
/* not varlena, so safe to use att_align_nominal */
off = att_align_nominal(off, thisatt->attalign);
if (!slow)
thisatt->attcacheoff = off;
}
if (!slow && thisatt->attlen < 0)
slow = true;
values[attnum] = fetchatt(thisatt, tp + off);
off = att_addlength_pointer(off, thisatt->attlen, tp + off);
}
/*
* If tuple doesn't have all the atts indicated by tupleDesc, read the
* rest as null
*/
for (; attnum < tdesc_natts; attnum++)
{
values[attnum] = (Datum) 0;
isnull[attnum] = true;
}
}
/*
* heap_form_tuple
* construct a tuple from the given values[] and isnull[] arrays,
* which are of the length indicated by tupleDescriptor->natts
*
* The result is allocated in the current memory context.
*/
HeapTuple
heaptuple_form_to(TupleDesc tupleDescriptor, Datum *values, bool *isnull, HeapTuple dst, uint32 *dstlen)
{
HeapTuple tuple; /* return tuple */
HeapTupleHeader td; /* tuple data */
Size actual_len;
Size len,
data_len;
int hoff;
bool hasnull = false;
Form_pg_attribute *att = tupleDescriptor->attrs;
int numberOfAttributes = tupleDescriptor->natts;
int i;
if (numberOfAttributes > MaxTupleAttributeNumber)
ereport(ERROR,
(errcode(ERRCODE_TOO_MANY_COLUMNS),
errmsg("number of columns (%d) exceeds limit (%d)",
numberOfAttributes, MaxTupleAttributeNumber)));
/*
* Check for nulls and embedded tuples; expand any toasted attributes in
* embedded tuples. This preserves the invariant that toasting can only
* go one level deep.
*
* We can skip calling toast_flatten_tuple_attribute() if the attribute
* couldn't possibly be of composite type. All composite datums are
* varlena and have alignment 'd'; furthermore they aren't arrays. Also,
* if an attribute is already toasted, it must have been sent to disk
* already and so cannot contain toasted attributes.
*/
for (i = 0; i < numberOfAttributes; i++)
{
if (isnull[i])
hasnull = true;
else if (att[i]->attlen == -1 &&
att[i]->attalign == 'd' &&
att[i]->attndims == 0 &&
!VARATT_IS_EXTENDED(DatumGetPointer(values[i])))
{
values[i] = toast_flatten_tuple_attribute(values[i],
att[i]->atttypid,
att[i]->atttypmod);
}
}
/*
* Determine total space needed
*/
len = offsetof(HeapTupleHeaderData, t_bits);
if (hasnull)
len += BITMAPLEN(numberOfAttributes);
if (tupleDescriptor->tdhasoid)
len += sizeof(Oid);
hoff = len = MAXALIGN(len); /* align user data safely */
data_len = heap_compute_data_size(tupleDescriptor, values, isnull);
len += data_len;
if (dstlen && (*dstlen) < (HEAPTUPLESIZE + len))
{
*dstlen = HEAPTUPLESIZE + len;
return NULL;
}
if (dstlen)
{
*dstlen = HEAPTUPLESIZE + len;
tuple = dst;
memset(tuple, 0, HEAPTUPLESIZE + len);
}
else
tuple = (HeapTuple) palloc0(HEAPTUPLESIZE + len);
/*
* Allocate and zero the space needed. Note that the tuple body and
* HeapTupleData management structure are allocated in one chunk.
*/
tuple->t_data = td = (HeapTupleHeader) ((char *) tuple + HEAPTUPLESIZE);
/*
* And fill in the information. Note we fill the Datum fields even though
* this tuple may never become a Datum.
*/
tuple->t_len = len;
ItemPointerSetInvalid(&(tuple->t_self));
HeapTupleHeaderSetDatumLength(td, len);
HeapTupleHeaderSetTypeId(td, tupleDescriptor->tdtypeid);
HeapTupleHeaderSetTypMod(td, tupleDescriptor->tdtypmod);
HeapTupleHeaderSetNatts(td, numberOfAttributes);
td->t_hoff = hoff;
if (tupleDescriptor->tdhasoid) /* else leave infomask = 0 */
td->t_infomask = HEAP_HASOID;
actual_len = heap_fill_tuple(tupleDescriptor,
values,
isnull,
(char *) td + hoff,
data_len,
&td->t_infomask,
(hasnull ? td->t_bits : NULL));
Assert(data_len == actual_len);
Assert(!is_memtuple((GenericTuple) tuple));
return tuple;
}
/* ----------------
* nocachegetattr
*
* This only gets called from fastgetattr() macro, in cases where
* we can't use a cacheoffset and the value is not null.
*
* This caches attribute offsets in the attribute descriptor.
*
* An alternative way to speed things up would be to cache offsets
* with the tuple, but that seems more difficult unless you take
* the storage hit of actually putting those offsets into the
* tuple you send to disk. Yuck.
*
* This scheme will be slightly slower than that, but should
* perform well for queries which hit large #'s of tuples. After
* you cache the offsets once, examining all the other tuples using
* the same attribute descriptor will go much quicker. -cim 5/4/91
*
* NOTE: if you need to change this code, see also heap_deform_tuple.
* Also see nocache_index_getattr, which is the same code for index
* tuples.
* ----------------
*/
Datum
nocachegetattr(HeapTuple tuple,
int attnum,
TupleDesc tupleDesc)
{
HeapTupleHeader tup = tuple->t_data;
Form_pg_attribute *att = tupleDesc->attrs;
char *tp; /* ptr to data part of tuple */
bits8 *bp = tup->t_bits; /* ptr to null bitmap in tuple */
bool slow = false; /* do we have to walk attrs? */
int off; /* current offset within data */
Assert(!is_memtuple((GenericTuple) tuple));
/* ----------------
* 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.
* ----------------
*/
#ifdef IN_MACRO
/* This is handled in the macro */
Assert(attnum > 0);
if (isnull)
*isnull = false;
#endif
attnum--;
if (HeapTupleNoNulls(tuple))
{
#ifdef IN_MACRO
/* This is handled in the macro */
if (att[attnum]->attcacheoff >= 0)
{
return fetchatt(att[attnum],
(char *) tup + tup->t_hoff +
att[attnum]->attcacheoff);
}
#endif
}
else
{
/*
* there's a null somewhere in the tuple
*
* check to see if desired att is null
*/
#ifdef IN_MACRO
/* This is handled in the macro */
if (att_isnull(attnum, bp))
{
if (isnull)
*isnull = true;
return (Datum) NULL;
}
#endif
/*
* 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 + tup->t_hoff;
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.
*/
if (HeapTupleHasVarWidth(tuple))
{
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;
/* this is always true */
att[0]->attcacheoff = 0;
/*
* 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 (HeapTupleHasNulls(tuple) && 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);
}
