/* ----------
* slon_localListenThread
*
* Listen for events on the local database connection. This means,
* events generated by the local node only.
* ----------
*/
void *
localListenThread_main(/* @unused@ */ void *dummy)
{
SlonConn *conn;
SlonDString query1;
PGconn *dbconn;
PGresult *res;
int ntuples;
int tupno;
PGnotify *notification;
char restart_notify[256];
int restart_request;
int poll_sleep = 0;
int node_lock_obtained=0;
slon_log(SLON_INFO, "localListenThread: thread starts\n");
/*
* Connect to the local database
*/
if ((conn = slon_connectdb(rtcfg_conninfo, "local_listen")) == NULL)
slon_retry();
dbconn = conn->dbconn;
/*
* Initialize local data
*/
dstring_init(&query1);
sprintf(restart_notify, "_%s_Restart", rtcfg_cluster_name);
/*
* Listen for local events
*/
(void) slon_mkquery(&query1,
"listen \"_%s_Restart\"; ",
rtcfg_cluster_name);
res = PQexec(dbconn, dstring_data(&query1));
if (PQresultStatus(res) != PGRES_COMMAND_OK)
{
slon_log(SLON_FATAL,
"localListenThread: \"%s\" - %s\n",
dstring_data(&query1), PQresultErrorMessage(res));
PQclear(res);
dstring_free(&query1);
pthread_mutex_lock(&slon_wait_listen_lock);
slon_listen_started=0;
pthread_cond_signal(&slon_wait_listen_cond);
pthread_mutex_unlock(&slon_wait_listen_lock);
slon_retry();
}
PQclear(res);
/*
* Check that we are the only slon daemon connected.
*/
#define NODELOCKERROR "ERROR: duplicate key violates unique constraint \"sl_nodelock-pkey\""
(void) slon_mkquery(&query1,
"select %s.cleanupNodelock(); "
"insert into %s.sl_nodelock values ("
" %d, 0, \"pg_catalog\".pg_backend_pid()); ",
rtcfg_namespace, rtcfg_namespace,
rtcfg_nodeid);
while(!node_lock_obtained)
{
res = PQexec(dbconn, dstring_data(&query1));
if (PQresultStatus(res) != PGRES_COMMAND_OK)
{
slon_log(SLON_FATAL,
"localListenThread: \"%s\" - %s\n",
dstring_data(&query1), PQresultErrorMessage(res));
if (strncmp(NODELOCKERROR, PQresultErrorMessage(res), strlen(NODELOCKERROR)) == 0) {
slon_log(SLON_FATAL,
"Do you already have a slon running against this node?\n");
slon_log(SLON_FATAL,
"Or perhaps a residual idle backend connection from a dead slon?\n");
PQclear(res);
if(worker_restarted)
{
sleep(5);
continue;
}
else
{
dstring_free(&query1);
pthread_mutex_lock(&slon_wait_listen_lock);
slon_listen_started=0;
pthread_cond_signal(&slon_wait_listen_cond);
pthread_mutex_unlock(&slon_wait_listen_lock);
slon_abort();
}
}
PQclear(res);
dstring_free(&query1);
slon_abort();
}
PQclear(res);
node_lock_obtained=1;
}
/*
* Flag the main thread that the coast is clear and he can launch all
* other threads.
*/
pthread_mutex_lock(&slon_wait_listen_lock);
slon_listen_started=1;
pthread_cond_signal(&slon_wait_listen_cond);
pthread_mutex_unlock(&slon_wait_listen_lock);
/*
* Process all events, then wait for notification and repeat until
* shutdown time has arrived.
*/
while (true)
{
/*
* Start the transaction
*/
res = PQexec(dbconn, "start transaction; "
"set transaction isolation level serializable;");
if (PQresultStatus(res) != PGRES_COMMAND_OK)
{
slon_log(SLON_FATAL,
"localListenThread: cannot start transaction - %s\n",
PQresultErrorMessage(res));
PQclear(res);
dstring_free(&query1);
slon_retry();
break;
}
PQclear(res);
/*
* Drain notifications.
*/
(void) PQconsumeInput(dbconn);
restart_request = false;
while ((notification = PQnotifies(dbconn)) != NULL)
{
if (strcmp(restart_notify, notification->relname) == 0)
restart_request = true;
(void) PQfreemem(notification);
}
if (restart_request)
{
slon_log(SLON_INFO,
"localListenThread: got restart notification\n");
#ifndef WIN32
slon_restart();
#else
/* XXX */
/* Win32 defer to service manager to restart for now */
slon_restart();
#endif
}
/*
* Query the database for new local events
*/
(void) slon_mkquery(&query1,
"select ev_seqno, ev_timestamp, "
" 'dummy', 'dummy', 'dummy', "
" ev_type, "
" ev_data1, ev_data2, ev_data3, ev_data4, "
" ev_data5, ev_data6, ev_data7, ev_data8 "
"from %s.sl_event "
"where ev_origin = '%d' "
" and ev_seqno > '%s' "
"order by ev_seqno",
rtcfg_namespace, rtcfg_nodeid, rtcfg_lastevent);
res = PQexec(dbconn, dstring_data(&query1));
if (PQresultStatus(res) != PGRES_TUPLES_OK)
{
slon_log(SLON_FATAL,
"localListenThread: \"%s\" - %s\n",
dstring_data(&query1), PQresultErrorMessage(res));
PQclear(res);
dstring_free(&query1);
slon_retry();
break;
}
ntuples = PQntuples(res);
for (tupno = 0; tupno < ntuples; tupno++)
{
char *ev_type;
/*
* Remember the event sequence number for confirmation
*/
strcpy(rtcfg_lastevent, PQgetvalue(res, tupno, 0));
/*
* Get the event type and process configuration events
*/
ev_type = PQgetvalue(res, tupno, 5);
slon_log(SLON_DEBUG2, "localListenThread: "
"Received event %d,%s %s\n",
rtcfg_nodeid, PQgetvalue(res, tupno, 0),
ev_type);
if (strcmp(ev_type, "SYNC") == 0)
{
/*
* SYNC - nothing to do
*/
}
else if (strcmp(ev_type, "STORE_NODE") == 0)
{
/*
* STORE_NODE
*/
int no_id;
char *no_comment;
no_id = (int)strtol(PQgetvalue(res, tupno, 6), NULL, 10);
no_comment = PQgetvalue(res, tupno, 7);
if (no_id != rtcfg_nodeid)
rtcfg_storeNode(no_id, no_comment);
rtcfg_reloadListen(dbconn);
}
else if (strcmp(ev_type, "ENABLE_NODE") == 0)
{
/*
* ENABLE_NODE
*/
int no_id;
no_id = (int)strtol(PQgetvalue(res, tupno, 6), NULL, 10);
if (no_id != rtcfg_nodeid)
rtcfg_enableNode(no_id);
rtcfg_reloadListen(dbconn);
}
else if (strcmp(ev_type, "DROP_NODE") == 0)
{
/*
* DROP_NODE
*/
int no_id;
char notify_query[256];
PGresult *notify_res;
no_id = (int)strtol(PQgetvalue(res, tupno, 6), NULL, 10);
/*
* Deactivate the node in the runtime configuration
*/
rtcfg_disableNode(no_id);
/*
* And cause the replication daemon to restart to get rid of
* it.
*/
snprintf(notify_query, sizeof(notify_query),
"notify \"_%s_Restart\";",
rtcfg_cluster_name);
notify_res = PQexec(dbconn, notify_query);
if (PQresultStatus(notify_res) != PGRES_COMMAND_OK)
{
slon_log(SLON_FATAL, "localListenThread: \"%s\" %s\n",
notify_query, PQresultErrorMessage(notify_res));
PQclear(notify_res);
slon_restart();
}
PQclear(notify_res);
rtcfg_reloadListen(dbconn);
}
else if (strcmp(ev_type, "CLONE_NODE") == 0)
{
/*
* CLONE_NODE
*/
int no_id;
int no_provider;
char *no_comment;
no_id = (int)strtol(PQgetvalue(res, tupno, 6), NULL, 10);
no_provider = (int)strtol(PQgetvalue(res, tupno, 7), NULL, 10);
no_comment = PQgetvalue(res, tupno, 8);
rtcfg_storeNode(no_id, no_comment);
}
else if (strcmp(ev_type, "STORE_PATH") == 0)
{
/*
* STORE_PATH
*/
int pa_server;
int pa_client;
char *pa_conninfo;
int pa_connretry;
pa_server = (int)strtol(PQgetvalue(res, tupno, 6), NULL, 10);
pa_client = (int)strtol(PQgetvalue(res, tupno, 7), NULL, 10);
pa_conninfo = PQgetvalue(res, tupno, 8);
pa_connretry = (int)strtol(PQgetvalue(res, tupno, 9), NULL, 10);
if (pa_client == rtcfg_nodeid)
rtcfg_storePath(pa_server, pa_conninfo, pa_connretry);
rtcfg_reloadListen(dbconn);
}
else if (strcmp(ev_type, "DROP_PATH") == 0)
{
/*
* DROP_PATH
*/
int pa_server;
int pa_client;
pa_server = (int)strtol(PQgetvalue(res, tupno, 6), NULL, 10);
pa_client = (int)strtol(PQgetvalue(res, tupno, 7), NULL, 10);
if (pa_client == rtcfg_nodeid)
rtcfg_dropPath(pa_server);
rtcfg_reloadListen(dbconn);
}
else if (strcmp(ev_type, "STORE_LISTEN") == 0)
{
/*
* STORE_LISTEN
*/
int li_origin;
int li_provider;
int li_receiver;
li_origin = (int)strtol(PQgetvalue(res, tupno, 6), NULL, 10);
li_provider = (int)strtol(PQgetvalue(res, tupno, 7), NULL, 10);
li_receiver = (int)strtol(PQgetvalue(res, tupno, 8), NULL, 10);
if (li_receiver == rtcfg_nodeid)
rtcfg_storeListen(li_origin, li_provider);
}
else if (strcmp(ev_type, "DROP_LISTEN") == 0)
{
/*
* DROP_LISTEN
*/
int li_origin;
int li_provider;
int li_receiver;
li_origin = (int)strtol(PQgetvalue(res, tupno, 6), NULL, 10);
li_provider = (int)strtol(PQgetvalue(res, tupno, 7), NULL, 10);
li_receiver = (int)strtol(PQgetvalue(res, tupno, 8), NULL, 10);
if (li_receiver == rtcfg_nodeid)
rtcfg_dropListen(li_origin, li_provider);
}
else if (strcmp(ev_type, "STORE_SET") == 0)
{
/*
* STORE_SET
*/
int set_id;
int set_origin;
char *set_comment;
set_id = (int)strtol(PQgetvalue(res, tupno, 6), NULL, 10);
set_origin = (int)strtol(PQgetvalue(res, tupno, 7), NULL, 10);
set_comment = PQgetvalue(res, tupno, 8);
rtcfg_storeSet(set_id, set_origin, set_comment);
}
else if (strcmp(ev_type, "DROP_SET") == 0)
{
/*
* DROP_SET
*/
int set_id;
set_id = (int)strtol(PQgetvalue(res, tupno, 6), NULL, 10);
rtcfg_dropSet(set_id);
}
else if (strcmp(ev_type, "MERGE_SET") == 0)
{
/*
* MERGE_SET
*/
int set_id;
int add_id;
set_id = (int)strtol(PQgetvalue(res, tupno, 6), NULL, 10);
add_id = (int)strtol(PQgetvalue(res, tupno, 7), NULL, 10);
rtcfg_dropSet(add_id);
}
else if (strcmp(ev_type, "SET_ADD_TABLE") == 0)
{
/*
* SET_ADD_TABLE
*/
/*
* Nothing to do ATM ... we don't support adding tables to
* subscribed sets and table information is not maintained in
* the runtime configuration.
*/
}
else if (strcmp(ev_type, "SET_ADD_SEQUENCE") == 0)
{
/*
* SET_ADD_SEQUENCE
*/
/*
* Nothing to do ATM ... we don't support adding sequences to
* subscribed sets and table information is not maintained in
* the runtime configuration.
*/
}
else if (strcmp(ev_type, "SET_DROP_TABLE") == 0)
{
/*
* SET_DROP_TABLE
*/
/*
* Nothing to do ATM ... table information is not maintained
* in the runtime configuration.
*/
}
else if (strcmp(ev_type, "SET_DROP_SEQUENCE") == 0)
{
/*
* SET_DROP_SEQUENCE
*/
/*
* Nothing to do ATM ... table information is not maintained
* in the runtime configuration.
*/
}
else if (strcmp(ev_type, "SET_MOVE_TABLE") == 0)
{
/*
* SET_MOVE_TABLE
*/
/*
* Nothing to do ATM ... table information is not maintained
* in the runtime configuration.
*/
}
else if (strcmp(ev_type, "SET_MOVE_SEQUENCE") == 0)
{
/*
* SET_MOVE_SEQUENCE
*/
/*
* Nothing to do ATM ... table information is not maintained
* in the runtime configuration.
*/
}
else if (strcmp(ev_type, "ADJUST_SEQ") == 0)
{
/*
* ADJUST_SEQ
*/
}
else if (strcmp(ev_type, "STORE_TRIGGER") == 0)
{
/*
* STORE_TRIGGER
*/
/*
* Nothing to do ATM
*/
}
else if (strcmp(ev_type, "DROP_TRIGGER") == 0)
{
/*
* DROP_TRIGGER
*/
/*
* Nothing to do ATM
*/
}
else if (strcmp(ev_type, "MOVE_SET") == 0)
{
/*
* MOVE_SET
*/
int set_id;
int old_origin;
int new_origin;
PGresult *res2;
SlonDString query2;
int sub_provider;
set_id = (int)strtol(PQgetvalue(res, tupno, 6), NULL, 10);
old_origin = (int)strtol(PQgetvalue(res, tupno, 7), NULL, 10);
new_origin = (int)strtol(PQgetvalue(res, tupno, 8), NULL, 10);
/*
* We have been the old origin of the set, so according to the
* rules we must have a provider now.
*/
dstring_init(&query2);
(void) slon_mkquery(&query2,
"select sub_provider from %s.sl_subscribe "
" where sub_receiver = %d and sub_set = %d",
rtcfg_namespace, rtcfg_nodeid, set_id);
res2 = PQexec(dbconn, dstring_data(&query2));
if (PQresultStatus(res2) != PGRES_TUPLES_OK)
{
slon_log(SLON_FATAL, "localListenThread: \"%s\" %s\n",
dstring_data(&query2),
PQresultErrorMessage(res2));
dstring_free(&query2);
PQclear(res2);
slon_retry();
}
if (PQntuples(res2) != 1)
{
slon_log(SLON_FATAL, "localListenThread: MOVE_SET "
"but no provider found for set %d\n",
set_id);
dstring_free(&query2);
PQclear(res2);
slon_retry();
}
sub_provider =
(int)strtol(PQgetvalue(res2, 0, 0), NULL, 10);
PQclear(res2);
dstring_free(&query2);
rtcfg_moveSet(set_id, old_origin, new_origin, sub_provider);
rtcfg_reloadListen(dbconn);
}
else if (strcmp(ev_type, "FAILOVER_SET") == 0)
{
/*
* FAILOVER_SET
*/
/*
* Nothing to do. The stored procedure will restart this
* daemon anyway.
*/
}
else if (strcmp(ev_type, "SUBSCRIBE_SET") == 0)
{
/*
* SUBSCRIBE_SET
*/
int sub_set;
int sub_provider;
int sub_receiver;
char *sub_forward;
sub_set = (int)strtol(PQgetvalue(res, tupno, 6), NULL, 10);
sub_provider = (int)strtol(PQgetvalue(res, tupno, 7), NULL, 10);
sub_receiver = (int)strtol(PQgetvalue(res, tupno, 8), NULL, 10);
sub_forward = PQgetvalue(res, tupno, 9);
if (sub_receiver == rtcfg_nodeid)
rtcfg_storeSubscribe(sub_set, sub_provider, sub_forward);
rtcfg_reloadListen(dbconn);
}
else if (strcmp(ev_type, "ENABLE_SUBSCRIPTION") == 0)
{
/*
* ENABLE_SUBSCRIPTION
*/
int sub_set;
int sub_provider;
int sub_receiver;
char *sub_forward;
sub_set = (int)strtol(PQgetvalue(res, tupno, 6), NULL, 10);
sub_provider = (int)strtol(PQgetvalue(res, tupno, 7), NULL, 10);
sub_receiver = (int)strtol(PQgetvalue(res, tupno, 8), NULL, 10);
sub_forward = PQgetvalue(res, tupno, 9);
if (sub_receiver == rtcfg_nodeid)
rtcfg_enableSubscription(sub_set, sub_provider, sub_forward);
rtcfg_reloadListen(dbconn);
}
else if (strcmp(ev_type, "UNSUBSCRIBE_SET") == 0)
{
/*
* UNSUBSCRIBE_SET
*/
int sub_set;
int sub_receiver;
sub_set = (int)strtol(PQgetvalue(res, tupno, 6), NULL, 10);
sub_receiver = (int)strtol(PQgetvalue(res, tupno, 7), NULL, 10);
if (sub_receiver == rtcfg_nodeid)
rtcfg_unsubscribeSet(sub_set);
rtcfg_reloadListen(dbconn);
}
else if (strcmp(ev_type, "DDL_SCRIPT") == 0)
{
/*
* DDL_SCRIPT
*/
/*
* Nothing to do ATM
*/
}
else if (strcmp(ev_type, "ACCEPT_SET") == 0)
{
/*
* ACCEPT_SET
*/
/*
* Nothing to do locally
*/
slon_log(SLON_DEBUG1, "localListenThread: ACCEPT_SET\n");
rtcfg_reloadListen(dbconn);
}
else
{
slon_log(SLON_FATAL,
"localListenThread: event %s: Unknown event type: %s\n",
rtcfg_lastevent, ev_type);
slon_abort();
}
}
PQclear(res);
/*
* If there were events, commit the transaction.
*/
if (ntuples > 0)
{
poll_sleep = 0; /* drop polling time back to 0... */
res = PQexec(dbconn, "commit transaction");
if (PQresultStatus(res) != PGRES_COMMAND_OK)
{
slon_log(SLON_FATAL,
"localListenThread: \"%s\" - %s\n",
dstring_data(&query1), PQresultErrorMessage(res));
PQclear(res);
dstring_free(&query1);
slon_retry();
break;
}
PQclear(res);
}
else
{
/*
* No database events received. Rollback instead.
*/
/* Increase the amount of time to sleep, to a max of sync_interval_timeout */
poll_sleep += sync_interval;
if (poll_sleep > sync_interval_timeout) {
poll_sleep = sync_interval_timeout;
}
res = PQexec(dbconn, "rollback transaction;");
if (PQresultStatus(res) != PGRES_COMMAND_OK)
{
slon_log(SLON_FATAL,
"localListenThread: \"rollback transaction;\" - %s\n",
PQresultErrorMessage(res));
PQclear(res);
slon_retry();
break;
}
PQclear(res);
}
/*
* Wait for notify or for timeout
*/
if (sched_wait_time(conn, SCHED_WAIT_SOCK_READ, poll_sleep) != SCHED_STATUS_OK)
break;
}
/*
* The scheduler asked us to shutdown. Free memory and close the DB
* connection.
*/
dstring_free(&query1);
slon_disconnectdb(conn);
#ifdef SLON_MEMDEBUG
conn = NULL;
#endif
slon_log(SLON_INFO, "localListenThread: thread done\n");
pthread_exit(NULL);
}
/* ----------
* remoteListen_adjust_listat
*
* local function to (re)adjust the known nodes to the global configuration.
* ----------
*/
static void
remoteListen_adjust_listat(SlonNode * node, struct listat ** listat_head,
struct listat ** listat_tail)
{
SlonNode *lnode;
SlonListen *listen;
struct listat *listat;
struct listat *linext;
int found;
/*
* Remove listat entries for event origins that this remote node stopped
* providing for us, or where the origin got disabled.
*/
for (listat = *listat_head; listat;)
{
linext = listat->next;
found = false;
for (listen = node->listen_head; listen; listen = listen->next)
{
/*
* Check if the sl_listen entry still exists and that the
* li_origin is active.
*/
if (listen->li_origin == listat->li_origin)
{
lnode = rtcfg_findNode(listat->li_origin);
if (lnode != NULL && lnode->no_active)
found = (int) true;
break;
}
}
/*
* Remove obsolete item
*/
if (!found)
{
slon_log(SLON_DEBUG2,
"remoteListenThread_%d: stop listening for "
"event origin %d\n",
node->no_id, listat->li_origin);
DLLIST_REMOVE(*listat_head, *listat_tail, listat);
free(listat);
}
listat = linext;
}
/*
* Now add new or newly enabled sl_listen entries to it.
*/
for (listen = node->listen_head; listen; listen = listen->next)
{
/*
* skip inactive or unknown nodes
*/
lnode = rtcfg_findNode(listen->li_origin);
if (lnode == NULL || !(lnode->no_active))
continue;
/*
* check if we have that entry
*/
found = false;
for (listat = *listat_head; listat; listat = listat->next)
{
if (listen->li_origin == listat->li_origin)
{
found = true;
break;
}
}
/*
* Add missing entries
*/
if (!found)
{
slon_log(SLON_DEBUG2,
"remoteListenThread_%d: start listening for "
"event origin %d\n",
node->no_id, listen->li_origin);
listat = (struct listat *) malloc(sizeof(struct listat));
if (listat == NULL)
{
perror("remoteListen_adjust_listat: malloc()");
slon_restart();
}
memset(listat, 0, sizeof(struct listat));
listat->li_origin = listen->li_origin;
DLLIST_ADD_TAIL(*listat_head, *listat_tail, listat);
}
}
}
