@ -7,7 +7,7 @@
* Copyright ( c ) 1996 - 2005 , PostgreSQL Global Development Group
*
* IDENTIFICATION
* $ PostgreSQL : pgsql / src / backend / commands / comment . c , v 1.85 2005 / 11 / 22 18 : 17 : 08 momjian Exp $
* $ PostgreSQL : pgsql / src / backend / commands / comment . c , v 1.86 2006 / 02 / 12 03 : 22 : 17 momjian Exp $
*
* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
*/
@ -18,6 +18,7 @@
# include "access/heapam.h"
# include "catalog/indexing.h"
# include "catalog/namespace.h"
# include "catalog/pg_authid.h"
# include "catalog/pg_cast.h"
# include "catalog/pg_constraint.h"
# include "catalog/pg_conversion.h"
@ -30,10 +31,13 @@
# include "catalog/pg_operator.h"
# include "catalog/pg_proc.h"
# include "catalog/pg_rewrite.h"
# include "catalog/pg_shdescription.h"
# include "catalog/pg_tablespace.h"
# include "catalog/pg_trigger.h"
# include "catalog/pg_type.h"
# include "commands/comment.h"
# include "commands/dbcommands.h"
# include "commands/tablespace.h"
# include "miscadmin.h"
# include "parser/parse_func.h"
# include "parser/parse_oper.h"
@ -70,6 +74,8 @@ static void CommentLanguage(List *qualname, char *comment);
static void CommentOpClass ( List * qualname , List * arguments , char * comment ) ;
static void CommentLargeObject ( List * qualname , char * comment ) ;
static void CommentCast ( List * qualname , List * arguments , char * comment ) ;
static void CommentTablespace ( List * qualname , char * comment ) ;
static void CommentRole ( List * qualname , char * comment ) ;
/*
@ -134,6 +140,12 @@ CommentObject(CommentStmt *stmt)
case OBJECT_CAST :
CommentCast ( stmt - > objname , stmt - > objargs , stmt - > comment ) ;
break ;
case OBJECT_TABLESPACE :
CommentTablespace ( stmt - > objname , stmt - > comment ) ;
break ;
case OBJECT_ROLE :
CommentRole ( stmt - > objname , stmt - > comment ) ;
break ;
default :
elog ( ERROR , " unrecognized object type: %d " ,
( int ) stmt - > objtype ) ;
@ -240,6 +252,100 @@ CreateComments(Oid oid, Oid classoid, int32 subid, char *comment)
heap_close ( description , NoLock ) ;
}
/*
* CreateSharedComments - -
*
* Create a comment for the specified shared object descriptor . Inserts a
* new pg_shdescription tuple , or replaces an existing one with the same key .
*
* If the comment given is null or an empty string , instead delete any
* existing comment for the specified key .
*/
void CreateSharedComments ( Oid oid , Oid classoid , char * comment )
{
Relation shdescription ;
ScanKeyData skey [ 2 ] ;
SysScanDesc sd ;
HeapTuple oldtuple ;
HeapTuple newtuple = NULL ;
Datum values [ Natts_pg_shdescription ] ;
char nulls [ Natts_pg_shdescription ] ;
char replaces [ Natts_pg_shdescription ] ;
int i ;
/* Reduce empty-string to NULL case */
if ( comment ! = NULL & & strlen ( comment ) = = 0 )
comment = NULL ;
/* Prepare to form or update a tuple, if necessary */
if ( comment ! = NULL )
{
for ( i = 0 ; i < Natts_pg_shdescription ; i + + )
{
nulls [ i ] = ' ' ;
replaces [ i ] = ' r ' ;
}
i = 0 ;
values [ i + + ] = ObjectIdGetDatum ( oid ) ;
values [ i + + ] = ObjectIdGetDatum ( classoid ) ;
values [ i + + ] = DirectFunctionCall1 ( textin , CStringGetDatum ( comment ) ) ;
}
/* Use the index to search for a matching old tuple */
ScanKeyInit ( & skey [ 0 ] ,
Anum_pg_shdescription_objoid ,
BTEqualStrategyNumber , F_OIDEQ ,
ObjectIdGetDatum ( oid ) ) ;
ScanKeyInit ( & skey [ 1 ] ,
Anum_pg_shdescription_classoid ,
BTEqualStrategyNumber , F_OIDEQ ,
ObjectIdGetDatum ( classoid ) ) ;
shdescription = heap_open ( SharedDescriptionRelationId , RowExclusiveLock ) ;
sd = systable_beginscan ( shdescription , SharedDescriptionObjIndexId , true ,
SnapshotNow , 2 , skey ) ;
while ( ( oldtuple = systable_getnext ( sd ) ) ! = NULL )
{
/* Found the old tuple, so delete or update it */
if ( comment = = NULL )
simple_heap_delete ( shdescription , & oldtuple - > t_self ) ;
else
{
newtuple = heap_modifytuple ( oldtuple , RelationGetDescr ( shdescription ) ,
values , nulls , replaces ) ;
simple_heap_update ( shdescription , & oldtuple - > t_self , newtuple ) ;
}
break ; /* Assume there can be only one match */
}
systable_endscan ( sd ) ;
/* If we didn't find an old tuple, insert a new one */
if ( newtuple = = NULL & & comment ! = NULL )
{
newtuple = heap_formtuple ( RelationGetDescr ( shdescription ) ,
values , nulls ) ;
simple_heap_insert ( shdescription , newtuple ) ;
}
/* Update indexes, if necessary */
if ( newtuple ! = NULL )
{
CatalogUpdateIndexes ( shdescription , newtuple ) ;
heap_freetuple ( newtuple ) ;
}
/* Done */
heap_close ( shdescription , NoLock ) ;
}
/*
* DeleteComments - - remove comments for an object
*
@ -292,6 +398,42 @@ DeleteComments(Oid oid, Oid classoid, int32 subid)
heap_close ( description , RowExclusiveLock ) ;
}
/*
* DeleteSharedComments - - remove comments for a shared object
*/
void
DeleteSharedComments ( Oid oid , Oid classoid )
{
Relation shdescription ;
ScanKeyData skey [ 2 ] ;
SysScanDesc sd ;
HeapTuple oldtuple ;
/* Use the index to search for all matching old tuples */
ScanKeyInit ( & skey [ 0 ] ,
Anum_pg_shdescription_objoid ,
BTEqualStrategyNumber , F_OIDEQ ,
ObjectIdGetDatum ( oid ) ) ;
ScanKeyInit ( & skey [ 1 ] ,
Anum_pg_shdescription_classoid ,
BTEqualStrategyNumber , F_OIDEQ ,
ObjectIdGetDatum ( classoid ) ) ;
shdescription = heap_open ( SharedDescriptionRelationId , RowExclusiveLock ) ;
sd = systable_beginscan ( shdescription , SharedDescriptionObjIndexId , true ,
SnapshotNow , 2 , skey ) ;
while ( ( oldtuple = systable_getnext ( sd ) ) ! = NULL )
simple_heap_delete ( shdescription , & oldtuple - > t_self ) ;
/* Done */
systable_endscan ( sd ) ;
heap_close ( shdescription , RowExclusiveLock ) ;
}
/*
* CommentRelation - -
*
@ -425,7 +567,7 @@ CommentAttribute(List *qualname, char *comment)
* have regarding the specified database . The routine will check
* security for owner permissions , and , if successful , will then
* attempt to find the oid of the database specified . Once found ,
* a comment is added / dropped using the CreateComments ( ) routine .
* a comment is added / dropped using the CreateShared Comments ( ) routine .
*/
static void
CommentDatabase ( List * qualname , char * comment )
@ -440,11 +582,6 @@ CommentDatabase(List *qualname, char *comment)
database = strVal ( linitial ( qualname ) ) ;
/*
* We cannot currently support cross - database comments ( since other DBs
* cannot see pg_description of this database ) . So , we reject attempts to
* comment on a database other than the current one . Someday this might be
* improved , but it would take a redesigned infrastructure .
*
* When loading a dump , we may see a COMMENT ON DATABASE for the old name
* of the database . Erroring out would prevent pg_restore from completing
* ( which is really pg_restore ' s fault , but for now we will work around
@ -462,23 +599,83 @@ CommentDatabase(List *qualname, char *comment)
return ;
}
/* Only allow comments on the current database */
if ( oid ! = MyDatabaseId )
/* Check object security */
if ( ! pg_database_ownercheck ( oid , GetUserId ( ) ) )
aclcheck_error ( ACLCHECK_NOT_OWNER , ACL_KIND_DATABASE ,
database ) ;
/* Call CreateSharedComments() to create/drop the comments */
CreateSharedComments ( oid , DatabaseRelationId , comment ) ;
}
/*
* CommentTablespace - -
*
* This routine is used to add / drop any user - comments a user might
* have regarding a tablespace . The tablepace is specified by name
* and , if found , and the user has appropriate permissions , a
* comment will be added / dropped using the CreateSharedComments ( ) routine .
*
*/
static void
CommentTablespace ( List * qualname , char * comment )
{
char * tablespace ;
Oid oid ;
if ( list_length ( qualname ) ! = 1 )
ereport ( ERROR ,
( errcode ( ERRCODE_SYNTAX_ERROR ) ,
errmsg ( " tablespace name may not be qualified " ) ) ) ;
tablespace = strVal ( linitial ( qualname ) ) ;
oid = get_tablespace_oid ( tablespace ) ;
if ( ! OidIsValid ( oid ) )
{
ereport ( WARNING , /* throw just a warning so pg_restore doesn't
* fail */
( errcode ( ERRCODE_FEATURE_NOT_SUPPORTED ) ,
errmsg ( " database comments may only be applied to the current database " ) ) ) ;
ereport ( ERROR ,
( errcode ( ERRCODE_UNDEFINED_OBJECT ) ,
errmsg ( " tablespace \" %s \" does not exist " , tablespace ) ) ) ;
return ;
}
/* Check object security */
if ( ! pg_database_ownercheck ( oid , GetUserId ( ) ) )
aclcheck_error ( ACLCHECK_NOT_OWNER , ACL_KIND_DATABASE ,
database ) ;
if ( ! pg_tablespace_ownercheck ( oid , GetUserId ( ) ) )
aclcheck_error ( ACLCHECK_NOT_OWNER , ACL_KIND_TABLESPACE , tablespace ) ;
/* Call CreateComments() to create/drop the comments */
CreateComments ( oid , DatabaseRelationId , 0 , comment ) ;
/* Call CreateSharedComments() to create/drop the comments */
CreateSharedComments ( oid , TableSpaceRelationId , comment ) ;
}
/*
* CommentRole - -
*
* This routine is used to add / drop any user - comments a user might
* have regarding a role . The role is specified by name
* and , if found , and the user has appropriate permissions , a
* comment will be added / dropped using the CreateSharedComments ( ) routine .
*/
static void
CommentRole ( List * qualname , char * comment )
{
char * role ;
Oid oid ;
if ( list_length ( qualname ) ! = 1 )
ereport ( ERROR ,
( errcode ( ERRCODE_SYNTAX_ERROR ) ,
errmsg ( " role name may not be qualified " ) ) ) ;
role = strVal ( linitial ( qualname ) ) ;
oid = get_roleid_checked ( role ) ;
/* Check object security */
if ( ! has_privs_of_role ( GetUserId ( ) , oid ) )
ereport ( ERROR ,
( errcode ( ERRCODE_INSUFFICIENT_PRIVILEGE ) ,
errmsg ( " must be member of role \" %s \" to comment upon it " , role ) ) ) ;
/* Call CreateSharedComments() to create/drop the comments */
CreateSharedComments ( oid , AuthIdRelationId , comment ) ;
}
/*
Bruce Momjian
20 years ago