chan_pjsip: Fix deadlock when masquerading PJSIP channels.
authorRichard Mudgett <rmudgett@digium.com>
Fri, 3 Oct 2014 17:47:42 +0000 (17:47 +0000)
committerRichard Mudgett <rmudgett@digium.com>
Fri, 3 Oct 2014 17:47:42 +0000 (17:47 +0000)
Performing a directed call pickup resulted in a deadlock when PJSIP
channels were involved.

A masquerade needs to hold onto the channel locks while it swaps channel
information between the two channels involved in the masquerade.  With
PJSIP channels, the fixup routine needed to push a fixup task onto the
PJSIP channel's serializer.  Unfortunately, if the serializer was also
processing a task that needed to lock the channel, you get deadlock.

* Added a new control frame that is used to notify the channels that a
masquerade is about to start and when it has completed.

* Added the ability to query taskprocessors if the current thread is the
taskprocessor thread.

* Added the ability to suspend/unsuspend the PJSIP serializer thread so a
masquerade could fixup the PJSIP channel without using the serializer.

ASTERISK-24356 #close
Reported by: rmudgett

Review: https://reviewboard.asterisk.org/r/4034/
........

Merged revisions 424471 from http://svn.asterisk.org/svn/asterisk/branches/12
........

Merged revisions 424472 from http://svn.asterisk.org/svn/asterisk/branches/13

git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@424473 65c4cc65-6c06-0410-ace0-fbb531ad65f3

18 files changed:
addons/chan_ooh323.c
channels/chan_iax2.c
channels/chan_misdn.c
channels/chan_motif.c
channels/chan_pjsip.c
channels/chan_sip.c
channels/chan_skinny.c
channels/chan_unistim.c
funcs/func_frame_trace.c
include/asterisk/frame.h
include/asterisk/res_pjsip_session.h
include/asterisk/taskprocessor.h
main/bridge_channel.c
main/channel.c
main/core_unreal.c
main/taskprocessor.c
res/res_pjsip_session.c
res/res_pjsip_session.exports.in

index 8fd02cc..1a9ab38 100644 (file)
@@ -1396,6 +1396,7 @@ static int ooh323_indicate(struct ast_channel *ast, int condition, const void *d
                break;
        case AST_CONTROL_PROCEEDING:
        case AST_CONTROL_PVT_CAUSE_CODE:
+       case AST_CONTROL_MASQUERADE_NOTIFY:
        case -1:
                break;
        default:
index a3fb34c..d093438 100644 (file)
@@ -1421,6 +1421,8 @@ static int iax2_is_control_frame_allowed(int subtype)
                /* Only meaningful across a bridge on this machine for direct-media exchange. */
        case AST_CONTROL_PVT_CAUSE_CODE:
                /* Intended only for the sending machine's local channel structure. */
+       case AST_CONTROL_MASQUERADE_NOTIFY:
+               /* Intended only for masquerades when calling ast_indicate_data(). */
        case AST_CONTROL_STREAM_STOP:
        case AST_CONTROL_STREAM_SUSPEND:
        case AST_CONTROL_STREAM_RESTART:
@@ -5770,6 +5772,7 @@ static int iax2_indicate(struct ast_channel *c, int condition, const void *data,
                }
                break;
        case AST_CONTROL_PVT_CAUSE_CODE:
+       case AST_CONTROL_MASQUERADE_NOTIFY:
                res = -1;
                goto done;
        }
index f3d540d..8011b8f 100644 (file)
@@ -7108,6 +7108,7 @@ static int misdn_indication(struct ast_channel *ast, int cond, const void *data,
                chan_misdn_log(1, p->bc->port, " --> * Unknown Indication:%d pid:%d\n", cond, p->bc->pid);
                /* fallthrough */
        case AST_CONTROL_PVT_CAUSE_CODE:
+       case AST_CONTROL_MASQUERADE_NOTIFY:
                return -1;
        }
 
index 374632f..2582a0e 100644 (file)
@@ -1805,6 +1805,7 @@ static int jingle_indicate(struct ast_channel *ast, int condition, const void *d
        case AST_CONTROL_CONNECTED_LINE:
                break;
        case AST_CONTROL_PVT_CAUSE_CODE:
+       case AST_CONTROL_MASQUERADE_NOTIFY:
        case -1:
                res = -1;
                break;
index 015cd64..ea55df7 100644 (file)
@@ -701,40 +701,24 @@ static int chan_pjsip_write(struct ast_channel *ast, struct ast_frame *frame)
        return res;
 }
 
-struct fixup_data {
-       struct ast_sip_session *session;
-       struct ast_channel *chan;
-};
-
-static int fixup(void *data)
-{
-       struct fixup_data *fix_data = data;
-       struct ast_sip_channel_pvt *channel = ast_channel_tech_pvt(fix_data->chan);
-       struct chan_pjsip_pvt *pvt = channel->pvt;
-
-       channel->session->channel = fix_data->chan;
-       set_channel_on_rtp_instance(pvt, ast_channel_uniqueid(fix_data->chan));
-
-       return 0;
-}
-
 /*! \brief Function called by core to change the underlying owner channel */
 static int chan_pjsip_fixup(struct ast_channel *oldchan, struct ast_channel *newchan)
 {
        struct ast_sip_channel_pvt *channel = ast_channel_tech_pvt(newchan);
-       struct fixup_data fix_data;
-
-       fix_data.session = channel->session;
-       fix_data.chan = newchan;
+       struct chan_pjsip_pvt *pvt = channel->pvt;
 
        if (channel->session->channel != oldchan) {
                return -1;
        }
 
-       if (ast_sip_push_task_synchronous(channel->session->serializer, fixup, &fix_data)) {
-               ast_log(LOG_WARNING, "Unable to perform channel fixup\n");
-               return -1;
-       }
+       /*
+        * The masquerade has suspended the channel's session
+        * serializer so we can safely change it outside of
+        * the serializer thread.
+        */
+       channel->session->channel = newchan;
+
+       set_channel_on_rtp_instance(pvt, ast_channel_uniqueid(newchan));
 
        return 0;
 }
@@ -1211,6 +1195,24 @@ static int chan_pjsip_indicate(struct ast_channel *ast, int condition, const voi
        case AST_CONTROL_PVT_CAUSE_CODE:
                res = -1;
                break;
+       case AST_CONTROL_MASQUERADE_NOTIFY:
+               ast_assert(datalen == sizeof(int));
+               if (*(int *) data) {
+                       /*
+                        * Masquerade is beginning:
+                        * Wait for session serializer to get suspended.
+                        */
+                       ast_channel_unlock(ast);
+                       ast_sip_session_suspend(channel->session);
+                       ast_channel_lock(ast);
+               } else {
+                       /*
+                        * Masquerade is complete:
+                        * Unsuspend the session serializer.
+                        */
+                       ast_sip_session_unsuspend(channel->session);
+               }
+               break;
        case AST_CONTROL_HOLD:
                chan_pjsip_add_hold(ast_channel_uniqueid(ast));
                device_buf_size = strlen(ast_channel_name(ast)) + 1;
index 57586e8..cb02d31 100644 (file)
@@ -7853,6 +7853,7 @@ static int sip_indicate(struct ast_channel *ast, int condition, const void *data
                res = -1;
                break;
        case AST_CONTROL_PVT_CAUSE_CODE: /* these should be handled by the code in channel.c */
+       case AST_CONTROL_MASQUERADE_NOTIFY:
        case -1:
                res = -1;
                break;
index 1cfb3a7..4b7f353 100644 (file)
@@ -5336,6 +5336,7 @@ static int skinny_indicate(struct ast_channel *ast, int ind, const void *data, s
                ast_log(LOG_WARNING, "Don't know how to indicate condition %d\n", ind);
                /* fallthrough */
        case AST_CONTROL_PVT_CAUSE_CODE:
+       case AST_CONTROL_MASQUERADE_NOTIFY:
                return -1; /* Tell asterisk to provide inband signalling */
        }
        return 0;
index caa60ad..7820d05 100644 (file)
@@ -5369,6 +5369,7 @@ static int unistim_indicate(struct ast_channel *ast, int ind, const void *data,
                ast_log(LOG_WARNING, "Don't know how to indicate condition %d\n", ind);
                /* fallthrough */
        case AST_CONTROL_PVT_CAUSE_CODE:
+       case AST_CONTROL_MASQUERADE_NOTIFY:
                return -1;
        }
 
index 3ad048d..512d685 100644 (file)
@@ -334,6 +334,10 @@ static void print_frame(struct ast_frame *frame)
                case AST_CONTROL_PVT_CAUSE_CODE:
                        ast_verbose("SubClass: PVT_CAUSE_CODE\n");
                        break;
+               case AST_CONTROL_MASQUERADE_NOTIFY:
+                       /* Should never happen. */
+                       ast_assert(0);
+                       break;
                case AST_CONTROL_STREAM_STOP:
                        ast_verbose("SubClass: STREAM_STOP\n");
                        break;
index a981c7e..20f40f8 100644 (file)
@@ -290,6 +290,7 @@ enum ast_control_frame_type {
        AST_CONTROL_MCID = 31,                  /*!< Indicate that the caller is being malicious. */
        AST_CONTROL_UPDATE_RTP_PEER = 32, /*!< Interrupt the bridge and have it update the peer */
        AST_CONTROL_PVT_CAUSE_CODE = 33, /*!< Contains an update to the protocol-specific cause-code stored for branching dials */
+       AST_CONTROL_MASQUERADE_NOTIFY = 34,     /*!< A masquerade is about to begin/end. (Never sent as a frame but directly with ast_indicate_data().) */
 
        /*
         * WARNING WARNING WARNING WARNING WARNING WARNING WARNING WARNING WARNING
index 010a74d..3344a6b 100644 (file)
@@ -87,6 +87,9 @@ struct ast_sip_session_media {
  */
 struct ast_sip_session_delayed_request;
 
+/*! \brief Opaque struct controlling the suspension of the session's serializer. */
+struct ast_sip_session_suspender;
+
 /*!
  * \brief A structure describing a SIP session
  *
@@ -96,43 +99,45 @@ struct ast_sip_session_delayed_request;
  * to use the term "SIP session" to refer to the INVITE dialog itself.
  */
 struct ast_sip_session {
-       /* Dialplan extension where incoming call is destined */
+       /*! Dialplan extension where incoming call is destined */
        char exten[AST_MAX_EXTENSION];
-       /* The endpoint with which Asterisk is communicating */
+       /*! The endpoint with which Asterisk is communicating */
        struct ast_sip_endpoint *endpoint;
-       /* The contact associated with this session */
+       /*! The contact associated with this session */
        struct ast_sip_contact *contact;
-       /* The PJSIP details of the session, which includes the dialog */
+       /*! The PJSIP details of the session, which includes the dialog */
        struct pjsip_inv_session *inv_session;
-       /* The Asterisk channel associated with the session */
+       /*! The Asterisk channel associated with the session */
        struct ast_channel *channel;
-       /* Registered session supplements */
+       /*! Registered session supplements */
        AST_LIST_HEAD(, ast_sip_session_supplement) supplements;
-       /* Datastores added to the session by supplements to the session */
+       /*! Datastores added to the session by supplements to the session */
        struct ao2_container *datastores;
-       /* Media streams */
+       /*! Media streams */
        struct ao2_container *media;
-       /* Serializer for tasks relating to this SIP session */
+       /*! Serializer for tasks relating to this SIP session */
        struct ast_taskprocessor *serializer;
-       /* Requests that could not be sent due to current inv_session state */
+       /*! Non-null if the session serializer is suspended or being suspended. */
+       struct ast_sip_session_suspender *suspended;
+       /*! Requests that could not be sent due to current inv_session state */
        AST_LIST_HEAD_NOLOCK(, ast_sip_session_delayed_request) delayed_requests;
-       /* When we need to reschedule a reinvite, we use this structure to do it */
+       /*! When we need to reschedule a reinvite, we use this structure to do it */
        pj_timer_entry rescheduled_reinvite;
-       /* Format capabilities pertaining to direct media */
+       /*! Format capabilities pertaining to direct media */
        struct ast_format_cap *direct_media_cap;
-       /* When we need to forcefully end the session */
+       /*! When we need to forcefully end the session */
        pj_timer_entry scheduled_termination;
-       /* Identity of endpoint this session deals with */
+       /*! Identity of endpoint this session deals with */
        struct ast_party_id id;
-       /* Requested capabilities */
+       /*! Requested capabilities */
        struct ast_format_cap *req_caps;
-       /* Optional DSP, used only for inband DTMF detection if configured */
+       /*! Optional DSP, used only for inband DTMF detection if configured */
        struct ast_dsp *dsp;
-       /* Whether the termination of the session should be deferred */
+       /*! Whether the termination of the session should be deferred */
        unsigned int defer_terminate:1;
-       /* Deferred incoming re-invite */
+       /*! Deferred incoming re-invite */
        pjsip_rx_data *deferred_reinvite;
-       /* Current T.38 state */
+       /*! Current T.38 state */
        enum ast_sip_session_t38state t38state;
 };
 
@@ -388,6 +393,28 @@ struct ast_sip_session *ast_sip_session_alloc(struct ast_sip_endpoint *endpoint,
        struct ast_sip_contact *contact, pjsip_inv_session *inv);
 
 /*!
+ * \brief Request and wait for the session serializer to be suspended.
+ * \since 12.7.0
+ *
+ * \param session Which session to suspend the serializer.
+ *
+ * \note No channel locks can be held while calling without risk of deadlock.
+ *
+ * \return Nothing
+ */
+void ast_sip_session_suspend(struct ast_sip_session *session);
+
+/*!
+ * \brief Request the session serializer be unsuspended.
+ * \since 12.7.0
+ *
+ * \param session Which session to unsuspend the serializer.
+ *
+ * \return Nothing
+ */
+void ast_sip_session_unsuspend(struct ast_sip_session *session);
+
+/*!
  * \brief Create a new outgoing SIP session
  *
  * The endpoint that is passed in will have its reference count increased by one since
index ab52329..f16f144 100644 (file)
@@ -247,6 +247,16 @@ int ast_taskprocessor_push_local(struct ast_taskprocessor *tps,
 int ast_taskprocessor_execute(struct ast_taskprocessor *tps);
 
 /*!
+ * \brief Am I the given taskprocessor's current task.
+ * \since 12.7.0
+ *
+ * \param tps Taskprocessor to check.
+ *
+ * \retval non-zero if current thread is the taskprocessor thread.
+ */
+int ast_taskprocessor_is_task(struct ast_taskprocessor *tps);
+
+/*!
  * \brief Return the name of the taskprocessor singleton
  * \since 1.6.1
  */
index 5bf8512..d94b738 100644 (file)
@@ -2065,6 +2065,10 @@ static void bridge_channel_handle_control(struct ast_bridge_channel *bridge_chan
                        ast_indicate(chan, -1);
                }
                break;
+       case AST_CONTROL_MASQUERADE_NOTIFY:
+               /* Should never happen. */
+               ast_assert(0);
+               break;
        default:
                ast_indicate_data(chan, fr->subclass.integer, fr->data.ptr, fr->datalen);
                break;
index 9100f26..47d47b6 100644 (file)
@@ -4285,6 +4285,7 @@ static int attribute_const is_visible_indication(enum ast_control_frame_type con
        case AST_CONTROL_MCID:
        case AST_CONTROL_UPDATE_RTP_PEER:
        case AST_CONTROL_PVT_CAUSE_CODE:
+       case AST_CONTROL_MASQUERADE_NOTIFY:
        case AST_CONTROL_STREAM_STOP:
        case AST_CONTROL_STREAM_SUSPEND:
        case AST_CONTROL_STREAM_REVERSE:
@@ -4451,7 +4452,9 @@ int ast_indicate_data(struct ast_channel *chan, int _condition,
        ast_channel_lock(chan);
 
        /* Don't bother if the channel is about to go away, anyway. */
-       if (ast_test_flag(ast_channel_flags(chan), AST_FLAG_ZOMBIE) || ast_check_hangup(chan)) {
+       if ((ast_test_flag(ast_channel_flags(chan), AST_FLAG_ZOMBIE)
+                       || ast_check_hangup(chan))
+               && condition != AST_CONTROL_MASQUERADE_NOTIFY) {
                res = -1;
                goto indicate_cleanup;
        }
@@ -4599,6 +4602,7 @@ int ast_indicate_data(struct ast_channel *chan, int _condition,
        case AST_CONTROL_AOC:
        case AST_CONTROL_END_OF_Q:
        case AST_CONTROL_MCID:
+       case AST_CONTROL_MASQUERADE_NOTIFY:
        case AST_CONTROL_UPDATE_RTP_PEER:
        case AST_CONTROL_STREAM_STOP:
        case AST_CONTROL_STREAM_SUSPEND:
@@ -6445,6 +6449,11 @@ static void channel_do_masquerade(struct ast_channel *original, struct ast_chann
         * original channel's backend.  While the features are nice, which is the
         * reason we're keeping it, it's still awesomely weird. XXX */
 
+       /* Indicate to each channel that a masquerade is about to begin. */
+       x = 1;
+       ast_indicate_data(original, AST_CONTROL_MASQUERADE_NOTIFY, &x, sizeof(x));
+       ast_indicate_data(clonechan, AST_CONTROL_MASQUERADE_NOTIFY, &x, sizeof(x));
+
        /*
         * The container lock is necessary for proper locking order
         * because the channels must be unlinked to change their
@@ -6485,8 +6494,9 @@ static void channel_do_masquerade(struct ast_channel *original, struct ast_chann
        /* Start the masquerade channel contents rearangement. */
        ast_channel_lock_both(original, clonechan);
 
-       ast_debug(4, "Actually Masquerading %s(%u) into the structure of %s(%u)\n",
-               ast_channel_name(clonechan), ast_channel_state(clonechan), ast_channel_name(original), ast_channel_state(original));
+       ast_debug(1, "Actually Masquerading %s(%u) into the structure of %s(%u)\n",
+               ast_channel_name(clonechan), ast_channel_state(clonechan),
+               ast_channel_name(original), ast_channel_state(original));
 
        /*
         * Remember the original read/write formats.  We turn off any
@@ -6759,6 +6769,19 @@ static void channel_do_masquerade(struct ast_channel *original, struct ast_chann
        ast_channel_unlock(original);
        ast_channel_unlock(clonechan);
 
+       /*
+        * Indicate to each channel that a masquerade is complete.
+        *
+        * We can still do this to clonechan even though it is a
+        * zombie because ast_indicate_data() will explicitly pass
+        * this control and ast_hangup() is held off until the
+        * ast_channel_masq() and ast_channel_masqr() pointers are
+        * cleared.
+        */
+       x = 0;
+       ast_indicate_data(original, AST_CONTROL_MASQUERADE_NOTIFY, &x, sizeof(x));
+       ast_indicate_data(clonechan, AST_CONTROL_MASQUERADE_NOTIFY, &x, sizeof(x));
+
        ast_bridge_notify_masquerade(original);
 
        if (clone_hold_state == AST_CONTROL_HOLD) {
index b3dc528..90ed3fb 100644 (file)
@@ -530,6 +530,12 @@ int ast_unreal_indicate(struct ast_channel *ast, int condition, const void *data
        ao2_ref(p, 1); /* ref for unreal_queue_frame */
 
        switch (condition) {
+       case AST_CONTROL_MASQUERADE_NOTIFY:
+               /*
+                * Always block this because this is the channel being
+                * masqueraded; not anything down the chain.
+                */
+               break;
        case AST_CONTROL_CONNECTED_LINE:
        case AST_CONTROL_REDIRECTING:
                res = unreal_colp_redirect_indicate(p, ast, condition);
index 0582f76..5fbbca5 100644 (file)
@@ -78,9 +78,9 @@ struct ast_taskprocessor {
        long tps_queue_size;
        /*! \brief Taskprocessor queue */
        AST_LIST_HEAD_NOLOCK(tps_queue, tps_task) tps_queue;
-       /*! \brief Taskprocessor singleton list entry */
-       AST_LIST_ENTRY(ast_taskprocessor) list;
        struct ast_taskprocessor_listener *listener;
+       /*! Current thread executing the tasks */
+       pthread_t thread;
        /*! Indicates if the taskprocessor is currently executing a task */
        unsigned int executing:1;
 };
@@ -600,6 +600,8 @@ static struct ast_taskprocessor *__allocate_taskprocessor(const char *name, stru
        ao2_ref(listener, +1);
        p->listener = listener;
 
+       p->thread = AST_PTHREADT_NULL;
+
        ao2_ref(p, +1);
        listener->tps = p;
 
@@ -752,6 +754,7 @@ int ast_taskprocessor_execute(struct ast_taskprocessor *tps)
                return 0;
        }
 
+       tps->thread = pthread_self();
        tps->executing = 1;
 
        if (t->wants_local) {
@@ -768,6 +771,7 @@ int ast_taskprocessor_execute(struct ast_taskprocessor *tps)
        tps_task_free(t);
 
        ao2_lock(tps);
+       tps->thread = AST_PTHREADT_NULL;
        /* We need to check size in the same critical section where we reset the
         * executing bit. Avoids a race condition where a task is pushed right
         * after we pop an empty stack.
@@ -789,3 +793,13 @@ int ast_taskprocessor_execute(struct ast_taskprocessor *tps)
        }
        return size > 0;
 }
+
+int ast_taskprocessor_is_task(struct ast_taskprocessor *tps)
+{
+       int is_task;
+
+       ao2_lock(tps);
+       is_task = pthread_equal(tps->thread, pthread_self());
+       ao2_unlock(tps);
+       return is_task;
+}
index 42f7281..1d6b36f 100644 (file)
@@ -1223,6 +1223,108 @@ struct ast_sip_session *ast_sip_session_alloc(struct ast_sip_endpoint *endpoint,
        return session;
 }
 
+/*! \brief struct controlling the suspension of the session's serializer. */
+struct ast_sip_session_suspender {
+       ast_cond_t cond_suspended;
+       ast_cond_t cond_complete;
+       int suspended;
+       int complete;
+};
+
+static void sip_session_suspender_dtor(void *vdoomed)
+{
+       struct ast_sip_session_suspender *doomed = vdoomed;
+
+       ast_cond_destroy(&doomed->cond_suspended);
+       ast_cond_destroy(&doomed->cond_complete);
+}
+
+/*!
+ * \internal
+ * \brief Block the session serializer thread task.
+ *
+ * \param data Pushed serializer task data for suspension.
+ *
+ * \retval 0
+ */
+static int sip_session_suspend_task(void *data)
+{
+       struct ast_sip_session_suspender *suspender = data;
+
+       ao2_lock(suspender);
+
+       /* Signal that the serializer task is now suspended. */
+       suspender->suspended = 1;
+       ast_cond_signal(&suspender->cond_suspended);
+
+       /* Wait for the the serializer suspension to be completed. */
+       while (!suspender->complete) {
+               ast_cond_wait(&suspender->cond_complete, ao2_object_get_lockaddr(suspender));
+       }
+
+       ao2_unlock(suspender);
+       ao2_ref(suspender, -1);
+
+       return 0;
+}
+
+void ast_sip_session_suspend(struct ast_sip_session *session)
+{
+       struct ast_sip_session_suspender *suspender;
+       int res;
+
+       ast_assert(session->suspended == NULL);
+
+       if (ast_taskprocessor_is_task(session->serializer)) {
+               /* I am the session's serializer thread so I cannot suspend. */
+               return;
+       }
+
+       suspender = ao2_alloc(sizeof(*suspender), sip_session_suspender_dtor);
+       if (!suspender) {
+               /* We will just have to hope that the system does not deadlock */
+               return;
+       }
+       ast_cond_init(&suspender->cond_suspended, NULL);
+       ast_cond_init(&suspender->cond_complete, NULL);
+
+       ao2_ref(suspender, +1);
+       res = ast_sip_push_task(session->serializer, sip_session_suspend_task, suspender);
+       if (res) {
+               /* We will just have to hope that the system does not deadlock */
+               ao2_ref(suspender, -2);
+               return;
+       }
+
+       session->suspended = suspender;
+
+       /* Wait for the serializer to get suspended. */
+       ao2_lock(suspender);
+       while (!suspender->suspended) {
+               ast_cond_wait(&suspender->cond_suspended, ao2_object_get_lockaddr(suspender));
+       }
+       ao2_unlock(suspender);
+}
+
+void ast_sip_session_unsuspend(struct ast_sip_session *session)
+{
+       struct ast_sip_session_suspender *suspender = session->suspended;
+
+       if (!suspender) {
+               /* Nothing to do */
+               return;
+       }
+       session->suspended = NULL;
+
+       /* Signal that the serializer task suspension is now complete. */
+       ao2_lock(suspender);
+       suspender->complete = 1;
+       ast_cond_signal(&suspender->cond_complete);
+       ao2_unlock(suspender);
+
+       ao2_ref(suspender, -1);
+}
+
 static int session_outbound_auth(pjsip_dialog *dlg, pjsip_tx_data *tdata, void *user_data)
 {
        pjsip_inv_session *inv = pjsip_dlg_get_inv_session(dlg);
index 55274f9..07f26b7 100644 (file)
@@ -15,6 +15,8 @@
                LINKER_SYMBOL_PREFIXast_sip_session_send_request;
                LINKER_SYMBOL_PREFIXast_sip_session_create_invite;
                LINKER_SYMBOL_PREFIXast_sip_session_create_outgoing;
+               LINKER_SYMBOL_PREFIXast_sip_session_suspend;
+               LINKER_SYMBOL_PREFIXast_sip_session_unsuspend;
                LINKER_SYMBOL_PREFIXast_sip_dialog_get_session;
                LINKER_SYMBOL_PREFIXast_sip_session_resume_reinvite;
                LINKER_SYMBOL_PREFIXast_sip_channel_pvt_alloc;