dsdb-schema: do not reload more often than schema_reload_interval

Samba 4 use to try to reload the schema every time dsdb_get_schema was
called (which could be 20+ time per ldb request). Now we only reload at
most every xx seconds (xx being the value of dsdb:"schema_reload_interval"
 or 120). The timestamp of the last reloaded schema is kept in the
 dsdb_schema object. There is also a timestamp in the ldb_context, that
 is used by the LDAP server to know if it has to reload the schema after
 handling the request. This is used to allow that the schema will be
 immediately reload after a schemaUpdateNow request has been issued, the
 reload can't occur in the handling of the LDAP request itself because
 we have a transaction autostarted.

1 files changed, 23 insertions, 2 deletions

diff --git a/source4/ldap_server/ldap_backend.c b/source4/ldap_server/ldap_backend.c
index afeb3500d0f..000d7e28f81 100644
--- a/source4/ldap_server/ldap_backend.c
+++ b/source4/ldap_server/ldap_backend.c
@@ -1162,6 +1162,9 @@ NTSTATUS ldapsrv_do_call(struct ldapsrv_call *call)
 {
 	unsigned int i;
 	struct ldap_message *msg = call->request;
+	struct ldb_context *samdb = call->conn->ldb;
+	NTSTATUS status;
+	time_t *lastts;
 	/* Check for undecoded critical extensions */
 	for (i=0; msg->controls && msg->controls[i]; i++) {
 		if (!msg->controls_decoded[i] && 
@@ -1180,9 +1183,11 @@ NTSTATUS ldapsrv_do_call(struct ldapsrv_call *call)
 	case LDAP_TAG_SearchRequest:
 		return ldapsrv_SearchRequest(call);
 	case LDAP_TAG_ModifyRequest:
-		return ldapsrv_ModifyRequest(call);
+		status = ldapsrv_ModifyRequest(call);
+		break;
 	case LDAP_TAG_AddRequest:
-		return ldapsrv_AddRequest(call);
+		status = ldapsrv_AddRequest(call);
+		break;
 	case LDAP_TAG_DelRequest:
 		return ldapsrv_DelRequest(call);
 	case LDAP_TAG_ModifyDNRequest:
@@ -1196,4 +1201,20 @@ NTSTATUS ldapsrv_do_call(struct ldapsrv_call *call)
 	default:
 		return ldapsrv_unwilling(call, LDAP_PROTOCOL_ERROR);
 	}
+
+	if (NT_STATUS_IS_OK(status)) {
+		lastts = (time_t *)ldb_get_opaque(samdb, DSDB_OPAQUE_LAST_SCHEMA_UPDATE_MSG_OPAQUE_NAME);
+		if (lastts && !*lastts) {
+			DEBUG(10, ("Schema update now was requested, fullfilling the request ts = %d\n", lastts));
+			/*
+			* Just requesting the schema will do the trick
+			* as the delay for reload is experied, we will have a reload
+			* from the schema as expected as we are not yet in a transaction!
+			*/
+			dsdb_get_schema(samdb, NULL);
+			*lastts = time(NULL);
+			ldb_set_opaque(samdb, DSDB_OPAQUE_LAST_SCHEMA_UPDATE_MSG_OPAQUE_NAME, lastts);
+		}
+	}
+	return status;
 }