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	diff --git a/src/ticket.c b/src/ticket.c
	index 27ddbe1..a488422 100644
	--- a/src/ticket.c
	+++ b/src/ticket.c
	@@ -1,904 +1,912 @@
	/*
	* 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 "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);
	}

	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)) {
	disown_ticket(tk);
	if (start_election) {
	ticket_broadcast(tk, OP_VOTE_FOR, 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;
	}


	/** Ticket revoke.
	* Only to be started from the leader. */
	int do_revoke_ticket(struct ticket_config *tk)
	{
	tk_log_info("revoking ticket");

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


	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, "INF");

	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, expires: %s, commit: %d%s\n",
	+ "ticket: %s, leader: %s",
	tk->name,
	- ticket_leader_string(tk),
	- timeout_str,
	- tk->commit_index,
	- pending_str);
	+ ticket_leader_string(tk));
	+
	+ if (is_owned(tk)) {
	+ cp += snprintf(cp,
	+ alloc - (cp - data),
	+ ", expires: %s, commit: %d%s\n",
	+ timeout_str,
	+ tk->commit_index,
	+ 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;
	}


	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->is_granted) {
	where_granted = "granted here";
	} else if (!valid) {
	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->leader != local) {
	if (tk->leader && tk->leader != no_leader) {
	tk_log_error("%s, but belongs to site %s, "
	"that's really too bad (will try to reacquire)",
	where_granted, site_string(tk->leader));
	} else {
	tk_log_warn("%s here, but we're "
	"not recorded as a grantee (will try to reacquire)",
	where_granted);
	}
	tk->leader = local;
	}
	if (!test_external_prog(tk, 1)) {
	/* try to acquire the
	* ticket through new elections
	*/
	acquire_ticket(tk, OR_REACQUIRE);
	}
	}

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

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

	if (local->type == SITE) {
	pcmk_handler.load_ticket(tk);
	}

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


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

	init_ticket_msg(&msg, cmd, 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));

	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->delay_commit = 0;
	return 0;
	}

	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)
	{
	struct boothc_ticket_msg msg;
	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;

	tk_log_debug("broadcasting ticket update");
	init_ticket_msg(&msg, OP_UPDATE, RLT_SUCCESS, 0, tk);
	rv = transport()->broadcast(&msg, sizeof(msg));
	}

	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;
	}


	void leader_elected(
	struct ticket_config *tk,
	struct booth_site *new_leader
	)
	{
	if (new_leader == local) {
	tk->leader = new_leader;

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

	tk_log_info("granted successfully here");
	tk->commit_index++;
	tk->state = ST_LEADER;
	send_heartbeat(tk);
	ticket_activate_timeout(tk);
	} else if (new_leader && new_leader != no_leader) {
	tk_log_error("%s is a new leader, strange",
	site_string(new_leader));
	}
	}


	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->acks_expected, 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->acks_expected),
	site_string(n)
	);
	send_msg(tk->acks_expected, tk, n);
	}
	}
	}
	}

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

	tk->retry_number ++;
	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 heartbeat (try #%d), "
	"we are alone",
	tk->retry_number);
	} else {
	tk_log_warn("not enough answers to heartbeat (try #%d): "
	"only got %d answers",
	tk->retry_number,
	ack_cnt);
	}
	} else {
	log_lost_servers(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);
	}

	if (tk->retry_number <= tk->retries) {
	resend_msg(tk);
	ticket_activate_timeout(tk);
	} else {
	tk_log_debug("giving up on sending retries");
	no_resends(tk);
	set_ticket_wakeup(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 ticket_cron(struct ticket_config *tk)
	{
	time_t now;
	struct booth_site *new_leader;

	now = time(NULL);

	/* don't process the tickets too early */
	if (postpone_ticket_processing(tk))
	return;

	if (tk->acks_expected == OP_MY_INDEX) {
	no_resends(tk);
	}

	if (tk->next_state) {
	if (tk->next_state == ST_LEADER) {
	if (tk->state == ST_LEADER) {
	new_round(tk, OR_SPLIT);
	} else {
	reacquire_ticket(tk);
	}
	}
	tk->next_state = 0;
	tk->start_postpone = 0;
	return;
	}

	/* Has an owner, has an expiry date, and expiry date in the past?
	* Losing the ticket must happen in _every_ state. */
	if (tk->term_expires &&
	is_owned(tk) &&
	now >= tk->term_expires) {

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

	tk->next_state = 0;
	/* Couldn't renew in time - ticket lost. */
	new_round(tk, OR_TKT_LOST);
	return;
	}

	switch(tk->state) {
	case ST_INIT:
	/* init state, nothing to do */
	break;

	case ST_FOLLOWER:
	/* nothing here either, ticket loss is caught earlier
	* */
	break;

	case ST_CANDIDATE:
	/* §5.2 */
	/* not everybody answered, but if we have majority... */
	new_leader = majority_votes(tk);
	if (new_leader) {
	leader_elected(tk, new_leader);
	} else if (now > tk->election_end) {
	/* This is previous election timed out */
	tk_log_info("election timed out");
	new_election(tk, NULL, 0, OR_AGAIN);
	}
	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)) {
	send_heartbeat(tk);
	ticket_activate_timeout(tk);
	}
	}
	break;

	default:
	break;
	}
	}


	void process_tickets(void)
	{
	struct ticket_config *tk;
	int i;
	struct timeval now;
	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");


	/* Set next value, handler may override.
	* This should already be handled via the state logic;
	* but to be on the safe side the renew repetition is
	* duplicated here, too. */
	set_ticket_wakeup(tk);

	ticket_cron(tk);
	}
	}



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

	foreach_ticket(i, tk) {
	tk_log_info("state '%s' "
	"term %d "
	"commit index %d "
	"leader %s "
	"expires %-24.24s",
	state_to_string(tk->state),
	tk->current_term,
	tk->commit_index,
	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;

	cmd = ntohl(msg->header.cmd);
	if (tk->acks_expected != cmd)
	return;

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

	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)) {
	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);
	}


	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, look again in one second. */
	if (timeval_compare(tv, now) <= 0)
	tv.tv_sec = now.tv_sec + 1;

	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 */
	ticket_activate_timeout(tk);
	}

	if (ANYDEBUG) {
	float sec_until;
	gettimeofday(&now, NULL);
	sec_until = timeval_to_float(tk->next_cron) - timeval_to_float(now);
	tk_log_debug("set ticket wakeup in %f", sec_until);
	}
	}



	/* 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 msg;

	init_ticket_msg(&msg, OP_REJECTED, code, 0, tk);
	return booth_udp_send(dest, &msg, sizeof(msg));
	}

	int send_msg (
	int cmd,
	struct ticket_config *tk,
	struct booth_site *dest
	)
	{
	struct boothc_ticket_msg msg;

	if (cmd == OP_MY_INDEX) {
	tk_log_info("sending status to %s",
	site_string(dest));
	}
	init_ticket_msg(&msg, cmd, RLT_SUCCESS, 0, tk);
	return booth_udp_send(dest, &msg, sizeof(msg));
	}

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