/*
* Determine size of a large object
*
* NOTE: LOs can contain gaps, just like Unix files. We actually return
* the offset of the last byte + 1.
*/
static uint32
inv_getsize(LargeObjectDesc *obj_desc)
{
bool found = false;
uint32 lastbyte = 0;
ScanKeyData skey[1];
IndexScanDesc sd;
HeapTuple tuple;
Assert(PointerIsValid(obj_desc));
open_lo_relation();
ScanKeyInit(&skey[0],
Anum_pg_largeobject_loid,
BTEqualStrategyNumber, F_OIDEQ,
ObjectIdGetDatum(obj_desc->id));
sd = index_beginscan(lo_heap_r, lo_index_r,
obj_desc->snapshot, 1, skey);
/*
* Because the pg_largeobject index is on both loid and pageno, but we
* constrain only loid, a backwards scan should visit all pages of the
* large object in reverse pageno order. So, it's sufficient to examine
* the first valid tuple (== last valid page).
*/
while ((tuple = index_getnext(sd, BackwardScanDirection)) != NULL)
{
Form_pg_largeobject data;
bytea *datafield;
bool pfreeit;
found = true;
if (HeapTupleHasNulls(tuple)) /* paranoia */
elog(ERROR, "null field found in pg_largeobject");
data = (Form_pg_largeobject) GETSTRUCT(tuple);
datafield = &(data->data); /* see note at top of file */
pfreeit = false;
if (VARATT_IS_EXTENDED(datafield))
{
datafield = (bytea *)
heap_tuple_untoast_attr((struct varlena *) datafield);
pfreeit = true;
}
lastbyte = data->pageno * LOBLKSIZE + getbytealen(datafield);
if (pfreeit)
pfree(datafield);
break;
}
index_endscan(sd);
if (!found)
ereport(ERROR,
(errcode(ERRCODE_UNDEFINED_OBJECT),
errmsg("large object %u does not exist", obj_desc->id)));
return lastbyte;
}
/*
* Determine size of a large object
*
* NOTE: LOs can contain gaps, just like Unix files. We actually return
* the offset of the last byte + 1.
*/
static uint64
inv_getsize(LargeObjectDesc *obj_desc)
{
uint64 lastbyte = 0;
ScanKeyData skey[1];
SysScanDesc sd;
HeapTuple tuple;
Assert(PointerIsValid(obj_desc));
open_lo_relation();
ScanKeyInit(&skey[0],
Anum_pg_largeobject_loid,
BTEqualStrategyNumber, F_OIDEQ,
ObjectIdGetDatum(obj_desc->id));
sd = systable_beginscan_ordered(lo_heap_r, lo_index_r,
obj_desc->snapshot, 1, skey);
/*
* Because the pg_largeobject index is on both loid and pageno, but we
* constrain only loid, a backwards scan should visit all pages of the
* large object in reverse pageno order. So, it's sufficient to examine
* the first valid tuple (== last valid page).
*/
tuple = systable_getnext_ordered(sd, BackwardScanDirection);
if (HeapTupleIsValid(tuple))
{
Form_pg_largeobject data;
bytea *datafield;
bool pfreeit;
if (HeapTupleHasNulls(tuple)) /* paranoia */
elog(ERROR, "null field found in pg_largeobject");
data = (Form_pg_largeobject) GETSTRUCT(tuple);
datafield = &(data->data); /* see note at top of file */
pfreeit = false;
if (VARATT_IS_EXTENDED(datafield))
{
datafield = (bytea *)
heap_tuple_untoast_attr((struct varlena *) datafield);
pfreeit = true;
}
lastbyte = (uint64) data->pageno * LOBLKSIZE + getbytealen(datafield);
if (pfreeit)
pfree(datafield);
}
systable_endscan_ordered(sd);
return lastbyte;
}
HeapTuple
CheckerConstraints(Checker *checker, HeapTuple tuple, int *parsing_field)
{
if (checker->has_constraints)
{
*parsing_field = 0;
/* Place tuple in tuple slot */
ExecStoreTuple(tuple, checker->slot, InvalidBuffer, false);
/* Check the constraints of the tuple */
ExecConstraints(checker->resultRelInfo, checker->slot, checker->estate);
}
else if (checker->has_not_null && HeapTupleHasNulls(tuple))
{
/*
* Even if CHECK_CONSTRAINTS is not specified, check NOT NULL constraint
*/
TupleDesc desc = checker->desc;
int i;
for (i = 0; i < desc->natts; i++)
{
if (desc->attrs[i]->attnotnull &&
att_isnull(i, tuple->t_data->t_bits))
{
*parsing_field = i + 1; /* 1 origin */
ereport(ERROR,
(errcode(ERRCODE_NOT_NULL_VIOLATION),
errmsg("null value in column \"%s\" violates not-null constraint",
NameStr(desc->attrs[i]->attname))));
}
}
}
return tuple;
}
void
inv_truncate(LargeObjectDesc *obj_desc, int len)
{
int32 pageno = (int32) (len / LOBLKSIZE);
int off;
ScanKeyData skey[2];
SysScanDesc sd;
HeapTuple oldtuple;
Form_pg_largeobject olddata;
struct
{
bytea hdr;
char data[LOBLKSIZE]; /* make struct big enough */
int32 align_it; /* ensure struct is aligned well enough */
} workbuf;
char *workb = VARDATA(&workbuf.hdr);
HeapTuple newtup;
Datum values[Natts_pg_largeobject];
bool nulls[Natts_pg_largeobject];
bool replace[Natts_pg_largeobject];
CatalogIndexState indstate;
Assert(PointerIsValid(obj_desc));
/* enforce writability because snapshot is probably wrong otherwise */
if ((obj_desc->flags & IFS_WRLOCK) == 0)
ereport(ERROR,
(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
errmsg("large object %u was not opened for writing",
obj_desc->id)));
/* check existence of the target largeobject */
if (!LargeObjectExists(obj_desc->id))
ereport(ERROR,
(errcode(ERRCODE_UNDEFINED_OBJECT),
errmsg("large object %u was already dropped", obj_desc->id)));
open_lo_relation();
indstate = CatalogOpenIndexes(lo_heap_r);
/*
* Set up to find all pages with desired loid and pageno >= target
*/
ScanKeyInit(&skey[0],
Anum_pg_largeobject_loid,
BTEqualStrategyNumber, F_OIDEQ,
ObjectIdGetDatum(obj_desc->id));
ScanKeyInit(&skey[1],
Anum_pg_largeobject_pageno,
BTGreaterEqualStrategyNumber, F_INT4GE,
Int32GetDatum(pageno));
sd = systable_beginscan_ordered(lo_heap_r, lo_index_r,
obj_desc->snapshot, 2, skey);
/*
* If possible, get the page the truncation point is in. The truncation
* point may be beyond the end of the LO or in a hole.
*/
olddata = NULL;
if ((oldtuple = systable_getnext_ordered(sd, ForwardScanDirection)) != NULL)
{
if (HeapTupleHasNulls(oldtuple)) /* paranoia */
elog(ERROR, "null field found in pg_largeobject");
olddata = (Form_pg_largeobject) GETSTRUCT(oldtuple);
Assert(olddata->pageno >= pageno);
}
/*
* If we found the page of the truncation point we need to truncate the
* data in it. Otherwise if we're in a hole, we need to create a page to
* mark the end of data.
*/
if (olddata != NULL && olddata->pageno == pageno)
{
/* First, load old data into workbuf */
bytea *datafield = &(olddata->data); /* see note at top of
* file */
bool pfreeit = false;
int pagelen;
if (VARATT_IS_EXTENDED(datafield))
{
datafield = (bytea *)
heap_tuple_untoast_attr((struct varlena *) datafield);
pfreeit = true;
}
pagelen = getbytealen(datafield);
Assert(pagelen <= LOBLKSIZE);
memcpy(workb, VARDATA(datafield), pagelen);
if (pfreeit)
pfree(datafield);
/*
* Fill any hole
*/
off = len % LOBLKSIZE;
if (off > pagelen)
MemSet(workb + pagelen, 0, off - pagelen);
/* compute length of new page */
SET_VARSIZE(&workbuf.hdr, off + VARHDRSZ);
/*
* Form and insert updated tuple
*/
memset(values, 0, sizeof(values));
memset(nulls, false, sizeof(nulls));
memset(replace, false, sizeof(replace));
values[Anum_pg_largeobject_data - 1] = PointerGetDatum(&workbuf);
replace[Anum_pg_largeobject_data - 1] = true;
newtup = heap_modify_tuple(oldtuple, RelationGetDescr(lo_heap_r),
values, nulls, replace);
simple_heap_update(lo_heap_r, &newtup->t_self, newtup);
CatalogIndexInsert(indstate, newtup);
heap_freetuple(newtup);
}
else
{
/*
* If the first page we found was after the truncation point, we're in
* a hole that we'll fill, but we need to delete the later page
* because the loop below won't visit it again.
*/
if (olddata != NULL)
{
Assert(olddata->pageno > pageno);
simple_heap_delete(lo_heap_r, &oldtuple->t_self);
}
/*
* Write a brand new page.
*
* Fill the hole up to the truncation point
*/
off = len % LOBLKSIZE;
if (off > 0)
MemSet(workb, 0, off);
/* compute length of new page */
SET_VARSIZE(&workbuf.hdr, off + VARHDRSZ);
/*
* Form and insert new tuple
*/
memset(values, 0, sizeof(values));
memset(nulls, false, sizeof(nulls));
values[Anum_pg_largeobject_loid - 1] = ObjectIdGetDatum(obj_desc->id);
values[Anum_pg_largeobject_pageno - 1] = Int32GetDatum(pageno);
values[Anum_pg_largeobject_data - 1] = PointerGetDatum(&workbuf);
newtup = heap_form_tuple(lo_heap_r->rd_att, values, nulls);
simple_heap_insert(lo_heap_r, newtup);
CatalogIndexInsert(indstate, newtup);
heap_freetuple(newtup);
}
/*
* Delete any pages after the truncation point. If the initial search
* didn't find a page, then of course there's nothing more to do.
*/
if (olddata != NULL)
{
while ((oldtuple = systable_getnext_ordered(sd, ForwardScanDirection)) != NULL)
{
simple_heap_delete(lo_heap_r, &oldtuple->t_self);
}
}
systable_endscan_ordered(sd);
CatalogCloseIndexes(indstate);
/*
* Advance command counter so that tuple updates will be seen by later
* large-object operations in this transaction.
*/
CommandCounterIncrement();
}
int
inv_write(LargeObjectDesc *obj_desc, const char *buf, int nbytes)
{
int nwritten = 0;
int n;
int off;
int len;
int32 pageno = (int32) (obj_desc->offset / LOBLKSIZE);
ScanKeyData skey[2];
SysScanDesc sd;
HeapTuple oldtuple;
Form_pg_largeobject olddata;
bool neednextpage;
bytea *datafield;
bool pfreeit;
struct
{
bytea hdr;
char data[LOBLKSIZE]; /* make struct big enough */
int32 align_it; /* ensure struct is aligned well enough */
} workbuf;
char *workb = VARDATA(&workbuf.hdr);
HeapTuple newtup;
Datum values[Natts_pg_largeobject];
bool nulls[Natts_pg_largeobject];
bool replace[Natts_pg_largeobject];
CatalogIndexState indstate;
Assert(PointerIsValid(obj_desc));
Assert(buf != NULL);
/* enforce writability because snapshot is probably wrong otherwise */
if ((obj_desc->flags & IFS_WRLOCK) == 0)
ereport(ERROR,
(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
errmsg("large object %u was not opened for writing",
obj_desc->id)));
/* check existence of the target largeobject */
if (!LargeObjectExists(obj_desc->id))
ereport(ERROR,
(errcode(ERRCODE_UNDEFINED_OBJECT),
errmsg("large object %u was already dropped", obj_desc->id)));
if (nbytes <= 0)
return 0;
open_lo_relation();
indstate = CatalogOpenIndexes(lo_heap_r);
ScanKeyInit(&skey[0],
Anum_pg_largeobject_loid,
BTEqualStrategyNumber, F_OIDEQ,
ObjectIdGetDatum(obj_desc->id));
ScanKeyInit(&skey[1],
Anum_pg_largeobject_pageno,
BTGreaterEqualStrategyNumber, F_INT4GE,
Int32GetDatum(pageno));
sd = systable_beginscan_ordered(lo_heap_r, lo_index_r,
obj_desc->snapshot, 2, skey);
oldtuple = NULL;
olddata = NULL;
neednextpage = true;
while (nwritten < nbytes)
{
/*
* If possible, get next pre-existing page of the LO. We expect the
* indexscan will deliver these in order --- but there may be holes.
*/
if (neednextpage)
{
if ((oldtuple = systable_getnext_ordered(sd, ForwardScanDirection)) != NULL)
{
if (HeapTupleHasNulls(oldtuple)) /* paranoia */
elog(ERROR, "null field found in pg_largeobject");
olddata = (Form_pg_largeobject) GETSTRUCT(oldtuple);
Assert(olddata->pageno >= pageno);
}
neednextpage = false;
}
/*
* If we have a pre-existing page, see if it is the page we want to
* write, or a later one.
*/
if (olddata != NULL && olddata->pageno == pageno)
{
/*
* Update an existing page with fresh data.
*
* First, load old data into workbuf
*/
datafield = &(olddata->data); /* see note at top of file */
pfreeit = false;
if (VARATT_IS_EXTENDED(datafield))
{
datafield = (bytea *)
heap_tuple_untoast_attr((struct varlena *) datafield);
pfreeit = true;
}
len = getbytealen(datafield);
Assert(len <= LOBLKSIZE);
memcpy(workb, VARDATA(datafield), len);
if (pfreeit)
pfree(datafield);
/*
* Fill any hole
*/
off = (int) (obj_desc->offset % LOBLKSIZE);
if (off > len)
MemSet(workb + len, 0, off - len);
/*
* Insert appropriate portion of new data
*/
n = LOBLKSIZE - off;
n = (n <= (nbytes - nwritten)) ? n : (nbytes - nwritten);
memcpy(workb + off, buf + nwritten, n);
nwritten += n;
obj_desc->offset += n;
off += n;
/* compute valid length of new page */
len = (len >= off) ? len : off;
SET_VARSIZE(&workbuf.hdr, len + VARHDRSZ);
/*
* Form and insert updated tuple
*/
memset(values, 0, sizeof(values));
memset(nulls, false, sizeof(nulls));
memset(replace, false, sizeof(replace));
values[Anum_pg_largeobject_data - 1] = PointerGetDatum(&workbuf);
replace[Anum_pg_largeobject_data - 1] = true;
newtup = heap_modify_tuple(oldtuple, RelationGetDescr(lo_heap_r),
values, nulls, replace);
simple_heap_update(lo_heap_r, &newtup->t_self, newtup);
CatalogIndexInsert(indstate, newtup);
heap_freetuple(newtup);
/*
* We're done with this old page.
*/
oldtuple = NULL;
olddata = NULL;
neednextpage = true;
}
else
{
/*
* Write a brand new page.
*
* First, fill any hole
*/
off = (int) (obj_desc->offset % LOBLKSIZE);
if (off > 0)
MemSet(workb, 0, off);
/*
* Insert appropriate portion of new data
*/
n = LOBLKSIZE - off;
n = (n <= (nbytes - nwritten)) ? n : (nbytes - nwritten);
memcpy(workb + off, buf + nwritten, n);
nwritten += n;
obj_desc->offset += n;
/* compute valid length of new page */
len = off + n;
SET_VARSIZE(&workbuf.hdr, len + VARHDRSZ);
/*
* Form and insert updated tuple
*/
memset(values, 0, sizeof(values));
memset(nulls, false, sizeof(nulls));
values[Anum_pg_largeobject_loid - 1] = ObjectIdGetDatum(obj_desc->id);
values[Anum_pg_largeobject_pageno - 1] = Int32GetDatum(pageno);
values[Anum_pg_largeobject_data - 1] = PointerGetDatum(&workbuf);
newtup = heap_form_tuple(lo_heap_r->rd_att, values, nulls);
simple_heap_insert(lo_heap_r, newtup);
CatalogIndexInsert(indstate, newtup);
heap_freetuple(newtup);
}
pageno++;
}
systable_endscan_ordered(sd);
CatalogCloseIndexes(indstate);
/*
* Advance command counter so that my tuple updates will be seen by later
* large-object operations in this transaction.
*/
CommandCounterIncrement();
return nwritten;
}
int
inv_read(LargeObjectDesc *obj_desc, char *buf, int nbytes)
{
int nread = 0;
int n;
int off;
int len;
int32 pageno = (int32) (obj_desc->offset / LOBLKSIZE);
uint32 pageoff;
ScanKeyData skey[2];
SysScanDesc sd;
HeapTuple tuple;
Assert(PointerIsValid(obj_desc));
Assert(buf != NULL);
if (nbytes <= 0)
return 0;
open_lo_relation();
ScanKeyInit(&skey[0],
Anum_pg_largeobject_loid,
BTEqualStrategyNumber, F_OIDEQ,
ObjectIdGetDatum(obj_desc->id));
ScanKeyInit(&skey[1],
Anum_pg_largeobject_pageno,
BTGreaterEqualStrategyNumber, F_INT4GE,
Int32GetDatum(pageno));
sd = systable_beginscan_ordered(lo_heap_r, lo_index_r,
obj_desc->snapshot, 2, skey);
while ((tuple = systable_getnext_ordered(sd, ForwardScanDirection)) != NULL)
{
Form_pg_largeobject data;
bytea *datafield;
bool pfreeit;
if (HeapTupleHasNulls(tuple)) /* paranoia */
elog(ERROR, "null field found in pg_largeobject");
data = (Form_pg_largeobject) GETSTRUCT(tuple);
/*
* We expect the indexscan will deliver pages in order. However,
* there may be missing pages if the LO contains unwritten "holes". We
* want missing sections to read out as zeroes.
*/
pageoff = ((uint32) data->pageno) * LOBLKSIZE;
if (pageoff > obj_desc->offset)
{
n = pageoff - obj_desc->offset;
n = (n <= (nbytes - nread)) ? n : (nbytes - nread);
MemSet(buf + nread, 0, n);
nread += n;
obj_desc->offset += n;
}
if (nread < nbytes)
{
Assert(obj_desc->offset >= pageoff);
off = (int) (obj_desc->offset - pageoff);
Assert(off >= 0 && off < LOBLKSIZE);
datafield = &(data->data); /* see note at top of file */
pfreeit = false;
if (VARATT_IS_EXTENDED(datafield))
{
datafield = (bytea *)
heap_tuple_untoast_attr((struct varlena *) datafield);
pfreeit = true;
}
len = getbytealen(datafield);
if (len > off)
{
n = len - off;
n = (n <= (nbytes - nread)) ? n : (nbytes - nread);
memcpy(buf + nread, VARDATA(datafield) + off, n);
nread += n;
obj_desc->offset += n;
}
if (pfreeit)
pfree(datafield);
}
if (nread >= nbytes)
break;
}
systable_endscan_ordered(sd);
return nread;
}
/*
* 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;
}
/* ----------------
* 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_heaptuple_memtuple(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);
}
/*
* slot_deform_tuple
* Given a TupleTableSlot, extract data from the slot's physical tuple
* into its Datum/isnull arrays. Data is extracted up through the
* natts'th column (caller must ensure this is a legal column number).
*
* This is essentially an incremental version of heap_deform_tuple:
* on each call we extract attributes up to the one needed, without
* re-computing information about previously extracted attributes.
* slot->tts_nvalid is the number of attributes already extracted.
*/
static void
slot_deform_tuple(TupleTableSlot *slot, int natts)
{
HeapTuple tuple = TupGetHeapTuple(slot);
TupleDesc tupleDesc = slot->tts_tupleDescriptor;
Datum *values = slot->PRIVATE_tts_values;
bool *isnull = slot->PRIVATE_tts_isnull;
HeapTupleHeader tup = tuple->t_data;
bool hasnulls = HeapTupleHasNulls(tuple);
Form_pg_attribute *att = tupleDesc->attrs;
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; /* can we use/set attcacheoff? */
/*
* Check whether the first call for this tuple, and initialize or restore
* loop state.
*/
attnum = slot->PRIVATE_tts_nvalid;
if (attnum == 0)
{
/* Start from the first attribute */
off = 0;
slow = false;
}
else
{
/* Restore state from previous execution */
off = slot->PRIVATE_tts_off;
slow = slot->PRIVATE_tts_slow;
}
tp = (char *) tup + tup->t_hoff;
for (; 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 it's a varlena it may or may not be aligned, so check for
* something that looks like a padding byte before aligning. If
* we're already aligned it may be the leading byte of a 4-byte
* header but then the att_align is harmless. Don't bother looking
* if it's not a varlena though.*/
if (thisatt->attlen != -1 || !tp[off])
off = att_align(off, thisatt->attalign);
if (!slow && thisatt->attlen != -1)
thisatt->attcacheoff = off;
}
if (!slow && thisatt->attlen < 0)
slow = true;
values[attnum] = fetchatt(thisatt, tp + off);
off = att_addlength(off, thisatt->attlen, PointerGetDatum(tp + off));
}
/*
* Save state for next execution
*/
slot->PRIVATE_tts_nvalid = attnum;
slot->PRIVATE_tts_off = off;
slot->PRIVATE_tts_slow = slow;
}
/*
* heap_deformtuple
*
* Given a tuple, extract data into values/nulls arrays; this is
* the inverse of heap_formtuple.
*
* Storage for the values/nulls 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.
*
* OLD API with char 'n'/' ' convention for indicating nulls.
* This is deprecated and should not be used in new code, but we keep it
* around for use by old add-on modules.
*/
void
heap_deformtuple(HeapTuple tuple,
TupleDesc tupleDesc,
Datum *values,
char *nulls)
{
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? */
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;
nulls[attnum] = 'n';
slow = true; /* can't use attcacheoff anymore */
continue;
}
nulls[attnum] = ' ';
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;
}
values[attnum] = fetchatt(thisatt, tp + off);
off = att_addlength_pointer(off, thisatt->attlen, tp + off);
if (thisatt->attlen <= 0)
slow = true; /* can't use attcacheoff anymore */
}
/*
* 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;
nulls[attnum] = 'n';
}
}
/*
* 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_heaptuple_memtuple(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);
#ifdef USE_ASSERT_CHECKING
/* Ignore attributes with dropped types */
if (thisatt->attlen == -1 && !thisatt->attisdropped)
{
Assert(VARATT_IS_SHORT(DatumGetPointer(values[attnum])) ||
!VARATT_CAN_MAKE_SHORT(DatumGetPointer(values[attnum])) ||
thisatt->atttypid == OIDVECTOROID ||
thisatt->atttypid == INT2VECTOROID ||
thisatt->atttypid >= FirstNormalObjectId);
}
#endif
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;
}
}
/*
* load_auth_entries: read pg_authid into auth_entry[]
*
* auth_info_out: pointer to auth_entry * where address to auth_entry[] should be stored
* total_roles_out: pointer to int where num of total roles should be stored
*/
static void
load_auth_entries(Relation rel_authid, auth_entry **auth_info_out, int *total_roles_out)
{
BlockNumber totalblocks;
HeapScanDesc scan;
HeapTuple tuple;
int curr_role = 0;
int total_roles = 0;
int est_rows;
auth_entry *auth_info;
/*
* Read pg_authid and fill temporary data structures. Note we must read
* all roles, even those without rolcanlogin.
*/
totalblocks = RelationGetNumberOfBlocks(rel_authid);
totalblocks = totalblocks ? totalblocks : 1;
est_rows = totalblocks * (BLCKSZ / (sizeof(HeapTupleHeaderData) + sizeof(FormData_pg_authid)));
auth_info = (auth_entry *) palloc(est_rows * sizeof(auth_entry));
scan = heap_beginscan(rel_authid, SnapshotNow, 0, NULL);
while ((tuple = heap_getnext(scan, ForwardScanDirection)) != NULL)
{
Form_pg_authid aform = (Form_pg_authid) GETSTRUCT(tuple);
HeapTupleHeader tup = tuple->t_data;
char *tp; /* ptr to tuple data */
long off; /* offset in tuple data */
bits8 *bp = tup->t_bits; /* ptr to null bitmask in tuple */
Datum datum;
if (curr_role >= est_rows)
{
est_rows *= 2;
auth_info = (auth_entry *)
repalloc(auth_info, est_rows * sizeof(auth_entry));
}
auth_info[curr_role].roleid = HeapTupleGetOid(tuple);
auth_info[curr_role].rolsuper = aform->rolsuper;
auth_info[curr_role].rolcanlogin = aform->rolcanlogin;
auth_info[curr_role].rolname = pstrdup(NameStr(aform->rolname));
auth_info[curr_role].member_of = NIL;
/*
* We can't use heap_getattr() here because during startup we will not
* have any tupdesc for pg_authid. Fortunately it's not too hard to
* work around this. rolpassword is the first possibly-null field so
* we can compute its offset directly.
*/
tp = (char *) tup + tup->t_hoff;
off = offsetof(FormData_pg_authid, rolpassword);
if (HeapTupleHasNulls(tuple) &&
att_isnull(Anum_pg_authid_rolpassword - 1, bp))
{
/* passwd is null, emit as an empty string */
auth_info[curr_role].rolpassword = pstrdup("");
}
else
{
/* assume passwd is pass-by-ref */
datum = PointerGetDatum(tp + off);
/*
* The password probably shouldn't ever be out-of-line toasted; if
* it is, ignore it, since we can't handle that in startup mode.
*/
if (VARATT_IS_EXTERNAL(DatumGetPointer(datum)))
auth_info[curr_role].rolpassword = pstrdup("");
else
auth_info[curr_role].rolpassword = DatumGetCString(DirectFunctionCall1(textout, datum));
/* assume passwd has attlen -1 */
off = att_addlength(off, -1, PointerGetDatum(tp + off));
}
if (HeapTupleHasNulls(tuple) &&
att_isnull(Anum_pg_authid_rolvaliduntil - 1, bp))
{
/* rolvaliduntil is null, emit as an empty string */
auth_info[curr_role].rolvaliduntil = pstrdup("");
}
else
{
/*
* rolvaliduntil is timestamptz, which we assume is double
* alignment and pass-by-value.
*/
off = att_align(off, 'd');
datum = fetch_att(tp + off, true, sizeof(TimestampTz));
auth_info[curr_role].rolvaliduntil = DatumGetCString(DirectFunctionCall1(timestamptz_out, datum));
}
/*
* Check for illegal characters in the user name and password.
*/
if (!name_okay(auth_info[curr_role].rolname))
{
ereport(LOG,
(errmsg("invalid role name \"%s\"",
auth_info[curr_role].rolname)));
continue;
}
if (!name_okay(auth_info[curr_role].rolpassword))
{
ereport(LOG,
(errmsg("invalid role password \"%s\"",
auth_info[curr_role].rolpassword)));
continue;
}
curr_role++;
total_roles++;
}
heap_endscan(scan);
*auth_info_out = auth_info;
*total_roles_out = total_roles;
}
/*
* 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_heaptuple_memtuple(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 it's a varlena it may or may not be aligned, so check for
* something that looks like a padding byte before aligning. If
* we're already aligned it may be the leading byte of a 4-byte
* header but then the att_align is harmless. Don't bother looking
* if it's not a varlena though.*/
if (thisatt->attlen != -1 || !tp[off])
off = att_align(off, thisatt->attalign);
if (!slow && thisatt->attlen != -1)
thisatt->attcacheoff = off;
}
if (!slow && thisatt->attlen < 0)
slow = true;
values[attnum] = fetchatt(thisatt, tp + off);
#ifdef USE_ASSERT_CHECKING
/* Ignore attributes with dropped types */
if (thisatt->attlen == -1 && !thisatt->attisdropped)
{
Assert(VARATT_IS_SHORT_D(values[attnum]) ||
!VARATT_COULD_SHORT_D(values[attnum]) ||
thisatt->atttypid == OIDVECTOROID ||
thisatt->atttypid == INT2VECTOROID ||
thisatt->atttypid >= FirstNormalObjectId);
}
#endif
off = att_addlength(off, thisatt->attlen, PointerGetDatum(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;
}
}
/* ----------------
* 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 att in tuple */
bits8 *bp = tup->t_bits; /* ptr to null bitmap in tuple */
bool slow = false; /* do we have to walk nulls? */
Assert(!is_heaptuple_memtuple(tuple));
/* If any cached offsets are there we can check that they make sense, but
* there may not be any at all, so pass -1 for the attnum we know is valid */
#ifdef IN_MACRO
/* This is handled in the macro */
Assert(attnum > 0);
if (isnull)
*isnull = false;
#endif
attnum--;
/* ----------------
* 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.
* ----------------
*/
if (HeapTupleNoNulls(tuple))
{
#ifdef IN_MACRO
/* This is handled in the macro */
if (att[attnum]->attcacheoff != -1)
{
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;
/*
* now check for any non-fixed length attrs before our attribute
*/
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;
/*
* In for(), we test <= and not < because we want to see if we can
* go past it in initializing offsets.
*/
for (j = 0; j <= attnum; j++)
{
if (att[j]->attlen <= 0)
{
slow = true;
break;
}
}
}
}
/*
* If slow is false, and we got here, we know that we have a tuple with no
* nulls or var-widths before the target attribute. If possible, we also
* want to initialize the remainder of the attribute cached offset values.
*/
if (!slow)
{
int j = 1;
long off;
int natts = HeapTupleHeaderGetNatts(tup);
/*
* 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.
*/
/* this is always true */
att[0]->attcacheoff = 0;
while (j < attnum && att[j]->attcacheoff > 0)
j++;
off = att[j - 1]->attcacheoff + att[j - 1]->attlen;
for (; j <= attnum ||
/* Can we compute more? We will probably need them */
(j < natts &&
att[j]->attcacheoff == -1 &&
(HeapTupleNoNulls(tuple) || !att_isnull(j, bp)) &&
(HeapTupleAllFixed(tuple) || att[j]->attlen > 0)); j++)
{
/* don't need to worry about shortvarlenas here since we're only
* looking at non-varlenas. Note that it's important that we check
* that the target attribute itself is a nonvarlena too since we
* can't use cached offsets for even the first varlena any more. */
off = att_align(off, att[j]->attalign);
att[j]->attcacheoff = off;
off = att_addlength(off, att[j]->attlen, PointerGetDatum(tp + off));
}
return fetchatt(att[attnum], tp + att[attnum]->attcacheoff);
}
else
{
bool usecache = true;
int off = 0;
int i;
/* this is always true */
att[0]->attcacheoff = 0;
/*
* Now we know that we have to walk the tuple CAREFULLY.
*
* 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.
*/
for (i = 0; i < attnum; i++)
{
if (HeapTupleHasNulls(tuple) && att_isnull(i, bp))
{
usecache = false;
continue;
}
/* If we know the next offset, we can skip the alignment calc */
if (usecache && att[i]->attcacheoff != -1)
off = att[i]->attcacheoff;
else
{
/* if it's a varlena it may or may not be aligned, so check for
* something that looks like a padding byte before aligning. If
* we're already aligned it may be the leading byte of a 4-byte
* header but then the att_align is harmless. Don't bother
* looking if it's not a varlena though.*/
if (att[i]->attlen != -1 || !tp[off])
off = att_align(off, att[i]->attalign);
if (usecache && att[i]->attlen != -1)
att[i]->attcacheoff = off;
}
if (att[i]->attlen < 0)
usecache = false;
off = att_addlength(off, att[i]->attlen, PointerGetDatum(tp + off));
}
if (att[attnum]->attlen != -1 || !tp[off])
off = att_align(off, att[attnum]->attalign);
return fetchatt(att[attnum], tp + off);
}
}
/*
* 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(HeapTuple tuple, SerTupInfo * pSerInfo, TupleChunkList tcList)
{
TupleChunkListItem tcItem = NULL;
MemoryContext oldCtxt;
TupleDesc tupdesc;
int i,
natts;
bool fHandled;
AssertArg(tcList != NULL);
AssertArg(tuple != 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_heaptuple_memtuple(tuple))
{
addByteStringToChunkList(tcList, (char *)tuple, memtuple_get_size((MemTuple)tuple, NULL), &pSerInfo->chunkCache);
addPadding(tcList, &pSerInfo->chunkCache, memtuple_get_size((MemTuple)tuple, NULL));
}
else
{
TupSerHeader tsh;
unsigned int datalen;
unsigned int nullslen;
HeapTupleHeader t_data = tuple->t_data;
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;
bytea *outputbytes=0;
/* skip null attributes (already taken care of above) */
if (pSerInfo->nulls[i])
continue;
/*
* 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.
*/
if (attrInfo->typisvarlena)
{
oldCtxt = MemoryContextSwitchTo(s_tupSerMemCtxt);
/* we want to detoast but leave compressed, if
* possible, but we have to handle varlena
* attributes (and others ?) differently than we
* currently do (first step is to use
* heap_tuple_fetch_attr() instead of
* PG_DETOAST_DATUM()). */
attr = PointerGetDatum(PG_DETOAST_DATUM(origattr));
MemoryContextSwitchTo(oldCtxt);
}
else
attr = origattr;
/*
* Assume that the data's output will be handled by the special IO
* code, and if not then we can handle it the slow way.
*/
fHandled = true;
switch (attrInfo->atttypid)
{
case INT4OID:
addInt32ToChunkList(tcList, DatumGetInt32(attr), &pSerInfo->chunkCache);
break;
case CHAROID:
addCharToChunkList(tcList, DatumGetChar(attr), &pSerInfo->chunkCache);
addPadding(tcList,&pSerInfo->chunkCache,1);
break;
case BPCHAROID:
case VARCHAROID:
case INT2VECTOROID: /* postgres serialization logic broken, use our own */
case OIDVECTOROID: /* postgres serialization logic broken, use our own */
case ANYARRAYOID:
{
text *pText = DatumGetTextP(attr);
int32 textSize = VARSIZE(pText) - VARHDRSZ;
addInt32ToChunkList(tcList, textSize, &pSerInfo->chunkCache);
addByteStringToChunkList(tcList, (char *) VARDATA(pText), textSize, &pSerInfo->chunkCache);
addPadding(tcList,&pSerInfo->chunkCache,textSize);
break;
}
case DATEOID:
{
DateADT date = DatumGetDateADT(attr);
addByteStringToChunkList(tcList, (char *) &date, sizeof(DateADT), &pSerInfo->chunkCache);
break;
}
case NUMERICOID:
{
/*
* Treat the numeric as a varlena variable, and just push
* the whole shebang to the output-buffer. We don't care
* about the guts of the numeric.
*/
Numeric num = DatumGetNumeric(attr);
int32 numSize = VARSIZE(num) - VARHDRSZ;
addInt32ToChunkList(tcList, numSize, &pSerInfo->chunkCache);
addByteStringToChunkList(tcList, (char *) VARDATA(num), numSize, &pSerInfo->chunkCache);
addPadding(tcList,&pSerInfo->chunkCache,numSize);
break;
}
case ACLITEMOID:
{
AclItem *aip = DatumGetAclItemP(attr);
char *outputstring;
int32 aclSize ;
outputstring = DatumGetCString(DirectFunctionCall1(aclitemout,
PointerGetDatum(aip)));
aclSize = strlen(outputstring);
addInt32ToChunkList(tcList, aclSize, &pSerInfo->chunkCache);
addByteStringToChunkList(tcList, outputstring,aclSize, &pSerInfo->chunkCache);
addPadding(tcList,&pSerInfo->chunkCache,aclSize);
break;
}
case 210: /* storage manager */
{
char *smgrstr;
int32 strsize;
smgrstr = DatumGetCString(DirectFunctionCall1(smgrout, 0));
strsize = strlen(smgrstr);
addInt32ToChunkList(tcList, strsize, &pSerInfo->chunkCache);
addByteStringToChunkList(tcList, smgrstr, strsize, &pSerInfo->chunkCache);
addPadding(tcList,&pSerInfo->chunkCache,strsize);
break;
}
default:
fHandled = false;
}
if (fHandled)
continue;
/*
* the FunctionCall2 call into the send function may result in some
* allocations which we'd like to have contained by our reset-able
* context
*/
oldCtxt = MemoryContextSwitchTo(s_tupSerMemCtxt);
/* Call the attribute type's binary input converter. */
if (attrInfo->send_finfo.fn_nargs == 1)
outputbytes =
DatumGetByteaP(FunctionCall1(&attrInfo->send_finfo,
attr));
else if (attrInfo->send_finfo.fn_nargs == 2)
outputbytes =
DatumGetByteaP(FunctionCall2(&attrInfo->send_finfo,
attr,
ObjectIdGetDatum(attrInfo->send_typio_param)));
else if (attrInfo->send_finfo.fn_nargs == 3)
outputbytes =
DatumGetByteaP(FunctionCall3(&attrInfo->send_finfo,
attr,
ObjectIdGetDatum(attrInfo->send_typio_param),
Int32GetDatum(tupdesc->attrs[i]->atttypmod)));
else
{
ereport(ERROR,
(errcode(ERRCODE_INVALID_BINARY_REPRESENTATION),
errmsg("Conversion function takes %d args",attrInfo->recv_finfo.fn_nargs)));
}
MemoryContextSwitchTo(oldCtxt);
/* We assume the result will not have been toasted */
addInt32ToChunkList(tcList, VARSIZE(outputbytes) - VARHDRSZ, &pSerInfo->chunkCache);
addByteStringToChunkList(tcList, VARDATA(outputbytes),
VARSIZE(outputbytes) - VARHDRSZ, &pSerInfo->chunkCache);
addPadding(tcList,&pSerInfo->chunkCache,VARSIZE(outputbytes) - VARHDRSZ);
/*
* this was allocated in our reset-able context, but we *are* done
* with it; and for tuples with several large columns it'd be nice to
* free the memory back to the context
*/
pfree(outputbytes);
}
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;
}
/*
* Serialize a tuple directly into a buffer.
*
* We're called with at least enough space for a tuple-chunk-header.
*/
int
SerializeTupleDirect(HeapTuple tuple, SerTupInfo * pSerInfo, struct directTransportBuffer *b)
{
int natts;
int dataSize = TUPLE_CHUNK_HEADER_SIZE;
TupleDesc tupdesc;
AssertArg(tuple != 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_heaptuple_memtuple(tuple))
{
int tupleSize;
int paddedSize;
tupleSize = memtuple_get_size((MemTuple)tuple, NULL);
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
{
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;
}
/*
* slot_deform_tuple
* Given a TupleTableSlot, extract data from the slot's physical tuple
* into its Datum/isnull arrays. Data is extracted up through the
* natts'th column (caller must ensure this is a legal column number).
*
* This is essentially an incremental version of heap_deform_tuple:
* on each call we extract attributes up to the one needed, without
* re-computing information about previously extracted attributes.
* slot->tts_nvalid is the number of attributes already extracted.
*/
static void
slot_deform_tuple(TupleTableSlot *slot, int natts)
{
HeapTuple tuple = TupGetHeapTuple(slot);
TupleDesc tupleDesc = slot->tts_tupleDescriptor;
Datum *values = slot->PRIVATE_tts_values;
bool *isnull = slot->PRIVATE_tts_isnull;
HeapTupleHeader tup = tuple->t_data;
bool hasnulls = HeapTupleHasNulls(tuple);
Form_pg_attribute *att = tupleDesc->attrs;
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; /* can we use/set attcacheoff? */
/*
* Check whether the first call for this tuple, and initialize or restore
* loop state.
*/
attnum = slot->PRIVATE_tts_nvalid;
if (attnum == 0)
{
/* Start from the first attribute */
off = 0;
slow = false;
}
else
{
/* Restore state from previous execution */
off = slot->PRIVATE_tts_off;
slow = slot->PRIVATE_tts_slow;
}
tp = (char *) tup + tup->t_hoff;
for (; 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 (thisatt->attlen <= 0)
slow = true; /* can't use attcacheoff anymore */
}
/*
* Save state for next execution
*/
slot->PRIVATE_tts_nvalid = attnum;
slot->PRIVATE_tts_off = off;
slot->PRIVATE_tts_slow = slow;
}
