tdbs in cache_dir or state_dir

[Christof Schmitt]

On Thu, Aug 18, 2016 at 02:07:14PM +0200, Stefan Metzmacher wrote:
> Hi Christof,
> 
> basically lock_path() is for CLEAR_IF_FIRST files,
> 
> cache_path() is on persistent storage but can safely deleted
> by the admin. And state_path() is for real persistent data.
> 
> winbindd_cache.tdb is only in state_path() because of the
> "winbind offline logon" option. otherwise is could be
> in lock_path() as it's CLEAR_IF_FIRST.
> 
> metze

Thanks you. I think that should be added to the documentation, see the
attached patches to clarify the entries in the smb.conf manpage and
adding a comment in the code.

Christof
-------------- next part --------------
From 960a96c33dc68b2a7232621c1acde798427e3225 Mon Sep 17 00:00:00 2001
From: Christof Schmitt <cs at samba.org>
Date: Thu, 18 Aug 2016 13:46:52 -0700
Subject: [PATCH 1/2] docs: Clarify description for cache, lock and state
 directory settings

Signed-off-by: Christof Schmitt <cs at samba.org>
---
 docs-xml/smbdotconf/misc/cachedirectory.xml | 7 +++++--
 docs-xml/smbdotconf/misc/lockdirectory.xml  | 4 ++++
 docs-xml/smbdotconf/misc/statedirectory.xml | 2 +-
 3 files changed, 10 insertions(+), 3 deletions(-)

diff --git a/docs-xml/smbdotconf/misc/cachedirectory.xml b/docs-xml/smbdotconf/misc/cachedirectory.xml
index 6ffda0b..21d7d94 100644
--- a/docs-xml/smbdotconf/misc/cachedirectory.xml
+++ b/docs-xml/smbdotconf/misc/cachedirectory.xml
@@ -12,8 +12,11 @@
 	<parameter moreinfo="none">cache directory</parameter> options.
 	</para>
 
-	<para> This option specifies the directory where TDB files containing
-	non-persistent data will be stored.
+	<para>This option specifies the directory for storing TDB
+	files containing non-persistent data that will be kept across
+	service restarts. The directory should be placed on persistent
+	storage, but the data can be safely deleted by an
+	administrator.
 	</para>
 </description>
 
diff --git a/docs-xml/smbdotconf/misc/lockdirectory.xml b/docs-xml/smbdotconf/misc/lockdirectory.xml
index 738de2e..3e58052 100644
--- a/docs-xml/smbdotconf/misc/lockdirectory.xml
+++ b/docs-xml/smbdotconf/misc/lockdirectory.xml
@@ -14,6 +14,10 @@
 		Note: This option can not be set inside registry
 		configurations.
 	</para>
+	<para>The files placed in this directory are not required
+	across service restarts and can be safely placed in volatile
+	storage (e.g. tmpfs in Linux)</para>
+	
 </description>
 
 <value type="default">&pathconfig.LOCKDIR;</value>
diff --git a/docs-xml/smbdotconf/misc/statedirectory.xml b/docs-xml/smbdotconf/misc/statedirectory.xml
index 084f145..2f2b064 100644
--- a/docs-xml/smbdotconf/misc/statedirectory.xml
+++ b/docs-xml/smbdotconf/misc/statedirectory.xml
@@ -13,7 +13,7 @@
 	</para>
 
 	<para> This option specifies the directory where TDB files containing
-	persistent data will be stored.
+	important persistent data will be stored.
 	</para>
 </description>
 
-- 
1.8.3.1


From 0e3ebfdd2b63c2582e69c19251d5bab4cb8e5f00 Mon Sep 17 00:00:00 2001
From: Christof Schmitt <cs at samba.org>
Date: Thu, 18 Aug 2016 14:01:50 -0700
Subject: [PATCH 2/2] winbindd: Introduce helper function for
 winbindd_cache.tdb directory

Also add a comment why the file is placed in the state directory.

Signed-off-by: Christof Schmitt <cs at samba.org>
---
 source3/winbindd/winbindd_cache.c | 19 ++++++++++++++-----
 1 file changed, 14 insertions(+), 5 deletions(-)

diff --git a/source3/winbindd/winbindd_cache.c b/source3/winbindd/winbindd_cache.c
index b2c0ae2..b921b75 100644
--- a/source3/winbindd/winbindd_cache.c
+++ b/source3/winbindd/winbindd_cache.c
@@ -111,6 +111,15 @@ void (*smb_panic_fn)(const char *const why) = smb_panic;
 
 static struct winbind_cache *wcache;
 
+static char *wcache_path(void)
+{
+	/*
+	 * Data needs to be kept persistent in state directory for
+	 * running with "winbindd offline logon".
+	 */
+	return state_path("winbindd_cache.tdb");
+}
+
 /* get the winbind_cache structure */
 static struct winbind_cache *get_cache(struct winbindd_domain *domain)
 {
@@ -3195,7 +3204,7 @@ bool init_wcache(void)
 	if (wcache->tdb != NULL)
 		return true;
 
-	db_path = state_path("winbindd_cache.tdb");
+	db_path = wcache_path();
 	if (db_path == NULL) {
 		return false;
 	}
@@ -3247,7 +3256,7 @@ bool initialize_winbindd_cache(void)
 		tdb_close(wcache->tdb);
 		wcache->tdb = NULL;
 
-		db_path = state_path("winbindd_cache.tdb");
+		db_path = wcache_path();
 		if (db_path == NULL) {
 			return false;
 		}
@@ -3384,7 +3393,7 @@ void wcache_flush_cache(void)
 		return;
 	}
 
-	db_path = state_path("winbindd_cache.tdb");
+	db_path = wcache_path();
 	if (db_path == NULL) {
 		return;
 	}
@@ -4281,7 +4290,7 @@ int winbindd_validate_cache(void)
 	DEBUG(10, ("winbindd_validate_cache: replacing panic function\n"));
 	smb_panic_fn = validate_panic;
 
-	tdb_path = state_path("winbindd_cache.tdb");
+	tdb_path = wcache_path();
 	if (tdb_path == NULL) {
 		goto done;
 	}
@@ -4352,7 +4361,7 @@ int winbindd_validate_cache_nobackup(void)
 	DEBUG(10, ("winbindd_validate_cache: replacing panic function\n"));
 	smb_panic_fn = validate_panic;
 
-	tdb_path = state_path("winbindd_cache.tdb");
+	tdb_path = wcache_path();
 	if (tdb_path == NULL) {
 		goto err_panic_restore;
 	}
-- 
1.8.3.1