channels/chan_pjsip: Add PJSIP_SEND_SESSION_REFRESH

This patch adds a new PJSIP specific dialplan function,
PJSIP_SEND_SESSION_REFRESH. When invoked on a PJSIP channel, the media
session will be refreshed via either an UPDATE or re-INVITE request.
When used in conjunction with the PJSIP_MEDIA_OFFER dialplan function,
the formats in use on a PJSIP channel can be re-negotiated and changed
dynamically after call setup.

ASTERISK-26277 #close

Change-Id: Ib98fe09ba889aafe26d58d32f0fd1323f8fd9b1b

1 files changed, 12 insertions, 0 deletions

diff --git a/channels/chan_pjsip.c b/channels/chan_pjsip.c
index 98b4cf81c..82f716f08 100644
--- a/channels/chan_pjsip.c
+++ b/channels/chan_pjsip.c
@@ -2384,6 +2384,11 @@ static struct ast_custom_function media_offer_function = {
 	.write = pjsip_acf_media_offer_write
 };
 
+static struct ast_custom_function session_refresh_function = {
+	.name = "PJSIP_SEND_SESSION_REFRESH",
+	.write = pjsip_acf_session_refresh_write,
+};
+
 /*!
  * \brief Load the module
  *
@@ -2423,6 +2428,11 @@ static int load_module(void)
 		goto end;
 	}
 
+	if (ast_custom_function_register(&session_refresh_function)) {
+		ast_log(LOG_WARNING, "Unable to register PJSIP_SEND_SESSION_REFRESH dialplan function\n");
+		goto end;
+	}
+
 	if (ast_sip_session_register_supplement(&chan_pjsip_supplement)) {
 		ast_log(LOG_ERROR, "Unable to register PJSIP supplement\n");
 		goto end;
@@ -2479,6 +2489,7 @@ end:
 	pjsip_uids_onhold = NULL;
 	ast_custom_function_unregister(&media_offer_function);
 	ast_custom_function_unregister(&chan_pjsip_dial_contacts_function);
+	ast_custom_function_unregister(&session_refresh_function);
 	ast_channel_unregister(&chan_pjsip_tech);
 	ast_rtp_glue_unregister(&chan_pjsip_rtp_glue);
 
@@ -2500,6 +2511,7 @@ static int unload_module(void)
 
 	ast_custom_function_unregister(&media_offer_function);
 	ast_custom_function_unregister(&chan_pjsip_dial_contacts_function);
+	ast_custom_function_unregister(&session_refresh_function);
 
 	ast_channel_unregister(&chan_pjsip_tech);
 	ao2_ref(chan_pjsip_tech.capabilities, -1);