/*-------------------------------------------------------------------------*/
static void
pro_clear_instance_info(p_inst_info * ii) {
ii->iid = 0;
ii->status = empty;
ii->my_ballot = 0;
ii->p1_value_ballot = 0;
ii->promises_bitvector = 0;
ii->promises_count = 0;
if(ii->p1_value != NULL) {
PAX_FREE(ii->p1_value);
}
ii->p1_value = NULL;
if(ii->p2_value != NULL) {
PAX_FREE(ii->p2_value);
}
ii->p2_value = NULL;
}
static void
pro_save_prepare_ack(p_inst_info * ii, prepare_ack * pa, short int acceptor_id) {
//Ack from already received!
if(ii->promises_bitvector & (1<acceptor_id)) {
LOG(DBG, ("Dropping duplicate promise from:%d, iid:%ld, \n", acceptor_id, ii->iid));
return;
}
// promise is new
ii->promises_bitvector &= (1<acceptor_id);
ii->promises_count++;
LOG(DBG, ("Received valid promise from:%d, iid:%ld, \n", acceptor_id, ii->iid));
//Promise contains no value
if(pa->value_size == 0) {
LOG(DBG, (" No value in promise\n"));
return;
}
//Promise contains a value
//Our value has same or greater ballot
if(ii->p1_value_ballot >= pa->value_ballot) {
//Keep the current value
LOG(DBG, (" Included value is ignored (cause:value_ballot)\n"));
return;
}
//Ballot is greater but the value is actually the same
if ((ii->p1_value != NULL) &&
(ii->p1_value->value_size == pa->value_size) &&
(memcmp(ii->p1_value->value, pa->value, pa->value_size) == 0)) {
//Just update the value ballot
LOG(DBG, (" Included value is the same with higher value_ballot\n"));
ii->p1_value_ballot = pa->value_ballot;
return;
}
//Value should replace the one we have (if any)
//Free the old one
if (ii->p1_value != NULL) {
PAX_FREE(ii->p1_value);
}
//Save the received value
ii->p1_value = vh_wrap_value(pa->value, pa->value_size);
ii->p1_value_ballot = pa->value_ballot;
LOG(DBG, (" Value in promise saved\n"));
}
static void
leader_check_p1_pending() {
iid_t iid_iterator;
p_inst_info * ii;
//Create an empty prepare batch in send buffer
sendbuf_clear(to_acceptors, prepare_reqs, this_proposer_id);
LOG(DBG, ("Checking pending phase 1 from %lu to %lu\n",
current_iid, p1_info.highest_open));
//Get current time for checking expired
struct timeval time_now;
gettimeofday(&time_now, NULL);
for(iid_iterator = current_iid;
iid_iterator <= p1_info.highest_open; iid_iterator++) {
//Get instance from state array
ii = GET_PRO_INSTANCE(iid_iterator);
assert(ii->iid == iid_iterator);
//Still pending -> it's expired
if(ii->status == p1_pending && leader_is_expired(&ii->timeout, &time_now)) {
LOG(DBG, ("Phase 1 of instance %ld expired!\n", ii->iid));
//Reset fields used for previous phase 1
ii->promises_bitvector = 0;
ii->promises_count = 0;
ii->p1_value_ballot = 0;
if(ii->p1_value != NULL) {
PAX_FREE(ii->p1_value);
}
ii->p1_value = NULL;
//Ballot is incremented
ii->my_ballot = NEXT_BALLOT(ii->my_ballot);
//Send prepare to acceptors
sendbuf_add_prepare_req(to_acceptors, ii->iid, ii->my_ballot);
leader_set_expiration(ii, P1_TIMEOUT_INTERVAL);
COUNT_EVENT(p1_timeout);
}
}
//Send if something is still there
sendbuf_flush(to_acceptors);
}
void
vh_shutdown() {
//Delete event
event_del(&leader_msg_event);
//Close socket and free receiver
udp_receiver_destroy(for_leader);
//All values in pending could not be delivered yet.
// Notify the respective clients
vh_value_wrapper * vw;
while ((vw = vh_get_next_pending()) != NULL) {
vh_notify_client(-1, vw);
PAX_FREE(vw);
}
}
static void
leader_execute_p2(p_inst_info * ii) {
if(ii->p1_value == NULL && ii->p2_value == NULL) {
//Happens when p1 completes without value
//Assign a p2_value and execute
ii->p2_value = vh_get_next_pending();
assert(ii->p2_value != NULL);
} else if (ii->p1_value != NULL) {
//Only p1 value is present, MUST execute p2 with it
//Save it as p2 value and execute
ii->p2_value = ii->p1_value;
ii->p1_value = NULL;
ii->p1_value_ballot = 0;
} else if (ii->p2_value != NULL) {
// Only p2 valye is present
//Do phase 2 with it
} else {
// There are both p1 and p2 value
//Compare them
if(vh_value_compare(ii->p1_value, ii->p2_value) == 0) {
// Same value, just delete p1_value
PAX_FREE(ii->p1_value);
ii->p1_value = NULL;
ii->p1_value_ballot = 0;
} else {
// Different values
// p2_value is pushed back to pending list
vh_push_back_value(ii->p2_value);
// Must execute p2 with p1 value
ii->p2_value = ii->p1_value;
ii->p1_value = NULL;
ii->p1_value_ballot = 0;
}
}
//Change instance status
ii->status = p2_pending;
//Send the accept request
sendbuf_add_accept_req(to_acceptors, ii->iid, ii->my_ballot, ii->p2_value->value, ii->p2_value->value_size);
//Set the deadline for this instance
leader_set_expiration(ii, P2_TIMEOUT_INTERVAL);
}