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diff --git a/src/backend/access/common/heaptuple.c b/src/backend/access/common/heaptuple.c
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+/*-------------------------------------------------------------------------
+ *
+ * heaptuple.c--
+ * This file contains heap tuple accessor and mutator routines, as well
+ * as a few various tuple utilities.
+ *
+ * Copyright (c) 1994, Regents of the University of California
+ *
+ *
+ * IDENTIFICATION
+ * $Header: /cvsroot/pgsql/src/backend/access/common/heaptuple.c,v 1.1.1.1 1996/07/09 06:21:09 scrappy Exp $
+ *
+ * NOTES
+ * The old interface functions have been converted to macros
+ * and moved to heapam.h
+ *
+ *-------------------------------------------------------------------------
+ */
+#include <string.h>
+
+#include "postgres.h"
+
+#include "access/htup.h"
+#include "access/itup.h"
+#include "access/tupmacs.h"
+#include "access/skey.h"
+#include "storage/ipc.h"
+#include "storage/buf.h"
+#include "storage/bufmgr.h"
+#include "access/transam.h"
+#include "storage/bufpage.h" /* for MAXTUPLEN */
+#include "storage/itemptr.h"
+#include "utils/memutils.h"
+#include "utils/elog.h"
+#include "utils/palloc.h"
+#include "utils/rel.h"
+#include "utils/nabstime.h"
+
+/* this is so the sparcstation debugger works */
+
+#ifndef NO_ASSERT_CHECKING
+#ifdef sparc
+#define register
+#endif /* sparc */
+#endif /* NO_ASSERT_CHECKING */
+
+/* ----------------------------------------------------------------
+ * misc support routines
+ * ----------------------------------------------------------------
+ */
+
+/* ----------------
+ * ComputeDataSize
+ * ----------------
+ */
+Size
+ComputeDataSize(TupleDesc tupleDesc,
+ Datum value[],
+ char nulls[])
+{
+ uint32 length;
+ int i;
+ int numberOfAttributes = tupleDesc->natts;
+ AttributeTupleForm *att = tupleDesc->attrs;
+
+ for (length = 0, i = 0; i < numberOfAttributes; i++) {
+ if (nulls[i] != ' ') continue;
+
+ switch (att[i]->attlen) {
+ case -1:
+ /*
+ * This is the size of the disk representation and so
+ * must include the additional sizeof long.
+ */
+ if (att[i]->attalign == 'd') {
+ length = DOUBLEALIGN(length)
+ + VARSIZE(DatumGetPointer(value[i]));
+ } else {
+ length = INTALIGN(length)
+ + VARSIZE(DatumGetPointer(value[i]));
+ }
+ break;
+ case sizeof(char):
+ length++;
+ break;
+ case sizeof(short):
+ length = SHORTALIGN(length + sizeof(short));
+ break;
+ case sizeof(int32):
+ length = INTALIGN(length + sizeof(int32));
+ break;
+ default:
+ if (att[i]->attlen < sizeof(int32))
+ elog(WARN, "ComputeDataSize: attribute %d has len %d",
+ i, att[i]->attlen);
+ if (att[i]->attalign == 'd')
+ length = DOUBLEALIGN(length) + att[i]->attlen;
+ else
+ length = LONGALIGN(length) + att[i]->attlen;
+ break;
+ }
+ }
+
+ return length;
+}
+
+/* ----------------
+ * DataFill
+ * ----------------
+ */
+void
+DataFill(char *data,
+ TupleDesc tupleDesc,
+ Datum value[],
+ char nulls[],
+ char *infomask,
+ bits8 bit[])
+{
+ bits8 *bitP;
+ int bitmask;
+ uint32 length;
+ int i;
+ int numberOfAttributes = tupleDesc->natts;
+ AttributeTupleForm* att = tupleDesc->attrs;
+
+ if (bit != NULL) {
+ bitP = &bit[-1];
+ bitmask = CSIGNBIT;
+ }
+
+ *infomask = 0;
+
+ for (i = 0; i < numberOfAttributes; i++) {
+ if (bit != NULL) {
+ if (bitmask != CSIGNBIT) {
+ bitmask <<= 1;
+ } else {
+ bitP += 1;
+ *bitP = 0x0;
+ bitmask = 1;
+ }
+
+ if (nulls[i] == 'n') {
+ *infomask |= HEAP_HASNULL;
+ continue;
+ }
+
+ *bitP |= bitmask;
+ }
+
+ switch (att[i]->attlen) {
+ case -1:
+ *infomask |= HEAP_HASVARLENA;
+ if (att[i]->attalign=='d') {
+ data = (char *) DOUBLEALIGN(data);
+ } else {
+ data = (char *) INTALIGN(data);
+ }
+ length = VARSIZE(DatumGetPointer(value[i]));
+ memmove(data, DatumGetPointer(value[i]),length);
+ data += length;
+ break;
+ case sizeof(char):
+ *data = att[i]->attbyval ?
+ DatumGetChar(value[i]) : *((char *) value[i]);
+ data += sizeof(char);
+ break;
+ case sizeof(int16):
+ data = (char *) SHORTALIGN(data);
+ * (short *) data = (att[i]->attbyval ?
+ DatumGetInt16(value[i]) :
+ *((short *) value[i]));
+ data += sizeof(short);
+ break;
+ case sizeof(int32):
+ data = (char *) INTALIGN(data);
+ * (int32 *) data = (att[i]->attbyval ?
+ DatumGetInt32(value[i]) :
+ *((int32 *) value[i]));
+ data += sizeof(int32);
+ break;
+ default:
+ if (att[i]->attlen < sizeof(int32))
+ elog(WARN, "DataFill: attribute %d has len %d",
+ i, att[i]->attlen);
+ if (att[i]->attalign == 'd') {
+ data = (char *) DOUBLEALIGN(data);
+ memmove(data, DatumGetPointer(value[i]),
+ att[i]->attlen);
+ data += att[i]->attlen;
+ } else {
+ data = (char *) LONGALIGN(data);
+ memmove(data, DatumGetPointer(value[i]),
+ att[i]->attlen);
+ data += att[i]->attlen;
+ }
+
+ }
+ }
+}
+
+/* ----------------------------------------------------------------
+ * heap tuple interface
+ * ----------------------------------------------------------------
+ */
+
+/* ----------------
+ * heap_attisnull - returns 1 iff tuple attribute is not present
+ * ----------------
+ */
+int
+heap_attisnull(HeapTuple tup, int attnum)
+{
+ if (attnum > (int)tup->t_natts)
+ return (1);
+
+ if (HeapTupleNoNulls(tup)) return(0);
+
+ if (attnum > 0) {
+ return(att_isnull(attnum - 1, tup->t_bits));
+ } else
+ switch (attnum) {
+ case SelfItemPointerAttributeNumber:
+ case ObjectIdAttributeNumber:
+ case MinTransactionIdAttributeNumber:
+ case MinCommandIdAttributeNumber:
+ case MaxTransactionIdAttributeNumber:
+ case MaxCommandIdAttributeNumber:
+ case ChainItemPointerAttributeNumber:
+ case AnchorItemPointerAttributeNumber:
+ case MinAbsoluteTimeAttributeNumber:
+ case MaxAbsoluteTimeAttributeNumber:
+ case VersionTypeAttributeNumber:
+ break;
+
+ case 0:
+ elog(WARN, "heap_attisnull: zero attnum disallowed");
+
+ default:
+ elog(WARN, "heap_attisnull: undefined negative attnum");
+ }
+
+ return (0);
+}
+
+/* ----------------------------------------------------------------
+ * system attribute heap tuple support
+ * ----------------------------------------------------------------
+ */
+
+/* ----------------
+ * heap_sysattrlen
+ *
+ * This routine returns the length of a system attribute.
+ * ----------------
+ */
+int
+heap_sysattrlen(AttrNumber attno)
+{
+ HeapTupleData *f = NULL;
+ int len;
+
+ switch (attno) {
+ case SelfItemPointerAttributeNumber:
+ len = sizeof f->t_ctid;
+ break;
+ case ObjectIdAttributeNumber:
+ len = sizeof f->t_oid;
+ break;
+ case MinTransactionIdAttributeNumber:
+ len = sizeof f->t_xmin;
+ break;
+ case MinCommandIdAttributeNumber:
+ len = sizeof f->t_cmin;
+ break;
+ case MaxTransactionIdAttributeNumber:
+ len = sizeof f->t_xmax;
+ break;
+ case MaxCommandIdAttributeNumber:
+ len = sizeof f->t_cmax;
+ break;
+ case ChainItemPointerAttributeNumber:
+ len = sizeof f->t_chain;
+ break;
+ case AnchorItemPointerAttributeNumber:
+ elog(WARN, "heap_sysattrlen: field t_anchor does not exist!");
+ break;
+ case MinAbsoluteTimeAttributeNumber:
+ len = sizeof f->t_tmin;
+ break;
+ case MaxAbsoluteTimeAttributeNumber:
+ len = sizeof f->t_tmax;
+ break;
+ case VersionTypeAttributeNumber:
+ len = sizeof f->t_vtype;
+ break;
+ default:
+ elog(WARN, "sysattrlen: System attribute number %d unknown.",
+ attno);
+ len = 0;
+ break;
+ }
+ return (len);
+}
+
+/* ----------------
+ * heap_sysattrbyval
+ *
+ * This routine returns the "by-value" property of a system attribute.
+ * ----------------
+ */
+bool
+heap_sysattrbyval(AttrNumber attno)
+{
+ bool byval;
+
+ switch (attno) {
+ case SelfItemPointerAttributeNumber:
+ byval = false;
+ break;
+ case ObjectIdAttributeNumber:
+ byval = true;
+ break;
+ case MinTransactionIdAttributeNumber:
+ byval = true;
+ break;
+ case MinCommandIdAttributeNumber:
+ byval = true;
+ break;
+ case MaxTransactionIdAttributeNumber:
+ byval = true;
+ break;
+ case MaxCommandIdAttributeNumber:
+ byval = true;
+ break;
+ case ChainItemPointerAttributeNumber:
+ byval = false;
+ break;
+ case AnchorItemPointerAttributeNumber:
+ byval = false;
+ break;
+ case MinAbsoluteTimeAttributeNumber:
+ byval = true;
+ break;
+ case MaxAbsoluteTimeAttributeNumber:
+ byval = true;
+ break;
+ case VersionTypeAttributeNumber:
+ byval = true;
+ break;
+ default:
+ byval = true;
+ elog(WARN, "sysattrbyval: System attribute number %d unknown.",
+ attno);
+ break;
+ }
+
+ return byval;
+}
+
+/* ----------------
+ * heap_getsysattr
+ * ----------------
+ */
+char *
+heap_getsysattr(HeapTuple tup, Buffer b, int attnum)
+{
+ switch (attnum) {
+ case SelfItemPointerAttributeNumber:
+ return ((char *)&tup->t_ctid);
+ case ObjectIdAttributeNumber:
+ return ((char *) (long) tup->t_oid);
+ case MinTransactionIdAttributeNumber:
+ return ((char *) (long) tup->t_xmin);
+ case MinCommandIdAttributeNumber:
+ return ((char *) (long) tup->t_cmin);
+ case MaxTransactionIdAttributeNumber:
+ return ((char *) (long) tup->t_xmax);
+ case MaxCommandIdAttributeNumber:
+ return ((char *) (long) tup->t_cmax);
+ case ChainItemPointerAttributeNumber:
+ return ((char *) &tup->t_chain);
+ case AnchorItemPointerAttributeNumber:
+ elog(WARN, "heap_getsysattr: t_anchor does not exist!");
+ break;
+
+ /*
+ * For tmin and tmax, we need to do some extra work. These don't
+ * get filled in until the vacuum cleaner runs (or we manage to flush
+ * a page after setting the value correctly below). If the vacuum
+ * cleaner hasn't run yet, then the times stored in the tuple are
+ * wrong, and we need to look up the commit time of the transaction.
+ * We cache this value in the tuple to avoid doing the work more than
+ * once.
+ */
+
+ case MinAbsoluteTimeAttributeNumber:
+ if (!AbsoluteTimeIsBackwardCompatiblyValid(tup->t_tmin) &&
+ TransactionIdDidCommit(tup->t_xmin))
+ tup->t_tmin = TransactionIdGetCommitTime(tup->t_xmin);
+ return ((char *) (long) tup->t_tmin);
+ case MaxAbsoluteTimeAttributeNumber:
+ if (!AbsoluteTimeIsBackwardCompatiblyReal(tup->t_tmax)) {
+ if (TransactionIdDidCommit(tup->t_xmax))
+ tup->t_tmax = TransactionIdGetCommitTime(tup->t_xmax);
+ else
+ tup->t_tmax = CURRENT_ABSTIME;
+ }
+ return ((char *) (long) tup->t_tmax);
+ case VersionTypeAttributeNumber:
+ return ((char *) (long) tup->t_vtype);
+ default:
+ elog(WARN, "heap_getsysattr: undefined attnum %d", attnum);
+ }
+ return(NULL);
+}
+
+/* ----------------
+ * fastgetattr
+ *
+ * This is a newer version of fastgetattr which attempts to be
+ * faster by caching attribute offsets in the attribute descriptor.
+ *
+ * an alternate 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
+ * preform 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
+ * ----------------
+ */
+char *
+fastgetattr(HeapTuple tup,
+ int attnum,
+ TupleDesc tupleDesc,
+ bool *isnull)
+{
+ char *tp; /* ptr to att in tuple */
+ bits8 *bp; /* ptr to att in tuple */
+ int slow; /* do we have to walk nulls? */
+ AttributeTupleForm *att = tupleDesc->attrs;
+
+ /* ----------------
+ * sanity checks
+ * ----------------
+ */
+
+ Assert(PointerIsValid(isnull));
+ Assert(attnum > 0);
+
+ /* ----------------
+ * Three cases:
+ *
+ * 1: No nulls and no variable length attributes.
+ * 2: Has a null or a varlena AFTER att.
+ * 3: Has nulls or varlenas BEFORE att.
+ * ----------------
+ */
+
+ *isnull = false;
+
+ if (HeapTupleNoNulls(tup)) {
+ attnum--;
+ if (att[attnum]->attcacheoff > 0) {
+ return (char *)
+ fetchatt( &(att[attnum]),
+ (char *)tup + tup->t_hoff + att[attnum]->attcacheoff);
+ } else if (attnum == 0) {
+ /*
+ * first attribute is always at position zero
+ */
+ return((char *) fetchatt(&(att[0]), (char *) tup + tup->t_hoff));
+ }
+
+ tp = (char *) tup + tup->t_hoff;
+
+ slow = 0;
+ } else {
+ /*
+ * there's a null somewhere in the tuple
+ */
+
+ bp = tup->t_bits;
+ tp = (char *) tup + tup->t_hoff;
+ slow = 0;
+ attnum--;
+
+ /* ----------------
+ * check to see if desired att is null
+ * ----------------
+ */
+
+ if (att_isnull(attnum, bp)) {
+ *isnull = true;
+ return NULL;
+ }
+
+ /* ----------------
+ * Now check to see if any preceeding bits are null...
+ * ----------------
+ */
+
+ {
+ register int i = 0; /* current offset in bp */
+
+ for (i = 0; i < attnum && !slow; i++) {
+ if (att_isnull(i, bp)) slow = 1;
+ }
+ }
+ }
+
+ /*
+ * now check for any non-fixed length attrs before our attribute
+ */
+ if (!slow) {
+ if (att[attnum]->attcacheoff > 0) {
+ return (char *)
+ fetchatt(&(att[attnum]),
+ tp + att[attnum]->attcacheoff);
+ } else if (attnum == 0) {
+ return (char *)
+ fetchatt(&(att[0]), (char *) tup + tup->t_hoff);
+ } else if (!HeapTupleAllFixed(tup)) {
+ register int j = 0;
+
+ for (j = 0; j < attnum && !slow; j++)
+ if (att[j]->attlen < 1) slow = 1;
+ }
+ }
+
+ /*
+ * if slow is zero, and we got here, we know that we have a tuple with
+ * no nulls. We also have to initialize the remainder of
+ * the attribute cached offset values.
+ */
+ if (!slow) {
+ register int j = 1;
+ register long off;
+
+ /*
+ * need to set cache for some atts
+ */
+
+ att[0]->attcacheoff = 0;
+
+ while (att[j]->attcacheoff > 0) j++;
+
+ off = att[j-1]->attcacheoff + att[j-1]->attlen;
+
+ for (; j < attnum + 1; j++) {
+ switch(att[j]->attlen) {
+ case -1:
+ off = (att[j]->attalign=='d') ?
+ DOUBLEALIGN(off) : INTALIGN(off);
+ break;
+ case sizeof(char):
+ break;
+ case sizeof(short):
+ off = SHORTALIGN(off);
+ break;
+ case sizeof(int32):
+ off = INTALIGN(off);
+ break;
+ default:
+ if (att[j]->attlen < sizeof(int32)) {
+ elog(WARN,
+ "fastgetattr: attribute %d has len %d",
+ j, att[j]->attlen);
+ }
+ if (att[j]->attalign == 'd')
+ off = DOUBLEALIGN(off);
+ else
+ off = LONGALIGN(off);
+ break;
+ }
+
+ att[j]->attcacheoff = off;
+ off += att[j]->attlen;
+ }
+
+ return
+ (char *)fetchatt(&(att[attnum]), tp + att[attnum]->attcacheoff);
+ } else {
+ register bool usecache = true;
+ register int off = 0;
+ register int i;
+
+ /*
+ * Now we know that we have to walk the tuple CAREFULLY.
+ *
+ * Note - This loop is a little tricky. On iteration i we
+ * first set the offset for attribute i and figure out how much
+ * the offset should be incremented. Finally, we need to align the
+ * offset based on the size of attribute i+1 (for which the offset
+ * has been computed). -mer 12 Dec 1991
+ */
+
+ for (i = 0; i < attnum; i++) {
+ if (!HeapTupleNoNulls(tup)) {
+ if (att_isnull(i, bp)) {
+ usecache = false;
+ continue;
+ }
+ }
+ switch (att[i]->attlen) {
+ case -1:
+ off = (att[i]->attalign=='d') ?
+ DOUBLEALIGN(off) : INTALIGN(off);
+ break;
+ case sizeof(char):
+ break;
+ case sizeof(short):
+ off = SHORTALIGN(off);
+ break;
+ case sizeof(int32):
+ off = INTALIGN(off);
+ break;
+ default:
+ if (att[i]->attlen < sizeof(int32))
+ elog(WARN,
+ "fastgetattr2: attribute %d has len %d",
+ i, att[i]->attlen);
+ if (att[i]->attalign == 'd')
+ off = DOUBLEALIGN(off);
+ else
+ off = LONGALIGN(off);
+ break;
+ }
+ if (usecache && att[i]->attcacheoff > 0) {
+ off = att[i]->attcacheoff;
+ if (att[i]->attlen == -1) {
+ usecache = false;
+ }
+ } else {
+ if (usecache) att[i]->attcacheoff = off;
+ }
+
+ switch(att[i]->attlen) {
+ case sizeof(char):
+ off++;
+ break;
+ case sizeof(int16):
+ off += sizeof(int16);
+ break;
+ case sizeof(int32):
+ off += sizeof(int32);
+ break;
+ case -1:
+ usecache = false;
+ off += VARSIZE(tp + off);
+ break;
+ default:
+ off += att[i]->attlen;
+ break;
+ }
+ }
+ switch (att[attnum]->attlen) {
+ case -1:
+ off = (att[attnum]->attalign=='d')?
+ DOUBLEALIGN(off) : INTALIGN(off);
+ break;
+ case sizeof(char):
+ break;
+ case sizeof(short):
+ off = SHORTALIGN(off);
+ break;
+ case sizeof(int32):
+ off = INTALIGN(off);
+ break;
+ default:
+ if (att[attnum]->attlen < sizeof(int32))
+ elog(WARN, "fastgetattr3: attribute %d has len %d",
+ attnum, att[attnum]->attlen);
+ if (att[attnum]->attalign == 'd')
+ off = DOUBLEALIGN(off);
+ else
+ off = LONGALIGN(off);
+ break;
+ }
+ return((char *) fetchatt(&(att[attnum]), tp + off));
+ }
+}
+
+/* ----------------
+ * heap_getattr
+ *
+ * returns an attribute from a heap tuple. uses
+ * ----------------
+ */
+char *
+heap_getattr(HeapTuple tup,
+ Buffer b,
+ int attnum,
+ TupleDesc tupleDesc,
+ bool *isnull)
+{
+ bool localIsNull;
+
+ /* ----------------
+ * sanity checks
+ * ----------------
+ */
+ Assert(tup != NULL);
+
+ if (! PointerIsValid(isnull))
+ isnull = &localIsNull;
+
+ if (attnum > (int) tup->t_natts) {
+ *isnull = true;
+ return ((char *) NULL);
+ }
+
+ /* ----------------
+ * take care of user defined attributes
+ * ----------------
+ */
+ if (attnum > 0) {
+ char *datum;
+ datum = fastgetattr(tup, attnum, tupleDesc, isnull);
+
+ return (datum);
+ }
+
+ /* ----------------
+ * take care of system attributes
+ * ----------------
+ */
+ *isnull = false;
+ return
+ heap_getsysattr(tup, b, attnum);
+}
+
+/* ----------------
+ * heap_copytuple
+ *
+ * returns a copy of an entire tuple
+ * ----------------
+ */
+HeapTuple
+heap_copytuple(HeapTuple tuple)
+{
+ HeapTuple newTuple;
+
+ if (! HeapTupleIsValid(tuple))
+ return (NULL);
+
+ /* XXX For now, just prevent an undetectable executor related error */
+ if (tuple->t_len > MAXTUPLEN) {
+ elog(WARN, "palloctup: cannot handle length %d tuples",
+ tuple->t_len);
+ }
+
+ newTuple = (HeapTuple) palloc(tuple->t_len);
+ memmove((char *) newTuple, (char *) tuple, (int) tuple->t_len);
+ return(newTuple);
+}
+
+/* ----------------
+ * heap_deformtuple
+ *
+ * the inverse of heap_formtuple (see below)
+ * ----------------
+ */
+void
+heap_deformtuple(HeapTuple tuple,
+ TupleDesc tdesc,
+ Datum values[],
+ char nulls[])
+{
+ int i;
+ int natts;
+
+ Assert(HeapTupleIsValid(tuple));
+
+ natts = tuple->t_natts;
+ for (i = 0; i<natts; i++) {
+ bool isnull;
+
+ values[i] = (Datum)heap_getattr(tuple,
+ InvalidBuffer,
+ i+1,
+ tdesc,
+ &isnull);
+ if (isnull)
+ nulls[i] = 'n';
+ else
+ nulls[i] = ' ';
+ }
+}
+
+/* ----------------
+ * heap_formtuple
+ *
+ * constructs a tuple from the given value[] and null[] arrays
+ *
+ * old comments
+ * Handles alignment by aligning 2 byte attributes on short boundries
+ * and 3 or 4 byte attributes on long word boundries on a vax; and
+ * aligning non-byte attributes on short boundries on a sun. Does
+ * not properly align fixed length arrays of 1 or 2 byte types (yet).
+ *
+ * Null attributes are indicated by a 'n' in the appropriate byte
+ * of the null[]. Non-null attributes are indicated by a ' ' (space).
+ *
+ * Fix me. (Figure that must keep context if debug--allow give oid.)
+ * Assumes in order.
+ * ----------------
+ */
+HeapTuple
+heap_formtuple(TupleDesc tupleDescriptor,
+ Datum value[],
+ char nulls[])
+{
+ char *tp; /* tuple pointer */
+ HeapTuple tuple; /* return tuple */
+ int bitmaplen;
+ long len;
+ int hoff;
+ bool hasnull = false;
+ int i;
+ int numberOfAttributes = tupleDescriptor->natts;
+
+ len = sizeof *tuple - sizeof tuple->t_bits;
+
+ for (i = 0; i < numberOfAttributes && !hasnull; i++) {
+ if (nulls[i] != ' ') hasnull = true;
+ }
+
+ if (numberOfAttributes > MaxHeapAttributeNumber)
+ elog(WARN, "heap_formtuple: numberOfAttributes of %d > %d",
+ numberOfAttributes, MaxHeapAttributeNumber);
+
+ if (hasnull) {
+ bitmaplen = BITMAPLEN(numberOfAttributes);
+ len += bitmaplen;
+ }
+
+ hoff = len = DOUBLEALIGN(len); /* be conservative here */
+
+ len += ComputeDataSize(tupleDescriptor, value, nulls);
+
+ tp = (char *) palloc(len);
+ tuple = (HeapTuple) tp;
+
+ memset(tp, 0, (int)len);
+
+ tuple->t_len = len;
+ tuple->t_natts = numberOfAttributes;
+ tuple->t_hoff = hoff;
+ tuple->t_tmin = INVALID_ABSTIME;
+ tuple->t_tmax = CURRENT_ABSTIME;
+
+ DataFill((char *)tuple + tuple->t_hoff,
+ tupleDescriptor,
+ value,
+ nulls,
+ &tuple->t_infomask,
+ (hasnull ? tuple->t_bits : NULL));
+
+ return (tuple);
+}
+
+/* ----------------
+ * heap_modifytuple
+ *
+ * forms a new tuple from an old tuple and a set of replacement values.
+ * ----------------
+ */
+HeapTuple
+heap_modifytuple(HeapTuple tuple,
+ Buffer buffer,
+ Relation relation,
+ Datum replValue[],
+ char replNull[],
+ char repl[])
+{
+ int attoff;
+ int numberOfAttributes;
+ Datum *value;
+ char *nulls;
+ bool isNull;
+ HeapTuple newTuple;
+ int madecopy;
+ uint8 infomask;
+
+ /* ----------------
+ * sanity checks
+ * ----------------
+ */
+ Assert(HeapTupleIsValid(tuple));
+ Assert(BufferIsValid(buffer) || RelationIsValid(relation));
+ Assert(HeapTupleIsValid(tuple));
+ Assert(PointerIsValid(replValue));
+ Assert(PointerIsValid(replNull));
+ Assert(PointerIsValid(repl));
+
+ /* ----------------
+ * if we're pointing to a disk page, then first
+ * make a copy of our tuple so that all the attributes
+ * are available. XXX this is inefficient -cim
+ * ----------------
+ */
+ madecopy = 0;
+ if (BufferIsValid(buffer) == true) {
+ relation = (Relation) BufferGetRelation(buffer);
+ tuple = heap_copytuple(tuple);
+ madecopy = 1;
+ }
+
+ numberOfAttributes = RelationGetRelationTupleForm(relation)->relnatts;
+
+ /* ----------------
+ * allocate and fill value[] and nulls[] arrays from either
+ * the tuple or the repl information, as appropriate.
+ * ----------------
+ */
+ value = (Datum *) palloc(numberOfAttributes * sizeof *value);
+ nulls = (char *) palloc(numberOfAttributes * sizeof *nulls);
+
+ for (attoff = 0;
+ attoff < numberOfAttributes;
+ attoff += 1) {
+
+ if (repl[attoff] == ' ') {
+ char *attr;
+
+ attr =
+ heap_getattr(tuple,
+ InvalidBuffer,
+ AttrOffsetGetAttrNumber(attoff),
+ RelationGetTupleDescriptor(relation),
+ &isNull) ;
+ value[attoff] = PointerGetDatum(attr);
+ nulls[attoff] = (isNull) ? 'n' : ' ';
+
+ } else if (repl[attoff] != 'r') {
+ elog(WARN, "heap_modifytuple: repl is \\%3d", repl[attoff]);
+
+ } else { /* == 'r' */
+ value[attoff] = replValue[attoff];
+ nulls[attoff] = replNull[attoff];
+ }
+ }
+
+ /* ----------------
+ * create a new tuple from the values[] and nulls[] arrays
+ * ----------------
+ */
+ newTuple = heap_formtuple(RelationGetTupleDescriptor(relation),
+ value,
+ nulls);
+
+ /* ----------------
+ * copy the header except for t_len, t_natts, t_hoff, t_bits, t_infomask
+ * ----------------
+ */
+ infomask = newTuple->t_infomask;
+ memmove((char *) &newTuple->t_ctid, /*XXX*/
+ (char *) &tuple->t_ctid,
+ ((char *) &tuple->t_hoff - (char *) &tuple->t_ctid)); /*XXX*/
+ newTuple->t_infomask = infomask;
+ newTuple->t_natts = numberOfAttributes; /* fix t_natts just in case */
+
+ /* ----------------
+ * if we made a copy of the tuple, then free it.
+ * ----------------
+ */
+ if (madecopy)
+ pfree(tuple);
+
+ return
+ newTuple;
+}
+
+/* ----------------------------------------------------------------
+ * other misc functions
+ * ----------------------------------------------------------------
+ */
+
+HeapTuple
+heap_addheader(uint32 natts, /* max domain index */
+ int structlen, /* its length */
+ char *structure) /* pointer to the struct */
+{
+ register char *tp; /* tuple data pointer */
+ HeapTuple tup;
+ long len;
+ int hoff;
+
+ AssertArg(natts > 0);
+
+ len = sizeof (HeapTupleData) - sizeof (tup->t_bits);
+
+ hoff = len = DOUBLEALIGN(len); /* be conservative */
+ len += structlen;
+ tp = (char *) palloc(len);
+ tup = (HeapTuple) tp;
+ memset((char*)tup, 0, len);
+
+ tup->t_len = (short) len; /* XXX */
+ tp += tup->t_hoff = hoff;
+ tup->t_natts = natts;
+ tup->t_infomask = 0;
+
+ memmove(tp, structure, structlen);
+
+ return (tup);
+}
generated by cgit v1.2.3 (git 2.25.1) at 2025-05-20 05:05:07 +0000