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Diffstat (limited to 'src/backend/access/heap/heapam.c')
-rw-r--r--src/backend/access/heap/heapam.c87
1 files changed, 58 insertions, 29 deletions
diff --git a/src/backend/access/heap/heapam.c b/src/backend/access/heap/heapam.c
index d56d6abf2bc..49ec63658f2 100644
--- a/src/backend/access/heap/heapam.c
+++ b/src/backend/access/heap/heapam.c
@@ -8,7 +8,7 @@
*
*
* IDENTIFICATION
- * $Header: /cvsroot/pgsql/src/backend/access/heap/heapam.c,v 1.112 2001/03/22 06:16:07 momjian Exp $
+ * $Header: /cvsroot/pgsql/src/backend/access/heap/heapam.c,v 1.113 2001/03/25 23:23:58 tgl Exp $
*
*
* INTERFACE ROUTINES
@@ -2126,10 +2126,19 @@ static XLogRecPtr
log_heap_update(Relation reln, Buffer oldbuf, ItemPointerData from,
Buffer newbuf, HeapTuple newtup, bool move)
{
- char tbuf[MAXALIGN(sizeof(xl_heap_header)) + 2 * sizeof(TransactionId)];
- xl_heap_update xlrec;
- xl_heap_header *xlhdr = (xl_heap_header *) tbuf;
+ /*
+ * Note: xlhdr is declared to have adequate size and correct alignment
+ * for an xl_heap_header. However the two tids, if present at all,
+ * will be packed in with no wasted space after the xl_heap_header;
+ * they aren't necessarily aligned as implied by this struct declaration.
+ */
+ struct {
+ xl_heap_header hdr;
+ TransactionId tid1;
+ TransactionId tid2;
+ } xlhdr;
int hsize = SizeOfHeapHeader;
+ xl_heap_update xlrec;
XLogRecPtr recptr;
XLogRecData rdata[4];
Page page = BufferGetPage(newbuf);
@@ -2148,10 +2157,10 @@ log_heap_update(Relation reln, Buffer oldbuf, ItemPointerData from,
rdata[1].len = 0;
rdata[1].next = &(rdata[2]);
- xlhdr->t_oid = newtup->t_data->t_oid;
- xlhdr->t_natts = newtup->t_data->t_natts;
- xlhdr->t_hoff = newtup->t_data->t_hoff;
- xlhdr->mask = newtup->t_data->t_infomask;
+ xlhdr.hdr.t_oid = newtup->t_data->t_oid;
+ xlhdr.hdr.t_natts = newtup->t_data->t_natts;
+ xlhdr.hdr.t_hoff = newtup->t_data->t_hoff;
+ xlhdr.hdr.mask = newtup->t_data->t_infomask;
if (move) /* remember xmin & xmax */
{
TransactionId xmax;
@@ -2161,13 +2170,13 @@ log_heap_update(Relation reln, Buffer oldbuf, ItemPointerData from,
xmax = InvalidTransactionId;
else
xmax = newtup->t_data->t_xmax;
- memcpy(tbuf + hsize, &xmax, sizeof(TransactionId));
- memcpy(tbuf + hsize + sizeof(TransactionId),
+ memcpy((char *) &xlhdr + hsize, &xmax, sizeof(TransactionId));
+ memcpy((char *) &xlhdr + hsize + sizeof(TransactionId),
&(newtup->t_data->t_xmin), sizeof(TransactionId));
- hsize += (2 * sizeof(TransactionId));
+ hsize += 2 * sizeof(TransactionId);
}
rdata[2].buffer = newbuf;
- rdata[2].data = (char *) xlhdr;
+ rdata[2].data = (char *) &xlhdr;
rdata[2].len = hsize;
rdata[2].next = &(rdata[3]);
@@ -2228,13 +2237,16 @@ heap_xlog_clean(bool redo, XLogRecPtr lsn, XLogRecord *record)
if (record->xl_len > SizeOfHeapClean)
{
- char unbuf[BLCKSZ];
- OffsetNumber *unused = (OffsetNumber *) unbuf;
+ OffsetNumber unbuf[BLCKSZ/sizeof(OffsetNumber)];
+ OffsetNumber *unused = unbuf;
char *unend;
ItemId lp;
- memcpy(unbuf, (char *) xlrec + SizeOfHeapClean, record->xl_len - SizeOfHeapClean);
- unend = unbuf + (record->xl_len - SizeOfHeapClean);
+ Assert((record->xl_len - SizeOfHeapClean) <= BLCKSZ);
+ memcpy((char *) unbuf,
+ (char *) xlrec + SizeOfHeapClean,
+ record->xl_len - SizeOfHeapClean);
+ unend = (char *) unbuf + (record->xl_len - SizeOfHeapClean);
while ((char *) unused < unend)
{
@@ -2318,7 +2330,6 @@ heap_xlog_insert(bool redo, XLogRecPtr lsn, XLogRecord *record)
Buffer buffer;
Page page;
OffsetNumber offnum;
- HeapTupleHeader htup;
if (redo && (record->xl_info & XLR_BKP_BLOCK_1))
return;
@@ -2338,7 +2349,11 @@ heap_xlog_insert(bool redo, XLogRecPtr lsn, XLogRecord *record)
if (redo)
{
- char tbuf[MaxTupleSize];
+ struct {
+ HeapTupleHeaderData hdr;
+ char data[MaxTupleSize];
+ } tbuf;
+ HeapTupleHeader htup;
xl_heap_header xlhdr;
uint32 newlen;
@@ -2359,11 +2374,15 @@ heap_xlog_insert(bool redo, XLogRecPtr lsn, XLogRecord *record)
elog(STOP, "heap_insert_redo: invalid max offset number");
newlen = record->xl_len - SizeOfHeapInsert - SizeOfHeapHeader;
- memcpy((char *) &xlhdr, (char *) xlrec + SizeOfHeapInsert, SizeOfHeapHeader);
- memcpy(tbuf + offsetof(HeapTupleHeaderData, t_bits),
- (char *) xlrec + SizeOfHeapInsert + SizeOfHeapHeader, newlen);
+ Assert(newlen <= MaxTupleSize);
+ memcpy((char *) &xlhdr,
+ (char *) xlrec + SizeOfHeapInsert,
+ SizeOfHeapHeader);
+ memcpy((char *) &tbuf + offsetof(HeapTupleHeaderData, t_bits),
+ (char *) xlrec + SizeOfHeapInsert + SizeOfHeapHeader,
+ newlen);
newlen += offsetof(HeapTupleHeaderData, t_bits);
- htup = (HeapTupleHeader) tbuf;
+ htup = &tbuf.hdr;
htup->t_oid = xlhdr.t_oid;
htup->t_natts = xlhdr.t_natts;
htup->t_hoff = xlhdr.t_hoff;
@@ -2496,7 +2515,10 @@ newsame:;
if (redo)
{
- char tbuf[MaxTupleSize];
+ struct {
+ HeapTupleHeaderData hdr;
+ char data[MaxTupleSize];
+ } tbuf;
xl_heap_header xlhdr;
int hsize;
uint32 newlen;
@@ -2522,20 +2544,27 @@ newsame:;
hsize += (2 * sizeof(TransactionId));
newlen = record->xl_len - hsize;
- memcpy((char *) &xlhdr, (char *) xlrec + SizeOfHeapUpdate, SizeOfHeapHeader);
- memcpy(tbuf + offsetof(HeapTupleHeaderData, t_bits),
- (char *) xlrec + hsize, newlen);
+ Assert(newlen <= MaxTupleSize);
+ memcpy((char *) &xlhdr,
+ (char *) xlrec + SizeOfHeapUpdate,
+ SizeOfHeapHeader);
+ memcpy((char *) &tbuf + offsetof(HeapTupleHeaderData, t_bits),
+ (char *) xlrec + hsize,
+ newlen);
newlen += offsetof(HeapTupleHeaderData, t_bits);
- htup = (HeapTupleHeader) tbuf;
+ htup = &tbuf.hdr;
htup->t_oid = xlhdr.t_oid;
htup->t_natts = xlhdr.t_natts;
htup->t_hoff = xlhdr.t_hoff;
if (move)
{
hsize = SizeOfHeapUpdate + SizeOfHeapHeader;
- memcpy(&(htup->t_xmax), (char *) xlrec + hsize, sizeof(TransactionId));
+ memcpy(&(htup->t_xmax),
+ (char *) xlrec + hsize,
+ sizeof(TransactionId));
memcpy(&(htup->t_xmin),
- (char *) xlrec + hsize + sizeof(TransactionId), sizeof(TransactionId));
+ (char *) xlrec + hsize + sizeof(TransactionId),
+ sizeof(TransactionId));
TransactionIdStore(record->xl_xid, (TransactionId *) &(htup->t_cmin));
htup->t_infomask = xlhdr.mask;
htup->t_infomask &= ~(HEAP_XMIN_COMMITTED |
generated by cgit v1.2.3 (git 2.25.1) at 2025-06-14 10:21:11 +0000