freetdm: Clean up SS7 native bridge code to separate the call control, queuing and

         resource-cleanup responsibilities clearly between the 2 channels involved in the bridge

   - Each channel is responsible for clearning its own peer_data and event queue
     at the end of the call (when moving to DOWN state)

   - Each channel dequeues messages only from its own queue and enqueues messages
     in the peer's queue, with the only exception being messages received before
     the bridge is stablished (IAM for sure and possible SAM messages) because
     if the bridge is not yet stablished the messages must be queued by the channel
     in its own queue temporarily until the bridge is ready

   - When the bridge is ready it is the responsibility of the incoming channel to
     move the messages that stored temporarily in its own queue to the bridged peer queue

   - During hangup, each channel is responsible for moving itself to DOWN. The procedure
     however differs slightly depending on the hangup conditions

     If the user requests hangup (ie, FreeSWITCH) the request will be noted by setting the
     FTDM_CHANNEL_USER_HANGUP flag but will not be processed yet because call control is
     driven only by the link messages (so no hangup from ESL or command line allowed)

     When REL message comes, the channel receiving it must move to TERMINATING state and:

           - If the user has not hangup yet (FTDM_CHANNEL_USER_HANGUP flag not set) then
             notify the user via SIGEVENT_STOP and wait for the user to move to HANGUP
             state by calling ftdm_channel_call_hangup() before sending RLC

           - If the user did hangup already (FTDM_CHANNEL_USER_HANGUP flag is set) then
             skip user notification and move to HANGUP state directly where the RLC message
             will be sent

   - On HANGUP state the RLC is sent and the channel is moved to DOWN, final state
     The peer channel will forward the REL message and wait for RLC from the network, when
     RLC is received the channel can move straight to DOWN itself because the peer channel
     is completing its own shutdown procedure when it received the REL message

libs/freetdm/src/ftmod/ftmod_sangoma_ss7/ftmod_sangoma_ss7_in.c

@@ -81,6 +81,7 @@ void sngss7_con_ind(uint32_t suInstId, uint32_t spInstId, uint32_t circuit, SiCo
 
 	/* initalize the sngss7_event */
 	sngss7_event = ftdm_malloc(sizeof(*sngss7_event));
+	
 	if (sngss7_event == NULL) {
 		SS7_ERROR("Failed to allocate memory for sngss7_event!\n");
 		SS7_FUNC_TRACE_EXIT(__FUNCTION__);

libs/freetdm/src/ftmod/ftmod_sangoma_ss7/ftmod_sangoma_ss7_main.h

@@ -522,7 +522,8 @@ typedef struct sngss7_chan_data {
 	sngss7_group_data_t		tx_grs;
 	sngss7_group_data_t		ucic;
 	ftdm_queue_t 			*event_queue;
-	struct sngss7_chan_data *peer_data;
+	struct sngss7_chan_data         *peer_data;
+	uint8_t peer_event_transfer_cnt;
 } sngss7_chan_data_t;
 
 #define SNGSS7_RX_GRS_PENDING (1 << 0)
@@ -536,7 +537,6 @@ typedef struct sngss7_span_data {
 	sngss7_group_data_t		rx_cgu;
 	sngss7_group_data_t		tx_cgu;
 	ftdm_queue_t 			*event_queue;
-	ftdm_queue_t                    *peer_chans;
 } sngss7_span_data_t;
 
 typedef struct sngss7_event_data
@@ -970,7 +970,7 @@ if (ftdmchan->state == new_state) { \
 #define SS7_INFO_CHAN(fchan, msg, args...)	ftdm_log_chan(fchan, FTDM_LOG_INFO, msg , ##args)
 #define SS7_WARN_CHAN(fchan, msg, args...)	ftdm_log_chan(fchan, FTDM_LOG_WARNING, msg , ##args)
 #define SS7_ERROR_CHAN(fchan, msg, args...)	ftdm_log_chan(fchan, FTDM_LOG_ERROR, msg , ##args)
-#define SS7_CTRIT_CHAN(fchan, msg, args...)	ftdm_log_chan(fchan, FTDM_LOG_CRIT, msg , ##args)
+#define SS7_CRIT_CHAN(fchan, msg, args...)	ftdm_log_chan(fchan, FTDM_LOG_CRIT, msg , ##args)
 
 #ifdef SS7_CODE_DEVEL
 #define SS7_DEVEL_DEBUG(a,...)   ftdm_log(FTDM_LOG_DEBUG,a,##__VA_ARGS__ );

libs/freetdm/src/ftmod/ftmod_sangoma_ss7/ftmod_sangoma_ss7_out.c

@@ -48,6 +48,7 @@ void ft_to_sngss7_iam (ftdm_channel_t * ftdmchan)
 	SiConEvnt 			iam;
 	ftdm_bool_t         native_going_up = FTDM_FALSE;
 	sngss7_chan_data_t	*sngss7_info = ftdmchan->call_data;;
+	sngss7_event_data_t *event_clone = NULL;
 	
 	SS7_FUNC_TRACE_ENTER (__FUNCTION__);
 	
@@ -72,33 +73,28 @@ void ft_to_sngss7_iam (ftdm_channel_t * ftdmchan)
 						var, peer_span->signal_type);
 			} else {
 				peer_info = peer_chan->call_data;
-				if (peer_info) {
-					SS7_INFO_CHAN(ftdmchan,"[CIC:%d]Starting native bridge with peer CIC %d\n", 
-							sngss7_info->circuit->cic, peer_info->circuit->cic);
-
-					/* make each one of us aware of the native bridge */
-					peer_info->peer_data = sngss7_info;
-					sngss7_info->peer_data = peer_info;
-
-					/* flush our own queue */
-					sngss7_flush_queue(sngss7_info->event_queue);
-
-					/* Go to up until release comes, note that state processing is done different and much simpler when there is a peer,
-					   We can't go to UP state right away yet though, so do not set the state to UP here, wait until the end of this function
-					   because moving from one state to another causes the ftdmchan->usrmsg structure to be wiped 
-					   and we still need those variables for further IAM processing */
-					native_going_up = FTDM_TRUE;
-				}
+				SS7_INFO_CHAN(ftdmchan,"[CIC:%d]Starting native bridge with peer CIC %d\n", 
+						sngss7_info->circuit->cic, peer_info->circuit->cic);
+
+				/* retrieve only first message from the others guys queue (must be IAM) */
+				event_clone = ftdm_queue_dequeue(peer_info->event_queue);
+
+				/* make each one of us aware of the native bridge */
+				peer_info->peer_data = sngss7_info;
+				sngss7_info->peer_data = peer_info;
+
+				/* Go to up until release comes, note that state processing is done different and much simpler when there is a peer,
+				   We can't go to UP state right away yet though, so do not set the state to UP here, wait until the end of this function
+				   because moving from one state to another causes the ftdmchan->usrmsg structure to be wiped 
+				   and we still need those variables for further IAM processing */
+				native_going_up = FTDM_TRUE;
 			}
 		}
 	}
 
-	if (ftdm_test_flag(ftdmchan, FTDM_CHANNEL_NATIVE_SIGBRIDGE) && sngss7_info->peer_data) {
-		sngss7_span_data_t *span_data = ftdmchan->span->signal_data;
-		sngss7_event_data_t *event_clone = ftdm_queue_dequeue(sngss7_info->peer_data->event_queue);
-		/* Retrieve IAM from our peer */
+	if (ftdm_test_flag(ftdmchan, FTDM_CHANNEL_NATIVE_SIGBRIDGE)) {
 		if (!event_clone) {
-			SS7_ERROR_CHAN(ftdmchan, "No event clone in peer queue!%s\n", "");
+			SS7_ERROR_CHAN(ftdmchan, "No IAM event clone in peer queue!%s\n", "");
 		} else if (event_clone->event_id != SNGSS7_CON_IND_EVENT) {
 			/* first message in the queue should ALWAYS be an IAM */
 			SS7_ERROR_CHAN(ftdmchan, "Invalid initial peer message type '%d'\n", event_clone->event_id);
@@ -143,9 +139,6 @@ void ft_to_sngss7_iam (ftdm_channel_t * ftdmchan)
 				copy_ocn_to_sngss7(ftdmchan, &iam.origCdNum);
 			}
 		}
-		/* since this is the first time we dequeue an event from the peer, make sure our main thread process any other events,
-		   this will trigger the interrupt in our span peer_chans queue which will wake up our main thread if it is sleeping */
-		ftdm_queue_enqueue(span_data->peer_chans, sngss7_info->peer_data->ftdmchan);
 	} else if (sngss7_info->circuit->transparent_iam &&
 		sngss7_retrieve_iam(ftdmchan, &iam) == FTDM_SUCCESS) {
 		SS7_INFO_CHAN(ftdmchan,"[CIC:%d]Tx IAM (Transparent)\n", sngss7_info->circuit->cic);
@@ -236,7 +229,9 @@ void ft_to_sngss7_iam (ftdm_channel_t * ftdmchan)
 		  the user sending FTDM_SIGEVENT_UP which can cause the application to misbehave (ie, no audio) */
 		ftdm_set_state(ftdmchan, FTDM_CHANNEL_STATE_UP);
 		ftdm_channel_advance_states(ftdmchan);
-    }
+	}
+	
+	ftdm_safe_free(event_clone);
 
 	SS7_FUNC_TRACE_EXIT (__FUNCTION__);
 	return;