fix: discard incoming binary or text frame if we are shutting down to avoid deadlock (#84)

* append null to ostringstream will make c_str return part of a string.

* fixed review comment

Signed-off-by: Quan HL <quan.luuhoang8@gmail.com>

* fixed review comment

Signed-off-by: Quan HL <quan.luuhoang8@gmail.com>

* fixed review comment

Signed-off-by: Quan HL <quan.luuhoang8@gmail.com>

---------

Signed-off-by: Quan HL <quan.luuhoang8@gmail.com>

mod_audio_fork/audio_pipe.cpp

@@ -141,6 +141,11 @@ int AudioPipe::lws_callback(struct lws *wsi,
           return 0;
         }
         
+        if (ap->m_state == LWS_CLIENT_DISCONNECTING) {
+          lwsl_notice("AudioPipe::lws_service_thread race condition: got incoming message while closing the connection.\n");
+          return 0;
+        }
+
         if (lws_frame_is_binary(wsi)) {
           if (ap->is_bidirectional_audio_stream()) {
             ap->m_callback(ap->m_uuid.c_str(), ap->m_bugname.c_str(), AudioPipe::BINARY, NULL, (char *) in, len);

mod_azure_transcribe/azure_transcribe_glue.cpp

@@ -382,22 +382,18 @@ private:
 
 		const char* endpoint = switch_channel_get_variable(channel, "AZURE_SERVICE_ENDPOINT");
 		const char* endpointId = switch_channel_get_variable(channel, "AZURE_SERVICE_ENDPOINT_ID");
-		configuration_stream <<
-			endpoint << ";" <<
-			endpointId << ";";
+		configuration_stream << (endpoint ? endpoint : "") << ";"
+			<< (endpointId ? endpointId : "") << ";";
 		if (switch_true(switch_channel_get_variable(channel, "AZURE_USE_OUTPUT_FORMAT_DETAILED"))) {
 			configuration_stream << "output_format_detailed;";
 		}
 		if (switch_true(switch_channel_get_variable(channel, "AZURE_AUDIO_LOGGING"))) {
 			configuration_stream << "audio_logging;";
 		}
-		if (nullptr != proxyIP && nullptr != proxyPort) {
-			configuration_stream <<
-				proxyIP << ";" <<
-				proxyPort << ";" <<
-				proxyUsername << ";" <<
-				proxyPassword << ";";
-		}
+		configuration_stream << (proxyIP ? proxyIP : "") << ";"
+			<< (proxyPort ? proxyPort : "") << ";"
+			<< (proxyUsername ? proxyUsername : "") << ";"
+			<< (proxyPassword ? proxyPassword : "") << ";";
 		const char* var;
 		if (var = switch_channel_get_variable(channel, "AZURE_SPEECH_ALTERNATIVE_LANGUAGE_CODES")) {
 			configuration_stream << var << ";";