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openGauss-server/src/gausskernel/optimizer/commands/dbcommands.cpp

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/* -------------------------------------------------------------------------
*
* dbcommands.cpp
* Database management commands (create/drop database).
*
* Note: database creation/destruction commands use exclusive locks on
* the database objects (as expressed by LockSharedObject()) to avoid
* stepping on each others' toes. Formerly we used table-level locks
* on pg_database, but that's too coarse-grained.
*
* Portions Copyright (c) 2020 Huawei Technologies Co.,Ltd.
* Portions Copyright (c) 1996-2012, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
*
* IDENTIFICATION
* src/gausskernel/optimizer/commands/dbcommands.cpp
*
* -------------------------------------------------------------------------
*/
#include "postgres.h"
#include "knl/knl_variable.h"
#include <fcntl.h>
#include "executor/executor.h"
#include "access/genam.h"
#include "access/heapam.h"
#include "access/tableam.h"
#include "access/transam.h"
#include "access/xact.h"
#include "access/xloginsert.h"
#include "access/xlogutils.h"
#include "catalog/catalog.h"
#include "catalog/dependency.h"
#include "catalog/indexing.h"
#include "catalog/objectaccess.h"
#include "catalog/pg_authid.h"
#include "catalog/pg_database.h"
#include "catalog/pg_db_role_setting.h"
#include "catalog/pg_job.h"
#include "catalog/pg_proc.h"
#include "catalog/pg_tablespace.h"
#include "catalog/pgxc_slice.h"
#include "commands/comment.h"
#include "commands/dbcommands.h"
#include "commands/tablecmds.h"
#include "replication/slot.h"
#include "commands/sec_rls_cmds.h"
#include "commands/seclabel.h"
#include "commands/tablespace.h"
#include "mb/pg_wchar.h"
#include "miscadmin.h"
#include "pgstat.h"
#include "postmaster/bgwriter.h"
#include "rewrite/rewriteRlsPolicy.h"
#include "storage/copydir.h"
#include "storage/lmgr.h"
#include "storage/ipc.h"
#include "storage/procarray.h"
#include "storage/smgr.h"
#include "utils/acl.h"
#include "utils/builtins.h"
#include "utils/fmgroids.h"
#include "utils/inval.h"
#include "utils/memutils.h"
#include "utils/pg_locale.h"
#include "utils/sec_rls_utils.h"
#include "utils/snapmgr.h"
#include "utils/syscache.h"
#include "access/heapam.h"
#include "utils/timestamp.h"
#ifdef PGXC
#include "pgxc/execRemote.h"
#include "pgxc/pgxc.h"
#include "access/gtm.h"
#include "pgxc/poolutils.h"
#include "tcop/utility.h"
#endif
#include "storage/dfs/dfs_connector.h"
typedef struct {
Oid src_dboid; /* source (template) DB */
Oid dest_dboid; /* DB we are trying to create */
} createdb_failure_params;
typedef struct {
Oid dest_dboid; /* DB we are trying to move */
Oid dest_tsoid; /* tablespace we are trying to move to */
#ifdef PGXC
Oid src_tsoid; /* tablespace we are trying to move from */
#endif
} movedb_failure_params;
/* non-export function prototypes */
static void createdb_failure_callback(int code, Datum arg);
static void movedb(const char* dbname, const char* tblspcname);
static void movedb_failure_callback(int code, Datum arg);
static bool get_db_info(const char* name, LOCKMODE lockmode, Oid* dbIdP, Oid* ownerIdP, int* encodingP,
bool* dbIsTemplateP, bool* dbAllowConnP, Oid* dbLastSysOidP, TransactionId* dbFrozenXidP, Oid* dbTablespace,
char** dbCollate, char** dbCtype, char** src_compatibility = NULL);
static void remove_dbtablespaces(Oid db_id);
static bool check_db_file_conflict(Oid db_id);
static void createdb_xact_callback(bool isCommit, const void* arg);
static void movedb_xact_callback(bool isCommit, const void* arg);
static void movedb_success_callback(Oid db_id, Oid tblspcoid);
static void AlterDatabasePrivateObject(const Form_pg_database fbform, Oid dbid, bool enablePrivateObject);
/*
* Check if user is a logic cluster user
*/
bool userbindlc(Oid rolid)
{
if (!in_logic_cluster())
return false;
bool isNull = true;
HeapTuple tup = SearchSysCache1(AUTHOID, rolid);
if (!HeapTupleIsValid(tup))
ereport(ERROR, (errcode(ERRCODE_UNDEFINED_OBJECT), errmsg("cache lookup failed for role with oid %u", rolid)));
Datum datum = SysCacheGetAttr(AUTHOID, tup, Anum_pg_authid_rolnodegroup, &isNull);
if (!isNull) {
Oid groupoid = DatumGetObjectId(datum);
if (OidIsValid(groupoid))
return true;
}
ReleaseSysCache(tup);
return false;
}
/*
* CREATE DATABASE
*/
void createdb(const CreatedbStmt* stmt)
{
TableScanDesc scan;
Relation rel;
Oid src_dboid;
Oid src_owner;
int src_encoding;
char* src_collate = NULL;
char* src_ctype = NULL;
char* src_compatibility = NULL;
bool src_istemplate = false;
bool src_allowconn = false;
Oid src_lastsysoid;
TransactionId src_frozenxid;
Oid src_deftablespace;
volatile Oid dst_deftablespace;
Relation pg_database_rel;
HeapTuple tuple;
Datum new_record[Natts_pg_database];
bool new_record_nulls[Natts_pg_database];
Oid dboid;
Oid datdba;
ListCell* option = NULL;
DefElem* dtablespacename = NULL;
DefElem* downer = NULL;
DefElem* dtemplate = NULL;
DefElem* dencoding = NULL;
DefElem* dcollate = NULL;
DefElem* dctype = NULL;
DefElem* dcompatibility = NULL;
DefElem* dconnlimit = NULL;
char* dbname = stmt->dbname;
char* dbowner = NULL;
const char* dbtemplate = NULL;
char* dbcollate = NULL;
char* dbctype = NULL;
char* dbcompatibility = NULL;
char* canonname = NULL;
int encoding = -1;
int dbconnlimit = -1;
int notherbackends;
int npreparedxacts;
createdb_failure_params fparms;
Snapshot snapshot;
/* Extract options from the statement node tree */
foreach (option, stmt->options) {
DefElem* defel = (DefElem*)lfirst(option);
if (strcmp(defel->defname, "tablespace") == 0) {
if (dtablespacename != NULL)
ereport(ERROR, (errcode(ERRCODE_SYNTAX_ERROR), errmsg("conflicting or redundant options")));
dtablespacename = defel;
} else if (strcmp(defel->defname, "owner") == 0) {
if (downer != NULL)
ereport(ERROR, (errcode(ERRCODE_SYNTAX_ERROR), errmsg("conflicting or redundant options")));
downer = defel;
} else if (strcmp(defel->defname, "template") == 0) {
if (dtemplate != NULL)
ereport(ERROR, (errcode(ERRCODE_SYNTAX_ERROR), errmsg("conflicting or redundant options")));
dtemplate = defel;
} else if (strcmp(defel->defname, "encoding") == 0) {
if (dencoding != NULL)
ereport(ERROR, (errcode(ERRCODE_SYNTAX_ERROR), errmsg("conflicting or redundant options")));
dencoding = defel;
} else if (strcmp(defel->defname, "lc_collate") == 0) {
if (dcollate != NULL)
ereport(ERROR, (errcode(ERRCODE_SYNTAX_ERROR), errmsg("conflicting or redundant options")));
dcollate = defel;
} else if (strcmp(defel->defname, "lc_ctype") == 0) {
if (dctype != NULL)
ereport(ERROR, (errcode(ERRCODE_SYNTAX_ERROR), errmsg("conflicting or redundant options")));
dctype = defel;
} else if (strcmp(defel->defname, "connectionlimit") == 0) {
if (dconnlimit != NULL)
ereport(ERROR, (errcode(ERRCODE_SYNTAX_ERROR), errmsg("conflicting or redundant options")));
dconnlimit = defel;
} else if (strcmp(defel->defname, "dbcompatibility") == 0) {
if (dcompatibility != NULL)
ereport(ERROR, (errcode(ERRCODE_SYNTAX_ERROR), errmsg("conflicting or redundant options")));
dcompatibility = defel;
} else if (strcmp(defel->defname, "location") == 0) {
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("LOCATION is not supported anymore"),
errhint("Consider using tablespaces instead.")));
} else
ereport(ERROR, (errcode(ERRCODE_SYNTAX_ERROR), errmsg("option \"%s\" not recognized", defel->defname)));
}
if (downer != NULL && downer->arg != NULL)
dbowner = strVal(downer->arg);
if (dtemplate != NULL && dtemplate->arg != NULL) {
dbtemplate = strVal(dtemplate->arg);
/* make sure template is from template0 */
if (strcmp(dbtemplate, "template0") != 0) {
ereport(ERROR, (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("%s is not supported for using here, just support template0", dbtemplate)));
}
}
if (dencoding != NULL && dencoding->arg != NULL) {
const char* encoding_name = NULL;
if (IsA(dencoding->arg, Integer)) {
encoding = intVal(dencoding->arg);
encoding_name = pg_encoding_to_char(encoding);
if (strcmp(encoding_name, "") == 0 || pg_valid_server_encoding(encoding_name) < 0)
ereport(
ERROR, (errcode(ERRCODE_UNDEFINED_OBJECT), errmsg("%d is not a valid encoding code", encoding)));
} else if (IsA(dencoding->arg, String)) {
encoding_name = strVal(dencoding->arg);
encoding = pg_valid_server_encoding(encoding_name);
if (encoding < 0)
ereport(ERROR,
(errcode(ERRCODE_UNDEFINED_OBJECT), errmsg("%s is not a valid encoding name", encoding_name)));
} else
ereport(ERROR,
(errcode(ERRCODE_UNRECOGNIZED_NODE_TYPE),
errmsg("unrecognized node type: %d", nodeTag(dencoding->arg))));
}
if (dcollate != NULL && dcollate->arg != NULL)
dbcollate = strVal(dcollate->arg);
if (dctype != NULL && dctype->arg != NULL)
dbctype = strVal(dctype->arg);
if (dcompatibility != NULL && dcompatibility->arg != NULL) {
dbcompatibility = strVal(dcompatibility->arg);
}
if (dconnlimit != NULL && dconnlimit->arg != NULL) {
dbconnlimit = intVal(dconnlimit->arg);
if (dbconnlimit < -1)
ereport(
ERROR, (errcode(ERRCODE_INVALID_PARAMETER_VALUE), errmsg("invalid connection limit: %d", dbconnlimit)));
}
/* obtain OID of proposed owner */
if (dbowner != NULL)
datdba = get_role_oid(dbowner, false);
else
datdba = GetUserId();
/*
* To create a database, must have createdb privilege and must be able to
* become the target role (this does not imply that the target role itself
* must have createdb privilege). The latter provision guards against
* "giveaway" attacks. Note that a superuser will always have both of
* these privileges a fortiori.
*/
if (!have_createdb_privilege())
ereport(ERROR, (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE), errmsg("permission denied to create database")));
check_is_member_of_role(GetUserId(), datdba);
if (userbindlc(datdba))
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE), errmsg("database cannot be owned by logic cluster user.")));
/*
* Lookup database (template) to be cloned, and obtain share lock on it.
* ShareLock allows two CREATE DATABASEs to work from the same template
* concurrently, while ensuring no one is busy dropping it in parallel
* (which would be Very Bad since we'd likely get an incomplete copy
* without knowing it). This also prevents any new connections from being
* made to the source until we finish copying it, so we can be sure it
* won't change underneath us.
*/
if (dbtemplate == NULL) {
if (IsBootstrapProcessingMode() || !IsUnderPostmaster) {
/* When initdb called make sure template0 and postgres can be created by template1 successfully */
dbtemplate = "template1";
} else {
/* Default template database name */
dbtemplate = "template0";
}
}
if (!get_db_info(
dbtemplate,
ShareLock,
&src_dboid,
&src_owner,
&src_encoding,
&src_istemplate,
&src_allowconn,
&src_lastsysoid,
&src_frozenxid,
&src_deftablespace,
&src_collate,
&src_ctype,
&src_compatibility)) {
ereport(ERROR,
(errcode(ERRCODE_UNDEFINED_DATABASE), errmsg("template database \"%s\" does not exist", dbtemplate)));
}
/*
* Permission check: to copy a DB that's not marked datistemplate, you
* must be superuser or the owner thereof.
*/
if (!src_istemplate) {
if (!pg_database_ownercheck(src_dboid, GetUserId()))
ereport(ERROR,
(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
errmsg("permission denied to copy database \"%s\"", dbtemplate)));
}
/* If encoding or locales are defaulted, use source's setting */
if (encoding < 0) {
encoding = src_encoding;
}
if (dbcollate == NULL)
dbcollate = src_collate;
if (dbctype == NULL)
dbctype = src_ctype;
if (dbcompatibility == NULL)
dbcompatibility = src_compatibility;
/* Some encodings are client only */
if (!PG_VALID_BE_ENCODING(encoding))
ereport(ERROR, (errcode(ERRCODE_WRONG_OBJECT_TYPE), errmsg("invalid server encoding %d", encoding)));
/* Check that the chosen locales are valid, and get canonical spellings */
if (!check_locale(LC_COLLATE, dbcollate, &canonname))
ereport(ERROR, (errcode(ERRCODE_WRONG_OBJECT_TYPE), errmsg("invalid locale name: \"%s\"", dbcollate)));
dbcollate = canonname;
if (!check_locale(LC_CTYPE, dbctype, &canonname))
ereport(ERROR, (errcode(ERRCODE_WRONG_OBJECT_TYPE), errmsg("invalid locale name: \"%s\"", dbctype)));
dbctype = canonname;
check_encoding_locale_matches(encoding, dbcollate, dbctype);
/*
* Check that the new encoding and locale settings match the source
* database. We insist on this because we simply copy the source data ---
* any non-ASCII data would be wrongly encoded, and any indexes sorted
* according to the source locale would be wrong.
*
* However, we assume that template0 doesn't contain any non-ASCII data
* nor any indexes that depend on collation or ctype, so template0 can be
* used as template for creating a database with any encoding or locale.
*/
if (strcmp(dbtemplate, "template0") != 0) {
if (encoding != src_encoding)
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("new encoding (%s) is incompatible with the encoding of the template database (%s)",
pg_encoding_to_char(encoding),
pg_encoding_to_char(src_encoding)),
errhint("Use the same encoding as in the template database, or use template0 as template.")));
if (strcmp(dbcollate, src_collate) != 0)
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("new collation (%s) is incompatible with the collation of the template database (%s)",
dbcollate,
src_collate),
errhint("Use the same collation as in the template database, or use template0 as template.")));
if (strcmp(dbctype, src_ctype) != 0)
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("new LC_CTYPE (%s) is incompatible with the LC_CTYPE of the template database (%s)",
dbctype,
src_ctype),
errhint("Use the same LC_CTYPE as in the template database, or use template0 as template.")));
}
/* Resolve default tablespace for new database */
if (dtablespacename != NULL && dtablespacename->arg != NULL) {
char* tablespacename = NULL;
AclResult aclresult;
tablespacename = strVal(dtablespacename->arg);
dst_deftablespace = get_tablespace_oid(tablespacename, false);
/* check permissions */
aclresult = pg_tablespace_aclcheck(dst_deftablespace, GetUserId(), ACL_CREATE);
if (aclresult != ACLCHECK_OK)
aclcheck_error(aclresult, ACL_KIND_TABLESPACE, tablespacename);
/* pg_global must never be the default tablespace */
if (dst_deftablespace == GLOBALTABLESPACE_OID)
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE), errmsg("pg_global cannot be used as default tablespace")));
if (IsSpecifiedTblspc(dst_deftablespace, FILESYSTEM_HDFS)) {
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("DFS tablespace can not be used as default tablespace.")));
}
/*
* If we are trying to change the default tablespace of the template,
* we require that the template not have any files in the new default
* tablespace. This is necessary because otherwise the copied
* database would contain pg_class rows that refer to its default
* tablespace both explicitly (by OID) and implicitly (as zero), which
* would cause problems. For example another CREATE DATABASE using
* the copied database as template, and trying to change its default
* tablespace again, would yield outright incorrect results (it would
* improperly move tables to the new default tablespace that should
* stay in the same tablespace).
*/
if (dst_deftablespace != src_deftablespace) {
char* srcpath = NULL;
struct stat st;
srcpath = GetDatabasePath(src_dboid, dst_deftablespace);
if (stat(srcpath, &st) == 0 && S_ISDIR(st.st_mode) && !directory_is_empty(srcpath))
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("cannot assign new default tablespace \"%s\"", tablespacename),
errdetail(
"There is a conflict because database \"%s\" already has some tables in this tablespace.",
dbtemplate)));
pfree_ext(srcpath);
}
} else {
/* Use template database's default tablespace */
dst_deftablespace = src_deftablespace;
/* Note there is no additional permission check in this path */
}
/*
* Check for db name conflict. This is just to give a more friendly error
* message than "unique index violation". There's a race condition but
* we're willing to accept the less friendly message in that case.
*/
if (OidIsValid(get_database_oid(dbname, true)))
ereport(ERROR, (errcode(ERRCODE_DUPLICATE_DATABASE), errmsg("database \"%s\" already exists", dbname)));
/*
* The source DB can't have any active backends, except this one
* (exception is to allow CREATE DB while connected to template1).
* Otherwise we might copy inconsistent data.
*
* This should be last among the basic error checks, because it involves
* potential waiting; we may as well throw an error first if we're gonna
* throw one.
*/
LockDatabaseObject(DatabaseRelationId, src_dboid, 0, AccessExclusiveLock);
if (CountOtherDBBackends(src_dboid, &notherbackends, &npreparedxacts))
ereport(ERROR,
(errcode(ERRCODE_OBJECT_IN_USE),
errmsg("source database \"%s\" is being accessed by other users", dbtemplate),
errdetail_busy_db(notherbackends, npreparedxacts)));
/*
* Select an OID for the new database, checking that it doesn't have a
* filename conflict with anything already existing in the tablespace
* directories.
*/
pg_database_rel = heap_open(DatabaseRelationId, RowExclusiveLock);
do {
dboid = GetNewOid(pg_database_rel);
} while (check_db_file_conflict(dboid));
/*
* Insert a new tuple into pg_database. This establishes our ownership of
* the new database name (anyone else trying to insert the same name will
* block on the unique index, and fail after we commit).
*/
/* Form tuple */
errno_t rc = memset_s(new_record, sizeof(new_record), 0, sizeof(new_record));
securec_check(rc, "", "");
rc = memset_s(new_record_nulls, sizeof(new_record_nulls), 0, sizeof(new_record_nulls));
securec_check(rc, "", "");
new_record[Anum_pg_database_datname - 1] = DirectFunctionCall1(namein, CStringGetDatum(dbname));
new_record[Anum_pg_database_datdba - 1] = ObjectIdGetDatum(datdba);
new_record[Anum_pg_database_encoding - 1] = Int32GetDatum(encoding);
new_record[Anum_pg_database_datcollate - 1] = DirectFunctionCall1(namein, CStringGetDatum(dbcollate));
new_record[Anum_pg_database_datctype - 1] = DirectFunctionCall1(namein, CStringGetDatum(dbctype));
new_record[Anum_pg_database_datistemplate - 1] = BoolGetDatum(false);
new_record[Anum_pg_database_datallowconn - 1] = BoolGetDatum(true);
new_record[Anum_pg_database_datconnlimit - 1] = Int32GetDatum(dbconnlimit);
new_record[Anum_pg_database_datlastsysoid - 1] = ObjectIdGetDatum(src_lastsysoid);
new_record[Anum_pg_database_datfrozenxid - 1] = ShortTransactionIdGetDatum(src_frozenxid);
new_record[Anum_pg_database_dattablespace - 1] = ObjectIdGetDatum(dst_deftablespace);
new_record[Anum_pg_database_compatibility - 1] = DirectFunctionCall1(namein, CStringGetDatum(dbcompatibility));
/*
* We deliberately set datacl to default (NULL), rather than copying it
* from the template database. Copying it would be a bad idea when the
* owner is not the same as the template's owner.
*/
new_record_nulls[Anum_pg_database_datacl - 1] = true;
new_record[Anum_pg_database_datfrozenxid64 - 1] = TransactionIdGetDatum(src_frozenxid);
tuple = heap_form_tuple(RelationGetDescr(pg_database_rel), new_record, new_record_nulls);
HeapTupleSetOid(tuple, dboid);
(void)simple_heap_insert(pg_database_rel, tuple);
/* Update indexes */
CatalogUpdateIndexes(pg_database_rel, tuple);
/*
* Now generate additional catalog entries associated with the new DB
*/
/* Register owner dependency */
recordDependencyOnOwner(DatabaseRelationId, dboid, datdba);
/* Create pg_shdepend entries for objects within database */
copyTemplateDependencies(src_dboid, dboid);
/* Post creation hook for new database */
InvokeObjectAccessHook(OAT_POST_CREATE, DatabaseRelationId, dboid, 0, NULL);
/*
* Force a checkpoint before starting the copy. This will force dirty
* buffers out to disk, to ensure source database is up-to-date on disk
* for the copy. FlushDatabaseBuffers() would suffice for that, but we
* also want to process any pending unlink requests. Otherwise, if a
* checkpoint happened while we're copying files, a file might be deleted
* just when we're about to copy it, causing the lstat() call in copydir()
* to fail with ENOENT.
*/
RequestCheckpoint(CHECKPOINT_IMMEDIATE | CHECKPOINT_FORCE | CHECKPOINT_WAIT);
/*
* Take an MVCC snapshot to use while scanning through pg_tablespace. For
* safety, register the snapshot (this prevents it from changing if
* something else were to request a snapshot during the loop).
*
* Traversing pg_tablespace with an MVCC snapshot is necessary to provide
* us with a consistent view of the tablespaces that exist. Using
* SnapshotNow here would risk seeing the same tablespace multiple times,
* or worse not seeing a tablespace at all, if its tuple is moved around
* by a concurrent update (eg an ACL change).
*
* Inconsistency of this sort is inherent to all SnapshotNow scans, unless
* some lock is held to prevent concurrent updates of the rows being
* sought. There should be a generic fix for that, but in the meantime
* it's worth fixing this case in particular because we are doing very
* heavyweight operations within the scan, so that the elapsed time for
* the scan is vastly longer than for most other catalog scans. That
* means there's a much wider window for concurrent updates to cause
* trouble here than anywhere else. XXX this code should be changed
* whenever a generic fix is implemented.
*/
snapshot = RegisterSnapshot(GetLatestSnapshot());
/*
* Once we start copying subdirectories, we need to be able to clean 'em
* up if we fail. Use an ENSURE block to make sure this happens. (This
* is not a 100% solution, because of the possibility of failure during
* transaction commit after we leave this routine, but it should handle
* most scenarios.)
*/
fparms.src_dboid = src_dboid;
fparms.dest_dboid = dboid;
PG_ENSURE_ERROR_CLEANUP(createdb_failure_callback, PointerGetDatum(&fparms));
{
/*
* Iterate through all tablespaces of the template database, and copy
* each one to the new database.
*/
rel = heap_open(TableSpaceRelationId, AccessShareLock);
scan = tableam_scan_begin(rel, snapshot, 0, NULL);
while ((tuple = (HeapTuple) tableam_scan_getnexttuple(scan, ForwardScanDirection)) != NULL) {
Oid srctablespace = HeapTupleGetOid(tuple);
Oid dsttablespace;
char* srcpath = NULL;
char* dstpath = NULL;
struct stat st;
/* No need to copy global tablespace */
if (srctablespace == GLOBALTABLESPACE_OID)
continue;
srcpath = GetDatabasePath(src_dboid, srctablespace);
if (stat(srcpath, &st) < 0 || !S_ISDIR(st.st_mode) || directory_is_empty(srcpath)) {
/* Assume we can ignore it */
pfree_ext(srcpath);
continue;
}
if (srctablespace == src_deftablespace)
dsttablespace = dst_deftablespace;
else
dsttablespace = srctablespace;
dstpath = GetDatabasePath(dboid, dsttablespace);
/*
* Copy this subdirectory to the new location
*
* We don't need to copy subdirectories
*/
(void)copydir(srcpath, dstpath, false, ERROR);
/* Record the filesystem change in XLOG */
{
xl_dbase_create_rec xlrec;
xlrec.db_id = dboid;
xlrec.tablespace_id = dsttablespace;
xlrec.src_db_id = src_dboid;
xlrec.src_tablespace_id = srctablespace;
XLogBeginInsert();
XLogRegisterData((char*)&xlrec, sizeof(xl_dbase_create_rec));
(void)XLogInsert(RM_DBASE_ID, XLOG_DBASE_CREATE | XLR_SPECIAL_REL_UPDATE);
}
}
tableam_scan_end(scan);
heap_close(rel, AccessShareLock);
/*
* We force a checkpoint before committing. This effectively means
* that committed XLOG_DBASE_CREATE operations will never need to be
* replayed (at least not in ordinary crash recovery; we still have to
* make the XLOG entry for the benefit of PITR operations). This
* avoids two nasty scenarios:
*
* #1: When PITR is off, we don't XLOG the contents of newly created
* indexes; therefore the drop-and-recreate-whole-directory behavior
* of DBASE_CREATE replay would lose such indexes.
*
* #2: Since we have to recopy the source database during DBASE_CREATE
* replay, we run the risk of copying changes in it that were
* committed after the original CREATE DATABASE command but before the
* system crash that led to the replay. This is at least unexpected
* and at worst could lead to inconsistencies, eg duplicate table
* names.
*
* (Both of these were real bugs in releases 8.0 through 8.0.3.)
*
* In PITR replay, the first of these isn't an issue, and the second
* is only a risk if the CREATE DATABASE and subsequent template
* database change both occur while a base backup is being taken.
* There doesn't seem to be much we can do about that except document
* it as a limitation.
*
* Perhaps if we ever implement CREATE DATABASE in a less cheesy way,
* we can avoid this.
*/
RequestCheckpoint(CHECKPOINT_IMMEDIATE | CHECKPOINT_FORCE | CHECKPOINT_WAIT);
/*
* Wait for last checkpoint sync to standby and then flush the latest lsn to disk;
*/
WaitCheckpointSync();
CheckPointReplicationSlots();
/*
* Close pg_database, but keep lock till commit.
*/
heap_close(pg_database_rel, NoLock);
/*
* Force synchronous commit, thus minimizing the window between
* creation of the database files and commital of the transaction. If
* we crash before committing, we'll have a DB that's taking up disk
* space but is not in pg_database, which is not good.
*/
ForceSyncCommit();
}
PG_END_ENSURE_ERROR_CLEANUP(createdb_failure_callback, PointerGetDatum(&fparms));
/* Free our snapshot */
UnregisterSnapshot(snapshot);
#ifdef PGXC
/*
* Even if we are successful, ultimately this transaction can be aborted
* because some other node failed. So arrange for cleanup on transaction
* abort.
* Unregistering snapshot above, will not have any problem when the
* callback function is executed because the callback register's its
* own snapshot in function remove_dbtablespaces
*/
set_dbcleanup_callback(createdb_xact_callback, &fparms.dest_dboid, sizeof(fparms.dest_dboid));
#endif
}
/*
* Check whether chosen encoding matches chosen locale settings. This
* restriction is necessary because libc's locale-specific code usually
* fails when presented with data in an encoding it's not expecting. We
* allow mismatch in four cases:
*
* 1. locale encoding = SQL_ASCII, which means that the locale is C/POSIX
* which works with any encoding.
*
* 2. locale encoding = -1, which means that we couldn't determine the
* locale's encoding and have to trust the user to get it right.
*
* 3. selected encoding is UTF8 and platform is win32. This is because
* UTF8 is a pseudo codepage that is supported in all locales since it's
* converted to UTF16 before being used.
*
* 4. selected encoding is SQL_ASCII, but only if you're a superuser. This
* is risky but we have historically allowed it --- notably, the
* regression tests require it.
*
* Note: if you change this policy, fix initdb to match.
*/
void check_encoding_locale_matches(int encoding, const char* collate, const char* ctype)
{
int ctype_encoding;
int collate_encoding;
AutoMutexLock localeLock(&gLocaleMutex);
localeLock.lock();
ctype_encoding = pg_get_encoding_from_locale(ctype, true);
collate_encoding = pg_get_encoding_from_locale(collate, true);
localeLock.unLock();
if (!(ctype_encoding == encoding || ctype_encoding == PG_SQL_ASCII || ctype_encoding == -1 ||
#ifdef WIN32
encoding == PG_UTF8 ||
#endif
(encoding == PG_SQL_ASCII && superuser())))
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("encoding \"%s\" does not match locale \"%s\"", pg_encoding_to_char(encoding), ctype),
errdetail(
"The chosen LC_CTYPE setting requires encoding \"%s\".", pg_encoding_to_char(ctype_encoding))));
if (!(collate_encoding == encoding || collate_encoding == PG_SQL_ASCII || collate_encoding == -1 ||
#ifdef WIN32
encoding == PG_UTF8 ||
#endif
(encoding == PG_SQL_ASCII && superuser())))
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("encoding \"%s\" does not match locale \"%s\"", pg_encoding_to_char(encoding), collate),
errdetail(
"The chosen LC_COLLATE setting requires encoding \"%s\".", pg_encoding_to_char(collate_encoding))));
}
#ifdef PGXC
/*
* Error cleanup callback for createdb. Aftec createdb() succeeds, the
* transaction can still be aborted due to other nodes. So on abort-transaction,
* this function is called to do the cleanup. This involves removing directories
* created after successful completion.
* Nothing to be done on commit.
*/
static void createdb_xact_callback(bool isCommit, const void* arg)
{
if (isCommit)
return;
/* Throw away any successfully copied subdirectories */
remove_dbtablespaces(*(Oid*)arg);
}
#endif
/* Error cleanup callback for createdb */
static void createdb_failure_callback(int code, Datum arg)
{
createdb_failure_params* fparms = (createdb_failure_params*)DatumGetPointer(arg);
/*
* Release lock on source database before doing recursive remove. This is
* not essential but it seems desirable to release the lock as soon as
* possible.
*/
UnlockSharedObject(DatabaseRelationId, fparms->src_dboid, 0, ShareLock);
/* Throw away any successfully copied subdirectories */
remove_dbtablespaces(fparms->dest_dboid);
}
void ts_dropdb_xact_callback(bool isCommit, const void* arg)
{
Oid* db_oid = (Oid*)arg;
if (!isCommit) {
*db_oid = InvalidOid;
}
(void)pg_atomic_sub_fetch_u32(&g_instance.ts_compaction_cxt.drop_db_count, 1);
ereport(LOG, (errmodule(MOD_TIMESERIES), errcode(ERRCODE_LOG),
errmsg("drop db callback have drop db session count after subtract %u",
pg_atomic_read_u32(&g_instance.ts_compaction_cxt.drop_db_count))));
}
#ifdef ENABLE_MULTIPLE_NODES
void handle_compaction_dropdb(const char* dbname)
{
/**
* if timeseries db and compaction working, send sigusr1 to compaction producer
* signal will block producer switch session.
*/
if (!IS_PGXC_DATANODE) {
return;
}
if (g_instance.attr.attr_common.enable_tsdb && u_sess->attr.attr_common.enable_ts_compaction) {
Oid drop_databse_oid = get_database_oid(dbname, false);
(void)pg_atomic_add_fetch_u32(&g_instance.ts_compaction_cxt.drop_db_count, 1);
g_instance.ts_compaction_cxt.dropdb_id = drop_databse_oid;
ereport(LOG, (errmodule(MOD_TIMESERIES), errcode(ERRCODE_LOG),
errmsg("drop db callback have drop db session count after add %u",
pg_atomic_read_u32(&g_instance.ts_compaction_cxt.drop_db_count))));
while (!g_instance.ts_compaction_cxt.compaction_rest &&
g_instance.ts_compaction_cxt.state == Compaction::COMPACTION_IN_PROGRESS) {
pg_usleep(100 * USECS_PER_MSEC);
}
set_dbcleanup_callback(ts_dropdb_xact_callback, &g_instance.ts_compaction_cxt.dropdb_id,
sizeof(g_instance.ts_compaction_cxt.dropdb_id));
}
}
#endif
/*
* DROP DATABASE
*/
void dropdb(const char* dbname, bool missing_ok)
{
Oid db_id;
bool db_istemplate = false;
Relation pgdbrel;
HeapTuple tup;
int notherbackends;
int npreparedxacts;
/* If we will return before reaching function end, please release this lock */
LWLockAcquire(DelayDDLLock, LW_SHARED);
if (!XLogRecPtrIsInvalid(GetDDLDelayStartPtr()))
ereport(ERROR,
(errcode(ERRCODE_OBJECT_IN_USE),
errmsg("could not drop database "
"while ddl delay function is enabled")));
#ifdef ENABLE_MULTIPLE_NODES
handle_compaction_dropdb(dbname);
#endif
/*
* Look up the target database's OID, and get exclusive lock on it. We
* need this to ensure that no new backend starts up in the target
* database while we are deleting it (see postinit.c), and that no one is
* using it as a CREATE DATABASE template or trying to delete it for
* themselves.
*/
pgdbrel = heap_open(DatabaseRelationId, RowExclusiveLock);
if (!get_db_info(
dbname, AccessExclusiveLock, &db_id, NULL, NULL, &db_istemplate, NULL, NULL, NULL, NULL, NULL, NULL)) {
if (!missing_ok) {
ereport(ERROR, (errcode(ERRCODE_UNDEFINED_DATABASE), errmsg("database \"%s\" does not exist", dbname)));
} else {
/* Close pg_database, release the lock, since we changed nothing */
heap_close(pgdbrel, RowExclusiveLock);
ereport(NOTICE, (errmsg("database \"%s\" does not exist, skipping", dbname)));
LWLockRelease(DelayDDLLock);
return;
}
}
gs_lock_test_and_set_64(&g_instance.stat_cxt.NodeStatResetTime, GetCurrentTimestamp());
/*
* Permission checks
*/
AclResult aclresult = pg_database_aclcheck(db_id, GetUserId(), ACL_DROP);
if (aclresult != ACLCHECK_OK && !pg_database_ownercheck(db_id, GetUserId())) {
aclcheck_error(ACLCHECK_NO_PRIV, ACL_KIND_DATABASE, dbname);
}
/* DROP hook for the database being removed */
if (object_access_hook) {
ObjectAccessDrop drop_arg;
errno_t rc = memset_s(&drop_arg, sizeof(ObjectAccessDrop), 0, sizeof(ObjectAccessDrop));
securec_check(rc, "\0", "\0");
InvokeObjectAccessHook(OAT_DROP, DatabaseRelationId, db_id, 0, &drop_arg);
}
/*
* Disallow dropping a DB that is marked istemplate. This is just to
* prevent people from accidentally dropping template0 or template1; they
* can do so if they're really determined ...
*/
if (db_istemplate)
ereport(ERROR, (errcode(ERRCODE_WRONG_OBJECT_TYPE), errmsg("cannot drop a template database")));
/* Obviously can't drop my own database */
if (db_id == u_sess->proc_cxt.MyDatabaseId)
ereport(ERROR, (errcode(ERRCODE_OBJECT_IN_USE), errmsg("cannot drop the currently open database")));
if (0 == strcmp(dbname, DEFAULT_DATABASE))
ereport(ERROR, (errcode(ERRCODE_WRONG_OBJECT_TYPE), errmsg("cannot drop the default database")));
/*
* Check for other backends in the target database. (Because we hold the
* database lock, no new ones can start after this.)
*
* As in CREATE DATABASE, check this after other error conditions.
*/
if (CountOtherDBBackends(db_id, &notherbackends, &npreparedxacts))
ereport(ERROR,
(errcode(ERRCODE_OBJECT_IN_USE),
errmsg("Database \"%s\" is being accessed by other users. You can stop all connections by command:"
" \"clean connection to all force for database XXXX;\" or wait for the sessions to end by querying "
"view: \"pg_stat_activity\".", dbname),
errdetail_busy_db(notherbackends, npreparedxacts)));
/* Search need delete use-defined C fun library.*/
prepareDatabaseCFunLibrary(db_id);
/* Relate to remove all job belong the database. */
remove_job_by_oid(dbname, DbOid, true);
/* Search need delete use-defined dictionary. */
deleteDatabaseTSFile(db_id);
/*
* Remove the database's tuple from pg_database.
*/
tup = SearchSysCache1(DATABASEOID, ObjectIdGetDatum(db_id));
if (!HeapTupleIsValid(tup))
ereport(ERROR, (errcode(ERRCODE_CACHE_LOOKUP_FAILED), errmsg("cache lookup failed for database %u", db_id)));
simple_heap_delete(pgdbrel, &tup->t_self);
ReleaseSysCache(tup);
/*
* Delete any comments or security labels associated with the database.
*/
DeleteSharedComments(db_id, DatabaseRelationId);
DeleteSharedSecurityLabel(db_id, DatabaseRelationId);
/*
* Remove settings associated with this database
*/
DropSetting(db_id, InvalidOid);
/*
* Remove shared dependency references for the database.
*/
dropDatabaseDependencies(db_id);
/*
* Request an immediate checkpoint to flush all the dirty pages in share buffer
* before we drop the related buffer pages under the database to keep consistent
* with the principle of checkpoint.
*/
RequestCheckpoint(CHECKPOINT_IMMEDIATE | CHECKPOINT_FORCE | CHECKPOINT_WAIT);
/*
* Drop pages for this database that are in the shared buffer cache. This
* is important to ensure that no remaining backend tries to write out a
* dirty buffer to the dead database later...
*/
DropDatabaseBuffers(db_id);
/*
* Tell the stats collector to forget it immediately, too.
*/
pgstat_drop_database(db_id);
/*
* Tell checkpointer to forget any pending fsync and unlink requests for
* files in the database; else the fsyncs will fail at next checkpoint, or
* worse, it will delete files that belong to a newly created database
* with the same OID.
*/
ForgetDatabaseFsyncRequests(db_id);
/*
* Force a checkpoint to make sure the checkpointer has received the
* message sent by ForgetDatabaseFsyncRequests. On Windows, this also
* ensures that background procs don't hold any open files, which would
* cause rmdir() to fail.
*/
RequestCheckpoint(CHECKPOINT_IMMEDIATE | CHECKPOINT_FORCE | CHECKPOINT_WAIT);
/*
* Remove all tablespace subdirs belonging to the database.
*/
remove_dbtablespaces(db_id);
/*
* Close pg_database, but keep lock till commit.
*/
heap_close(pgdbrel, NoLock);
/*
* Force synchronous commit, thus minimizing the window between removal of
* the database files and commital of the transaction. If we crash before
* committing, we'll have a DB that's gone on disk but still there
* according to pg_database, which is not good.
*/
ForceSyncCommit();
#ifdef PGXC
/* Drop sequences on gtm that are on the database dropped. */
if (IS_PGXC_COORDINATOR && !IsConnFromCoord())
if (DropSequenceGTM(0, dbname))
ereport(LOG,
(errcode(ERRCODE_SQL_STATEMENT_NOT_YET_COMPLETE),
errmsg("Deletion of sequences on database %s not completed", dbname)));
#endif
LWLockRelease(DelayDDLLock);
ereport(LOG,(errmsg("drop database \"%s\", id is %u", dbname, db_id)));
/* need calculate user used space info */
g_instance.comm_cxt.force_cal_space_info = true;
/* Drop local connection for dbname */
if(IS_PGXC_COORDINATOR) {
DropDBCleanConnection(dbname);
}
}
/*
* Must be owner or have alter privilege to alter database
*/
static void AlterDatabasePermissionCheck(Oid dboid, const char* dbname)
{
AclResult aclresult = pg_database_aclcheck(dboid, GetUserId(), ACL_ALTER);
if (aclresult != ACLCHECK_OK && !pg_database_ownercheck(dboid, GetUserId())) {
aclcheck_error(ACLCHECK_NO_PRIV, ACL_KIND_DATABASE, dbname);
}
}
/*
* Rename database
*/
void RenameDatabase(const char* oldname, const char* newname)
{
Oid db_id;
HeapTuple newtup;
Relation rel;
int notherbackends;
int npreparedxacts;
List* existTblSpcList = NIL;
/*
* Look up the target database's OID, and get exclusive lock on it. We
* need this for the same reasons as DROP DATABASE.
*/
rel = heap_open(DatabaseRelationId, RowExclusiveLock);
if (!get_db_info(oldname, AccessExclusiveLock, &db_id, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL))
ereport(ERROR, (errcode(ERRCODE_UNDEFINED_DATABASE), errmsg("database \"%s\" does not exist", oldname)));
/* Permission check. */
AlterDatabasePermissionCheck(db_id, oldname);
/* must have createdb rights */
if (!have_createdb_privilege())
ereport(ERROR, (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE), errmsg("permission denied to rename database")));
/*
* Make sure the new name doesn't exist. See notes for same error in
* CREATE DATABASE.
*/
if (OidIsValid(get_database_oid(newname, true)))
ereport(ERROR, (errcode(ERRCODE_DUPLICATE_DATABASE), errmsg("database \"%s\" already exists", newname)));
/*
* XXX Client applications probably store the current database somewhere,
* so renaming it could cause confusion. On the other hand, there may not
* be an actual problem besides a little confusion, so think about this
* and decide.
*/
if (db_id == u_sess->proc_cxt.MyDatabaseId)
ereport(ERROR, (errcode(ERRCODE_FEATURE_NOT_SUPPORTED), errmsg("current database cannot be renamed")));
/*
* Make sure the database does not have active sessions. This is the same
* concern as above, but applied to other sessions.
*
* As in CREATE DATABASE, check this after other error conditions.
*/
if (CountOtherDBBackends(db_id, &notherbackends, &npreparedxacts))
ereport(ERROR,
(errcode(ERRCODE_OBJECT_IN_USE),
errmsg("database \"%s\" is being accessed by other users", oldname),
errdetail_busy_db(notherbackends, npreparedxacts)));
existTblSpcList = HDFSTablespaceDirExistDatabase(db_id);
if (existTblSpcList != NIL) {
StringInfo existTblspc = (StringInfo)linitial(existTblSpcList);
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("It is unsupported to rename database \"%s\" on DFS tablespace \"%s\".",
oldname,
existTblspc->data)));
}
/* rename */
newtup = SearchSysCacheCopy1(DATABASEOID, ObjectIdGetDatum(db_id));
if (!HeapTupleIsValid(newtup))
ereport(ERROR, (errcode(ERRCODE_CACHE_LOOKUP_FAILED), errmsg("cache lookup failed for database %u", db_id)));
(void)namestrcpy(&(((Form_pg_database)GETSTRUCT(newtup))->datname), newname);
simple_heap_update(rel, &newtup->t_self, newtup);
CatalogUpdateIndexes(rel, newtup);
/* update sequence info */
if (IS_PGXC_COORDINATOR && !IsConnFromCoord()) {
RenameSequenceGTM((char*)oldname, (char*)newname, GTM_SEQ_DB_NAME);
}
/*
* Close pg_database, but keep lock till commit.
*/
heap_close(rel, NoLock);
}
/*
* Whether Check existance of a database with given db_id in
* HDFS tablesacpe or not.
* @_in_param db_id: The database oid to be checked.
* @return Return StringInfo list of tablespace name if exists, otherwise return
* NIL.
*/
List* HDFSTablespaceDirExistDatabase(Oid db_id)
{
return NIL;
}
#ifdef PGXC
/*
* IsSetTableSpace:
* Returns true if it is ALTER DATABASE SET TABLESPACE
*/
bool IsSetTableSpace(AlterDatabaseStmt* stmt)
{
ListCell* option = NULL;
/* Handle the SET TABLESPACE option separately */
foreach (option, stmt->options) {
DefElem* defel = (DefElem*)lfirst(option);
if (strcmp(defel->defname, "tablespace") == 0)
return true;
}
return false;
}
#endif
/*
* ALTER DATABASE SET TABLESPACE
*/
static void movedb(const char* dbname, const char* tblspcname)
{
Oid db_id;
Relation pgdbrel;
int notherbackends;
int npreparedxacts;
HeapTuple oldtuple, newtuple;
Oid src_tblspcoid, dst_tblspcoid;
Datum new_record[Natts_pg_database];
bool new_record_nulls[Natts_pg_database];
bool new_record_repl[Natts_pg_database];
ScanKeyData scankey;
SysScanDesc sysscan;
AclResult aclresult;
char* src_dbpath = NULL;
char* dst_dbpath = NULL;
DIR* dstdir = NULL;
struct dirent* xlde = NULL;
movedb_failure_params fparms;
/*
* Look up the target database's OID, and get exclusive lock on it. We
* need this to ensure that no new backend starts up in the database while
* we are moving it, and that no one is using it as a CREATE DATABASE
* template or trying to delete it.
*/
pgdbrel = heap_open(DatabaseRelationId, RowExclusiveLock);
if (!get_db_info(
dbname, AccessExclusiveLock, &db_id, NULL, NULL, NULL, NULL, NULL, NULL, &src_tblspcoid, NULL, NULL))
ereport(ERROR, (errcode(ERRCODE_UNDEFINED_DATABASE), errmsg("database \"%s\" does not exist", dbname)));
/*
* We actually need a session lock, so that the lock will persist across
* the commit/restart below. (We could almost get away with letting the
* lock be released at commit, except that someone could try to move
* relations of the DB back into the old directory while we rmtree() it.)
*/
LockSharedObjectForSession(DatabaseRelationId, db_id, 0, AccessExclusiveLock);
#ifdef PGXC
/*
* Now that we have session lock, transaction lock is not necessary.
* Besides, a PREPARE does not allow both transaction and session lock on the
* same object
*/
UnlockSharedObject(DatabaseRelationId, db_id, 0, AccessExclusiveLock);
#endif
/* Permission check. */
AlterDatabasePermissionCheck(db_id, dbname);
/*
* Obviously can't move the tables of my own database
*/
if (db_id == u_sess->proc_cxt.MyDatabaseId)
ereport(ERROR,
(errcode(ERRCODE_OBJECT_IN_USE), errmsg("cannot change the tablespace of the currently open database")));
/*
* Get tablespace's oid
*/
dst_tblspcoid = get_tablespace_oid(tblspcname, false);
/*
* Permission checks
*/
aclresult = pg_tablespace_aclcheck(dst_tblspcoid, GetUserId(), ACL_CREATE);
if (aclresult != ACLCHECK_OK)
aclcheck_error(aclresult, ACL_KIND_TABLESPACE, tblspcname);
/*
* pg_global must never be the default tablespace
*/
if (dst_tblspcoid == GLOBALTABLESPACE_OID)
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE), errmsg("pg_global cannot be used as default tablespace")));
/*
* No-op if same tablespace
*/
if (src_tblspcoid == dst_tblspcoid) {
heap_close(pgdbrel, NoLock);
UnlockSharedObjectForSession(DatabaseRelationId, db_id, 0, AccessExclusiveLock);
return;
}
/*
* Check for other backends in the target database. (Because we hold the
* database lock, no new ones can start after this.)
*
* As in CREATE DATABASE, check this after other error conditions.
*/
if (CountOtherDBBackends(db_id, &notherbackends, &npreparedxacts))
ereport(ERROR,
(errcode(ERRCODE_OBJECT_IN_USE),
errmsg("Database \"%s\" is being accessed by other users. You can stop all connections by command:"
" \"clean connection to all force for database XXXX;\" or wait for the sessions to end by querying "
"view: \"pg_stat_activity\".", dbname),
errdetail_busy_db(notherbackends, npreparedxacts)));
/*
* Get old and new database paths
*/
src_dbpath = GetDatabasePath(db_id, src_tblspcoid);
dst_dbpath = GetDatabasePath(db_id, dst_tblspcoid);
/*
* Force a checkpoint before proceeding. This will force dirty buffers out
* to disk, to ensure source database is up-to-date on disk for the copy.
* FlushDatabaseBuffers() would suffice for that, but we also want to
* process any pending unlink requests. Otherwise, the check for existing
* files in the target directory might fail unnecessarily, not to mention
* that the copy might fail due to source files getting deleted under it.
* On Windows, this also ensures that background procs don't hold any open
* files, which would cause rmdir() to fail.
*/
RequestCheckpoint(CHECKPOINT_IMMEDIATE | CHECKPOINT_FORCE | CHECKPOINT_WAIT);
/*
* Check for existence of files in the target directory, i.e., objects of
* this database that are already in the target tablespace. We can't
* allow the move in such a case, because we would need to change those
* relations' pg_class.reltablespace entries to zero, and we don't have
* access to the DB's pg_class to do so.
*/
dstdir = AllocateDir(dst_dbpath);
if (dstdir != NULL) {
while ((xlde = ReadDir(dstdir, dst_dbpath)) != NULL) {
if (strcmp(xlde->d_name, ".") == 0 || strcmp(xlde->d_name, "..") == 0)
continue;
ereport(ERROR,
(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
errmsg("some relations of database \"%s\" are already in tablespace \"%s\"", dbname, tblspcname),
errhint(
"You must move them back to the database's default tablespace before using this command.")));
}
FreeDir(dstdir);
/*
* The directory exists but is empty. We must remove it before using
* the copydir function.
*/
if (rmdir(dst_dbpath) != 0)
ereport(ERROR, (errcode(ERRCODE_IO_ERROR), errmsg("could not remove directory \"%s\": %m", dst_dbpath)));
}
/*
* Use an ENSURE block to make sure we remove the debris if the copy fails
* (eg, due to out-of-disk-space). This is not a 100% solution, because
* of the possibility of failure during transaction commit, but it should
* handle most scenarios.
*/
fparms.dest_dboid = db_id;
fparms.dest_tsoid = dst_tblspcoid;
PG_ENSURE_ERROR_CLEANUP(movedb_failure_callback, PointerGetDatum(&fparms));
{
/*
* Copy files from the old tablespace to the new one
*/
(void)copydir(src_dbpath, dst_dbpath, false, ERROR);
/*
* Record the filesystem change in XLOG
*/
{
xl_dbase_create_rec xlrec;
xlrec.db_id = db_id;
xlrec.tablespace_id = dst_tblspcoid;
xlrec.src_db_id = db_id;
xlrec.src_tablespace_id = src_tblspcoid;
XLogBeginInsert();
XLogRegisterData((char*)&xlrec, sizeof(xl_dbase_create_rec));
(void)XLogInsert(RM_DBASE_ID, XLOG_DBASE_CREATE | XLR_SPECIAL_REL_UPDATE);
}
/*
* Update the database's pg_database tuple
*/
ScanKeyInit(&scankey, Anum_pg_database_datname, BTEqualStrategyNumber, F_NAMEEQ, NameGetDatum(dbname));
sysscan = systable_beginscan(pgdbrel, DatabaseNameIndexId, true, NULL, 1, &scankey);
oldtuple = systable_getnext(sysscan);
if (!HeapTupleIsValid(oldtuple)) /* shouldn't happen... */
ereport(ERROR, (errcode(ERRCODE_UNDEFINED_DATABASE), errmsg("database \"%s\" does not exist", dbname)));
errno_t rc = EOK;
rc = memset_s(new_record, sizeof(new_record), 0, sizeof(new_record));
securec_check(rc, "\0", "\0");
rc = memset_s(new_record_nulls, sizeof(new_record_nulls), false, sizeof(new_record_nulls));
securec_check(rc, "\0", "\0");
rc = memset_s(new_record_repl, sizeof(new_record_repl), false, sizeof(new_record_repl));
securec_check(rc, "\0", "\0");
new_record[Anum_pg_database_dattablespace - 1] = ObjectIdGetDatum(dst_tblspcoid);
new_record_repl[Anum_pg_database_dattablespace - 1] = true;
newtuple =
(HeapTuple) tableam_tops_modify_tuple(oldtuple, RelationGetDescr(pgdbrel), new_record, new_record_nulls, new_record_repl);
simple_heap_update(pgdbrel, &oldtuple->t_self, newtuple);
/* Update indexes */
CatalogUpdateIndexes(pgdbrel, newtuple);
systable_endscan(sysscan);
/*
* Force another checkpoint here. As in CREATE DATABASE, this is to
* ensure that we don't have to replay a committed XLOG_DBASE_CREATE
* operation, which would cause us to lose any unlogged operations
* done in the new DB tablespace before the next checkpoint.
*/
RequestCheckpoint(CHECKPOINT_IMMEDIATE | CHECKPOINT_FORCE | CHECKPOINT_WAIT);
/*
* Force synchronous commit, thus minimizing the window between
* copying the database files and commital of the transaction. If we
* crash before committing, we'll leave an orphaned set of files on
* disk, which is not fatal but not good either.
*/
ForceSyncCommit();
/*
* Close pg_database, but keep lock till commit.
*/
heap_close(pgdbrel, NoLock);
}
PG_END_ENSURE_ERROR_CLEANUP(movedb_failure_callback, PointerGetDatum(&fparms));
#ifdef PGXC
/*
* Even if we are successful, ultimately this transaction may or may not
* be committed. so arrange for cleanup of source directory or target
* directory during commit or abort, respectively.
*/
fparms.src_tsoid = src_tblspcoid;
set_dbcleanup_callback(movedb_xact_callback, &fparms, sizeof(fparms));
}
/*
* movedb_success_callback:
* Cleanup files in the dbpath directory corresponding to db_id and tblspcoid.
* This function code is actual part of the movedb() operation in PG. We have
* made a function out of it for PGXC, and it gets called as part of the
* at-commit xact callback mechanism.
*/
static void movedb_success_callback(Oid db_id, Oid src_tblspcoid)
{
char* src_dbpath = GetDatabasePath(db_id, src_tblspcoid);
#endif /* PGXC */
/*
* Commit the transaction so that the pg_database update is committed. If
* we crash while removing files, the database won't be corrupt, we'll
* just leave some orphaned files in the old directory.
*
* (This is OK because we know we aren't inside a transaction block.)
*
* XXX would it be safe/better to do this inside the ensure block? Not
* convinced it's a good idea; consider elog just after the transaction
* really commits.
*/
#ifdef PGXC
/*
* Don't commit the transaction. We don't require the two separate
* commits since we handle this function as at-commit xact callback.
*/
#else
PopActiveSnapshot();
CommitTransactionCommand();
/* Start new transaction for the remaining work; don't need a snapshot */
StartTransactionCommand();
#endif
/*
* Remove files from the old tablespace
*/
if (!rmtree(src_dbpath, true))
ereport(
WARNING, (errmsg("some useless files may be left behind in old database directory \"%s\"", src_dbpath)));
/*
* Record the filesystem change in XLOG
*/
{
xl_dbase_drop_rec xlrec;
xlrec.db_id = db_id;
xlrec.tablespace_id = src_tblspcoid;
XLogBeginInsert();
XLogRegisterData((char*)&xlrec, sizeof(xl_dbase_drop_rec));
(void)XLogInsert(RM_DBASE_ID, XLOG_DBASE_DROP | XLR_SPECIAL_REL_UPDATE);
}
/* Now it's safe to release the database lock */
UnlockSharedObjectForSession(DatabaseRelationId, db_id, 0, AccessExclusiveLock);
#ifdef PGXC
pfree_ext(src_dbpath);
#endif
}
#ifdef PGXC
/*
* Error cleanup callback for movedb. Aftec movedb() succeeds, the
* transaction can still be aborted due to other nodes. So on abort-transaction,
* this function is called to do the cleanup of target tablespace directory,
* and on transaction commit, it is called to cleanup source directory.
*/
static void movedb_xact_callback(bool isCommit, const void* arg)
{
movedb_failure_params* fparms = (movedb_failure_params*)DatumGetPointer(arg);
if (isCommit)
movedb_success_callback(fparms->dest_dboid, fparms->src_tsoid);
else {
/* Call the same function that is used in ENSURE block for movedb() */
movedb_failure_callback(XACT_EVENT_ABORT, PointerGetDatum(arg));
}
}
#endif
/* Error cleanup callback for movedb */
static void movedb_failure_callback(int code, Datum arg)
{
movedb_failure_params* fparms = (movedb_failure_params*)DatumGetPointer(arg);
char* dstpath = NULL;
/* Get rid of anything we managed to copy to the target directory */
dstpath = GetDatabasePath(fparms->dest_dboid, fparms->dest_tsoid);
(void)rmtree(dstpath, true);
}
/*
* ALTER DATABASE name ...
*/
void AlterDatabase(AlterDatabaseStmt* stmt, bool isTopLevel)
{
Relation rel;
HeapTuple tuple, newtuple;
ScanKeyData scankey;
SysScanDesc scan;
ListCell* option = NULL;
int connlimit = -1;
DefElem* dconnlimit = NULL;
DefElem* dtablespace = NULL;
DefElem* privateobject = NULL;
Datum new_record[Natts_pg_database];
bool new_record_nulls[Natts_pg_database];
bool new_record_repl[Natts_pg_database];
/* Extract options from the statement node tree */
foreach (option, stmt->options) {
DefElem* defel = (DefElem*)lfirst(option);
if (strcmp(defel->defname, "connectionlimit") == 0) {
if (dconnlimit != NULL)
ereport(ERROR, (errcode(ERRCODE_SYNTAX_ERROR), errmsg("conflicting or redundant options")));
dconnlimit = defel;
} else if (strcmp(defel->defname, "tablespace") == 0) {
if (dtablespace != NULL)
ereport(ERROR, (errcode(ERRCODE_SYNTAX_ERROR), errmsg("conflicting or redundant options")));
dtablespace = defel;
} else if (strcmp(defel->defname, "privateobject") == 0) {
if (privateobject != NULL)
ereport(ERROR, (errcode(ERRCODE_SYNTAX_ERROR), errmsg("conflicting or redundant options")));
privateobject = defel;
} else
ereport(ERROR, (errcode(ERRCODE_SYNTAX_ERROR), errmsg("option \"%s\" not recognized", defel->defname)));
}
if (dtablespace != NULL) {
Oid dst_deftablespace = get_tablespace_oid(strVal(dtablespace->arg), false);
/* currently, can't be specified along with any other options */
Assert(!dconnlimit);
if (IsSpecifiedTblspc(dst_deftablespace, FILESYSTEM_HDFS)) {
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("DFS tablespace can not be used as default tablespace.")));
}
/* this case isn't allowed within a transaction block */
#ifdef PGXC
/* Clean connections before alter a database on local node */
if (IS_PGXC_COORDINATOR && !IsConnFromCoord()) {
/* clean all connections with dbname on all CNs before db operations */
PreCleanAndCheckConns(stmt->dbname, false);
}
/* ... but we allow it on remote nodes */
if (IS_PGXC_COORDINATOR && !IsConnFromCoord())
#endif
PreventTransactionChain(isTopLevel, "ALTER DATABASE SET TABLESPACE");
movedb(stmt->dbname, strVal(dtablespace->arg));
return;
}
if (dconnlimit != NULL) {
connlimit = intVal(dconnlimit->arg);
if (connlimit < -1)
ereport(
ERROR, (errcode(ERRCODE_INVALID_PARAMETER_VALUE), errmsg("invalid connection limit: %d", connlimit)));
}
/*
* Get the old tuple. We don't need a lock on the database per se,
* because we're not going to do anything that would mess up incoming
* connections.
*/
rel = heap_open(DatabaseRelationId, RowExclusiveLock);
ScanKeyInit(&scankey, Anum_pg_database_datname, BTEqualStrategyNumber, F_NAMEEQ, NameGetDatum(stmt->dbname));
scan = systable_beginscan(rel, DatabaseNameIndexId, true, NULL, 1, &scankey);
tuple = systable_getnext(scan);
if (!HeapTupleIsValid(tuple))
ereport(ERROR, (errcode(ERRCODE_UNDEFINED_DATABASE), errmsg("database \"%s\" does not exist", stmt->dbname)));
/* Permmision Check */
AlterDatabasePermissionCheck(HeapTupleGetOid(tuple), stmt->dbname);
/*
* Build an updated tuple, perusing the information just obtained
*/
errno_t rc = EOK;
rc = memset_s(new_record, sizeof(new_record), 0, sizeof(new_record));
securec_check(rc, "\0", "\0");
rc = memset_s(new_record_nulls, sizeof(new_record_nulls), false, sizeof(new_record_nulls));
securec_check(rc, "\0", "\0");
rc = memset_s(new_record_repl, sizeof(new_record_repl), false, sizeof(new_record_repl));
securec_check(rc, "\0", "\0");
if (dconnlimit != NULL) {
new_record[Anum_pg_database_datconnlimit - 1] = Int32GetDatum(connlimit);
new_record_repl[Anum_pg_database_datconnlimit - 1] = true;
}
if (privateobject != NULL) {
bool enablePrivateObject = (intVal(privateobject->arg) > 0);
Form_pg_database dbform = (Form_pg_database)GETSTRUCT(tuple);
AlterDatabasePrivateObject(dbform, HeapTupleGetOid(tuple), enablePrivateObject);
}
newtuple = (HeapTuple) tableam_tops_modify_tuple(tuple, RelationGetDescr(rel), new_record, new_record_nulls, new_record_repl);
simple_heap_update(rel, &tuple->t_self, newtuple);
/* Update indexes */
CatalogUpdateIndexes(rel, newtuple);
systable_endscan(scan);
/* Close pg_database, but keep lock till commit */
heap_close(rel, NoLock);
}
/*
* ALTER DATABASE name SET ...
*/
void AlterDatabaseSet(AlterDatabaseSetStmt* stmt)
{
Oid datid = get_database_oid(stmt->dbname, false);
/*
* Obtain a lock on the database and make sure it didn't go away in the
* meantime.
*/
shdepLockAndCheckObject(DatabaseRelationId, datid);
/* Permission check. */
AlterDatabasePermissionCheck(datid, stmt->dbname);
AlterSetting(datid, InvalidOid, stmt->setstmt);
#ifdef ENABLE_MULTIPLE_NODES
printHintInfo(stmt->dbname, NULL);
#endif
UnlockSharedObject(DatabaseRelationId, datid, 0, AccessShareLock);
}
/*
* ALTER DATABASE name OWNER TO newowner
*/
void AlterDatabaseOwner(const char* dbname, Oid newOwnerId)
{
HeapTuple tuple;
Relation rel;
ScanKeyData scankey;
SysScanDesc scan;
Form_pg_database datForm;
if (userbindlc(newOwnerId))
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE), errmsg("database cannot be owned by logic cluster user.")));
/*
* Get the old tuple. We don't need a lock on the database per se,
* because we're not going to do anything that would mess up incoming
* connections.
*/
rel = heap_open(DatabaseRelationId, RowExclusiveLock);
ScanKeyInit(&scankey, Anum_pg_database_datname, BTEqualStrategyNumber, F_NAMEEQ, NameGetDatum(dbname));
scan = systable_beginscan(rel, DatabaseNameIndexId, true, NULL, 1, &scankey);
tuple = systable_getnext(scan);
if (!HeapTupleIsValid(tuple))
ereport(ERROR, (errcode(ERRCODE_UNDEFINED_DATABASE), errmsg("database \"%s\" does not exist", dbname)));
datForm = (Form_pg_database)GETSTRUCT(tuple);
/*
* If the new owner is the same as the existing owner, consider the
* command to have succeeded. This is to be consistent with other
* objects.
*/
if (datForm->datdba != newOwnerId) {
Datum repl_val[Natts_pg_database];
bool repl_null[Natts_pg_database];
bool repl_repl[Natts_pg_database];
Acl* newAcl = NULL;
Datum aclDatum;
bool isNull = false;
HeapTuple newtuple;
errno_t rc;
/* Otherwise, must be owner of the existing object */
if (!pg_database_ownercheck(HeapTupleGetOid(tuple), GetUserId()))
aclcheck_error(ACLCHECK_NOT_OWNER, ACL_KIND_DATABASE, dbname);
/* Must be able to become new owner */
check_is_member_of_role(GetUserId(), newOwnerId);
/*
* must have createdb rights
*
* NOTE: This is different from other alter-owner checks in that the
* current user is checked for createdb privileges instead of the
* destination owner. This is consistent with the CREATE case for
* databases. Because superusers will always have this right, we need
* no special case for them.
*/
if (!have_createdb_privilege())
ereport(ERROR,
(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE), errmsg("permission denied to change owner of database")));
rc = memset_s(repl_null, sizeof(repl_null), false, sizeof(repl_null));
securec_check(rc, "\0", "\0");
rc = memset_s(repl_repl, sizeof(repl_repl), false, sizeof(repl_repl));
securec_check(rc, "\0", "\0");
repl_repl[Anum_pg_database_datdba - 1] = true;
repl_val[Anum_pg_database_datdba - 1] = ObjectIdGetDatum(newOwnerId);
/*
* Determine the modified ACL for the new owner. This is only
* necessary when the ACL is non-null.
*/
aclDatum = heap_getattr(tuple, Anum_pg_database_datacl, RelationGetDescr(rel), &isNull);
if (!isNull) {
newAcl = aclnewowner(DatumGetAclP(aclDatum), datForm->datdba, newOwnerId);
repl_repl[Anum_pg_database_datacl - 1] = true;
repl_val[Anum_pg_database_datacl - 1] = PointerGetDatum(newAcl);
}
newtuple = (HeapTuple) tableam_tops_modify_tuple(tuple, RelationGetDescr(rel), repl_val, repl_null, repl_repl);
simple_heap_update(rel, &newtuple->t_self, newtuple);
CatalogUpdateIndexes(rel, newtuple);
tableam_tops_free_tuple(newtuple);
/* Update owner dependency reference */
changeDependencyOnOwner(DatabaseRelationId, HeapTupleGetOid(tuple), newOwnerId);
}
systable_endscan(scan);
/* Close pg_database, but keep lock till commit */
heap_close(rel, NoLock);
}
/*
* Helper functions
*/
/*
* Look up info about the database named "name". If the database exists,
* obtain the specified lock type on it, fill in any of the remaining
* parameters that aren't NULL, and return TRUE. If no such database,
* return FALSE.
*/
static bool get_db_info(const char* name, LOCKMODE lockmode, Oid* dbIdP, Oid* ownerIdP, int* encodingP,
bool* dbIsTemplateP, bool* dbAllowConnP, Oid* dbLastSysOidP, TransactionId* dbFrozenXidP, Oid* dbTablespace,
char** dbCollate, char** dbCtype, char** dbcompatibility)
{
bool result = false;
Relation relation;
AssertArg(name);
/* Caller may wish to grab a better lock on pg_database beforehand... */
relation = heap_open(DatabaseRelationId, AccessShareLock);
/*
* Loop covers the rare case where the database is renamed before we can
* lock it. We try again just in case we can find a new one of the same
* name.
*/
for (;;) {
ScanKeyData scanKey;
SysScanDesc scan;
HeapTuple tuple;
Oid dbOid;
/*
* there's no syscache for database-indexed-by-name, so must do it the
* hard way
*/
ScanKeyInit(&scanKey, Anum_pg_database_datname, BTEqualStrategyNumber, F_NAMEEQ, NameGetDatum(name));
scan = systable_beginscan(relation, DatabaseNameIndexId, true, NULL, 1, &scanKey);
tuple = systable_getnext(scan);
if (!HeapTupleIsValid(tuple)) {
/* definitely no database of that name */
systable_endscan(scan);
break;
}
dbOid = HeapTupleGetOid(tuple);
systable_endscan(scan);
/*
* Now that we have a database OID, we can try to lock the DB.
*/
if (lockmode != NoLock)
LockSharedObject(DatabaseRelationId, dbOid, 0, lockmode);
/*
* And now, re-fetch the tuple by OID. If it's still there and still
* the same name, we win; else, drop the lock and loop back to try
* again.
*/
tuple = SearchSysCache1(DATABASEOID, ObjectIdGetDatum(dbOid));
if (HeapTupleIsValid(tuple)) {
Form_pg_database dbform = (Form_pg_database)GETSTRUCT(tuple);
if (strcmp(name, NameStr(dbform->datname)) == 0) {
/* oid of the database */
if (dbIdP != NULL)
*dbIdP = dbOid;
/* oid of the owner */
if (ownerIdP != NULL)
*ownerIdP = dbform->datdba;
/* character encoding */
if (encodingP != NULL)
*encodingP = dbform->encoding;
/* allowed as template? */
if (dbIsTemplateP != NULL)
*dbIsTemplateP = dbform->datistemplate;
/* allowing connections? */
if (dbAllowConnP != NULL)
*dbAllowConnP = dbform->datallowconn;
/* last system OID used in database */
if (dbLastSysOidP != NULL)
*dbLastSysOidP = dbform->datlastsysoid;
/* limit of frozen XIDs */
if (dbFrozenXidP != NULL) {
bool isNull = false;
TransactionId datfrozenxid;
Datum xid64datum =
heap_getattr(tuple, Anum_pg_database_datfrozenxid64, RelationGetDescr(relation), &isNull);
if (isNull) {
datfrozenxid = dbform->datfrozenxid;
if (TransactionIdPrecedes(t_thrd.xact_cxt.ShmemVariableCache->nextXid, datfrozenxid))
datfrozenxid = FirstNormalTransactionId;
} else {
datfrozenxid = DatumGetTransactionId(xid64datum);
}
*dbFrozenXidP = datfrozenxid;
}
/* default tablespace for this database */
if (dbTablespace != NULL)
*dbTablespace = dbform->dattablespace;
/* default locale settings for this database */
if (dbCollate != NULL)
*dbCollate = pstrdup(NameStr(dbform->datcollate));
if (dbCtype != NULL)
*dbCtype = pstrdup(NameStr(dbform->datctype));
if (dbcompatibility != NULL)
*dbcompatibility = pstrdup(NameStr(dbform->datcompatibility));
ReleaseSysCache(tuple);
result = true;
break;
}
/* can only get here if it was just renamed */
ReleaseSysCache(tuple);
}
if (lockmode != NoLock)
UnlockSharedObject(DatabaseRelationId, dbOid, 0, lockmode);
}
heap_close(relation, AccessShareLock);
return result;
}
/* Check if current user has createdb privileges */
bool have_createdb_privilege(void)
{
bool result = false;
HeapTuple utup;
/* Superusers can always do everything */
if (superuser())
return true;
utup = SearchSysCache1(AUTHOID, ObjectIdGetDatum(GetUserId()));
if (HeapTupleIsValid(utup)) {
result = ((Form_pg_authid)GETSTRUCT(utup))->rolcreatedb;
ReleaseSysCache(utup);
}
return result;
}
/*
* Remove tablespace directories
*
* We don't know what tablespaces db_id is using, so iterate through all
* tablespaces removing <tablespace>/db_id
*/
static void remove_dbtablespaces(Oid db_id)
{
Relation rel;
TableScanDesc scan;
HeapTuple tuple;
Snapshot snapshot;
/*
* As in createdb(), we'd better use an MVCC snapshot here, since this
* scan can run for a long time. Duplicate visits to tablespaces would be
* harmless, but missing a tablespace could result in permanently leaked
* files.
*
* XXX change this when a generic fix for SnapshotNow races is implemented
*/
snapshot = RegisterSnapshot(GetLatestSnapshot());
rel = heap_open(TableSpaceRelationId, AccessShareLock);
scan = tableam_scan_begin(rel, snapshot, 0, NULL);
while ((tuple = (HeapTuple) tableam_scan_getnexttuple(scan, ForwardScanDirection)) != NULL) {
Oid dsttablespace = HeapTupleGetOid(tuple);
char* dstpath = NULL;
struct stat st;
/* Don't mess with the global tablespace */
if (dsttablespace == GLOBALTABLESPACE_OID)
continue;
dstpath = GetDatabasePath(db_id, dsttablespace);
if (lstat(dstpath, &st) < 0 || !S_ISDIR(st.st_mode)) {
/* Assume we can ignore it */
pfree_ext(dstpath);
continue;
}
if (!rmtree(dstpath, true))
ereport(
WARNING, (errmsg("some useless files may be left behind in old database directory \"%s\"", dstpath)));
/* Record the filesystem change in XLOG */
{
xl_dbase_drop_rec xlrec;
xlrec.db_id = db_id;
xlrec.tablespace_id = dsttablespace;
XLogBeginInsert();
XLogRegisterData((char*)&xlrec, sizeof(xl_dbase_drop_rec));
(void)XLogInsert(RM_DBASE_ID, XLOG_DBASE_DROP | XLR_SPECIAL_REL_UPDATE);
}
pfree_ext(dstpath);
}
tableam_scan_end(scan);
heap_close(rel, AccessShareLock);
UnregisterSnapshot(snapshot);
}
/*
* Check for existing files that conflict with a proposed new DB OID;
* return TRUE if there are any
*
* If there were a subdirectory in any tablespace matching the proposed new
* OID, we'd get a create failure due to the duplicate name ... and then we'd
* try to remove that already-existing subdirectory during the cleanup in
* remove_dbtablespaces. Nuking existing files seems like a bad idea, so
* instead we make this extra check before settling on the OID of the new
* database. This exactly parallels what GetNewRelFileNode() does for table
* relfilenode values.
*/
static bool check_db_file_conflict(Oid db_id)
{
bool result = false;
Relation rel;
TableScanDesc scan;
HeapTuple tuple;
Snapshot snapshot;
/*
* As in createdb(), we'd better use an MVCC snapshot here; missing a
* tablespace could result in falsely reporting the OID is unique, with
* disastrous future consequences per the comment above.
*
* XXX change this when a generic fix for SnapshotNow races is implemented
*/
snapshot = RegisterSnapshot(GetLatestSnapshot());
rel = heap_open(TableSpaceRelationId, AccessShareLock);
scan = tableam_scan_begin(rel, snapshot, 0, NULL);
while ((tuple = (HeapTuple) tableam_scan_getnexttuple(scan, ForwardScanDirection)) != NULL) {
Oid dsttablespace = HeapTupleGetOid(tuple);
char* dstpath = NULL;
struct stat st;
/* Don't mess with the global tablespace */
if (dsttablespace == GLOBALTABLESPACE_OID)
continue;
dstpath = GetDatabasePath(db_id, dsttablespace);
if (lstat(dstpath, &st) == 0) {
/* Found a conflicting file (or directory, whatever) */
pfree_ext(dstpath);
result = true;
break;
}
pfree_ext(dstpath);
}
tableam_scan_end(scan);
heap_close(rel, AccessShareLock);
UnregisterSnapshot(snapshot);
return result;
}
/*
* Issue a suitable errdetail message for a busy database
*/
int errdetail_busy_db(int notherbackends, int npreparedxacts)
{
if (notherbackends > 0 && npreparedxacts > 0)
/* We don't deal with singular versus plural here, since gettext
* doesn't support multiple plurals in one string. */
errdetail("There are %d other session(s) and %d prepared transaction(s) using the database.",
notherbackends,
npreparedxacts);
else if (notherbackends > 0)
errdetail_plural("There is %d other session using the database.",
"There are %d other sessions using the database.",
notherbackends,
notherbackends);
else
errdetail_plural("There is %d prepared transaction using the database.",
"There are %d prepared transactions using the database.",
npreparedxacts,
npreparedxacts);
return 0; /* just to keep ereport macro happy */
}
/*
* get_database_oid - given a database name, look up the OID
*
* If missing_ok is false, throw an error if database name not found. If
* true, just return InvalidOid.
*/
Oid get_database_oid(const char* dbname, bool missing_ok)
{
Relation pg_database;
ScanKeyData entry[1];
SysScanDesc scan;
HeapTuple dbtuple;
Oid oid;
/*
* There's no syscache for pg_database indexed by name, so we must look
* the hard way.
*/
pg_database = heap_open(DatabaseRelationId, AccessShareLock);
ScanKeyInit(&entry[0], Anum_pg_database_datname, BTEqualStrategyNumber, F_NAMEEQ, CStringGetDatum(dbname));
scan = systable_beginscan(pg_database, DatabaseNameIndexId, true, NULL, 1, entry);
dbtuple = systable_getnext(scan);
/* We assume that there can be at most one matching tuple */
if (HeapTupleIsValid(dbtuple))
oid = HeapTupleGetOid(dbtuple);
else
oid = InvalidOid;
systable_endscan(scan);
heap_close(pg_database, AccessShareLock);
if (!OidIsValid(oid) && !missing_ok)
ereport(ERROR, (errcode(ERRCODE_UNDEFINED_DATABASE), errmsg("database \"%s\" does not exist", dbname)));
return oid;
}
/*
* get_database_name - given a database OID, look up the name
*
* Returns a palloc'd string, or NULL if no such database.
*/
char* get_database_name(Oid dbid)
{
HeapTuple dbtuple;
char* result = NULL;
dbtuple = SearchSysCache1(DATABASEOID, ObjectIdGetDatum(dbid));
if (HeapTupleIsValid(dbtuple)) {
result = pstrdup(NameStr(((Form_pg_database)GETSTRUCT(dbtuple))->datname));
ReleaseSysCache(dbtuple);
} else
result = NULL;
return result;
}
char* get_and_check_db_name(Oid dbid, bool is_ereport)
{
char* dbname = NULL;
dbname = get_database_name(dbid);
if (dbname == NULL) {
if (is_ereport) {
ereport(ERROR,
(errcode(ERRCODE_UNDEFINED_DATABASE),
errmsg("database with OID %u does not exist", dbid)));
}
dbname = pstrdup("invalid database");
}
return dbname;
}
/*
* DATABASE resource manager's routines
*/
void xlog_db_create(Oid dstDbId, Oid dstTbSpcId, Oid srcDbId, Oid srcTbSpcId)
{
char* src_path = NULL;
char* dst_path = NULL;
struct stat st;
src_path = GetDatabasePath(srcDbId, srcTbSpcId);
dst_path = GetDatabasePath(dstDbId, dstTbSpcId);
/*
* Our theory for replaying a CREATE is to forcibly drop the target
* subdirectory if present, then re-copy the source data. This may be
* more work than needed, but it is simple to implement.
*/
if (stat(dst_path, &st) == 0 && S_ISDIR(st.st_mode) && !IsRoachRestore()) {
if (!rmtree(dst_path, true))
/* If this failed, copydir() below is going to error. */
ereport(WARNING,
(errmsg("some useless files may be left behind in old database directory \"%s\"", dst_path)));
}
/*
* Force dirty buffers out to disk, to ensure source database is
* up-to-date for the copy.
*/
FlushDatabaseBuffers(srcDbId);
/*
* Copy this subdirectory to the new location
*
* We don't need to copy subdirectories
*/
bool copyRes = false;
copyRes = copydir(src_path, dst_path, false, WARNING);
/*
* In this scenario, src_path may be droped:
*
* #1. CHECKPOINT;
* #2. XLOG create db1 template db2;
* #3. XLOG drop db2;
* #4. Redo killed;
* #5. start again and Redo from #1, when Redo #2, src_path do not exits because it is already drop in Redo #3;
*/
if (!copyRes) {
RelFileNode tmp = {srcTbSpcId, srcDbId, 0, InvalidBktId};
/* forknum and blockno has no meaning */
log_invalid_page(tmp, MAIN_FORKNUM, 0, NOT_PRESENT);
}
}
void xlog_db_drop(Oid dbId, Oid tbSpcId)
{
char* dst_path = GetDatabasePath(dbId, tbSpcId);
if (InHotStandby) {
/*
* Lock database while we resolve conflicts to ensure that
* InitPostgres() cannot fully re-execute concurrently. This
* avoids backends re-connecting automatically to same database,
* which can happen in some cases.
*/
LockSharedObjectForSession(DatabaseRelationId, dbId, 0, AccessExclusiveLock);
ResolveRecoveryConflictWithDatabase(dbId);
}
/* Drop pages for this database that are in the shared buffer cache */
DropDatabaseBuffers(dbId);
/* Also, clean out any fsync requests that might be pending in md.c */
ForgetDatabaseFsyncRequests(dbId);
/* Clean out the xlog relcache too */
XLogDropDatabase(dbId);
/* And remove the physical files */
if (!rmtree(dst_path, true)) {
ereport(WARNING, (errmsg("some useless files may be left behind in old database directory \"%s\"", dst_path)));
}
if (InHotStandby) {
/*
* Release locks prior to commit. XXX There is a race condition
* here that may allow backends to reconnect, but the window for
* this is small because the gap between here and commit is mostly
* fairly small and it is unlikely that people will be dropping
* databases that we are trying to connect to anyway.
*/
UnlockSharedObjectForSession(DatabaseRelationId, dbId, 0, AccessExclusiveLock);
}
}
void dbase_redo(XLogReaderState* record)
{
uint8 info = XLogRecGetInfo(record) & ~XLR_INFO_MASK;
Assert(!XLogRecHasAnyBlockRefs(record));
if (info == XLOG_DBASE_CREATE) {
xl_dbase_create_rec* xlrec = (xl_dbase_create_rec*)XLogRecGetData(record);
xlog_db_create(xlrec->db_id, xlrec->tablespace_id, xlrec->src_db_id, xlrec->src_tablespace_id);
} else if (info == XLOG_DBASE_DROP) {
xl_dbase_drop_rec* xlrec = (xl_dbase_drop_rec*)XLogRecGetData(record);
xlog_db_drop(xlrec->db_id, xlrec->tablespace_id);
} else
ereport(PANIC, (errcode(ERRCODE_UNRECOGNIZED_NODE_TYPE), errmsg("dbase_redo: unknown op code %hhu", info)));
t_thrd.xlog_cxt.needImmediateCkp = true;
}
/*
* Get remote nodes prepared xacts, if remote nodes have prepared xacts,
* we cannot drop database. Otherwise, drop database finally failed in
* remote nodes and gs_clean cannot connect to database in CN to clean
* the in-doubt transactions.
* The memory palloc in PortalHeapMemory context, it will release after
* operation finished, it also can be released in abort transaction if operation
* failed.
*/
int64 GetRemoteNodePreparedNumDB(const char* dbname)
{
int64 size = 0;
StringInfoData buf;
ParallelFunctionState* state = NULL;
initStringInfo(&buf);
appendStringInfo(&buf,
"SELECT count(*) from pg_catalog.pg_prepared_xacts where database = '%s'", dbname);
state = RemoteFunctionResultHandler(buf.data, NULL, StrategyFuncSum, true, EXEC_ON_ALL_NODES, true);
size = state->result;
FreeParallelFunctionState(state);
return size;
}
/*
* the function is just called in 3 cases currently:
* 1. drop db, 2. rename db, 3. change tablespace of db
* There are step 1 and 2 in pgxc, it cann't check gsql session to remote CNs;
* There are step 1 and 4 in gaussdb before, it's appropriate just for 2 CNs,
* Think about the case below:
* cn1: cn2: cn3:
* create database db1
* create table t1 \c db1
* create table t2 \c db1
* create table t3
* There are 2 connections between every 2 CNs, so it is not enough for more
* than 2 CNs to run step 1 and 4 to clean connections in pooler on all CNs.
*/
void PreCleanAndCheckConns(const char* dbname, bool missing_ok)
{
char query[256];
int rc;
Oid db_id;
int notherbackends, npreparedxacts;
int64 nremotepreparedxacts;
/* 0. check if db exists? */
db_id = get_database_oid(dbname, missing_ok);
if (InvalidOid == db_id)
return; // just for drop database if exists dbname
/* 1. clean connections on local pooler */
DropDBCleanConnection((char*)dbname);
/* 2. clean connections on pooler of remote CNs */
rc = sprintf_s(query, sizeof(query), "CLEAN CONNECTION TO ALL FOR DATABASE %s;", quote_identifier(dbname));
securec_check_ss(rc, "\0", "\0");
ExecUtilityStmtOnNodes(query, NULL, false, true, EXEC_ON_COORDS, false);
/* 3. check for other backends in the local CN */
if (CountOtherDBBackends(db_id, &notherbackends, &npreparedxacts))
ereport(ERROR,
(errcode(ERRCODE_OBJECT_IN_USE),
errmsg("Database \"%s\" is being accessed by other users. You can stop all connections by command:"
" \"clean connection to all force for database XXXX;\" or wait for the sessions to end by querying "
"view: \"pg_stat_activity\".", dbname),
errdetail_busy_db(notherbackends, npreparedxacts)));
/* 4. check for other backends in remote CNs */
rc = sprintf_s(query, sizeof(query), "CLEAN CONNECTION TO ALL CHECK FOR DATABASE %s;", quote_identifier(dbname));
securec_check_ss(rc, "\0", "\0");
ExecUtilityStmtOnNodes(query, NULL, false, true, EXEC_ON_COORDS, false);
/* 5. get and check remote node prepared xacts num */
nremotepreparedxacts = GetRemoteNodePreparedNumDB(dbname);
if (nremotepreparedxacts != 0) {
ereport(ERROR,
(errcode(ERRCODE_OBJECT_IN_USE),
errmsg("Database \"%s\" is being accessed by other users. You can "
"call gs_clean to clean prepared transactions", dbname),
errdetail_busy_db(0, nremotepreparedxacts)));
}
}
/*
* AlterDatabasePrivateObject
* Alter database private object attribute
*
* @param (in) fbform: include all the information for database.
* @param (in) dbid: database id
* @param (in) enablePrivateObject: enable database private object or disable database private object
* @return: void
*/
static void AlterDatabasePrivateObject(const Form_pg_database fbform, Oid dbid, bool enablePrivateObject)
{
Assert(fbform != NULL);
/* Check whether need to change db private object on current node */
if (SupportRlsOnCurrentNode() == false) {
return;
}
/* Check license whether support this feature */
LicenseSupportRls();
if (dbid != u_sess->proc_cxt.MyDatabaseId) {
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("Not support alter cross-database private pbject, please switch to \"%s\" and run this command",
NameStr(fbform->datname))));
}
Relation rel = NULL;
Oid rlsPolicyId = InvalidOid;
/* Create row level security policy on system catalog */
if (enablePrivateObject) {
/*
* step 1: create row level security for pg_class if not exists
* CREATE ROW LEVEL SECURITY POLICY pg_class_rls ON pg_class AS PERMISSIVE FOR SELECT TO PUBLIC
* USING (has_table_privilege(current_user, oid, 'select'))
*/
rlsPolicyId = get_rlspolicy_oid(RelationRelationId, "pg_class_rls", true);
if (false == OidIsValid(rlsPolicyId)) {
CreateRlsPolicyForSystem("pg_catalog", "pg_class", "pg_class_rls", "has_table_privilege", "oid", "select");
rel = relation_open(RelationRelationId, ShareUpdateExclusiveLock);
ATExecEnableDisableRls(rel, RELATION_RLS_ENABLE, ShareUpdateExclusiveLock);
relation_close(rel, ShareUpdateExclusiveLock);
}
/*
* step 2: create row level security for pg_attribute if not exists
* CREATE ROW LEVEL SECURITY POLICY pg_attribute_rls ON pg_attribute AS PERMISSIVE FOR SELECT TO PUBLIC
* USING (has_table_privilege(current_user, attrelid, 'select'))
*/
rlsPolicyId = get_rlspolicy_oid(AttributeRelationId, "pg_attribute_rls", true);
if (false == OidIsValid(rlsPolicyId)) {
CreateRlsPolicyForSystem(
"pg_catalog", "pg_attribute", "pg_attribute_rls", "has_table_privilege", "attrelid", "select");
rel = relation_open(AttributeRelationId, ShareUpdateExclusiveLock);
ATExecEnableDisableRls(rel, RELATION_RLS_ENABLE, ShareUpdateExclusiveLock);
relation_close(rel, ShareUpdateExclusiveLock);
}
/*
* step 3: create row level security for pg_proc if not exists
* CREATE ROW LEVEL SECURITY POLICY pg_proc_rls ON pg_proc AS PERMISSIVE FOR SELECT TO PUBLIC
* USING (has_function_privilege(current_user, oid, 'select'))
*/
rlsPolicyId = get_rlspolicy_oid(ProcedureRelationId, "pg_proc_rls", true);
if (false == OidIsValid(rlsPolicyId)) {
CreateRlsPolicyForSystem(
"pg_catalog", "pg_proc", "pg_proc_rls", "has_function_privilege", "oid", "execute");
rel = relation_open(ProcedureRelationId, ShareUpdateExclusiveLock);
ATExecEnableDisableRls(rel, RELATION_RLS_ENABLE, ShareUpdateExclusiveLock);
relation_close(rel, ShareUpdateExclusiveLock);
}
/*
* step 4: create row level security for pg_namespace if not exists
* CREATE ROW LEVEL SECURITY POLICY pg_namespace_rls ON pg_namespace AS PERMISSIVE FOR SELECT TO PUBLIC
* USING (has_schema_privilege(current_user, nspname, 'select'))
*/
rlsPolicyId = get_rlspolicy_oid(NamespaceRelationId, "pg_namespace_rls", true);
if (false == OidIsValid(rlsPolicyId)) {
CreateRlsPolicyForSystem(
"pg_catalog", "pg_namespace", "pg_namespace_rls", "has_schema_privilege", "oid", "USAGE");
rel = relation_open(NamespaceRelationId, ShareUpdateExclusiveLock);
ATExecEnableDisableRls(rel, RELATION_RLS_ENABLE, ShareUpdateExclusiveLock);
relation_close(rel, ShareUpdateExclusiveLock);
}
/*
* step 5: create row level security for pgxc_slice if not exists
* CREATE ROW LEVEL SECURITY POLICY pgxc_slice_rls ON pgxc_slice AS PERMISSIVE FOR SELECT TO PUBLIC
* USING (has_schema_privilege(current_user, nspname, 'select'))
*/
if (t_thrd.proc->workingVersionNum >= RANGE_LIST_DISTRIBUTION_VERSION_NUM) {
rlsPolicyId = get_rlspolicy_oid(PgxcSliceRelationId, "pgxc_slice_rls", true);
if (OidIsValid(rlsPolicyId) == false) {
CreateRlsPolicyForSystem(
"pg_catalog", "pgxc_slice", "pgxc_slice_rls", "has_table_privilege", "relid", "select");
rel = relation_open(PgxcSliceRelationId, ShareUpdateExclusiveLock);
ATExecEnableDisableRls(rel, RELATION_RLS_ENABLE, ShareUpdateExclusiveLock);
relation_close(rel, ShareUpdateExclusiveLock);
}
}
/*
* step 6: create row level security for pg_partition if not exists
* CREATE ROW LEVEL SECURITY POLICY pg_partition_rls ON pg_partition AS PERMISSIVE FOR SELECT TO PUBLIC
* USING (has_schema_privilege(current_user, nspname, 'select'))
*/
rlsPolicyId = get_rlspolicy_oid(PartitionRelationId, "pg_partition_rls", true);
if (OidIsValid(rlsPolicyId) == false) {
CreateRlsPolicyForSystem(
"pg_catalog", "pg_partition", "pg_partition_rls", "has_table_privilege", "parentid", "select");
rel = relation_open(PartitionRelationId, ShareUpdateExclusiveLock);
ATExecEnableDisableRls(rel, RELATION_RLS_ENABLE, ShareUpdateExclusiveLock);
relation_close(rel, ShareUpdateExclusiveLock);
}
} else {
/* Remove row level security policy for system catalog */
/* step 1: remove row level security policy from pg_class */
rlsPolicyId = get_rlspolicy_oid(RelationRelationId, "pg_class_rls", true);
if (OidIsValid(rlsPolicyId)) {
RemoveRlsPolicyById(rlsPolicyId);
rel = relation_open(RelationRelationId, ShareUpdateExclusiveLock);
ATExecEnableDisableRls(rel, RELATION_RLS_DISABLE, ShareUpdateExclusiveLock);
relation_close(rel, ShareUpdateExclusiveLock);
}
/* step 2: remove row level security policy from pg_attribute */
rlsPolicyId = get_rlspolicy_oid(AttributeRelationId, "pg_attribute_rls", true);
if (OidIsValid(rlsPolicyId)) {
RemoveRlsPolicyById(rlsPolicyId);
rel = relation_open(AttributeRelationId, ShareUpdateExclusiveLock);
ATExecEnableDisableRls(rel, RELATION_RLS_DISABLE, ShareUpdateExclusiveLock);
relation_close(rel, ShareUpdateExclusiveLock);
}
/* step 3: remove row level security policy from pg_proc */
rlsPolicyId = get_rlspolicy_oid(ProcedureRelationId, "pg_proc_rls", true);
if (OidIsValid(rlsPolicyId)) {
RemoveRlsPolicyById(rlsPolicyId);
rel = relation_open(ProcedureRelationId, ShareUpdateExclusiveLock);
ATExecEnableDisableRls(rel, RELATION_RLS_DISABLE, ShareUpdateExclusiveLock);
relation_close(rel, ShareUpdateExclusiveLock);
}
/* step 4: remove row level security policy from pg_namespace */
rlsPolicyId = get_rlspolicy_oid(NamespaceRelationId, "pg_namespace_rls", true);
if (OidIsValid(rlsPolicyId)) {
RemoveRlsPolicyById(rlsPolicyId);
rel = relation_open(NamespaceRelationId, ShareUpdateExclusiveLock);
ATExecEnableDisableRls(rel, RELATION_RLS_DISABLE, ShareUpdateExclusiveLock);
relation_close(rel, ShareUpdateExclusiveLock);
}
/* step 5: remove row level security policy from pgxc_slice */
if (t_thrd.proc->workingVersionNum >= RANGE_LIST_DISTRIBUTION_VERSION_NUM) {
rlsPolicyId = get_rlspolicy_oid(PgxcSliceRelationId, "pgxc_slice_rls", true);
if (OidIsValid(rlsPolicyId)) {
RemoveRlsPolicyById(rlsPolicyId);
rel = relation_open(PgxcSliceRelationId, ShareUpdateExclusiveLock);
ATExecEnableDisableRls(rel, RELATION_RLS_DISABLE, ShareUpdateExclusiveLock);
relation_close(rel, ShareUpdateExclusiveLock);
}
}
/* step 6: remove row level security policy from pg_partition */
rlsPolicyId = get_rlspolicy_oid(PartitionRelationId, "pg_partition_rls", true);
if (OidIsValid(rlsPolicyId)) {
RemoveRlsPolicyById(rlsPolicyId);
rel = relation_open(PartitionRelationId, ShareUpdateExclusiveLock);
ATExecEnableDisableRls(rel, RELATION_RLS_DISABLE, ShareUpdateExclusiveLock);
relation_close(rel, ShareUpdateExclusiveLock);
}
}
}
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