1 files changed, 165 insertions, 214 deletions

diff --git a/src/backend/commands/dbcommands.c b/src/backend/commands/dbcommands.c
index 295ae955d1f..01b53e06933 100644
--- a/src/backend/commands/dbcommands.c
+++ b/src/backend/commands/dbcommands.c
@@ -15,7 +15,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/commands/dbcommands.c,v 1.168 2005/07/31 17:19:17 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/commands/dbcommands.c,v 1.169 2005/08/02 19:02:31 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -79,14 +79,14 @@ createdb(const CreatedbStmt *stmt)
 	TransactionId src_vacuumxid;
 	TransactionId src_frozenxid;
 	Oid			src_deftablespace;
-	Oid			dst_deftablespace;
-	Relation	pg_database_rel;
+	volatile Oid dst_deftablespace;
+	volatile Relation pg_database_rel = NULL;
 	HeapTuple	tuple;
 	TupleDesc	pg_database_dsc;
 	Datum		new_record[Natts_pg_database];
 	char		new_record_nulls[Natts_pg_database];
 	Oid			dboid;
-	Oid			datdba;
+	volatile Oid datdba;
 	ListCell   *option;
 	DefElem    *dtablespacename = NULL;
 	DefElem    *downer = NULL;
@@ -96,12 +96,8 @@ createdb(const CreatedbStmt *stmt)
 	char	   *dbname = stmt->dbname;
 	char	   *dbowner = NULL;
 	const char *dbtemplate = NULL;
-	int			encoding = -1;
-	int			dbconnlimit = -1;
-
-#ifndef WIN32
-	char		buf[2 * MAXPGPATH + 100];
-#endif
+	volatile int encoding = -1;
+	volatile int dbconnlimit = -1;
 
 	/* don't call this in a transaction block */
 	PreventTransactionChain((void *) stmt, "CREATE DATABASE");
@@ -363,207 +359,186 @@ createdb(const CreatedbStmt *stmt)
 	BufferSync();
 
 	/*
-	 * Close virtual file descriptors so the kernel has more available for
-	 * the system() calls below.
+	 * Once we start copying subdirectories, we need to be able to clean
+	 * 'em up if we fail.  Establish a TRY 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.)
 	 */
-	closeAllVfds();
-
-	/*
-	 * Iterate through all tablespaces of the template database, and copy
-	 * each one to the new database.
-	 */
-	rel = heap_open(TableSpaceRelationId, AccessShareLock);
-	scan = heap_beginscan(rel, SnapshotNow, 0, NULL);
-	while ((tuple = heap_getnext(scan, ForwardScanDirection)) != NULL)
+	PG_TRY();
 	{
-		Oid			srctablespace = HeapTupleGetOid(tuple);
-		Oid			dsttablespace;
-		char	   *srcpath;
-		char	   *dstpath;
-		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))
+		/*
+		 * Iterate through all tablespaces of the template database,
+		 * and copy each one to the new database.
+		 */
+		rel = heap_open(TableSpaceRelationId, AccessShareLock);
+		scan = heap_beginscan(rel, SnapshotNow, 0, NULL);
+		while ((tuple = heap_getnext(scan, ForwardScanDirection)) != NULL)
 		{
-			/* Assume we can ignore it */
-			pfree(srcpath);
-			continue;
-		}
-
-		if (srctablespace == src_deftablespace)
-			dsttablespace = dst_deftablespace;
-		else
-			dsttablespace = srctablespace;
-
-		dstpath = GetDatabasePath(dboid, dsttablespace);
+			Oid			srctablespace = HeapTupleGetOid(tuple);
+			Oid			dsttablespace;
+			char	   *srcpath;
+			char	   *dstpath;
+			struct stat st;
 
-		if (stat(dstpath, &st) == 0 || errno != ENOENT)
-		{
-			remove_dbtablespaces(dboid);
-			ereport(ERROR,
-					(errmsg("could not initialize database directory"),
-					 errdetail("Directory \"%s\" already exists.",
-							   dstpath)));
+			/* 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(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
+			 */
+			copydir(srcpath, dstpath, false);
+
+			/* Record the filesystem change in XLOG */
+			{
+				xl_dbase_create_rec xlrec;
+				XLogRecData rdata[1];
+
+				xlrec.db_id = dboid;
+				xlrec.tablespace_id = dsttablespace;
+				xlrec.src_db_id = src_dboid;
+				xlrec.src_tablespace_id = srctablespace;
+
+				rdata[0].data = (char *) &xlrec;
+				rdata[0].len = sizeof(xl_dbase_create_rec);
+				rdata[0].buffer = InvalidBuffer;
+				rdata[0].next = NULL;
+
+				(void) XLogInsert(RM_DBASE_ID, XLOG_DBASE_CREATE, rdata);
+			}
 		}
-
-#ifndef WIN32
+		heap_endscan(scan);
+		heap_close(rel, AccessShareLock);
 
 		/*
-		 * Copy this subdirectory to the new location
-		 *
-		 * XXX use of cp really makes this code pretty grotty, particularly
-		 * with respect to lack of ability to report errors well.  Someday
-		 * rewrite to do it for ourselves.
+		 * Now OK to grab exclusive lock on pg_database.
 		 */
+		pg_database_rel = heap_open(DatabaseRelationId, ExclusiveLock);
 
-		/* We might need to use cp -R one day for portability */
-		snprintf(buf, sizeof(buf), "cp -r '%s' '%s'",
-				 srcpath, dstpath);
-		if (system(buf) != 0)
-		{
-			remove_dbtablespaces(dboid);
-			ereport(ERROR,
-					(errmsg("could not initialize database directory"),
-					 errdetail("Failing system command was: %s", buf),
-					 errhint("Look in the postmaster's stderr log for more information.")));
-		}
-#else							/* WIN32 */
-		if (copydir(srcpath, dstpath) != 0)
-		{
-			/* copydir should already have given details of its troubles */
-			remove_dbtablespaces(dboid);
+		/* Check to see if someone else created same DB name meanwhile. */
+		if (get_db_info(dbname, NULL, NULL, NULL,
+						NULL, NULL, NULL, NULL, NULL, NULL))
 			ereport(ERROR,
-					(errmsg("could not initialize database directory")));
-		}
-#endif   /* WIN32 */
-
-		/* Record the filesystem change in XLOG */
-		{
-			xl_dbase_create_rec xlrec;
-			XLogRecData rdata[1];
-
-			xlrec.db_id = dboid;
-			xlrec.tablespace_id = dsttablespace;
-			xlrec.src_db_id = src_dboid;
-			xlrec.src_tablespace_id = srctablespace;
+					(errcode(ERRCODE_DUPLICATE_DATABASE),
+					 errmsg("database \"%s\" already exists", dbname)));
 
-			rdata[0].data = (char *) &xlrec;
-			rdata[0].len = sizeof(xl_dbase_create_rec);
-			rdata[0].buffer = InvalidBuffer;
-			rdata[0].next = NULL;
-
-			(void) XLogInsert(RM_DBASE_ID, XLOG_DBASE_CREATE, rdata);
-		}
-	}
-	heap_endscan(scan);
-	heap_close(rel, AccessShareLock);
-
-	/*
-	 * Now OK to grab exclusive lock on pg_database.
-	 */
-	pg_database_rel = heap_open(DatabaseRelationId, ExclusiveLock);
+		/*
+		 * Insert a new tuple into pg_database
+		 */
+		pg_database_dsc = RelationGetDescr(pg_database_rel);
+
+		/* Form tuple */
+		MemSet(new_record, 0, sizeof(new_record));
+		MemSet(new_record_nulls, ' ', sizeof(new_record_nulls));
+
+		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_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_datvacuumxid - 1] = TransactionIdGetDatum(src_vacuumxid);
+		new_record[Anum_pg_database_datfrozenxid - 1] = TransactionIdGetDatum(src_frozenxid);
+		new_record[Anum_pg_database_dattablespace - 1] = ObjectIdGetDatum(dst_deftablespace);
 
-	/* Check to see if someone else created same DB name meanwhile. */
-	if (get_db_info(dbname, NULL, NULL, NULL,
-					NULL, NULL, NULL, NULL, NULL, NULL))
-	{
-		/* Don't hold lock while doing recursive remove */
-		heap_close(pg_database_rel, ExclusiveLock);
-		remove_dbtablespaces(dboid);
-		ereport(ERROR,
-				(errcode(ERRCODE_DUPLICATE_DATABASE),
-				 errmsg("database \"%s\" already exists", dbname)));
-	}
+		/*
+		 * We deliberately set datconfig and datacl to defaults (NULL), rather
+		 * than copying them from the template database.  Copying datacl would
+		 * be a bad idea when the owner is not the same as the template's
+		 * owner. It's more debatable whether datconfig should be copied.
+		 */
+		new_record_nulls[Anum_pg_database_datconfig - 1] = 'n';
+		new_record_nulls[Anum_pg_database_datacl - 1] = 'n';
 
-	/*
-	 * Insert a new tuple into pg_database
-	 */
-	pg_database_dsc = RelationGetDescr(pg_database_rel);
+		tuple = heap_formtuple(pg_database_dsc, new_record, new_record_nulls);
 
-	/* Form tuple */
-	MemSet(new_record, 0, sizeof(new_record));
-	MemSet(new_record_nulls, ' ', sizeof(new_record_nulls));
+		HeapTupleSetOid(tuple, dboid);		/* override heap_insert's OID
+											 * selection */
 
-	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_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_datvacuumxid - 1] = TransactionIdGetDatum(src_vacuumxid);
-	new_record[Anum_pg_database_datfrozenxid - 1] = TransactionIdGetDatum(src_frozenxid);
-	new_record[Anum_pg_database_dattablespace - 1] = ObjectIdGetDatum(dst_deftablespace);
+		simple_heap_insert(pg_database_rel, tuple);
 
-	/*
-	 * We deliberately set datconfig and datacl to defaults (NULL), rather
-	 * than copying them from the template database.  Copying datacl would
-	 * be a bad idea when the owner is not the same as the template's
-	 * owner. It's more debatable whether datconfig should be copied.
-	 */
-	new_record_nulls[Anum_pg_database_datconfig - 1] = 'n';
-	new_record_nulls[Anum_pg_database_datacl - 1] = 'n';
+		/* Update indexes */
+		CatalogUpdateIndexes(pg_database_rel, tuple);
 
-	tuple = heap_formtuple(pg_database_dsc, new_record, new_record_nulls);
+		/* Register owner dependency */
+		recordDependencyOnOwner(DatabaseRelationId, dboid, datdba);
 
-	HeapTupleSetOid(tuple, dboid);		/* override heap_insert's OID
-										 * selection */
+		/* Create pg_shdepend entries for objects within database */
+		copyTemplateDependencies(src_dboid, dboid);
 
-	simple_heap_insert(pg_database_rel, tuple);
+		/*
+		 * 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(true, false);
 
-	/* Update indexes */
-	CatalogUpdateIndexes(pg_database_rel, tuple);
+		/*
+		 * Set flag to update flat database file at commit.
+		 */
+		database_file_update_needed();
+	}
+	PG_CATCH();
+	{
+		/* Don't hold pg_database lock while doing recursive remove */
+		if (pg_database_rel != NULL)
+			heap_close(pg_database_rel, ExclusiveLock);
 
-	/* Register owner dependency */
-	recordDependencyOnOwner(DatabaseRelationId, dboid, datdba);
+		/* Throw away any successfully copied subdirectories */
+		remove_dbtablespaces(dboid);
 
-	/* Create pg_shdepend entries for objects within database */
-	copyTemplateDependencies(src_dboid, dboid);
+		PG_RE_THROW();
+	}
+	PG_END_TRY();
 
 	/* Close pg_database, but keep exclusive lock till commit */
+	/* This has to be outside the PG_TRY */
 	heap_close(pg_database_rel, NoLock);
-
-	/*
-	 * 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(true, false);
-
-	/*
-	 * Set flag to update flat database file at commit.
-	 */
-	database_file_update_needed();
 }
 
 
@@ -1348,10 +1323,6 @@ dbase_redo(XLogRecPtr lsn, XLogRecord *record)
 		char	   *dst_path;
 		struct stat st;
 
-#ifndef WIN32
-		char		buf[2 * MAXPGPATH + 100];
-#endif
-
 		src_path = GetDatabasePath(xlrec->src_db_id, xlrec->src_tablespace_id);
 		dst_path = GetDatabasePath(xlrec->db_id, xlrec->tablespace_id);
 
@@ -1365,8 +1336,8 @@ dbase_redo(XLogRecPtr lsn, XLogRecord *record)
 		{
 			if (!rmtree(dst_path, true))
 				ereport(WARNING,
-					(errmsg("could not remove database directory \"%s\"",
-							dst_path)));
+						(errmsg("could not remove database directory \"%s\"",
+								dst_path)));
 		}
 
 		/*
@@ -1376,32 +1347,12 @@ dbase_redo(XLogRecPtr lsn, XLogRecord *record)
 		 */
 		BufferSync();
 
-#ifndef WIN32
-
 		/*
 		 * Copy this subdirectory to the new location
 		 *
-		 * XXX use of cp really makes this code pretty grotty, particularly
-		 * with respect to lack of ability to report errors well.  Someday
-		 * rewrite to do it for ourselves.
+		 * We don't need to copy subdirectories
 		 */
-
-		/* We might need to use cp -R one day for portability */
-		snprintf(buf, sizeof(buf), "cp -r '%s' '%s'",
-				 src_path, dst_path);
-		if (system(buf) != 0)
-			ereport(ERROR,
-					(errmsg("could not initialize database directory"),
-					 errdetail("Failing system command was: %s", buf),
-					 errhint("Look in the postmaster's stderr log for more information.")));
-#else							/* WIN32 */
-		if (copydir(src_path, dst_path) != 0)
-		{
-			/* copydir should already have given details of its troubles */
-			ereport(ERROR,
-					(errmsg("could not initialize database directory")));
-		}
-#endif   /* WIN32 */
+		copydir(src_path, dst_path, false);
 	}
 	else if (info == XLOG_DBASE_DROP)
 	{