From 1012492bc0bfb322d59db17e17735d17d634e264 Mon Sep 17 00:00:00 2001
From: Greg Stark <stark@mit.edu>
Date: Sun, 14 Feb 2010 17:50:52 +0000
Subject: [PATCH] Make CREATE DATABASE safe against losing whole files by
fsyncing the directory and not just the individual files.
Back-patch to 8.1 -- before that we just called "cp -r" and never
fsynced anything anyways.
---
src/port/copydir.c | 23 ++++++++++++++++++++++-
1 file changed, 22 insertions(+), 1 deletion(-)
diff --git a/src/port/copydir.c b/src/port/copydir.c
index 1b5c3262646..0bf764ecffc 100644
--- a/src/port/copydir.c
+++ b/src/port/copydir.c
@@ -11,7 +11,7 @@
* as a service.
*
* IDENTIFICATION
- * $PostgreSQL: pgsql/src/port/copydir.c,v 1.24 2010/01/02 16:58:13 momjian Exp $
+ * $PostgreSQL: pgsql/src/port/copydir.c,v 1.25 2010/02/14 17:50:52 stark Exp $
*
*-------------------------------------------------------------------------
*/
@@ -50,6 +50,7 @@ copydir(char *fromdir, char *todir, bool recurse)
{
DIR *xldir;
struct dirent *xlde;
+ int dirfd;
char fromfile[MAXPGPATH];
char tofile[MAXPGPATH];
@@ -91,6 +92,26 @@ copydir(char *fromdir, char *todir, bool recurse)
}
FreeDir(xldir);
+
+ /*
+ * fsync the directory to make sure not just the data but also the
+ * new directory file entries have reached the disk. While needed
+ * by most filesystems, the window got bigger with newer ones like
+ * ext4.
+ */
+ dirfd = BasicOpenFile(todir,
+ O_RDONLY | PG_BINARY,
+ S_IRUSR | S_IWUSR);
+ if(dirfd == -1)
+ ereport(ERROR,
+ (errcode_for_file_access(),
+ errmsg("could not open directory for fsync \"%s\": %m", todir)));
+
+ if(pg_fsync(dirfd) == -1)
+ ereport(ERROR,
+ (errcode_for_file_access(),
+ errmsg("could not fsync directory \"%s\": %m", todir)));
+ close(dirfd);
}
/*
--
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