Notice of disconnection
by Lars Hesel Christensen XX (AH/LMD)
Hi all
I've been looking at the Notice of disconnection handling in OpenLDAP
and there is a thing that is confusing me a bit.
in result.c, the function try_read1msg reads data from socket and
creates a new message from that. If we receive an unsolicited message,
e.g, notice of disconnection, then the msgId will be zero, and we will
go through the following code(taken from /* $OpenLDAP:
/libraries/libldap/result.c,v 1.144 2006/12/17 21:04:25 ando Exp $ */):
/* message id */
if ( ber_get_int( ber, &id ) == LBER_ERROR ) {
ber_free( ber, 1 );
ld->ld_errno = LDAP_DECODING_ERROR;
return( -1 );
}
/* if it's been abandoned, toss it */
if ( ldap_abandoned( ld, id, &idx ) ) {
<REMOVED since the msgId is not abandoned>
retry_ber:
ber_free( ber, 1 );
if ( ber_sockbuf_ctrl( lc->lconn_sb,
LBER_SB_OPT_DATA_READY, NULL ) ) {
goto retry;
}
--> return( LDAP_MSG_X_KEEP_LOOKING ); /* continue
looking */
}
lr = ldap_find_request_by_msgid( ld, id );
if ( lr == NULL ) {
const char *msg = "unknown";
/* the message type */
tag = ber_peek_tag( ber, &len );
switch ( tag ) {
case LBER_ERROR:
break;
default:
msg = ldap_int_msgtype2str( tag );
break;
}
Debug( LDAP_DEBUG_ANY,
"no request for response on ld %p msgid %ld
message type %s (tossing)\n",
(void *)ld, (long)id, msg );
goto retry_ber;
}
Assuming there is no more data to be read from the socket we will return
in the line marked with the arrow '-->' since
ldap_find_request_by_msgid() returns NULL.
What confuses me is that later on in try_read1msg we get to (after
constructing the message:
/* is this the one we're looking for? */
if ( msgid == LDAP_RES_ANY || id == msgid ) {
if ( all == LDAP_MSG_ONE
|| ( newmsg->lm_msgtype !=
LDAP_RES_SEARCH_RESULT
&& newmsg->lm_msgtype !=
LDAP_RES_SEARCH_ENTRY
&& newmsg->lm_msgtype !=
LDAP_RES_SEARCH_REFERENCE ) )
{
*result = newmsg;
ld->ld_errno = LDAP_SUCCESS;
return( tag );
} else if ( newmsg->lm_msgtype ==
LDAP_RES_SEARCH_RESULT) {
foundit = 1; /* return the chain later */
}
}
Do we have a test case testing notice of disconnection? I tried to grep
the 'tests' directory for 'notice', 'disconnection' and 'unsolicited'
but nothing came up.
Perhaps I'm misunderstanding something here, so if I am I would very
much appreciate a hint.
Happy newyear everyone,
Lars Hesel Christensen
--
Lars Hesel Christensen
Ericsson Denmark A/S, Telebit
lars.hesel.xx.christensen(a)ericsson.com
