- introduce stat_backend, an API for pluggable statistic backends

  > statistics are no longer static structures in shared memory
  > statistics are only set, smtpd never uses them in its logic
  > each statistic is a key/value where key can be any (dynamic) string
- convert all uses of the former API to use the new one
- implement stat_ramstat that keeps non-persistent stats in ram structure

ok eric@, ok chl@

16 files changed, 472 insertions, 349 deletions

diff --git a/usr.sbin/smtpd/control.c b/usr.sbin/smtpd/control.c
index ce9356e18f6..969a437e7cb 100644
--- a/usr.sbin/smtpd/control.c
+++ b/usr.sbin/smtpd/control.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: control.c,v 1.67 2012/08/10 09:16:02 eric Exp $	*/
+/*	$OpenBSD: control.c,v 1.68 2012/08/18 18:18:23 gilles Exp $	*/
 
 /*
  * Copyright (c) 2008 Pierre-Yves Ritschard <pyr@openbsd.org>
@@ -61,10 +61,17 @@ void		 control_dispatch_ext(int, short, void *);
 
 struct ctl_connlist	ctl_conns;
 
+static struct stat_backend *stat_backend = NULL;
+extern const char *backend_stat;
+
+static size_t sessions;
+
 void
 control_imsg(struct imsgev *iev, struct imsg *imsg)
 {
 	struct ctl_conn	*c;
+	char		*key;
+	struct stat_kv	*stat_kv;
 
 	log_imsg(PROC_CONTROL, iev->proc, imsg);
 
@@ -80,6 +87,24 @@ control_imsg(struct imsgev *iev, struct imsg *imsg)
 		}
 	}
 
+	switch (imsg->hdr.type) {
+	case IMSG_STAT_INCREMENT:
+		key = imsg->data;
+		if (stat_backend)
+			stat_backend->increment(key);
+		return;
+	case IMSG_STAT_DECREMENT:
+		key = imsg->data;
+		if (stat_backend)
+			stat_backend->decrement(key);
+		return;
+	case IMSG_STAT_SET:
+		stat_kv = (struct stat_kv *)imsg->data;
+		if (stat_backend)
+			stat_backend->set(stat_kv->key, stat_kv->val);
+		return;
+	}
+
 	errx(1, "control_imsg: unexpected %s imsg",
 	    imsg_to_str(imsg->hdr.type));
 }
@@ -109,11 +134,12 @@ control(void)
 	struct event		 ev_sigint;
 	struct event		 ev_sigterm;
 	struct peer		 peers [] = {
-		{ PROC_SCHEDULER,	 imsg_dispatch },
-		{ PROC_QUEUE,	 imsg_dispatch },
-		{ PROC_SMTP,	 imsg_dispatch },
-		{ PROC_MFA,	 imsg_dispatch },
-		{ PROC_PARENT,	 imsg_dispatch },
+		{ PROC_SCHEDULER,	imsg_dispatch },
+		{ PROC_QUEUE,		imsg_dispatch },
+		{ PROC_SMTP,		imsg_dispatch },
+		{ PROC_MFA,		imsg_dispatch },
+		{ PROC_PARENT,		imsg_dispatch },
+		{ PROC_LKA,		imsg_dispatch }
 	};
 
 	switch (pid = fork()) {
@@ -160,6 +186,9 @@ control(void)
 	session_socket_blockmode(fd, BM_NONBLOCK);
 	control_state.fd = fd;
 
+	stat_backend = env->sc_stat;
+	stat_backend->init();
+
 	if (chroot(pw->pw_dir) == -1)
 		fatal("control: chroot");
 	if (chdir("/") == -1)
@@ -255,7 +284,9 @@ control_accept(int listenfd, short event, void *arg)
 	event_add(&c->iev.ev, NULL);
 	TAILQ_INSERT_TAIL(&ctl_conns, c, entry);
 
-	if (stat_increment(STATS_CONTROL_SESSION) >= env->sc_maxconn) {
+	stat_backend->increment("control.session");
+
+	if (++sessions >= env->sc_maxconn) {
 		log_warnx("ctl client limit hit, disabling new connections");
 		event_del(&control_state.ev);
 	}
@@ -288,7 +319,9 @@ control_close(int fd)
 	close(fd);
 	free(c);
 
-	if (stat_decrement(STATS_CONTROL_SESSION) < env->sc_maxconn &&
+	stat_backend->decrement("control.session");
+
+	if (--sessions < env->sc_maxconn &&
 	    !event_pending(&control_state.ev, EV_READ, NULL)) {
 		log_warnx("re-enabling ctl connections");
 		event_add(&control_state.ev, NULL);
@@ -305,6 +338,10 @@ control_dispatch_ext(int fd, short event, void *arg)
 	uid_t			 euid;
 	gid_t			 egid;
 	uint64_t		 id;
+	struct stat_kv		*kvp;
+	char			*key;
+	size_t			 val;
+
 
 	if (getpeereid(fd, &euid, &egid) == -1)
 		fatal("getpeereid");
@@ -352,8 +389,21 @@ control_dispatch_ext(int fd, short event, void *arg)
 		case IMSG_STATS:
 			if (euid)
 				goto badcred;
-			imsg_compose_event(&c->iev, IMSG_STATS, 0, 0, -1,
-			    env->stats, sizeof(struct stats));
+			imsg_compose_event(&c->iev, IMSG_STATS, 0, 0, -1, NULL, 0);
+			break;
+
+		case IMSG_STATS_GET:
+			if (euid)
+				goto badcred;
+			kvp = imsg.data;
+			if (! stat_backend->iter(&kvp->iter, &key, &val))
+				kvp->iter = NULL;
+			else {
+				strlcpy(kvp->key, key, sizeof kvp->key);
+				kvp->val = val;
+			}
+			imsg_compose_event(&c->iev, IMSG_STATS_GET, 0, 0, -1,
+			    kvp, sizeof *kvp);
 			break;
 
 		case IMSG_CTL_SHUTDOWN:
diff --git a/usr.sbin/smtpd/dns.c b/usr.sbin/smtpd/dns.c
index d502ef9396b..03746eb0987 100644
--- a/usr.sbin/smtpd/dns.c
+++ b/usr.sbin/smtpd/dns.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: dns.c,v 1.51 2012/08/08 17:31:55 eric Exp $	*/
+/*	$OpenBSD: dns.c,v 1.52 2012/08/18 18:18:23 gilles Exp $	*/
 
 /*
  * Copyright (c) 2008 Gilles Chehade <gilles@openbsd.org>
@@ -145,14 +145,14 @@ dns_async(struct imsgev *asker, int type, struct dns *query)
 			return;
 		}
 		dnssession_mx_insert(s, query->host, 0);
-		stat_increment(STATS_LKA_SESSION_HOST);
+		stat_increment("lka.session.host");
 		dns_asr_dispatch_host(s);
 		return;
 	case IMSG_DNS_PTR:
 		s->as = getnameinfo_async((struct sockaddr*)&query->ss,
 		    query->ss.ss_len,
 		    s->query.host, sizeof(s->query.host), NULL, 0, 0, NULL);
-		stat_increment(STATS_LKA_SESSION_CNAME);
+		stat_increment("lka.session.cname");
 		if (s->as == NULL) {
 			log_debug("dns_async: asr_query_cname error");
 			break;
@@ -162,7 +162,7 @@ dns_async(struct imsgev *asker, int type, struct dns *query)
 	case IMSG_DNS_MX:
 		log_debug("dns: lookup mx \"%s\"", query->host);
 		s->as = res_query_async(query->host, C_IN, T_MX, NULL, 0, NULL);
-		stat_increment(STATS_LKA_SESSION_MX);
+		stat_increment("lka.session.mx");
 		if (s->as == NULL) {
 			log_debug("dns_async: asr_query_dns error");
 			break;
@@ -174,7 +174,7 @@ dns_async(struct imsgev *asker, int type, struct dns *query)
 		break;
 	}
 
-	stat_increment(STATS_LKA_FAILURE);
+	stat_increment("lka.failure");
 	dnssession_destroy(s);
 }
 
@@ -223,7 +223,7 @@ dns_asr_error(int ar_err)
 		return DNS_OK;
 	case NO_DATA:
 	case NO_RECOVERY:
-		stat_increment(STATS_LKA_FAILURE);
+		stat_increment("lka.failure");
 		return DNS_EINVAL;
 	default:
 		return DNS_RETRY;
@@ -354,7 +354,7 @@ dnssession_init(struct dns *query)
 	if (s == NULL)
 		fatal("dnssession_init: calloc");
 
-	stat_increment(STATS_LKA_SESSION);
+	stat_increment("lka.session");
 
 	s->id = query->id;
 	s->query = *query;
@@ -365,7 +365,7 @@ dnssession_init(struct dns *query)
 static void
 dnssession_destroy(struct dnssession *s)
 {
-	stat_decrement(STATS_LKA_SESSION);
+	stat_decrement("lka.session");
 	SPLAY_REMOVE(dnstree, &dns_sessions, s);
 	event_del(&s->ev);
 	free(s);
diff --git a/usr.sbin/smtpd/lka.c b/usr.sbin/smtpd/lka.c
index 169662dd521..1e1bae88ee9 100644
--- a/usr.sbin/smtpd/lka.c
+++ b/usr.sbin/smtpd/lka.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: lka.c,v 1.133 2012/05/12 15:31:43 gilles Exp $	*/
+/*	$OpenBSD: lka.c,v 1.134 2012/08/18 18:18:23 gilles Exp $	*/
 
 /*
  * Copyright (c) 2008 Pierre-Yves Ritschard <pyr@openbsd.org>
@@ -256,7 +256,8 @@ lka(void)
 		{ PROC_MFA,	imsg_dispatch },
 		{ PROC_QUEUE,	imsg_dispatch },
 		{ PROC_SMTP,	imsg_dispatch },
-		{ PROC_MTA,	imsg_dispatch }
+		{ PROC_MTA,	imsg_dispatch },
+		{ PROC_CONTROL,	imsg_dispatch }
 	};
 
 	switch (pid = fork()) {
diff --git a/usr.sbin/smtpd/queue.c b/usr.sbin/smtpd/queue.c
index f7e4586057f..ece47ff5bc2 100644
--- a/usr.sbin/smtpd/queue.c
+++ b/usr.sbin/smtpd/queue.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: queue.c,v 1.125 2012/08/11 19:18:36 chl Exp $	*/
+/*	$OpenBSD: queue.c,v 1.126 2012/08/18 18:18:23 gilles Exp $	*/
 
 /*
  * Copyright (c) 2008 Gilles Chehade <gilles@openbsd.org>
@@ -85,7 +85,7 @@ queue_imsg(struct imsgev *iev, struct imsg *imsg)
 			msgid = evpid_to_msgid(e->id);
 			if (queue_message_commit(msgid)) {
 				stat_increment(e->flags & DF_ENQUEUED ?
-				    STATS_QUEUE_LOCAL : STATS_QUEUE_REMOTE);
+				    "queue.local" : "queue.remote");
 				imsg_compose_event(env->sc_ievs[PROC_SCHEDULER],
 				    IMSG_QUEUE_COMMIT_MESSAGE, 0, 0, -1,
 				    &msgid, sizeof msgid);
diff --git a/usr.sbin/smtpd/scheduler.c b/usr.sbin/smtpd/scheduler.c
index b71249b4956..bf7ddf9d24d 100644
--- a/usr.sbin/smtpd/scheduler.c
+++ b/usr.sbin/smtpd/scheduler.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: scheduler.c,v 1.11 2012/08/09 19:16:26 eric Exp $	*/
+/*	$OpenBSD: scheduler.c,v 1.12 2012/08/18 18:18:23 gilles Exp $	*/
 
 /*
  * Copyright (c) 2008 Gilles Chehade <gilles@openbsd.org>
@@ -408,6 +408,4 @@ scheduler_process_mta(struct scheduler_batch *batch)
 
 	imsg_compose_event(env->sc_ievs[PROC_QUEUE], IMSG_BATCH_CLOSE,
 	    0, 0, -1, NULL, 0);
-
-	stat_increment(STATS_MTA_SESSION);
 }
diff --git a/usr.sbin/smtpd/scheduler_ramqueue.c b/usr.sbin/smtpd/scheduler_ramqueue.c
index 1630d6e5cb2..44cbd31cf2c 100644
--- a/usr.sbin/smtpd/scheduler_ramqueue.c
+++ b/usr.sbin/smtpd/scheduler_ramqueue.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: scheduler_ramqueue.c,v 1.13 2012/08/11 19:19:19 chl Exp $	*/
+/*	$OpenBSD: scheduler_ramqueue.c,v 1.14 2012/08/18 18:18:23 gilles Exp $	*/
 
 /*
  * Copyright (c) 2012 Gilles Chehade <gilles@openbsd.org>
@@ -160,8 +160,10 @@ scheduler_ramqueue_insert(struct scheduler_info *si)
 	}
 
 	/* find/prepare the host in ramqueue update */
-	if ((host = rq_host_lookup(&update->hosts, si->destination)) == NULL)
+	if ((host = rq_host_lookup(&update->hosts, si->destination)) == NULL) {
 		host = rq_host_create(&update->hosts, si->destination);
+		stat_increment("scheduler.ramqueue.host");
+	}
 
 	/* find/prepare the hosttree message in ramqueue update */
 	if ((batch = tree_get(&host->batches, msgid)) == NULL) {
@@ -169,6 +171,7 @@ scheduler_ramqueue_insert(struct scheduler_info *si)
 		batch->msgid = msgid;
 		tree_init(&batch->envelopes);
 		tree_xset(&host->batches, msgid, batch);
+		stat_increment("scheduler.ramqueue.batch");
 	}
 
 	/* find/prepare the msgtree message in ramqueue update */
@@ -177,6 +180,7 @@ scheduler_ramqueue_insert(struct scheduler_info *si)
 		message->msgid = msgid;
 		tree_init(&message->envelopes);
 		tree_xset(&update->messages, msgid, message);
+		stat_increment("scheduler.ramqueue.message");
 	}
 
 	/* create envelope in ramqueue message */
@@ -188,6 +192,8 @@ scheduler_ramqueue_insert(struct scheduler_info *si)
 	envelope->sched = scheduler_compute_schedule(si);
 	envelope->expire = si->creation + si->expire;
 
+	stat_increment("scheduler.ramqueue.envelope");
+
 	if (envelope->expire < envelope->sched) {
 		envelope->flags |= RQ_ENVELOPE_EXPIRED;
 		tree_xset(&update->expired, envelope->evpid, envelope);
@@ -619,6 +625,7 @@ rq_envelope_delete(struct rq_queue *rq, struct rq_envelope *envelope)
 	if (tree_empty(&message->envelopes)) {
 		tree_xpop(&rq->messages, msgid);
 		free(message);
+		stat_decrement("scheduler.ramqueue.message");
 	}
 
 	tree_xpop(&batch->envelopes, envelope->evpid);
@@ -627,10 +634,14 @@ rq_envelope_delete(struct rq_queue *rq, struct rq_envelope *envelope)
 		if (tree_empty(&host->batches)) {
 			SPLAY_REMOVE(hosttree, &rq->hosts, host);
 			free(host);
+			stat_decrement("scheduler.ramqueue.host");
 		}
 		free(batch);
+		stat_decrement("scheduler.ramqueue.batch");
 	}
 	free(envelope);
+
+	stat_decrement("scheduler.ramqueue.envelope");
 }
 
 static const char *
diff --git a/usr.sbin/smtpd/smtp.c b/usr.sbin/smtpd/smtp.c
index a9b217df20e..c4d7ab3aa58 100644
--- a/usr.sbin/smtpd/smtp.c
+++ b/usr.sbin/smtpd/smtp.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: smtp.c,v 1.103 2012/08/09 09:48:02 eric Exp $	*/
+/*	$OpenBSD: smtp.c,v 1.104 2012/08/18 18:18:23 gilles Exp $	*/
 
 /*
  * Copyright (c) 2008 Gilles Chehade <gilles@openbsd.org>
@@ -49,6 +49,7 @@ static void smtp_accept(int, short, void *);
 static struct session *smtp_new(struct listener *);
 static struct session *session_lookup(u_int64_t);
 
+static size_t sessions;
 
 static void
 smtp_imsg(struct imsgev *iev, struct imsg *imsg)
@@ -516,15 +517,17 @@ smtp_new(struct listener *l)
 	strlcpy(s->s_msg.tag, l->tag, sizeof(s->s_msg.tag));
 	SPLAY_INSERT(sessiontree, &env->sc_sessions, s);
 
-	if (stat_increment(STATS_SMTP_SESSION) >= env->sc_maxconn) {
+	stat_increment("smtp.session");
+
+	if (++sessions >= env->sc_maxconn) {
 		log_warnx("client limit hit, disabling incoming connections");
 		smtp_pause();
 	}
 
 	if (s->s_l->ss.ss_family == AF_INET)
-		stat_increment(STATS_SMTP_SESSION_INET4);
+		stat_increment("smtp.session.inet4");
 	if (s->s_l->ss.ss_family == AF_INET6)
-		stat_increment(STATS_SMTP_SESSION_INET6);
+		stat_increment("smtp.session.inet6");
 
 	iobuf_init(&s->s_iobuf, MAX_LINE_SIZE, MAX_LINE_SIZE);
 	io_init(&s->s_io, -1, s, session_io, &s->s_iobuf);
@@ -533,6 +536,20 @@ smtp_new(struct listener *l)
 	return (s);
 }
 
+void
+smtp_destroy(struct session *session)
+{
+	size_t	resume;
+
+	resume = env->sc_maxconn * 95 / 100;
+
+	if (--sessions == resume) {
+		log_warnx("re-enabling incoming connections");
+		smtp_resume();
+	}
+}
+
+
 /*
  * Helper function for handling IMSG replies.
  */
diff --git a/usr.sbin/smtpd/smtp_session.c b/usr.sbin/smtpd/smtp_session.c
index 396f3ef3fb1..d173fef7599 100644
--- a/usr.sbin/smtpd/smtp_session.c
+++ b/usr.sbin/smtpd/smtp_session.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: smtp_session.c,v 1.164 2012/08/18 16:05:54 chl Exp $	*/
+/*	$OpenBSD: smtp_session.c,v 1.165 2012/08/18 18:18:23 gilles Exp $	*/
 
 /*
  * Copyright (c) 2008 Gilles Chehade <gilles@openbsd.org>
@@ -610,9 +610,9 @@ session_io(struct io *io, int evt)
 	case IO_TLSREADY:
 		s->s_flags |= F_SECURE;
 		if (s->s_l->flags & F_SMTPS)
-			stat_increment(STATS_SMTP_SMTPS);
+			stat_increment("smtp.smtps");
 		if (s->s_l->flags & F_STARTTLS)
-			stat_increment(STATS_SMTP_STARTTLS);
+			stat_increment("smtp.tls");
 		if (s->s_state == S_INIT) {
 			io_set_write(&s->s_io);
 			session_respond(s, SMTPD_BANNER, env->sc_hostname);
@@ -694,7 +694,7 @@ session_pickup(struct session *s, struct submit_status *ss)
 
 	if ((ss != NULL && ss->code == 421) ||
 	    (s->s_dstatus & DS_TEMPFAILURE)) {
-		env->stats->smtp.tempfail++;
+		stat_increment("smtp.tempfail");
 		session_respond(s, "421 Service temporarily unavailable");
 		session_enter_state(s, S_QUIT);
 		io_reload(&s->s_io);
@@ -924,7 +924,7 @@ session_line(struct session *s, char *line, size_t len)
 
 tempfail:
 	session_respond(s, "421 4.0.0 Service temporarily unavailable");
-	env->stats->smtp.tempfail++;
+	stat_increment("smtp.tempfail");
 	session_enter_state(s, S_QUIT);
 }
 
@@ -947,7 +947,7 @@ session_read_data(struct session *s, char *line)
 		} else if (s->s_dstatus & DS_TEMPFAILURE) {
 			session_respond(s, "421 4.0.0 Temporary failure");
 			session_enter_state(s, S_QUIT);
-			env->stats->smtp.tempfail++;
+			stat_increment("smtp.tempfail");
 		} else {
 			session_imsg(s, PROC_QUEUE, IMSG_QUEUE_COMMIT_MESSAGE,
 			    0, 0, -1, &s->s_msg, sizeof(s->s_msg));
@@ -991,8 +991,6 @@ session_read_data(struct session *s, char *line)
 void
 session_destroy(struct session *s, const char * reason)
 {
-	size_t	resume;
-
 	log_debug("smtp: %p: deleting session: %s", s, reason);
 
 	if (s->s_flags & F_ZOMBIE)
@@ -1009,10 +1007,10 @@ session_destroy(struct session *s, const char * reason)
 	if (s->s_ssl) {
 		if (s->s_l->flags & F_SMTPS)
 			if (s->s_flags & F_SECURE)
-				stat_decrement(STATS_SMTP_SMTPS);
+				stat_decrement("smtp.smtps");
 		if (s->s_l->flags & F_STARTTLS)
 			if (s->s_flags & F_SECURE)
-				stat_decrement(STATS_SMTP_STARTTLS);
+				stat_decrement("smtp.tls");
 	}
 
 	event_del(&s->s_ev); /* in case something was scheduled */
@@ -1020,11 +1018,7 @@ session_destroy(struct session *s, const char * reason)
 	iobuf_clear(&s->s_iobuf);
 
 	/* resume when session count decreases to 95% */
-	resume = env->sc_maxconn * 95 / 100;
-	if (stat_decrement(STATS_SMTP_SESSION) == resume) {
-		log_warnx("re-enabling incoming connections");
-		smtp_resume();
-	}
+	stat_decrement("smtp.session");
 
 	/* If the session is waiting for an imsg, do not kill it now, since
 	 * the id must still be valid.
@@ -1035,6 +1029,9 @@ session_destroy(struct session *s, const char * reason)
 	}
 
     finalize:
+
+	smtp_destroy(s);
+
 	SPLAY_REMOVE(sessiontree, &env->sc_sessions, s);
 	bzero(s, sizeof(*s));
 	free(s);
@@ -1130,7 +1127,7 @@ session_respond(struct session *s, char *fmt, ...)
 		struct timeval tv = { delay, 0 };
 
 		io_pause(&s->s_io, IO_PAUSE_OUT);
-		env->stats->smtp.delays++;
+		stat_increment("smtp.delays");
 
 		/* in case session_respond is called multiple times */
 		evtimer_del(&s->s_ev);
diff --git a/usr.sbin/smtpd/smtpctl.c b/usr.sbin/smtpd/smtpctl.c
index af948be20fa..e8fb5e80f78 100644
--- a/usr.sbin/smtpd/smtpctl.c
+++ b/usr.sbin/smtpd/smtpctl.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: smtpctl.c,v 1.85 2012/08/08 17:33:55 eric Exp $	*/
+/*	$OpenBSD: smtpctl.c,v 1.86 2012/08/18 18:18:23 gilles Exp $	*/
 
 /*
  * Copyright (c) 2006 Pierre-Yves Ritschard <pyr@openbsd.org>
@@ -45,7 +45,7 @@
 void usage(void);
 static void setup_env(struct smtpd *);
 static int show_command_output(struct imsg *);
-static int show_stats_output(struct imsg *);
+static void show_stats_output(void);
 static void show_queue(int);
 static void show_envelope(struct envelope *, int);
 static void getflag(u_int *, int, char *, char *, size_t);
@@ -262,7 +262,8 @@ connected:
 				done = show_command_output(&imsg);
 				break;
 			case SHOW_STATS:
-				done = show_stats_output(&imsg);
+				show_stats_output();
+				done = 1;
 				break;
 			case NONE:
 				break;
@@ -299,141 +300,55 @@ show_command_output(struct imsg *imsg)
 }
 
 static void
-stat_print(int stat, int what)
+show_stats_output(void)
 {
-	static const char *names[STATS_MAX] = {
-		"smtp.sessions",
-		"smtp.sessions.inet4",
-		"smtp.sessions.inet6",
-		"smtp.sessions.smtps",
-		"smtp.sessions.starttls",
-
-		"mta.sessions",
-
-		"mda.sessions",
-
-		"control.sessions",
-
-		"lka.sessions",
-		"lka.sessions.mx",
-		"lka.sessions.host",
-		"lka.sessions.cname",
-		"lka.sessions.failure",
-
-		"scheduler",
-		"scheduler.bounces",
-
-		"queue.inserts.local",
-		"queue.inserts.remote",
-
-		"ramqueue.envelopes",
-		"ramqueue.messages",
-		"ramqueue.batches",
-		"ramqueue.hosts",
-	};
-	const char *sfx;
-
-	if (what == STAT_ACTIVE)
-		sfx = ".active";
-	else if (what == STAT_MAXACTIVE)
-		sfx = ".maxactive";
-	else
-		sfx = "";
+	struct stat_kv	kv, *kvp;
+	struct imsg	imsg;
+	int n;
 
-	printf("%s%s=%zd\n", names[stat], sfx, stat_get(stat, what));
-}
 
-static int
-show_stats_output(struct imsg *imsg)
-{
-	struct stats	*stats;
+	bzero(&kv, sizeof kv);
 
-	if (imsg->hdr.type != IMSG_STATS)
-		errx(1, "show_stats_output: bad hdr type (%d)", imsg->hdr.type);
+again:
+	imsg_compose(ibuf, IMSG_STATS_GET, 0, 0, -1, &kv, sizeof kv);
 	
-	if (imsg->hdr.len - IMSG_HEADER_SIZE != sizeof(*stats))
-		errx(1, "show_stats_output: bad data size");
-
-	stats = imsg->data;
-	stat_init(stats->counters, STATS_MAX);
-
-	stat_print(STATS_CONTROL_SESSION, STAT_COUNT);
-	stat_print(STATS_CONTROL_SESSION, STAT_ACTIVE);
-	stat_print(STATS_CONTROL_SESSION, STAT_MAXACTIVE);
-
-	stat_print(STATS_MDA_SESSION, STAT_COUNT);
-	stat_print(STATS_MDA_SESSION, STAT_ACTIVE);
-	stat_print(STATS_MDA_SESSION, STAT_MAXACTIVE);
-
-	stat_print(STATS_MTA_SESSION, STAT_COUNT);
-	stat_print(STATS_MTA_SESSION, STAT_ACTIVE);
-	stat_print(STATS_MTA_SESSION, STAT_MAXACTIVE);
-
-	stat_print(STATS_LKA_SESSION, STAT_COUNT);
-	stat_print(STATS_LKA_SESSION, STAT_ACTIVE);
-	stat_print(STATS_LKA_SESSION, STAT_MAXACTIVE);
-	stat_print(STATS_LKA_SESSION_MX, STAT_COUNT);
-	stat_print(STATS_LKA_SESSION_HOST, STAT_COUNT);
-	stat_print(STATS_LKA_SESSION_CNAME, STAT_COUNT);
-	stat_print(STATS_LKA_FAILURE, STAT_COUNT);
-
-	printf("parent.uptime=%lld\n",
-	    (long long int) (time(NULL) - stats->parent.start));
-
-	stat_print(STATS_QUEUE_LOCAL, STAT_COUNT);
-	stat_print(STATS_QUEUE_REMOTE, STAT_COUNT);
-
-	stat_print(STATS_SCHEDULER, STAT_COUNT);
-	stat_print(STATS_SCHEDULER, STAT_ACTIVE);
-	stat_print(STATS_SCHEDULER, STAT_MAXACTIVE);
-
-	stat_print(STATS_SCHEDULER_BOUNCES, STAT_COUNT);
-	stat_print(STATS_SCHEDULER_BOUNCES, STAT_ACTIVE);
-	stat_print(STATS_SCHEDULER_BOUNCES, STAT_MAXACTIVE);
-
-	stat_print(STATS_RAMQUEUE_HOST, STAT_ACTIVE);
-	stat_print(STATS_RAMQUEUE_BATCH, STAT_ACTIVE);
-	stat_print(STATS_RAMQUEUE_MESSAGE, STAT_ACTIVE);
-	stat_print(STATS_RAMQUEUE_ENVELOPE, STAT_ACTIVE);
-
-	stat_print(STATS_RAMQUEUE_HOST, STAT_MAXACTIVE);
-	stat_print(STATS_RAMQUEUE_BATCH, STAT_MAXACTIVE);
-	stat_print(STATS_RAMQUEUE_MESSAGE, STAT_MAXACTIVE);
-	stat_print(STATS_RAMQUEUE_ENVELOPE, STAT_MAXACTIVE);
-
-	printf("smtp.errors.delays=%zd\n", stats->smtp.delays);
-	printf("smtp.errors.linetoolong=%zd\n", stats->smtp.linetoolong);
-	printf("smtp.errors.read_eof=%zd\n", stats->smtp.read_eof);
-	printf("smtp.errors.read_system=%zd\n", stats->smtp.read_error);
-	printf("smtp.errors.read_timeout=%zd\n", stats->smtp.read_timeout);
-	printf("smtp.errors.tempfail=%zd\n", stats->smtp.tempfail);
-	printf("smtp.errors.toofast=%zd\n", stats->smtp.toofast);
-	printf("smtp.errors.write_eof=%zd\n", stats->smtp.write_eof);
-	printf("smtp.errors.write_system=%zd\n", stats->smtp.write_error);
-	printf("smtp.errors.write_timeout=%zd\n", stats->smtp.write_timeout);
-
-	stat_print(STATS_SMTP_SESSION, STAT_COUNT);
-	stat_print(STATS_SMTP_SESSION_INET4, STAT_COUNT);
-	stat_print(STATS_SMTP_SESSION_INET6, STAT_COUNT);
-	printf("smtp.sessions.aborted=%zd\n", stats->smtp.read_eof +
-	    stats->smtp.read_error + stats->smtp.write_eof +
-	    stats->smtp.write_error);
-
-	stat_print(STATS_SMTP_SESSION, STAT_ACTIVE);
-	stat_print(STATS_SMTP_SESSION, STAT_MAXACTIVE);
-
-	printf("smtp.sessions.timeout=%zd\n", stats->smtp.read_timeout +
-	    stats->smtp.write_timeout);
-
-	stat_print(STATS_SMTP_SMTPS, STAT_COUNT);
-	stat_print(STATS_SMTP_SMTPS, STAT_ACTIVE);
-	stat_print(STATS_SMTP_SMTPS, STAT_MAXACTIVE);
-
-	stat_print(STATS_SMTP_STARTTLS, STAT_COUNT);
-	stat_print(STATS_SMTP_STARTTLS, STAT_ACTIVE);
-	stat_print(STATS_SMTP_STARTTLS, STAT_MAXACTIVE);
+	while (ibuf->w.queued)
+		if (msgbuf_write(&ibuf->w) < 0)
+			err(1, "write error");
 
-	return (1);
+	do {
+		if ((n = imsg_read(ibuf)) == -1)
+			errx(1, "imsg_read error");
+		if (n == 0)
+			errx(1, "pipe closed");
+
+		do {
+			if ((n = imsg_get(ibuf, &imsg)) == -1)
+				errx(1, "imsg_get error");
+			if (n == 0)
+				break;
+			if (imsg.hdr.type != IMSG_STATS_GET)
+				errx(1, "invalid imsg type");
+
+			kvp = imsg.data;
+			if (kvp->iter == NULL) {
+				imsg_free(&imsg);
+				return;
+			}
+
+			if (strcmp(kvp->key, "uptime") == 0)
+				printf("%s=%zd\n", kvp->key, time(NULL) - kvp->val);
+			else
+				printf("%s=%zd\n", kvp->key, kvp->val);
+
+			kv = *kvp;
+
+			imsg_free(&imsg);
+			goto again;
+
+		} while (n != 0);
+
+	} while (n != 0);
 }
 
 static void
diff --git a/usr.sbin/smtpd/smtpctl/Makefile b/usr.sbin/smtpd/smtpctl/Makefile
index aa80005a8d8..c55c89d1380 100644
--- a/usr.sbin/smtpd/smtpctl/Makefile
+++ b/usr.sbin/smtpd/smtpctl/Makefile
@@ -1,4 +1,4 @@
-#	$OpenBSD: Makefile,v 1.22 2012/01/11 22:24:37 gilles Exp $
+#	$OpenBSD: Makefile,v 1.23 2012/08/18 18:18:23 gilles Exp $
 
 .PATH:		${.CURDIR}/..
 
@@ -18,7 +18,7 @@ CFLAGS+=	-Wsign-compare -Wbounded
 
 SRCS=	enqueue.c parser.c log.c envelope.c
 SRCS+=	queue_backend.c queue_fsqueue.c
-SRCS+=	smtpctl.c stats.c util.c
+SRCS+=	smtpctl.c util.c
 
 LDADD+=	-lutil
 DPADD+=	${LIBUTIL} ${LIBEVENT}
diff --git a/usr.sbin/smtpd/smtpd.c b/usr.sbin/smtpd/smtpd.c
index 28cf891ed98..1d8e6e31d5e 100644
--- a/usr.sbin/smtpd/smtpd.c
+++ b/usr.sbin/smtpd/smtpd.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: smtpd.c,v 1.157 2012/08/09 09:48:02 eric Exp $	*/
+/*	$OpenBSD: smtpd.c,v 1.158 2012/08/18 18:18:23 gilles Exp $	*/
 
 /*
  * Copyright (c) 2008 Gilles Chehade <gilles@openbsd.org>
@@ -93,6 +93,7 @@ struct smtpd	*env = NULL;
 
 const char	*backend_queue = "fs";
 const char	*backend_scheduler = "ramqueue";
+const char	*backend_stat = "ram";
 
 static void
 parent_imsg(struct imsgev *iev, struct imsg *imsg)
@@ -454,6 +455,8 @@ main(int argc, char *argv[])
 				backend_queue = strchr(optarg, '=') + 1;
 			else if (strstr(optarg, "scheduler=") == optarg)
 				backend_scheduler = strchr(optarg, '=') + 1;
+			else if (strstr(optarg, "stat=") == optarg)
+				backend_stat = strchr(optarg, '=') + 1;
 			else
 				log_warnx("invalid backend specifier %s", optarg);
 			break;
@@ -486,6 +489,8 @@ main(int argc, char *argv[])
 				verbose |= TRACE_BOUNCE;
 			else if (!strcmp(optarg, "scheduler"))
 				verbose |= TRACE_SCHEDULER;
+			else if (!strcmp(optarg, "stat"))
+				verbose |= TRACE_STAT;
 			else if (!strcmp(optarg, "all"))
 				verbose |= ~TRACE_VERBOSE;
 			else
@@ -548,6 +553,7 @@ main(int argc, char *argv[])
 
 	log_debug("using \"%s\" queue backend", backend_queue);
 	log_debug("using \"%s\" scheduler backend", backend_scheduler);
+	log_debug("using \"%s\" stat backend", backend_stat);
 
 	env->sc_queue = queue_backend_lookup(backend_queue);
 	if (env->sc_queue == NULL)
@@ -556,6 +562,10 @@ main(int argc, char *argv[])
 	if (!env->sc_queue->init(1))
 		errx(1, "could not initialize queue backend");
 
+	env->sc_stat = stat_backend_lookup(backend_stat);
+	if (env->sc_stat == NULL)
+		errx(1, "could not find stat backend \"%s\"", backend_stat);
+
 	log_init(debug);
 	log_verbose(verbose);
 
@@ -567,15 +577,7 @@ main(int argc, char *argv[])
 
 	if (env->sc_hostname[0] == '\0')
 		errx(1, "machine does not have a hostname set");
-
-	env->stats = mmap(NULL, sizeof(struct stats), PROT_WRITE|PROT_READ,
-	    MAP_ANON|MAP_SHARED, -1, (off_t)0);
-	if (env->stats == MAP_FAILED)
-		fatal("mmap");
-	bzero(env->stats, sizeof(struct stats));
-	stat_init(env->stats->counters, STATS_MAX);
-
-	env->stats->parent.start = time(NULL);
+	env->sc_uptime = time(NULL);
 
 	fork_peers();
 
diff --git a/usr.sbin/smtpd/smtpd.h b/usr.sbin/smtpd/smtpd.h
index d0b0f7222fd..3feb220ecdb 100644
--- a/usr.sbin/smtpd/smtpd.h
+++ b/usr.sbin/smtpd/smtpd.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: smtpd.h,v 1.321 2012/08/18 15:45:12 eric Exp $	*/
+/*	$OpenBSD: smtpd.h,v 1.322 2012/08/18 18:18:23 gilles Exp $	*/
 
 /*
  * Copyright (c) 2008 Gilles Chehade <gilles@openbsd.org>
@@ -170,7 +170,6 @@ enum imsg_type {
 	IMSG_PARENT_AUTHENTICATE,
 	IMSG_PARENT_SEND_CONFIG,
 
-	IMSG_STATS,
 	IMSG_SMTP_ENQUEUE,
 	IMSG_SMTP_PAUSE,
 	IMSG_SMTP_RESUME,
@@ -178,7 +177,14 @@ enum imsg_type {
 	IMSG_DNS_HOST,
 	IMSG_DNS_HOST_END,
 	IMSG_DNS_MX,
-	IMSG_DNS_PTR
+	IMSG_DNS_PTR,
+
+	IMSG_STAT_INCREMENT,
+	IMSG_STAT_DECREMENT,
+	IMSG_STAT_SET,
+
+	IMSG_STATS,
+	IMSG_STATS_GET,
 };
 
 enum blockmodes {
@@ -587,6 +593,9 @@ struct smtpd {
 	char					 sc_hostname[MAXHOSTNAMELEN];
 	struct queue_backend			*sc_queue;
 	struct scheduler_backend		*sc_scheduler;
+	struct stat_backend			*sc_stat;
+
+	time_t					 sc_uptime;
 
 	TAILQ_HEAD(filterlist, filter)		*sc_filters;
 
@@ -600,7 +609,6 @@ struct smtpd {
 	SPLAY_HEAD(mfatree, mfa_session)	 mfa_sessions;
 	LIST_HEAD(mdalist, mda_session)		 mda_sessions;
 
-	struct stats				*stats;
 	u_int64_t				 filtermask;
 };
 
@@ -611,74 +619,8 @@ struct smtpd {
 #define	TRACE_MTA	0x0010
 #define	TRACE_BOUNCE	0x0020
 #define	TRACE_SCHEDULER	0x0040
+#define	TRACE_STAT	0x0080
 
-enum {
-	STATS_SMTP_SESSION = 0,
-	STATS_SMTP_SESSION_INET4,
-	STATS_SMTP_SESSION_INET6,
-	STATS_SMTP_SMTPS,
-	STATS_SMTP_STARTTLS,
-
-	STATS_MTA_SESSION,
-
-	STATS_MDA_SESSION,
-
-	STATS_CONTROL_SESSION,
-
-	STATS_LKA_SESSION,
-	STATS_LKA_SESSION_MX,
-	STATS_LKA_SESSION_HOST,
-	STATS_LKA_SESSION_CNAME,
-	STATS_LKA_FAILURE,
-
-	STATS_SCHEDULER,
-	STATS_SCHEDULER_BOUNCES,
-
-	STATS_QUEUE_LOCAL,
-	STATS_QUEUE_REMOTE,
-
-	STATS_RAMQUEUE_ENVELOPE,
-	STATS_RAMQUEUE_MESSAGE,
-	STATS_RAMQUEUE_BATCH,
-	STATS_RAMQUEUE_HOST,
-
-	STATS_MAX,
-};
-
-#define STAT_COUNT	0
-#define STAT_ACTIVE	1
-#define STAT_MAXACTIVE	2
-
-struct	stat_counter {
-	size_t	count;
-	size_t	active;
-	size_t	maxactive;
-};
-
-struct s_parent {
-	time_t		start;
-};
-
-struct s_session {
-	size_t		read_error;
-	size_t		read_timeout;
-	size_t		read_eof;
-	size_t		write_error;
-	size_t		write_timeout;
-	size_t		write_eof;
-	size_t		toofast;
-	size_t		tempfail;
-	size_t		linetoolong;
-	size_t		delays;
-};
-
-struct stats {
-	struct s_parent		 parent;
-	struct s_session	 mta;
-	struct s_session	 smtp;
-
-	struct stat_counter	 counters[STATS_MAX];
-};
 
 struct submit_status {
 	u_int64_t			 id;
@@ -954,6 +896,24 @@ struct scheduler_backend {
 	void	(*remove)(u_int64_t);
 };
 
+
+#define	STAT_KEY_SIZE	1024
+struct stat_kv {
+	void	*iter;
+	char	key[STAT_KEY_SIZE];
+	size_t	val;
+};
+
+struct stat_backend {
+	void	(*init)(void);
+	void	(*close)(void);
+	void	(*increment)(const char *);
+	void	(*decrement)(const char *);
+	void	(*set)(const char *, size_t);
+	int	(*iter)(void **, char **, size_t *);
+};
+
+
 extern struct smtpd	*env;
 extern void (*imsg_callback)(struct imsgev *, struct imsg *);
 
@@ -1118,7 +1078,7 @@ time_t scheduler_compute_schedule(struct scheduler_info *);
 /* smtp.c */
 pid_t smtp(void);
 void smtp_resume(void);
-
+void smtp_destroy(struct session *);
 
 /* smtp_session.c */
 void session_init(struct listener *, struct session *);
@@ -1159,11 +1119,12 @@ SPLAY_PROTOTYPE(ssltree, ssl, ssl_nodes, ssl_cmp);
 int	 ssl_ctx_use_private_key(void *, char *, off_t);
 int	 ssl_ctx_use_certificate_chain(void *, char *, off_t);
 
-/* stats.c */
-void	stat_init(struct stat_counter *, int);
-size_t	stat_get(int, int);
-size_t	stat_increment(int);
-size_t	stat_decrement(int);
+
+/* stat_backend.c */
+struct stat_backend	*stat_backend_lookup(const char *);
+void	stat_increment(const char *);
+void	stat_decrement(const char *);
+void	stat_set(const char *, size_t);
 
 
 /* tree.c */
diff --git a/usr.sbin/smtpd/smtpd/Makefile b/usr.sbin/smtpd/smtpd/Makefile
index 3d9467405e9..44fcb194fb5 100644
--- a/usr.sbin/smtpd/smtpd/Makefile
+++ b/usr.sbin/smtpd/smtpd/Makefile
@@ -1,4 +1,4 @@
-#	$OpenBSD: Makefile,v 1.46 2012/08/07 21:47:58 eric Exp $
+#	$OpenBSD: Makefile,v 1.47 2012/08/18 18:18:23 gilles Exp $
 
 .PATH:		${.CURDIR}/.. ${.CURDIR}/../../../lib/libc/asr
 
@@ -10,7 +10,8 @@ SRCS=		aliases.c auth.c bounce.c config.c control.c		\
 		mfa.c mfa_session.c mta.c mta_session.c	parse.y		\
 		queue.c queue_backend.c ruleset.c			\
 		scheduler.c scheduler_backend.c smtp.c smtp_session.c	\
-		smtpd.c	ssl.c ssl_privsep.c stats.c tree.c user.c util.c
+		smtpd.c	ssl.c ssl_privsep.c stat_backend.c tree.c	\
+		user.c util.c
 
 # backends
 SRCS+=		auth_bsd.c
@@ -24,6 +25,8 @@ SRCS+=		map_static.c
 SRCS+=		map_stdio.c
 SRCS+=		queue_fsqueue.c
 SRCS+=		scheduler_ramqueue.c
+SRCS+=		stat_ramstat.c
+#SRCS+=		stat_sqlite.c
 SRCS+=		user_pwd.c
 
 # resolver
diff --git a/usr.sbin/smtpd/stat_backend.c b/usr.sbin/smtpd/stat_backend.c
new file mode 100644
index 00000000000..b77ce3abc83
--- /dev/null
+++ b/usr.sbin/smtpd/stat_backend.c
@@ -0,0 +1,82 @@
+/*
+ * Copyright (c) 2012 Gilles Chehade <gilles@openbsd.org>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <sys/queue.h>
+#include <sys/tree.h>
+#include <sys/param.h>
+
+#include <event.h>
+#include <imsg.h>
+#include <stdio.h>
+#include <string.h>
+
+#include "log.h"
+#include "smtpd.h"
+
+struct stat_backend	stat_backend_ramstat;
+struct stat_backend	stat_backend_sqlite;
+
+struct stat_backend *
+stat_backend_lookup(const char *name)
+{
+	if (!strcmp(name, "ram"))
+		return &stat_backend_ramstat;
+
+	if (!strcmp(name, "sqlite"))
+		return &stat_backend_sqlite;
+
+	return (NULL);
+}
+
+void
+stat_increment(const char *name)
+{
+	char	key[STAT_KEY_SIZE];
+
+	if (strlcpy(key, name, sizeof key) >= sizeof key)
+		log_warn("stat_increment: truncated key '%s', ignored", name);
+
+	imsg_compose_event(env->sc_ievs[PROC_CONTROL],
+	    IMSG_STAT_INCREMENT, 0, 0, -1, key, sizeof key);
+}
+
+void
+stat_decrement(const char *name)
+{
+	char	key[STAT_KEY_SIZE];
+
+	if (strlcpy(key, name, sizeof key) >= sizeof key)
+		log_warn("stat_increment: truncated key '%s', ignored", name);
+
+	imsg_compose_event(env->sc_ievs[PROC_CONTROL],
+	    IMSG_STAT_DECREMENT, 0, 0, -1, key, sizeof key);
+}
+
+void
+stat_set(const char *name, size_t value)
+{
+	struct stat_kv	kv;
+
+	bzero(&kv, sizeof kv);
+	if (strlcpy(kv.key, name, sizeof kv.key) >= sizeof kv.key)
+		log_warn("stat_increment: truncated key '%s', ignored", name);
+	kv.val = value;
+
+	imsg_compose_event(env->sc_ievs[PROC_CONTROL],
+	    IMSG_STAT_SET, 0, 0, -1, &kv, sizeof kv);
+}
diff --git a/usr.sbin/smtpd/stat_ramstat.c b/usr.sbin/smtpd/stat_ramstat.c
new file mode 100644
index 00000000000..996f8ff8a24
--- /dev/null
+++ b/usr.sbin/smtpd/stat_ramstat.c
@@ -0,0 +1,165 @@
+/*
+ * Copyright (c) 2012 Gilles Chehade <gilles@openbsd.org>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <sys/queue.h>
+#include <sys/tree.h>
+#include <sys/param.h>
+
+#include <event.h>
+#include <imsg.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "smtpd.h"
+#include "log.h"
+
+
+static void	ramstat_init(void);
+static void	ramstat_close(void);
+static void	ramstat_increment(const char *);
+static void	ramstat_decrement(const char *);
+static void	ramstat_set(const char *, size_t);
+static int	ramstat_iter(void **, char **, size_t *);
+
+struct ramstat_entry {
+	RB_ENTRY(ramstat_entry)	entry;
+	
+	char	key[STAT_KEY_SIZE];
+	size_t	value;
+};
+RB_HEAD(stats_tree, ramstat_entry)	stats;
+RB_PROTOTYPE(stats_tree, ramstat_entry, entry, ramstat_entry_cmp);
+
+struct stat_backend	stat_backend_ramstat = {
+	ramstat_init,
+	ramstat_close,
+	ramstat_increment,
+	ramstat_decrement,
+	ramstat_set,
+	ramstat_iter
+};
+
+static void
+ramstat_init(void)
+{
+	log_trace(TRACE_STAT, "ramstat: init");
+	RB_INIT(&stats);
+
+	/* ramstat_set() should be called for each key we want
+	 * to have displayed by smtpctl show stats at startup.
+	 */
+	ramstat_set("uptime", env->sc_uptime);
+}
+
+static void
+ramstat_close(void)
+{
+	log_trace(TRACE_STAT, "ramstat: close");
+}
+
+static void
+ramstat_increment(const char *name)
+{
+	struct ramstat_entry	*np, lk;
+
+	log_trace(TRACE_STAT, "ramstat: increment: %s", name);
+	strlcpy(lk.key, name, sizeof (lk.key));
+	np = RB_FIND(stats_tree, &stats, &lk);
+	if (np == NULL) {
+		np = calloc(1, sizeof *np);
+		if (np == NULL)
+			fatal("calloc");
+		strlcpy(np->key, name, sizeof (np->key));
+		RB_INSERT(stats_tree, &stats, np);
+	}
+	log_trace(TRACE_STAT, "ramstat: %s (%p): %d -> %d",
+	    name, name, (int)np->value, (int)np->value + 1);
+	np->value++;
+}
+
+static void
+ramstat_decrement(const char *name)
+{
+	struct ramstat_entry	*np, lk;
+
+	log_trace(TRACE_STAT, "ramstat: decrement: %s", name);
+	strlcpy(lk.key, name, sizeof (lk.key));
+	np = RB_FIND(stats_tree, &stats, &lk);
+	if (np == NULL) {
+		np = calloc(1, sizeof *np);
+		if (np == NULL)
+			fatal("calloc");
+		strlcpy(np->key, name, sizeof (np->key));
+		RB_INSERT(stats_tree, &stats, np);
+	}
+	log_trace(TRACE_STAT, "ramstat: %s (%p): %d -> %d",
+	    name, name, (int)np->value, (int)np->value - 1);
+	np->value--;
+}
+
+static void
+ramstat_set(const char *name, size_t val)
+{
+	struct ramstat_entry	*np, lk;
+
+	log_trace(TRACE_STAT, "ramstat: set");
+	strlcpy(lk.key, name, sizeof (lk.key));
+	np = RB_FIND(stats_tree, &stats, &lk);
+	if (np == NULL) {
+		np = calloc(1, sizeof *np);
+		if (np == NULL)
+			fatal("calloc");
+		strlcpy(np->key, name, sizeof (np->key));
+		RB_INSERT(stats_tree, &stats, np);
+	}
+	log_trace(TRACE_STAT, "ramstat: %s: %d -> %d",
+	    name, (int)np->value, (int)val);
+	np->value = val;
+}
+
+static int
+ramstat_iter(void **iter, char **name, size_t *val)
+{
+	struct ramstat_entry *np;
+
+	log_trace(TRACE_STAT, "ramstat: iter");
+	if (RB_EMPTY(&stats))
+		return 0;
+
+	if (*iter == NULL)
+		np = RB_ROOT(&stats);
+	else
+		np = RB_NEXT(stats_tree, &stats, *iter);
+
+	if (np) {
+		*name = np->key;
+		*val  = np->value;
+	}
+	*iter = np;
+	return 1;
+}
+
+
+static int
+ramstat_entry_cmp(struct ramstat_entry *e1, struct ramstat_entry *e2)
+{
+	return strcmp(e1->key, e2->key);
+}
+
+RB_GENERATE(stats_tree, ramstat_entry, entry, ramstat_entry_cmp);
diff --git a/usr.sbin/smtpd/stats.c b/usr.sbin/smtpd/stats.c
index fb9715d2ddb..e69de29bb2d 100644
--- a/usr.sbin/smtpd/stats.c
+++ b/usr.sbin/smtpd/stats.c
@@ -1,79 +0,0 @@
-/*
- * Copyright (c) 2011 Eric Faurot <eric@openbsd.org>
- *
- * Permission to use, copy, modify, and distribute this software for any
- * purpose with or without fee is hereby granted, provided that the above
- * copyright notice and this permission notice appear in all copies.
- *
- * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
- * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
- * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
- * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
- * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
- * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
- * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
- */
-
-#include <sys/types.h>
-#include <sys/socket.h>
-#include <sys/queue.h>
-#include <sys/tree.h>
-#include <sys/param.h>
-
-#include <event.h>
-#include <imsg.h>
-#include <stdio.h>
-
-#include "smtpd.h"
-
-static struct stat_counter	*counters = NULL;
-static int			 ncounter = 0;
-
-void
-stat_init(struct stat_counter *c, int n)
-{
-	counters = c;
-	ncounter = n;
-}
-
-size_t
-stat_increment(int stat)
-{
-	if (stat < 0 || stat >= ncounter)
-		return (-1);
-
-	counters[stat].count++;
-	if (++counters[stat].active > counters[stat].maxactive)
-		counters[stat].maxactive = counters[stat].active;
-
-	return (counters[stat].active);
-}
-
-size_t
-stat_decrement(int stat)
-{
-	if (stat < 0 || stat >= ncounter)
-		return (-1);
-
-	counters[stat].active--;
-
-	return (counters[stat].active);
-}
-
-size_t
-stat_get(int stat, int what)
-{
-	if (stat < 0 || stat >= ncounter)
-		return (-1);
-
-	switch (what) {
-	case STAT_COUNT:
-		return counters[stat].count;
-	case STAT_ACTIVE:
-		return counters[stat].active;
-	case STAT_MAXACTIVE:
-		return counters[stat].maxactive;
-	default:
-		return (-1);
-	}
-}