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	diff --git a/src/booth.h b/src/booth.h
	index edec609..5b0cc8c 100644
	--- a/src/booth.h
	+++ b/src/booth.h
	@@ -1,258 +1,258 @@
	/*
	* 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
	*/

	#ifndef _BOOTH_H
	#define _BOOTH_H

	#include <stdint.h>
	#include <sys/types.h>
	#include <sys/socket.h>
	#include <arpa/inet.h>
	#include <netinet/in.h>


	#define BOOTH_RUN_DIR "/var/run/booth/"
	#define BOOTH_LOG_DIR "/var/log"
	#define BOOTH_LOGFILE_NAME "booth.log"
	#define BOOTH_DEFAULT_CONF_DIR "/etc/booth/"
	#define BOOTH_DEFAULT_CONF_NAME "booth"
	#define BOOTH_DEFAULT_CONF_EXT ".conf"
	#define BOOTH_DEFAULT_CONF \
	BOOTH_DEFAULT_CONF_DIR BOOTH_DEFAULT_CONF_NAME BOOTH_DEFAULT_CONF_EXT

	#define DAEMON_NAME "boothd"
	#define BOOTH_PATH_LEN 127

	#define BOOTH_DEFAULT_PORT 9929

	/* TODO: remove */
	#define BOOTH_PROTO_FAMILY AF_INET

	#define BOOTHC_MAGIC 0x5F1BA08C
	#define BOOTHC_VERSION 0x00010002


	/** Timeout value for poll().
	* Determines frequency of periodic jobs, eg. when send-retries are done.
	* See process_tickets(). */
	#define POLL_TIMEOUT 1000


	/** @{ */
	/** The on-network data structures and constants. */

	#define BOOTH_NAME_LEN 64

	#define CHAR2CONST(a,b,c,d) ((a << 24) \| (b << 16) \| (c << 8) \| d)


	/* Says that the ticket shouldn't be active anywhere.
	* NONE wouldn't be specific enough. */
	#define NO_ONE ((uint32_t)-1)
	/* Says that another one should recover. */
	#define TICKET_LOST CHAR2CONST('L', 'O', 'S', 'T')


	typedef unsigned char boothc_site [BOOTH_NAME_LEN];
	typedef unsigned char boothc_ticket[BOOTH_NAME_LEN];


	struct boothc_header {
	/** Authentication data; not used now. */
	uint32_t iv;
	uint32_t auth1;
	uint32_t auth2;


	/** BOOTHC_MAGIC */
	uint32_t magic;
	/** BOOTHC_VERSION */
	uint32_t version;

	/** Packet source; site_id. See add_site(). */
	uint32_t from;

	/** Length including header */
	uint32_t length;

	/** The command respectively protocol state. See cmd_request_t. */
	uint32_t cmd;
	/** Result of operation. 0 == OK */
	uint32_t result;

	char data[0];
	} __attribute__((packed));


	struct ticket_msg {
	/** Ticket name. */
	boothc_ticket id;

	/** Current leader. May be NO_ONE. See add_site().
	* For a OP_REQ_VOTE this is */
	uint32_t leader;

	/** Current term. */
	uint32_t term;
	uint32_t term_valid_for;

	/* Perhaps we need to send a status along, too - like
	* starting, running, stopping, error, ...? */

	uint32_t leader_commit; // TODO: NEEDED?
	} __attribute__((packed));


	struct boothc_ticket_msg {
	struct boothc_header header;
	struct ticket_msg ticket;
	} __attribute__((packed));


	typedef enum {
	/* 0x43 = "C"ommands */
	CMD_LIST = CHAR2CONST('C', 'L', 's', 't'),
	CMD_GRANT = CHAR2CONST('C', 'G', 'n', 't'),
	CMD_REVOKE = CHAR2CONST('C', 'R', 'v', 'k'),

	/* Replies */
	CMR_GENERAL = CHAR2CONST('G', 'n', 'l', 'R'), // Increase distance to CMR_GRANT
	CMR_LIST = CHAR2CONST('R', 'L', 's', 't'),
	CMR_GRANT = CHAR2CONST('R', 'G', 'n', 't'),
	CMR_REVOKE = CHAR2CONST('R', 'R', 'v', 'k'),

	/* get status from another server */
	OP_STATUS = CHAR2CONST('S', 't', 'a', 't'),
	- OP_MY_INDEX = CHAR2CONST('M', 'I', 'd', 'x'), /* Answer to status */
	+ OP_MY_INDEX = CHAR2CONST('M', 'I', 'd', 'x'), /* reply to status */

	/* Raft */
	- OP_REQ_VOTE = CHAR2CONST('R', 'V', 'o', 't'),
	- OP_VOTE_FOR = CHAR2CONST('V', 't', 'F', 'r'),
	+ OP_REQ_VOTE = CHAR2CONST('R', 'V', 'o', 't'), /* start election */
	+ OP_VOTE_FOR = CHAR2CONST('V', 't', 'F', 'r'), /* reply to REQ_VOTE */
	OP_HEARTBEAT= CHAR2CONST('H', 'r', 't', 'B'), /* Heartbeat */
	OP_UPDATE = CHAR2CONST('U', 'p', 'd', 'E'), /* Update ticket */
	OP_REVOKE = CHAR2CONST('R', 'e', 'v', 'k'), /* Revoke ticket */
	OP_REJECTED = CHAR2CONST('R', 'J', 'C', '!'),
	} cmd_request_t;


	/* TODO: make readable constants */
	typedef enum {
	/* for compatibility with other functions */
	RLT_SUCCESS = 0,
	RLT_ASYNC = CHAR2CONST('A', 's', 'y', 'n'),
	RLT_SYNC_SUCC = CHAR2CONST('S', 'c', 'c', 's'),
	RLT_SYNC_FAIL = CHAR2CONST('F', 'a', 'i', 'l'),
	RLT_INVALID_ARG = CHAR2CONST('I', 'A', 'r', 'g'),
	RLT_EXT_FAILED = CHAR2CONST('X', 'P', 'r', 'g'),
	RLT_OVERGRANT = CHAR2CONST('O', 'v', 'e', 'r'),
	RLT_PROBABLY_SUCCESS = CHAR2CONST('S', 'u', 'c', '?'),
	RLT_BUSY = CHAR2CONST('B', 'u', 's', 'y'),
	RLT_TERM_OUTDATED = CHAR2CONST('T', 'O', 'd', 't'),
	RLT_TERM_STILL_VALID = CHAR2CONST('T', 'V', 'l', 'd'),
	RLT_REDIRECT = CHAR2CONST('R', 'e', 'd', 'r'),
	} cmd_result_t;


	/** @} */

	/** @{ */

	struct booth_site {
	/** Calculated ID. See add_site(). */
	int site_id;
	int type;
	int local;

	/** Roles, like ACCEPTOR, PROPOSER, or LEARNER. Not really used ATM. */
	int role;

	char addr_string[BOOTH_NAME_LEN];

	int tcp_fd;
	int udp_fd;

	/* 0-based, used for indexing into per-ticket weights */
	int index;
	uint64_t bitmask;

	unsigned short family;
	union {
	struct sockaddr_in sa4;
	struct sockaddr_in6 sa6;
	};
	int saddrlen;
	int addrlen;
	} __attribute__((packed));



	extern struct booth_site *local;
	extern struct booth_site * no_leader;

	/** @} */

	struct booth_transport;

	struct client {
	int fd;
	const struct booth_transport *transport;
	void (*workfn)(int);
	void (*deadfn)(int);
	};

	extern struct client *clients;
	extern struct pollfd *pollfds;


	int client_add(int fd, const struct booth_transport *tpt,
	void (workfn)(int ci), void (deadfn)(int ci));
	int do_read(int fd, void *buf, size_t count);
	int do_write(int fd, void *buf, size_t count);
	void process_connection(int ci);
	void safe_copy(char dest, char value, size_t buflen, const char *description);


	struct command_line {
	int type; /* ACT_ */
	int op; /* OP_ */
	char configfile[BOOTH_PATH_LEN];
	char lockfile[BOOTH_PATH_LEN];

	char site[BOOTH_NAME_LEN];
	struct boothc_ticket_msg msg;
	};
	extern struct command_line cl;



	/* http://gcc.gnu.org/onlinedocs/gcc/Typeof.html */
	#define min(a__,b__) \
	({ typeof (a__) _a = (a__); \
	typeof (b__) _b = (b__); \
	_a < _b ? _a : _b; })
	#define max(a__,b__) \
	({ typeof (a__) _a = (a__); \
	typeof (b__) _b = (b__); \
	_a > _b ? _a : _b; })





	#endif /* _BOOTH_H */
	diff --git a/src/config.h b/src/config.h
	index 9530006..5fb23a7 100644
	--- a/src/config.h
	+++ b/src/config.h
	@@ -1,191 +1,192 @@
	/*
	* 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
	*/

	#ifndef _CONFIG_H
	#define _CONFIG_H

	#include <stdint.h>
	#include "booth.h"
	#include "raft.h"
	#include "transport.h"


	/** @{ */
	/** Definitions for in-RAM data. */

	#define MAX_NODES 16
	#define TICKET_ALLOC 16



	struct ticket_config {
	/** \name Configuration items.
	* @{ */
	/** Name of ticket. */
	boothc_ticket name;

	/** How many seconds a term lasts (if not refreshed). */
	int term_duration;

	/** Network related timeouts. */
	int timeout;

	/** Retries before giving up. */
	int retries;

	/** If >0, time to wait for a site to get fenced.
	* The ticket may be acquired after that timespan by
	* another site. */
	int acquire_after; /* TODO: needed? */


	/* Program to ask whether it makes sense to
	* acquire the ticket */
	char *ext_verifier;

	/** Node weights. */
	int weight[MAX_NODES];
	/** @} */


	/** \name Runtime values.
	* @{ */
	/** Current state. */
	server_state_e state;

	/** When something has to be done */
	struct timeval next_cron;

	/** Current leader. This is effectively the log[] in Raft. */
	struct booth_site *leader;

	/** Is the ticket granted? */
	int is_granted;
	/** Timestamp of leadership expiration */
	time_t term_expires;
	/** End of election period */
	time_t election_end;
	struct booth_site *voted_for;


	/** Who the various sites vote for.
	* NO_OWNER = no vote yet. */
	struct booth_site *votes_for[MAX_NODES];
	/* bitmap */
	uint64_t votes_received;

	/** Last voting round that was seen. */
	uint32_t current_term;

	/** Do ticket updates whenever we get enough heartbeats.
	* But do that only once.
	* This is reset to 0 whenever we broadcast heartbeat and set
	* to 1 once enough acks are received.
	*/
	uint32_t majority_acks_received;
	/** @} */


	/** */
	uint32_t commit_index;

	/** */
	uint32_t last_applied;
	uint32_t next_index[MAX_NODES];
	uint32_t match_index[MAX_NODES];


	+ uint32_t acks_expected;
	uint64_t acks_received;
	- time_t hb_sent_at;
	+ time_t req_sent_at;

	/** \name Needed while proposals are being done.
	* @{ */
	/** Whom to vote for the next time.
	* Needed to push a ticket to someone else. */



	#if 0
	/** Bitmap of sites that acknowledge that state. */
	uint64_t proposal_acknowledges;

	/** When an incompletely acknowledged proposal gets done.
	* If all peers agree, that happens sooner.
	* See switch_state_to(). */
	struct timeval proposal_switch;

	/** Timestamp of proposal expiration. */
	time_t proposal_expires;

	#endif

	/** Number of send retries left.
	* Used on the new owner.
	* Starts at 0, counts up. */
	int retry_number;
	/** @} */
	};


	struct booth_config {
	char name[BOOTH_NAME_LEN];

	transport_layer_t proto;
	uint16_t port;

	/** Stores the OR of the individual host bitmasks. */
	uint64_t site_bits;

	char site_user[BOOTH_NAME_LEN];
	char site_group[BOOTH_NAME_LEN];
	char arb_user[BOOTH_NAME_LEN];
	char arb_group[BOOTH_NAME_LEN];
	uid_t uid;
	gid_t gid;

	int site_count;
	struct booth_site site[MAX_NODES];

	int ticket_count;
	int ticket_allocated;
	struct ticket_config *ticket;
	};


	extern struct booth_config *booth_conf;


	int read_config(const char *path);

	int check_config(int type);

	int find_site_by_name(unsigned char site, struct booth_site *node, int any_type);
	int find_site_by_id(uint32_t site_id, struct booth_site **node);

	const char *type_to_string(int type);


	#include <stdio.h>
	#define R(tk_) printf("## %12s:%3d state %s, %d:%d, " \
	"leader %s, exp %s", __FILE__, __LINE__, \
	state_to_string(tk_->state), tk_->current_term, \
	tk_->commit_index, site_string(tk_->leader), ctime(&tk_->term_expires))


	#endif /* _CONFIG_H */
	diff --git a/src/inline-fn.h b/src/inline-fn.h
	index aa6578b..f969fd8 100644
	--- a/src/inline-fn.h
	+++ b/src/inline-fn.h
	@@ -1,314 +1,320 @@
	/*
	* 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
	*/

	#ifndef _INLINE_FN_H
	#define _INLINE_FN_H

	#include <time.h>
	#include <sys/time.h>
	#include <assert.h>
	#include <string.h>
	#include "config.h"
	#include "ticket.h"
	#include "transport.h"



	inline static uint32_t get_local_id(void)
	{
	return local ? local->site_id : -1;
	}


	inline static uint32_t get_node_id(struct booth_site *node)
	{
	return node ? node->site_id : NO_ONE;
	}


	inline static int term_time_left(const struct ticket_config *tk)
	{
	int left;

	left = tk->term_expires - time(NULL);
	return (left < 0) ? 0 : left;
	}


	/** Returns number of seconds left, if any. */
	inline static int leader_and_valid(const struct ticket_config *tk)
	{
	if (tk->leader != local)
	return 0;

	return term_time_left(tk);
	}


	/** Is this some leader? */
	inline static int is_owned(const struct ticket_config *tk)
	{
	return (tk->leader && tk->leader != no_leader);
	}


	static inline void init_header_bare(struct boothc_header *h) {
	h->magic = htonl(BOOTHC_MAGIC);
	h->version = htonl(BOOTHC_VERSION);
	h->from = htonl(local->site_id);
	h->iv = htonl(0);
	h->auth1 = htonl(0);
	h->auth2 = htonl(0);
	}

	static inline void init_header(struct boothc_header *h, int cmd,
	int result, int data_len)
	{
	init_header_bare(h);
	h->length = htonl(data_len);
	h->cmd = htonl(cmd);
	h->result = htonl(result);
	}

	static inline void init_ticket_site_header(struct boothc_ticket_msg *msg, int cmd)
	{
	init_header(&msg->header, cmd, 0, sizeof(*msg));
	}

	static inline void init_ticket_msg(struct boothc_ticket_msg *msg,
	int cmd, int rv,
	struct ticket_config *tk)
	{
	assert(sizeof(msg->ticket.id) == sizeof(tk->name));

	init_header(&msg->header, cmd, rv, sizeof(*msg));

	if (!tk) {
	memset(&msg->ticket, 0, sizeof(msg->ticket));
	} else {
	memcpy(msg->ticket.id, tk->name, sizeof(msg->ticket.id));

	msg->ticket.leader = htonl(get_node_id(
	(tk->leader && tk->leader != no_leader) ? tk->leader : tk->voted_for));
	msg->ticket.term = htonl(tk->current_term);
	msg->ticket.term_valid_for = htonl(term_time_left(tk));

	msg->ticket.leader_commit = htonl(tk->commit_index);
	}
	}


	static inline struct booth_transport const *transport(void)
	{
	return booth_transport + booth_conf->proto;
	}


	static inline const char site_string(struct booth_site site)
	{
	return site ? site->addr_string : "NONE";
	}


	static inline const char ticket_leader_string(struct ticket_config tk)
	{
	return site_string(tk->leader);
	}


	static inline void disown_ticket(struct ticket_config *tk)
	{
	tk->leader = no_leader;
	tk->is_granted = 0;
	time(&tk->term_expires);
	}

	static inline int disown_if_expired(struct ticket_config *tk)
	{
	if (time(NULL) >= tk->term_expires \|\|
	!tk->leader) {
	disown_ticket(tk);
	return 1;
	}

	return 0;
	}



	/* We allow half of the uint32_t to be used;
	* half of that below, half of that above the current known "good" value.
	* 0 UINT32_MAX
	* \|--------------------------+----------------+------------\|
	* \| \| \|
	* \|--------+-------\| allowed range
	* \|
	* current commit index
	*
	* So, on overflow it looks like that:
	* UINT32_MAX 0
	* \|--------------------------+-----------\|\|---+------------\|
	* \| \| \|
	* \|--------+-------\| allowed range
	* \|
	* current commit index
	*
	* This should be possible by using the same datatype and relying
	* on the under/overflow semantics.
	*
	*
	* Having 30 bits available, and assuming an expire time of
	* one minute and a (high) commit index step of 64 == 2^6 (because
	* of weights), we get 2^24 minutes of range - which is ~750
	* years. "Should be enough for everybody."
	*/
	static inline int index_is_higher_than(uint32_t c_high, uint32_t c_low)
	{
	uint32_t diff;

	if (c_high == c_low)
	return 0;

	diff = c_high - c_low;
	if (diff < UINT32_MAX/4)
	return 1;

	diff = c_low - c_high;
	if (diff < UINT32_MAX/4)
	return 0;

	assert(!"commit index out of range - invalid");
	}


	static inline uint32_t index_max2(uint32_t a, uint32_t b)
	{
	return index_is_higher_than(a, b) ? a : b;
	}

	static inline uint32_t index_max3(uint32_t a, uint32_t b, uint32_t c)
	{
	return index_max2( index_max2(a, b), c);
	}


	static inline double timeval_to_float(struct timeval tv)
	{
	return tv.tv_sec + tv.tv_usec*(double)1.0e-6;
	}

	static inline int timeval_msec(struct timeval tv)
	{
	int m;

	m = tv.tv_usec / 1000;
	if (m >= 1000)
	m = 999;
	return m;
	}


	static inline int timeval_compare(struct timeval tv1, struct timeval tv2)
	{
	if (tv1.tv_sec < tv2.tv_sec)
	return -1;
	if (tv1.tv_sec > tv2.tv_sec)
	return +1;
	if (tv1.tv_usec < tv2.tv_usec)
	return -1;
	if (tv1.tv_usec > tv2.tv_usec)
	return +1;
	return 0;
	}


	static inline int timeval_in_past(struct timeval which)
	{
	struct timeval tv;

	gettimeofday(&tv, NULL);
	return timeval_compare(tv, which) > 0;
	}


	static inline time_t next_vote_starts_at(struct ticket_config *tk)
	{
	time_t half_exp, retries_needed;

	/* If not owner, don't renew. */
	if (tk->leader != local)
	return 0;

	/* Try to renew at half of expiry time. */
	half_exp = tk->term_expires - tk->term_duration/2;
	/* Also start renewal if we couldn't get
	* a few message retransmission in the alloted
	* expiry time. */
	retries_needed = tk->term_expires - tk->timeout * tk->retries/2;

	/* Return earlier timestamp. */
	return half_exp < retries_needed
	? half_exp
	: retries_needed;
	}


	static inline int should_start_renewal(struct ticket_config *tk)
	{
	time_t now, when;

	when = next_vote_starts_at(tk);
	if (!when)
	return 0;

	time(&now);
	return when <= now;
	}

	-
	-static inline int send_heartbeat(struct ticket_config *tk)
	+static inline void expect_replies(struct ticket_config *tk,
	+ int reply_type)
	{
	+ tk->acks_expected = reply_type;
	tk->acks_received = local->bitmask;
	- tk->hb_sent_at = time(NULL);
	+ tk->req_sent_at = time(NULL);
	tk->majority_acks_received = 0;
	+}
	+
	+static inline int send_heartbeat(struct ticket_config *tk)
	+{
	+ expect_replies(tk, OP_HEARTBEAT);

	return ticket_broadcast(tk, OP_HEARTBEAT, RLT_SUCCESS);
	}

	static inline struct booth_site my_vote(struct ticket_config tk)
	{
	return tk->votes_for[ local->index ];
	}


	static inline int count_bits(uint64_t val) {
	return __builtin_popcount(val);
	}

	static inline int majority_of_bits(struct ticket_config *tk, uint64_t val)
	{
	/* Use ">" to get majority decision, even for an even number
	* of participants. */
	return count_bits(val) * 2 >
	booth_conf->site_count;
	}




	#endif
	diff --git a/src/raft.c b/src/raft.c
	index d3265b5..dcfe2e7 100644
	--- a/src/raft.c
	+++ b/src/raft.c
	@@ -1,791 +1,770 @@
	/*
	* 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;

	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)
	{
	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)
	log_warn("voted previously (but in same term!) for %s...",
	site_string(tk->votes_for[who->index]));
	}
	}


	static int cmp_msg_ticket(struct ticket_config *tk,
	struct boothc_ticket_msg *msg)
	{
	if (tk->current_term != ntohl(msg->ticket.term)) {
	return tk->current_term - ntohl(msg->ticket.term);
	}
	return tk->commit_index - ntohl(msg->ticket.leader_commit);
	}

	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);
	}

	/* § 5.3 */
	i = ntohl(msg->ticket.leader_commit);
	tk->commit_index = max(i, tk->commit_index);
	}


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


	duration = tk->term_duration;
	if (msg)
	duration = min(duration, ntohl(msg->ticket.term_valid_for));
	tk->term_expires = time(NULL) + duration;


	if (msg) {
	update_term_from_msg(tk, msg);
	}
	}

	static void become_follower(struct ticket_config *tk,
	struct boothc_ticket_msg *msg)
	{
	update_ticket_from_msg(tk, msg);
	tk->state = ST_FOLLOWER;
	}


	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]++;
	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;


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

	return NULL;
	}


	-static int all_voted(struct ticket_config *tk)
	-{
	- int i, cnt = 0;
	-
	- for(i=0; i<booth_conf->site_count; i++) {
	- if (tk->votes_for[i]) {
	- cnt++;
	- }
	- }
	-
	- return (cnt == booth_conf->site_count);
	-}
	-
	-
	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;

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

	tk->term_expires = time(NULL) + tk->term_duration;
	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) {
	log_info("sending reject to %s, its term too low "
	"(%d vs. %d)", site_string(leader),
	term, tk->current_term
	);
	send_reject(sender, tk, RLT_TERM_OUTDATED);
	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;
	struct boothc_ticket_msg omsg;


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

	/* if we're candidate, it may be that we got a heartbeat from
	* a legitimate leader, so don't ignore a lower term
	*/
	if (tk->state != ST_CANDIDATE && term < tk->current_term) {
	log_info("ignoring lower term %d vs. %d, from %s",
	term, tk->current_term,
	ticket_leader_string(tk));
	return 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). */
	init_ticket_msg(&omsg, OP_HEARTBEAT, RLT_SUCCESS, tk);
	return booth_udp_send(sender, &omsg, sizeof(omsg));
	}


	static int process_UPDATE (
	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);
	log_debug("leader: %s, have %s; term %d vs %d",
	site_string(leader), ticket_leader_string(tk),
	term, tk->current_term);

	/* No reject. (?) */
	if (term < tk->current_term) {
	log_info("ignoring lower term %d vs. %d, from %s",
	term, tk->current_term,
	ticket_leader_string(tk));
	return 0;
	}

	update_ticket_from_msg(tk, msg);
	ticket_write(tk);

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

	return 0;
	}

	static int process_REVOKE (
	struct ticket_config *tk,
	struct booth_site *sender,
	struct booth_site *leader,
	struct boothc_ticket_msg *msg
	)
	{
	if (tk->leader != sender) {
	log_error("from %s: non-leader wants to revoke ticket %s (ignoring)",
	site_string(sender), tk->name);
	return 1;
	} else if (tk->state != ST_FOLLOWER) {
	log_error("from %s: unexpected ticket %s revoke in state %s (ignoring)",
	site_string(sender),
	state_to_string(tk->state),
	tk->name);
	return 1;
	} else {
	log_info("from %s: leader revokes ticket %s",
	site_string(sender), tk->name);
	reset_ticket(tk);
	ticket_write(tk);
	}

	return 0;
	}

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

	tk->term_expires = time(NULL) + tk->term_duration;
	tk->retry_number = 0;
	ticket_write(tk);
	set_ticket_wakeup(tk);
	init_ticket_msg(&msg, OP_UPDATE, RLT_SUCCESS, tk);
	return transport()->broadcast(&msg, sizeof(msg));
	}

	/* For leader. */
	static int process_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);

	if (newer_term(tk, sender, leader, msg, 0)) {
	/* unexpected higher term */
	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? */
	log_warn("from %s: unexpected "
	"term %d instead of %d (ignoring)",
	site_string(sender),
	term, tk->current_term);
	return 0;
	}


	if (term == tk->current_term &&
	leader == tk->leader) {
	- /* got an ack! */
	- tk->acks_received \|= sender->bitmask;
	-
	- log_debug("got heartbeat ACK from %s, %d/%d agree.",
	- site_string(sender),
	- count_bits(tk->acks_received),
	- booth_conf->site_count);
	-

	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
	*/
	if( !tk->majority_acks_received ) {
	/* Write the ticket to the CIB and set the next
	* wakeup time (but do that only once) */
	tk->majority_acks_received = 1;
	return leader_update_ticket(tk);
	}
	}
	}

	return 0;
	}


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

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

	if (new_leader == local) {
	tk->commit_index++;
	tk->state = ST_LEADER;
	send_heartbeat(tk);
	ticket_activate_timeout(tk);
	} else {
	become_follower(tk, NULL);
	set_ticket_wakeup(tk);
	}
	}
	}


	static int process_VOTE_FOR(
	struct ticket_config *tk,
	struct booth_site *sender,
	struct booth_site *leader,
	struct boothc_ticket_msg *msg
	)
	{
	if (term_too_low(tk, sender, leader, msg))
	return 0;

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


	/* leader wants to step down? */
	if (leader == no_leader && sender == tk->leader &&
	(tk->state == ST_FOLLOWER \|\| tk->state == ST_CANDIDATE)) {
	log_info("ticket %s owner %s wants to step down",
	tk->name, site_string(tk->leader));
	return new_round(tk);
	}

	record_vote(tk, sender, leader);


	if (tk->state != ST_CANDIDATE) {
	/* lost candidate status, somebody rejected our proposal */
	return 0;
	}


	/* only if all voted can we take the ticket now, otherwise
	* wait for timeout in ticket_cron */
	- if (all_voted(tk)) {
	+ if (!tk->acks_expected) {
	/* §5.2 */
	leader_elected(tk, majority_votes(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 &&
	rv == RLT_TERM_OUTDATED) {
	log_warn("from %s: ticket %s outdated (term %d), following %s",
	site_string(sender),
	tk->name, ntohl(msg->ticket.term),
	site_string(leader)
	);
	tk->leader = leader;
	become_follower(tk, msg);
	return 0;
	}


	if (tk->state == ST_CANDIDATE &&
	rv == RLT_TERM_STILL_VALID) {
	log_warn("from %s: there's a leader I didn't see: %s, following",
	site_string(sender),
	site_string(leader));
	tk->leader = leader;
	become_follower(tk, msg);
	return 0;
	}

	log_warn("from %s: in state %s, got %s (unexpected reject)",
	site_string(sender),
	state_to_string(tk->state),
	state_to_string(rv));
	tk->leader = leader;
	become_follower(tk, msg);
	return 0;
	}


	static int send_ticket (
	int cmd,
	struct ticket_config *tk,
	struct booth_site *to_site
	)
	{
	struct boothc_ticket_msg omsg;


	init_ticket_msg(&omsg, cmd, RLT_SUCCESS, tk);
	return booth_udp_send(to_site, &omsg, sizeof(omsg));
	}


	/* §5.2 */
	static int answer_REQ_VOTE(
	struct ticket_config *tk,
	struct booth_site *sender,
	struct booth_site *leader,
	struct boothc_ticket_msg *msg
	)
	{
	uint32_t term;
	int valid;
	struct boothc_ticket_msg omsg;


	term = ntohl(msg->ticket.term);
	/* Important: Ignore duplicated packets! */
	valid = term_time_left(tk);
	if (valid &&
	term == tk->current_term &&
	sender == tk->leader) {
	log_debug("Duplicate OP_VOTE_FOR ignored.");
	return 0;
	}

	if (valid) {
	log_warn("no election allowed for %s, term still valid for %d",
	tk->name, valid);
	return send_reject(sender, tk, RLT_TERM_STILL_VALID);
	}

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

	/* 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, RLT_SUCCESS, 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)
	{
	struct booth_site *new_leader;
	time_t now;


	time(&now);
	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)
	tk->current_term++;

	tk->term_expires = 0;
	tk->election_end = now + tk->term_duration;

	log_info("starting new election, term=%d, until %" PRIi64,
	tk->current_term, (int64_t)tk->election_end);
	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->state = ST_CANDIDATE;

	+ expect_replies(tk, OP_VOTE_FOR);
	ticket_broadcast(tk, OP_REQ_VOTE, RLT_SUCCESS);
	ticket_activate_timeout(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
	)
	{
	if (leader == no_leader \|\| !leader \|\| leader == local) {
	/* at least nobody else owns the ticket */
	/* it is not kosher to update from their copy, but since
	* they don't own the ticket, nothing bad can happen
	*/
	update_term_from_msg(tk, msg);
	/* get the ticket again, if we can
	*/
	return acquire_ticket(tk);
	}

	/* eek, two leaders, split brain */
	/* normally shouldn't happen; run election */
	log_error("from %s: ticket %s at %s! (disowning ticket)",
	site_string(sender),
	tk->name, site_string(leader)
	);
	log_error("Two ticket owners! Possible bug. Please report at https://github.com/ClusterLabs/booth/issues/new.");
	return new_round(tk);
	}

	/* 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 rv;

	if (!msg->ticket.term_valid_for) {
	/* ticket not valid */
	return 0;
	}

	i = cmp_msg_ticket(tk, msg);

	if (i > 0) {
	/* let them know about our newer ticket */
	send_ticket(OP_MY_INDEX, tk, sender);
	if (tk->state == ST_LEADER)
	return send_ticket(OP_UPDATE, tk, sender);
	}

	if (i == 0) {
	return 0;
	}

	/* they have a newer ticket, trouble if we're already leader
	* for it */
	if (tk->state == ST_LEADER) {
	log_warn("from %s: more uptodate ticket %s at %s",
	site_string(sender),
	tk->name,
	site_string(leader)
	);
	return leader_handle_newer_ticket(tk, sender, leader, msg);
	}

	update_ticket_from_msg(tk, msg);
	tk->leader = leader;
	if (leader == local) {
	rv = test_external_prog(tk, 1);
	if (!rv) {
	/* if we were the leader but we rebooted in the
	* meantime; try to get the ticket again
	*/
	tk->state = ST_LEADER;
	rv = send_heartbeat(tk);
	ticket_activate_timeout(tk);
	}
	return rv;
	} else {
	tk->state = (!leader \|\| leader == no_leader) ?
	ST_INIT : ST_FOLLOWER;
	}
	return 0;
	}


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

	rv = 0;
	cmd = ntohl(msg->header.cmd);
	R(tk);

	log_debug("got message %s from %s",
	state_to_string(cmd),
	site_string(from));


	switch (cmd) {
	case OP_REQ_VOTE:
	rv = answer_REQ_VOTE(tk, from, leader, msg);
	break;
	case OP_VOTE_FOR:
	rv = process_VOTE_FOR(tk, from, leader, msg);
	break;
	case OP_HEARTBEAT:
	if (tk->leader == local &&
	tk->state == ST_LEADER)
	rv = process_HEARTBEAT(tk, from, leader, msg);
	else if (tk->leader != local &&
	(tk->state == ST_FOLLOWER \|\|
	tk->state == ST_CANDIDATE))
	rv = answer_HEARTBEAT(tk, from, leader, msg);
	else {
	log_warn("unexpected message %s, from %s",
	state_to_string(cmd),
	site_string(from));
	rv = -EINVAL;
	}
	break;
	case OP_UPDATE:
	if (tk->leader != local && tk->state == ST_FOLLOWER) {
	rv = process_UPDATE(tk, from, leader, msg);
	} else {
	log_warn("unexpected message %s, from %s",
	state_to_string(cmd),
	site_string(from));
	rv = -EINVAL;
	}
	break;
	case OP_REJECTED:
	rv = process_REJECTED(tk, from, leader, msg);
	break;
	case OP_REVOKE:
	rv = process_REVOKE(tk, from, leader, msg);
	break;
	case OP_MY_INDEX:
	rv = process_MY_INDEX(tk, from, leader, msg);
	break;
	case OP_STATUS:
	rv = send_ticket(OP_MY_INDEX, tk, from);
	break;
	default:
	log_error("unknown message %s, from %s",
	state_to_string(cmd), site_string(from));
	rv = -EINVAL;
	}
	R(tk);
	return rv;
	}
	diff --git a/src/ticket.c b/src/ticket.c
	index 03cc3c1..f11ea38 100644
	--- a/src/ticket.c
	+++ b/src/ticket.c
	@@ -1,664 +1,697 @@
	/*
	* 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;
	}


	#if 0
	/** Find out what others think about this ticket.
	*
	* If we're a SITE, we can ask (and have to tell) Pacemaker.
	* An ARBITRATOR can only ask others. */
	static int ticket_send_catchup(struct ticket_config *tk)
	{
	int i, rv = 0;
	struct booth_site *site;
	struct boothc_ticket_msg msg;

	foreach_node(i, site) {
	if (!site->local) {
	init_ticket_msg(&msg, CMD_CATCHUP, RLT_SUCCESS, tk);

	log_debug("attempting catchup from %s", site->addr_string);

	rv = booth_udp_send(site, &msg, sizeof(msg));
	}
	}

	ticket_activate_timeout(tk);

	return rv;
	}
	#endif


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

	disown_if_expired(tk);

	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) {
	log_warn("we are not allowed to acquire ticket %s",
	tk->name);

	/* Give it to somebody else.
	- * Just send a commit message, as the
	- * others couldn't help anyway. */
	+ * 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);
	}
	}
	}

	return rv;
	}


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

	return new_election(tk, local, 1);
	}


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

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

	rv = acquire_ticket(tk);
	return rv;
	}


	/** Ticket revoke.
	* Only to be started from the leader. */
	int do_revoke_ticket(struct ticket_config *tk)
	{
	log_info("revoking ticket %s", tk->name);

	reset_ticket(tk);
	ticket_write(tk);
	return ticket_broadcast(tk, OP_REVOKE, RLT_SUCCESS);
	}


	int list_ticket(char *pdata, unsigned int len)
	{
	struct ticket_config *tk;
	char timeout_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");


	cp += sprintf(cp,
	"ticket: %s, leader: %s, expires: %s, commit: %d\n",
	tk->name,
	ticket_leader_string(tk),
	timeout_str,
	tk->commit_index);

	*len = cp - data;
	assert(*len < alloc);
	}

	*pdata = data;

	return 0;
	}

	void reset_ticket(struct ticket_config *tk)
	{
	disown_ticket(tk);
	tk->current_term = 0;
	tk->commit_index = 0;
	tk->state = ST_INIT;
	}


	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);
	if (time(NULL) >= tk->term_expires) {
	reset_ticket(tk);
	ticket_write(tk);
	}
	}


	/* if the ticket is uptodate and belongs to us, try with
	* the heartbeat
	*/
	if (tk->is_granted && tk->leader == local) {
	if (!test_external_prog(tk, 1)) {
	tk->state = ST_LEADER;
	send_heartbeat(tk);
	ticket_activate_timeout(tk);
	}
	} else {
	/* otherwise, query status */
	ticket_broadcast(tk, OP_STATUS, RLT_SUCCESS);
	}
	}

	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, RLT_SUCCESS, 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);

	reply:
	init_header(&msg->header, CMR_GRANT, rv ?: RLT_ASYNC, 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);
	/* Return a different result code? */
	rv = RLT_SUCCESS;
	goto reply;
	}

	if (tk->leader != local) {
	log_info("we do not own the ticket %s, "
	"redirect to leader %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, tk);
	return send_ticket_msg(fd, msg);
	}


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

	init_ticket_msg(&msg, cmd, res, tk);
	log_debug("broadcasting '%s' for ticket %s (term=%d, valid=%d)",
	state_to_string(cmd), tk->name,
	ntohl(msg.ticket.term),
	ntohl(msg.ticket.term_valid_for));

	return transport()->broadcast(&msg, sizeof(msg));
	}


	int new_round(struct ticket_config *tk)
	{
	int rv = 0;

	disown_ticket(tk);

	/* New vote round; §5.2 */
	if (local->type == SITE) {
	rv = new_election(tk, NULL, 1);
	ticket_write(tk);
	}

	return rv;
	}


	static void ticket_cron(struct ticket_config *tk)
	{
	time_t now;
	int vote_cnt;
	struct booth_site *new_leader;

	now = time(NULL);


	R(tk);
	/* 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) {

	log_warn("LOST ticket: %s no longer at %s",
	tk->name,
	ticket_leader_string(tk));

	/* Couldn't renew in time - ticket lost. */
	new_round(tk);
	return;
	}
	R(tk);

	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 */
	new_election(tk, NULL, 0);
	}
	break;

	case ST_LEADER:
	/* we get here after we broadcasted a heartbeat;
	* by this time all sites should've acked the heartbeat
	*/
	- vote_cnt = count_bits(tk->acks_received) - 1;
	- if ((vote_cnt+1) < booth_conf->site_count) {
	+ if (tk->acks_expected) {
	if (!majority_of_bits(tk, tk->acks_received)) {
	tk->retry_number ++;
	+ vote_cnt = count_bits(tk->acks_received) - 1;
	if (!vote_cnt) {
	log_warn("no answers to heartbeat for ticket %s on try #%d, "
	"we are alone",
	tk->name,
	tk->retry_number);
	} else {
	log_warn("not enough answers to heartbeat for ticket %s on try #%d: "
	"only got %d answers",
	tk->name,
	tk->retry_number,
	vote_cnt);
	}
	/* Don't give up, though - there's still some time until leadership is lost. */
	}
	}

	send_heartbeat(tk);
	if (tk->retry_number < tk->retries) {
	ticket_activate_timeout(tk);
	} else {
	set_ticket_wakeup(tk);
	}
	break;

	default:
	break;
	}
	R(tk);
	}


	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)
	log_debug("ticket %s next cron %" PRIx64 ".%03d, "
	"now %" PRIx64 "%03d, in %f",
	tk->name,
	(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;

	log_debug("ticket cron: doing %s", tk->name);


	/* 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) {
	log_info("Ticket %s: state '%s' "
	"commit index %d "
	"leader %s "
	"expires %-24.24s",
	tk->name,
	state_to_string(tk->state),
	tk->commit_index,
	ticket_leader_string(tk),
	ctime(&tk->term_expires));
	}
	}


	+static int all_replied(struct ticket_config *tk)
	+{
	+ return (count_bits(tk->acks_received) == booth_conf->site_count);
	+}
	+
	+
	+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;
	+
	+ log_debug("got ACK from %s, %d/%d agree.",
	+ site_string(sender),
	+ count_bits(tk->acks_received),
	+ booth_conf->site_count);
	+
	+ if (all_replied(tk)) {
	+ tk->acks_expected = 0;
	+ }
	+}
	+
	/* 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)) {
	log_error("Message with unknown owner %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);

	switch (tk->state) {
	case ST_LEADER:
	assert(tk->leader == local);
	gettimeofday(&now, NULL);

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



	/* 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, tk);
	return booth_udp_send(dest, &msg, sizeof(msg));
	}

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