From: Michael Paquier <michael@paquier.xyz>
Date: Wed, 9 Oct 2019 04:30:43 +0000 (+0900)
Subject: Flush logical mapping files with fd opened for read/write at checkpoint
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=b8e19b932a99a7eb5a3bce84e74b0b7c093d0981;p=postgresql

Flush logical mapping files with fd opened for read/write at checkpoint

The file descriptor was opened with read-only to fsync a regular file,
which would cause EBADFD errors on some platforms.

This is similar to the recent fix done by a586cc4b (which was broken by
me with 82a5649), except that I noticed this issue while monitoring the
backend code for similar mistakes.  Backpatch to 9.4, as this has been
introduced since logical decoding exists as of b89e151.

Author: Michael Paquier
Reviewed-by: Andres Freund
Discussion: https://postgr.es/m/20191006045548.GA14532@paquier.xyz
Backpatch-through: 9.4
---

diff --git a/src/backend/access/heap/rewriteheap.c b/src/backend/access/heap/rewriteheap.c
index 7c98a42b8b..306e74ea10 100644
--- a/src/backend/access/heap/rewriteheap.c
+++ b/src/backend/access/heap/rewriteheap.c
@@ -1280,7 +1280,8 @@ CheckPointLogicalRewriteHeap(void)
 		}
 		else
 		{
-			int			fd = OpenTransientFile(path, O_RDONLY | PG_BINARY);
+			/* on some operating systems fsyncing a file requires O_RDWR */
+			int			fd = OpenTransientFile(path, O_RDWR | PG_BINARY);
 
 			/*
 			 * The file cannot vanish due to concurrency since this function