Make sip_destroy() return NULL so the caller can do things like

     foo = sip_destroy(foo);
and reduce the chance of bugs due to dangling pointers.

Also remove a duplicate prototype for the function.

nothing to backport.

git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@76392 65c4cc65-6c06-0410-ace0-fbb531ad65f3

diff --git a/channels/chan_sip.c b/channels/chan_sip.c
index fd9e3bae70e538e28567130a846c5ca708f34b13..79ab9df189b8abf07369bcc71e66973c5b0587f7 100644 (file)
--- a/channels/chan_sip.c
+++ b/channels/chan_sip.c
@@ -1402,7 +1402,7 @@ static struct sip_pvt *sip_alloc(ast_string_field callid, struct sockaddr_in *si
 static int __sip_autodestruct(void *data);
 static void sip_scheddestroy(struct sip_pvt *p, int ms);
 static void sip_cancel_destroy(struct sip_pvt *p);
-static void sip_destroy(struct sip_pvt *p);
+static struct sip_pvt *sip_destroy(struct sip_pvt *p);
 static void __sip_destroy(struct sip_pvt *p, int lockowner, int lockdialoglist);
 static void __sip_ack(struct sip_pvt *p, int seqno, int resp, int sipmethod);
 static void __sip_pretend_ack(struct sip_pvt *p);
@@ -1466,7 +1466,6 @@ static int reload_config(enum channelreloadreason reason);
 static int expire_register(void *data);
 static void *do_monitor(void *data);
 static int restart_monitor(void);
-static void sip_destroy(struct sip_pvt *p);
 static int sip_addrcmp(char *name, struct sockaddr_in *sin);   /* Support for peer matching */
 static int sip_refer_allocate(struct sip_pvt *p);
 static void ast_quiet_chan(struct ast_channel *chan);
@@ -2797,10 +2796,10 @@ static void sip_destroy_peer(struct sip_peer *peer)
 
        /* Delete it, it needs to disappear */
        if (peer->call)
-               sip_destroy(peer->call);
+               peer->call = sip_destroy(peer->call);
 
        if (peer->mwipvt)       /* We have an active subscription, delete it */
-               sip_destroy(peer->mwipvt);
+               peer->mwipvt = sip_destroy(peer->mwipvt);
 
        if (peer->mwi_event_sub) {
                ast_event_unsubscribe(peer->mwi_event_sub);
@@ -3370,7 +3369,7 @@ static void sip_registry_destroy(struct sip_registry *reg)
                   we don't get reentered trying to grab the registry lock */
                reg->call->registry = NULL;
                ast_debug(3, "Destroying active SIP dialog for registry %s@%s\n", reg->username, reg->hostname);
-               sip_destroy(reg->call);
+               reg->call = sip_destroy(reg->call);
        }
        if (reg->expire > -1)
                ast_sched_del(sched, reg->expire);
@@ -3599,11 +3598,16 @@ static int update_call_counter(struct sip_pvt *fup, int event)
        return 0;
 }
 
-/*! \brief Destroy SIP call structure */
-static void sip_destroy(struct sip_pvt *p)
+/*! \brief Destroy SIP call structure.
+ * Make it return NULL so the caller can do things like
+ *     foo = sip_destroy(foo);
+ * and reduce the chance of bugs due to dangling pointers.
+ */
+static struct sip_pvt * sip_destroy(struct sip_pvt *p)
 {
        ast_debug(3, "Destroying SIP dialog %s\n", p->callid);
        __sip_destroy(p, TRUE, TRUE);
+       return NULL;
 }
 
 /*! \brief Convert SIP hangup causes to Asterisk hangup causes */
@@ -16230,8 +16234,7 @@ static int sip_poke_noanswer(void *data)
                        register_peer_exten(peer, FALSE);
        }
        if (peer->call)
-               sip_destroy(peer->call);
-       peer->call = NULL;
+               peer->call = sip_destroy(peer->call);
        peer->lastms = -1;
        ast_device_state_changed("SIP/%s", peer->name);
        /* Try again quickly */
@@ -16260,7 +16263,7 @@ static int sip_poke_peer(struct sip_peer *peer)
        if (peer->call) {
                if (sipdebug)
                        ast_log(LOG_NOTICE, "Still have a QUALIFY dialog active, deleting\n");
-               sip_destroy(peer->call);
+               peer->call = sip_destroy(peer->call);
        }
        if (!(p = peer->call = sip_alloc(NULL, NULL, 0, SIP_OPTIONS)))
                return -1;
@@ -18338,7 +18341,7 @@ static int sip_do_reload(enum channelreloadreason reason)
                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 */
-                       sip_destroy(iterator->call);
+                       iterator->call = sip_destroy(iterator->call);
                }
                ASTOBJ_UNLOCK(iterator);