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));
become_follower(tk, msg);
set_leader(tk, leader);
ticket_write(tk);
/* run ticket_cron if the ticket expires */
set_ticket_wakeup(tk);
return send_msg(OP_ACK, tk, sender, msg);
}
/** 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;
set_future_time(&tk->delay_commit, 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!");
time_reset(&tk->delay_commit);
}
rv = acquire_ticket(tk, OR_ADMIN);
if (rv) {
time_reset(&tk->delay_commit);
return rv;
} else {
return RLT_MORE;
}
}
/* 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);
}
/** 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)) {
if (is_manual(tk) && (options & OPT_IMMEDIATE)) {
/* -F flag has been used while granting a manual ticket.
* The ticket will be granted and may end up being granted
* on multiple sites */
tk_log_warn("manual ticket forced to be granted! be aware that "
"you may end up having two sites holding the same manual "
"ticket! revoke the ticket from the unnecessary site!");
} else {
return RLT_OVERGRANT;
}
}
set_future_time(&tk->delay_commit, 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!");
time_reset(&tk->delay_commit);
}
rv = acquire_ticket(tk, OR_ADMIN);
if (rv) {
time_reset(&tk->delay_commit);
return rv;
} else {
return RLT_MORE;
}
}
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));
/* don't process tickets with invalid term
*/
if (cmd != OP_STATUS &&
msg_term_invalid(tk, sender, leader, msg))
return 0;
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_INIT || tk->state == ST_FOLLOWER ||
tk->state == ST_CANDIDATE)) {
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;
}
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;
}
