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	diff --git a/src/raft.c b/src/raft.c
	index ab10a2a..107f0eb 100644
	--- a/src/raft.c
	+++ b/src/raft.c
	@@ -1,927 +1,929 @@
	/*
	* Copyright (C) 2014 Philipp Marek <philipp.marek@linbit.com>
	*
	* This program is free software; you can redistribute it and/or
	* modify it under the terms of the GNU General Public
	* License as published by the Free Software Foundation; either
	* version 2.1 of the License, or (at your option) any later version.
	*
	* This software is distributed in the hope that it will be useful,
	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	* General Public License for more details.
	*
	* You should have received a copy of the GNU General Public
	* License along with this library; if not, write to the Free Software
	* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
	*/

	#include <stdlib.h>
	#include <inttypes.h>
	#include <string.h>
	#include <errno.h>
	#include <arpa/inet.h>
	#include "booth.h"
	#include "transport.h"
	#include "inline-fn.h"
	#include "config.h"
	#include "raft.h"
	#include "ticket.h"
	#include "log.h"



	inline static void clear_election(struct ticket_config *tk)
	{
	int i;
	struct booth_site *site;

	tk_log_debug("clear election");
	tk->votes_received = 0;
	foreach_node(i, site)
	tk->votes_for[site->index] = NULL;
	}


	inline static void record_vote(struct ticket_config *tk,
	struct booth_site *who,
	struct booth_site *vote)
	{
	tk_log_debug("site %s votes for %s",
	site_string(who),
	site_string(vote));

	if (!tk->votes_for[who->index]) {
	tk->votes_for[who->index] = vote;
	tk->votes_received \|= who->bitmask;
	} else {
	if (tk->votes_for[who->index] != vote)
	tk_log_warn("%s voted previously "
	"for %s and now wants to vote for %s (ignored)",
	site_string(who),
	site_string(tk->votes_for[who->index]),
	site_string(vote));
	}
	}


	static int cmp_msg_ticket(struct ticket_config *tk,
	struct booth_site *sender,
	struct booth_site *leader,
	struct boothc_ticket_msg *msg)
	{
	if (my_last_term(tk) != ntohl(msg->ticket.term)) {
	return my_last_term(tk) - ntohl(msg->ticket.term);
	}
	return 0;
	}

	static void update_term_from_msg(struct ticket_config *tk,
	struct boothc_ticket_msg *msg)
	{
	uint32_t i;


	i = ntohl(msg->ticket.term);
	/* if we failed to start the election, then accept the term
	* from the leader
	* */
	if (tk->state == ST_CANDIDATE) {
	tk->current_term = i;
	} else {
	tk->current_term = max(i, tk->current_term);
	}
	}


	static void update_ticket_from_msg(struct ticket_config *tk,
	struct booth_site *sender,
	struct boothc_ticket_msg *msg)
	{
	int duration;

	tk_log_debug("updating from %s (%d/%d)",
	site_string(sender),
	ntohl(msg->ticket.term), ntohl(msg->ticket.term_valid_for));
	duration = min(tk->term_duration, ntohl(msg->ticket.term_valid_for));
	tk->term_expires = time(NULL) + duration;
	update_term_from_msg(tk, msg);
	}


	static void copy_ticket_from_msg(struct ticket_config *tk,
	struct boothc_ticket_msg *msg)
	{
	tk->term_expires = time(NULL) + ntohl(msg->ticket.term_valid_for);
	tk->current_term = ntohl(msg->ticket.term);
	}

	static void become_follower(struct ticket_config *tk,
	struct boothc_ticket_msg *msg)
	{
	copy_ticket_from_msg(tk, msg);
	tk->state = ST_FOLLOWER;
	tk->delay_commit = 0;
	/* if we're following and the ticket was granted here
	* then commit to CIB right away (we're probably restarting)
	*/
	if (tk->is_granted) {
	disown_ticket(tk);
	ticket_write(tk);
	}
	}


	static void won_elections(struct ticket_config *tk)
	{
	tk->leader = local;
	tk->state = ST_LEADER;

	tk->term_expires = time(NULL) + tk->term_duration;
	tk->election_end = 0;
	tk->voted_for = NULL;

	ticket_broadcast(tk, OP_HEARTBEAT, OP_ACK, RLT_SUCCESS, 0);
	ticket_activate_timeout(tk);
	}


	static int is_tie(struct ticket_config *tk)
	{
	int i;
	struct booth_site *v;
	int count[MAX_NODES] = { 0, };
	int max_votes = 0, max_cnt = 0;

	for(i=0; i<booth_conf->site_count; i++) {
	v = tk->votes_for[i];
	if (!v)
	continue;
	count[v->index]++;
	max_votes = max(max_votes, count[v->index]);
	}

	for(i=0; i<booth_conf->site_count; i++) {
	if (count[i] == max_votes)
	max_cnt++;
	}

	return max_cnt > 1;
	}

	static struct booth_site majority_votes(struct ticket_config tk)
	{
	int i, n;
	struct booth_site *v;
	int count[MAX_NODES] = { 0, };


	for(i=0; i<booth_conf->site_count; i++) {
	v = tk->votes_for[i];
	if (!v)
	continue;

	n = v->index;
	count[n]++;
	tk_log_debug("Majority: %d %s wants %d %s => %d",
	i, site_string(&booth_conf->site[i]),
	n, site_string(v),
	count[n]);

	if (count[n]*2 <= booth_conf->site_count)
	continue;


	tk_log_debug("Majority reached: %d of %d for %s",
	count[n], booth_conf->site_count,
	site_string(v));
	return v;
	}

	return NULL;
	}


	void elections_end(struct ticket_config *tk)
	{
	time_t now;
	struct booth_site *new_leader;

	now = time(NULL);
	if (now > tk->election_end) {
	/* This is previous election timed out */
	tk_log_info("election timed out");
	}

	+ tk->in_election = 0;
	new_leader = majority_votes(tk);
	if (new_leader == local) {
	tk_log_info("granted successfully here");
	won_elections(tk);
	} else if (new_leader) {
	tk_log_info("ticket granted at %s",
	site_string(new_leader));
	} else {
	tk_log_info("nobody won elections, new elections");
	new_election(tk, NULL, is_tie(tk), OR_AGAIN);
	}
	}


	static int newer_term(struct ticket_config *tk,
	struct booth_site *sender,
	struct booth_site *leader,
	struct boothc_ticket_msg *msg,
	int in_election)
	{
	uint32_t term;

	/* it may happen that we hear about our newer term */
	if (leader == local)
	return 0;

	term = ntohl(msg->ticket.term);
	/* §5.1 */
	if (term > tk->current_term) {
	tk->state = ST_FOLLOWER;
	if (!in_election) {
	tk->leader = leader;
	tk_log_info("from %s: higher term %d vs. %d, following %s",
	site_string(sender),
	term, tk->current_term,
	ticket_leader_string(tk));
	} else {
	tk_log_debug("from %s: higher term %d vs. %d (election)",
	site_string(sender),
	term, tk->current_term);
	}

	tk->current_term = term;
	return 1;
	}

	return 0;
	}

	static int term_too_low(struct ticket_config *tk,
	struct booth_site *sender,
	struct booth_site *leader,
	struct boothc_ticket_msg *msg)
	{
	uint32_t term;

	term = ntohl(msg->ticket.term);
	/* §5.1 */
	if (term < tk->current_term) {
	tk_log_info("sending reject to %s, its term too low "
	"(%d vs. %d)", site_string(sender),
	term, tk->current_term
	);
	send_reject(sender, tk, RLT_TERM_OUTDATED, msg);
	return 1;
	}

	return 0;
	}




	/* For follower. */
	static int answer_HEARTBEAT (
	struct ticket_config *tk,
	struct booth_site *sender,
	struct booth_site *leader,
	struct boothc_ticket_msg *msg
	)
	{
	uint32_t term;

	term = ntohl(msg->ticket.term);
	tk_log_debug("heartbeat from leader: %s, have %s; term %d vs %d",
	site_string(leader), ticket_leader_string(tk),
	term, tk->current_term);

	if (term < tk->current_term) {
	if (sender == tk->leader) {
	tk_log_info("trusting leader %s with a lower term (%d vs %d)",
	site_string(leader), term, tk->current_term);
	} else if (is_owned(tk)) {
	tk_log_warn("different leader %s with a lower term "
	"(%d vs %d), sending reject",
	site_string(leader), term, tk->current_term);
	return send_reject(sender, tk, RLT_TERM_OUTDATED, msg);
	}
	}

	/* got heartbeat, no rejects expected anymore */
	tk->expect_more_rejects = 0;

	/* and certainly not in election */
	tk->in_election = 0;

	/* Needed? */
	newer_term(tk, sender, leader, msg, 0);

	become_follower(tk, msg);
	/* Racy??? */
	assert(sender == leader \|\| !leader);

	tk->leader = leader;

	/* Ack the heartbeat (we comply). */
	return send_msg(OP_ACK, tk, sender, msg);
	}


	static int process_UPDATE (
	struct ticket_config *tk,
	struct booth_site *sender,
	struct booth_site *leader,
	struct boothc_ticket_msg *msg
	)
	{
	if (is_owned(tk) && sender != tk->leader) {
	tk_log_warn("different leader %s wants to update "
	"our ticket, sending reject",
	site_string(leader));
	return send_reject(sender, tk, RLT_TERM_OUTDATED, msg);
	}

	tk_log_debug("leader %s wants to update our ticket",
	site_string(leader));

	tk->leader = leader;
	copy_ticket_from_msg(tk, msg);
	ticket_write(tk);

	/* run ticket_cron if the ticket expires */
	set_ticket_wakeup(tk);

	return send_msg(OP_ACK, tk, sender, msg);
	}

	static int process_REVOKE (
	struct ticket_config *tk,
	struct booth_site *sender,
	struct booth_site *leader,
	struct boothc_ticket_msg *msg
	)
	{
	int rv;

	if (tk->state == ST_INIT && tk->leader == no_leader) {
	/* assume that our ack got lost */
	rv = send_msg(OP_ACK, tk, sender, msg);
	} else if (tk->leader != sender) {
	tk_log_error("%s wants to revoke ticket, "
	"but it is not granted there (ignoring)",
	site_string(sender));
	return 1;
	} else if (tk->state != ST_FOLLOWER) {
	tk_log_error("unexpected ticket revoke from %s "
	"(in state %s) (ignoring)",
	site_string(sender),
	state_to_string(tk->state));
	return 1;
	} else {
	tk_log_info("%s revokes ticket",
	site_string(tk->leader));
	reset_ticket(tk);
	tk->leader = no_leader;
	ticket_write(tk);
	rv = send_msg(OP_ACK, tk, sender, msg);
	}

	return rv;
	}


	/* For leader. */
	static int process_ACK(
	struct ticket_config *tk,
	struct booth_site *sender,
	struct booth_site *leader,
	struct boothc_ticket_msg *msg
	)
	{
	uint32_t term;

	term = ntohl(msg->ticket.term);

	if (newer_term(tk, sender, leader, msg, 0)) {
	/* unexpected higher term */
	tk_log_warn("got higher term from %s (%d vs. %d)",
	site_string(sender),
	term, tk->current_term);
	return 0;
	}

	/* Don't send a reject. */
	if (term < tk->current_term) {
	/* Doesn't know what he's talking about - perhaps
	* doesn't receive our packets? */
	tk_log_warn("unexpected term "
	"from %s (%d vs. %d) (ignoring)",
	site_string(sender),
	term, tk->current_term);
	return 0;
	}

	/* if the ticket is to be revoked, further processing is not
	* interesting (and dangerous) */
	if (tk->next_state == ST_INIT \|\| tk->state == ST_INIT)
	return 0;

	/* for heartbeats we make do with the majority */
	if (tk->last_request == OP_HEARTBEAT &&
	term == tk->current_term &&
	leader == tk->leader) {

	if (majority_of_bits(tk, tk->acks_received)) {
	/* OK, at least half of the nodes are reachable;
	* Update the ticket and send update messages out
	*/
	return leader_update_ticket(tk);
	}
	}

	return 0;
	}


	static int process_VOTE_FOR(
	struct ticket_config *tk,
	struct booth_site *sender,
	struct booth_site *leader,
	struct boothc_ticket_msg *msg
	)
	{
	/* leader wants to step down? */
	if (leader == no_leader && sender == tk->leader &&
	(tk->state == ST_FOLLOWER \|\| tk->state == ST_CANDIDATE)) {
	tk_log_info("%s wants to give the ticket away",
	site_string(tk->leader));
	reset_ticket(tk);
	tk->state = ST_FOLLOWER;
	if (local->type == SITE) {
	ticket_write(tk);
	schedule_election(tk, OR_STEPDOWN);
	}
	return 0;
	}

	if (tk->state != ST_CANDIDATE) {
	/* lost candidate status, somebody rejected our proposal */
	tk_log_debug("candidate status lost, ignoring vote_for from %s",
	site_string(sender));
	return 0;
	}

	if (term_too_low(tk, sender, leader, msg))
	return 0;

	if (newer_term(tk, sender, leader, msg, 0)) {
	clear_election(tk);
	}

	record_vote(tk, sender, leader);

	/* only if all voted can we take the ticket now, otherwise
	* wait for timeout in ticket_cron */
	if (!tk->acks_expected) {
	/* §5.2 */
	elections_end(tk);
	}

	return 0;
	}


	static int process_REJECTED(
	struct ticket_config *tk,
	struct booth_site *sender,
	struct booth_site *leader,
	struct boothc_ticket_msg *msg
	)
	{
	uint32_t rv;

	rv = ntohl(msg->header.result);

	if (tk->state == ST_CANDIDATE &&
	leader == local) {
	/* the sender has us as the leader (!)
	* the elections will time out, then we can try again
	*/
	tk_log_warn("ticket was granted to us "
	"(and we didn't know)");
	tk->expect_more_rejects = 1;
	return 0;
	}

	if (tk->state == ST_CANDIDATE &&
	rv == RLT_TERM_OUTDATED) {
	tk_log_warn("ticket outdated (term %d), granted to %s",
	ntohl(msg->ticket.term),
	site_string(leader)
	);
	tk->leader = leader;
	tk->expect_more_rejects = 1;
	become_follower(tk, msg);
	return 0;
	}

	if (tk->state == ST_CANDIDATE &&
	rv == RLT_TERM_STILL_VALID) {
	if (tk->lost_leader == leader) {
	if (tk->election_reason == OR_TKT_LOST) {
	tk_log_warn("%s still has the ticket valid, "
	"we'll backup a bit",
	site_string(sender));
	} else {
	tk_log_warn("%s unexpecetedly rejects elections",
	site_string(sender));
	}
	} else {
	tk_log_warn("ticket was granted to %s "
	"(and we didn't know)",
	site_string(leader));
	}
	tk->leader = leader;
	become_follower(tk, msg);
	tk->expect_more_rejects = 1;
	return 0;
	}

	if (tk->state == ST_CANDIDATE &&
	rv == RLT_YOU_OUTDATED) {
	tk->leader = leader;
	tk->expect_more_rejects = 1;
	if (leader && leader != no_leader) {
	tk_log_warn("our ticket is outdated, granted to %s",
	site_string(leader));
	become_follower(tk, msg);
	} else {
	tk_log_warn("our ticket is outdated and revoked");
	update_ticket_from_msg(tk, sender, msg);
	tk->state = ST_INIT;
	}
	return 0;
	}

	if (!tk->expect_more_rejects) {
	tk_log_warn("from %s: in state %s, got %s (unexpected reject)",
	site_string(sender),
	state_to_string(tk->state),
	state_to_string(rv));
	}

	return 0;
	}


	static int ticket_seems_ok(struct ticket_config *tk)
	{
	int time_left;

	time_left = term_time_left(tk);
	if (!time_left)
	return 0; /* quite sure */
	if (tk->state == ST_CANDIDATE)
	return 0; /* in state of flux */
	if (tk->state == ST_LEADER)
	return 1; /* quite sure */
	if (tk->state == ST_FOLLOWER &&
	time_left >= tk->term_duration/3)
	return 1; /* almost quite sure */
	return 0;
	}


	static int test_reason(
	struct ticket_config *tk,
	struct booth_site *sender,
	struct booth_site *leader,
	struct boothc_ticket_msg *msg
	)
	{
	int reason;

	reason = ntohl(msg->header.reason);
	if (reason == OR_TKT_LOST) {
	if (tk->state == ST_INIT &&
	tk->leader == no_leader) {
	tk_log_warn("%s claims that the ticket is lost, "
	"but it's in %s state (reject sent)",
	site_string(sender),
	state_to_string(tk->state)
	);
	return RLT_YOU_OUTDATED;
	}
	if (ticket_seems_ok(tk)) {
	tk_log_warn("%s claims that the ticket is lost, "
	"but it is ok here (reject sent)",
	site_string(sender));
	return RLT_TERM_STILL_VALID;
	}
	}
	return 0;
	}


	/* §5.2 */
	static int answer_REQ_VOTE(
	struct ticket_config *tk,
	struct booth_site *sender,
	struct booth_site *leader,
	struct boothc_ticket_msg *msg
	)
	{
	int valid;
	struct boothc_ticket_msg omsg;
	cmd_result_t inappr_reason;

	inappr_reason = test_reason(tk, sender, leader, msg);
	if (inappr_reason)
	return send_reject(sender, tk, inappr_reason, msg);

	valid = term_time_left(tk);

	/* allow the leader to start new elections on valid tickets */
	if (sender != tk->leader && valid) {
	tk_log_warn("election from %s rejected "
	"(we have %s as ticket owner), ticket still valid for %ds",
	site_string(sender), site_string(tk->leader), valid);
	return send_reject(sender, tk, RLT_TERM_STILL_VALID, msg);
	}

	if (term_too_low(tk, sender, leader, msg))
	return 0;

	/* set this, so that we know not to send status for the
	* ticket */
	tk->in_election = 1;

	/* if it's a newer term or ... */
	if (newer_term(tk, sender, leader, msg, 1)) {
	clear_election(tk);
	goto vote_for_sender;
	}


	/* ... we didn't vote yet, then vote for the sender */
	/* §5.2, §5.4 */
	if (!tk->voted_for) {
	vote_for_sender:
	tk->voted_for = sender;
	record_vote(tk, sender, leader);
	}


	init_ticket_msg(&omsg, OP_VOTE_FOR, OP_REQ_VOTE, RLT_SUCCESS, 0, tk);
	omsg.ticket.leader = htonl(get_node_id(tk->voted_for));
	return booth_udp_send(sender, &omsg, sizeof(omsg));
	}


	int new_election(struct ticket_config *tk,
	struct booth_site *preference, int update_term, cmd_reason_t reason)
	{
	struct booth_site *new_leader;
	time_t now;

	if (local->type != SITE)
	return 0;

	time(&now);
	tk_log_debug("start new election?, now=%" PRIi64 ", end %" PRIi64,
	(int64_t)now, (int64_t)(tk->election_end));
	if (now < tk->election_end)
	return 0;

	/* §5.2 */
	/* If there was _no_ answer, don't keep incrementing the term number
	* indefinitely. If there was no peer, there'll probably be no one
	* listening now either. However, we don't know if we were
	* invoked due to a timeout (caller does).
	*/
	if (update_term) {
	/* save the previous term, we may need to send out the
	* MY_INDEX message */
	if (tk->state != ST_CANDIDATE) {
	memcpy(tk->last_valid_tk, tk, sizeof(struct ticket_config));
	}
	tk->current_term++;
	}

	tk->term_expires = 0;
	tk->election_end = now + tk->timeout;
	+ tk->in_election = 1;

	tk_log_info("starting new election (term=%d)",
	tk->current_term);
	clear_election(tk);

	if(preference)
	new_leader = preference;
	else
	new_leader = (local->type == SITE) ? local : NULL;
	record_vote(tk, local, new_leader);
	tk->voted_for = new_leader;

	tk->leader = no_leader;
	tk->state = ST_CANDIDATE;

	/* some callers may want just to repeat on timeout */
	if (reason == OR_AGAIN) {
	reason = tk->election_reason;
	} else {
	tk->election_reason = reason;
	}

	ticket_broadcast(tk, OP_REQ_VOTE, OP_VOTE_FOR, RLT_SUCCESS, reason);
	ticket_activate_timeout(tk);
	add_random_delay(tk);
	return 0;
	}


	/* we were a leader and somebody says that they have a more up
	* to date ticket
	* there was probably connectivity loss
	* tricky
	*/
	static int leader_handle_newer_ticket(
	struct ticket_config *tk,
	struct booth_site *sender,
	struct booth_site *leader,
	struct boothc_ticket_msg *msg
	)
	{
	update_term_from_msg(tk, msg);
	if (leader != no_leader && leader && leader != local) {
	/* eek, two leaders, split brain */
	/* normally shouldn't happen; run election */
	tk_log_error("from %s: ticket granted to %s! (revoking locally)",
	site_string(sender),
	site_string(leader)
	);
	} else if (term_time_left(tk)) {
	/* eek, two leaders, split brain */
	/* normally shouldn't happen; run election */
	tk_log_error("from %s: ticket granted to %s! (revoking locally)",
	site_string(sender),
	site_string(leader)
	);
	}
	tk->next_state = ST_LEADER;
	return 0;
	}

	/* reply to STATUS */
	static int process_MY_INDEX (
	struct ticket_config *tk,
	struct booth_site *sender,
	struct booth_site *leader,
	struct boothc_ticket_msg *msg
	)
	{
	int i;
	int expired;

	expired = !msg->ticket.term_valid_for;
	i = cmp_msg_ticket(tk, sender, leader, msg);

	if (i > 0) {
	/* let them know about our newer ticket */
	/* but if we're voting in elections, our ticket is not
	* valid yet, don't send it */
	if (!tk->in_election)
	send_msg(OP_MY_INDEX, tk, sender, msg);
	if (tk->state == ST_LEADER) {
	tk_log_info("sending ticket update to %s",
	site_string(sender));
	return send_msg(OP_UPDATE, tk, sender, msg);
	}
	}

	/* we have a newer or equal ticket and theirs is expired,
	* nothing more to do here */
	if (i >= 0 && expired) {
	return 0;
	}

	if (tk->state == ST_LEADER) {
	/* we're the leader, thread carefully */
	if (expired) {
	/* if their ticket is expired,
	* nothing more to do */
	return 0;
	}
	if (i < 0) {
	/* they have a newer ticket, trouble if we're already leader
	* for it */
	tk_log_warn("from %s: more up to date ticket at %s",
	site_string(sender),
	site_string(leader)
	);
	return leader_handle_newer_ticket(tk, sender, leader, msg);
	} else {
	/* we have the ticket and we don't care */
	return 0;
	}
	}

	/* their ticket is either newer or not expired, don't
	* ignore it */
	update_ticket_from_msg(tk, sender, msg);
	tk->leader = leader;
	update_ticket_state(tk, sender);
	set_ticket_wakeup(tk);
	return 0;
	}


	int raft_answer(
	struct ticket_config *tk,
	struct booth_site *sender,
	struct booth_site *leader,
	struct boothc_ticket_msg *msg
	)
	{
	int cmd, req;
	int rv;

	rv = 0;
	cmd = ntohl(msg->header.cmd);
	req = ntohl(msg->header.request);

	if (req)
	tk_log_debug("got %s (req %s) from %s",
	state_to_string(cmd),
	state_to_string(req),
	site_string(sender));
	else
	tk_log_debug("got %s from %s",
	state_to_string(cmd),
	site_string(sender));


	switch (cmd) {
	case OP_REQ_VOTE:
	rv = answer_REQ_VOTE(tk, sender, leader, msg);
	break;
	case OP_VOTE_FOR:
	rv = process_VOTE_FOR(tk, sender, leader, msg);
	break;
	case OP_ACK:
	if (tk->leader == local &&
	tk->state == ST_LEADER)
	rv = process_ACK(tk, sender, leader, msg);
	break;
	case OP_HEARTBEAT:
	if ((tk->leader != local \|\| !term_time_left(tk)) &&
	(tk->state == ST_INIT \|\| tk->state == ST_FOLLOWER \|\|
	tk->state == ST_CANDIDATE))
	rv = answer_HEARTBEAT(tk, sender, leader, msg);
	else {
	tk_log_warn("unexpected message %s, from %s",
	state_to_string(cmd),
	site_string(sender));
	if (ticket_seems_ok(tk))
	send_reject(sender, tk, RLT_TERM_STILL_VALID, msg);
	rv = -EINVAL;
	}
	break;
	case OP_UPDATE:
	if (((tk->leader != local && tk->leader == leader) \|\| !is_owned(tk)) &&
	tk->state == ST_FOLLOWER) {
	rv = process_UPDATE(tk, sender, leader, msg);
	} else {
	tk_log_warn("unexpected message %s, from %s",
	state_to_string(cmd),
	site_string(sender));
	if (ticket_seems_ok(tk))
	send_reject(sender, tk, RLT_TERM_STILL_VALID, msg);
	rv = -EINVAL;
	}
	break;
	case OP_REJECTED:
	rv = process_REJECTED(tk, sender, leader, msg);
	break;
	case OP_REVOKE:
	rv = process_REVOKE(tk, sender, leader, msg);
	break;
	case OP_MY_INDEX:
	rv = process_MY_INDEX(tk, sender, leader, msg);
	break;
	case OP_STATUS:
	if (!tk->in_election)
	rv = send_msg(OP_MY_INDEX, tk, sender, msg);
	break;
	default:
	tk_log_error("unknown message %s, from %s",
	state_to_string(cmd), site_string(sender));
	rv = -EINVAL;
	}
	return rv;
	}
	diff --git a/src/ticket.c b/src/ticket.c
	index 26deda9..836811d 100644
	--- a/src/ticket.c
	+++ b/src/ticket.c
	@@ -1,1077 +1,1077 @@
	/*
	* Copyright (C) 2011 Jiaju Zhang <jjzhang@suse.de>
	* Copyright (C) 2013-2014 Philipp Marek <philipp.marek@linbit.com>
	*
	* This program is free software; you can redistribute it and/or
	* modify it under the terms of the GNU General Public
	* License as published by the Free Software Foundation; either
	* version 2.1 of the License, or (at your option) any later version.
	*
	* This software is distributed in the hope that it will be useful,
	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	* General Public License for more details.
	*
	* You should have received a copy of the GNU General Public
	* License along with this library; if not, write to the Free Software
	* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
	*/

	#include <stdlib.h>
	#include <string.h>
	#include <errno.h>
	#include <arpa/inet.h>
	#include <inttypes.h>
	#include <stdio.h>
	#include <assert.h>
	#include <time.h>
	#include <clplumbing/cl_random.h>
	#include "ticket.h"
	#include "config.h"
	#include "pacemaker.h"
	#include "inline-fn.h"
	#include "log.h"
	#include "booth.h"
	#include "raft.h"
	#include "handler.h"

	#define TK_LINE 256


	/* Untrusted input, must fit (incl. \0) in a buffer of max chars. */
	int check_max_len_valid(const char *s, int max)
	{
	int i;
	for(i=0; i<max; i++)
	if (s[i] == 0)
	return 1;
	return 0;
	}

	int find_ticket_by_name(const char ticket, struct ticket_config *found)
	{
	int i;

	if (found)
	*found = NULL;

	for (i = 0; i < booth_conf->ticket_count; i++) {
	if (!strcmp(booth_conf->ticket[i].name, ticket)) {
	if (found)
	*found = booth_conf->ticket + i;
	return 1;
	}
	}

	return 0;
	}


	int check_ticket(char ticket, struct ticket_config *found)
	{
	if (found)
	*found = NULL;
	if (!booth_conf)
	return 0;

	if (!check_max_len_valid(ticket, sizeof(booth_conf->ticket[0].name)))
	return 0;
	return find_ticket_by_name(ticket, found);
	}

	int check_site(char site, int is_local)
	{
	struct booth_site *node;

	if (!check_max_len_valid(site, sizeof(node->addr_string)))
	return 0;

	if (find_site_by_name(site, &node, 0)) {
	*is_local = node->local;
	return 1;
	}

	return 0;
	}


	int ticket_write(struct ticket_config *tk)
	{
	if (local->type != SITE)
	return -EINVAL;

	if (tk->leader == local) {
	pcmk_handler.grant_ticket(tk);
	} else {
	pcmk_handler.revoke_ticket(tk);
	}
	tk->update_cib = 0;

	return 0;
	}


	/* Ask an external program whether getting the ticket
	* makes sense.
	* Eg. if the services have a failcount of INFINITY,
	* we can't serve here anyway. */
	int test_external_prog(struct ticket_config *tk,
	int start_election)
	{
	int rv;

	rv = run_handler(tk, tk->ext_verifier, 1);
	if (rv) {
	tk_log_warn("we are not allowed to acquire ticket");

	/* Give it to somebody else.
	* Just send a VOTE_FOR message, so the
	* others can start elections. */
	if (leader_and_valid(tk)) {
	reset_ticket(tk);
	ticket_write(tk);
	if (start_election) {
	ticket_broadcast(tk, OP_VOTE_FOR, OP_REQ_VOTE, RLT_SUCCESS, OR_LOCAL_FAIL);
	}
	}
	}

	return rv;
	}


	/* Try to acquire a ticket
	* Could be manual grant or after ticket loss
	*/
	int acquire_ticket(struct ticket_config *tk, cmd_reason_t reason)
	{
	if (test_external_prog(tk, 0))
	return RLT_EXT_FAILED;

	return new_election(tk, local, 1, reason);
	}


	/** Try to get the ticket for the local site.
	* */
	int do_grant_ticket(struct ticket_config *tk, int options)
	{
	int rv;

	tk_log_info("granting ticket");

	if (tk->leader == local)
	return RLT_SUCCESS;
	if (is_owned(tk))
	return RLT_OVERGRANT;

	tk->delay_commit = time(NULL) +
	tk->term_duration + tk->acquire_after;

	if (options & OPT_IMMEDIATE) {
	tk_log_warn("granting ticket immediately! If there are "
	"unreachable sites, _hope_ you are sure that they don't "
	"have the ticket!");
	tk->delay_commit = 0;
	}

	rv = acquire_ticket(tk, OR_ADMIN);
	if (rv)
	tk->delay_commit = 0;
	return rv;
	}


	static int start_revoke_ticket(struct ticket_config *tk)
	{
	tk_log_info("revoking ticket");

	reset_ticket(tk);
	tk->leader = no_leader;
	ticket_write(tk);
	ticket_activate_timeout(tk);
	return ticket_broadcast(tk, OP_REVOKE, OP_ACK, RLT_SUCCESS, OR_ADMIN);
	}

	/** Ticket revoke.
	* Only to be started from the leader. */
	int do_revoke_ticket(struct ticket_config *tk)
	{
	if (tk->acks_expected) {
	tk_log_info("delay ticket revoke until the current operation finishes");
	tk->next_state = ST_INIT;
	return 0;
	} else {
	return start_revoke_ticket(tk);
	}
	}


	int list_ticket(char *pdata, unsigned int len)
	{
	struct ticket_config *tk;
	char timeout_str[64];
	char pending_str[64];
	char data, cp;
	int i, alloc;

	*pdata = NULL;
	*len = 0;

	alloc = 256 +
	booth_conf->ticket_count * (BOOTH_NAME_LEN * 2 + 128);
	data = malloc(alloc);
	if (!data)
	return -ENOMEM;

	cp = data;
	foreach_ticket(i, tk) {
	if (tk->term_expires != 0)
	strftime(timeout_str, sizeof(timeout_str), "%F %T",
	localtime(&tk->term_expires));
	else
	strcpy(timeout_str, "N/A");

	if (tk->leader == local && tk->delay_commit > time(NULL)) {
	strcpy(pending_str, " (commit pending until ");
	strftime(pending_str + strlen(" (commit pending until "),
	sizeof(pending_str) - strlen(" (commit pending until ") - 1,
	"%F %T", localtime(&tk->delay_commit));
	strcat(pending_str, ")");
	} else
	*pending_str = '\0';

	cp += snprintf(cp,
	alloc - (cp - data),
	"ticket: %s, leader: %s",
	tk->name,
	ticket_leader_string(tk));

	if (is_owned(tk)) {
	cp += snprintf(cp,
	alloc - (cp - data),
	", expires: %s%s\n",
	timeout_str,
	pending_str);
	} else {
	cp += snprintf(cp, alloc - (cp - data), "\n");
	}

	if (alloc - (cp - data) <= 0)
	return -ENOMEM;
	}

	*pdata = data;
	*len = cp - data;

	return 0;
	}

	void reset_ticket(struct ticket_config *tk)
	{
	disown_ticket(tk);
	tk->state = ST_INIT;
	tk->voted_for = NULL;
	}


	static void reacquire_ticket(struct ticket_config *tk)
	{
	int valid;
	const char *where_granted = "\0";
	char buff[64];

	valid = (tk->term_expires >= time(NULL));

	if (tk->leader == local) {
	where_granted = "granted here";
	} else {
	snprintf(buff, sizeof(buff), "granted to %s",
	site_string(tk->leader));
	where_granted = buff;
	}

	if (!valid) {
	tk_log_warn("%s, but not valid "
	"anymore (will try to reacquire)", where_granted);
	}
	if (tk->is_granted && tk->leader != local) {
	if (tk->leader && tk->leader != no_leader) {
	tk_log_error("granted here, but also %s, "
	"that's really too bad (will try to reacquire)",
	where_granted);
	} else {
	tk_log_warn("granted here, but we're "
	"not recorded as the grantee (will try to reacquire)");
	}
	}

	/* try to acquire the
	* ticket through new elections
	*/
	acquire_ticket(tk, OR_REACQUIRE);
	}

	void update_ticket_state(struct ticket_config tk, struct booth_site sender)
	{
	if (tk->state == ST_CANDIDATE) {
	tk_log_info("learned from %s about "
	"newer ticket, stopping elections",
	site_string(sender));
	/* there could be rejects coming from others; don't log
	* warnings unnecessarily */
	tk->expect_more_rejects = 1;
	}

	if (tk->leader == local \|\| tk->is_granted) {
	/* message from a live leader with valid ticket? */
	if (sender == tk->leader && term_time_left(tk)) {
	if (tk->is_granted) {
	tk_log_warn("ticket was granted here, "
	"but it's live at %s (revoking here)",
	site_string(sender));
	} else {
	tk_log_info("ticket live at %s",
	site_string(sender));
	}
	disown_ticket(tk);
	ticket_write(tk);
	tk->state = ST_FOLLOWER;
	tk->next_state = ST_FOLLOWER;
	} else {
	if (tk->state == ST_CANDIDATE) {
	tk->state = ST_FOLLOWER;
	}
	tk->next_state = ST_LEADER;
	}
	} else {
	if (!tk->leader \|\| tk->leader == no_leader) {
	if (sender)
	tk_log_info("ticket is not granted");
	else
	tk_log_info("ticket is not granted (from CIB)");
	tk->state = ST_INIT;
	} else {
	if (sender)
	tk_log_info("ticket granted to %s (says %s)",
	site_string(tk->leader),
	site_string(sender));
	else
	tk_log_info("ticket granted to %s (from CIB)",
	site_string(tk->leader));
	tk->state = ST_FOLLOWER;
	/* just make sure that we check the ticket soon */
	tk->next_state = ST_FOLLOWER;
	}
	}
	}

	int setup_ticket(void)
	{
	struct ticket_config *tk;
	int i;

	foreach_ticket(i, tk) {
	reset_ticket(tk);

	if (local->type == SITE) {
	if (!pcmk_handler.load_ticket(tk)) {
	update_ticket_state(tk, NULL);
	}
	tk->update_cib = 1;
	}

	tk_log_info("broadcasting state query");
	/* wait until all send their status (or the first
	* timeout) */
	tk->start_postpone = 1;
	ticket_broadcast(tk, OP_STATUS, OP_MY_INDEX, RLT_SUCCESS, 0);
	}

	return 0;
	}


	int ticket_answer_list(int fd, struct boothc_ticket_msg *msg)
	{
	char *data;
	int olen, rv;
	struct boothc_header hdr;

	rv = list_ticket(&data, &olen);
	if (rv < 0)
	return rv;

	init_header(&hdr, CMR_LIST, 0, 0, RLT_SUCCESS, 0, sizeof(hdr) + olen);

	return send_header_plus(fd, &hdr, data, olen);
	}


	int ticket_answer_grant(int fd, struct boothc_ticket_msg *msg)
	{
	int rv;
	struct ticket_config *tk;


	if (!check_ticket(msg->ticket.id, &tk)) {
	log_warn("client asked to grant unknown ticket %s",
	msg->ticket.id);
	rv = RLT_INVALID_ARG;
	goto reply;
	}

	if (is_owned(tk)) {
	log_warn("client wants to grant an (already granted!) ticket %s",
	msg->ticket.id);
	rv = RLT_OVERGRANT;
	goto reply;
	}

	rv = do_grant_ticket(tk, ntohl(msg->header.options));

	reply:
	init_header(&msg->header, CMR_GRANT, 0, 0, rv ?: RLT_ASYNC, 0, sizeof(*msg));
	return send_ticket_msg(fd, msg);
	}


	int ticket_answer_revoke(int fd, struct boothc_ticket_msg *msg)
	{
	int rv;
	struct ticket_config *tk;

	if (!check_ticket(msg->ticket.id, &tk)) {
	log_warn("client wants to revoke an unknown ticket %s",
	msg->ticket.id);
	rv = RLT_INVALID_ARG;
	goto reply;
	}

	if (!is_owned(tk)) {
	log_info("client wants to revoke a free ticket %s",
	msg->ticket.id);
	rv = RLT_TICKET_IDLE;
	goto reply;
	}

	if (tk->leader != local) {
	log_info("the ticket %s is not granted here, "
	"redirect to %s",
	msg->ticket.id, ticket_leader_string(tk));
	rv = RLT_REDIRECT;
	goto reply;
	}

	rv = do_revoke_ticket(tk);
	if (rv == 0)
	rv = RLT_ASYNC;

	reply:
	init_ticket_msg(msg, CMR_REVOKE, 0, rv, 0, tk);
	return send_ticket_msg(fd, msg);
	}


	int ticket_broadcast(struct ticket_config *tk,
	cmd_request_t cmd, cmd_request_t expected_reply,
	cmd_result_t res, cmd_reason_t reason)
	{
	struct boothc_ticket_msg msg;

	init_ticket_msg(&msg, cmd, 0, res, reason, tk);
	tk_log_debug("broadcasting '%s' (term=%d, valid=%d)",
	state_to_string(cmd),
	ntohl(msg.ticket.term),
	ntohl(msg.ticket.term_valid_for));

	tk->last_request = cmd;
	if (expected_reply) {
	expect_replies(tk, expected_reply);
	}
	return transport()->broadcast(&msg, sizeof(msg));
	}


	/* is it safe to commit the grant?
	* if we didn't hear from all sites on the initial grant, we may
	* need to delay the commit
	*
	* TODO: investigate possibility to devise from history whether a
	* missing site could be holding a ticket or not
	*/
	static int ticket_dangerous(struct ticket_config *tk)
	{
	if (!tk->delay_commit)
	return 0;

	if (tk->delay_commit <= time(NULL) \|\|
	all_sites_replied(tk)) {
	tk_log_debug("ticket delay commit expired");
	tk->delay_commit = 0;
	return 0;
	} else {
	tk_log_debug("delay ticket commit for %ds",
	(int)(tk->delay_commit - time(NULL)));
	}

	return 1;
	}


	/* update the ticket on the leader, write it to the CIB, and
	send out the update message to others with the new expiry
	time
	*/
	int leader_update_ticket(struct ticket_config *tk)
	{
	int rv = 0;

	if (tk->ticket_updated >= 2)
	return 0;

	if (tk->ticket_updated < 1) {
	tk->ticket_updated = 1;
	tk->term_expires = time(NULL) + tk->term_duration;
	rv = ticket_broadcast(tk, OP_UPDATE, OP_ACK, RLT_SUCCESS, 0);
	}

	if (tk->ticket_updated < 2) {
	if (!ticket_dangerous(tk)) {
	tk->ticket_updated = 2;
	ticket_write(tk);
	} else {
	/* log just once, on the first retry */
	if (tk->retry_number == 1)
	tk_log_info("delaying ticket commit to CIB for %ds "
	"(or all sites are reached)",
	(int)(tk->delay_commit - time(NULL)));
	}
	}

	return rv;
	}


	static void log_lost_servers(struct ticket_config *tk)
	{
	struct booth_site *n;
	int i;

	if (tk->retry_number > 1)
	/* log those that we couldn't reach, but do
	* that only on the first retry
	*/
	return;

	for (i = 0; i < booth_conf->site_count; i++) {
	n = booth_conf->site + i;
	if (!(tk->acks_received & n->bitmask)) {
	tk_log_warn("%s %s didn't acknowledge our request, "
	"will retry %d times",
	(n->type == ARBITRATOR ? "arbitrator" : "site"),
	site_string(n),
	tk->retries);
	}
	}
	}

	static void resend_msg(struct ticket_config *tk)
	{
	struct booth_site *n;
	int i;

	if (!(tk->acks_received ^ local->bitmask)) {
	ticket_broadcast(tk, tk->last_request, 0, RLT_SUCCESS, 0);
	} else {
	for (i = 0; i < booth_conf->site_count; i++) {
	n = booth_conf->site + i;
	if (!(tk->acks_received & n->bitmask)) {
	tk_log_debug("resending %s to %s",
	state_to_string(tk->last_request),
	site_string(n)
	);
	send_msg(tk->last_request, tk, n, NULL);
	}
	}
	}
	}

	static void handle_resends(struct ticket_config *tk)
	{
	int ack_cnt;

	if (++tk->retry_number > tk->retries) {
	tk_log_debug("giving up on sending retries");
	no_resends(tk);
	set_ticket_wakeup(tk);
	return;
	}

	/* try to reach some sites again if we just stepped down */
	if (tk->last_request == OP_VOTE_FOR) {
	tk_log_warn("no answers to our request (try #%d), "
	"we are alone",
	tk->retry_number);
	goto just_resend;
	}

	if (!majority_of_bits(tk, tk->acks_received)) {
	ack_cnt = count_bits(tk->acks_received) - 1;
	if (!ack_cnt) {
	tk_log_warn("no answers to our request (try #%d), "
	"we are alone",
	tk->retry_number);
	} else {
	tk_log_warn("not enough answers to our request (try #%d): "
	"only got %d answers",
	tk->retry_number,
	ack_cnt);
	}
	} else {
	log_lost_servers(tk);
	if (tk->last_request == OP_HEARTBEAT &&
	is_owned(tk)) {
	/* we have the majority, update the ticket, at
	* least the local copy if we're still not
	* allowed to commit
	*/
	leader_update_ticket(tk);
	}
	}

	just_resend:
	resend_msg(tk);
	ticket_activate_timeout(tk);
	}

	int postpone_ticket_processing(struct ticket_config *tk)
	{
	extern time_t start_time;

	return tk->start_postpone &&
	((time(NULL) - start_time) < tk->timeout);
	}

	static void process_next_state(struct ticket_config *tk)
	{
	switch(tk->next_state) {
	case ST_LEADER:
	reacquire_ticket(tk);
	break;
	case ST_INIT:
	no_resends(tk);
	start_revoke_ticket(tk);
	break;
	/* wanting to be follower is not much of an ambition; no
	* processing, just return; don't reset start_postpone until
	* we got some replies to status */
	case ST_FOLLOWER:
	return;
	default:
	break;
	}
	tk->start_postpone = 0;
	}

	static void ticket_lost(struct ticket_config *tk)
	{
	if (tk->leader != local) {
	tk_log_warn("lost at %s", site_string(tk->leader));
	} else {
	tk_log_warn("lost majority (revoking locally)");
	}

	reset_ticket(tk);
	tk->state = ST_FOLLOWER;
	tk->lost_leader = tk->leader;
	if (local->type == SITE) {
	ticket_write(tk);
	schedule_election(tk, OR_TKT_LOST);
	}
	}

	static void next_action(struct ticket_config *tk)
	{
	switch(tk->state) {
	case ST_INIT:
	/* init state, handle resends for ticket revoke */
	/* and rebroadcast if stepping down */
	if (tk->acks_expected) {
	handle_resends(tk);
	}
	break;

	case ST_FOLLOWER:
	/* leader/ticket lost? and we didn't vote yet */
	tk_log_debug("leader: %s, voted_for: %s",
	site_string(tk->leader),
	site_string(tk->voted_for));
	if (!tk->leader && !tk->voted_for) {
	disown_ticket(tk);
	new_election(tk, NULL, 1, OR_AGAIN);
	}
	break;

	case ST_CANDIDATE:
	/* elections timed out? */
	elections_end(tk);
	break;

	case ST_LEADER:
	/* timeout or ticket renewal? */
	if (tk->acks_expected) {
	handle_resends(tk);
	} else {
	/* this is ticket renewal, run local test */
	if (!test_external_prog(tk, 1)) {
	ticket_broadcast(tk, OP_HEARTBEAT, OP_ACK, RLT_SUCCESS, 0);
	ticket_activate_timeout(tk);
	}
	}
	break;

	default:
	break;
	}
	}

	static void ticket_cron(struct ticket_config *tk)
	{
	time_t now;

	/* don't process the tickets too early after start */
	if (postpone_ticket_processing(tk)) {
	tk_log_debug("ticket processing postponed (start_postpone=%d)",
	tk->start_postpone);
	/* but run again soon */
	ticket_activate_timeout(tk);
	return;
	}

	/* no need for status resends, we hope we got at least one
	* my_index back */
	if (tk->acks_expected == OP_MY_INDEX) {
	no_resends(tk);
	}

	/* after startup, we need to decide what to do based on the
	* current ticket state; tk->next_state has a hint
	* also used for revokes which had to be delayed
	*/
	if (tk->next_state) {
	process_next_state(tk);
	goto out;
	}

	/* Has an owner, has an expiry date, and expiry date in the past?
	* Losing the ticket must happen in _every_ state. */
	now = time(NULL);
	if (!tk->in_election &&
	tk->term_expires &&
	is_owned(tk) &&
	now >= tk->term_expires) {
	ticket_lost(tk);
	goto out;
	}

	next_action(tk);

	out:
	tk->next_state = 0;
	- if (tk->update_cib)
	+ if (!tk->in_election && tk->update_cib)
	ticket_write(tk);
	}


	void process_tickets(void)
	{
	struct ticket_config *tk;
	int i;
	struct timeval now, last_cron;
	float sec_until;

	gettimeofday(&now, NULL);

	foreach_ticket(i, tk) {
	sec_until = timeval_to_float(tk->next_cron) - timeval_to_float(now);
	if (0)
	tk_log_debug("next cron %" PRIx64 ".%03d, "
	"now %" PRIx64 "%03d, in %f",
	(uint64_t)tk->next_cron.tv_sec, timeval_msec(tk->next_cron),
	(uint64_t)now.tv_sec, timeval_msec(now),
	sec_until);
	if (sec_until > 0.0)
	continue;

	tk_log_debug("ticket cron");


	last_cron = tk->next_cron;
	ticket_cron(tk);
	if (!timercmp(&last_cron, &tk->next_cron, !=)) {
	tk_log_debug("nobody set ticket wakeup");
	set_ticket_wakeup(tk);
	}
	}
	}



	void tickets_log_info(void)
	{
	struct ticket_config *tk;
	int i;

	foreach_ticket(i, tk) {
	tk_log_info("state '%s' "
	"term %d "
	"leader %s "
	"expires %-24.24s",
	state_to_string(tk->state),
	tk->current_term,
	ticket_leader_string(tk),
	ctime(&tk->term_expires));
	}
	}


	static void update_acks(
	struct ticket_config *tk,
	struct booth_site *sender,
	struct booth_site *leader,
	struct boothc_ticket_msg *msg
	)
	{
	uint32_t cmd;
	uint32_t req;

	cmd = ntohl(msg->header.cmd);
	req = ntohl(msg->header.request);
	if (req != tk->last_request \|\|
	(tk->acks_expected != cmd &&
	tk->acks_expected != OP_REJECTED))
	return;

	/* got an ack! */
	tk->acks_received \|= sender->bitmask;

	if (cmd == OP_HEARTBEAT)
	tk_log_debug("got ACK from %s, %d/%d agree.",
	site_string(sender),
	count_bits(tk->acks_received),
	booth_conf->site_count);

	if (tk->delay_commit && all_sites_replied(tk)) {
	tk->delay_commit = 0;
	}

	if (all_replied(tk) \|\|
	/* we just stepped down, need only one site to start
	* elections */
	(cmd == OP_REQ_VOTE && tk->last_request == OP_VOTE_FOR)) {
	no_resends(tk);
	tk->start_postpone = 0;
	set_ticket_wakeup(tk);
	}
	}

	/* UDP message receiver. */
	int message_recv(struct boothc_ticket_msg *msg, int msglen)
	{
	uint32_t from;
	struct booth_site *source;
	struct ticket_config *tk;
	struct booth_site *leader;
	uint32_t leader_u;


	if (check_boothc_header(&msg->header, sizeof(*msg)) < 0 \|\|
	msglen != sizeof(*msg)) {
	log_error("message receive error");
	return -1;
	}

	from = ntohl(msg->header.from);
	if (!find_site_by_id(from, &source) \|\| !source) {
	log_error("unknown sender: %08x", from);
	return -1;
	}

	if (!check_ticket(msg->ticket.id, &tk)) {
	log_warn("got invalid ticket name %s from %s",
	msg->ticket.id, site_string(source));
	return -EINVAL;
	}


	leader_u = ntohl(msg->ticket.leader);
	if (!find_site_by_id(leader_u, &leader)) {
	tk_log_error("message with unknown leader %u received", leader_u);
	return -EINVAL;
	}

	update_acks(tk, source, leader, msg);

	return raft_answer(tk, source, leader, msg);
	}


	static void log_next_wakeup(struct ticket_config *tk)
	{
	struct timeval now, res;

	gettimeofday(&now, NULL);
	timersub(&tk->next_cron, &now, &res);
	tk_log_debug("set ticket wakeup in %d.%06d",
	(int)res.tv_sec, (int)res.tv_usec);
	}

	/* New vote round; §5.2 */
	/* delay the next election start for up to 1s */
	void add_random_delay(struct ticket_config *tk)
	{
	struct timeval delay, tv;

	delay.tv_sec = 0;
	delay.tv_usec = cl_rand_from_interval(0, 1000000);
	timeradd(&tk->next_cron, &delay, &tv);
	ticket_next_cron_at(tk, tv);
	if (ANYDEBUG) {
	log_next_wakeup(tk);
	}
	}

	void set_ticket_wakeup(struct ticket_config *tk)
	{
	struct timeval tv, now;

	/* At least every hour, perhaps sooner. */
	ticket_next_cron_in(tk, 3600);
	gettimeofday(&now, NULL);

	switch (tk->state) {
	case ST_LEADER:
	assert(tk->leader == local);

	tv = now;
	tv.tv_sec = next_vote_starts_at(tk);

	/* If timestamp is in the past, wakeup at the expiry
	* time. */
	if (timeval_compare(tv, now) <= 0) {
	tk_log_debug("next ts in the past (%f)",
	timeval_to_float(tv) - timeval_to_float(now));
	tv.tv_sec = tk->term_expires;
	}

	ticket_next_cron_at(tk, tv);
	break;

	case ST_CANDIDATE:
	assert(tk->election_end);
	ticket_next_cron_at_coarse(tk, tk->election_end);
	break;

	case ST_INIT:
	case ST_FOLLOWER:
	/* If there is (or should be) some owner, check on it later on.
	* If no one is interested - don't care. */
	if (is_owned(tk) &&
	(local->type == SITE))
	ticket_next_cron_at_coarse(tk,
	tk->term_expires + tk->acquire_after);
	break;

	default:
	tk_log_error("unknown ticket state: %d", tk->state);
	}

	if (tk->next_state) {
	/* we need to do something soon here */
	if (!tk->acks_expected) {
	ticket_next_cron_at(tk, now);
	} else {
	ticket_activate_timeout(tk);
	}
	}

	if (ANYDEBUG) {
	log_next_wakeup(tk);
	}
	}


	void schedule_election(struct ticket_config *tk, cmd_reason_t reason)
	{
	if (local->type != SITE)
	return;

	tk->election_reason = reason;
	gettimeofday(&tk->next_cron, NULL);
	/* introduce a short delay before starting election */
	add_random_delay(tk);
	}



	/* Given a state (in host byte order), return a human-readable (char*).
	* An array is used so that multiple states can be printed in a single printf(). */
	char *state_to_string(uint32_t state_ho)
	{
	union mu { cmd_request_t s; char c[5]; };
	static union mu cache[6] = { { 0 } }, *cur;
	static int current = 0;

	current ++;
	if (current >= sizeof(cache)/sizeof(cache[0]))
	current = 0;

	cur = cache + current;

	cur->s = htonl(state_ho);
	/* Shouldn't be necessary, union array is initialized with zeroes, and
	* these bytes never get written. */
	cur->c[4] = 0;
	return cur->c;
	}


	int send_reject(struct booth_site dest, struct ticket_config tk,
	cmd_result_t code, struct boothc_ticket_msg *in_msg)
	{
	int req = ntohl(in_msg->header.cmd);
	struct boothc_ticket_msg msg;

	tk_log_debug("sending reject to %s",
	site_string(dest));
	init_ticket_msg(&msg, OP_REJECTED, req, code, 0, tk);
	return booth_udp_send(dest, &msg, sizeof(msg));
	}

	int send_msg (
	int cmd,
	struct ticket_config *current_tk,
	struct booth_site *dest,
	struct boothc_ticket_msg *in_msg
	)
	{
	int req = 0;
	struct ticket_config *tk = current_tk;
	struct boothc_ticket_msg msg;

	if (cmd == OP_MY_INDEX) {
	if (current_tk->state == ST_CANDIDATE &&
	current_tk->last_valid_tk->current_term) {
	tk = current_tk->last_valid_tk;
	}
	tk_log_info("sending status to %s",
	site_string(dest));
	}

	if (in_msg)
	req = ntohl(in_msg->header.cmd);

	init_ticket_msg(&msg, cmd, req, RLT_SUCCESS, 0, tk);
	return booth_udp_send(dest, &msg, sizeof(msg));
	}

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