/*
* Alter table space options
*/
Oid
AlterTableSpaceOptions(AlterTableSpaceOptionsStmt *stmt)
{
Relation rel;
ScanKeyData entry[1];
HeapScanDesc scandesc;
HeapTuple tup;
Oid tablespaceoid;
Datum datum;
Datum newOptions;
Datum repl_val[Natts_pg_tablespace];
bool isnull;
bool repl_null[Natts_pg_tablespace];
bool repl_repl[Natts_pg_tablespace];
HeapTuple newtuple;
/* Search pg_tablespace */
rel = heap_open(TableSpaceRelationId, RowExclusiveLock);
ScanKeyInit(&entry[0],
Anum_pg_tablespace_spcname,
BTEqualStrategyNumber, F_NAMEEQ,
CStringGetDatum(stmt->tablespacename));
scandesc = heap_beginscan_catalog(rel, 1, entry);
tup = heap_getnext(scandesc, ForwardScanDirection);
if (!HeapTupleIsValid(tup))
ereport(ERROR,
(errcode(ERRCODE_UNDEFINED_OBJECT),
errmsg("tablespace \"%s\" does not exist",
stmt->tablespacename)));
tablespaceoid = HeapTupleGetOid(tup);
/* Must be owner of the existing object */
if (!pg_tablespace_ownercheck(HeapTupleGetOid(tup), GetUserId()))
aclcheck_error(ACLCHECK_NOT_OWNER, ACL_KIND_TABLESPACE,
stmt->tablespacename);
/* Generate new proposed spcoptions (text array) */
datum = heap_getattr(tup, Anum_pg_tablespace_spcoptions,
RelationGetDescr(rel), &isnull);
newOptions = transformRelOptions(isnull ? (Datum) 0 : datum,
stmt->options, NULL, NULL, false,
stmt->isReset);
(void) tablespace_reloptions(newOptions, true);
/* Build new tuple. */
memset(repl_null, false, sizeof(repl_null));
memset(repl_repl, false, sizeof(repl_repl));
if (newOptions != (Datum) 0)
repl_val[Anum_pg_tablespace_spcoptions - 1] = newOptions;
else
repl_null[Anum_pg_tablespace_spcoptions - 1] = true;
repl_repl[Anum_pg_tablespace_spcoptions - 1] = true;
newtuple = heap_modify_tuple(tup, RelationGetDescr(rel), repl_val,
repl_null, repl_repl);
/* Update system catalog. */
simple_heap_update(rel, &newtuple->t_self, newtuple);
CatalogUpdateIndexes(rel, newtuple);
InvokeObjectPostAlterHook(TableSpaceRelationId, HeapTupleGetOid(tup), 0);
heap_freetuple(newtuple);
/* Conclude heap scan. */
heap_endscan(scandesc);
heap_close(rel, NoLock);
return tablespaceoid;
}
/*
* get_tablespace
* Fetch TableSpaceCacheEntry structure for a specified table OID.
*
* Pointers returned by this function should not be stored, since a cache
* flush will invalidate them.
*/
static TableSpaceCacheEntry *
get_tablespace(Oid spcid)
{
TableSpaceCacheEntry *spc;
HeapTuple tp;
TableSpaceOpts *opts;
/*
* Since spcid is always from a pg_class tuple, InvalidOid implies the
* default.
*/
if (spcid == InvalidOid)
spcid = MyDatabaseTableSpace;
/* Find existing cache entry, if any. */
if (!TableSpaceCacheHash)
InitializeTableSpaceCache();
spc = (TableSpaceCacheEntry *) hash_search(TableSpaceCacheHash,
(void *) &spcid,
HASH_FIND,
NULL);
if (spc)
return spc;
/*
* Not found in TableSpace cache. Check catcache. If we don't find a
* valid HeapTuple, it must mean someone has managed to request tablespace
* details for a non-existent tablespace. We'll just treat that case as
* if no options were specified.
*/
tp = SearchSysCache1(TABLESPACEOID, ObjectIdGetDatum(spcid));
if (!HeapTupleIsValid(tp))
opts = NULL;
else
{
Datum datum;
bool isNull;
datum = SysCacheGetAttr(TABLESPACEOID,
tp,
Anum_pg_tablespace_spcoptions,
&isNull);
if (isNull)
opts = NULL;
else
{
bytea *bytea_opts = tablespace_reloptions(datum, false);
opts = MemoryContextAlloc(CacheMemoryContext, VARSIZE(bytea_opts));
memcpy(opts, bytea_opts, VARSIZE(bytea_opts));
}
ReleaseSysCache(tp);
}
/*
* Now create the cache entry. It's important to do this only after
* reading the pg_tablespace entry, since doing so could cause a cache
* flush.
*/
spc = (TableSpaceCacheEntry *) hash_search(TableSpaceCacheHash,
(void *) &spcid,
HASH_ENTER,
NULL);
spc->opts = opts;
return spc;
}
/*
* Create a table space
*
* Only superusers can create a tablespace. This seems a reasonable restriction
* since we're determining the system layout and, anyway, we probably have
* root if we're doing this kind of activity
*/
Oid
CreateTableSpace(CreateTableSpaceStmt *stmt)
{
#ifdef HAVE_SYMLINK
Relation rel;
Datum values[Natts_pg_tablespace];
bool nulls[Natts_pg_tablespace];
HeapTuple tuple;
Oid tablespaceoid;
char *location;
Oid ownerId;
Datum newOptions;
/* Must be super user */
if (!superuser())
ereport(ERROR,
(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
errmsg("permission denied to create tablespace \"%s\"",
stmt->tablespacename),
errhint("Must be superuser to create a tablespace.")));
/* However, the eventual owner of the tablespace need not be */
if (stmt->owner)
ownerId = get_rolespec_oid(stmt->owner, false);
else
ownerId = GetUserId();
/* Unix-ify the offered path, and strip any trailing slashes */
location = pstrdup(stmt->location);
canonicalize_path(location);
/* disallow quotes, else CREATE DATABASE would be at risk */
if (strchr(location, '\''))
ereport(ERROR,
(errcode(ERRCODE_INVALID_NAME),
errmsg("tablespace location cannot contain single quotes")));
/*
* Allowing relative paths seems risky
*
* this also helps us ensure that location is not empty or whitespace
*/
if (!is_absolute_path(location))
ereport(ERROR,
(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
errmsg("tablespace location must be an absolute path")));
/*
* Check that location isn't too long. Remember that we're going to append
* 'PG_XXX/<dboid>/<relid>_<fork>.<nnn>'. FYI, we never actually
* reference the whole path here, but mkdir() uses the first two parts.
*/
if (strlen(location) + 1 + strlen(TABLESPACE_VERSION_DIRECTORY) + 1 +
OIDCHARS + 1 + OIDCHARS + 1 + FORKNAMECHARS + 1 + OIDCHARS > MAXPGPATH)
ereport(ERROR,
(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
errmsg("tablespace location \"%s\" is too long",
location)));
/* Warn if the tablespace is in the data directory. */
if (path_is_prefix_of_path(DataDir, location))
ereport(WARNING,
(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
errmsg("tablespace location should not be inside the data directory")));
/*
* Disallow creation of tablespaces named "pg_xxx"; we reserve this
* namespace for system purposes.
*/
if (!allowSystemTableMods && IsReservedName(stmt->tablespacename))
ereport(ERROR,
(errcode(ERRCODE_RESERVED_NAME),
errmsg("unacceptable tablespace name \"%s\"",
stmt->tablespacename),
errdetail("The prefix \"pg_\" is reserved for system tablespaces.")));
/*
* Check that there is no other tablespace by this name. (The unique
* index would catch this anyway, but might as well give a friendlier
* message.)
*/
if (OidIsValid(get_tablespace_oid(stmt->tablespacename, true)))
ereport(ERROR,
(errcode(ERRCODE_DUPLICATE_OBJECT),
errmsg("tablespace \"%s\" already exists",
stmt->tablespacename)));
/*
* Insert tuple into pg_tablespace. The purpose of doing this first is to
* lock the proposed tablename against other would-be creators. The
* insertion will roll back if we find problems below.
*/
rel = heap_open(TableSpaceRelationId, RowExclusiveLock);
MemSet(nulls, false, sizeof(nulls));
values[Anum_pg_tablespace_spcname - 1] =
DirectFunctionCall1(namein, CStringGetDatum(stmt->tablespacename));
values[Anum_pg_tablespace_spcowner - 1] =
ObjectIdGetDatum(ownerId);
nulls[Anum_pg_tablespace_spcacl - 1] = true;
/* Generate new proposed spcoptions (text array) */
newOptions = transformRelOptions((Datum) 0,
stmt->options,
NULL, NULL, false, false);
(void) tablespace_reloptions(newOptions, true);
if (newOptions != (Datum) 0)
values[Anum_pg_tablespace_spcoptions - 1] = newOptions;
else
nulls[Anum_pg_tablespace_spcoptions - 1] = true;
tuple = heap_form_tuple(rel->rd_att, values, nulls);
tablespaceoid = simple_heap_insert(rel, tuple);
CatalogUpdateIndexes(rel, tuple);
heap_freetuple(tuple);
/* Record dependency on owner */
recordDependencyOnOwner(TableSpaceRelationId, tablespaceoid, ownerId);
/* Post creation hook for new tablespace */
InvokeObjectPostCreateHook(TableSpaceRelationId, tablespaceoid, 0);
create_tablespace_directories(location, tablespaceoid);
/* Record the filesystem change in XLOG */
{
xl_tblspc_create_rec xlrec;
xlrec.ts_id = tablespaceoid;
XLogBeginInsert();
XLogRegisterData((char *) &xlrec,
offsetof(xl_tblspc_create_rec, ts_path));
XLogRegisterData((char *) location, strlen(location) + 1);
(void) XLogInsert(RM_TBLSPC_ID, XLOG_TBLSPC_CREATE);
}
/*
* Force synchronous commit, to minimize the window between creating the
* symlink on-disk and marking the transaction committed. It's not great
* that there is any window at all, but definitely we don't want to make
* it larger than necessary.
*/
ForceSyncCommit();
pfree(location);
/* We keep the lock on pg_tablespace until commit */
heap_close(rel, NoLock);
return tablespaceoid;
#else /* !HAVE_SYMLINK */
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("tablespaces are not supported on this platform")));
return InvalidOid; /* keep compiler quiet */
#endif /* HAVE_SYMLINK */
}