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pg_parameter_acl.c
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1 /*-------------------------------------------------------------------------
2  *
3  * pg_parameter_acl.c
4  * routines to support manipulation of the pg_parameter_acl relation
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/catalog/pg_parameter_acl.c
12  *
13  *-------------------------------------------------------------------------
14  */
15 #include "postgres.h"
16 
17 #include "access/table.h"
18 #include "catalog/catalog.h"
19 #include "catalog/indexing.h"
21 #include "utils/builtins.h"
22 #include "utils/guc.h"
23 #include "utils/rel.h"
24 #include "utils/syscache.h"
25 
26 
27 /*
28  * ParameterAclLookup - Given a configuration parameter name,
29  * look up the associated configuration parameter ACL's OID.
30  *
31  * If missing_ok is false, throw an error if ACL entry not found. If
32  * true, just return InvalidOid.
33  */
34 Oid
35 ParameterAclLookup(const char *parameter, bool missing_ok)
36 {
37  Oid oid;
38  char *parname;
39 
40  /* Convert name to the form it should have in pg_parameter_acl... */
41  parname = convert_GUC_name_for_parameter_acl(parameter);
42 
43  /* ... and look it up */
44  oid = GetSysCacheOid1(PARAMETERACLNAME, Anum_pg_parameter_acl_oid,
46 
47  if (!OidIsValid(oid) && !missing_ok)
48  ereport(ERROR,
49  (errcode(ERRCODE_UNDEFINED_OBJECT),
50  errmsg("parameter ACL \"%s\" does not exist", parameter)));
51 
52  pfree(parname);
53 
54  return oid;
55 }
56 
57 /*
58  * ParameterAclCreate
59  *
60  * Add a new tuple to pg_parameter_acl.
61  *
62  * parameter: the parameter name to create an entry for.
63  * Caller should have verified that there's no such entry already.
64  *
65  * Returns the new entry's OID.
66  */
67 Oid
68 ParameterAclCreate(const char *parameter)
69 {
70  Oid parameterId;
71  char *parname;
72  Relation rel;
73  TupleDesc tupDesc;
74  HeapTuple tuple;
75  Datum values[Natts_pg_parameter_acl] = {0};
76  bool nulls[Natts_pg_parameter_acl] = {0};
77 
78  /*
79  * To prevent cluttering pg_parameter_acl with useless entries, insist
80  * that the name be valid.
81  */
83 
84  /* Convert name to the form it should have in pg_parameter_acl. */
85  parname = convert_GUC_name_for_parameter_acl(parameter);
86 
87  /*
88  * Create and insert a new record containing a null ACL.
89  *
90  * We don't take a strong enough lock to prevent concurrent insertions,
91  * relying instead on the unique index.
92  */
93  rel = table_open(ParameterAclRelationId, RowExclusiveLock);
94  tupDesc = RelationGetDescr(rel);
95  parameterId = GetNewOidWithIndex(rel,
96  ParameterAclOidIndexId,
97  Anum_pg_parameter_acl_oid);
98  values[Anum_pg_parameter_acl_oid - 1] = ObjectIdGetDatum(parameterId);
99  values[Anum_pg_parameter_acl_parname - 1] =
101  nulls[Anum_pg_parameter_acl_paracl - 1] = true;
102  tuple = heap_form_tuple(tupDesc, values, nulls);
103  CatalogTupleInsert(rel, tuple);
104 
105  /* Close pg_parameter_acl, but keep lock till commit. */
106  heap_freetuple(tuple);
107  table_close(rel, NoLock);
108 
109  return parameterId;
110 }
static Datum values[MAXATTR]
Definition: bootstrap.c:152
#define OidIsValid(objectId)
Definition: c.h:775
Oid GetNewOidWithIndex(Relation relation, Oid indexId, AttrNumber oidcolumn)
Definition: catalog.c:391
int errcode(int sqlerrcode)
Definition: elog.c:857
int errmsg(const char *fmt,...)
Definition: elog.c:1070
#define ERROR
Definition: elog.h:39
#define ereport(elevel,...)
Definition: elog.h:149
void check_GUC_name_for_parameter_acl(const char *name)
Definition: guc.c:1412
char * convert_GUC_name_for_parameter_acl(const char *name)
Definition: guc.c:1376
HeapTuple heap_form_tuple(TupleDesc tupleDescriptor, const Datum *values, const bool *isnull)
Definition: heaptuple.c:1116
void heap_freetuple(HeapTuple htup)
Definition: heaptuple.c:1434
void CatalogTupleInsert(Relation heapRel, HeapTuple tup)
Definition: indexing.c:233
#define NoLock
Definition: lockdefs.h:34
#define RowExclusiveLock
Definition: lockdefs.h:38
void pfree(void *pointer)
Definition: mcxt.c:1520
Oid ParameterAclLookup(const char *parameter, bool missing_ok)
Oid ParameterAclCreate(const char *parameter)
static Datum PointerGetDatum(const void *X)
Definition: postgres.h:322
uintptr_t Datum
Definition: postgres.h:64
static Datum ObjectIdGetDatum(Oid X)
Definition: postgres.h:252
unsigned int Oid
Definition: postgres_ext.h:31
#define RelationGetDescr(relation)
Definition: rel.h:531
#define GetSysCacheOid1(cacheId, oidcol, key1)
Definition: syscache.h:104
void table_close(Relation relation, LOCKMODE lockmode)
Definition: table.c:126
Relation table_open(Oid relationId, LOCKMODE lockmode)
Definition: table.c:40
text * cstring_to_text(const char *s)
Definition: varlena.c:184