Improvements to mod_bert

* Added BERT stats channel variables

* Check if the channel is going down when out of sync to avoid flagging it
  as out of sync, if the channel is going down it is expected to have some errors

src/mod/applications/mod_bert/mod_bert.c

@@ -42,6 +42,7 @@ typedef struct {
 	uint32_t err_samples;
 	uint32_t window_ms;
 	uint32_t window_samples;
+	uint32_t stats_sync_lost_cnt;
 	uint8_t sequence_sample;
 	uint8_t predicted_sample;
 	float max_err;
@@ -84,6 +85,9 @@ typedef struct {
 		} \
 	} while (0);
 
+#define BERT_STATS_VAR_SYNC_LOST "bert_stats_sync_lost"
+#define BERT_STATS_VAR_SYNC_LOST_CNT "bert_stats_sync_lost_count"
+
 #define BERT_DEFAULT_WINDOW_MS 1000
 #define BERT_DEFAULT_MAX_ERR 10.0
 #define BERT_DEFAULT_TIMEOUT_MS 10000
@@ -168,6 +172,8 @@ SWITCH_STANDARD_APP(bert_test_function)
 		switch_log_printf(SWITCH_CHANNEL_SESSION_LOG(session), SWITCH_LOG_ERROR, "Failed to compute BERT window samples!\n");
 		goto done;
 	}
+	switch_channel_set_variable(channel, BERT_STATS_VAR_SYNC_LOST_CNT, "0");
+	switch_channel_set_variable(channel, BERT_STATS_VAR_SYNC_LOST, "false");
 	while (switch_channel_ready(channel)) {
 		uint8_t *read_samples = NULL;
 		uint8_t *write_samples = NULL;
@@ -210,12 +216,22 @@ SWITCH_STANDARD_APP(bert_test_function)
 		/* BERT Sync Loop */
 		for (i = 0; i < read_frame->samples; i++) {
 			if (bert.window_samples == bert.processed_samples) {
+				float err = 0.0;
+				/* If the channel is going down, then it is expected we'll have errors, ignore them and bail out */
+				if (!switch_channel_ready(channel)) {
+					bert_close_debug_streams(bert, session);
+					break;
+				}
 				/* Calculate error rate */
-				float err = ((float)((float)bert.err_samples / (float)bert.processed_samples) * 100.0);
+				err = ((float)((float)bert.err_samples / (float)bert.processed_samples) * 100.0);
 				if (err > bert.max_err) {
 					if (bert.in_sync) {
 						bert.in_sync = 0;
-						switch_log_printf(SWITCH_CHANNEL_SESSION_LOG(session), SWITCH_LOG_WARNING, "BERT Sync Lost: %f%% loss (err_samples=%u, session=%s)\n", err, bert.err_samples, switch_core_session_get_uuid(session));
+						bert.stats_sync_lost_cnt++;
+						switch_log_printf(SWITCH_CHANNEL_SESSION_LOG(session), SWITCH_LOG_WARNING, "BERT Sync Lost: %f%% loss (count=%u, err_samples=%u, session=%s)\n",
+								err, bert.stats_sync_lost_cnt, bert.err_samples, switch_core_session_get_uuid(session));
+						switch_channel_set_variable_printf(channel, BERT_STATS_VAR_SYNC_LOST_CNT, "%u", bert.stats_sync_lost_cnt);
+						switch_channel_set_variable(channel, BERT_STATS_VAR_SYNC_LOST, "true");
 						if (bert.hangup_on_error) {
 							switch_channel_hangup(channel, SWITCH_CAUSE_MEDIA_TIMEOUT);
 							bert_close_debug_streams(bert, session);