Transition MWI to Stasis-core

Remove MWI's dependency on the event system by moving it to
Stasis-core. This also introduces forwarding topic pools in Stasis-core
which aggregate many dynamically allocated topics into a single primary
topic.

Review: https://reviewboard.asterisk.org/r/2368/
(closes issue ASTERISK-21097)
Patch-by: Kinsey Moore


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@383284 65c4cc65-6c06-0410-ace0-fbb531ad65f3

9 files changed, 199 insertions, 150 deletions

diff --git a/channels/chan_dahdi.c b/channels/chan_dahdi.c
index e077e8422..15075ebf2 100644
--- a/channels/chan_dahdi.c
+++ b/channels/chan_dahdi.c
@@ -502,7 +502,7 @@ static enum ast_bridge_result dahdi_bridge(struct ast_channel *c0, struct ast_ch
 
 static int dahdi_sendtext(struct ast_channel *c, const char *text);
 
-static void mwi_event_cb(const struct ast_event *event, void *userdata)
+static void mwi_event_cb(void *userdata, struct stasis_subscription *sub, struct stasis_topic *topic, struct stasis_message *msg)
 {
 	/* This module does not handle MWI in an event-based manner.  However, it
 	 * subscribes to MWI for each mailbox that is configured so that the core
@@ -1215,7 +1215,7 @@ struct dahdi_pvt {
 	 */
 	char mailbox[AST_MAX_EXTENSION];
 	/*! \brief Opaque event subscription parameters for message waiting indication support. */
-	struct ast_event_sub *mwi_event_sub;
+	struct stasis_subscription *mwi_event_sub;
 	/*! \brief Delayed dialing for E911.  Overlap digits for ISDN. */
 	char dialdest[256];
 #ifdef HAVE_DAHDI_LINEREVERSE_VMWI
@@ -3753,7 +3753,6 @@ struct sig_ss7_callback sig_ss7_callbacks =
 static void notify_message(char *mailbox_full, int thereornot)
 {
 	char s[sizeof(mwimonitornotify) + 80];
-	struct ast_event *event;
 	char *mailbox, *context;
 
 	/* Strip off @default */
@@ -3762,16 +3761,7 @@ static void notify_message(char *mailbox_full, int thereornot)
 	if (ast_strlen_zero(context))
 		context = "default";
 
-	if (!(event = ast_event_new(AST_EVENT_MWI,
-			AST_EVENT_IE_MAILBOX, AST_EVENT_IE_PLTYPE_STR, mailbox,
-			AST_EVENT_IE_CONTEXT, AST_EVENT_IE_PLTYPE_STR, context,
-			AST_EVENT_IE_NEWMSGS, AST_EVENT_IE_PLTYPE_UINT, thereornot,
-			AST_EVENT_IE_OLDMSGS, AST_EVENT_IE_PLTYPE_UINT, thereornot,
-			AST_EVENT_IE_END))) {
-		return;
-	}
-
-	ast_event_queue_and_cache(event);
+	stasis_publish_mwi_state(mailbox, context, thereornot, thereornot);
 
 	if (!ast_strlen_zero(mailbox) && !ast_strlen_zero(mwimonitornotify)) {
 		snprintf(s, sizeof(s), "%s %s %d", mwimonitornotify, mailbox, thereornot);
@@ -5413,24 +5403,25 @@ static int send_cwcidspill(struct dahdi_pvt *p)
 static int has_voicemail(struct dahdi_pvt *p)
 {
 	int new_msgs;
-	struct ast_event *event;
 	char *mailbox, *context;
+	RAII_VAR(struct stasis_message *, mwi_message, NULL, ao2_cleanup);
+	struct ast_str *uniqueid = ast_str_alloca(AST_MAX_MAILBOX_UNIQUEID);
 
 	mailbox = context = ast_strdupa(p->mailbox);
 	strsep(&context, "@");
-	if (ast_strlen_zero(context))
+	if (ast_strlen_zero(context)) {
 		context = "default";
+	}
 
-	event = ast_event_get_cached(AST_EVENT_MWI,
-		AST_EVENT_IE_MAILBOX, AST_EVENT_IE_PLTYPE_STR, mailbox,
-		AST_EVENT_IE_CONTEXT, AST_EVENT_IE_PLTYPE_STR, context,
-		AST_EVENT_IE_END);
+	ast_str_set(&uniqueid, 0, "%s@%s", mailbox, context);
+	mwi_message = stasis_cache_get(stasis_mwi_topic_cached(), stasis_mwi_state_message(), ast_str_buffer(uniqueid));
 
-	if (event) {
-		new_msgs = ast_event_get_ie_uint(event, AST_EVENT_IE_NEWMSGS);
-		ast_event_destroy(event);
-	} else
+	if (mwi_message) {
+		struct stasis_mwi_state *mwi_state = stasis_message_data(mwi_message);
+		new_msgs = mwi_state->new_msgs;
+	} else {
 		new_msgs = ast_app_has_voicemail(p->mailbox, NULL);
+	}
 
 	return new_msgs;
 }
@@ -5965,10 +5956,12 @@ static void destroy_dahdi_pvt(struct dahdi_pvt *pvt)
 		}
 	}
 	ast_free(p->cidspill);
-	if (p->use_smdi)
+	if (p->use_smdi) {
 		ast_smdi_interface_unref(p->smdi_iface);
-	if (p->mwi_event_sub)
-		ast_event_unsubscribe(p->mwi_event_sub);
+	}
+	if (p->mwi_event_sub) {
+		p->mwi_event_sub = stasis_unsubscribe(p->mwi_event_sub);
+	}
 	if (p->vars) {
 		ast_variables_destroy(p->vars);
 	}
@@ -5981,8 +5974,9 @@ static void destroy_dahdi_pvt(struct dahdi_pvt *pvt)
 
 	ast_mutex_destroy(&p->lock);
 	dahdi_close_sub(p, SUB_REAL);
-	if (p->owner)
+	if (p->owner) {
 		ast_channel_tech_pvt_set(p->owner, NULL);
+	}
 	ast_free(p);
 }
 
@@ -13226,15 +13220,20 @@ static struct dahdi_pvt *mkintf(int channel, const struct dahdi_chan_conf *conf,
 		ast_copy_string(tmp->mailbox, conf->chan.mailbox, sizeof(tmp->mailbox));
 		if (channel != CHAN_PSEUDO && !ast_strlen_zero(tmp->mailbox)) {
 			char *mailbox, *context;
+			struct ast_str *uniqueid = ast_str_alloca(AST_MAX_MAILBOX_UNIQUEID);
+			struct stasis_topic *mailbox_specific_topic;
+
 			mailbox = context = ast_strdupa(tmp->mailbox);
 			strsep(&context, "@");
 			if (ast_strlen_zero(context))
 				context = "default";
-			tmp->mwi_event_sub = ast_event_subscribe(AST_EVENT_MWI, mwi_event_cb, "Dahdi MWI subscription", NULL,
-				AST_EVENT_IE_MAILBOX, AST_EVENT_IE_PLTYPE_STR, mailbox,
-				AST_EVENT_IE_CONTEXT, AST_EVENT_IE_PLTYPE_STR, context,
-				AST_EVENT_IE_NEWMSGS, AST_EVENT_IE_PLTYPE_EXISTS,
-				AST_EVENT_IE_END);
+
+			ast_str_set(&uniqueid, 0, "%s@%s", mailbox, context);
+
+			mailbox_specific_topic = stasis_mwi_topic(ast_str_buffer(uniqueid));
+			if (mailbox_specific_topic) {
+				tmp->mwi_event_sub = stasis_subscribe(mailbox_specific_topic, mwi_event_cb, NULL);
+			}
 		}
 #ifdef HAVE_DAHDI_LINEREVERSE_VMWI
 		tmp->mwisend_setting = conf->chan.mwisend_setting;
diff --git a/channels/chan_iax2.c b/channels/chan_iax2.c
index 5a307bf0c..7280c480e 100644
--- a/channels/chan_iax2.c
+++ b/channels/chan_iax2.c
@@ -533,7 +533,7 @@ struct iax2_peer {
 
 	int expire;					/*!< Schedule entry for expiry */
 	int expiry;					/*!< How soon to expire */
-	iax2_format capability;        /*!< Capability */
+	iax2_format capability;				/*!< Capability */
 
 	/* Qualification */
 	int callno;					/*!< Call number of POKE request */
@@ -545,12 +545,12 @@ struct iax2_peer {
 	int pokefreqnotok;				/*!< How often to check when the host has been determined to be down */
 	int historicms;					/*!< How long recent average responses took */
 	int smoothing;					/*!< Sample over how many units to determine historic ms */
-	uint16_t maxcallno;					/*!< Max call number limit for this peer.  Set on registration */
+	uint16_t maxcallno;				/*!< Max call number limit for this peer.  Set on registration */
 
-	struct ast_event_sub *mwi_event_sub;
+	struct stasis_subscription *mwi_event_sub;	/*!< This subscription lets pollmailboxes know which mailboxes need to be polled */
 
 	struct ast_acl_list *acl;
-	enum calltoken_peer_enum calltoken_required;        /*!< Is calltoken validation required or not, can be YES, NO, or AUTO */
+	enum calltoken_peer_enum calltoken_required;	/*!< Is calltoken validation required or not, can be YES, NO, or AUTO */
 };
 
 #define IAX2_TRUNK_PREFACE (sizeof(struct iax_frame) + sizeof(struct ast_iax2_meta_hdr) + sizeof(struct ast_iax2_meta_trunk_hdr))
@@ -1316,7 +1316,7 @@ static void iax2_lock_owner(int callno)
 	}
 }
 
-static void mwi_event_cb(const struct ast_event *event, void *userdata)
+static void mwi_event_cb(void *userdata, struct stasis_subscription *sub, struct stasis_topic *topic, struct stasis_message *msg)
 {
 	/* The MWI subscriptions exist just so the core knows we care about those
 	 * mailboxes.  However, we just grab the events out of the cache when it
@@ -8743,23 +8743,24 @@ static int update_registry(struct sockaddr_in *sin, int callno, char *devtype, i
 		iax_ie_append_short(&ied, IAX_IE_REFRESH, p->expiry);
 		iax_ie_append_addr(&ied, IAX_IE_APPARENT_ADDR, &peer_addr);
 		if (!ast_strlen_zero(p->mailbox)) {
-			struct ast_event *event;
 			int new, old;
 			char *mailbox, *context;
+			RAII_VAR(struct stasis_message *, msg, NULL, ao2_cleanup);
+			struct ast_str *uniqueid = ast_str_alloca(AST_MAX_MAILBOX_UNIQUEID);
 
 			context = mailbox = ast_strdupa(p->mailbox);
 			strsep(&context, "@");
-			if (ast_strlen_zero(context))
+			if (ast_strlen_zero(context)) {
 				context = "default";
+			}
+
+			ast_str_set(&uniqueid, 0, "%s@%s", mailbox, context);
+			msg = stasis_cache_get(stasis_mwi_topic_cached(), stasis_mwi_state_message(), ast_str_buffer(uniqueid));
 
-			event = ast_event_get_cached(AST_EVENT_MWI,
-				AST_EVENT_IE_MAILBOX, AST_EVENT_IE_PLTYPE_STR, mailbox,
-				AST_EVENT_IE_CONTEXT, AST_EVENT_IE_PLTYPE_STR, context,
-				AST_EVENT_IE_END);
-			if (event) {
-				new = ast_event_get_ie_uint(event, AST_EVENT_IE_NEWMSGS);
-				old = ast_event_get_ie_uint(event, AST_EVENT_IE_OLDMSGS);
-				ast_event_destroy(event);
+			if (msg) {
+				struct stasis_mwi_state *mwi_state = stasis_message_data(msg);
+				new = mwi_state->new_msgs;
+				old = mwi_state->old_msgs;
 			} else { /* Fall back on checking the mailbox directly */
 				ast_app_inboxcount(p->mailbox, &new, &old);
 			}
@@ -12392,8 +12393,9 @@ static void peer_destructor(void *obj)
 	if (peer->dnsmgr)
 		ast_dnsmgr_release(peer->dnsmgr);
 
-	if (peer->mwi_event_sub)
-		ast_event_unsubscribe(peer->mwi_event_sub);
+	if (peer->mwi_event_sub) {
+		peer->mwi_event_sub = stasis_unsubscribe(peer->mwi_event_sub);
+	}
 
 	ast_string_field_free_memory(peer);
 }
@@ -12667,14 +12669,21 @@ static struct iax2_peer *build_peer(const char *name, struct ast_variable *v, st
 
 	if (!ast_strlen_zero(peer->mailbox)) {
 		char *mailbox, *context;
+		struct ast_str *uniqueid = ast_str_alloca(AST_MAX_MAILBOX_UNIQUEID);
+		struct stasis_topic *mailbox_specific_topic;
+
 		context = mailbox = ast_strdupa(peer->mailbox);
 		strsep(&context, "@");
-		if (ast_strlen_zero(context))
+		if (ast_strlen_zero(context)) {
 			context = "default";
-		peer->mwi_event_sub = ast_event_subscribe(AST_EVENT_MWI, mwi_event_cb, "IAX MWI subscription", NULL,
-			AST_EVENT_IE_MAILBOX, AST_EVENT_IE_PLTYPE_STR, mailbox,
-			AST_EVENT_IE_CONTEXT, AST_EVENT_IE_PLTYPE_STR, context,
-			AST_EVENT_IE_END);
+		}
+
+		ast_str_set(&uniqueid, 0, "%s@%s", mailbox, context);
+
+		mailbox_specific_topic = stasis_mwi_topic(ast_str_buffer(uniqueid));
+		if (mailbox_specific_topic) {
+			peer->mwi_event_sub = stasis_subscribe(mailbox_specific_topic, mwi_event_cb, NULL);
+		}
 	}
 
 	if (subscribe_acl_change) {
diff --git a/channels/chan_mgcp.c b/channels/chan_mgcp.c
index 0c3dac607..65a53900e 100644
--- a/channels/chan_mgcp.c
+++ b/channels/chan_mgcp.c
@@ -82,6 +82,7 @@ ASTERISK_FILE_VERSION(__FILE__, "$Revision$")
 #include "asterisk/event.h"
 #include "asterisk/chanvars.h"
 #include "asterisk/pktccops.h"
+#include "asterisk/stasis.h"
 
 /*
  * Define to work around buggy dlink MGCP phone firmware which
@@ -342,7 +343,7 @@ struct mgcp_endpoint {
 	char curtone[80];			/*!< Current tone */
 	char mailbox[AST_MAX_EXTENSION];
 	char parkinglot[AST_MAX_CONTEXT];   /*!< Parkinglot */
-	struct ast_event_sub *mwi_event_sub;
+	struct stasis_subscription *mwi_event_sub;
 	ast_group_t callgroup;
 	ast_group_t pickupgroup;
 	int callwaiting;
@@ -483,7 +484,7 @@ static struct ast_channel_tech mgcp_tech = {
 	.func_channel_read = acf_channel_read,
 };
 
-static void mwi_event_cb(const struct ast_event *event, void *userdata)
+static void mwi_event_cb(void *userdata, struct stasis_subscription *sub, struct stasis_topic *topic, struct stasis_message *msg)
 {
 	/* This module does not handle MWI in an event-based manner.  However, it
 	 * subscribes to MWI for each mailbox that is configured so that the core
@@ -494,24 +495,26 @@ static void mwi_event_cb(const struct ast_event *event, void *userdata)
 static int has_voicemail(struct mgcp_endpoint *p)
 {
 	int new_msgs;
-	struct ast_event *event;
+	RAII_VAR(struct stasis_message *, msg, NULL, ao2_cleanup);
+	struct ast_str *uniqueid = ast_str_alloca(AST_MAX_MAILBOX_UNIQUEID);
 	char *mbox, *cntx;
 
 	cntx = mbox = ast_strdupa(p->mailbox);
 	strsep(&cntx, "@");
-	if (ast_strlen_zero(cntx))
+	if (ast_strlen_zero(cntx)) {
 		cntx = "default";
+	}
 
-	event = ast_event_get_cached(AST_EVENT_MWI,
-		AST_EVENT_IE_MAILBOX, AST_EVENT_IE_PLTYPE_STR, mbox,
-		AST_EVENT_IE_CONTEXT, AST_EVENT_IE_PLTYPE_STR, cntx,
-		AST_EVENT_IE_END);
+	ast_str_set(&uniqueid, 0, "%s@%s", mbox, cntx);
 
-	if (event) {
-		new_msgs = ast_event_get_ie_uint(event, AST_EVENT_IE_NEWMSGS);
-		ast_event_destroy(event);
-	} else
+	msg = stasis_cache_get(stasis_mwi_topic_cached(), stasis_mwi_state(), ast_str_buffer(uniqueid));
+
+	if (msg) {
+		struct stasis_mwi_state *mwi_state = stasis_message_data(msg);
+		new_msgs = mwi_state->new_msgs;
+	} else {
 		new_msgs = ast_app_has_voicemail(p->mailbox, NULL);
+	}
 
 	return new_msgs;
 }
@@ -3972,6 +3975,7 @@ static struct mgcp_gateway *build_gateway(char *cat, struct ast_variable *v)
 	struct mgcp_endpoint *e;
 	struct mgcp_subchannel *sub;
 	struct ast_variable *chanvars = NULL;
+	struct ast_str *uniqueid = ast_str_alloca(AST_MAX_MAILBOX_UNIQUEID);
 
 	/*char txident[80];*/
 	int i=0, y=0;
@@ -4168,16 +4172,20 @@ static struct mgcp_gateway *build_gateway(char *cat, struct ast_variable *v)
 				ast_copy_string(e->parkinglot, parkinglot, sizeof(e->parkinglot));
 				if (!ast_strlen_zero(e->mailbox)) {
 					char *mbox, *cntx;
+					struct stasis_topic *mailbox_specific_topic;
+
 					cntx = mbox = ast_strdupa(e->mailbox);
 					strsep(&cntx, "@");
 					if (ast_strlen_zero(cntx)) {
 						cntx = "default";
 					}
-					e->mwi_event_sub = ast_event_subscribe(AST_EVENT_MWI, mwi_event_cb, "MGCP MWI subscription", NULL,
-						AST_EVENT_IE_MAILBOX, AST_EVENT_IE_PLTYPE_STR, mbox,
-						AST_EVENT_IE_CONTEXT, AST_EVENT_IE_PLTYPE_STR, cntx,
-						AST_EVENT_IE_NEWMSGS, AST_EVENT_IE_PLTYPE_EXISTS,
-						AST_EVENT_IE_END);
+					ast_str_reset(uniqueid);
+					ast_str_set(&uniqueid, 0, "%s@%s", mbox, cntx);
+
+					maibox_specific_topic = stasis_mwi_topic(ast_str_buffer(uniqueid));
+					if (mailbox_specific_topic) {
+						e->mwi_event_sub = stasis_subscribe(mailbox_specific_topic, mwi_event_cb, NULL);
+					}
 				}
 				snprintf(e->rqnt_ident, sizeof(e->rqnt_ident), "%08lx", ast_random());
 				e->msgstate = -1;
@@ -4516,8 +4524,9 @@ static void destroy_endpoint(struct mgcp_endpoint *e)
 		ast_free(s);
 	}
 
-	if (e->mwi_event_sub)
-		ast_event_unsubscribe(e->mwi_event_sub);
+	if (e->mwi_event_sub) {
+		e->mwi_event_sub = stasis_unsubscribe(e->mwi_event_sub);
+	}
 
 	if (e->chanvars) {
 		ast_variables_destroy(e->chanvars);
diff --git a/channels/chan_sip.c b/channels/chan_sip.c
index 631c1db5d..28e8d4d35 100644
--- a/channels/chan_sip.c
+++ b/channels/chan_sip.c
@@ -294,6 +294,7 @@ ASTERISK_FILE_VERSION(__FILE__, "$Revision$")
 #include "sip/include/dialplan_functions.h"
 #include "sip/include/security_events.h"
 #include "asterisk/sip_api.h"
+#include "asterisk/app.h"
 
 /*** DOCUMENTATION
 	<application name="SIPDtmfMode" language="en_US">
@@ -1275,7 +1276,7 @@ static int sip_poke_noanswer(const void *data);
 static int sip_poke_peer(struct sip_peer *peer, int force);
 static void sip_poke_all_peers(void);
 static void sip_peer_hold(struct sip_pvt *p, int hold);
-static void mwi_event_cb(const struct ast_event *, void *);
+static void mwi_event_cb(void *, struct stasis_subscription *, struct stasis_topic *, struct stasis_message *);
 static void network_change_event_cb(const struct ast_event *, void *);
 static void acl_change_event_cb(const struct ast_event *event, void *userdata);
 static void sip_keepalive_all_peers(void);
@@ -5225,8 +5226,9 @@ static void register_peer_exten(struct sip_peer *peer, int onoff)
 /*! Destroy mailbox subscriptions */
 static void destroy_mailbox(struct sip_mailbox *mailbox)
 {
-	if (mailbox->event_sub)
-		ast_event_unsubscribe(mailbox->event_sub);
+	if (mailbox->event_sub) {
+		mailbox->event_sub = stasis_unsubscribe(mailbox->event_sub);
+	}
 	ast_free(mailbox);
 }
 
@@ -16644,11 +16646,16 @@ static void sip_peer_hold(struct sip_pvt *p, int hold)
 }
 
 /*! \brief Receive MWI events that we have subscribed to */
-static void mwi_event_cb(const struct ast_event *event, void *userdata)
+static void mwi_event_cb(void *userdata, struct stasis_subscription *sub, struct stasis_topic *topic, struct stasis_message *msg)
 {
 	struct sip_peer *peer = userdata;
-
-	sip_send_mwi_to_peer(peer, 0);
+	if (stasis_subscription_final_message(sub, msg)) {
+		ao2_cleanup(peer);
+		return;
+	}
+	if (stasis_mwi_state_message() == stasis_message_type(msg)) {
+		sip_send_mwi_to_peer(peer, 0);
+	}
 }
 
 static void network_change_event_subscribe(void)
@@ -24787,16 +24794,9 @@ static int handle_request_notify(struct sip_pvt *p, struct sip_request *req, str
 		if (!ast_strlen_zero(mailbox) && !ast_strlen_zero(c)) {
 			char *old = strsep(&c, " ");
 			char *new = strsep(&old, "/");
-			struct ast_event *event;
 
-			if ((event = ast_event_new(AST_EVENT_MWI,
-						   AST_EVENT_IE_MAILBOX, AST_EVENT_IE_PLTYPE_STR, mailbox,
-						   AST_EVENT_IE_CONTEXT, AST_EVENT_IE_PLTYPE_STR, "SIP_Remote",
-						   AST_EVENT_IE_NEWMSGS, AST_EVENT_IE_PLTYPE_UINT, atoi(new),
-						   AST_EVENT_IE_OLDMSGS, AST_EVENT_IE_PLTYPE_UINT, atoi(old),
-						   AST_EVENT_IE_END))) {
-				ast_event_queue_and_cache(event);
-			}
+			stasis_publish_mwi_state(mailbox, "SIP_Remote", atoi(new), atoi(old));
+
 			transmit_response(p, "200 OK", req);
 		} else {
 			transmit_response(p, "489 Bad event", req);
@@ -27617,16 +27617,20 @@ static int handle_request_publish(struct sip_pvt *p, struct sip_request *req, st
 static void add_peer_mwi_subs(struct sip_peer *peer)
 {
 	struct sip_mailbox *mailbox;
+	struct ast_str *uniqueid = ast_str_alloca(AST_MAX_MAILBOX_UNIQUEID);
 
 	AST_LIST_TRAVERSE(&peer->mailboxes, mailbox, entry) {
-		if (mailbox->event_sub) {
-			ast_event_unsubscribe(mailbox->event_sub);
-		}
+		struct stasis_topic *mailbox_specific_topic;
+		mailbox->event_sub = stasis_unsubscribe(mailbox->event_sub);
+
+		ast_str_reset(uniqueid);
+		ast_str_set(&uniqueid, 0, "%s@%s", mailbox->mailbox, S_OR(mailbox->context, "default"));
 
-		mailbox->event_sub = ast_event_subscribe(AST_EVENT_MWI, mwi_event_cb, "SIP mbox event", peer,
-			AST_EVENT_IE_MAILBOX, AST_EVENT_IE_PLTYPE_STR, mailbox->mailbox,
-			AST_EVENT_IE_CONTEXT, AST_EVENT_IE_PLTYPE_STR, S_OR(mailbox->context, "default"),
-			AST_EVENT_IE_END);
+		mailbox_specific_topic = stasis_mwi_topic(ast_str_buffer(uniqueid));
+		if (mailbox_specific_topic) {
+			ao2_ref(peer, +1);
+			mailbox->event_sub = stasis_subscribe(mailbox_specific_topic, mwi_event_cb, peer);
+		}
 	}
 }
 
@@ -28832,19 +28836,24 @@ static int get_cached_mwi(struct sip_peer *peer, int *new, int *old)
 {
 	struct sip_mailbox *mailbox;
 	int in_cache;
+	struct ast_str *uniqueid = ast_str_alloca(AST_MAX_MAILBOX_UNIQUEID);
 
 	in_cache = 0;
 	AST_LIST_TRAVERSE(&peer->mailboxes, mailbox, entry) {
-		struct ast_event *event;
-		event = ast_event_get_cached(AST_EVENT_MWI,
-			AST_EVENT_IE_MAILBOX, AST_EVENT_IE_PLTYPE_STR, mailbox->mailbox,
-			AST_EVENT_IE_CONTEXT, AST_EVENT_IE_PLTYPE_STR, S_OR(mailbox->context, "default"),
-			AST_EVENT_IE_END);
-		if (!event)
+		RAII_VAR(struct stasis_message *, msg, NULL, ao2_cleanup);
+		struct stasis_mwi_state *mwi_state;
+
+		ast_str_reset(uniqueid);
+		ast_str_set(&uniqueid, 0, "%s@%s", mailbox->mailbox, S_OR(mailbox->context, "default"));
+
+		msg = stasis_cache_get(stasis_mwi_topic_cached(), stasis_mwi_state_message(), ast_str_buffer(uniqueid));
+		if (!msg) {
 			continue;
-		*new += ast_event_get_ie_uint(event, AST_EVENT_IE_NEWMSGS);
-		*old += ast_event_get_ie_uint(event, AST_EVENT_IE_OLDMSGS);
-		ast_event_destroy(event);
+		}
+
+		mwi_state = stasis_message_data(msg);
+		*new += mwi_state->new_msgs;
+		*old += mwi_state->old_msgs;
 		in_cache = 1;
 	}
 
diff --git a/channels/chan_skinny.c b/channels/chan_skinny.c
index c974caee8..6045a09f0 100644
--- a/channels/chan_skinny.c
+++ b/channels/chan_skinny.c
@@ -1442,7 +1442,7 @@ struct skinny_line {
 	SKINNY_LINE_OPTIONS
 	ast_mutex_t lock;
 	struct skinny_container *container;
-	struct ast_event_sub *mwi_event_sub; /* Event based MWI */
+	struct stasis_subscription *mwi_event_sub; /* Event based MWI */
 	struct skinny_subchannel *activesub;
 	AST_LIST_HEAD(, skinny_subchannel) sub;
 	AST_LIST_HEAD(, skinny_subline) sublines;
@@ -1611,7 +1611,7 @@ static int skinny_indicate(struct ast_channel *ast, int ind, const void *data, s
 static int skinny_fixup(struct ast_channel *oldchan, struct ast_channel *newchan);
 static int skinny_senddigit_begin(struct ast_channel *ast, char digit);
 static int skinny_senddigit_end(struct ast_channel *ast, char digit, unsigned int duration);
-static void mwi_event_cb(const struct ast_event *event, void *userdata);
+static void mwi_event_cb(void *userdata, struct stasis_subscription *sub, struct stasis_topic *topic, struct stasis_message *msg);
 static int skinny_dialer_cb(const void *data);
 static int skinny_reload(void);
 
@@ -2261,7 +2261,7 @@ static int skinny_register(struct skinny_req *req, struct skinnysession *s)
 				manager_event(EVENT_FLAG_SYSTEM, "PeerStatus", "ChannelType: Skinny\r\nPeer: Skinny/%s@%s\r\nPeerStatus: Registered\r\n", l->name, d->name);
 				register_exten(l);
 				/* initialize MWI on line and device */
-				mwi_event_cb(0, l);
+				mwi_event_cb(l, NULL, NULL, NULL);
 				AST_LIST_TRAVERSE(&l->sublines, subline, list) {
 					ast_extension_state_add(subline->context, subline->exten, skinny_extensionstate_cb, subline->container);
 				}
@@ -3507,7 +3507,7 @@ static void update_connectedline(struct skinny_subchannel *sub, const void *data
 	send_callinfo(sub);
 }
 
-static void mwi_event_cb(const struct ast_event *event, void *userdata)
+static void mwi_event_cb(void *userdata, struct stasis_subscription *sub, struct stasis_topic *topic, struct stasis_message *msg)
 {
 	struct skinny_line *l = userdata;
 	struct skinny_device *d = l->device;
@@ -3518,8 +3518,9 @@ static void mwi_event_cb(const struct ast_event *event, void *userdata)
 		return;
 	}
 
-	if (event) {
-		l->newmsgs = ast_event_get_ie_uint(event, AST_EVENT_IE_NEWMSGS);
+	if (msg && stasis_mwi_state_message() == stasis_message_type(msg)) {
+		struct stasis_mwi_state *mwi_state = stasis_message_data(msg);
+		l->newmsgs = mwi_state->new_msgs;
 	}
 
 	if (l->newmsgs) {
@@ -8250,16 +8251,22 @@ static struct skinny_line *config_line(const char *lname, struct ast_variable *v
 
 	if (!ast_strlen_zero(l->mailbox)) {
 		char *cfg_mailbox, *cfg_context;
+		struct ast_str *uniqueid = ast_str_alloca(AST_MAX_MAILBOX_UNIQUEID);
+		struct stasis_topic *mailbox_specific_topic;
+
 		cfg_context = cfg_mailbox = ast_strdupa(l->mailbox);
 		ast_verb(3, "Setting mailbox '%s' on line %s\n", cfg_mailbox, l->name);
 		strsep(&cfg_context, "@");
-		if (ast_strlen_zero(cfg_context))
-			 cfg_context = "default";
-		l->mwi_event_sub = ast_event_subscribe(AST_EVENT_MWI, mwi_event_cb, "skinny MWI subsciption", l,
-			AST_EVENT_IE_MAILBOX, AST_EVENT_IE_PLTYPE_STR, cfg_mailbox,
-			AST_EVENT_IE_CONTEXT, AST_EVENT_IE_PLTYPE_STR, cfg_context,
-			AST_EVENT_IE_NEWMSGS, AST_EVENT_IE_PLTYPE_EXISTS,
-			AST_EVENT_IE_END);
+		if (ast_strlen_zero(cfg_context)) {
+			cfg_context = "default";
+		}
+
+		ast_str_set(&uniqueid, 0, "%s@%s", cfg_mailbox, cfg_context);
+
+		mailbox_specific_topic = stasis_mwi_topic(ast_str_buffer(uniqueid));
+		if (mailbox_specific_topic) {
+			l->mwi_event_sub = stasis_subscribe(mailbox_specific_topic, mwi_event_cb, l);
+		}
 	}
 
 	if (!ast_strlen_zero(vmexten) && ast_strlen_zero(l->vmexten)) {
@@ -8694,8 +8701,9 @@ static int unload_module(void)
 				}
 				ast_mutex_unlock(&sub->lock);
 			}
-			if (l->mwi_event_sub)
-				ast_event_unsubscribe(l->mwi_event_sub);
+			if (l->mwi_event_sub) {
+				l->mwi_event_sub = stasis_unsubscribe(l->mwi_event_sub);
+			}
 			ast_mutex_unlock(&l->lock);
 			manager_event(EVENT_FLAG_SYSTEM, "PeerStatus", "ChannelType: Skinny\r\nPeer: Skinny/%s@%s\r\nPeerStatus: Unregistered\r\n", l->name, d->name);
 			unregister_exten(l);
diff --git a/channels/chan_unistim.c b/channels/chan_unistim.c
index b4ec9e455..130549c01 100644
--- a/channels/chan_unistim.c
+++ b/channels/chan_unistim.c
@@ -5500,23 +5500,24 @@ static int unistim_sendtext(struct ast_channel *ast, const char *text)
 /*--- unistim_send_mwi_to_peer: Send message waiting indication ---*/
 static int unistim_send_mwi_to_peer(struct unistim_line *peer, unsigned int tick)
 {
-	struct ast_event *event;
 	int new;
 	char *mailbox, *context;
+	RAII_VAR(struct stasis_message *, msg, NULL, ao2_cleanup);
+	struct ast_str *uniqueid = ast_str_alloca(AST_MAX_MAILBOX_UNIQUEID);
 
 	context = mailbox = ast_strdupa(peer->mailbox);
 	strsep(&context, "@");
 	if (ast_strlen_zero(context)) {
 		context = "default";
 	}
-	event = ast_event_get_cached(AST_EVENT_MWI,
-		AST_EVENT_IE_MAILBOX, AST_EVENT_IE_PLTYPE_STR, mailbox,
-		AST_EVENT_IE_CONTEXT, AST_EVENT_IE_PLTYPE_STR, context,
-		AST_EVENT_IE_END);
 
-	if (event) {
-		new = ast_event_get_ie_uint(event, AST_EVENT_IE_NEWMSGS);
-		ast_event_destroy(event);
+	ast_str_set(&uniqueid, 0, "%s@%s", mailbox, context);
+
+	msg = stasis_cache_get(stasis_mwi_topic_cached(), stasis_mwi_state_message(), ast_str_buffer(uniqueid));
+
+	if (msg) {
+		struct stasis_mwi_state *mwi_state = stasis_message_data(msg);
+		new = mwi_state->new_msgs;
 	} else { /* Fall back on checking the mailbox directly */
 		new = ast_app_has_voicemail(peer->mailbox, "INBOX");
 	}
diff --git a/channels/sig_pri.c b/channels/sig_pri.c
index e01ceadd3..e3b9b3fb6 100644
--- a/channels/sig_pri.c
+++ b/channels/sig_pri.c
@@ -8752,23 +8752,30 @@ static void sig_pri_send_mwi_indication(struct sig_pri_span *pri, const char *vm
  *
  * \return Nothing
  */
-static void sig_pri_mwi_event_cb(const struct ast_event *event, void *userdata)
+static void sig_pri_mwi_event_cb(void *userdata, struct stasis_subscription *sub, struct stasis_topic *topic, struct stasis_message *msg)
 {
 	struct sig_pri_span *pri = userdata;
 	const char *mbox_context;
 	const char *mbox_number;
 	int num_messages;
 	int idx;
+	struct stasis_mwi_state *mwi_state;
 
-	mbox_number = ast_event_get_ie_str(event, AST_EVENT_IE_MAILBOX);
+	if (stasis_mwi_state_message() != stasis_message_type(msg)) {
+		return;
+	}
+
+	mwi_state = stasis_message_data(msg);
+
+	mbox_number = mwi_state->mailbox;
 	if (ast_strlen_zero(mbox_number)) {
 		return;
 	}
-	mbox_context = ast_event_get_ie_str(event, AST_EVENT_IE_CONTEXT);
+	mbox_context = mwi_state->context;
 	if (ast_strlen_zero(mbox_context)) {
 		return;
 	}
-	num_messages = ast_event_get_ie_uint(event, AST_EVENT_IE_NEWMSGS);
+	num_messages = mwi_state->new_msgs;
 
 	for (idx = 0; idx < ARRAY_LEN(pri->mbox); ++idx) {
 		if (!pri->mbox[idx].sub) {
@@ -8799,27 +8806,28 @@ static void sig_pri_mwi_event_cb(const struct ast_event *event, void *userdata)
 static void sig_pri_mwi_cache_update(struct sig_pri_span *pri)
 {
 	int idx;
-	int num_messages;
-	struct ast_event *event;
+	struct ast_str *uniqueid = ast_str_alloca(AST_MAX_MAILBOX_UNIQUEID);
+	struct stasis_mwi_state *mwi_state;
 
 	for (idx = 0; idx < ARRAY_LEN(pri->mbox); ++idx) {
+		RAII_VAR(struct stasis_message *, msg, NULL, ao2_cleanup);
 		if (!pri->mbox[idx].sub) {
 			/* Mailbox slot is empty */
 			continue;
 		}
 
-		event = ast_event_get_cached(AST_EVENT_MWI,
-			AST_EVENT_IE_MAILBOX, AST_EVENT_IE_PLTYPE_STR, pri->mbox[idx].number,
-			AST_EVENT_IE_CONTEXT, AST_EVENT_IE_PLTYPE_STR, pri->mbox[idx].context,
-			AST_EVENT_IE_END);
-		if (!event) {
+		ast_str_reset(uniqueid);
+		ast_str_set(&uniqueid, 0, "%s@%s", pri->mbox[idx].number, pri->mbox[idx].context);
+
+		msg = stasis_cache_get(stasis_mwi_topic_cached(), stasis_mwi_state_message(), ast_str_buffer(uniqueid));
+		if (!msg) {
 			/* No cached event for this mailbox. */
 			continue;
 		}
-		num_messages = ast_event_get_ie_uint(event, AST_EVENT_IE_NEWMSGS);
+
+		mwi_state = stasis_message_data(msg);
 		sig_pri_send_mwi_indication(pri, pri->mbox[idx].vm_number, pri->mbox[idx].number,
-			pri->mbox[idx].context, num_messages);
-		ast_event_destroy(event);
+			pri->mbox[idx].context, mwi_state->new_msgs);
 	}
 }
 #endif	/* defined(HAVE_PRI_MWI) */
@@ -8841,7 +8849,7 @@ void sig_pri_stop_pri(struct sig_pri_span *pri)
 #if defined(HAVE_PRI_MWI)
 	for (idx = 0; idx < ARRAY_LEN(pri->mbox); ++idx) {
 		if (pri->mbox[idx].sub) {
-			pri->mbox[idx].sub = ast_event_unsubscribe(pri->mbox[idx].sub);
+			pri->mbox[idx].sub = stasis_unsubscribe(pri->mbox[idx].sub);
 		}
 	}
 #endif	/* defined(HAVE_PRI_MWI) */
@@ -8905,13 +8913,14 @@ int sig_pri_start_pri(struct sig_pri_span *pri)
 	char *saveptr;
 	char *prev_vm_number;
 	struct ast_str *mwi_description = ast_str_alloca(64);
+	struct ast_str *uniqueid = ast_str_alloca(AST_MAX_MAILBOX_UNIQUEID);
 #endif	/* defined(HAVE_PRI_MWI) */
 
 #if defined(HAVE_PRI_MWI)
 	/* Prepare the mbox[] for use. */
 	for (i = 0; i < ARRAY_LEN(pri->mbox); ++i) {
 		if (pri->mbox[i].sub) {
-			pri->mbox[i].sub = ast_event_unsubscribe(pri->mbox[i].sub);
+			pri->mbox[i].sub = stasis_unsubscribe(pri->mbox[i].sub);
 		}
 	}
 #endif	/* defined(HAVE_PRI_MWI) */
@@ -8951,6 +8960,7 @@ int sig_pri_start_pri(struct sig_pri_span *pri)
 	for (i = 0; i < ARRAY_LEN(pri->mbox); ++i) {
 		char *mbox_number;
 		char *mbox_context;
+		struct stasis_topic *mailbox_specific_topic;
 
 		mbox_number = strsep(&saveptr, ",");
 		if (!mbox_number) {
@@ -8976,13 +8986,17 @@ int sig_pri_start_pri(struct sig_pri_span *pri)
 		/* Fill the mbox[] element. */
 		pri->mbox[i].number = mbox_number;
 		pri->mbox[i].context = mbox_context;
+
+		ast_str_reset(uniqueid);
+		ast_str_set(&uniqueid, 0, "%s@%s", mbox_number, mbox_context);
+
 		ast_str_set(&mwi_description, -1, "%s span %d[%d] MWI mailbox %s@%s",
 			sig_pri_cc_type_name, pri->span, i, mbox_number, mbox_context);
-		pri->mbox[i].sub = ast_event_subscribe(AST_EVENT_MWI, sig_pri_mwi_event_cb,
-			ast_str_buffer(mwi_description), pri,
-			AST_EVENT_IE_MAILBOX, AST_EVENT_IE_PLTYPE_STR, mbox_number,
-			AST_EVENT_IE_CONTEXT, AST_EVENT_IE_PLTYPE_STR, mbox_context,
-			AST_EVENT_IE_END);
+
+		mailbox_specific_topic = stasis_mwi_topic(ast_str_buffer(uniqueid));
+		if (mailbox_specific_topic) {
+			pri->mbox[i].sub = stasis_subscribe(mailbox_specific_topic, sig_pri_mwi_event_cb, pri);
+		}
 		if (!pri->mbox[i].sub) {
 			ast_log(LOG_ERROR, "%s span %d could not subscribe to MWI events for %s@%s.",
 				sig_pri_cc_type_name, pri->span, mbox_number, mbox_context);
diff --git a/channels/sig_pri.h b/channels/sig_pri.h
index 4de9077e7..db052862d 100644
--- a/channels/sig_pri.h
+++ b/channels/sig_pri.h
@@ -405,7 +405,7 @@ struct sig_pri_mbox {
 	 * \brief MWI mailbox event subscription.
 	 * \note NULL if mailbox not configured.
 	 */
-	struct ast_event_sub *sub;
+	struct stasis_subscription *sub;
 	/*! \brief Mailbox number */
 	const char *number;
 	/*! \brief Mailbox context. */
diff --git a/channels/sip/include/sip.h b/channels/sip/include/sip.h
index e5177bd6a..6eb2f29a5 100644
--- a/channels/sip/include/sip.h
+++ b/channels/sip/include/sip.h
@@ -1262,7 +1262,7 @@ struct sip_pkt {
  */
 struct sip_mailbox {
 	/*! Associated MWI subscription */
-	struct ast_event_sub *event_sub;
+	struct stasis_subscription *event_sub;
 	AST_LIST_ENTRY(sip_mailbox) entry;
 	unsigned int delme:1;
 	char *context;