Updates all usages of ast_tcptls_session_instance to be managed by reference counts so that they only get destroyed when all threads are done using

them, and memory does not get free'd causing strange issues with SIP. 

This code was originally written by russellb in the team/group/issue_11972/ branch.


git-svn-id: http://svn.digium.com/svn/asterisk/trunk@123546 f38db490-d61c-443f-a65b-d21fe96a405b

1 files changed, 65 insertions, 50 deletions

diff --git a/channels/chan_sip.c b/channels/chan_sip.c
index 0c4a6e32a..d6a1ec961 100644
--- a/channels/chan_sip.c
+++ b/channels/chan_sip.c
@@ -798,7 +798,6 @@ enum sip_transport {
 
 /*!< The SIP socket definition */
 struct sip_socket {
-	ast_mutex_t *lock;
 	enum sip_transport type;
 	int fd;
 	uint16_t port;
@@ -844,6 +843,7 @@ struct sip_request {
 	char *header[SIP_MAX_HEADERS];
 	char *line[SIP_MAX_LINES];
 	struct ast_str *data;	
+	/* XXX Do we need to unref socket.ser when the request goes away? */
 	struct sip_socket socket;	/*!< The socket used for this request */
 };
 
@@ -2291,14 +2291,6 @@ static struct ast_rtp_protocol sip_rtp = {
 
 static void *_sip_tcp_helper_thread(struct sip_pvt *pvt, struct ast_tcptls_session_instance *ser);
 
-static void *sip_tcp_helper_thread(void *data)
-{
-	struct sip_pvt *pvt = data;
-	struct ast_tcptls_session_instance *ser = pvt->socket.ser;
-
-	return _sip_tcp_helper_thread(pvt, ser);
-}
-
 static void *sip_tcp_worker_fn(void *data)
 {
 	struct ast_tcptls_session_instance *ser = data;
@@ -2312,7 +2304,7 @@ static void *_sip_tcp_helper_thread(struct sip_pvt *pvt, struct ast_tcptls_sessi
 	int res, cl;
 	struct sip_request req = { 0, } , reqcpy = { 0, };
 	struct sip_threadinfo *me;
-	char buf[1024];
+	char buf[1024] = "";
 
 	me = ast_calloc(1, sizeof(*me));
 
@@ -2330,12 +2322,6 @@ static void *_sip_tcp_helper_thread(struct sip_pvt *pvt, struct ast_tcptls_sessi
 	AST_LIST_INSERT_TAIL(&threadl, me, list);
 	AST_LIST_UNLOCK(&threadl);
 
-	req.socket.lock = ast_calloc(1, sizeof(*req.socket.lock));
-
-	if (!req.socket.lock)
-		goto cleanup;
-
-	ast_mutex_init(req.socket.lock);
 	if (!(req.data = ast_str_create(SIP_MIN_PACKET)))
 		goto cleanup;
 	if (!(reqcpy.data = ast_str_create(SIP_MIN_PACKET)))
@@ -2364,14 +2350,12 @@ static void *_sip_tcp_helper_thread(struct sip_pvt *pvt, struct ast_tcptls_sessi
 
 		/* Read in headers one line at a time */
 		while (req.len < 4 || strncmp((char *)&req.data->str + req.len - 4, "\r\n\r\n", 4)) {
-			if (req.socket.lock) 
-				ast_mutex_lock(req.socket.lock);
+			ast_mutex_lock(&ser->lock);
 			if (!fgets(buf, sizeof(buf), ser->f)) {
-				ast_mutex_unlock(req.socket.lock);
+				ast_mutex_unlock(&ser->lock);
 				goto cleanup;
 			}
-			if (req.socket.lock) 
-				ast_mutex_unlock(req.socket.lock);
+			ast_mutex_unlock(&ser->lock);
 			if (me->stop) 
 				 goto cleanup;
 			ast_str_append(&req.data, 0, "%s", buf);
@@ -2381,12 +2365,12 @@ static void *_sip_tcp_helper_thread(struct sip_pvt *pvt, struct ast_tcptls_sessi
 		parse_request(&reqcpy);
 		if (sscanf(get_header(&reqcpy, "Content-Length"), "%d", &cl)) {
 			while (cl > 0) {
-				if (req.socket.lock) 
-					ast_mutex_lock(req.socket.lock);
-				if (!fread(buf, (cl < sizeof(buf)) ? cl : sizeof(buf), 1, ser->f))
+				ast_mutex_lock(&ser->lock);
+				if (!fread(buf, (cl < sizeof(buf)) ? cl : sizeof(buf), 1, ser->f)) {
+					ast_mutex_unlock(&ser->lock);
 					goto cleanup;
-				if (req.socket.lock) 
-					ast_mutex_unlock(req.socket.lock);
+				}
+				ast_mutex_unlock(&ser->lock);
 				if (me->stop)
 					goto cleanup;
 				cl -= strlen(buf);
@@ -2405,7 +2389,8 @@ cleanup:
 	ast_free(me);
 cleanup2:
 	fclose(ser->f);
-	ser = ast_tcptls_session_instance_destroy(ser);
+	ser->f = NULL;
+	ser->fd = -1;
 	if (reqcpy.data)
 		ast_free(reqcpy.data);
 	if (req.data) {
@@ -2414,11 +2399,8 @@ cleanup2:
 	}
 	
 
-	if (req.socket.lock) {
-		ast_mutex_destroy(req.socket.lock);
-		ast_free(req.socket.lock);
-		req.socket.lock = NULL;
-	}
+	ao2_ref(ser, -1);
+	ser = NULL;
 
 	return NULL;
 }
@@ -2761,8 +2743,8 @@ static int __sip_xmit(struct sip_pvt *p, struct ast_str *data, int len)
 	if (sip_prepare_socket(p) < 0)
 		return XMIT_ERROR;
 
-	if (p->socket.lock)
-		ast_mutex_lock(p->socket.lock);
+	if (p->socket.ser)
+		ast_mutex_lock(&p->socket.ser->lock);
 
 	if (p->socket.type & SIP_TRANSPORT_UDP) 
 		res = sendto(p->socket.fd, data->str, len, 0, (const struct sockaddr *)dst, sizeof(struct sockaddr_in));
@@ -2773,8 +2755,8 @@ static int __sip_xmit(struct sip_pvt *p, struct ast_str *data, int len)
 			ast_debug(1, "No p->socket.ser->f len=%d\n", len);
 	} 
 
-	if (p->socket.lock)
-		ast_mutex_unlock(p->socket.lock);
+	if (p->socket.ser)
+		ast_mutex_unlock(&p->socket.ser->lock);
 
 	if (res == -1) {
 		switch (errno) {
@@ -3780,6 +3762,11 @@ static void sip_destroy_peer(struct sip_peer *peer)
 	if (peer->dnsmgr)
 		ast_dnsmgr_release(peer->dnsmgr);
 	clear_peer_mailboxes(peer);
+
+	if (peer->socket.ser) {
+		ao2_ref(peer->socket.ser, -1);
+		peer->socket.ser = NULL;
+	}
 }
 
 /*! \brief Update peer data in database (if used) */
@@ -4201,6 +4188,20 @@ static void set_t38_capabilities(struct sip_pvt *p)
 	}
 }
 
+static void copy_socket_data(struct sip_socket *to_sock, const struct sip_socket *from_sock)
+{
+	if (to_sock->ser) {
+		ao2_ref(to_sock->ser, -1);
+		to_sock->ser = NULL;
+	}
+
+	if (from_sock->ser) {
+		ao2_ref(from_sock->ser, +1);
+	}
+
+	*to_sock = *from_sock;
+}
+
 /*! \brief Create address structure from peer reference.
  *	This function copies data from peer to the dialog, so we don't have to look up the peer
  *	again from memory or database during the life time of the dialog.
@@ -4210,7 +4211,7 @@ static void set_t38_capabilities(struct sip_pvt *p)
  */
 static int create_addr_from_peer(struct sip_pvt *dialog, struct sip_peer *peer)
 {
-	dialog->socket = peer->socket;
+	copy_socket_data(&dialog->socket, &peer->socket);
 
 	if ((peer->addr.sin_addr.s_addr || peer->defaddr.sin_addr.s_addr) &&
 	    (!peer->maxms || ((peer->lastms >= 0)  && (peer->lastms <= peer->maxms)))) {
@@ -4652,7 +4653,11 @@ static void __sip_destroy(struct sip_pvt *p, int lockowner, int lockdialoglist)
 	}
 
 	ast_string_field_free_memory(p);
-	return;
+
+	if (p->socket.ser) {
+		ao2_ref(p->socket.ser, -1);
+		p->socket.ser = NULL;
+	}
 }
 
 /*! \brief  update_call_counter: Handle call_limit for SIP users 
@@ -7946,11 +7951,7 @@ static int transmit_response_using_temp(ast_string_field callid, struct sockaddr
 	build_via(p);
 	ast_string_field_set(p, callid, callid);
 
-	p->socket.lock = req->socket.lock;
-	p->socket.type = req->socket.type;
-	p->socket.fd = req->socket.fd;
-	p->socket.port = req->socket.port;
-	p->socket.ser = req->socket.ser;
+	copy_socket_data(&p->socket, &req->socket);
 
 	/* Use this temporary pvt structure to send the message */
 	__transmit_response(p, msg, req, XMIT_UNRELIABLE);
@@ -10317,7 +10318,8 @@ static enum parse_register_result parse_register_contact(struct sip_pvt *pvt, st
 		}
 	}
 
-	pvt->socket = peer->socket = req->socket;
+	copy_socket_data(&peer->socket, &req->socket);
+	copy_socket_data(&pvt->socket, &peer->socket);
 
 	/* Look for brackets */
 	curi = contact;
@@ -19436,7 +19438,6 @@ static int sipsock_read(int *id, int fd, short events, void *ignore)
 	req.socket.type = SIP_TRANSPORT_UDP;
 	req.socket.ser	= NULL;
 	req.socket.port = bindaddr.sin_port;
-	req.socket.lock = NULL;
 
 	handle_request_do(&req, &sin);
 	if (req.data) {
@@ -19491,7 +19492,7 @@ static int handle_request_do(struct sip_request *req, struct sockaddr_in *sin)
 			return 1;
 		}
 
-		p->socket = req->socket;
+		copy_socket_data(&p->socket, &req->socket);
 
 		/* Go ahead and lock the owner if it has one -- we may need it */
 		/* becaues this is deadlock-prone, we need to try and unlock if failed */
@@ -19589,13 +19590,18 @@ static int sip_prepare_socket(struct sip_pvt *p)
 
 	if ((ser = sip_tcp_locate(&ca.sin))) {
 		s->fd = ser->fd;
+		if (s->ser) {
+			ao2_ref(s->ser, -1);
+			s->ser = NULL;
+		}
+		ao2_ref(ser, +1);
 		s->ser = ser;
 		return s->fd;
 	}
 
-	if (s->ser && s->ser->parent->tls_cfg) 
+	if (s->ser && s->ser->parent->tls_cfg) {
 		ca.tls_cfg = s->ser->parent->tls_cfg;
-	else {
+	} else {
 		if (s->type & SIP_TRANSPORT_TLS) {
 			ca.tls_cfg = ast_calloc(1, sizeof(*ca.tls_cfg));
 			if (!ca.tls_cfg)
@@ -19605,7 +19611,12 @@ static int sip_prepare_socket(struct sip_pvt *p)
 				ast_copy_string(ca.hostname, p->tohost, sizeof(ca.hostname));
 		}
 	}
-	s->ser = (!s->ser) ? ast_tcptls_client_start(&ca) : s->ser;
+	
+	if (s->ser) {
+		/* the pvt socket already has a server instance ... */
+	} else {
+		s->ser = ast_tcptls_client_start(&ca);
+	}
 
 	if (!s->ser) {
 		if (ca.tls_cfg)
@@ -19615,8 +19626,12 @@ static int sip_prepare_socket(struct sip_pvt *p)
 
 	s->fd = ca.accept_fd;
 
-	if (ast_pthread_create_background(&ca.master, NULL, sip_tcp_helper_thread, p)) {
+	/* Give the new thread a reference */
+	ao2_ref(s->ser, +1);
+
+	if (ast_pthread_create_background(&ca.master, NULL, sip_tcp_worker_fn, s->ser)) {
 		ast_debug(1, "Unable to launch '%s'.", ca.name);
+		ao2_ref(s->ser, -1);
 		close(ca.accept_fd);
 		s->fd = ca.accept_fd = -1;
 	}