r3704: Implement a cache get saves the result of a pdb_getsampwnam for later

retrieval by pdb_getsampwsid. This solves our problem that we do lots of calls
to LDAP during a typical XP login. XP does a lookupnames, then an openuser and
some queryinfo stuff. Lookupnames triggers the initial getsampwnam, and all
the subsequent ones make us call getsampwsid. This patch gets this down to one
call to LDAP.

Yes, a more "correct" way would be to stick the information to the open user
handle, but this one is simpler and saves the LDAP roundtrip for the openuser
call.

Volker
(This used to be commit 3d9758fa3c584bb25eca0b7ed04af4ddfeba315f)

1 files changed, 27 insertions, 1 deletions

diff --git a/source3/passdb/pdb_interface.c b/source3/passdb/pdb_interface.c
index 5747435e69..082e57ecc0 100644
--- a/source3/passdb/pdb_interface.c
+++ b/source3/passdb/pdb_interface.c
@@ -871,6 +871,8 @@ BOOL pdb_getsampwent(SAM_ACCOUNT *user)
 	return NT_STATUS_IS_OK(pdb_context->pdb_getsampwent(pdb_context, user));
 }
 
+static SAM_ACCOUNT *sam_account_cache = NULL;
+
 BOOL pdb_getsampwnam(SAM_ACCOUNT *sam_acct, const char *username) 
 {
 	struct pdb_context *pdb_context = pdb_get_static_context(False);
@@ -879,7 +881,17 @@ BOOL pdb_getsampwnam(SAM_ACCOUNT *sam_acct, const char *username)
 		return False;
 	}
 
-	return NT_STATUS_IS_OK(pdb_context->pdb_getsampwnam(pdb_context, sam_acct, username));
+	if (!NT_STATUS_IS_OK(pdb_context->pdb_getsampwnam(pdb_context,
+							  sam_acct, username)))
+		return False;
+
+	if (sam_account_cache != NULL) {
+		pdb_free_sam(&sam_account_cache);
+		sam_account_cache = NULL;
+	}
+
+	pdb_copy_sam_account(sam_acct, &sam_account_cache);
+	return True;
 }
 
 BOOL pdb_getsampwsid(SAM_ACCOUNT *sam_acct, const DOM_SID *sid) 
@@ -890,6 +902,10 @@ BOOL pdb_getsampwsid(SAM_ACCOUNT *sam_acct, const DOM_SID *sid)
 		return False;
 	}
 
+	if ((sam_account_cache != NULL) &&
+	    (sid_equal(sid, pdb_get_user_sid(sam_account_cache))))
+		return pdb_copy_sam_account(sam_account_cache, &sam_acct);
+
 	return NT_STATUS_IS_OK(pdb_context->pdb_getsampwsid(pdb_context, sam_acct, sid));
 }
 
@@ -912,6 +928,11 @@ BOOL pdb_update_sam_account(SAM_ACCOUNT *sam_acct)
 		return False;
 	}
 
+	if (sam_account_cache != NULL) {
+		pdb_free_sam(&sam_account_cache);
+		sam_account_cache = NULL;
+	}
+
 	return NT_STATUS_IS_OK(pdb_context->pdb_update_sam_account(pdb_context, sam_acct));
 }
 
@@ -923,6 +944,11 @@ BOOL pdb_delete_sam_account(SAM_ACCOUNT *sam_acct)
 		return False;
 	}
 
+	if (sam_account_cache != NULL) {
+		pdb_free_sam(&sam_account_cache);
+		sam_account_cache = NULL;
+	}
+
 	return NT_STATUS_IS_OK(pdb_context->pdb_delete_sam_account(pdb_context, sam_acct));
 }