Skinny: handle early media

See MODSKINNY-8 (switch_core_io.c:121
SKINNY/internal/SEP002699438FB6:0/1 has no read codec when using early
media)

src/mod/endpoints/mod_skinny/mod_skinny.c

@@ -972,9 +972,12 @@ switch_status_t channel_answer_channel(switch_core_session_t *session)
 
 switch_status_t channel_receive_message(switch_core_session_t *session, switch_core_session_message_t *msg)
 {
+	private_t *tech_pvt = switch_core_session_get_private(session);
+
 	switch (msg->message_id) {
 	case SWITCH_MESSAGE_INDICATE_ANSWER:
 		{
+			switch_clear_flag_locked(tech_pvt, TFLAG_EARLY_MEDIA);
 			channel_answer_channel(session);
 		}
 		break;
@@ -982,6 +985,14 @@ switch_status_t channel_receive_message(switch_core_session_t *session, switch_c
 		{
 			skinny_session_send_call_info_all(session);
 		}
+	case SWITCH_MESSAGE_INDICATE_PROGRESS:
+		{
+			if (!switch_test_flag(tech_pvt, TFLAG_EARLY_MEDIA)) {
+				/* early media */
+				switch_set_flag_locked(tech_pvt, TFLAG_EARLY_MEDIA);
+				channel_answer_channel(session);
+			}
+		}
 	default:
 		break;
 	}

src/mod/endpoints/mod_skinny/mod_skinny.h

@@ -146,10 +146,11 @@ typedef switch_status_t (*skinny_listener_callback_func_t) (listener_t *listener
 /* CHANNEL TYPES */
 /*****************************************************************************/
 typedef enum {
-    TFLAG_IO = (1 << 0),
-    TFLAG_READING = (1 << 9),
-    TFLAG_WRITING = (1 << 10),
-    TFLAG_FORCE_ROUTE = (1 << 11)
+    TFLAG_FORCE_ROUTE = (1 << 0),
+    TFLAG_EARLY_MEDIA = (1 << 1),
+    TFLAG_IO = (1 << 2),
+    TFLAG_READING = (1 << 3),
+    TFLAG_WRITING = (1 << 4)
 } TFLAGS;
 
 typedef enum {

src/mod/endpoints/mod_skinny/skinny_server.c

@@ -698,6 +698,7 @@ switch_status_t skinny_session_start_media(switch_core_session_t *session, liste
 	channel = switch_core_session_get_channel(session);
 	tech_pvt = switch_core_session_get_private(session);
 	
+	if (!switch_channel_test_flag(channel, CF_EARLY_MEDIA)) {
 		send_stop_tone(listener, line_instance, tech_pvt->call_id);
 		send_open_receive_channel(listener,
 			tech_pvt->call_id, /* uint32_t conference_id, */
@@ -709,6 +710,8 @@ switch_status_t skinny_session_start_media(switch_core_session_t *session, liste
 			0, /* uint32_t conference_id2, */
 			0 /* uint32_t reserved[10] */
 		);
+	}
+	if (!switch_test_flag(tech_pvt, TFLAG_EARLY_MEDIA)) {
 		skinny_line_set_state(listener, line_instance, tech_pvt->call_id, SKINNY_CONNECTED);
 		send_select_soft_keys(listener, line_instance, tech_pvt->call_id,
 			SKINNY_KEY_SET_CONNECTED, 0xffff);
@@ -717,6 +720,7 @@ switch_status_t skinny_session_start_media(switch_core_session_t *session, liste
 			SKINNY_DISP_CONNECTED,
 			line_instance,
 			tech_pvt->call_id);
+	}
 	skinny_session_send_call_info(session, listener, line_instance);
 
 	return SWITCH_STATUS_SUCCESS;