src/backend/access/sequence/sequence.c

   1 /*-------------------------------------------------------------------------
   2  *
   3  * sequence.c
   4  *        Generic routines for sequence-related code.
   5  *
   6  * Portions Copyright (c) 1996-2024, PostgreSQL Global Development Group
   7  * Portions Copyright (c) 1994, Regents of the University of California
   8  *
   9  *
  10  * IDENTIFICATION
  11  *        src/backend/access/sequence/sequence.c
  12  *
  13  *
  14  * NOTES
  15  *        This file contains sequence_ routines that implement access to sequences
  16  *        (in contrast to other relation types like indexes).
  17  *
  18  *-------------------------------------------------------------------------
  19  */
  20
  21 #include "postgres.h"
  22
  23 #include "access/relation.h"
  24 #include "access/sequence.h"
  25 #include "storage/lmgr.h"
  26
  27 static inline void validate_relation_kind(Relation r);
  28
  29 /* ----------------
  30  *              sequence_open - open a sequence relation by relation OID
  31  *
  32  *              This is essentially relation_open plus check that the relation
  33  *              is a sequence.
  34  * ----------------
  35  */
  36 Relation
  37 sequence_open(Oid relationId, LOCKMODE lockmode)
  38 {
  39         Relation        r;
  40
  41         r = relation_open(relationId, lockmode);
  42
  43         validate_relation_kind(r);
  44
  45         return r;
  46 }
  47
  48 /* ----------------
  49  *              sequence_close - close a sequence
  50  *
  51  *              If lockmode is not "NoLock", we then release the specified lock.
  52  *
  53  *              Note that it is often sensible to hold a lock beyond relation_close;
  54  *              in that case, the lock is released automatically at xact end.
  55  * ----------------
  56  */
  57 void
  58 sequence_close(Relation relation, LOCKMODE lockmode)
  59 {
  60         relation_close(relation, lockmode);
  61 }
  62
  63 /* ----------------
  64  *              validate_relation_kind - check the relation's kind
  65  *
  66  *              Make sure relkind is from a sequence.
  67  * ----------------
  68  */
  69 static inline void
  70 validate_relation_kind(Relation r)
  71 {
  72         if (r->rd_rel->relkind != RELKIND_SEQUENCE)
  73                 ereport(ERROR,
  74                                 (errcode(ERRCODE_WRONG_OBJECT_TYPE),
  75                                  errmsg("cannot open relation \"%s\"",
  76                                                 RelationGetRelationName(r)),
  77                                  errdetail_relkind_not_supported(r->rd_rel->relkind)));
  78 }