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/*-
* See the file LICENSE for redistribution information.
*
* Copyright (c) 2001-2009 Oracle. All rights reserved.
*
* $Id$
*/
#include <sys/types.h>
#include <signal.h>
#include <stdlib.h>
#include <string.h>
#ifndef _WIN32
#include <unistd.h>
#endif
#include <db.h>
#include "../common/rep_common.h"
typedef struct {
SHARED_DATA shared_data;
} APP_DATA;
const char *progname = "ex_rep_mgr";
static void event_callback __P((DB_ENV *, u_int32_t, void *));
int
main(argc, argv)
int argc;
char *argv[];
{
DB_ENV *dbenv;
SETUP_DATA setup_info;
repsite_t *site_list;
APP_DATA my_app_data;
thread_t ckp_thr, lga_thr;
supthr_args sup_args;
u_int32_t start_policy;
int i, ret, t_ret;
memset(&setup_info, 0, sizeof(SETUP_DATA));
setup_info.progname = progname;
memset(&my_app_data, 0, sizeof(APP_DATA));
dbenv = NULL;
ret = 0;
start_policy = DB_REP_ELECTION;
if ((ret = create_env(progname, &dbenv)) != 0)
goto err;
dbenv->app_private = &my_app_data;
(void)dbenv->set_event_notify(dbenv, event_callback);
/* Parse command line and perform common replication setup. */
if ((ret = common_rep_setup(dbenv, argc, argv, &setup_info)) != 0)
goto err;
/* Perform repmgr-specific setup based on command line options. */
if (setup_info.role == MASTER)
start_policy = DB_REP_MASTER;
else if (setup_info.role == CLIENT)
start_policy = DB_REP_CLIENT;
if ((ret = dbenv->repmgr_set_local_site(dbenv, setup_info.self.host,
setup_info.self.port, 0)) != 0) {
fprintf(stderr, "Could not set listen address (%d).\n", ret);
goto err;
}
site_list = setup_info.site_list;
for (i = 0; i < setup_info.remotesites; i++) {
if ((ret = dbenv->repmgr_add_remote_site(dbenv,
site_list[i].host, site_list[i].port, NULL,
site_list[i].peer ? DB_REPMGR_PEER : 0)) != 0) {
dbenv->err(dbenv, ret,
"Could not add site %s:%d", site_list[i].host,
(int)site_list[i].port);
goto err;
}
}
/*
* Configure heartbeat timeouts so that repmgr monitors the
* health of the TCP connection. Master sites broadcast a heartbeat
* at the frequency specified by the DB_REP_HEARTBEAT_SEND timeout.
* Client sites wait for message activity the length of the
* DB_REP_HEARTBEAT_MONITOR timeout before concluding that the
* connection to the master is lost. The DB_REP_HEARTBEAT_MONITOR
* timeout should be longer than the DB_REP_HEARTBEAT_SEND timeout.
*/
if ((ret = dbenv->rep_set_timeout(dbenv, DB_REP_HEARTBEAT_SEND,
5000000)) != 0)
dbenv->err(dbenv, ret,
"Could not set heartbeat send timeout.\n");
if ((ret = dbenv->rep_set_timeout(dbenv, DB_REP_HEARTBEAT_MONITOR,
10000000)) != 0)
dbenv->err(dbenv, ret,
"Could not set heartbeat monitor timeout.\n");
/*
* The following repmgr features may also be useful to your
* application. See Berkeley DB documentation for more details.
* - Two-site strict majority rule - In a two-site replication
* group, require both sites to be available to elect a new
* master.
* - Timeouts - Customize the amount of time repmgr waits
* for such things as waiting for acknowledgements or attempting
* to reconnect to other sites.
* - Site list - return a list of sites currently known to repmgr.
*/
if ((ret = env_init(dbenv, setup_info.home)) != 0)
goto err;
/* Start checkpoint and log archive threads. */
sup_args.dbenv = dbenv;
sup_args.shared = &my_app_data.shared_data;
if ((ret = start_support_threads(dbenv, &sup_args, &ckp_thr,
&lga_thr)) != 0)
goto err;
if ((ret = dbenv->repmgr_start(dbenv, 3, start_policy)) != 0)
goto err;
if ((ret = doloop(dbenv, &my_app_data.shared_data)) != 0) {
dbenv->err(dbenv, ret, "Client failed");
goto err;
}
/* Finish checkpoint and log archive threads. */
if ((ret = finish_support_threads(&ckp_thr, &lga_thr)) != 0)
goto err;
/*
* We have used the DB_TXN_NOSYNC environment flag for improved
* performance without the usual sacrifice of transactional durability,
* as discussed in the "Transactional guarantees" page of the Reference
* Guide: if one replication site crashes, we can expect the data to
* exist at another site. However, in case we shut down all sites
* gracefully, we push out the end of the log here so that the most
* recent transactions don't mysteriously disappear.
*/
if ((ret = dbenv->log_flush(dbenv, NULL)) != 0) {
dbenv->err(dbenv, ret, "log_flush");
goto err;
}
err:
if (dbenv != NULL &&
(t_ret = dbenv->close(dbenv, 0)) != 0) {
fprintf(stderr, "failure closing env: %s (%d)\n",
db_strerror(t_ret), t_ret);
if (ret == 0)
ret = t_ret;
}
return (ret);
}
static void
event_callback(dbenv, which, info)
DB_ENV *dbenv;
u_int32_t which;
void *info;
{
APP_DATA *app = dbenv->app_private;
SHARED_DATA *shared = &app->shared_data;
info = NULL; /* Currently unused. */
switch (which) {
case DB_EVENT_REP_CLIENT:
shared->is_master = 0;
shared->in_client_sync = 1;
break;
case DB_EVENT_REP_MASTER:
shared->is_master = 1;
shared->in_client_sync = 0;
break;
case DB_EVENT_REP_NEWMASTER:
shared->in_client_sync = 1;
break;
case DB_EVENT_REP_PERM_FAILED:
/*
* Did not get enough acks to guarantee transaction
* durability based on the configured ack policy. This
* transaction will be flushed to the master site's
* local disk storage for durability.
*/
printf(
"Insufficient acknowledgements to guarantee transaction durability.\n");
break;
case DB_EVENT_REP_STARTUPDONE:
shared->in_client_sync = 0;
break;
default:
dbenv->errx(dbenv, "ignoring event %d", which);
}
}
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