Datum
variant_image_eq(PG_FUNCTION_ARGS)
{
Variant l = (Variant) PG_GETARG_DATUM(0);
Variant r = (Variant) PG_GETARG_DATUM(1);
int cmp;
/*
* To avoid detoasting we use _ANY variations on VAR*, but that means we must
* make sure to use VARSIZE_ANY_EXHDR, *not* VARSIZE_ANY!
*/
if(VARSIZE_ANY_EXHDR(l) != VARSIZE_ANY_EXHDR(r))
PG_RETURN_BOOL(false);
/*
* At this point we need to detoast. We could theoretically leave data
* compressed, but since there's no direct support for that we don't bother.
*/
l = (Variant) PG_DETOAST_DATUM_PACKED(l);
r = (Variant) PG_DETOAST_DATUM_PACKED(r);
cmp = memcmp(VARDATA_ANY(l), VARDATA_ANY(r), VARSIZE_ANY_EXHDR(l));
PG_FREE_IF_COPY(l, 0);
PG_FREE_IF_COPY(r, 1);
PG_RETURN_BOOL( cmp == 0 ? true : false);
}
Datum
variant_hash(PG_FUNCTION_ARGS)
{
Variant v = (Variant) PG_DETOAST_DATUM_PACKED(PG_GETARG_DATUM(0));
char *data;
int len;
Datum result;
Assert(fcinfo->flinfo->fn_strict); /* Must be strict */
data = VARDATA_ANY(v);
len = VARSIZE_ANY_EXHDR(v);
result = hash_any((unsigned char *) data, len);
/* Avoid leaking memory for toasted inputs */
PG_FREE_IF_COPY(v, 0);
return result;
}
/*
* Create an external variant from our internal representation
*/
static Variant
make_variant(VariantInt vi, FunctionCallInfo fcinfo, IOFuncSelector func)
{
VariantCache *cache;
Variant v;
bool oid_overflow=OID_TOO_LARGE(vi->typid);
long variant_length, data_length; /* long because we subtract */
Pointer data_ptr = 0;
uint flags = 0;
cache = get_cache(fcinfo, vi, func);
Assert(cache->typid = vi->typid);
#ifdef VARIANT_TEST_OID
vi->typid += OID_MASK;
oid_overflow=OID_TOO_LARGE(vi->typid);
#endif
if(vi->isnull)
{
flags |= VAR_ISNULL;
data_length = 0;
}
else if(cache->typlen == -1) /* varlena */
{
/*
* Short varlena is OK, but we need to make sure it's not external. It's OK
* to leave compressed varlena's alone too, but detoast_packed will
* uncompress them. We'll just follow rangetype.c's lead here.
*/
vi->data = PointerGetDatum( PG_DETOAST_DATUM_PACKED(vi->data) );
data_ptr = DatumGetPointer(vi->data);
/*
* Because we don't store varlena aligned or with it's header, our
* data_length is simply the varlena length.
*/
data_length = VARSIZE_ANY_EXHDR(vi->data);
data_ptr = VARDATA_ANY(data_ptr);
}
else if(cache->typlen == -2) /* cstring */
{
data_length = strlen(DatumGetCString(vi->data)); /* We don't store NUL terminator */
data_ptr = DatumGetPointer(vi->data);
}
else
{
Assert(cache->typlen >= 0);
if(cache->typbyval)
{
data_length = VHDRSZ; /* Start with header size to make sure alignment is correct */
data_length = (long) VDATAPTR_ALIGN(data_length, cache->typalign);
data_length += cache->typlen;
data_length -= VHDRSZ;
}
else /* fixed length, pass by reference */
{
data_length = cache->typlen;
data_ptr = DatumGetPointer(vi->data);
}
}
/* If typid is too large then we need an extra byte */
variant_length = VHDRSZ + data_length + (oid_overflow ? sizeof(char) : 0);
if( variant_length < 0 )
elog(ERROR, "Negative variant_length %li", variant_length);
v = palloc0(variant_length);
SET_VARSIZE(v, variant_length);
v->pOid = vi->typid;
v->typmod = vi->typmod;
if(oid_overflow)
{
flags |= VAR_OVERFLOW;
/* Reset high pOid byte to zero */
v->pOid &= 0x00FFFFFF;
/* Store high byte of OID at the end of our structure */
*((char *) v + VARSIZE(v) - 1) = vi->typid >> 24;
}
/*
* Be careful not to overwrite the valid OID data
*/
v->pOid |= flags;
Assert( get_oid(v, &flags) == vi->typid );
if(!vi->isnull)
{
if(cache->typbyval)
{
Pointer p = VDATAPTR_ALIGN(v, cache->typalign);
store_att_byval(p, vi->data, cache->typlen);
}
else
memcpy(VDATAPTR(v), data_ptr, data_length);
}
return v;
}
/*
* record_image_eq :
* compares two records for identical contents, based on byte images
* result :
* returns true if the records are identical, false otherwise.
*
* Note: we do not use record_image_cmp here, since we can avoid
* de-toasting for unequal lengths this way.
*/
Datum
record_image_eq(PG_FUNCTION_ARGS)
{
HeapTupleHeader record1 = PG_GETARG_HEAPTUPLEHEADER(0);
HeapTupleHeader record2 = PG_GETARG_HEAPTUPLEHEADER(1);
bool result = true;
Oid tupType1;
Oid tupType2;
int32 tupTypmod1;
int32 tupTypmod2;
TupleDesc tupdesc1;
TupleDesc tupdesc2;
HeapTupleData tuple1;
HeapTupleData tuple2;
int ncolumns1;
int ncolumns2;
RecordCompareData *my_extra;
int ncols;
Datum *values1;
Datum *values2;
bool *nulls1;
bool *nulls2;
int i1;
int i2;
int j;
/* Extract type info from the tuples */
tupType1 = HeapTupleHeaderGetTypeId(record1);
tupTypmod1 = HeapTupleHeaderGetTypMod(record1);
tupdesc1 = lookup_rowtype_tupdesc(tupType1, tupTypmod1);
ncolumns1 = tupdesc1->natts;
tupType2 = HeapTupleHeaderGetTypeId(record2);
tupTypmod2 = HeapTupleHeaderGetTypMod(record2);
tupdesc2 = lookup_rowtype_tupdesc(tupType2, tupTypmod2);
ncolumns2 = tupdesc2->natts;
/* Build temporary HeapTuple control structures */
tuple1.t_len = HeapTupleHeaderGetDatumLength(record1);
ItemPointerSetInvalid(&(tuple1.t_self));
tuple1.t_tableOid = InvalidOid;
tuple1.t_data = record1;
tuple2.t_len = HeapTupleHeaderGetDatumLength(record2);
ItemPointerSetInvalid(&(tuple2.t_self));
tuple2.t_tableOid = InvalidOid;
tuple2.t_data = record2;
/*
* We arrange to look up the needed comparison info just once per series
* of calls, assuming the record types don't change underneath us.
*/
ncols = Max(ncolumns1, ncolumns2);
my_extra = (RecordCompareData *) fcinfo->flinfo->fn_extra;
if (my_extra == NULL ||
my_extra->ncolumns < ncols)
{
fcinfo->flinfo->fn_extra =
MemoryContextAlloc(fcinfo->flinfo->fn_mcxt,
offsetof(RecordCompareData, columns) +
ncols * sizeof(ColumnCompareData));
my_extra = (RecordCompareData *) fcinfo->flinfo->fn_extra;
my_extra->ncolumns = ncols;
my_extra->record1_type = InvalidOid;
my_extra->record1_typmod = 0;
my_extra->record2_type = InvalidOid;
my_extra->record2_typmod = 0;
}
if (my_extra->record1_type != tupType1 ||
my_extra->record1_typmod != tupTypmod1 ||
my_extra->record2_type != tupType2 ||
my_extra->record2_typmod != tupTypmod2)
{
MemSet(my_extra->columns, 0, ncols * sizeof(ColumnCompareData));
my_extra->record1_type = tupType1;
my_extra->record1_typmod = tupTypmod1;
my_extra->record2_type = tupType2;
my_extra->record2_typmod = tupTypmod2;
}
/* Break down the tuples into fields */
values1 = (Datum *) palloc(ncolumns1 * sizeof(Datum));
nulls1 = (bool *) palloc(ncolumns1 * sizeof(bool));
heap_deform_tuple(&tuple1, tupdesc1, values1, nulls1);
values2 = (Datum *) palloc(ncolumns2 * sizeof(Datum));
nulls2 = (bool *) palloc(ncolumns2 * sizeof(bool));
heap_deform_tuple(&tuple2, tupdesc2, values2, nulls2);
/*
* Scan corresponding columns, allowing for dropped columns in different
* places in the two rows. i1 and i2 are physical column indexes, j is
* the logical column index.
*/
i1 = i2 = j = 0;
while (i1 < ncolumns1 || i2 < ncolumns2)
{
/*
* Skip dropped columns
*/
if (i1 < ncolumns1 && tupdesc1->attrs[i1]->attisdropped)
{
i1++;
continue;
}
if (i2 < ncolumns2 && tupdesc2->attrs[i2]->attisdropped)
{
i2++;
continue;
}
if (i1 >= ncolumns1 || i2 >= ncolumns2)
break; /* we'll deal with mismatch below loop */
/*
* Have two matching columns, they must be same type
*/
if (tupdesc1->attrs[i1]->atttypid !=
tupdesc2->attrs[i2]->atttypid)
ereport(ERROR,
(errcode(ERRCODE_DATATYPE_MISMATCH),
errmsg("cannot compare dissimilar column types %s and %s at record column %d",
format_type_be(tupdesc1->attrs[i1]->atttypid),
format_type_be(tupdesc2->attrs[i2]->atttypid),
j + 1)));
/*
* We consider two NULLs equal; NULL > not-NULL.
*/
if (!nulls1[i1] || !nulls2[i2])
{
if (nulls1[i1] || nulls2[i2])
{
result = false;
break;
}
/* Compare the pair of elements */
if (tupdesc1->attrs[i1]->attlen == -1)
{
Size len1,
len2;
len1 = toast_raw_datum_size(values1[i1]);
len2 = toast_raw_datum_size(values2[i2]);
/* No need to de-toast if lengths don't match. */
if (len1 != len2)
result = false;
else
{
struct varlena *arg1val;
struct varlena *arg2val;
arg1val = PG_DETOAST_DATUM_PACKED(values1[i1]);
arg2val = PG_DETOAST_DATUM_PACKED(values2[i2]);
result = (memcmp(VARDATA_ANY(arg1val),
VARDATA_ANY(arg2val),
len1 - VARHDRSZ) == 0);
/* Only free memory if it's a copy made here. */
if ((Pointer) arg1val != (Pointer) values1[i1])
pfree(arg1val);
if ((Pointer) arg2val != (Pointer) values2[i2])
pfree(arg2val);
}
}
else if (tupdesc1->attrs[i1]->attbyval)
{
switch (tupdesc1->attrs[i1]->attlen)
{
case 1:
result = (GET_1_BYTE(values1[i1]) ==
GET_1_BYTE(values2[i2]));
break;
case 2:
result = (GET_2_BYTES(values1[i1]) ==
GET_2_BYTES(values2[i2]));
break;
case 4:
result = (GET_4_BYTES(values1[i1]) ==
GET_4_BYTES(values2[i2]));
break;
#if SIZEOF_DATUM == 8
case 8:
result = (GET_8_BYTES(values1[i1]) ==
GET_8_BYTES(values2[i2]));
break;
#endif
default:
Assert(false); /* cannot happen */
}
}
else
{
result = (memcmp(DatumGetPointer(values1[i1]),
DatumGetPointer(values2[i2]),
tupdesc1->attrs[i1]->attlen) == 0);
}
if (!result)
break;
}
/* equal, so continue to next column */
i1++, i2++, j++;
}
/*
* If we didn't break out of the loop early, check for column count
* mismatch. (We do not report such mismatch if we found unequal column
* values; is that a feature or a bug?)
*/
if (result)
{
if (i1 != ncolumns1 || i2 != ncolumns2)
ereport(ERROR,
(errcode(ERRCODE_DATATYPE_MISMATCH),
errmsg("cannot compare record types with different numbers of columns")));
}
pfree(values1);
pfree(nulls1);
pfree(values2);
pfree(nulls2);
ReleaseTupleDesc(tupdesc1);
ReleaseTupleDesc(tupdesc2);
/* Avoid leaking memory when handed toasted input. */
PG_FREE_IF_COPY(record1, 0);
PG_FREE_IF_COPY(record2, 1);
PG_RETURN_BOOL(result);
}
/*
* 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;
}
