main/asterisk: update ASTERISK-19106 patch

It's now the patch that actually got committed.

2 files changed, 173 insertions, 118 deletions

diff --git a/main/asterisk/APKBUILD b/main/asterisk/APKBUILD
index b7e7486e5..309c26e5b 100644
--- a/main/asterisk/APKBUILD
+++ b/main/asterisk/APKBUILD
@@ -2,7 +2,7 @@
 # Maintainer: Timo Teras <timo.teras@iki.fi>
 pkgname=asterisk
 pkgver=10.1.0
-pkgrel=0
+pkgrel=1
 pkgdesc="Asterisk: A Module Open Source PBX System"
 url="http://www.asterisk.org/"
 arch="all"
@@ -167,7 +167,7 @@ b794636266cc573f0dda730fba634567  900-tryinclude.patch
 da5a3c500192dee4275aae5235d25f97  ASTERISK-18976.patch
 1ddadef41aa7120e168738b6f3ed8917  ASTERISK-18977.patch
 bc6713f5434e07b79d3afdd155461d72  ASTERISK-18995.patch
-8190437436de46b3a5a607f56f5af539  ASTERISK-19106.patch
+2581cf79297ebf4ce4a7145f07512c7e  ASTERISK-19106.patch
 a22bb1d513d026564cb40ec213b1ae7f  ASTERISK-19109.patch
 74cd25a5638a94ef51e9f4ede2fd28f2  asterisk.initd
 ed31d7ba37bcf8b0346dcf8593c395f0  asterisk.confd
diff --git a/main/asterisk/ASTERISK-19106.patch b/main/asterisk/ASTERISK-19106.patch
index 93e9d2d89..d66c4744d 100644
--- a/main/asterisk/ASTERISK-19106.patch
+++ b/main/asterisk/ASTERISK-19106.patch
@@ -1,20 +1,62 @@
-Index: channels/chan_sip.c
-===================================================================
---- a/channels/chan_sip.c	(revision 352352)
-+++ b/channels/chan_sip.c	(working copy)
-@@ -2883,6 +2883,11 @@
+commit f987e47193c1ce64466663134e5e311742d022d2
+Author: twilson <twilson@f38db490-d61c-443f-a65b-d21fe96a405b>
+Date:   Mon Jan 30 23:58:51 2012 +0000
+
+    Re-link peers by IP when dnsmgr changes the IP
+    
+    Asterisk's dnsmgr currently takes a pointer to an ast_sockaddr and updates it
+    anytime an address resolves to something different. There are a couple of
+    issues with this. First, the ast_sockaddr is usually the address of an
+    ast_sockaddr inside a refcounted struct and we never bump the refcount of those
+    structs when using dnsmgr. This makes it possible that a refresh could happen
+    after the destructor for that object is called (despite ast_dnsmgr_release
+    being called in that destructor). Second, the module using dnsmgr cannot be
+    aware of an address changing without polling for it in the code. If an action
+    needs to be taken on address update (like re-linking a SIP peer in the
+    peers_by_ip table), then polling for this change negates many of the benefits
+    of having dnsmgr in the first place.
+    
+    This patch adds a function to the dnsmgr API that calls an update callback
+    instead of blindly updating the address itself. It also moves calls to
+    ast_dnsmgr_release outside of the destructor functions and into cleanup
+    functions that are called when we no longer need the objects and increments the
+    refcount of the objects using dnsmgr since those objects are stored on the
+    ast_dnsmgr_entry struct. A helper function for returning the proper default SIP
+    port (non-tls vs tls) is also added and used.
+    
+    This patch also incorporates changes from a patch posted by Timo Teräs to
+    ASTERISK-19106 for related dnsmgr issues.
+    
+    (closes issue ASTERISK-19106)
+    
+    Review: https://reviewboard.asterisk.org/r/1691/
+    ........
+    
+    Merged revisions 353371 from http://svn.asterisk.org/svn/asterisk/branches/1.8
+    ........
+    
+    Merged revisions 353397 from http://svn.asterisk.org/svn/asterisk/branches/10
+    
+    
+    git-svn-id: http://svn.digium.com/svn/asterisk/trunk@353418 f38db490-d61c-443f-a65b-d21fe96a405b
+
+diff --git a/channels/chan_sip.c b/channels/chan_sip.c
+index e1dfaea..698894f 100644
+--- a/channels/chan_sip.c
++++ b/channels/chan_sip.c
+@@ -2897,6 +2897,11 @@ static int match_and_cleanup_peer_sched(void *peerobj, void *arg, int flags)
  
  	if (which == SIP_PEERS_ALL || peer->the_mark) {
  		peer_sched_cleanup(peer);
 +		if (peer->dnsmgr) {
 +			ast_dnsmgr_release(peer->dnsmgr);
-+			ao2_t_ref(peer, -1, "Release peer from dnsmgr");
 +			peer->dnsmgr = NULL;
++			sip_unref_peer(peer, "Release peer from dnsmgr");
 +		}
  		return CMP_MATCH;
  	}
  	return 0;
-@@ -4661,8 +4666,6 @@
+@@ -4681,8 +4686,6 @@ static void sip_destroy_peer(struct sip_peer *peer)
  		ao2_t_ref(peer->auth, -1, "Removing peer authentication");
  		peer->auth = NULL;
  	}
@@ -23,7 +65,7 @@ Index: channels/chan_sip.c
  
  	if (peer->socket.tcptls_session) {
  		ao2_ref(peer->socket.tcptls_session, -1);
-@@ -5401,6 +5404,12 @@
+@@ -5423,6 +5426,12 @@ static int create_addr_from_peer(struct sip_pvt *dialog, struct sip_peer *peer)
  	return 0;
  }
  
@@ -36,7 +78,7 @@ Index: channels/chan_sip.c
  /*! \brief create address structure from device name
   *      Or, if peer not found, find it in the global DNS
   *      returns TRUE (-1) on failure, FALSE on success */
-@@ -5503,9 +5512,7 @@
+@@ -5525,9 +5534,7 @@ static int create_addr(struct sip_pvt *dialog, const char *opeer, struct ast_soc
  	}
  
  	if (!ast_sockaddr_port(&dialog->sa)) {
@@ -47,7 +89,7 @@ Index: channels/chan_sip.c
  	}
  	ast_sockaddr_copy(&dialog->recv, &dialog->sa);
  	return 0;
-@@ -5725,7 +5732,6 @@
+@@ -5747,7 +5754,6 @@ static void sip_registry_destroy(struct sip_registry *reg)
  
  	ast_string_field_free_memory(reg);
  	ast_atomic_fetchadd_int(&regobjs, -1);
@@ -55,7 +97,7 @@ Index: channels/chan_sip.c
  	ast_free(reg);
  }
  
-@@ -5739,7 +5745,6 @@
+@@ -5761,7 +5767,6 @@ static void sip_subscribe_mwi_destroy(struct sip_subscription_mwi *mwi)
  	
  	AST_SCHED_DEL(sched, mwi->resub);
  	ast_string_field_free_memory(mwi);
@@ -63,13 +105,14 @@ Index: channels/chan_sip.c
  	ast_free(mwi);
  }
  
-@@ -12565,6 +12570,67 @@
+@@ -12721,6 +12726,72 @@ static int sip_subscribe_mwi_do(const void *data)
  	return 0;
  }
  
 +static void on_dns_update_registry(struct ast_sockaddr *old, struct ast_sockaddr *new, void *data)
 +{
 +	struct sip_registry *reg = data;
++	const char *old_str;
 +
 +	/* This shouldn't happen, but just in case */
 +	if (ast_sockaddr_isnull(new)) {
@@ -80,14 +123,17 @@ Index: channels/chan_sip.c
 +	if (!ast_sockaddr_port(new)) {
 +		ast_sockaddr_set_port(new, reg->portno);
 +	}
-+	
-+	ast_debug(1, "Changing registry %s from %s to %s\n", S_OR(reg->peername, reg->hostname), ast_sockaddr_stringify(old), ast_sockaddr_stringify(new));
++
++	old_str = ast_strdupa(ast_sockaddr_stringify(old));
++
++	ast_debug(1, "Changing registry %s from %s to %s\n", S_OR(reg->peername, reg->hostname), old_str, ast_sockaddr_stringify(new));
 +	ast_sockaddr_copy(&reg->us, new);
 +}
 +
 +static void on_dns_update_peer(struct ast_sockaddr *old, struct ast_sockaddr *new, void *data)
 +{
 +	struct sip_peer *peer = data;
++	const char *old_str;
 +
 +	/* This shouldn't happen, but just in case */
 +	if (ast_sockaddr_isnull(new)) {
@@ -95,7 +141,6 @@ Index: channels/chan_sip.c
 +		return;
 +	}
 +
-+	ao2_ref(peer, +1);
 +	if (!ast_sockaddr_isnull(&peer->addr)) {
 +		ao2_unlink(peers_by_ip, peer);
 +	}
@@ -104,19 +149,20 @@ Index: channels/chan_sip.c
 +		ast_sockaddr_set_port(new, default_sip_port(peer->socket.type));
 +	}
 +
-+	ast_debug(1, "Changing peer %s address from %s to %s\n", peer->name, ast_sockaddr_stringify(old), ast_sockaddr_stringify(new));
++	old_str = ast_strdupa(ast_sockaddr_stringify(old));
++	ast_debug(1, "Changing peer %s address from %s to %s\n", peer->name, old_str, ast_sockaddr_stringify(new));
 +
 +	ao2_lock(peer);
 +	ast_sockaddr_copy(&peer->addr, new);
 +	ao2_unlock(peer);
 +
 +	ao2_link(peers_by_ip, peer);
-+	ao2_ref(peer, -1);
 +}
 +
 +static void on_dns_update_mwi(struct ast_sockaddr *old, struct ast_sockaddr *new, void *data)
 +{
 +	struct sip_subscription_mwi *mwi = data;
++	const char *old_str;
 +
 +	/* This shouldn't happen, but just in case */
 +	if (ast_sockaddr_isnull(new)) {
@@ -124,27 +170,28 @@ Index: channels/chan_sip.c
 +		return;
 +	}
 +
-+	ast_debug(1, "Changing mwi %s from %s to %s\n", mwi->hostname, ast_sockaddr_stringify(old), ast_sockaddr_stringify(new));
++	old_str = ast_strdupa(ast_sockaddr_stringify(old));
++	ast_debug(1, "Changing mwi %s from %s to %s\n", mwi->hostname, old_str, ast_sockaddr_stringify(new));
 +	ast_sockaddr_copy(&mwi->us, new);
 +}
 +
  /*! \brief Actually setup an MWI subscription or resubscribe */
  static int __sip_subscribe_mwi_do(struct sip_subscription_mwi *mwi)
  {
-@@ -12574,7 +12640,11 @@
+@@ -12730,7 +12801,11 @@ static int __sip_subscribe_mwi_do(struct sip_subscription_mwi *mwi)
  		snprintf(transport, sizeof(transport), "_%s._%s", get_srv_service(mwi->transport), get_srv_protocol(mwi->transport));
  
  		mwi->us.ss.ss_family = get_address_family_filter(&bindaddr); /* Filter address family */
 -		ast_dnsmgr_lookup(mwi->hostname, &mwi->us, &mwi->dnsmgr, sip_cfg.srvlookup ? transport : NULL);
-+		ASTOBJ_REF(mwi); /* Add aref for storing the mwi on the dnsmgr for updates */
-+		ast_dnsmgr_lookup(mwi->hostname, &mwi->us, &mwi->dnsmgr, sip_cfg.srvlookup ? transport : NULL, on_dns_update_mwi, mwi);
++		ASTOBJ_REF(mwi); /* Add a ref for storing the mwi on the dnsmgr for updates */
++		ast_dnsmgr_lookup_cb(mwi->hostname, &mwi->us, &mwi->dnsmgr, sip_cfg.srvlookup ? transport : NULL, on_dns_update_mwi, mwi);
 +		if (!mwi->dnsmgr) {
 +			ASTOBJ_UNREF(mwi, sip_subscribe_mwi_destroy); /* dnsmgr disabled, remove reference */
 +		}
  	}
  
  	/* If we already have a subscription up simply send a resubscription */
-@@ -13255,17 +13325,8 @@
+@@ -13411,17 +13486,8 @@ static int sip_reg_timeout(const void *data)
  	}
  
  	if (r->dnsmgr) {
@@ -162,46 +209,43 @@ Index: channels/chan_sip.c
  	}
  
  	/* If the initial tranmission failed, we may not have an existing dialog,
-@@ -13348,10 +13409,16 @@
- 		peer = sip_find_peer(r->hostname, NULL, TRUE, FINDPEERS, FALSE, 0);
- 		snprintf(transport, sizeof(transport), "_%s._%s",get_srv_service(r->transport), get_srv_protocol(r->transport)); /* have to use static sip_get_transport function */
- 		r->us.ss.ss_family = get_address_family_filter(&bindaddr); /* Filter address family */
--		ast_dnsmgr_lookup(peer ? peer->tohost : r->hostname, &r->us, &r->dnsmgr, sip_cfg.srvlookup ? transport : NULL);
-+		registry_addref(r, "add reg ref for dnsmgr");
-+		ast_dnsmgr_lookup(peer ? peer->tohost : r->hostname, &r->us, &r->dnsmgr, sip_cfg.srvlookup ? transport : NULL, on_dns_update_registry, r);
+@@ -13510,7 +13576,12 @@ static int transmit_register(struct sip_registry *r, int sipmethod, const char *
+ 		 * or peer NULL. Since we're only concerned with its existence, we're not going to
+ 		 * bother getting a ref to the proxy*/
+ 		if (!obproxy_get(r->call, peer)) {
+-			ast_dnsmgr_lookup(peer ? peer->tohost : r->hostname, &r->us, &r->dnsmgr, sip_cfg.srvlookup ? transport : NULL);
++			registry_addref(r, "add reg ref for dnsmgr");
++			ast_dnsmgr_lookup_cb(peer ? peer->tohost : r->hostname, &r->us, &r->dnsmgr, sip_cfg.srvlookup ? transport : NULL, on_dns_update_registry, r);
++			if (!r->dnsmgr) {
++				/*dnsmgr refresh disabled, no reference added! */
++				registry_unref(r, "remove reg ref, dnsmgr disabled");
++			}
+ 		}
  		if (peer) {
  			peer = sip_unref_peer(peer, "removing peer ref for dnsmgr_lookup");
- 		}
-+		if (!r->dnsmgr) {
-+			/* dnsmgr refresh disabled, no reference added! */
-+			registry_unref(r, "remove reg ref, dnsmgr disabled");
-+		}
-+
- 	}
- 
- 	if (r->call) {	/* We have a registration */
-@@ -13380,18 +13447,21 @@
+@@ -13543,18 +13614,21 @@ static int transmit_register(struct sip_registry *r, int sipmethod, const char *
  		}
  
  		/* Use port number specified if no SRV record was found */
 -		if (!ast_sockaddr_port(&r->us) && r->portno) {
 -			ast_sockaddr_set_port(&r->us, r->portno);
 -		}
-+		if (!ast_sockaddr_isnull(&r->us)) {
-+			if (!ast_sockaddr_port(&r->us) && r->portno) {
-+				ast_sockaddr_set_port(&r->us, r->portno);
-+			}
-+			/* It is possible that DNS was unavailable at the time the peer was created.
-+			 * Here, if we've update the address in the registry via manually calling
-+			 * ast_dnsmgr_lookup() above, then we call the same function that dnsmgr would
-+			 * call if it was updating a peer's address */
- 
+-
 -		/* It is possible that DNS is unavailable at the time the peer is created. Here, if
 -		 * we've updated the address in the registry, we copy it to the peer so that
 -		 * create_addr() can copy it to the dialog via create_addr_from_peer */
 -		if ((peer = sip_find_peer(r->hostname, NULL, TRUE, FINDPEERS, FALSE, 0))) {
 -			if (ast_sockaddr_isnull(&peer->addr) && !(ast_sockaddr_isnull(&r->us))) {
 -				ast_sockaddr_copy(&peer->addr, &r->us);
++		if (!ast_sockaddr_isnull(&r->us)) {
++			if (!ast_sockaddr_port(&r->us) && r->portno) {
++				ast_sockaddr_set_port(&r->us, r->portno);
++			}
++
++			/* It is possible that DNS was unavailable at the time the peer was created.
++			 * Here, if we've updated the address in the registry via manually calling
++			 * ast_dnsmgr_lookup_cb() above, then we call the same function that dnsmgr would
++			 * call if it was updating a peer's address */
 +			if ((peer = sip_find_peer(S_OR(r->peername, r->hostname), NULL, TRUE, FINDPEERS, FALSE, 0))) {
 +				if (ast_sockaddr_cmp(&peer->addr, &r->us)) {
 +					on_dns_update_peer(&peer->addr, &r->us, peer);
@@ -212,7 +256,7 @@ Index: channels/chan_sip.c
  		}
  
  		/* Find address to hostname */
-@@ -14243,9 +14313,7 @@
+@@ -14392,9 +14466,7 @@ static enum parse_register_result parse_register_contact(struct sip_pvt *pvt, st
  		peer->portinuri = ast_sockaddr_port(&testsa) ? TRUE : FALSE;
  
  		if (!ast_sockaddr_port(&testsa)) {
@@ -223,93 +267,68 @@ Index: channels/chan_sip.c
  		}
  
  		ast_sockaddr_copy(&peer->addr, &testsa);
-@@ -28327,11 +28395,16 @@
+@@ -28679,11 +28751,17 @@ static struct sip_peer *build_peer(const char *name, struct ast_variable *v, str
  		snprintf(transport, sizeof(transport), "_%s._%s", get_srv_service(peer->socket.type), get_srv_protocol(peer->socket.type));
  
  		peer->addr.ss.ss_family = get_address_family_filter(&bindaddr); /* Filter address family */
 -		if (ast_dnsmgr_lookup(_srvlookup, &peer->addr, &peer->dnsmgr, sip_cfg.srvlookup && !peer->portinuri ? transport : NULL)) {
-+		ao2_t_ref(peer, +1, "Store peer on dnsmgr"); /* Ref for storing peer (and peer->addr) on the dnsmgr for the callback */
-+		if (ast_dnsmgr_lookup(_srvlookup, &peer->addr, &peer->dnsmgr, sip_cfg.srvlookup && !peer->portinuri ? transport : NULL, on_dns_update_peer, peer)) {
++		if (ast_dnsmgr_lookup_cb(_srvlookup, &peer->addr, &peer->dnsmgr, sip_cfg.srvlookup && !peer->portinuri ? transport : NULL,
++					on_dns_update_peer, sip_ref_peer(peer, "Store peer on dnsmgr"))) {
  			ast_log(LOG_ERROR, "srvlookup failed for host: %s, on peer %s, removing peer\n", _srvlookup, peer->name);
++			sip_unref_peer(peer, "dnsmgr lookup failed, getting rid of peer dnsmgr ref");
  			sip_unref_peer(peer, "getting rid of a peer pointer");
  			return NULL;
  		}
 +		if (!peer->dnsmgr) {
 +			/* dnsmgr refresh disabeld, release reference */
-+			ao2_t_ref(peer, -1, "dnsmgr disabled, unref peer");
++			sip_unref_peer(peer, "dnsmgr disabled, unref peer");
 +		}
  
  		ast_string_field_set(peer, tohost, srvlookup);
  
-@@ -28549,6 +28622,11 @@
+@@ -28817,7 +28895,7 @@ static void cleanup_all_regs(void)
+ 		/* First, destroy all outstanding registry calls */
+ 		/* This is needed, since otherwise active registry entries will not be destroyed */
+ 		ASTOBJ_CONTAINER_TRAVERSE(&regl, 1, do {  /* regl is locked */
+-				ASTOBJ_RDLOCK(iterator); /* now regl is locked, and the object is also locked */
++				ASTOBJ_WRLOCK(iterator); /* now regl is locked, and the object is also locked */
+ 				if (iterator->call) {
+ 					ast_debug(3, "Destroying active SIP dialog for registry %s@%s\n", iterator->username, iterator->hostname);
+ 					/* This will also remove references to the registry */
+@@ -28830,6 +28908,11 @@ static void cleanup_all_regs(void)
  				if (iterator->timeout > -1) {
  					AST_SCHED_DEL_UNREF(sched, iterator->timeout, registry_unref(iterator, "reg ptr unref from reload config"));
  				}
 +				if (iterator->dnsmgr) {
 +					ast_dnsmgr_release(iterator->dnsmgr);
-+					registry_unref(iterator, "reg ptr unref from dnsmgr");
 +					iterator->dnsmgr = NULL;
++					registry_unref(iterator, "reg ptr unref from dnsmgr");
 +				}
  				ASTOBJ_UNLOCK(iterator);
  		} while(0));
- 
-@@ -31105,8 +31183,29 @@
- 		ast_free(default_tls_cfg.capath);
- 	}
- 
-+	ASTOBJ_CONTAINER_TRAVERSE(&regl, 1, do {  /* regl is locked */
-+			ASTOBJ_RDLOCK(iterator); /* now regl is locked, and the object is also locked */
-+			if (iterator->dnsmgr) {
-+				ast_dnsmgr_release(iterator->dnsmgr);
-+				registry_unref(iterator, "reg ptr unref from dnsmgr");
-+				iterator->dnsmgr = NULL;
-+			}
-+			ASTOBJ_UNLOCK(iterator);
-+	} while(0));
-+
+ }
+@@ -31496,6 +31579,16 @@ static int unload_module(void)
+ 	cleanup_all_regs();
  	ASTOBJ_CONTAINER_DESTROYALL(&regl, sip_registry_destroy);
  	ASTOBJ_CONTAINER_DESTROY(&regl);
 +
 +	ASTOBJ_CONTAINER_TRAVERSE(&submwil, 1, do {
-+		ASTOBJ_RDLOCK(iterator);
++		ASTOBJ_WRLOCK(iterator);
 +		if (iterator->dnsmgr) {
 +			ast_dnsmgr_release(iterator->dnsmgr);
-+			ASTOBJ_UNREF(iterator, sip_subscribe_mwi_destroy);
 +			iterator->dnsmgr = NULL;
++			ASTOBJ_UNREF(iterator, sip_subscribe_mwi_destroy);
 +		}
 +		ASTOBJ_UNLOCK(iterator);
 +	} while(0));
-+
  	ASTOBJ_CONTAINER_DESTROYALL(&submwil, sip_subscribe_mwi_destroy);
  	ASTOBJ_CONTAINER_DESTROY(&submwil);
  
-Index: channels/chan_iax2.c
-===================================================================
---- a/channels/chan_iax2.c	(revision 352352)
-+++ b/channels/chan_iax2.c	(working copy)
-@@ -8587,7 +8587,7 @@
- 		return -1;
- 
- 	reg->addr.ss.ss_family = AF_INET;
--	if (ast_dnsmgr_lookup(hostname, &reg->addr, &reg->dnsmgr, srvlookup ? "_iax._udp" : NULL) < 0) {
-+	if (ast_dnsmgr_lookup(hostname, &reg->addr, &reg->dnsmgr, srvlookup ? "_iax._udp" : NULL, NULL, NULL) < 0) {
- 		ast_free(reg);
- 		return -1;
- 	}
-@@ -12595,7 +12595,7 @@
- 					/* Non-dynamic.  Make sure we become that way if we're not */
- 					AST_SCHED_DEL(sched, peer->expire);
- 					ast_clear_flag64(peer, IAX_DYNAMIC);
--					if (ast_dnsmgr_lookup(v->value, &peer->addr, &peer->dnsmgr, srvlookup ? "_iax._udp" : NULL))
-+					if (ast_dnsmgr_lookup(v->value, &peer->addr, &peer->dnsmgr, srvlookup ? "_iax._udp" : NULL, NULL, NULL))
- 						return peer_unref(peer);
- 					if (!ast_sockaddr_port(&peer->addr)) {
- 						ast_sockaddr_set_port(&peer->addr, IAX_DEFAULT_PORTNO);
-Index: include/asterisk/dnsmgr.h
-===================================================================
---- a/include/asterisk/dnsmgr.h	(revision 352352)
-+++ b/include/asterisk/dnsmgr.h	(working copy)
-@@ -37,6 +37,8 @@
+diff --git a/include/asterisk/dnsmgr.h b/include/asterisk/dnsmgr.h
+index b62c2a1..07d6268 100644
+--- a/include/asterisk/dnsmgr.h
++++ b/include/asterisk/dnsmgr.h
+@@ -37,6 +37,8 @@ extern "C" {
   */
  struct ast_dnsmgr_entry;
  
@@ -318,20 +337,43 @@ Index: include/asterisk/dnsmgr.h
  /*!
   * \brief Allocate a new DNS manager entry
   *
-@@ -102,7 +104,7 @@
-  * \retval non-zero failure
-  * \version 1.6.1 result changed from struct in_addr to struct aockaddr_in to store port number
-  */
--int ast_dnsmgr_lookup(const char *name, struct ast_sockaddr *result, struct ast_dnsmgr_entry **dnsmgr, const char *service);
-+int ast_dnsmgr_lookup(const char *name, struct ast_sockaddr *result, struct ast_dnsmgr_entry **dnsmgr, const char *service, dns_update_func func, void *data);
+@@ -105,6 +107,31 @@ void ast_dnsmgr_release(struct ast_dnsmgr_entry *entry);
+ int ast_dnsmgr_lookup(const char *name, struct ast_sockaddr *result, struct ast_dnsmgr_entry **dnsmgr, const char *service);
  
  /*!
++ * \brief Allocate and initialize a DNS manager entry, with update callback
++ *
++ * \param name the hostname
++ * \param result The addr which is intended to be updated in the update callback when DNS manager calls it on refresh.
++ * The address family is used as an input parameter to filter the returned addresses.
++ * If it is 0, both IPv4 and IPv6 addresses can be returned.
++ * \param dnsmgr Where to store the allocate DNS manager entry
++ * \param service
++ * \param func The update callback function
++ * The update callback will be called when DNS manager detects that an IP address has been changed.
++ * Instead of updating the addr itself, DNS manager will call this callback function with the old
++ * and new addresses. It is the responsibility of the callback to perform any updates
++ * \param data A pointer to data that will be passed through to the callback function
++ *
++ * \note
++ * This function allocates a new DNS manager entry object, and fills it with
++ * the provided hostname and IP address.  This function _does_ force an initial
++ * lookup, so it may block for some period of time.
++ *
++ * \retval 0 success
++ * \retval non-zero failure
++ */
++int ast_dnsmgr_lookup_cb(const char *name, struct ast_sockaddr *result, struct ast_dnsmgr_entry **dnsmgr, const char *service, dns_update_func func, void *data);
++
++/*!
   * \brief Force a refresh of a dnsmgr entry
-Index: main/dnsmgr.c
-===================================================================
---- a/main/dnsmgr.c	(revision 352352)
-+++ b/main/dnsmgr.c	(working copy)
-@@ -58,6 +58,10 @@
+  *
+  * \retval non-zero if the result is different than the previous result
+diff --git a/main/dnsmgr.c b/main/dnsmgr.c
+index d11cd99..7cdcd0c 100644
+--- a/main/dnsmgr.c
++++ b/main/dnsmgr.c
+@@ -58,6 +58,10 @@ struct ast_dnsmgr_entry {
  	unsigned int family;
  	/*! Set to 1 if the entry changes */
  	unsigned int changed:1;
@@ -342,17 +384,17 @@ Index: main/dnsmgr.c
  	ast_mutex_t lock;
  	AST_RWLIST_ENTRY(ast_dnsmgr_entry) list;
  	/*! just 1 here, but we use calloc to allocate the correct size */
-@@ -129,7 +133,7 @@
+@@ -130,7 +134,7 @@ void ast_dnsmgr_release(struct ast_dnsmgr_entry *entry)
  	ast_free(entry);
  }
  
 -int ast_dnsmgr_lookup(const char *name, struct ast_sockaddr *result, struct ast_dnsmgr_entry **dnsmgr, const char *service)
-+int ast_dnsmgr_lookup(const char *name, struct ast_sockaddr *result, struct ast_dnsmgr_entry **dnsmgr, const char *service, dns_update_func func, void *data)
++static int internal_dnsmgr_lookup(const char *name, struct ast_sockaddr *result, struct ast_dnsmgr_entry **dnsmgr, const char *service, dns_update_func func, void *data)
  {
  	unsigned int family;
  
-@@ -164,6 +168,8 @@
- 	
+@@ -165,9 +169,21 @@ int ast_dnsmgr_lookup(const char *name, struct ast_sockaddr *result, struct ast_
+ 
  	ast_verb(3, "adding dns manager for '%s'\n", name);
  	*dnsmgr = ast_dnsmgr_get_family(name, result, service, family);
 +	(*dnsmgr)->update_func = func;
@@ -360,7 +402,20 @@ Index: main/dnsmgr.c
  	return !*dnsmgr;
  }
  
-@@ -186,16 +192,19 @@
++int ast_dnsmgr_lookup(const char *name, struct ast_sockaddr *result, struct ast_dnsmgr_entry **dnsmgr, const char *service)
++{
++	return internal_dnsmgr_lookup(name, result, dnsmgr, service, NULL, NULL);
++}
++
++int ast_dnsmgr_lookup_cb(const char *name, struct ast_sockaddr *result, struct ast_dnsmgr_entry **dnsmgr, const char *service, dns_update_func func, void *data)
++{
++	return internal_dnsmgr_lookup(name, result, dnsmgr, service, func, data);
++}
++
+ /*
+  * Refresh a dnsmgr entry
+  */
+@@ -187,16 +203,19 @@ static int dnsmgr_refresh(struct ast_dnsmgr_entry *entry, int verbose)
  		if (!ast_sockaddr_port(&tmp)) {
  			ast_sockaddr_set_port(&tmp, ast_sockaddr_port(entry->result));
  		}