Age Owner TLA Line data Source code
1 : /*-------------------------------------------------------------------------
2 : *
3 : * heaptuple.c
4 : * This file contains heap tuple accessor and mutator routines, as well
5 : * as various tuple utilities.
6 : *
7 : * Some notes about varlenas and this code:
8 : *
9 : * Before Postgres 8.3 varlenas always had a 4-byte length header, and
10 : * therefore always needed 4-byte alignment (at least). This wasted space
11 : * for short varlenas, for example CHAR(1) took 5 bytes and could need up to
12 : * 3 additional padding bytes for alignment.
13 : *
14 : * Now, a short varlena (up to 126 data bytes) is reduced to a 1-byte header
15 : * and we don't align it. To hide this from datatype-specific functions that
16 : * don't want to deal with it, such a datum is considered "toasted" and will
17 : * be expanded back to the normal 4-byte-header format by pg_detoast_datum.
18 : * (In performance-critical code paths we can use pg_detoast_datum_packed
19 : * and the appropriate access macros to avoid that overhead.) Note that this
20 : * conversion is performed directly in heap_form_tuple, without invoking
21 : * heaptoast.c.
22 : *
23 : * This change will break any code that assumes it needn't detoast values
24 : * that have been put into a tuple but never sent to disk. Hopefully there
25 : * are few such places.
26 : *
27 : * Varlenas still have alignment INT (or DOUBLE) in pg_type/pg_attribute, since
28 : * that's the normal requirement for the untoasted format. But we ignore that
29 : * for the 1-byte-header format. This means that the actual start position
30 : * of a varlena datum may vary depending on which format it has. To determine
31 : * what is stored, we have to require that alignment padding bytes be zero.
32 : * (Postgres actually has always zeroed them, but now it's required!) Since
33 : * the first byte of a 1-byte-header varlena can never be zero, we can examine
34 : * the first byte after the previous datum to tell if it's a pad byte or the
35 : * start of a 1-byte-header varlena.
36 : *
37 : * Note that while formerly we could rely on the first varlena column of a
38 : * system catalog to be at the offset suggested by the C struct for the
39 : * catalog, this is now risky: it's only safe if the preceding field is
40 : * word-aligned, so that there will never be any padding.
41 : *
42 : * We don't pack varlenas whose attstorage is PLAIN, since the data type
43 : * isn't expecting to have to detoast values. This is used in particular
44 : * by oidvector and int2vector, which are used in the system catalogs
45 : * and we'd like to still refer to them via C struct offsets.
46 : *
47 : *
48 : * Portions Copyright (c) 1996-2023, PostgreSQL Global Development Group
49 : * Portions Copyright (c) 1994, Regents of the University of California
50 : *
51 : *
52 : * IDENTIFICATION
53 : * src/backend/access/common/heaptuple.c
54 : *
55 : *-------------------------------------------------------------------------
56 : */
57 :
58 : #include "postgres.h"
59 :
60 : #include "access/heaptoast.h"
61 : #include "access/sysattr.h"
62 : #include "access/tupdesc_details.h"
63 : #include "executor/tuptable.h"
64 : #include "utils/expandeddatum.h"
65 :
66 :
67 : /* Does att's datatype allow packing into the 1-byte-header varlena format? */
68 : #define ATT_IS_PACKABLE(att) \
69 : ((att)->attlen == -1 && (att)->attstorage != TYPSTORAGE_PLAIN)
70 : /* Use this if it's already known varlena */
71 : #define VARLENA_ATT_IS_PACKABLE(att) \
72 : ((att)->attstorage != TYPSTORAGE_PLAIN)
73 :
74 :
75 : /* ----------------------------------------------------------------
76 : * misc support routines
77 : * ----------------------------------------------------------------
78 : */
79 :
80 : /*
81 : * Return the missing value of an attribute, or NULL if there isn't one.
82 : */
83 : Datum
1838 andrew 84 CBC 179 : getmissingattr(TupleDesc tupleDesc,
85 : int attnum, bool *isnull)
86 : {
87 : Form_pg_attribute att;
88 :
89 179 : Assert(attnum <= tupleDesc->natts);
90 179 : Assert(attnum > 0);
91 :
92 179 : att = TupleDescAttr(tupleDesc, attnum - 1);
93 :
94 179 : if (att->atthasmissing)
95 : {
96 : AttrMissing *attrmiss;
97 :
98 27 : Assert(tupleDesc->constr);
99 27 : Assert(tupleDesc->constr->missing);
100 :
101 27 : attrmiss = tupleDesc->constr->missing + (attnum - 1);
102 :
1747 akapila 103 27 : if (attrmiss->am_present)
104 : {
1838 andrew 105 27 : *isnull = false;
1747 akapila 106 27 : return attrmiss->am_value;
107 : }
108 : }
109 :
1838 andrew 110 152 : *isnull = true;
111 152 : return PointerGetDatum(NULL);
112 : }
113 :
114 : /*
115 : * heap_compute_data_size
116 : * Determine size of the data area of a tuple to be constructed
117 : */
118 : Size
6598 tgl 119 70819324 : heap_compute_data_size(TupleDesc tupleDesc,
120 : Datum *values,
121 : bool *isnull)
122 : {
123 70819324 : Size data_length = 0;
124 : int i;
125 70819324 : int numberOfAttributes = tupleDesc->natts;
126 :
127 312276122 : for (i = 0; i < numberOfAttributes; i++)
128 : {
129 : Datum val;
130 : Form_pg_attribute atti;
131 :
132 241456798 : if (isnull[i])
133 24643065 : continue;
134 :
5847 135 216813733 : val = values[i];
2058 andres 136 216813733 : atti = TupleDescAttr(tupleDesc, i);
137 :
2887 tgl 138 216813733 : if (ATT_IS_PACKABLE(atti) &&
5847 139 19379453 : VARATT_CAN_MAKE_SHORT(DatumGetPointer(val)))
140 : {
141 : /*
142 : * we're anticipating converting to a short varlena header, so
143 : * adjust length and don't count any alignment
144 : */
145 15097645 : data_length += VARATT_CONVERTED_SHORT_SIZE(DatumGetPointer(val));
146 : }
2887 147 201716088 : else if (atti->attlen == -1 &&
148 7225359 : VARATT_IS_EXTERNAL_EXPANDED(DatumGetPointer(val)))
149 : {
150 : /*
151 : * we want to flatten the expanded value so that the constructed
152 : * tuple doesn't depend on it
153 : */
154 1482 : data_length = att_align_nominal(data_length, atti->attalign);
155 1482 : data_length += EOH_get_flat_size(DatumGetEOHP(val));
156 : }
157 : else
158 : {
159 201714606 : data_length = att_align_datum(data_length, atti->attalign,
160 : atti->attlen, val);
161 201714606 : data_length = att_addlength_datum(data_length, atti->attlen,
162 : val);
163 : }
164 : }
165 :
6598 166 70819324 : return data_length;
167 : }
168 :
169 : /*
170 : * Per-attribute helper for heap_fill_tuple and other routines building tuples.
171 : *
172 : * Fill in either a data value or a bit in the null bitmask
173 : */
174 : static inline void
1838 andrew 175 227577892 : fill_val(Form_pg_attribute att,
176 : bits8 **bit,
177 : int *bitmask,
178 : char **dataP,
179 : uint16 *infomask,
180 : Datum datum,
181 : bool isnull)
182 : {
183 : Size data_length;
184 227577892 : char *data = *dataP;
185 :
186 : /*
187 : * If we're building a null bitmap, set the appropriate bit for the
188 : * current column value here.
189 : */
190 227577892 : if (bit != NULL)
191 : {
192 108747506 : if (*bitmask != HIGHBIT)
193 92048041 : *bitmask <<= 1;
194 : else
195 : {
196 16699465 : *bit += 1;
197 16699465 : **bit = 0x0;
198 16699465 : *bitmask = 1;
199 : }
200 :
201 108747506 : if (isnull)
202 : {
203 24204217 : *infomask |= HEAP_HASNULL;
204 24204217 : return;
205 : }
206 :
207 84543289 : **bit |= *bitmask;
208 : }
209 :
210 : /*
211 : * XXX we use the att_align macros on the pointer value itself, not on an
212 : * offset. This is a bit of a hack.
213 : */
214 203373675 : if (att->attbyval)
215 : {
216 : /* pass-by-value */
217 164249476 : data = (char *) att_align_nominal(data, att->attalign);
218 164249476 : store_att_byval(data, datum, att->attlen);
219 164249476 : data_length = att->attlen;
220 : }
221 39124199 : else if (att->attlen == -1)
222 : {
223 : /* varlena */
224 20972742 : Pointer val = DatumGetPointer(datum);
225 :
226 20972742 : *infomask |= HEAP_HASVARWIDTH;
227 20972742 : if (VARATT_IS_EXTERNAL(val))
228 : {
229 34482 : if (VARATT_IS_EXTERNAL_EXPANDED(val))
230 1482 : {
231 : /*
232 : * we want to flatten the expanded value so that the
233 : * constructed tuple doesn't depend on it
234 : */
235 1482 : ExpandedObjectHeader *eoh = DatumGetEOHP(datum);
236 :
237 1482 : data = (char *) att_align_nominal(data,
238 : att->attalign);
239 1482 : data_length = EOH_get_flat_size(eoh);
240 1482 : EOH_flatten_into(eoh, data, data_length);
241 : }
242 : else
243 : {
244 33000 : *infomask |= HEAP_HASEXTERNAL;
245 : /* no alignment, since it's short by definition */
246 33000 : data_length = VARSIZE_EXTERNAL(val);
247 33000 : memcpy(data, val, data_length);
248 : }
249 : }
250 20938260 : else if (VARATT_IS_SHORT(val))
251 : {
252 : /* no alignment for short varlenas */
253 2993134 : data_length = VARSIZE_SHORT(val);
254 2993134 : memcpy(data, val, data_length);
255 : }
256 17945126 : else if (VARLENA_ATT_IS_PACKABLE(att) &&
257 15026699 : VARATT_CAN_MAKE_SHORT(val))
258 : {
259 : /* convert to short varlena -- no alignment */
260 14632681 : data_length = VARATT_CONVERTED_SHORT_SIZE(val);
261 14632681 : SET_VARSIZE_SHORT(data, data_length);
262 14632681 : memcpy(data + 1, VARDATA(val), data_length - 1);
263 : }
264 : else
265 : {
266 : /* full 4-byte header varlena */
267 3312445 : data = (char *) att_align_nominal(data,
268 : att->attalign);
269 3312445 : data_length = VARSIZE(val);
270 3312445 : memcpy(data, val, data_length);
271 : }
272 : }
273 18151457 : else if (att->attlen == -2)
274 : {
275 : /* cstring ... never needs alignment */
276 3904998 : *infomask |= HEAP_HASVARWIDTH;
1131 tgl 277 3904998 : Assert(att->attalign == TYPALIGN_CHAR);
1838 andrew 278 3904998 : data_length = strlen(DatumGetCString(datum)) + 1;
279 3904998 : memcpy(data, DatumGetPointer(datum), data_length);
280 : }
281 : else
282 : {
283 : /* fixed-length pass-by-reference */
284 14246459 : data = (char *) att_align_nominal(data, att->attalign);
285 14246459 : Assert(att->attlen > 0);
286 14246459 : data_length = att->attlen;
287 14246459 : memcpy(data, DatumGetPointer(datum), data_length);
288 : }
289 :
290 203373675 : data += data_length;
291 203373675 : *dataP = data;
292 : }
293 :
294 : /*
295 : * heap_fill_tuple
296 : * Load data portion of a tuple from values/isnull arrays
297 : *
298 : * We also fill the null bitmap (if any) and set the infomask bits
299 : * that reflect the tuple's data contents.
300 : *
301 : * NOTE: it is now REQUIRED that the caller have pre-zeroed the data area.
302 : */
303 : void
6598 tgl 304 60754017 : heap_fill_tuple(TupleDesc tupleDesc,
305 : Datum *values, bool *isnull,
306 : char *data, Size data_size,
307 : uint16 *infomask, bits8 *bit)
308 : {
309 : bits8 *bitP;
310 : int bitmask;
311 : int i;
312 60754017 : int numberOfAttributes = tupleDesc->natts;
313 :
314 : #ifdef USE_ASSERT_CHECKING
5847 315 60754017 : char *start = data;
316 : #endif
317 :
6598 318 60754017 : if (bit != NULL)
319 : {
320 5867085 : bitP = &bit[-1];
6314 bruce 321 5867085 : bitmask = HIGHBIT;
322 : }
323 : else
324 : {
325 : /* just to keep compiler quiet */
6598 tgl 326 54886932 : bitP = NULL;
327 54886932 : bitmask = 0;
328 : }
329 :
5847 330 60754017 : *infomask &= ~(HEAP_HASNULL | HEAP_HASVARWIDTH | HEAP_HASEXTERNAL);
331 :
6598 332 288331909 : for (i = 0; i < numberOfAttributes; i++)
333 : {
1838 andrew 334 227577892 : Form_pg_attribute attr = TupleDescAttr(tupleDesc, i);
335 :
336 455155784 : fill_val(attr,
337 227577892 : bitP ? &bitP : NULL,
338 : &bitmask,
339 : &data,
340 : infomask,
341 227577892 : values ? values[i] : PointerGetDatum(NULL),
342 227577892 : isnull ? isnull[i] : true);
343 : }
344 :
5847 tgl 345 60754017 : Assert((data - start) == data_size);
6598 346 60754017 : }
347 :
348 :
349 : /* ----------------------------------------------------------------
350 : * heap tuple interface
351 : * ----------------------------------------------------------------
352 : */
353 :
354 : /* ----------------
355 : * heap_attisnull - returns true iff tuple attribute is not present
356 : * ----------------
357 : */
358 : bool
1838 andrew 359 9757712 : heap_attisnull(HeapTuple tup, int attnum, TupleDesc tupleDesc)
360 : {
361 : /*
362 : * We allow a NULL tupledesc for relations not expected to have missing
363 : * values, such as catalog relations and indexes.
364 : */
365 9757712 : Assert(!tupleDesc || attnum <= tupleDesc->natts);
5934 bruce 366 9757712 : if (attnum > (int) HeapTupleHeaderGetNatts(tup->t_data))
367 : {
1838 andrew 368 UBC 0 : if (tupleDesc && TupleDescAttr(tupleDesc, attnum - 1)->atthasmissing)
369 0 : return false;
370 : else
371 0 : return true;
372 : }
373 :
9345 bruce 374 CBC 9757712 : if (attnum > 0)
375 : {
6883 tgl 376 9757712 : if (HeapTupleNoNulls(tup))
6598 377 1523 : return false;
8899 vadim4o 378 9756189 : return att_isnull(attnum - 1, tup->t_data->t_bits);
379 : }
380 :
6883 tgl 381 UBC 0 : switch (attnum)
382 : {
383 0 : case TableOidAttributeNumber:
384 : case SelfItemPointerAttributeNumber:
385 : case MinTransactionIdAttributeNumber:
386 : case MinCommandIdAttributeNumber:
387 : case MaxTransactionIdAttributeNumber:
388 : case MaxCommandIdAttributeNumber:
389 : /* these are never null */
390 0 : break;
391 :
392 0 : default:
393 0 : elog(ERROR, "invalid attnum: %d", attnum);
394 : }
395 :
6598 396 0 : return false;
397 : }
398 :
399 : /* ----------------
400 : * nocachegetattr
401 : *
402 : * This only gets called from fastgetattr() macro, in cases where
403 : * we can't use a cacheoffset and the value is not null.
404 : *
405 : * This caches attribute offsets in the attribute descriptor.
406 : *
407 : * An alternative way to speed things up would be to cache offsets
408 : * with the tuple, but that seems more difficult unless you take
409 : * the storage hit of actually putting those offsets into the
410 : * tuple you send to disk. Yuck.
411 : *
412 : * This scheme will be slightly slower than that, but should
413 : * perform well for queries which hit large #'s of tuples. After
414 : * you cache the offsets once, examining all the other tuples using
415 : * the same attribute descriptor will go much quicker. -cim 5/4/91
416 : *
417 : * NOTE: if you need to change this code, see also heap_deform_tuple.
418 : * Also see nocache_index_getattr, which is the same code for index
419 : * tuples.
420 : * ----------------
421 : */
422 : Datum
202 pg 423 GNC 241652016 : nocachegetattr(HeapTuple tup,
424 : int attnum,
425 : TupleDesc tupleDesc)
426 : {
427 241652016 : HeapTupleHeader td = tup->t_data;
428 : char *tp; /* ptr to data part of tuple */
429 241652016 : bits8 *bp = td->t_bits; /* ptr to null bitmap in tuple */
5847 tgl 430 CBC 241652016 : bool slow = false; /* do we have to walk attrs? */
431 : int off; /* current offset within data */
432 :
433 : /* ----------------
434 : * Three cases:
435 : *
436 : * 1: No nulls and no variable-width attributes.
437 : * 2: Has a null or a var-width AFTER att.
438 : * 3: Has nulls or var-widths BEFORE att.
439 : * ----------------
440 : */
441 :
442 241652016 : attnum--;
443 :
202 pg 444 GNC 241652016 : if (!HeapTupleNoNulls(tup))
445 : {
446 : /*
447 : * there's a null somewhere in the tuple
448 : *
449 : * check to see if any preceding bits are null...
450 : */
4382 bruce 451 CBC 224977296 : int byte = attnum >> 3;
4837 rhaas 452 224977296 : int finalbit = attnum & 0x07;
453 :
454 : /* check for nulls "before" final bit of last byte */
455 224977296 : if ((~bp[byte]) & ((1 << finalbit) - 1))
456 4196347 : slow = true;
457 : else
458 : {
459 : /* check for nulls in any "earlier" bytes */
460 : int i;
461 :
462 282047835 : for (i = 0; i < byte; i++)
463 : {
464 61567654 : if (bp[i] != 0xFF)
465 : {
466 300768 : slow = true;
467 300768 : break;
468 : }
469 : }
470 : }
471 : }
472 :
202 pg 473 GNC 241652016 : tp = (char *) td + td->t_hoff;
474 :
9345 bruce 475 CBC 241652016 : if (!slow)
476 : {
477 : Form_pg_attribute att;
478 :
479 : /*
480 : * If we get here, there are no nulls up to and including the target
481 : * attribute. If we have a cached offset, we can use it.
482 : */
2058 andres 483 237154901 : att = TupleDescAttr(tupleDesc, attnum);
484 237154901 : if (att->attcacheoff >= 0)
485 216774022 : return fetchatt(att, tp + att->attcacheoff);
486 :
487 : /*
488 : * Otherwise, check for non-fixed-length attrs up to and including
489 : * target. If there aren't any, it's safe to cheaply initialize the
490 : * cached offsets for these attrs.
491 : */
202 pg 492 GNC 20380879 : if (HeapTupleHasVarWidth(tup))
493 : {
494 : int j;
495 :
8841 tgl 496 CBC 66148513 : for (j = 0; j <= attnum; j++)
497 : {
2058 andres 498 66117272 : if (TupleDescAttr(tupleDesc, j)->attlen <= 0)
499 : {
8165 tgl 500 20285699 : slow = true;
8841 501 20285699 : break;
502 : }
503 : }
504 : }
505 : }
506 :
9345 bruce 507 24877994 : if (!slow)
508 : {
5847 tgl 509 95180 : int natts = tupleDesc->natts;
9173 bruce 510 95180 : int j = 1;
511 :
512 : /*
513 : * If we get here, we have a tuple with no nulls or var-widths up to
514 : * and including the target attribute, so we can use the cached offset
515 : * ... only we don't have it yet, or we'd not have got here. Since
516 : * it's cheap to compute offsets for fixed-width columns, we take the
517 : * opportunity to initialize the cached offsets for *all* the leading
518 : * fixed-width columns, in hope of avoiding future visits to this
519 : * routine.
520 : */
2058 andres 521 95180 : TupleDescAttr(tupleDesc, 0)->attcacheoff = 0;
522 :
523 : /* we might have set some offsets in the slow path previously */
524 99650 : while (j < natts && TupleDescAttr(tupleDesc, j)->attcacheoff > 0)
9345 bruce 525 4470 : j++;
526 :
2058 andres 527 95180 : off = TupleDescAttr(tupleDesc, j - 1)->attcacheoff +
528 95180 : TupleDescAttr(tupleDesc, j - 1)->attlen;
529 :
5847 tgl 530 922394 : for (; j < natts; j++)
531 : {
2058 andres 532 874562 : Form_pg_attribute att = TupleDescAttr(tupleDesc, j);
533 :
534 874562 : if (att->attlen <= 0)
5847 tgl 535 47348 : break;
536 :
2058 andres 537 827214 : off = att_align_nominal(off, att->attalign);
538 :
539 827214 : att->attcacheoff = off;
540 :
541 827214 : off += att->attlen;
542 : }
543 :
5847 tgl 544 95180 : Assert(j > attnum);
545 :
2058 andres 546 95180 : off = TupleDescAttr(tupleDesc, attnum)->attcacheoff;
547 : }
548 : else
549 : {
9173 bruce 550 24782814 : bool usecache = true;
551 : int i;
552 :
553 : /*
554 : * Now we know that we have to walk the tuple CAREFULLY. But we still
555 : * might be able to cache some offsets for next time.
556 : *
557 : * Note - This loop is a little tricky. For each non-null attribute,
558 : * we have to first account for alignment padding before the attr,
559 : * then advance over the attr based on its length. Nulls have no
560 : * storage and no alignment padding either. We can use/set
561 : * attcacheoff until we reach either a null or a var-width attribute.
562 : */
5847 tgl 563 24782814 : off = 0;
5624 bruce 564 24782814 : for (i = 0;; i++) /* loop exit is at "break" */
9345 565 146607753 : {
2058 andres 566 171390567 : Form_pg_attribute att = TupleDescAttr(tupleDesc, i);
567 :
202 pg 568 GNC 171390567 : if (HeapTupleHasNulls(tup) && att_isnull(i, bp))
569 : {
7023 tgl 570 CBC 13841126 : usecache = false;
5624 bruce 571 13841126 : continue; /* this cannot be the target att */
572 : }
573 :
574 : /* If we know the next offset, we can skip the rest */
2058 andres 575 157549441 : if (usecache && att->attcacheoff >= 0)
576 107172849 : off = att->attcacheoff;
577 50376592 : else if (att->attlen == -1)
578 : {
579 : /*
580 : * We can only cache the offset for a varlena attribute if the
581 : * offset is already suitably aligned, so that there would be
582 : * no pad bytes in any case: then the offset will be valid for
583 : * either an aligned or unaligned value.
584 : */
5847 tgl 585 18127750 : if (usecache &&
2058 andres 586 1782133 : off == att_align_nominal(off, att->attalign))
587 36727 : att->attcacheoff = off;
588 : else
589 : {
590 16308890 : off = att_align_pointer(off, att->attalign, -1,
591 : tp + off);
5847 tgl 592 16308890 : usecache = false;
593 : }
594 : }
595 : else
596 : {
597 : /* not varlena, so safe to use att_align_nominal */
2058 andres 598 34030975 : off = att_align_nominal(off, att->attalign);
599 :
9345 bruce 600 34030975 : if (usecache)
2058 andres 601 361607 : att->attcacheoff = off;
602 : }
603 :
5847 tgl 604 157549441 : if (i == attnum)
605 24782814 : break;
606 :
2058 andres 607 132766627 : off = att_addlength_pointer(off, att->attlen, tp + off);
608 :
609 132766627 : if (usecache && att->attlen <= 0)
8980 bruce 610 21618758 : usecache = false;
611 : }
612 : }
613 :
2058 andres 614 24877994 : return fetchatt(TupleDescAttr(tupleDesc, attnum), tp + off);
615 : }
616 :
617 : /* ----------------
618 : * heap_getsysattr
619 : *
620 : * Fetch the value of a system attribute for a tuple.
621 : *
622 : * This is a support routine for the heap_getattr macro. The macro
623 : * has already determined that the attnum refers to a system attribute.
624 : * ----------------
625 : */
626 : Datum
6947 tgl 627 634 : heap_getsysattr(HeapTuple tup, int attnum, TupleDesc tupleDesc, bool *isnull)
628 : {
629 : Datum result;
630 :
8138 631 634 : Assert(tup);
632 :
633 : /* Currently, no sys attribute ever reads as NULL. */
4837 rhaas 634 634 : *isnull = false;
635 :
8138 tgl 636 634 : switch (attnum)
637 : {
638 2 : case SelfItemPointerAttributeNumber:
639 : /* pass-by-reference datatype */
640 2 : result = PointerGetDatum(&(tup->t_self));
641 2 : break;
642 522 : case MinTransactionIdAttributeNumber:
3395 rhaas 643 522 : result = TransactionIdGetDatum(HeapTupleHeaderGetRawXmin(tup->t_data));
8138 tgl 644 522 : break;
645 15 : case MaxTransactionIdAttributeNumber:
3728 alvherre 646 15 : result = TransactionIdGetDatum(HeapTupleHeaderGetRawXmax(tup->t_data));
8138 tgl 647 15 : break;
5903 648 93 : case MinCommandIdAttributeNumber:
649 : case MaxCommandIdAttributeNumber:
650 :
651 : /*
652 : * cmin and cmax are now both aliases for the same field, which
653 : * can in fact also be a combo command id. XXX perhaps we should
654 : * return the "real" cmin or cmax if possible, that is if we are
655 : * inside the originating transaction?
656 : */
657 93 : result = CommandIdGetDatum(HeapTupleHeaderGetRawCommandId(tup->t_data));
8138 658 93 : break;
659 2 : case TableOidAttributeNumber:
660 2 : result = ObjectIdGetDatum(tup->t_tableOid);
661 2 : break;
8138 tgl 662 UBC 0 : default:
7202 663 0 : elog(ERROR, "invalid attnum: %d", attnum);
664 : result = 0; /* keep compiler quiet */
665 : break;
666 : }
8138 tgl 667 CBC 634 : return result;
668 : }
669 :
670 : /* ----------------
671 : * heap_copytuple
672 : *
673 : * returns a copy of an entire tuple
674 : *
675 : * The HeapTuple struct, tuple header, and tuple data are all allocated
676 : * as a single palloc() block.
677 : * ----------------
678 : */
679 : HeapTuple
9770 scrappy 680 12439146 : heap_copytuple(HeapTuple tuple)
681 : {
682 : HeapTuple newTuple;
683 :
8899 vadim4o 684 12439146 : if (!HeapTupleIsValid(tuple) || tuple->t_data == NULL)
8986 bruce 685 UBC 0 : return NULL;
686 :
8899 vadim4o 687 CBC 12439146 : newTuple = (HeapTuple) palloc(HEAPTUPLESIZE + tuple->t_len);
688 12439146 : newTuple->t_len = tuple->t_len;
689 12439146 : newTuple->t_self = tuple->t_self;
8181 tgl 690 12439146 : newTuple->t_tableOid = tuple->t_tableOid;
8899 vadim4o 691 12439146 : newTuple->t_data = (HeapTupleHeader) ((char *) newTuple + HEAPTUPLESIZE);
8181 tgl 692 12439146 : memcpy((char *) newTuple->t_data, (char *) tuple->t_data, tuple->t_len);
8986 bruce 693 12439146 : return newTuple;
694 : }
695 :
696 : /* ----------------
697 : * heap_copytuple_with_tuple
698 : *
699 : * copy a tuple into a caller-supplied HeapTuple management struct
700 : *
701 : * Note that after calling this function, the "dest" HeapTuple will not be
702 : * allocated as a single palloc() block (unlike with heap_copytuple()).
703 : * ----------------
704 : */
705 : void
8899 vadim4o 706 UBC 0 : heap_copytuple_with_tuple(HeapTuple src, HeapTuple dest)
707 : {
708 0 : if (!HeapTupleIsValid(src) || src->t_data == NULL)
709 : {
710 0 : dest->t_data = NULL;
711 0 : return;
712 : }
713 :
714 0 : dest->t_len = src->t_len;
715 0 : dest->t_self = src->t_self;
8181 tgl 716 0 : dest->t_tableOid = src->t_tableOid;
8899 vadim4o 717 0 : dest->t_data = (HeapTupleHeader) palloc(src->t_len);
8181 tgl 718 0 : memcpy((char *) dest->t_data, (char *) src->t_data, src->t_len);
719 : }
720 :
721 : /*
722 : * Expand a tuple which has fewer attributes than required. For each attribute
723 : * not present in the sourceTuple, if there is a missing value that will be
724 : * used. Otherwise the attribute will be set to NULL.
725 : *
726 : * The source tuple must have fewer attributes than the required number.
727 : *
728 : * Only one of targetHeapTuple and targetMinimalTuple may be supplied. The
729 : * other argument must be NULL.
730 : */
731 : static void
1838 andrew 732 0 : expand_tuple(HeapTuple *targetHeapTuple,
733 : MinimalTuple *targetMinimalTuple,
734 : HeapTuple sourceTuple,
735 : TupleDesc tupleDesc)
736 : {
737 0 : AttrMissing *attrmiss = NULL;
738 : int attnum;
739 : int firstmissingnum;
740 0 : bool hasNulls = HeapTupleHasNulls(sourceTuple);
741 : HeapTupleHeader targetTHeader;
742 0 : HeapTupleHeader sourceTHeader = sourceTuple->t_data;
743 0 : int sourceNatts = HeapTupleHeaderGetNatts(sourceTHeader);
744 0 : int natts = tupleDesc->natts;
745 : int sourceNullLen;
746 : int targetNullLen;
747 0 : Size sourceDataLen = sourceTuple->t_len - sourceTHeader->t_hoff;
748 : Size targetDataLen;
749 : Size len;
750 : int hoff;
751 0 : bits8 *nullBits = NULL;
752 0 : int bitMask = 0;
753 : char *targetData;
754 : uint16 *infoMask;
755 :
756 0 : Assert((targetHeapTuple && !targetMinimalTuple)
757 : || (!targetHeapTuple && targetMinimalTuple));
758 :
759 0 : Assert(sourceNatts < natts);
760 :
761 0 : sourceNullLen = (hasNulls ? BITMAPLEN(sourceNatts) : 0);
762 :
763 0 : targetDataLen = sourceDataLen;
764 :
765 0 : if (tupleDesc->constr &&
766 0 : tupleDesc->constr->missing)
767 : {
768 : /*
769 : * If there are missing values we want to put them into the tuple.
770 : * Before that we have to compute the extra length for the values
771 : * array and the variable length data.
772 : */
773 0 : attrmiss = tupleDesc->constr->missing;
774 :
775 : /*
776 : * Find the first item in attrmiss for which we don't have a value in
777 : * the source. We can ignore all the missing entries before that.
778 : */
779 0 : for (firstmissingnum = sourceNatts;
780 0 : firstmissingnum < natts;
781 0 : firstmissingnum++)
782 : {
1747 akapila 783 0 : if (attrmiss[firstmissingnum].am_present)
1838 andrew 784 0 : break;
785 : else
1658 786 0 : hasNulls = true;
787 : }
788 :
789 : /*
790 : * Now walk the missing attributes. If there is a missing value make
791 : * space for it. Otherwise, it's going to be NULL.
792 : */
793 0 : for (attnum = firstmissingnum;
794 0 : attnum < natts;
795 0 : attnum++)
796 : {
797 0 : if (attrmiss[attnum].am_present)
798 : {
799 0 : Form_pg_attribute att = TupleDescAttr(tupleDesc, attnum);
800 :
801 0 : targetDataLen = att_align_datum(targetDataLen,
802 : att->attalign,
803 : att->attlen,
804 : attrmiss[attnum].am_value);
805 :
806 0 : targetDataLen = att_addlength_pointer(targetDataLen,
807 : att->attlen,
808 : attrmiss[attnum].am_value);
809 : }
810 : else
811 : {
812 : /* no missing value, so it must be null */
813 0 : hasNulls = true;
814 : }
815 : }
816 : } /* end if have missing values */
817 : else
818 : {
819 : /*
820 : * If there are no missing values at all then NULLS must be allowed,
821 : * since some of the attributes are known to be absent.
822 : */
1838 823 0 : hasNulls = true;
824 : }
825 :
826 0 : len = 0;
827 :
828 0 : if (hasNulls)
829 : {
830 0 : targetNullLen = BITMAPLEN(natts);
831 0 : len += targetNullLen;
832 : }
833 : else
834 0 : targetNullLen = 0;
835 :
836 : /*
837 : * Allocate and zero the space needed. Note that the tuple body and
838 : * HeapTupleData management structure are allocated in one chunk.
839 : */
840 0 : if (targetHeapTuple)
841 : {
842 0 : len += offsetof(HeapTupleHeaderData, t_bits);
843 0 : hoff = len = MAXALIGN(len); /* align user data safely */
844 0 : len += targetDataLen;
845 :
846 0 : *targetHeapTuple = (HeapTuple) palloc0(HEAPTUPLESIZE + len);
847 0 : (*targetHeapTuple)->t_data
848 0 : = targetTHeader
849 0 : = (HeapTupleHeader) ((char *) *targetHeapTuple + HEAPTUPLESIZE);
850 0 : (*targetHeapTuple)->t_len = len;
851 0 : (*targetHeapTuple)->t_tableOid = sourceTuple->t_tableOid;
1628 852 0 : (*targetHeapTuple)->t_self = sourceTuple->t_self;
853 :
1838 854 0 : targetTHeader->t_infomask = sourceTHeader->t_infomask;
855 0 : targetTHeader->t_hoff = hoff;
856 0 : HeapTupleHeaderSetNatts(targetTHeader, natts);
857 0 : HeapTupleHeaderSetDatumLength(targetTHeader, len);
858 0 : HeapTupleHeaderSetTypeId(targetTHeader, tupleDesc->tdtypeid);
859 0 : HeapTupleHeaderSetTypMod(targetTHeader, tupleDesc->tdtypmod);
860 : /* We also make sure that t_ctid is invalid unless explicitly set */
861 0 : ItemPointerSetInvalid(&(targetTHeader->t_ctid));
862 0 : if (targetNullLen > 0)
863 0 : nullBits = (bits8 *) ((char *) (*targetHeapTuple)->t_data
864 : + offsetof(HeapTupleHeaderData, t_bits));
865 0 : targetData = (char *) (*targetHeapTuple)->t_data + hoff;
866 0 : infoMask = &(targetTHeader->t_infomask);
867 : }
868 : else
869 : {
870 0 : len += SizeofMinimalTupleHeader;
871 0 : hoff = len = MAXALIGN(len); /* align user data safely */
872 0 : len += targetDataLen;
873 :
874 0 : *targetMinimalTuple = (MinimalTuple) palloc0(len);
875 0 : (*targetMinimalTuple)->t_len = len;
876 0 : (*targetMinimalTuple)->t_hoff = hoff + MINIMAL_TUPLE_OFFSET;
877 0 : (*targetMinimalTuple)->t_infomask = sourceTHeader->t_infomask;
878 : /* Same macro works for MinimalTuples */
879 0 : HeapTupleHeaderSetNatts(*targetMinimalTuple, natts);
880 0 : if (targetNullLen > 0)
881 0 : nullBits = (bits8 *) ((char *) *targetMinimalTuple
882 0 : + offsetof(MinimalTupleData, t_bits));
883 0 : targetData = (char *) *targetMinimalTuple + hoff;
884 0 : infoMask = &((*targetMinimalTuple)->t_infomask);
885 : }
886 :
887 0 : if (targetNullLen > 0)
888 : {
889 0 : if (sourceNullLen > 0)
890 : {
891 : /* if bitmap pre-existed copy in - all is set */
892 0 : memcpy(nullBits,
893 : ((char *) sourceTHeader)
894 : + offsetof(HeapTupleHeaderData, t_bits),
895 : sourceNullLen);
896 0 : nullBits += sourceNullLen - 1;
897 : }
898 : else
899 : {
900 0 : sourceNullLen = BITMAPLEN(sourceNatts);
901 : /* Set NOT NULL for all existing attributes */
902 0 : memset(nullBits, 0xff, sourceNullLen);
903 :
904 0 : nullBits += sourceNullLen - 1;
905 :
906 0 : if (sourceNatts & 0x07)
907 : {
908 : /* build the mask (inverted!) */
909 0 : bitMask = 0xff << (sourceNatts & 0x07);
910 : /* Voila */
911 0 : *nullBits = ~bitMask;
912 : }
913 : }
914 :
915 0 : bitMask = (1 << ((sourceNatts - 1) & 0x07));
916 : } /* End if have null bitmap */
917 :
918 0 : memcpy(targetData,
919 0 : ((char *) sourceTuple->t_data) + sourceTHeader->t_hoff,
920 : sourceDataLen);
921 :
922 0 : targetData += sourceDataLen;
923 :
924 : /* Now fill in the missing values */
925 0 : for (attnum = sourceNatts; attnum < natts; attnum++)
926 : {
927 :
928 0 : Form_pg_attribute attr = TupleDescAttr(tupleDesc, attnum);
929 :
1747 akapila 930 0 : if (attrmiss && attrmiss[attnum].am_present)
931 : {
1838 andrew 932 0 : fill_val(attr,
933 0 : nullBits ? &nullBits : NULL,
934 : &bitMask,
935 : &targetData,
936 : infoMask,
1747 akapila 937 0 : attrmiss[attnum].am_value,
938 : false);
939 : }
940 : else
941 : {
1838 andrew 942 0 : fill_val(attr,
943 : &nullBits,
944 : &bitMask,
945 : &targetData,
946 : infoMask,
947 : (Datum) 0,
948 : true);
949 : }
950 : } /* end loop over missing attributes */
951 0 : }
952 :
953 : /*
954 : * Fill in the missing values for a minimal HeapTuple
955 : */
956 : MinimalTuple
957 0 : minimal_expand_tuple(HeapTuple sourceTuple, TupleDesc tupleDesc)
958 : {
959 : MinimalTuple minimalTuple;
960 :
961 0 : expand_tuple(NULL, &minimalTuple, sourceTuple, tupleDesc);
962 0 : return minimalTuple;
963 : }
964 :
965 : /*
966 : * Fill in the missing values for an ordinary HeapTuple
967 : */
968 : HeapTuple
969 0 : heap_expand_tuple(HeapTuple sourceTuple, TupleDesc tupleDesc)
970 : {
971 : HeapTuple heapTuple;
972 :
973 0 : expand_tuple(&heapTuple, NULL, sourceTuple, tupleDesc);
974 0 : return heapTuple;
975 : }
976 :
977 : /* ----------------
978 : * heap_copy_tuple_as_datum
979 : *
980 : * copy a tuple as a composite-type Datum
981 : * ----------------
982 : */
983 : Datum
3265 tgl 984 CBC 39565 : heap_copy_tuple_as_datum(HeapTuple tuple, TupleDesc tupleDesc)
985 : {
986 : HeapTupleHeader td;
987 :
988 : /*
989 : * If the tuple contains any external TOAST pointers, we have to inline
990 : * those fields to meet the conventions for composite-type Datums.
991 : */
992 39565 : if (HeapTupleHasExternal(tuple))
3265 tgl 993 UBC 0 : return toast_flatten_tuple_to_datum(tuple->t_data,
994 : tuple->t_len,
995 : tupleDesc);
996 :
997 : /*
998 : * Fast path for easy case: just make a palloc'd copy and insert the
999 : * correct composite-Datum header fields (since those may not be set if
1000 : * the given tuple came from disk, rather than from heap_form_tuple).
1001 : */
3265 tgl 1002 CBC 39565 : td = (HeapTupleHeader) palloc(tuple->t_len);
1003 39565 : memcpy((char *) td, (char *) tuple->t_data, tuple->t_len);
1004 :
1005 39565 : HeapTupleHeaderSetDatumLength(td, tuple->t_len);
1006 39565 : HeapTupleHeaderSetTypeId(td, tupleDesc->tdtypeid);
1007 39565 : HeapTupleHeaderSetTypMod(td, tupleDesc->tdtypmod);
1008 :
1009 39565 : return PointerGetDatum(td);
1010 : }
1011 :
1012 : /*
1013 : * heap_form_tuple
1014 : * construct a tuple from the given values[] and isnull[] arrays,
1015 : * which are of the length indicated by tupleDescriptor->natts
1016 : *
1017 : * The result is allocated in the current memory context.
1018 : */
1019 : HeapTuple
6598 1020 17219545 : heap_form_tuple(TupleDesc tupleDescriptor,
1021 : Datum *values,
1022 : bool *isnull)
1023 : {
1024 : HeapTuple tuple; /* return tuple */
1025 : HeapTupleHeader td; /* tuple data */
1026 : Size len,
1027 : data_len;
1028 : int hoff;
1029 17219545 : bool hasnull = false;
1030 17219545 : int numberOfAttributes = tupleDescriptor->natts;
1031 : int i;
1032 :
1033 17219545 : if (numberOfAttributes > MaxTupleAttributeNumber)
6598 tgl 1034 UBC 0 : ereport(ERROR,
1035 : (errcode(ERRCODE_TOO_MANY_COLUMNS),
1036 : errmsg("number of columns (%d) exceeds limit (%d)",
1037 : numberOfAttributes, MaxTupleAttributeNumber)));
1038 :
1039 : /*
1040 : * Check for nulls
1041 : */
6598 tgl 1042 CBC 133295076 : for (i = 0; i < numberOfAttributes; i++)
1043 : {
1044 121657992 : if (isnull[i])
1045 : {
3265 1046 5582461 : hasnull = true;
1047 5582461 : break;
1048 : }
1049 : }
1050 :
1051 : /*
1052 : * Determine total space needed
1053 : */
6598 1054 17219545 : len = offsetof(HeapTupleHeaderData, t_bits);
1055 :
1056 17219545 : if (hasnull)
1057 5582461 : len += BITMAPLEN(numberOfAttributes);
1058 :
1059 17219545 : hoff = len = MAXALIGN(len); /* align user data safely */
1060 :
5847 1061 17219545 : data_len = heap_compute_data_size(tupleDescriptor, values, isnull);
1062 :
1063 17219545 : len += data_len;
1064 :
1065 : /*
1066 : * Allocate and zero the space needed. Note that the tuple body and
1067 : * HeapTupleData management structure are allocated in one chunk.
1068 : */
2160 alvherre 1069 17219545 : tuple = (HeapTuple) palloc0(HEAPTUPLESIZE + len);
6598 tgl 1070 17219545 : tuple->t_data = td = (HeapTupleHeader) ((char *) tuple + HEAPTUPLESIZE);
1071 :
1072 : /*
1073 : * And fill in the information. Note we fill the Datum fields even though
1074 : * this tuple may never become a Datum. This lets HeapTupleHeaderGetDatum
1075 : * identify the tuple type if needed.
1076 : */
1077 17219545 : tuple->t_len = len;
1078 17219545 : ItemPointerSetInvalid(&(tuple->t_self));
1079 17219545 : tuple->t_tableOid = InvalidOid;
1080 :
1081 17219545 : HeapTupleHeaderSetDatumLength(td, len);
1082 17219545 : HeapTupleHeaderSetTypeId(td, tupleDescriptor->tdtypeid);
1083 17219545 : HeapTupleHeaderSetTypMod(td, tupleDescriptor->tdtypmod);
1084 : /* We also make sure that t_ctid is invalid unless explicitly set */
2888 1085 17219545 : ItemPointerSetInvalid(&(td->t_ctid));
1086 :
5934 bruce 1087 17219545 : HeapTupleHeaderSetNatts(td, numberOfAttributes);
6598 tgl 1088 17219545 : td->t_hoff = hoff;
1089 :
1090 17219545 : heap_fill_tuple(tupleDescriptor,
1091 : values,
1092 : isnull,
1093 : (char *) td + hoff,
1094 : data_len,
1095 : &td->t_infomask,
1096 : (hasnull ? td->t_bits : NULL));
1097 :
1098 17219545 : return tuple;
1099 : }
1100 :
1101 : /*
1102 : * heap_modify_tuple
1103 : * form a new tuple from an old tuple and a set of replacement values.
1104 : *
1105 : * The replValues, replIsnull, and doReplace arrays must be of the length
1106 : * indicated by tupleDesc->natts. The new tuple is constructed using the data
1107 : * from replValues/replIsnull at columns where doReplace is true, and using
1108 : * the data from the old tuple at columns where doReplace is false.
1109 : *
1110 : * The result is allocated in the current memory context.
1111 : */
1112 : HeapTuple
1113 100799 : heap_modify_tuple(HeapTuple tuple,
1114 : TupleDesc tupleDesc,
1115 : Datum *replValues,
1116 : bool *replIsnull,
1117 : bool *doReplace)
1118 : {
1119 100799 : int numberOfAttributes = tupleDesc->natts;
1120 : int attoff;
1121 : Datum *values;
1122 : bool *isnull;
1123 : HeapTuple newTuple;
1124 :
1125 : /*
1126 : * allocate and fill values and isnull arrays from either the tuple or the
1127 : * repl information, as appropriate.
1128 : *
1129 : * NOTE: it's debatable whether to use heap_deform_tuple() here or just
1130 : * heap_getattr() only the non-replaced columns. The latter could win if
1131 : * there are many replaced columns and few non-replaced ones. However,
1132 : * heap_deform_tuple costs only O(N) while the heap_getattr way would cost
1133 : * O(N^2) if there are many non-replaced columns, so it seems better to
1134 : * err on the side of linear cost.
1135 : */
1136 100799 : values = (Datum *) palloc(numberOfAttributes * sizeof(Datum));
1137 100799 : isnull = (bool *) palloc(numberOfAttributes * sizeof(bool));
1138 :
1139 100799 : heap_deform_tuple(tuple, tupleDesc, values, isnull);
1140 :
1141 3096479 : for (attoff = 0; attoff < numberOfAttributes; attoff++)
1142 : {
1143 2995680 : if (doReplace[attoff])
1144 : {
1145 1097547 : values[attoff] = replValues[attoff];
1146 1097547 : isnull[attoff] = replIsnull[attoff];
1147 : }
1148 : }
1149 :
1150 : /*
1151 : * create a new tuple from the values and isnull arrays
1152 : */
1153 100799 : newTuple = heap_form_tuple(tupleDesc, values, isnull);
1154 :
1155 100799 : pfree(values);
1156 100799 : pfree(isnull);
1157 :
1158 : /*
1159 : * copy the identification info of the old tuple: t_ctid, t_self
1160 : */
1161 100799 : newTuple->t_data->t_ctid = tuple->t_data->t_ctid;
1162 100799 : newTuple->t_self = tuple->t_self;
1163 100799 : newTuple->t_tableOid = tuple->t_tableOid;
1164 :
1165 100799 : return newTuple;
1166 : }
1167 :
1168 : /*
1169 : * heap_modify_tuple_by_cols
1170 : * form a new tuple from an old tuple and a set of replacement values.
1171 : *
1172 : * This is like heap_modify_tuple, except that instead of specifying which
1173 : * column(s) to replace by a boolean map, an array of target column numbers
1174 : * is used. This is often more convenient when a fixed number of columns
1175 : * are to be replaced. The replCols, replValues, and replIsnull arrays must
1176 : * be of length nCols. Target column numbers are indexed from 1.
1177 : *
1178 : * The result is allocated in the current memory context.
1179 : */
1180 : HeapTuple
2343 1181 18 : heap_modify_tuple_by_cols(HeapTuple tuple,
1182 : TupleDesc tupleDesc,
1183 : int nCols,
1184 : int *replCols,
1185 : Datum *replValues,
1186 : bool *replIsnull)
1187 : {
1188 18 : int numberOfAttributes = tupleDesc->natts;
1189 : Datum *values;
1190 : bool *isnull;
1191 : HeapTuple newTuple;
1192 : int i;
1193 :
1194 : /*
1195 : * allocate and fill values and isnull arrays from the tuple, then replace
1196 : * selected columns from the input arrays.
1197 : */
1198 18 : values = (Datum *) palloc(numberOfAttributes * sizeof(Datum));
1199 18 : isnull = (bool *) palloc(numberOfAttributes * sizeof(bool));
1200 :
1201 18 : heap_deform_tuple(tuple, tupleDesc, values, isnull);
1202 :
1203 36 : for (i = 0; i < nCols; i++)
1204 : {
1205 18 : int attnum = replCols[i];
1206 :
1207 18 : if (attnum <= 0 || attnum > numberOfAttributes)
2343 tgl 1208 UBC 0 : elog(ERROR, "invalid column number %d", attnum);
2343 tgl 1209 CBC 18 : values[attnum - 1] = replValues[i];
1210 18 : isnull[attnum - 1] = replIsnull[i];
1211 : }
1212 :
1213 : /*
1214 : * create a new tuple from the values and isnull arrays
1215 : */
1216 18 : newTuple = heap_form_tuple(tupleDesc, values, isnull);
1217 :
1218 18 : pfree(values);
1219 18 : pfree(isnull);
1220 :
1221 : /*
1222 : * copy the identification info of the old tuple: t_ctid, t_self
1223 : */
1224 18 : newTuple->t_data->t_ctid = tuple->t_data->t_ctid;
1225 18 : newTuple->t_self = tuple->t_self;
1226 18 : newTuple->t_tableOid = tuple->t_tableOid;
1227 :
1228 18 : return newTuple;
1229 : }
1230 :
1231 : /*
1232 : * heap_deform_tuple
1233 : * Given a tuple, extract data into values/isnull arrays; this is
1234 : * the inverse of heap_form_tuple.
1235 : *
1236 : * Storage for the values/isnull arrays is provided by the caller;
1237 : * it should be sized according to tupleDesc->natts not
1238 : * HeapTupleHeaderGetNatts(tuple->t_data).
1239 : *
1240 : * Note that for pass-by-reference datatypes, the pointer placed
1241 : * in the Datum will point into the given tuple.
1242 : *
1243 : * When all or most of a tuple's fields need to be extracted,
1244 : * this routine will be significantly quicker than a loop around
1245 : * heap_getattr; the loop will become O(N^2) as soon as any
1246 : * noncacheable attribute offsets are involved.
1247 : */
1248 : void
6598 1249 2944578 : heap_deform_tuple(HeapTuple tuple, TupleDesc tupleDesc,
1250 : Datum *values, bool *isnull)
1251 : {
1252 2944578 : HeapTupleHeader tup = tuple->t_data;
1253 2944578 : bool hasnulls = HeapTupleHasNulls(tuple);
1254 2944578 : int tdesc_natts = tupleDesc->natts;
1255 : int natts; /* number of atts to extract */
1256 : int attnum;
1257 : char *tp; /* ptr to tuple data */
1258 : uint32 off; /* offset in tuple data */
2118 1259 2944578 : bits8 *bp = tup->t_bits; /* ptr to null bitmap in tuple */
6598 1260 2944578 : bool slow = false; /* can we use/set attcacheoff? */
1261 :
5934 bruce 1262 2944578 : natts = HeapTupleHeaderGetNatts(tup);
1263 :
1264 : /*
1265 : * In inheritance situations, it is possible that the given tuple actually
1266 : * has more fields than the caller is expecting. Don't run off the end of
1267 : * the caller's arrays.
1268 : */
6598 tgl 1269 2944578 : natts = Min(natts, tdesc_natts);
1270 :
1271 2944578 : tp = (char *) tup + tup->t_hoff;
1272 :
1273 2944578 : off = 0;
1274 :
1275 13044109 : for (attnum = 0; attnum < natts; attnum++)
1276 : {
2058 andres 1277 10099531 : Form_pg_attribute thisatt = TupleDescAttr(tupleDesc, attnum);
1278 :
6598 tgl 1279 10099531 : if (hasnulls && att_isnull(attnum, bp))
1280 : {
1281 904245 : values[attnum] = (Datum) 0;
1282 904245 : isnull[attnum] = true;
1283 904245 : slow = true; /* can't use attcacheoff anymore */
1284 904245 : continue;
1285 : }
1286 :
1287 9195286 : isnull[attnum] = false;
1288 :
1289 9195286 : if (!slow && thisatt->attcacheoff >= 0)
1290 8543593 : off = thisatt->attcacheoff;
5847 1291 651693 : else if (thisatt->attlen == -1)
1292 : {
1293 : /*
1294 : * We can only cache the offset for a varlena attribute if the
1295 : * offset is already suitably aligned, so that there would be no
1296 : * pad bytes in any case: then the offset will be valid for either
1297 : * an aligned or unaligned value.
1298 : */
1299 434426 : if (!slow &&
1300 73159 : off == att_align_nominal(off, thisatt->attalign))
1301 23506 : thisatt->attcacheoff = off;
1302 : else
1303 : {
1304 337761 : off = att_align_pointer(off, thisatt->attalign, -1,
1305 : tp + off);
1306 337761 : slow = true;
1307 : }
1308 : }
1309 : else
1310 : {
1311 : /* not varlena, so safe to use att_align_nominal */
1312 290426 : off = att_align_nominal(off, thisatt->attalign);
1313 :
6598 1314 290426 : if (!slow)
1315 50667 : thisatt->attcacheoff = off;
1316 : }
1317 :
1318 9195286 : values[attnum] = fetchatt(thisatt, tp + off);
1319 :
5847 1320 9195286 : off = att_addlength_pointer(off, thisatt->attlen, tp + off);
1321 :
6598 1322 9195286 : if (thisatt->attlen <= 0)
1323 1527669 : slow = true; /* can't use attcacheoff anymore */
1324 : }
1325 :
1326 : /*
1327 : * If tuple doesn't have all the atts indicated by tupleDesc, read the
1328 : * rest as nulls or missing values as appropriate.
1329 : */
1330 2944591 : for (; attnum < tdesc_natts; attnum++)
1838 andrew 1331 13 : values[attnum] = getmissingattr(tupleDesc, attnum + 1, &isnull[attnum]);
6598 tgl 1332 2944578 : }
1333 :
1334 : /*
1335 : * heap_freetuple
1336 : */
1337 : void
8515 JanWieck 1338 15989368 : heap_freetuple(HeapTuple htup)
1339 : {
1340 15989368 : pfree(htup);
1341 15989368 : }
1342 :
1343 :
1344 : /*
1345 : * heap_form_minimal_tuple
1346 : * construct a MinimalTuple from the given values[] and isnull[] arrays,
1347 : * which are of the length indicated by tupleDescriptor->natts
1348 : *
1349 : * This is exactly like heap_form_tuple() except that the result is a
1350 : * "minimal" tuple lacking a HeapTupleData header as well as room for system
1351 : * columns.
1352 : *
1353 : * The result is allocated in the current memory context.
1354 : */
1355 : MinimalTuple
6130 tgl 1356 21034127 : heap_form_minimal_tuple(TupleDesc tupleDescriptor,
1357 : Datum *values,
1358 : bool *isnull)
1359 : {
1360 : MinimalTuple tuple; /* return tuple */
1361 : Size len,
1362 : data_len;
1363 : int hoff;
1364 21034127 : bool hasnull = false;
1365 21034127 : int numberOfAttributes = tupleDescriptor->natts;
1366 : int i;
1367 :
1368 21034127 : if (numberOfAttributes > MaxTupleAttributeNumber)
6130 tgl 1369 UBC 0 : ereport(ERROR,
1370 : (errcode(ERRCODE_TOO_MANY_COLUMNS),
1371 : errmsg("number of columns (%d) exceeds limit (%d)",
1372 : numberOfAttributes, MaxTupleAttributeNumber)));
1373 :
1374 : /*
1375 : * Check for nulls
1376 : */
6130 tgl 1377 CBC 58327922 : for (i = 0; i < numberOfAttributes; i++)
1378 : {
1379 37544234 : if (isnull[i])
1380 : {
3265 1381 250439 : hasnull = true;
1382 250439 : break;
1383 : }
1384 : }
1385 :
1386 : /*
1387 : * Determine total space needed
1388 : */
2969 1389 21034127 : len = SizeofMinimalTupleHeader;
1390 :
6130 1391 21034127 : if (hasnull)
1392 250439 : len += BITMAPLEN(numberOfAttributes);
1393 :
1394 21034127 : hoff = len = MAXALIGN(len); /* align user data safely */
1395 :
5847 1396 21034127 : data_len = heap_compute_data_size(tupleDescriptor, values, isnull);
1397 :
1398 21034127 : len += data_len;
1399 :
1400 : /*
1401 : * Allocate and zero the space needed.
1402 : */
6130 1403 21034127 : tuple = (MinimalTuple) palloc0(len);
1404 :
1405 : /*
1406 : * And fill in the information.
1407 : */
1408 21034127 : tuple->t_len = len;
5934 bruce 1409 21034127 : HeapTupleHeaderSetNatts(tuple, numberOfAttributes);
6130 tgl 1410 21034127 : tuple->t_hoff = hoff + MINIMAL_TUPLE_OFFSET;
1411 :
1412 21034127 : heap_fill_tuple(tupleDescriptor,
1413 : values,
1414 : isnull,
1415 : (char *) tuple + hoff,
1416 : data_len,
1417 : &tuple->t_infomask,
1418 : (hasnull ? tuple->t_bits : NULL));
1419 :
1420 21034127 : return tuple;
1421 : }
1422 :
1423 : /*
1424 : * heap_free_minimal_tuple
1425 : */
1426 : void
1427 19455939 : heap_free_minimal_tuple(MinimalTuple mtup)
1428 : {
1429 19455939 : pfree(mtup);
1430 19455939 : }
1431 :
1432 : /*
1433 : * heap_copy_minimal_tuple
1434 : * copy a MinimalTuple
1435 : *
1436 : * The result is allocated in the current memory context.
1437 : */
1438 : MinimalTuple
1439 2220124 : heap_copy_minimal_tuple(MinimalTuple mtup)
1440 : {
1441 : MinimalTuple result;
1442 :
1443 2220124 : result = (MinimalTuple) palloc(mtup->t_len);
1444 2220124 : memcpy(result, mtup, mtup->t_len);
1445 2220124 : return result;
1446 : }
1447 :
1448 : /*
1449 : * heap_tuple_from_minimal_tuple
1450 : * create a HeapTuple by copying from a MinimalTuple;
1451 : * system columns are filled with zeroes
1452 : *
1453 : * The result is allocated in the current memory context.
1454 : * The HeapTuple struct, tuple header, and tuple data are all allocated
1455 : * as a single palloc() block.
1456 : */
1457 : HeapTuple
1458 495681 : heap_tuple_from_minimal_tuple(MinimalTuple mtup)
1459 : {
1460 : HeapTuple result;
1461 495681 : uint32 len = mtup->t_len + MINIMAL_TUPLE_OFFSET;
1462 :
1463 495681 : result = (HeapTuple) palloc(HEAPTUPLESIZE + len);
1464 495681 : result->t_len = len;
1465 495681 : ItemPointerSetInvalid(&(result->t_self));
1466 495681 : result->t_tableOid = InvalidOid;
1467 495681 : result->t_data = (HeapTupleHeader) ((char *) result + HEAPTUPLESIZE);
1468 495681 : memcpy((char *) result->t_data + MINIMAL_TUPLE_OFFSET, mtup, mtup->t_len);
5934 bruce 1469 495681 : memset(result->t_data, 0, offsetof(HeapTupleHeaderData, t_infomask2));
6130 tgl 1470 495681 : return result;
1471 : }
1472 :
1473 : /*
1474 : * minimal_tuple_from_heap_tuple
1475 : * create a MinimalTuple by copying from a HeapTuple
1476 : *
1477 : * The result is allocated in the current memory context.
1478 : */
1479 : MinimalTuple
1480 1731880 : minimal_tuple_from_heap_tuple(HeapTuple htup)
1481 : {
1482 : MinimalTuple result;
1483 : uint32 len;
1484 :
1485 1731880 : Assert(htup->t_len > MINIMAL_TUPLE_OFFSET);
1486 1731880 : len = htup->t_len - MINIMAL_TUPLE_OFFSET;
1487 1731880 : result = (MinimalTuple) palloc(len);
1488 1731880 : memcpy(result, (char *) htup->t_data + MINIMAL_TUPLE_OFFSET, len);
1489 1731880 : result->t_len = len;
1490 1731880 : return result;
1491 : }
1492 :
1493 : /*
1494 : * This mainly exists so JIT can inline the definition, but it's also
1495 : * sometimes useful in debugging sessions.
1496 : */
1497 : size_t
1840 andres 1498 162030 : varsize_any(void *p)
1499 : {
1500 162030 : return VARSIZE_ANY(p);
1501 : }
|
