Line data    Source code

       1             : /*-------------------------------------------------------------------------
       2             :  *
       3             :  * pg_parameter_acl.c
       4             :  *    routines to support manipulation of the pg_parameter_acl relation
       5             :  *
       6             :  * Portions Copyright (c) 1996-2023, 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"
      20             : #include "catalog/objectaccess.h"
      21             : #include "catalog/pg_namespace.h"
      22             : #include "catalog/pg_parameter_acl.h"
      23             : #include "utils/builtins.h"
      24             : #include "utils/guc.h"
      25             : #include "utils/pg_locale.h"
      26             : #include "utils/rel.h"
      27             : #include "utils/syscache.h"
      28             : 
      29             : 
      30             : /*
      31             :  * ParameterAclLookup - Given a configuration parameter name,
      32             :  * look up the associated configuration parameter ACL's OID.
      33             :  *
      34             :  * If missing_ok is false, throw an error if ACL entry not found.  If
      35             :  * true, just return InvalidOid.
      36             :  */
      37             : Oid
      38         128 : ParameterAclLookup(const char *parameter, bool missing_ok)
      39             : {
      40             :     Oid         oid;
      41             :     char       *parname;
      42             : 
      43             :     /* Convert name to the form it should have in pg_parameter_acl... */
      44         128 :     parname = convert_GUC_name_for_parameter_acl(parameter);
      45             : 
      46             :     /* ... and look it up */
      47         128 :     oid = GetSysCacheOid1(PARAMETERACLNAME, Anum_pg_parameter_acl_oid,
      48             :                           PointerGetDatum(cstring_to_text(parname)));
      49             : 
      50         128 :     if (!OidIsValid(oid) && !missing_ok)
      51           0 :         ereport(ERROR,
      52             :                 (errcode(ERRCODE_UNDEFINED_OBJECT),
      53             :                  errmsg("parameter ACL \"%s\" does not exist", parameter)));
      54             : 
      55         128 :     pfree(parname);
      56             : 
      57         128 :     return oid;
      58             : }
      59             : 
      60             : /*
      61             :  * ParameterAclCreate
      62             :  *
      63             :  * Add a new tuple to pg_parameter_acl.
      64             :  *
      65             :  * parameter: the parameter name to create an entry for.
      66             :  * Caller should have verified that there's no such entry already.
      67             :  *
      68             :  * Returns the new entry's OID.
      69             :  */
      70             : Oid
      71          68 : ParameterAclCreate(const char *parameter)
      72             : {
      73             :     Oid         parameterId;
      74             :     char       *parname;
      75             :     Relation    rel;
      76             :     TupleDesc   tupDesc;
      77             :     HeapTuple   tuple;
      78          68 :     Datum       values[Natts_pg_parameter_acl] = {0};
      79          68 :     bool        nulls[Natts_pg_parameter_acl] = {0};
      80             : 
      81             :     /*
      82             :      * To prevent cluttering pg_parameter_acl with useless entries, insist
      83             :      * that the name be valid.
      84             :      */
      85          68 :     check_GUC_name_for_parameter_acl(parameter);
      86             : 
      87             :     /* Convert name to the form it should have in pg_parameter_acl. */
      88          66 :     parname = convert_GUC_name_for_parameter_acl(parameter);
      89             : 
      90             :     /*
      91             :      * Create and insert a new record containing a null ACL.
      92             :      *
      93             :      * We don't take a strong enough lock to prevent concurrent insertions,
      94             :      * relying instead on the unique index.
      95             :      */
      96          66 :     rel = table_open(ParameterAclRelationId, RowExclusiveLock);
      97          66 :     tupDesc = RelationGetDescr(rel);
      98          66 :     parameterId = GetNewOidWithIndex(rel,
      99             :                                      ParameterAclOidIndexId,
     100             :                                      Anum_pg_parameter_acl_oid);
     101          66 :     values[Anum_pg_parameter_acl_oid - 1] = ObjectIdGetDatum(parameterId);
     102          66 :     values[Anum_pg_parameter_acl_parname - 1] =
     103          66 :         PointerGetDatum(cstring_to_text(parname));
     104          66 :     nulls[Anum_pg_parameter_acl_paracl - 1] = true;
     105          66 :     tuple = heap_form_tuple(tupDesc, values, nulls);
     106          66 :     CatalogTupleInsert(rel, tuple);
     107             : 
     108             :     /* Close pg_parameter_acl, but keep lock till commit. */
     109          66 :     heap_freetuple(tuple);
     110          66 :     table_close(rel, NoLock);
     111             : 
     112          66 :     return parameterId;
     113             : }