/*
* Given an opened sequence relation, lock the page buffer and find the tuple
*
* *buf receives the reference to the pinned-and-ex-locked buffer
* *seqtuple receives the reference to the sequence tuple proper
* (this arg should point to a local variable of type HeapTupleData)
*
* Function's return value points to the data payload of the tuple
*/
static Form_pg_sequence
read_seq_tuple(SeqTable elm, Relation rel, Buffer *buf, HeapTuple seqtuple)
{
Page page;
ItemId lp;
sequence_magic *sm;
Form_pg_sequence seq;
*buf = ReadBuffer(rel, 0);
LockBuffer(*buf, BUFFER_LOCK_EXCLUSIVE);
page = BufferGetPage(*buf);
sm = (sequence_magic *) PageGetSpecialPointer(page);
if (sm->magic != SEQ_MAGIC)
elog(ERROR, "bad magic number in sequence \"%s\": %08X",
RelationGetRelationName(rel), sm->magic);
lp = PageGetItemId(page, FirstOffsetNumber);
Assert(ItemIdIsNormal(lp));
/* Note we currently only bother to set these two fields of *seqtuple */
seqtuple->t_data = (HeapTupleHeader) PageGetItem(page, lp);
seqtuple->t_len = ItemIdGetLength(lp);
/*
* Previous releases of Postgres neglected to prevent SELECT FOR UPDATE on
* a sequence, which would leave a non-frozen XID in the sequence tuple's
* xmax, which eventually leads to clog access failures or worse. If we
* see this has happened, clean up after it. We treat this like a hint
* bit update, ie, don't bother to WAL-log it, since we can certainly do
* this again if the update gets lost.
*/
Assert(!(seqtuple->t_data->t_infomask & HEAP_XMAX_IS_MULTI));
if (HeapTupleHeaderGetRawXmax(seqtuple->t_data) != InvalidTransactionId)
{
HeapTupleHeaderSetXmax(seqtuple->t_data, InvalidTransactionId);
seqtuple->t_data->t_infomask &= ~HEAP_XMAX_COMMITTED;
seqtuple->t_data->t_infomask |= HEAP_XMAX_INVALID;
MarkBufferDirtyHint(*buf, true);
}
seq = (Form_pg_sequence) GETSTRUCT(seqtuple);
/* this is a handy place to update our copy of the increment */
elm->increment = seq->increment_by;
return seq;
}
/*
* Initialize a sequence's relation with the specified tuple as content
*/
static void
fill_seq_with_data(Relation rel, HeapTuple tuple)
{
Buffer buf;
Page page;
sequence_magic *sm;
OffsetNumber offnum;
/* Initialize first page of relation with special magic number */
buf = ReadBuffer(rel, P_NEW);
Assert(BufferGetBlockNumber(buf) == 0);
page = BufferGetPage(buf);
PageInit(page, BufferGetPageSize(buf), sizeof(sequence_magic));
sm = (sequence_magic *) PageGetSpecialPointer(page);
sm->magic = SEQ_MAGIC;
/* Now insert sequence tuple */
LockBuffer(buf, BUFFER_LOCK_EXCLUSIVE);
/*
* Since VACUUM does not process sequences, we have to force the tuple to
* have xmin = FrozenTransactionId now. Otherwise it would become
* invisible to SELECTs after 2G transactions. It is okay to do this
* because if the current transaction aborts, no other xact will ever
* examine the sequence tuple anyway.
*/
HeapTupleHeaderSetXmin(tuple->t_data, FrozenTransactionId);
HeapTupleHeaderSetXminFrozen(tuple->t_data);
HeapTupleHeaderSetCmin(tuple->t_data, FirstCommandId);
HeapTupleHeaderSetXmax(tuple->t_data, InvalidTransactionId);
tuple->t_data->t_infomask |= HEAP_XMAX_INVALID;
ItemPointerSet(&tuple->t_data->t_ctid, 0, FirstOffsetNumber);
/* check the comment above nextval_internal()'s equivalent call. */
if (RelationNeedsWAL(rel))
GetTopTransactionId();
START_CRIT_SECTION();
MarkBufferDirty(buf);
offnum = PageAddItem(page, (Item) tuple->t_data, tuple->t_len,
InvalidOffsetNumber, false, false);
if (offnum != FirstOffsetNumber)
elog(ERROR, "failed to add sequence tuple to page");
/* XLOG stuff */
if (RelationNeedsWAL(rel))
{
xl_seq_rec xlrec;
XLogRecPtr recptr;
XLogBeginInsert();
XLogRegisterBuffer(0, buf, REGBUF_WILL_INIT);
xlrec.node = rel->rd_node;
XLogRegisterData((char *) &xlrec, sizeof(xl_seq_rec));
XLogRegisterData((char *) tuple->t_data, tuple->t_len);
recptr = XLogInsert(RM_SEQ_ID, XLOG_SEQ_LOG);
PageSetLSN(page, recptr);
}
END_CRIT_SECTION();
UnlockReleaseBuffer(buf);
}
/**
* @brief Create LoadStatus file and load heap tuples directly.
* @return void
*/
static void
DirectWriterInsert(DirectWriter *self, HeapTuple tuple)
{
Page page;
OffsetNumber offnum;
ItemId itemId;
Item item;
LoadStatus *ls = &self->ls;
/* Compress the tuple data if needed. */
if (tuple->t_len > TOAST_TUPLE_THRESHOLD)
tuple = toast_insert_or_update(self->base.rel, tuple, NULL, 0);
BULKLOAD_PROFILE(&prof_writer_toast);
/* Assign oids if needed. */
if (self->base.rel->rd_rel->relhasoids)
{
Assert(!OidIsValid(HeapTupleGetOid(tuple)));
HeapTupleSetOid(tuple, GetNewOid(self->base.rel));
}
/* Assume the tuple has been toasted already. */
if (MAXALIGN(tuple->t_len) > MaxHeapTupleSize)
ereport(ERROR,
(errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED),
errmsg("row is too big: size %lu, maximum size %lu",
(unsigned long) tuple->t_len,
(unsigned long) MaxHeapTupleSize)));
/* Fill current page, or go to next page if the page is full. */
page = GetCurrentPage(self);
if (PageGetFreeSpace(page) < MAXALIGN(tuple->t_len) +
RelationGetTargetPageFreeSpace(self->base.rel, HEAP_DEFAULT_FILLFACTOR))
{
if (self->curblk < BLOCK_BUF_NUM - 1)
self->curblk++;
else
{
flush_pages(self);
self->curblk = 0; /* recycle from first block */
}
page = GetCurrentPage(self);
/* Initialize current block */
PageInit(page, BLCKSZ, 0);
PageSetTLI(page, ThisTimeLineID);
}
tuple->t_data->t_infomask &= ~(HEAP_XACT_MASK);
tuple->t_data->t_infomask2 &= ~(HEAP2_XACT_MASK);
tuple->t_data->t_infomask |= HEAP_XMAX_INVALID;
HeapTupleHeaderSetXmin(tuple->t_data, self->xid);
HeapTupleHeaderSetCmin(tuple->t_data, self->cid);
HeapTupleHeaderSetXmax(tuple->t_data, 0);
/* put the tuple on local page. */
offnum = PageAddItem(page, (Item) tuple->t_data,
tuple->t_len, InvalidOffsetNumber, false, true);
ItemPointerSet(&(tuple->t_self), LS_TOTAL_CNT(ls) + self->curblk, offnum);
itemId = PageGetItemId(page, offnum);
item = PageGetItem(page, itemId);
((HeapTupleHeader) item)->t_ctid = tuple->t_self;
BULKLOAD_PROFILE(&prof_writer_table);
SpoolerInsert(&self->spooler, tuple);
BULKLOAD_PROFILE(&prof_writer_index);
}
