static void tr_trps_cleanup_trpc(TRPS_INSTANCE *trps, TRPC_INSTANCE *trpc)
{
- TR_MQ_MSG *msg;
-
- /* tell the trpc thread to exit */
- msg = tr_mq_msg_new(NULL, TR_MQMSG_TRPC_EXIT_OK, TR_MQ_PRIO_NORMAL);
- if (msg) {
- tr_debug("tr_trps_cleanup_trpc: Notifying thread that it may now exit");
- trpc_mq_add(trpc, msg);
- } else {
- tr_crit("tr_trps_cleanup_trpc: Unable to acknowledge disconnection, thread will probably never terminate");
- }
-
pthread_join(*trp_connection_get_thread(trpc_get_conn(trpc)), NULL);
trps_remove_trpc(trps, trpc);
trpc_free(trpc);
tr_err("tr_trps_process_mq: incoming connection from unknown peer (%s) reported.", tmp);
else {
trp_peer_set_incoming_status(peer, PEER_CONNECTED);
- tr_err("tr_trps_process_mq: incoming connection from %s established.", tmp);
+ tr_notice("tr_trps_process_mq: incoming connection from %s established.", tmp);
}
free(tmp);
}
} else {
trp_peer_set_incoming_status(peer, PEER_DISCONNECTED);
tr_trps_cleanup_conn(trps, conn);
- tr_err("tr_trps_process_mq: incoming connection from %s lost.", tmp);
+ tr_notice("tr_trps_process_mq: incoming connection from %s lost.", tmp);
}
free(tmp);
}
tr_err("tr_trps_process_mq: outgoing connection to unknown peer (%s) reported.", tmp);
else {
trp_peer_set_outgoing_status(peer, PEER_CONNECTED);
- tr_err("tr_trps_process_mq: outgoing connection to %s established.", tmp);
+ tr_notice("tr_trps_process_mq: outgoing connection to %s established.", tmp);
}
free(tmp);
}
else if (0==strcmp(s, TR_MQMSG_TRPC_DISCONNECTED)) {
- /* The trpc connection died - see note above tr_trpc_thread() regarding the shutdown protocol.
- * The EXIT_OK message is sent in tr_trps_cleanup_trpc(). */
TRPC_INSTANCE *trpc=talloc_get_type_abort(tr_mq_msg_get_payload(msg), TRPC_INSTANCE);
TR_NAME *svcname=trpc_get_gssname(trpc);
peer=trps_get_peer_by_servicename(trps, svcname);
tr_err("tr_trps_process_mq: outgoing connection to unknown peer (%s) lost.", tmp);
else {
trp_peer_set_outgoing_status(peer, PEER_DISCONNECTED);
- tr_err("tr_trps_process_mq: outgoing connection to %s lost.", tmp);
+ tr_notice("tr_trps_process_mq: outgoing connection to %s lost.", tmp);
tr_trps_cleanup_trpc(trps, trpc);
}
free(tmp);
return retval;
}
-
-struct trpc_notify_cb_data {
- int msg_ready;
- pthread_cond_t cond;
- pthread_mutex_t mutex;
-};
-
-static void tr_trpc_mq_cb(TR_MQ *mq, void *arg)
-{
- struct trpc_notify_cb_data *cb_data=(struct trpc_notify_cb_data *) arg;
- pthread_mutex_lock(&(cb_data->mutex));
- if (!cb_data->msg_ready) {
- cb_data->msg_ready=1;
- pthread_cond_signal(&(cb_data->cond));
- }
- pthread_mutex_unlock(&(cb_data->mutex));
-}
-
/* data passed to thread */
struct trpc_thread_data {
TRPC_INSTANCE *trpc;
};
/**
- * Returns when a message is ready
- */
-static void trpc_thread_wait_for_message(struct trpc_notify_cb_data *cb)
-{
- cb->msg_ready = 0;
- do
- pthread_cond_wait(&(cb->cond), &(cb->mutex));
- while (!cb->msg_ready);
-}
-
-/**
* Thread for handling TRPC (outgoing) connections
*
- * Locking protocol:
- *
- * This thread uses a mutex and condition variable to wait for incoming messages
- * on its queue. The main thread interacts with these through the tr_trpc_mq_cb()
- * callback. This callback is called by the TR_MQ whenever the queue goes from empty
- * to non-empty. The callback locks the thread's mutex, then sets a msg_ready flag
- * signals the condition variable, then unlocks the mutex.
- *
- * This thread waits for the condition variable to be signaled, then checks that the
- * msg_ready flag has actually been set (pthreads does not guarantee against false
- * wakes). If so, it holds the mutex lock while reading any messages in its queue and
- * sending responses over the GSS connection. If it receives an ABORT message from
- * the main thread (not currently used), or if sending the GSS message fails (which
- * usually indicates that the connection has been lost), the thread begins the shutdown
- * process. It still holds the mutex lock at the start of this process.
- *
- * This begins by setting trpc->shutting_down = 1, then sending a message to the
- * TRPS (main) thread indicating that it has DISCONNECTED. It then releases the mutex
- * and waits for more messages, again using the mutex and the condition variable. It
- * ignores any except for an EXIT_OK message. When that is received, it exits, terminating
- * the thread.
- *
- * When the main thread receives the DISCONNECTED message, it must stop sending messages
- * to this thread's message queue. When it is certain that it will not queue any more messages,
- * it sends the EXIT_OK message as its last interaction with this thread. Once that message
- * has been queued, queueing additional messages may result in deadlock or segfaults.
- * (It is ok if there are other messages in the queue, but it must not queue more.)
+ * Opens a connection to a peer. If successful, notifies the trps thread by
+ * posting a TR_MQMSG_TRPC_CONNECTED message to the trps message queue.
+ * It then waits for messages on trpc->mq. Normally these will be TR_MQMSG_TRPC_SEND
+ * messages, which this thread forwards to the peer. If its connection is lost or
+ * a TR_MQMSG_ABORT message is received on trpc->mq, the thread sends a
+ * TR_MQMSG_TRPC_DISCONNECTED message to the trps thread, then cleans up and
+ * terminates.
*/
static void *tr_trpc_thread(void *arg)
{
const char *msg_type=NULL;
char *encoded_msg=NULL;
TR_NAME *peer_gssname=NULL;
- int n_sent = 0;
- int n_popped = 0;
+ struct timespec wait_until = {0};
int exit_loop=0;
- struct trpc_notify_cb_data cb_data={0,
- PTHREAD_COND_INITIALIZER,
- PTHREAD_MUTEX_INITIALIZER};
-
tr_debug("tr_trpc_thread: started");
- /* set up the mq for receiving */
- pthread_mutex_lock(&(cb_data.mutex)); /* hold this lock until we enter the main loop */
-
- tr_mq_lock(trpc->mq);
- tr_mq_set_notify_cb(trpc->mq, tr_trpc_mq_cb, (void *) &cb_data);
- tr_mq_unlock(trpc->mq);
-
+ /* Try to make the outgoing connection */
rc=trpc_connect(trpc);
if (rc!=TRP_SUCCESS) {
tr_notice("tr_trpc_thread: failed to initiate connection to %s:%d.",
trpc_get_server(trpc),
trpc_get_port(trpc));
} else {
+ /* Retrieve the GSS name used by the peer for authentication */
peer_gssname=trp_connection_get_peer(trpc_get_conn(trpc));
if (peer_gssname==NULL) {
tr_err("tr_trpc_thread: could not duplicate peer_gssname.");
talloc_free(tmp_ctx);
return NULL;
}
- tr_debug("tr_trpc_thread: connected to peer %s", peer_gssname->buf);
+ tr_debug("tr_trpc_thread: connected to peer %.*s",
+ peer_gssname->len, peer_gssname->buf);
msg=tr_mq_msg_new(tmp_ctx, TR_MQMSG_TRPC_CONNECTED, TR_MQ_PRIO_HIGH);
tr_mq_msg_set_payload(msg, (void *)tr_dup_name(peer_gssname), tr_free_name_helper);
trps_mq_add(trps, msg); /* steals msg context */
msg=NULL;
+ /* Loop until we get an abort message or until the connection is lost. */
while(!exit_loop) {
- trpc_thread_wait_for_message(&cb_data); /* handles locking */
-
- n_popped = 0; /* have not popped any messages from the queue */
- n_sent = 0; /* have not sent any messages yet */
- for (msg = trpc_mq_pop(trpc);
- msg != NULL;
- msg = trpc_mq_pop(trpc)) {
- n_popped++;
+ /* Wait up to 10 minutes for a message to be queued to send to the peer.
+ * Log a warning if we go longer than that, but don't give up. */
+ if (tr_mq_pop_timeout(10 * 60, &wait_until) != 0) {
+ tr_err("tr_trpc_thread: unable to set abort timeout");
+ break; /* immediately exit the loop, don't go through cleanup */
+ }
+
+ /* Pop a message from the queue. */
+ msg = trpc_mq_pop(trpc, &wait_until);
+ if (msg) {
msg_type = tr_mq_msg_get_message(msg);
if (0 == strcmp(msg_type, TR_MQMSG_ABORT)) {
+ tr_debug("tr_trpc_thread: received abort message from main thread.");
exit_loop = 1;
- break;
} else if (0 == strcmp(msg_type, TR_MQMSG_TRPC_SEND)) {
encoded_msg = tr_mq_msg_get_payload(msg);
if (encoded_msg == NULL)
else {
rc = trpc_send_msg(trpc, encoded_msg);
if (rc == TRP_SUCCESS) {
- n_sent++;
+ tr_debug("tr_trpc_thread: sent message.");
} else {
tr_notice("tr_trpc_thread: trpc_send_msg failed.");
/* Assume this means we lost the connection. */
exit_loop = 1;
- break;
}
}
} else
tr_notice("tr_trpc_thread: unknown message '%s' received.", msg_type);
tr_mq_msg_free(msg);
+ } else {
+ tr_warning("tr_trpc_thread: no outgoing messages to %.*s for 10 minutes",
+ peer_gssname->len, peer_gssname->buf);
}
-
- /* if n_popped == 0, then n_sent must be zero (it's only set after at
- * least one msg is popped) */
- if (n_popped==0)
- tr_err("tr_trpc_thread: notified of message, but queue empty");
- else
- tr_debug("tr_trpc_thread: sent %d messages.", n_sent);
}
}
- tr_debug("tr_trpc_thread: Disconnected. Waiting to terminate thread.");
- trpc->shutting_down = 1;
-
/* Send a DISCONNECTED message to the main thread */
+ tr_debug("tr_trpc_thread: notifying main thread of disconnection.");
msg=tr_mq_msg_new(tmp_ctx, TR_MQMSG_TRPC_DISCONNECTED, TR_MQ_PRIO_NORMAL);
tr_mq_msg_set_payload(msg, (void *)trpc, NULL); /* do not pass a free routine */
if (msg==NULL) {
- /* can't notify main thread of exit - just do it and hope for the best */
+ /* can't notify main thread */
tr_err("tr_trpc_thread: error allocating TR_MQ_MSG");
} else {
trps_mq_add(trps, msg);
-
- /* DISCONNECTED sent, now wait for an acknowledgement before exiting */
- exit_loop = 0;
- while (!exit_loop) {
- trpc_thread_wait_for_message(&cb_data);
-
- while (NULL != (msg = trpc_mq_pop(trpc))) {
- msg_type = tr_mq_msg_get_message(msg);
-
- /* ignore anything except an EXIT_OK */
- if (0 == strcmp(msg_type, TR_MQMSG_TRPC_EXIT_OK)) {
- exit_loop = 1;
- break; /* skip any further messages */
- }
- }
- }
}
- tr_debug("tr_trpc_thread: thread terminating.");
talloc_free(tmp_ctx);
+ tr_debug("tr_trpc_thread: thread terminating.");
return NULL;
}
projects / trust_router.git / commitdiff