From dbeba43bd33ce41bc3c5c95615176e59eb76f00c Mon Sep 17 00:00:00 2001
From: Neil Brown <neilb@suse.de>
Date: Thu, 11 Jan 2007 12:51:29 +1100
Subject: [PATCH] Ensure 'showmount -e' gets current information.

If auth_reload has been called by someone else, get_exportlist
can incorrectly return old data.  So track modify times better
and only use cached data if the modify time matches.
---
 utils/mountd/auth.c   | 6 +++---
 utils/mountd/mountd.c | 7 ++++++-
 utils/mountd/mountd.h | 2 +-
 3 files changed, 10 insertions(+), 5 deletions(-)

diff --git a/utils/mountd/auth.c b/utils/mountd/auth.c
index 4f803d7..183c9ea 100644
--- a/utils/mountd/auth.c
+++ b/utils/mountd/auth.c
@@ -46,7 +46,7 @@ auth_init(char *exports)
 	xtab_mount_write();
 }
 
-int
+time_t
 auth_reload()
 {
 	struct stat		stb;
@@ -55,7 +55,7 @@ auth_reload()
 	if (stat(_PATH_ETAB, &stb) < 0)
 		xlog(L_FATAL, "couldn't stat %s", _PATH_ETAB);
 	if (stb.st_mtime == last_modified)
-		return 0;
+		return last_modified;
 	last_modified = stb.st_mtime;
 
 	export_freeall();
@@ -63,7 +63,7 @@ auth_reload()
 	// export_read(export_file);
 	xtab_export_read();
 
-	return 1;
+	return last_modified;
 }
 
 static nfs_export *
diff --git a/utils/mountd/mountd.c b/utils/mountd/mountd.c
index 72332ce..5204faa 100644
--- a/utils/mountd/mountd.c
+++ b/utils/mountd/mountd.c
@@ -463,14 +463,19 @@ static exports
 get_exportlist(void)
 {
 	static exports		elist = NULL;
+	static time_t		etime = 0;
+	time_t			atime;
 	struct exportnode	*e, *ne;
 	struct groupnode	*g, *ng, *c, **cp;
 	nfs_export		*exp;
 	int			i;
 
-	if (!auth_reload() && elist)
+	atime = auth_reload();
+	if (elist && atime == etime)
 		return elist;
 
+	etime = atime;
+
 	for (e = elist; e != NULL; e = ne) {
 		ne = e->ex_next;
 		for (g = e->ex_groups; g != NULL; g = ng) {
diff --git a/utils/mountd/mountd.h b/utils/mountd/mountd.h
index d64c171..b539278 100644
--- a/utils/mountd/mountd.h
+++ b/utils/mountd/mountd.h
@@ -40,7 +40,7 @@ bool_t		mount_mnt_3_svc(struct svc_req *, dirpath *, mountres3 *);
 
 void		mount_dispatch(struct svc_req *, SVCXPRT *);
 void		auth_init(char *export_file);
-int		auth_reload(void);
+time_t		auth_reload(void);
 nfs_export *	auth_authenticate(char *what, struct sockaddr_in *sin,
 					char *path);
 void		auth_export(nfs_export *exp);
-- 
2.39.2