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) {
set_state(tk, ST_FOLLOWER);
if (!in_election) {
set_leader(tk, 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;
}
/* 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;
/* Needed? */
newer_term(tk, sender, leader, msg, 0);
become_follower(tk, msg);
/* Racy??? */
assert(sender == leader || !leader);
set_leader(tk, leader);
/* Ack the heartbeat (we comply). */
return send_msg(OP_ACK, tk, sender, msg);
}
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;
time_t ts;
*pdata = NULL;
*len = 0;
alloc = booth_conf->ticket_count * (BOOTH_NAME_LEN * 2 + 128);
data = malloc(alloc);
if (!data)
return -ENOMEM;
cp = data;
foreach_ticket(i, tk) {
if (is_time_set(&tk->term_expires)) {
ts = wall_ts(&tk->term_expires);
strftime(timeout_str, sizeof(timeout_str), "%F %T",
localtime(&ts));
} else
strcpy(timeout_str, "INF");
if (tk->leader == local && is_time_set(&tk->delay_commit)
&& !is_past(&tk->delay_commit)) {
ts = wall_ts(&tk->delay_commit);
strcpy(pending_str, " (commit pending until ");
strftime(pending_str + strlen(" (commit pending until "),
sizeof(pending_str) - strlen(" (commit pending until ") - 1,
"%F %T", localtime(&ts));
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) {
free(data);
return -ENOMEM;
}
}
*pdata = data;
*len = cp - data;
return 0;
}
