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proto.c
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1 /*-------------------------------------------------------------------------
2  *
3  * proto.c
4  * logical replication protocol functions
5  *
6  * Copyright (c) 2015-2022, PostgreSQL Global Development Group
7  *
8  * IDENTIFICATION
9  * src/backend/replication/logical/proto.c
10  *
11  *-------------------------------------------------------------------------
12  */
13 #include "postgres.h"
14 
15 #include "access/sysattr.h"
16 #include "catalog/pg_namespace.h"
17 #include "catalog/pg_type.h"
18 #include "libpq/pqformat.h"
20 #include "utils/lsyscache.h"
21 #include "utils/syscache.h"
22 
23 /*
24  * Protocol message flags.
25  */
26 #define LOGICALREP_IS_REPLICA_IDENTITY 1
27 
28 #define MESSAGE_TRANSACTIONAL (1<<0)
29 #define TRUNCATE_CASCADE (1<<0)
30 #define TRUNCATE_RESTART_SEQS (1<<1)
31 
32 static void logicalrep_write_attrs(StringInfo out, Relation rel,
33  Bitmapset *columns);
34 static void logicalrep_write_tuple(StringInfo out, Relation rel,
35  TupleTableSlot *slot,
36  bool binary, Bitmapset *columns);
39 
40 static void logicalrep_write_namespace(StringInfo out, Oid nspid);
41 static const char *logicalrep_read_namespace(StringInfo in);
42 
43 /*
44  * Check if a column is covered by a column list.
45  *
46  * Need to be careful about NULL, which is treated as a column list covering
47  * all columns.
48  */
49 static bool
51 {
52  return (columns == NULL || bms_is_member(attnum, columns));
53 }
54 
55 
56 /*
57  * Write BEGIN to the output stream.
58  */
59 void
61 {
63 
64  /* fixed fields */
65  pq_sendint64(out, txn->final_lsn);
67  pq_sendint32(out, txn->xid);
68 }
69 
70 /*
71  * Read transaction BEGIN from the stream.
72  */
73 void
75 {
76  /* read fields */
77  begin_data->final_lsn = pq_getmsgint64(in);
78  if (begin_data->final_lsn == InvalidXLogRecPtr)
79  elog(ERROR, "final_lsn not set in begin message");
80  begin_data->committime = pq_getmsgint64(in);
81  begin_data->xid = pq_getmsgint(in, 4);
82 }
83 
84 
85 /*
86  * Write COMMIT to the output stream.
87  */
88 void
90  XLogRecPtr commit_lsn)
91 {
92  uint8 flags = 0;
93 
95 
96  /* send the flags field (unused for now) */
97  pq_sendbyte(out, flags);
98 
99  /* send fields */
100  pq_sendint64(out, commit_lsn);
101  pq_sendint64(out, txn->end_lsn);
103 }
104 
105 /*
106  * Read transaction COMMIT from the stream.
107  */
108 void
110 {
111  /* read flags (unused for now) */
112  uint8 flags = pq_getmsgbyte(in);
113 
114  if (flags != 0)
115  elog(ERROR, "unrecognized flags %u in commit message", flags);
116 
117  /* read fields */
118  commit_data->commit_lsn = pq_getmsgint64(in);
119  commit_data->end_lsn = pq_getmsgint64(in);
120  commit_data->committime = pq_getmsgint64(in);
121 }
122 
123 /*
124  * Write BEGIN PREPARE to the output stream.
125  */
126 void
128 {
130 
131  /* fixed fields */
132  pq_sendint64(out, txn->final_lsn);
133  pq_sendint64(out, txn->end_lsn);
135  pq_sendint32(out, txn->xid);
136 
137  /* send gid */
138  pq_sendstring(out, txn->gid);
139 }
140 
141 /*
142  * Read transaction BEGIN PREPARE from the stream.
143  */
144 void
146 {
147  /* read fields */
148  begin_data->prepare_lsn = pq_getmsgint64(in);
149  if (begin_data->prepare_lsn == InvalidXLogRecPtr)
150  elog(ERROR, "prepare_lsn not set in begin prepare message");
151  begin_data->end_lsn = pq_getmsgint64(in);
152  if (begin_data->end_lsn == InvalidXLogRecPtr)
153  elog(ERROR, "end_lsn not set in begin prepare message");
154  begin_data->prepare_time = pq_getmsgint64(in);
155  begin_data->xid = pq_getmsgint(in, 4);
156 
157  /* read gid (copy it into a pre-allocated buffer) */
158  strlcpy(begin_data->gid, pq_getmsgstring(in), sizeof(begin_data->gid));
159 }
160 
161 /*
162  * The core functionality for logicalrep_write_prepare and
163  * logicalrep_write_stream_prepare.
164  */
165 static void
167  ReorderBufferTXN *txn, XLogRecPtr prepare_lsn)
168 {
169  uint8 flags = 0;
170 
171  pq_sendbyte(out, type);
172 
173  /*
174  * This should only ever happen for two-phase commit transactions, in
175  * which case we expect to have a valid GID.
176  */
177  Assert(txn->gid != NULL);
178  Assert(rbtxn_prepared(txn));
180 
181  /* send the flags field */
182  pq_sendbyte(out, flags);
183 
184  /* send fields */
185  pq_sendint64(out, prepare_lsn);
186  pq_sendint64(out, txn->end_lsn);
188  pq_sendint32(out, txn->xid);
189 
190  /* send gid */
191  pq_sendstring(out, txn->gid);
192 }
193 
194 /*
195  * Write PREPARE to the output stream.
196  */
197 void
199  XLogRecPtr prepare_lsn)
200 {
202  txn, prepare_lsn);
203 }
204 
205 /*
206  * The core functionality for logicalrep_read_prepare and
207  * logicalrep_read_stream_prepare.
208  */
209 static void
211  LogicalRepPreparedTxnData *prepare_data)
212 {
213  /* read flags */
214  uint8 flags = pq_getmsgbyte(in);
215 
216  if (flags != 0)
217  elog(ERROR, "unrecognized flags %u in %s message", flags, msgtype);
218 
219  /* read fields */
220  prepare_data->prepare_lsn = pq_getmsgint64(in);
221  if (prepare_data->prepare_lsn == InvalidXLogRecPtr)
222  elog(ERROR, "prepare_lsn is not set in %s message", msgtype);
223  prepare_data->end_lsn = pq_getmsgint64(in);
224  if (prepare_data->end_lsn == InvalidXLogRecPtr)
225  elog(ERROR, "end_lsn is not set in %s message", msgtype);
226  prepare_data->prepare_time = pq_getmsgint64(in);
227  prepare_data->xid = pq_getmsgint(in, 4);
228  if (prepare_data->xid == InvalidTransactionId)
229  elog(ERROR, "invalid two-phase transaction ID in %s message", msgtype);
230 
231  /* read gid (copy it into a pre-allocated buffer) */
232  strlcpy(prepare_data->gid, pq_getmsgstring(in), sizeof(prepare_data->gid));
233 }
234 
235 /*
236  * Read transaction PREPARE from the stream.
237  */
238 void
240 {
241  logicalrep_read_prepare_common(in, "prepare", prepare_data);
242 }
243 
244 /*
245  * Write COMMIT PREPARED to the output stream.
246  */
247 void
249  XLogRecPtr commit_lsn)
250 {
251  uint8 flags = 0;
252 
254 
255  /*
256  * This should only ever happen for two-phase commit transactions, in
257  * which case we expect to have a valid GID.
258  */
259  Assert(txn->gid != NULL);
260 
261  /* send the flags field */
262  pq_sendbyte(out, flags);
263 
264  /* send fields */
265  pq_sendint64(out, commit_lsn);
266  pq_sendint64(out, txn->end_lsn);
268  pq_sendint32(out, txn->xid);
269 
270  /* send gid */
271  pq_sendstring(out, txn->gid);
272 }
273 
274 /*
275  * Read transaction COMMIT PREPARED from the stream.
276  */
277 void
279 {
280  /* read flags */
281  uint8 flags = pq_getmsgbyte(in);
282 
283  if (flags != 0)
284  elog(ERROR, "unrecognized flags %u in commit prepared message", flags);
285 
286  /* read fields */
287  prepare_data->commit_lsn = pq_getmsgint64(in);
288  if (prepare_data->commit_lsn == InvalidXLogRecPtr)
289  elog(ERROR, "commit_lsn is not set in commit prepared message");
290  prepare_data->end_lsn = pq_getmsgint64(in);
291  if (prepare_data->end_lsn == InvalidXLogRecPtr)
292  elog(ERROR, "end_lsn is not set in commit prepared message");
293  prepare_data->commit_time = pq_getmsgint64(in);
294  prepare_data->xid = pq_getmsgint(in, 4);
295 
296  /* read gid (copy it into a pre-allocated buffer) */
297  strlcpy(prepare_data->gid, pq_getmsgstring(in), sizeof(prepare_data->gid));
298 }
299 
300 /*
301  * Write ROLLBACK PREPARED to the output stream.
302  */
303 void
305  XLogRecPtr prepare_end_lsn,
306  TimestampTz prepare_time)
307 {
308  uint8 flags = 0;
309 
311 
312  /*
313  * This should only ever happen for two-phase commit transactions, in
314  * which case we expect to have a valid GID.
315  */
316  Assert(txn->gid != NULL);
317 
318  /* send the flags field */
319  pq_sendbyte(out, flags);
320 
321  /* send fields */
322  pq_sendint64(out, prepare_end_lsn);
323  pq_sendint64(out, txn->end_lsn);
324  pq_sendint64(out, prepare_time);
326  pq_sendint32(out, txn->xid);
327 
328  /* send gid */
329  pq_sendstring(out, txn->gid);
330 }
331 
332 /*
333  * Read transaction ROLLBACK PREPARED from the stream.
334  */
335 void
337  LogicalRepRollbackPreparedTxnData *rollback_data)
338 {
339  /* read flags */
340  uint8 flags = pq_getmsgbyte(in);
341 
342  if (flags != 0)
343  elog(ERROR, "unrecognized flags %u in rollback prepared message", flags);
344 
345  /* read fields */
346  rollback_data->prepare_end_lsn = pq_getmsgint64(in);
347  if (rollback_data->prepare_end_lsn == InvalidXLogRecPtr)
348  elog(ERROR, "prepare_end_lsn is not set in rollback prepared message");
349  rollback_data->rollback_end_lsn = pq_getmsgint64(in);
350  if (rollback_data->rollback_end_lsn == InvalidXLogRecPtr)
351  elog(ERROR, "rollback_end_lsn is not set in rollback prepared message");
352  rollback_data->prepare_time = pq_getmsgint64(in);
353  rollback_data->rollback_time = pq_getmsgint64(in);
354  rollback_data->xid = pq_getmsgint(in, 4);
355 
356  /* read gid (copy it into a pre-allocated buffer) */
357  strlcpy(rollback_data->gid, pq_getmsgstring(in), sizeof(rollback_data->gid));
358 }
359 
360 /*
361  * Write STREAM PREPARE to the output stream.
362  */
363 void
365  ReorderBufferTXN *txn,
366  XLogRecPtr prepare_lsn)
367 {
369  txn, prepare_lsn);
370 }
371 
372 /*
373  * Read STREAM PREPARE from the stream.
374  */
375 void
377 {
378  logicalrep_read_prepare_common(in, "stream prepare", prepare_data);
379 }
380 
381 /*
382  * Write ORIGIN to the output stream.
383  */
384 void
385 logicalrep_write_origin(StringInfo out, const char *origin,
386  XLogRecPtr origin_lsn)
387 {
389 
390  /* fixed fields */
391  pq_sendint64(out, origin_lsn);
392 
393  /* origin string */
394  pq_sendstring(out, origin);
395 }
396 
397 /*
398  * Read ORIGIN from the output stream.
399  */
400 char *
402 {
403  /* fixed fields */
404  *origin_lsn = pq_getmsgint64(in);
405 
406  /* return origin */
407  return pstrdup(pq_getmsgstring(in));
408 }
409 
410 /*
411  * Write INSERT to the output stream.
412  */
413 void
415  TupleTableSlot *newslot, bool binary, Bitmapset *columns)
416 {
418 
419  /* transaction ID (if not valid, we're not streaming) */
420  if (TransactionIdIsValid(xid))
421  pq_sendint32(out, xid);
422 
423  /* use Oid as relation identifier */
424  pq_sendint32(out, RelationGetRelid(rel));
425 
426  pq_sendbyte(out, 'N'); /* new tuple follows */
427  logicalrep_write_tuple(out, rel, newslot, binary, columns);
428 }
429 
430 /*
431  * Read INSERT from stream.
432  *
433  * Fills the new tuple.
434  */
437 {
438  char action;
439  LogicalRepRelId relid;
440 
441  /* read the relation id */
442  relid = pq_getmsgint(in, 4);
443 
444  action = pq_getmsgbyte(in);
445  if (action != 'N')
446  elog(ERROR, "expected new tuple but got %d",
447  action);
448 
449  logicalrep_read_tuple(in, newtup);
450 
451  return relid;
452 }
453 
454 /*
455  * Write UPDATE to the output stream.
456  */
457 void
459  TupleTableSlot *oldslot, TupleTableSlot *newslot,
460  bool binary, Bitmapset *columns)
461 {
463 
464  Assert(rel->rd_rel->relreplident == REPLICA_IDENTITY_DEFAULT ||
465  rel->rd_rel->relreplident == REPLICA_IDENTITY_FULL ||
466  rel->rd_rel->relreplident == REPLICA_IDENTITY_INDEX);
467 
468  /* transaction ID (if not valid, we're not streaming) */
469  if (TransactionIdIsValid(xid))
470  pq_sendint32(out, xid);
471 
472  /* use Oid as relation identifier */
473  pq_sendint32(out, RelationGetRelid(rel));
474 
475  if (oldslot != NULL)
476  {
477  if (rel->rd_rel->relreplident == REPLICA_IDENTITY_FULL)
478  pq_sendbyte(out, 'O'); /* old tuple follows */
479  else
480  pq_sendbyte(out, 'K'); /* old key follows */
481  logicalrep_write_tuple(out, rel, oldslot, binary, NULL);
482  }
483 
484  pq_sendbyte(out, 'N'); /* new tuple follows */
485  logicalrep_write_tuple(out, rel, newslot, binary, columns);
486 }
487 
488 /*
489  * Read UPDATE from stream.
490  */
492 logicalrep_read_update(StringInfo in, bool *has_oldtuple,
493  LogicalRepTupleData *oldtup,
494  LogicalRepTupleData *newtup)
495 {
496  char action;
497  LogicalRepRelId relid;
498 
499  /* read the relation id */
500  relid = pq_getmsgint(in, 4);
501 
502  /* read and verify action */
503  action = pq_getmsgbyte(in);
504  if (action != 'K' && action != 'O' && action != 'N')
505  elog(ERROR, "expected action 'N', 'O' or 'K', got %c",
506  action);
507 
508  /* check for old tuple */
509  if (action == 'K' || action == 'O')
510  {
511  logicalrep_read_tuple(in, oldtup);
512  *has_oldtuple = true;
513 
514  action = pq_getmsgbyte(in);
515  }
516  else
517  *has_oldtuple = false;
518 
519  /* check for new tuple */
520  if (action != 'N')
521  elog(ERROR, "expected action 'N', got %c",
522  action);
523 
524  logicalrep_read_tuple(in, newtup);
525 
526  return relid;
527 }
528 
529 /*
530  * Write DELETE to the output stream.
531  */
532 void
534  TupleTableSlot *oldslot, bool binary)
535 {
536  Assert(rel->rd_rel->relreplident == REPLICA_IDENTITY_DEFAULT ||
537  rel->rd_rel->relreplident == REPLICA_IDENTITY_FULL ||
538  rel->rd_rel->relreplident == REPLICA_IDENTITY_INDEX);
539 
541 
542  /* transaction ID (if not valid, we're not streaming) */
543  if (TransactionIdIsValid(xid))
544  pq_sendint32(out, xid);
545 
546  /* use Oid as relation identifier */
547  pq_sendint32(out, RelationGetRelid(rel));
548 
549  if (rel->rd_rel->relreplident == REPLICA_IDENTITY_FULL)
550  pq_sendbyte(out, 'O'); /* old tuple follows */
551  else
552  pq_sendbyte(out, 'K'); /* old key follows */
553 
554  logicalrep_write_tuple(out, rel, oldslot, binary, NULL);
555 }
556 
557 /*
558  * Read DELETE from stream.
559  *
560  * Fills the old tuple.
561  */
564 {
565  char action;
566  LogicalRepRelId relid;
567 
568  /* read the relation id */
569  relid = pq_getmsgint(in, 4);
570 
571  /* read and verify action */
572  action = pq_getmsgbyte(in);
573  if (action != 'K' && action != 'O')
574  elog(ERROR, "expected action 'O' or 'K', got %c", action);
575 
576  logicalrep_read_tuple(in, oldtup);
577 
578  return relid;
579 }
580 
581 /*
582  * Write TRUNCATE to the output stream.
583  */
584 void
586  TransactionId xid,
587  int nrelids,
588  Oid relids[],
589  bool cascade, bool restart_seqs)
590 {
591  int i;
592  uint8 flags = 0;
593 
595 
596  /* transaction ID (if not valid, we're not streaming) */
597  if (TransactionIdIsValid(xid))
598  pq_sendint32(out, xid);
599 
600  pq_sendint32(out, nrelids);
601 
602  /* encode and send truncate flags */
603  if (cascade)
604  flags |= TRUNCATE_CASCADE;
605  if (restart_seqs)
606  flags |= TRUNCATE_RESTART_SEQS;
607  pq_sendint8(out, flags);
608 
609  for (i = 0; i < nrelids; i++)
610  pq_sendint32(out, relids[i]);
611 }
612 
613 /*
614  * Read TRUNCATE from stream.
615  */
616 List *
618  bool *cascade, bool *restart_seqs)
619 {
620  int i;
621  int nrelids;
622  List *relids = NIL;
623  uint8 flags;
624 
625  nrelids = pq_getmsgint(in, 4);
626 
627  /* read and decode truncate flags */
628  flags = pq_getmsgint(in, 1);
629  *cascade = (flags & TRUNCATE_CASCADE) > 0;
630  *restart_seqs = (flags & TRUNCATE_RESTART_SEQS) > 0;
631 
632  for (i = 0; i < nrelids; i++)
633  relids = lappend_oid(relids, pq_getmsgint(in, 4));
634 
635  return relids;
636 }
637 
638 /*
639  * Write MESSAGE to stream
640  */
641 void
643  bool transactional, const char *prefix, Size sz,
644  const char *message)
645 {
646  uint8 flags = 0;
647 
649 
650  /* encode and send message flags */
651  if (transactional)
652  flags |= MESSAGE_TRANSACTIONAL;
653 
654  /* transaction ID (if not valid, we're not streaming) */
655  if (TransactionIdIsValid(xid))
656  pq_sendint32(out, xid);
657 
658  pq_sendint8(out, flags);
659  pq_sendint64(out, lsn);
660  pq_sendstring(out, prefix);
661  pq_sendint32(out, sz);
662  pq_sendbytes(out, message, sz);
663 }
664 
665 /*
666  * Write relation description to the output stream.
667  */
668 void
670  Bitmapset *columns)
671 {
672  char *relname;
673 
675 
676  /* transaction ID (if not valid, we're not streaming) */
677  if (TransactionIdIsValid(xid))
678  pq_sendint32(out, xid);
679 
680  /* use Oid as relation identifier */
681  pq_sendint32(out, RelationGetRelid(rel));
682 
683  /* send qualified relation name */
686  pq_sendstring(out, relname);
687 
688  /* send replica identity */
689  pq_sendbyte(out, rel->rd_rel->relreplident);
690 
691  /* send the attribute info */
692  logicalrep_write_attrs(out, rel, columns);
693 }
694 
695 /*
696  * Read the relation info from stream and return as LogicalRepRelation.
697  */
700 {
702 
703  rel->remoteid = pq_getmsgint(in, 4);
704 
705  /* Read relation name from stream */
707  rel->relname = pstrdup(pq_getmsgstring(in));
708 
709  /* Read the replica identity. */
710  rel->replident = pq_getmsgbyte(in);
711 
712  /* Get attribute description */
713  logicalrep_read_attrs(in, rel);
714 
715  return rel;
716 }
717 
718 /*
719  * Write type info to the output stream.
720  *
721  * This function will always write base type info.
722  */
723 void
725 {
726  Oid basetypoid = getBaseType(typoid);
727  HeapTuple tup;
728  Form_pg_type typtup;
729 
731 
732  /* transaction ID (if not valid, we're not streaming) */
733  if (TransactionIdIsValid(xid))
734  pq_sendint32(out, xid);
735 
736  tup = SearchSysCache1(TYPEOID, ObjectIdGetDatum(basetypoid));
737  if (!HeapTupleIsValid(tup))
738  elog(ERROR, "cache lookup failed for type %u", basetypoid);
739  typtup = (Form_pg_type) GETSTRUCT(tup);
740 
741  /* use Oid as relation identifier */
742  pq_sendint32(out, typoid);
743 
744  /* send qualified type name */
745  logicalrep_write_namespace(out, typtup->typnamespace);
746  pq_sendstring(out, NameStr(typtup->typname));
747 
748  ReleaseSysCache(tup);
749 }
750 
751 /*
752  * Read type info from the output stream.
753  */
754 void
756 {
757  ltyp->remoteid = pq_getmsgint(in, 4);
758 
759  /* Read type name from stream */
761  ltyp->typname = pstrdup(pq_getmsgstring(in));
762 }
763 
764 /*
765  * Write a tuple to the outputstream, in the most efficient format possible.
766  */
767 static void
769  bool binary, Bitmapset *columns)
770 {
771  TupleDesc desc;
772  Datum *values;
773  bool *isnull;
774  int i;
775  uint16 nliveatts = 0;
776 
777  desc = RelationGetDescr(rel);
778 
779  for (i = 0; i < desc->natts; i++)
780  {
781  Form_pg_attribute att = TupleDescAttr(desc, i);
782 
783  if (att->attisdropped || att->attgenerated)
784  continue;
785 
786  if (!column_in_column_list(att->attnum, columns))
787  continue;
788 
789  nliveatts++;
790  }
791  pq_sendint16(out, nliveatts);
792 
793  slot_getallattrs(slot);
794  values = slot->tts_values;
795  isnull = slot->tts_isnull;
796 
797  /* Write the values */
798  for (i = 0; i < desc->natts; i++)
799  {
800  HeapTuple typtup;
801  Form_pg_type typclass;
802  Form_pg_attribute att = TupleDescAttr(desc, i);
803 
804  if (att->attisdropped || att->attgenerated)
805  continue;
806 
807  if (!column_in_column_list(att->attnum, columns))
808  continue;
809 
810  if (isnull[i])
811  {
813  continue;
814  }
815 
816  if (att->attlen == -1 && VARATT_IS_EXTERNAL_ONDISK(values[i]))
817  {
818  /*
819  * Unchanged toasted datum. (Note that we don't promise to detect
820  * unchanged data in general; this is just a cheap check to avoid
821  * sending large values unnecessarily.)
822  */
824  continue;
825  }
826 
827  typtup = SearchSysCache1(TYPEOID, ObjectIdGetDatum(att->atttypid));
828  if (!HeapTupleIsValid(typtup))
829  elog(ERROR, "cache lookup failed for type %u", att->atttypid);
830  typclass = (Form_pg_type) GETSTRUCT(typtup);
831 
832  /*
833  * Send in binary if requested and type has suitable send function.
834  */
835  if (binary && OidIsValid(typclass->typsend))
836  {
837  bytea *outputbytes;
838  int len;
839 
841  outputbytes = OidSendFunctionCall(typclass->typsend, values[i]);
842  len = VARSIZE(outputbytes) - VARHDRSZ;
843  pq_sendint(out, len, 4); /* length */
844  pq_sendbytes(out, VARDATA(outputbytes), len); /* data */
845  pfree(outputbytes);
846  }
847  else
848  {
849  char *outputstr;
850 
852  outputstr = OidOutputFunctionCall(typclass->typoutput, values[i]);
853  pq_sendcountedtext(out, outputstr, strlen(outputstr), false);
854  pfree(outputstr);
855  }
856 
857  ReleaseSysCache(typtup);
858  }
859 }
860 
861 /*
862  * Read tuple in logical replication format from stream.
863  */
864 static void
866 {
867  int i;
868  int natts;
869 
870  /* Get number of attributes */
871  natts = pq_getmsgint(in, 2);
872 
873  /* Allocate space for per-column values; zero out unused StringInfoDatas */
874  tuple->colvalues = (StringInfoData *) palloc0(natts * sizeof(StringInfoData));
875  tuple->colstatus = (char *) palloc(natts * sizeof(char));
876  tuple->ncols = natts;
877 
878  /* Read the data */
879  for (i = 0; i < natts; i++)
880  {
881  char kind;
882  int len;
883  StringInfo value = &tuple->colvalues[i];
884 
885  kind = pq_getmsgbyte(in);
886  tuple->colstatus[i] = kind;
887 
888  switch (kind)
889  {
891  /* nothing more to do */
892  break;
894  /* we don't receive the value of an unchanged column */
895  break;
897  len = pq_getmsgint(in, 4); /* read length */
898 
899  /* and data */
900  value->data = palloc(len + 1);
901  pq_copymsgbytes(in, value->data, len);
902  value->data[len] = '\0';
903  /* make StringInfo fully valid */
904  value->len = len;
905  value->cursor = 0;
906  value->maxlen = len;
907  break;
909  len = pq_getmsgint(in, 4); /* read length */
910 
911  /* and data */
912  value->data = palloc(len + 1);
913  pq_copymsgbytes(in, value->data, len);
914  /* not strictly necessary but per StringInfo practice */
915  value->data[len] = '\0';
916  /* make StringInfo fully valid */
917  value->len = len;
918  value->cursor = 0;
919  value->maxlen = len;
920  break;
921  default:
922  elog(ERROR, "unrecognized data representation type '%c'", kind);
923  }
924  }
925 }
926 
927 /*
928  * Write relation attribute metadata to the stream.
929  */
930 static void
932 {
933  TupleDesc desc;
934  int i;
935  uint16 nliveatts = 0;
936  Bitmapset *idattrs = NULL;
937  bool replidentfull;
938 
939  desc = RelationGetDescr(rel);
940 
941  /* send number of live attributes */
942  for (i = 0; i < desc->natts; i++)
943  {
944  Form_pg_attribute att = TupleDescAttr(desc, i);
945 
946  if (att->attisdropped || att->attgenerated)
947  continue;
948 
949  if (!column_in_column_list(att->attnum, columns))
950  continue;
951 
952  nliveatts++;
953  }
954  pq_sendint16(out, nliveatts);
955 
956  /* fetch bitmap of REPLICATION IDENTITY attributes */
957  replidentfull = (rel->rd_rel->relreplident == REPLICA_IDENTITY_FULL);
958  if (!replidentfull)
959  idattrs = RelationGetIdentityKeyBitmap(rel);
960 
961  /* send the attributes */
962  for (i = 0; i < desc->natts; i++)
963  {
964  Form_pg_attribute att = TupleDescAttr(desc, i);
965  uint8 flags = 0;
966 
967  if (att->attisdropped || att->attgenerated)
968  continue;
969 
970  if (!column_in_column_list(att->attnum, columns))
971  continue;
972 
973  /* REPLICA IDENTITY FULL means all columns are sent as part of key. */
974  if (replidentfull ||
976  idattrs))
978 
979  pq_sendbyte(out, flags);
980 
981  /* attribute name */
982  pq_sendstring(out, NameStr(att->attname));
983 
984  /* attribute type id */
985  pq_sendint32(out, (int) att->atttypid);
986 
987  /* attribute mode */
988  pq_sendint32(out, att->atttypmod);
989  }
990 
991  bms_free(idattrs);
992 }
993 
994 /*
995  * Read relation attribute metadata from the stream.
996  */
997 static void
999 {
1000  int i;
1001  int natts;
1002  char **attnames;
1003  Oid *atttyps;
1004  Bitmapset *attkeys = NULL;
1005 
1006  natts = pq_getmsgint(in, 2);
1007  attnames = palloc(natts * sizeof(char *));
1008  atttyps = palloc(natts * sizeof(Oid));
1009 
1010  /* read the attributes */
1011  for (i = 0; i < natts; i++)
1012  {
1013  uint8 flags;
1014 
1015  /* Check for replica identity column */
1016  flags = pq_getmsgbyte(in);
1017  if (flags & LOGICALREP_IS_REPLICA_IDENTITY)
1018  attkeys = bms_add_member(attkeys, i);
1019 
1020  /* attribute name */
1021  attnames[i] = pstrdup(pq_getmsgstring(in));
1022 
1023  /* attribute type id */
1024  atttyps[i] = (Oid) pq_getmsgint(in, 4);
1025 
1026  /* we ignore attribute mode for now */
1027  (void) pq_getmsgint(in, 4);
1028  }
1029 
1030  rel->attnames = attnames;
1031  rel->atttyps = atttyps;
1032  rel->attkeys = attkeys;
1033  rel->natts = natts;
1034 }
1035 
1036 /*
1037  * Write the namespace name or empty string for pg_catalog (to save space).
1038  */
1039 static void
1041 {
1042  if (nspid == PG_CATALOG_NAMESPACE)
1043  pq_sendbyte(out, '\0');
1044  else
1045  {
1046  char *nspname = get_namespace_name(nspid);
1047 
1048  if (nspname == NULL)
1049  elog(ERROR, "cache lookup failed for namespace %u",
1050  nspid);
1051 
1052  pq_sendstring(out, nspname);
1053  }
1054 }
1055 
1056 /*
1057  * Read the namespace name while treating empty string as pg_catalog.
1058  */
1059 static const char *
1061 {
1062  const char *nspname = pq_getmsgstring(in);
1063 
1064  if (nspname[0] == '\0')
1065  nspname = "pg_catalog";
1066 
1067  return nspname;
1068 }
1069 
1070 /*
1071  * Write the information for the start stream message to the output stream.
1072  */
1073 void
1075  TransactionId xid, bool first_segment)
1076 {
1078 
1080 
1081  /* transaction ID (we're starting to stream, so must be valid) */
1082  pq_sendint32(out, xid);
1083 
1084  /* 1 if this is the first streaming segment for this xid */
1085  pq_sendbyte(out, first_segment ? 1 : 0);
1086 }
1087 
1088 /*
1089  * Read the information about the start stream message from output stream.
1090  */
1093 {
1094  TransactionId xid;
1095 
1096  Assert(first_segment);
1097 
1098  xid = pq_getmsgint(in, 4);
1099  *first_segment = (pq_getmsgbyte(in) == 1);
1100 
1101  return xid;
1102 }
1103 
1104 /*
1105  * Write the stop stream message to the output stream.
1106  */
1107 void
1109 {
1111 }
1112 
1113 /*
1114  * Write STREAM COMMIT to the output stream.
1115  */
1116 void
1118  XLogRecPtr commit_lsn)
1119 {
1120  uint8 flags = 0;
1121 
1123 
1125 
1126  /* transaction ID */
1127  pq_sendint32(out, txn->xid);
1128 
1129  /* send the flags field (unused for now) */
1130  pq_sendbyte(out, flags);
1131 
1132  /* send fields */
1133  pq_sendint64(out, commit_lsn);
1134  pq_sendint64(out, txn->end_lsn);
1135  pq_sendint64(out, txn->xact_time.commit_time);
1136 }
1137 
1138 /*
1139  * Read STREAM COMMIT from the output stream.
1140  */
1143 {
1144  TransactionId xid;
1145  uint8 flags;
1146 
1147  xid = pq_getmsgint(in, 4);
1148 
1149  /* read flags (unused for now) */
1150  flags = pq_getmsgbyte(in);
1151 
1152  if (flags != 0)
1153  elog(ERROR, "unrecognized flags %u in commit message", flags);
1154 
1155  /* read fields */
1156  commit_data->commit_lsn = pq_getmsgint64(in);
1157  commit_data->end_lsn = pq_getmsgint64(in);
1158  commit_data->committime = pq_getmsgint64(in);
1159 
1160  return xid;
1161 }
1162 
1163 /*
1164  * Write STREAM ABORT to the output stream. Note that xid and subxid will be
1165  * same for the top-level transaction abort.
1166  */
1167 void
1169  TransactionId subxid)
1170 {
1172 
1174 
1175  /* transaction ID */
1176  pq_sendint32(out, xid);
1177  pq_sendint32(out, subxid);
1178 }
1179 
1180 /*
1181  * Read STREAM ABORT from the output stream.
1182  */
1183 void
1185  TransactionId *subxid)
1186 {
1187  Assert(xid && subxid);
1188 
1189  *xid = pq_getmsgint(in, 4);
1190  *subxid = pq_getmsgint(in, 4);
1191 }
1192 
1193 /*
1194  * Get string representing LogicalRepMsgType.
1195  */
1196 char *
1198 {
1199  switch (action)
1200  {
1201  case LOGICAL_REP_MSG_BEGIN:
1202  return "BEGIN";
1204  return "COMMIT";
1206  return "ORIGIN";
1208  return "INSERT";
1210  return "UPDATE";
1212  return "DELETE";
1214  return "TRUNCATE";
1216  return "RELATION";
1217  case LOGICAL_REP_MSG_TYPE:
1218  return "TYPE";
1220  return "MESSAGE";
1222  return "BEGIN PREPARE";
1224  return "PREPARE";
1226  return "COMMIT PREPARED";
1228  return "ROLLBACK PREPARED";
1230  return "STREAM START";
1232  return "STREAM STOP";
1234  return "STREAM COMMIT";
1236  return "STREAM ABORT";
1238  return "STREAM PREPARE";
1239  }
1240 
1241  elog(ERROR, "invalid logical replication message type \"%c\"", action);
1242 
1243  return NULL; /* keep compiler quiet */
1244 }
void bms_free(Bitmapset *a)
Definition: bitmapset.c:208
bool bms_is_member(int x, const Bitmapset *a)
Definition: bitmapset.c:427
Bitmapset * bms_add_member(Bitmapset *a, int x)
Definition: bitmapset.c:738
static Datum values[MAXATTR]
Definition: bootstrap.c:156
#define NameStr(name)
Definition: c.h:681
unsigned short uint16
Definition: c.h:440
#define VARHDRSZ
Definition: c.h:627
unsigned char uint8
Definition: c.h:439
uint32 TransactionId
Definition: c.h:587
#define OidIsValid(objectId)
Definition: c.h:710
size_t Size
Definition: c.h:540
int64 TimestampTz
Definition: timestamp.h:39
#define ERROR
Definition: elog.h:33
#define elog(elevel,...)
Definition: elog.h:218
char * OidOutputFunctionCall(Oid functionId, Datum val)
Definition: fmgr.c:1639
bytea * OidSendFunctionCall(Oid functionId, Datum val)
Definition: fmgr.c:1658
#define HeapTupleIsValid(tuple)
Definition: htup.h:78
#define GETSTRUCT(TUP)
Definition: htup_details.h:649
static struct @151 value
int i
Definition: isn.c:73
Assert(fmt[strlen(fmt) - 1] !='\n')
List * lappend_oid(List *list, Oid datum)
Definition: list.c:372
#define LOGICALREP_COLUMN_UNCHANGED
Definition: logicalproto.h:92
LogicalRepMsgType
Definition: logicalproto.h:53
@ LOGICAL_REP_MSG_INSERT
Definition: logicalproto.h:57
@ LOGICAL_REP_MSG_TRUNCATE
Definition: logicalproto.h:60
@ LOGICAL_REP_MSG_STREAM_STOP
Definition: logicalproto.h:69
@ LOGICAL_REP_MSG_BEGIN
Definition: logicalproto.h:54
@ LOGICAL_REP_MSG_STREAM_PREPARE
Definition: logicalproto.h:72
@ LOGICAL_REP_MSG_STREAM_ABORT
Definition: logicalproto.h:71
@ LOGICAL_REP_MSG_BEGIN_PREPARE
Definition: logicalproto.h:64
@ LOGICAL_REP_MSG_STREAM_START
Definition: logicalproto.h:68
@ LOGICAL_REP_MSG_COMMIT
Definition: logicalproto.h:55
@ LOGICAL_REP_MSG_PREPARE
Definition: logicalproto.h:65
@ LOGICAL_REP_MSG_RELATION
Definition: logicalproto.h:61
@ LOGICAL_REP_MSG_MESSAGE
Definition: logicalproto.h:63
@ LOGICAL_REP_MSG_ROLLBACK_PREPARED
Definition: logicalproto.h:67
@ LOGICAL_REP_MSG_COMMIT_PREPARED
Definition: logicalproto.h:66
@ LOGICAL_REP_MSG_TYPE
Definition: logicalproto.h:62
@ LOGICAL_REP_MSG_DELETE
Definition: logicalproto.h:59
@ LOGICAL_REP_MSG_STREAM_COMMIT
Definition: logicalproto.h:70
@ LOGICAL_REP_MSG_ORIGIN
Definition: logicalproto.h:56
@ LOGICAL_REP_MSG_UPDATE
Definition: logicalproto.h:58
uint32 LogicalRepRelId
Definition: logicalproto.h:96
#define LOGICALREP_COLUMN_NULL
Definition: logicalproto.h:91
#define LOGICALREP_COLUMN_BINARY
Definition: logicalproto.h:94
#define LOGICALREP_COLUMN_TEXT
Definition: logicalproto.h:93
char * get_namespace_name(Oid nspid)
Definition: lsyscache.c:3326
Oid getBaseType(Oid typid)
Definition: lsyscache.c:2478
char * pstrdup(const char *in)
Definition: mcxt.c:1305
void pfree(void *pointer)
Definition: mcxt.c:1175
void * palloc0(Size size)
Definition: mcxt.c:1099
void * palloc(Size size)
Definition: mcxt.c:1068
int16 attnum
Definition: pg_attribute.h:83
FormData_pg_attribute * Form_pg_attribute
Definition: pg_attribute.h:207
NameData relname
Definition: pg_class.h:38
const void size_t len
#define NIL
Definition: pg_list.h:65
FormData_pg_type * Form_pg_type
Definition: pg_type.h:261
size_t strlcpy(char *dst, const char *src, size_t siz)
Definition: strlcpy.c:45
#define VARATT_IS_EXTERNAL_ONDISK(PTR)
Definition: postgres.h:327
uintptr_t Datum
Definition: postgres.h:411
#define VARDATA(PTR)
Definition: postgres.h:315
#define ObjectIdGetDatum(X)
Definition: postgres.h:551
#define VARSIZE(PTR)
Definition: postgres.h:316
unsigned int Oid
Definition: postgres_ext.h:31
unsigned int pq_getmsgint(StringInfo msg, int b)
Definition: pqformat.c:417
const char * pq_getmsgstring(StringInfo msg)
Definition: pqformat.c:581
void pq_copymsgbytes(StringInfo msg, char *buf, int datalen)
Definition: pqformat.c:530
void pq_sendstring(StringInfo buf, const char *str)
Definition: pqformat.c:197
int pq_getmsgbyte(StringInfo msg)
Definition: pqformat.c:401
int64 pq_getmsgint64(StringInfo msg)
Definition: pqformat.c:455
void pq_sendbytes(StringInfo buf, const char *data, int datalen)
Definition: pqformat.c:125
void pq_sendcountedtext(StringInfo buf, const char *str, int slen, bool countincludesself)
Definition: pqformat.c:142
static void pq_sendint32(StringInfo buf, uint32 i)
Definition: pqformat.h:145
static void pq_sendbyte(StringInfo buf, uint8 byt)
Definition: pqformat.h:161
static void pq_sendint64(StringInfo buf, uint64 i)
Definition: pqformat.h:153
static void pq_sendint8(StringInfo buf, uint8 i)
Definition: pqformat.h:129
static void pq_sendint16(StringInfo buf, uint16 i)
Definition: pqformat.h:137
static void pq_sendint(StringInfo buf, uint32 i, int b)
Definition: pqformat.h:172
void logicalrep_read_commit(StringInfo in, LogicalRepCommitData *commit_data)
Definition: proto.c:109
static void logicalrep_write_namespace(StringInfo out, Oid nspid)
Definition: proto.c:1040
#define TRUNCATE_RESTART_SEQS
Definition: proto.c:30
LogicalRepRelId logicalrep_read_delete(StringInfo in, LogicalRepTupleData *oldtup)
Definition: proto.c:563
void logicalrep_write_commit(StringInfo out, ReorderBufferTXN *txn, XLogRecPtr commit_lsn)
Definition: proto.c:89
void logicalrep_write_rollback_prepared(StringInfo out, ReorderBufferTXN *txn, XLogRecPtr prepare_end_lsn, TimestampTz prepare_time)
Definition: proto.c:304
void logicalrep_read_rollback_prepared(StringInfo in, LogicalRepRollbackPreparedTxnData *rollback_data)
Definition: proto.c:336
static void logicalrep_write_prepare_common(StringInfo out, LogicalRepMsgType type, ReorderBufferTXN *txn, XLogRecPtr prepare_lsn)
Definition: proto.c:166
void logicalrep_write_origin(StringInfo out, const char *origin, XLogRecPtr origin_lsn)
Definition: proto.c:385
void logicalrep_read_begin_prepare(StringInfo in, LogicalRepPreparedTxnData *begin_data)
Definition: proto.c:145
static void logicalrep_write_attrs(StringInfo out, Relation rel, Bitmapset *columns)
Definition: proto.c:931
static void logicalrep_read_prepare_common(StringInfo in, char *msgtype, LogicalRepPreparedTxnData *prepare_data)
Definition: proto.c:210
List * logicalrep_read_truncate(StringInfo in, bool *cascade, bool *restart_seqs)
Definition: proto.c:617
char * logicalrep_message_type(LogicalRepMsgType action)
Definition: proto.c:1197
void logicalrep_read_typ(StringInfo in, LogicalRepTyp *ltyp)
Definition: proto.c:755
void logicalrep_write_rel(StringInfo out, TransactionId xid, Relation rel, Bitmapset *columns)
Definition: proto.c:669
LogicalRepRelId logicalrep_read_update(StringInfo in, bool *has_oldtuple, LogicalRepTupleData *oldtup, LogicalRepTupleData *newtup)
Definition: proto.c:492
void logicalrep_write_delete(StringInfo out, TransactionId xid, Relation rel, TupleTableSlot *oldslot, bool binary)
Definition: proto.c:533
void logicalrep_write_message(StringInfo out, TransactionId xid, XLogRecPtr lsn, bool transactional, const char *prefix, Size sz, const char *message)
Definition: proto.c:642
void logicalrep_write_update(StringInfo out, TransactionId xid, Relation rel, TupleTableSlot *oldslot, TupleTableSlot *newslot, bool binary, Bitmapset *columns)
Definition: proto.c:458
static void logicalrep_read_attrs(StringInfo in, LogicalRepRelation *rel)
Definition: proto.c:998
void logicalrep_write_prepare(StringInfo out, ReorderBufferTXN *txn, XLogRecPtr prepare_lsn)
Definition: proto.c:198
void logicalrep_read_begin(StringInfo in, LogicalRepBeginData *begin_data)
Definition: proto.c:74
void logicalrep_write_insert(StringInfo out, TransactionId xid, Relation rel, TupleTableSlot *newslot, bool binary, Bitmapset *columns)
Definition: proto.c:414
#define MESSAGE_TRANSACTIONAL
Definition: proto.c:28
void logicalrep_write_typ(StringInfo out, TransactionId xid, Oid typoid)
Definition: proto.c:724
void logicalrep_write_truncate(StringInfo out, TransactionId xid, int nrelids, Oid relids[], bool cascade, bool restart_seqs)
Definition: proto.c:585
#define LOGICALREP_IS_REPLICA_IDENTITY
Definition: proto.c:26
static void logicalrep_read_tuple(StringInfo in, LogicalRepTupleData *tuple)
Definition: proto.c:865
void logicalrep_write_begin(StringInfo out, ReorderBufferTXN *txn)
Definition: proto.c:60
void logicalrep_read_commit_prepared(StringInfo in, LogicalRepCommitPreparedTxnData *prepare_data)
Definition: proto.c:278
LogicalRepRelation * logicalrep_read_rel(StringInfo in)
Definition: proto.c:699
void logicalrep_write_commit_prepared(StringInfo out, ReorderBufferTXN *txn, XLogRecPtr commit_lsn)
Definition: proto.c:248
void logicalrep_write_stream_commit(StringInfo out, ReorderBufferTXN *txn, XLogRecPtr commit_lsn)
Definition: proto.c:1117
void logicalrep_write_stream_prepare(StringInfo out, ReorderBufferTXN *txn, XLogRecPtr prepare_lsn)
Definition: proto.c:364
void logicalrep_write_stream_abort(StringInfo out, TransactionId xid, TransactionId subxid)
Definition: proto.c:1168
#define TRUNCATE_CASCADE
Definition: proto.c:29
void logicalrep_read_stream_abort(StringInfo in, TransactionId *xid, TransactionId *subxid)
Definition: proto.c:1184
void logicalrep_write_begin_prepare(StringInfo out, ReorderBufferTXN *txn)
Definition: proto.c:127
void logicalrep_read_stream_prepare(StringInfo in, LogicalRepPreparedTxnData *prepare_data)
Definition: proto.c:376
void logicalrep_write_stream_start(StringInfo out, TransactionId xid, bool first_segment)
Definition: proto.c:1074
static bool column_in_column_list(int attnum, Bitmapset *columns)
Definition: proto.c:50
static void logicalrep_write_tuple(StringInfo out, Relation rel, TupleTableSlot *slot, bool binary, Bitmapset *columns)
Definition: proto.c:768
char * logicalrep_read_origin(StringInfo in, XLogRecPtr *origin_lsn)
Definition: proto.c:401
TransactionId logicalrep_read_stream_commit(StringInfo in, LogicalRepCommitData *commit_data)
Definition: proto.c:1142
LogicalRepRelId logicalrep_read_insert(StringInfo in, LogicalRepTupleData *newtup)
Definition: proto.c:436
void logicalrep_read_prepare(StringInfo in, LogicalRepPreparedTxnData *prepare_data)
Definition: proto.c:239
static const char * logicalrep_read_namespace(StringInfo in)
Definition: proto.c:1060
void logicalrep_write_stream_stop(StringInfo out)
Definition: proto.c:1108
TransactionId logicalrep_read_stream_start(StringInfo in, bool *first_segment)
Definition: proto.c:1092
#define RelationGetRelid(relation)
Definition: rel.h:489
#define RelationGetDescr(relation)
Definition: rel.h:515
#define RelationGetRelationName(relation)
Definition: rel.h:523
#define RelationGetNamespace(relation)
Definition: rel.h:530
Bitmapset * RelationGetIdentityKeyBitmap(Relation relation)
Definition: relcache.c:5355
#define rbtxn_prepared(txn)
Definition: pg_list.h:51
XLogRecPtr final_lsn
Definition: logicalproto.h:124
TransactionId xid
Definition: logicalproto.h:126
TimestampTz committime
Definition: logicalproto.h:125
TimestampTz committime
Definition: logicalproto.h:133
LogicalRepRelId remoteid
Definition: logicalproto.h:102
Bitmapset * attkeys
Definition: logicalproto.h:110
StringInfoData * colvalues
Definition: logicalproto.h:82
Form_pg_class rd_rel
Definition: rel.h:109
TimestampTz commit_time
XLogRecPtr final_lsn
XLogRecPtr end_lsn
TimestampTz prepare_time
TransactionId xid
union ReorderBufferTXN::@111 xact_time
bool * tts_isnull
Definition: tuptable.h:128
Datum * tts_values
Definition: tuptable.h:126
Definition: c.h:622
#define FirstLowInvalidHeapAttributeNumber
Definition: sysattr.h:27
void ReleaseSysCache(HeapTuple tuple)
Definition: syscache.c:1221
HeapTuple SearchSysCache1(int cacheId, Datum key1)
Definition: syscache.c:1173
@ TYPEOID
Definition: syscache.h:114
#define InvalidTransactionId
Definition: transam.h:31
#define TransactionIdIsValid(xid)
Definition: transam.h:41
#define TupleDescAttr(tupdesc, i)
Definition: tupdesc.h:92
static void slot_getallattrs(TupleTableSlot *slot)
Definition: tuptable.h:354
uint64 XLogRecPtr
Definition: xlogdefs.h:21
#define InvalidXLogRecPtr
Definition: xlogdefs.h:28