RE: invalid data in file backup_label problem on windows

Wang, Shenhao <wangsh.fnst@cn.fujitsu.com>

From: "Wang, Shenhao" <wangsh.fnst@cn.fujitsu.com>
To: "pgsql-hackers@lists.postgresql.org" <pgsql-hackers@lists.postgresql.org>
Date: 2021-01-15T03:29:57Z
Lists: pgsql-hackers
Hi, again:

On windows, if a backup_label file contains a windows(CRLF) line ending.
Recovering from this backup will failed.

I think this is a problem, can I add this to commitfest?

Best Regards,
Shenhao Wang

-----Original Message-----
From: Wang, Shenhao <wangsh.fnst@cn.fujitsu.com> 
Sent: Sunday, January 10, 2021 8:58 PM
To: pgsql-hackers@lists.postgresql.org
Subject: invalid data in file backup_label problem on windows

Hi hackers.

When I using a Non-Exclusive Low-Level Backup on windows, "invalid data in file backup_label" will be shown.

The code are listed below

	if (fscanf(lfp, "START WAL LOCATION: %X/%X (file %08X%16s)%c",
			   &hi, &lo, &tli_from_walseg, startxlogfilename, &ch) != 5 || ch != '\n')
		ereport(FATAL,
				(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
				 errmsg("invalid data in file \"%s\"", BACKUP_LABEL_FILE)));

When I wrote the backup_label on windows, CRLF will at the end of line, so the ch will be '\r'. 

I'm not sure that these two files(tablespace_map and backup_label) should not use CRLF new line style is mentioned in manual[1].
How about setting the text mode when reading these 2 files like patch listed in attachment?

Any thought?

[1] https://www.postgresql.org/docs/13/continuous-archiving.html#BACKUP-LOWLEVEL-BASE-BACKUP


Best Regards,
Shenhao Wang









Commits

  1. doc: Clarify how to generate backup files with non-exclusive backups