*** a/doc/src/sgml/func.sgml
--- b/doc/src/sgml/func.sgml
***************
*** 12349,12357 **** SET search_path TO <replaceable>schema</> <optional>, <replaceable>schema</>, ..
     <para>
      <function>has_table_privilege</function> checks whether a user
      can access a table in a particular way.  The user can be
!     specified by name or by OID
!     (<literal>pg_authid.oid</literal>), or if the argument is
!     omitted
      <function>current_user</function> is assumed.  The table can be specified
      by name or by OID.  (Thus, there are actually six variants of
      <function>has_table_privilege</function>, which can be distinguished by
--- 12349,12357 ----
     <para>
      <function>has_table_privilege</function> checks whether a user
      can access a table in a particular way.  The user can be
!     specified by name; as <literal>public</>, to indicate the PUBLIC pseudo-role; by OID
!     (<literal>pg_authid.oid</literal>), or, if the argument is
!     omitted,
      <function>current_user</function> is assumed.  The table can be specified
      by name or by OID.  (Thus, there are actually six variants of
      <function>has_table_privilege</function>, which can be distinguished by
***************
*** 12497,12503 **** SELECT has_function_privilege('joeuser', 'myfunc(int, text)', 'execute');
      <function>pg_has_role</function> checks whether a user
      can access a role in a particular way.
      Its argument possibilities
!     are analogous to <function>has_table_privilege</function>.
      The desired access privilege type must evaluate to some combination of
      <literal>MEMBER</literal> or
      <literal>USAGE</literal>.
--- 12497,12504 ----
      <function>pg_has_role</function> checks whether a user
      can access a role in a particular way.
      Its argument possibilities
!     are analogous to <function>has_table_privilege</function>,
!     except that <literal>public</> is not allowed as user name.
      The desired access privilege type must evaluate to some combination of
      <literal>MEMBER</literal> or
      <literal>USAGE</literal>.
*** a/src/backend/utils/adt/acl.c
--- b/src/backend/utils/adt/acl.c
***************
*** 113,118 **** static AclMode convert_role_priv_string(text *priv_type_text);
--- 113,119 ----
  static AclResult pg_role_aclcheck(Oid role_oid, Oid roleid, AclMode mode);
  
  static void RoleMembershipCacheCallback(Datum arg, int cacheid, ItemPointer tuplePtr);
+ static Oid get_role_oid_or_public(const char *rolname);
  
  
  /*
***************
*** 1791,1797 **** has_table_privilege_name_name(PG_FUNCTION_ARGS)
  	AclMode		mode;
  	AclResult	aclresult;
  
! 	roleid = get_role_oid(NameStr(*rolename), false);
  	tableoid = convert_table_name(tablename);
  	mode = convert_table_priv_string(priv_type_text);
  
--- 1792,1798 ----
  	AclMode		mode;
  	AclResult	aclresult;
  
! 	roleid = get_role_oid_or_public(NameStr(*rolename));
  	tableoid = convert_table_name(tablename);
  	mode = convert_table_priv_string(priv_type_text);
  
***************
*** 1840,1846 **** has_table_privilege_name_id(PG_FUNCTION_ARGS)
  	AclMode		mode;
  	AclResult	aclresult;
  
! 	roleid = get_role_oid(NameStr(*username), false);
  	mode = convert_table_priv_string(priv_type_text);
  
  	if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(tableoid)))
--- 1841,1847 ----
  	AclMode		mode;
  	AclResult	aclresult;
  
! 	roleid = get_role_oid_or_public(NameStr(*username));
  	mode = convert_table_priv_string(priv_type_text);
  
  	if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(tableoid)))
***************
*** 1998,2004 **** has_sequence_privilege_name_name(PG_FUNCTION_ARGS)
  	AclMode		mode;
  	AclResult	aclresult;
  
! 	roleid = get_role_oid(NameStr(*rolename), false);
  	mode = convert_sequence_priv_string(priv_type_text);
  	sequenceoid = convert_table_name(sequencename);
  	if (get_rel_relkind(sequenceoid) != RELKIND_SEQUENCE)
--- 1999,2005 ----
  	AclMode		mode;
  	AclResult	aclresult;
  
! 	roleid = get_role_oid_or_public(NameStr(*rolename));
  	mode = convert_sequence_priv_string(priv_type_text);
  	sequenceoid = convert_table_name(sequencename);
  	if (get_rel_relkind(sequenceoid) != RELKIND_SEQUENCE)
***************
*** 2058,2064 **** has_sequence_privilege_name_id(PG_FUNCTION_ARGS)
  	AclResult	aclresult;
  	char		relkind;
  
! 	roleid = get_role_oid(NameStr(*username), false);
  	mode = convert_sequence_priv_string(priv_type_text);
  	relkind = get_rel_relkind(sequenceoid);
  	if (relkind == '\0')
--- 2059,2065 ----
  	AclResult	aclresult;
  	char		relkind;
  
! 	roleid = get_role_oid_or_public(NameStr(*username));
  	mode = convert_sequence_priv_string(priv_type_text);
  	relkind = get_rel_relkind(sequenceoid);
  	if (relkind == '\0')
***************
*** 2209,2215 **** has_any_column_privilege_name_name(PG_FUNCTION_ARGS)
  	AclMode		mode;
  	AclResult	aclresult;
  
! 	roleid = get_role_oid(NameStr(*rolename), false);
  	tableoid = convert_table_name(tablename);
  	mode = convert_column_priv_string(priv_type_text);
  
--- 2210,2216 ----
  	AclMode		mode;
  	AclResult	aclresult;
  
! 	roleid = get_role_oid_or_public(NameStr(*rolename));
  	tableoid = convert_table_name(tablename);
  	mode = convert_column_priv_string(priv_type_text);
  
***************
*** 2266,2272 **** has_any_column_privilege_name_id(PG_FUNCTION_ARGS)
  	AclMode		mode;
  	AclResult	aclresult;
  
! 	roleid = get_role_oid(NameStr(*username), false);
  	mode = convert_column_priv_string(priv_type_text);
  
  	if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(tableoid)))
--- 2267,2273 ----
  	AclMode		mode;
  	AclResult	aclresult;
  
! 	roleid = get_role_oid_or_public(NameStr(*username));
  	mode = convert_column_priv_string(priv_type_text);
  
  	if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(tableoid)))
***************
*** 2451,2457 **** has_column_privilege_name_name_name(PG_FUNCTION_ARGS)
  	AclMode		mode;
  	int			privresult;
  
! 	roleid = get_role_oid(NameStr(*rolename), false);
  	tableoid = convert_table_name(tablename);
  	colattnum = convert_column_name(tableoid, column);
  	mode = convert_column_priv_string(priv_type_text);
--- 2452,2458 ----
  	AclMode		mode;
  	int			privresult;
  
! 	roleid = get_role_oid_or_public(NameStr(*rolename));
  	tableoid = convert_table_name(tablename);
  	colattnum = convert_column_name(tableoid, column);
  	mode = convert_column_priv_string(priv_type_text);
***************
*** 2479,2485 **** has_column_privilege_name_name_attnum(PG_FUNCTION_ARGS)
  	AclMode		mode;
  	int			privresult;
  
! 	roleid = get_role_oid(NameStr(*rolename), false);
  	tableoid = convert_table_name(tablename);
  	mode = convert_column_priv_string(priv_type_text);
  
--- 2480,2486 ----
  	AclMode		mode;
  	int			privresult;
  
! 	roleid = get_role_oid_or_public(NameStr(*rolename));
  	tableoid = convert_table_name(tablename);
  	mode = convert_column_priv_string(priv_type_text);
  
***************
*** 2506,2512 **** has_column_privilege_name_id_name(PG_FUNCTION_ARGS)
  	AclMode		mode;
  	int			privresult;
  
! 	roleid = get_role_oid(NameStr(*username), false);
  	colattnum = convert_column_name(tableoid, column);
  	mode = convert_column_priv_string(priv_type_text);
  
--- 2507,2513 ----
  	AclMode		mode;
  	int			privresult;
  
! 	roleid = get_role_oid_or_public(NameStr(*username));
  	colattnum = convert_column_name(tableoid, column);
  	mode = convert_column_priv_string(priv_type_text);
  
***************
*** 2532,2538 **** has_column_privilege_name_id_attnum(PG_FUNCTION_ARGS)
  	AclMode		mode;
  	int			privresult;
  
! 	roleid = get_role_oid(NameStr(*username), false);
  	mode = convert_column_priv_string(priv_type_text);
  
  	privresult = column_privilege_check(tableoid, colattnum, roleid, mode);
--- 2533,2539 ----
  	AclMode		mode;
  	int			privresult;
  
! 	roleid = get_role_oid_or_public(NameStr(*username));
  	mode = convert_column_priv_string(priv_type_text);
  
  	privresult = column_privilege_check(tableoid, colattnum, roleid, mode);
***************
*** 2823,2829 **** has_database_privilege_name_name(PG_FUNCTION_ARGS)
  	AclMode		mode;
  	AclResult	aclresult;
  
! 	roleid = get_role_oid(NameStr(*username), false);
  	databaseoid = convert_database_name(databasename);
  	mode = convert_database_priv_string(priv_type_text);
  
--- 2824,2830 ----
  	AclMode		mode;
  	AclResult	aclresult;
  
! 	roleid = get_role_oid_or_public(NameStr(*username));
  	databaseoid = convert_database_name(databasename);
  	mode = convert_database_priv_string(priv_type_text);
  
***************
*** 2872,2878 **** has_database_privilege_name_id(PG_FUNCTION_ARGS)
  	AclMode		mode;
  	AclResult	aclresult;
  
! 	roleid = get_role_oid(NameStr(*username), false);
  	mode = convert_database_priv_string(priv_type_text);
  
  	if (!SearchSysCacheExists1(DATABASEOID, ObjectIdGetDatum(databaseoid)))
--- 2873,2879 ----
  	AclMode		mode;
  	AclResult	aclresult;
  
! 	roleid = get_role_oid_or_public(NameStr(*username));
  	mode = convert_database_priv_string(priv_type_text);
  
  	if (!SearchSysCacheExists1(DATABASEOID, ObjectIdGetDatum(databaseoid)))
***************
*** 3021,3027 **** has_foreign_data_wrapper_privilege_name_name(PG_FUNCTION_ARGS)
  	AclMode		mode;
  	AclResult	aclresult;
  
! 	roleid = get_role_oid(NameStr(*username), false);
  	fdwid = convert_foreign_data_wrapper_name(fdwname);
  	mode = convert_foreign_data_wrapper_priv_string(priv_type_text);
  
--- 3022,3028 ----
  	AclMode		mode;
  	AclResult	aclresult;
  
! 	roleid = get_role_oid_or_public(NameStr(*username));
  	fdwid = convert_foreign_data_wrapper_name(fdwname);
  	mode = convert_foreign_data_wrapper_priv_string(priv_type_text);
  
***************
*** 3070,3076 **** has_foreign_data_wrapper_privilege_name_id(PG_FUNCTION_ARGS)
  	AclMode		mode;
  	AclResult	aclresult;
  
! 	roleid = get_role_oid(NameStr(*username), false);
  	mode = convert_foreign_data_wrapper_priv_string(priv_type_text);
  
  	aclresult = pg_foreign_data_wrapper_aclcheck(fdwid, roleid, mode);
--- 3071,3077 ----
  	AclMode		mode;
  	AclResult	aclresult;
  
! 	roleid = get_role_oid_or_public(NameStr(*username));
  	mode = convert_foreign_data_wrapper_priv_string(priv_type_text);
  
  	aclresult = pg_foreign_data_wrapper_aclcheck(fdwid, roleid, mode);
***************
*** 3203,3209 **** has_function_privilege_name_name(PG_FUNCTION_ARGS)
  	AclMode		mode;
  	AclResult	aclresult;
  
! 	roleid = get_role_oid(NameStr(*username), false);
  	functionoid = convert_function_name(functionname);
  	mode = convert_function_priv_string(priv_type_text);
  
--- 3204,3210 ----
  	AclMode		mode;
  	AclResult	aclresult;
  
! 	roleid = get_role_oid_or_public(NameStr(*username));
  	functionoid = convert_function_name(functionname);
  	mode = convert_function_priv_string(priv_type_text);
  
***************
*** 3252,3258 **** has_function_privilege_name_id(PG_FUNCTION_ARGS)
  	AclMode		mode;
  	AclResult	aclresult;
  
! 	roleid = get_role_oid(NameStr(*username), false);
  	mode = convert_function_priv_string(priv_type_text);
  
  	if (!SearchSysCacheExists1(PROCOID, ObjectIdGetDatum(functionoid)))
--- 3253,3259 ----
  	AclMode		mode;
  	AclResult	aclresult;
  
! 	roleid = get_role_oid_or_public(NameStr(*username));
  	mode = convert_function_priv_string(priv_type_text);
  
  	if (!SearchSysCacheExists1(PROCOID, ObjectIdGetDatum(functionoid)))
***************
*** 3403,3409 **** has_language_privilege_name_name(PG_FUNCTION_ARGS)
  	AclMode		mode;
  	AclResult	aclresult;
  
! 	roleid = get_role_oid(NameStr(*username), false);
  	languageoid = convert_language_name(languagename);
  	mode = convert_language_priv_string(priv_type_text);
  
--- 3404,3410 ----
  	AclMode		mode;
  	AclResult	aclresult;
  
! 	roleid = get_role_oid_or_public(NameStr(*username));
  	languageoid = convert_language_name(languagename);
  	mode = convert_language_priv_string(priv_type_text);
  
***************
*** 3452,3458 **** has_language_privilege_name_id(PG_FUNCTION_ARGS)
  	AclMode		mode;
  	AclResult	aclresult;
  
! 	roleid = get_role_oid(NameStr(*username), false);
  	mode = convert_language_priv_string(priv_type_text);
  
  	if (!SearchSysCacheExists1(LANGOID, ObjectIdGetDatum(languageoid)))
--- 3453,3459 ----
  	AclMode		mode;
  	AclResult	aclresult;
  
! 	roleid = get_role_oid_or_public(NameStr(*username));
  	mode = convert_language_priv_string(priv_type_text);
  
  	if (!SearchSysCacheExists1(LANGOID, ObjectIdGetDatum(languageoid)))
***************
*** 3594,3600 **** has_schema_privilege_name_name(PG_FUNCTION_ARGS)
  	AclMode		mode;
  	AclResult	aclresult;
  
! 	roleid = get_role_oid(NameStr(*username), false);
  	schemaoid = convert_schema_name(schemaname);
  	mode = convert_schema_priv_string(priv_type_text);
  
--- 3595,3601 ----
  	AclMode		mode;
  	AclResult	aclresult;
  
! 	roleid = get_role_oid_or_public(NameStr(*username));
  	schemaoid = convert_schema_name(schemaname);
  	mode = convert_schema_priv_string(priv_type_text);
  
***************
*** 3643,3649 **** has_schema_privilege_name_id(PG_FUNCTION_ARGS)
  	AclMode		mode;
  	AclResult	aclresult;
  
! 	roleid = get_role_oid(NameStr(*username), false);
  	mode = convert_schema_priv_string(priv_type_text);
  
  	if (!SearchSysCacheExists1(NAMESPACEOID, ObjectIdGetDatum(schemaoid)))
--- 3644,3650 ----
  	AclMode		mode;
  	AclResult	aclresult;
  
! 	roleid = get_role_oid_or_public(NameStr(*username));
  	mode = convert_schema_priv_string(priv_type_text);
  
  	if (!SearchSysCacheExists1(NAMESPACEOID, ObjectIdGetDatum(schemaoid)))
***************
*** 3787,3793 **** has_server_privilege_name_name(PG_FUNCTION_ARGS)
  	AclMode		mode;
  	AclResult	aclresult;
  
! 	roleid = get_role_oid(NameStr(*username), false);
  	serverid = convert_server_name(servername);
  	mode = convert_server_priv_string(priv_type_text);
  
--- 3788,3794 ----
  	AclMode		mode;
  	AclResult	aclresult;
  
! 	roleid = get_role_oid_or_public(NameStr(*username));
  	serverid = convert_server_name(servername);
  	mode = convert_server_priv_string(priv_type_text);
  
***************
*** 3836,3842 **** has_server_privilege_name_id(PG_FUNCTION_ARGS)
  	AclMode		mode;
  	AclResult	aclresult;
  
! 	roleid = get_role_oid(NameStr(*username), false);
  	mode = convert_server_priv_string(priv_type_text);
  
  	aclresult = pg_foreign_server_aclcheck(serverid, roleid, mode);
--- 3837,3843 ----
  	AclMode		mode;
  	AclResult	aclresult;
  
! 	roleid = get_role_oid_or_public(NameStr(*username));
  	mode = convert_server_priv_string(priv_type_text);
  
  	aclresult = pg_foreign_server_aclcheck(serverid, roleid, mode);
***************
*** 3969,3975 **** has_tablespace_privilege_name_name(PG_FUNCTION_ARGS)
  	AclMode		mode;
  	AclResult	aclresult;
  
! 	roleid = get_role_oid(NameStr(*username), false);
  	tablespaceoid = convert_tablespace_name(tablespacename);
  	mode = convert_tablespace_priv_string(priv_type_text);
  
--- 3970,3976 ----
  	AclMode		mode;
  	AclResult	aclresult;
  
! 	roleid = get_role_oid_or_public(NameStr(*username));
  	tablespaceoid = convert_tablespace_name(tablespacename);
  	mode = convert_tablespace_priv_string(priv_type_text);
  
***************
*** 4018,4024 **** has_tablespace_privilege_name_id(PG_FUNCTION_ARGS)
  	AclMode		mode;
  	AclResult	aclresult;
  
! 	roleid = get_role_oid(NameStr(*username), false);
  	mode = convert_tablespace_priv_string(priv_type_text);
  
  	aclresult = pg_tablespace_aclcheck(tablespaceoid, roleid, mode);
--- 4019,4025 ----
  	AclMode		mode;
  	AclResult	aclresult;
  
! 	roleid = get_role_oid_or_public(NameStr(*username));
  	mode = convert_tablespace_priv_string(priv_type_text);
  
  	aclresult = pg_tablespace_aclcheck(tablespaceoid, roleid, mode);
***************
*** 4821,4823 **** get_role_oid(const char *rolname, bool missing_ok)
--- 4822,4839 ----
  				 errmsg("role \"%s\" does not exist", rolname)));
  	return oid;
  }
+ 
+ /*
+  * get_role_oid_or_public - As above, but return ACL_ID_PUBLIC if the
+  * 		role name is "public".
+  */
+ static Oid
+ get_role_oid_or_public(const char *rolname)
+ {
+ 	Oid			oid;
+ 
+ 	if (strcmp(rolname, "public") == 0)
+ 		return ACL_ID_PUBLIC;
+ 
+ 	return get_role_oid(rolname, false);
+ }