From 2f5c4397c39dea49c5608ba583868e26d767fc32 Mon Sep 17 00:00:00 2001 From: Robert Haas Date: Fri, 29 Oct 2021 14:00:32 -0400 Subject: [PATCH] When fetching WAL for a basebackup, report errors with a sensible TLI. The previous code used ThisTimeLineID, which need not even be initialized here, although it usually was in practice, because pg_basebackup issues IDENTIFY_SYSTEM before calling BASE_BACKUP, and that initializes ThisTimeLineID as a side effect. That's not really good enough, though, not only because we shoudn't be counting on side effects like that, but also because the TLI could change meanwhile. Fortunately, we have convenient access to more meaningful TLI values, so use those instead. Because of the way this logic is coded, the consequences of using a possibly-incorrect TLI here are no worse than a slightly confusing error message, I don't want to take any risk here, so no back-patch at least for now. Patch by me, reviewed by Kyotaro Horiguchi and Michael Paquier Discussion: http://postgr.es/m/CA+TgmoZRNWGWYDX9RgTXMG6_nwSdB=PB-PPRUbvMUTGfmL2sHQ@mail.gmail.com --- src/backend/replication/basebackup.c | 13 ++++++------- 1 file changed, 6 insertions(+), 7 deletions(-) diff --git a/src/backend/replication/basebackup.c b/src/backend/replication/basebackup.c index b31c36d918c..b7359f43903 100644 --- a/src/backend/replication/basebackup.c +++ b/src/backend/replication/basebackup.c @@ -502,9 +502,9 @@ perform_base_backup(basebackup_options *opt) * including them. */ XLByteToSeg(startptr, startsegno, wal_segment_size); - XLogFileName(firstoff, ThisTimeLineID, startsegno, wal_segment_size); + XLogFileName(firstoff, starttli, startsegno, wal_segment_size); XLByteToPrevSeg(endptr, endsegno, wal_segment_size); - XLogFileName(lastoff, ThisTimeLineID, endsegno, wal_segment_size); + XLogFileName(lastoff, endtli, endsegno, wal_segment_size); dir = AllocateDir("pg_wal"); while ((de = ReadDir(dir, "pg_wal")) != NULL) @@ -528,7 +528,7 @@ perform_base_backup(basebackup_options *opt) * Before we go any further, check that none of the WAL segments we * need were removed. */ - CheckXLogRemoved(startsegno, ThisTimeLineID); + CheckXLogRemoved(startsegno, starttli); /* * Sort the WAL filenames. We want to send the files in order from @@ -555,7 +555,7 @@ perform_base_backup(basebackup_options *opt) { char startfname[MAXFNAMELEN]; - XLogFileName(startfname, ThisTimeLineID, startsegno, + XLogFileName(startfname, starttli, startsegno, wal_segment_size); ereport(ERROR, (errmsg("could not find WAL file \"%s\"", startfname))); @@ -571,8 +571,7 @@ perform_base_backup(basebackup_options *opt) { char nextfname[MAXFNAMELEN]; - XLogFileName(nextfname, ThisTimeLineID, nextsegno, - wal_segment_size); + XLogFileName(nextfname, tli, nextsegno, wal_segment_size); ereport(ERROR, (errmsg("could not find WAL file \"%s\"", nextfname))); } @@ -581,7 +580,7 @@ perform_base_backup(basebackup_options *opt) { char endfname[MAXFNAMELEN]; - XLogFileName(endfname, ThisTimeLineID, endsegno, wal_segment_size); + XLogFileName(endfname, endtli, endsegno, wal_segment_size); ereport(ERROR, (errmsg("could not find WAL file \"%s\"", endfname))); }