Optional HOLD/RETRIEVE signaling for PTMP TE when the bridge goes on and off hold.

Added the moh_signaling option to specify what to do when the channel's
bridged peer puts the ISDN channel on and off of hold.

Implemented as a FSM to control libpri ISDN signaling when the bridged
peer places the channel on and off of hold with the AST_CONTROL_HOLD and
AST_CONTROL_UNHOLD control frames.

JIRA SWP-2687
JIRA ABE-2691

Review:	https://reviewboard.asterisk.org/r/1063/


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@300212 65c4cc65-6c06-0410-ace0-fbb531ad65f3

CHANGES

@@ -15,23 +15,30 @@
 Asterisk Manager Interface
 --------------------------
  * PeerStatus now includes Address and Port.
+ * Added Hold events for when the remote party puts the call on and off hold
+   for chan_dahdi ISDN channels.
 
 Asterisk HTTP Server
 --------------------------
  * The HTTP Server can bind to IPv6 addresses.
 
 CLI Changes
------------
+--------------------------
  * New 'gtalk show settings' command showing the current settings loaded from
    gtalk.conf.
  * The 'logger reload' command now supports an optional argument, specifying an
    alternate configuration file to use.
 
 CDR
----
+--------------------------
  * The filter option in cdr_adaptive_odbc now supports negating the argument,
    thus allowing records which do NOT match the specified filter.
 
+libpri channel driver (chan_dahdi) DAHDI changes
+--------------------------
+ * Added moh_signaling option to specify what to do when the channel's bridged
+   peer puts the ISDN channel on hold.
+
 ------------------------------------------------------------------------------
 --- Functionality changes from Asterisk 1.6.2 to Asterisk 1.8 ----------------
 ------------------------------------------------------------------------------

UPGRADE.txt

@@ -7,7 +7,7 @@
 === versions listed below. These changes may require that
 === you modify your configuration files, dialplan or (in
 === some cases) source code if you have your own Asterisk
-=== modules or patches. These files also includes advance
+=== modules or patches. These files also include advance
 === notice of any functionality that has been marked as
 === 'deprecated' and may be removed in a future release,
 === along with the suggested replacement functionality.
@@ -30,6 +30,9 @@ Gtalk:
  - The default value for 'context' and 'parkinglots' in gtalk.conf has
    been changed to 'default', previously they were empty.
 
+chan_dahdi:
+ - The mohinterpret=passthrough setting is deprecated in favor of
+   moh_signaling=notify.
 
 ===========================================================
 ===========================================================

channels/chan_dahdi.c

@@ -12283,6 +12283,7 @@ static struct dahdi_pvt *mkintf(int channel, const struct dahdi_chan_conf *conf,
 						ast_copy_string(pris[span].pri.localprefix, conf->pri.pri.localprefix, sizeof(pris[span].pri.localprefix));
 						ast_copy_string(pris[span].pri.privateprefix, conf->pri.pri.privateprefix, sizeof(pris[span].pri.privateprefix));
 						ast_copy_string(pris[span].pri.unknownprefix, conf->pri.pri.unknownprefix, sizeof(pris[span].pri.unknownprefix));
+						pris[span].pri.moh_signaling = conf->pri.pri.moh_signaling;
 						pris[span].pri.resetinterval = conf->pri.pri.resetinterval;
 
 						for (x = 0; x < PRI_MAX_TIMERS; x++) {
@@ -17091,6 +17092,19 @@ static int process_dahdi(struct dahdi_chan_conf *confp, const char *cat, struct
 			} else if (!strcasecmp(v->name, "hold_disconnect_transfer")) {
 				confp->pri.pri.hold_disconnect_transfer = ast_true(v->value);
 #endif	/* defined(HAVE_PRI_CALL_HOLD) */
+			} else if (!strcasecmp(v->name, "moh_signaling")
+				|| !strcasecmp(v->name, "moh_signalling")) {
+				if (!strcasecmp(v->value, "moh")) {
+					confp->pri.pri.moh_signaling = SIG_PRI_MOH_SIGNALING_MOH;
+				} else if (!strcasecmp(v->value, "notify")) {
+					confp->pri.pri.moh_signaling = SIG_PRI_MOH_SIGNALING_NOTIFY;
+#if defined(HAVE_PRI_CALL_HOLD)
+				} else if (!strcasecmp(v->value, "hold")) {
+					confp->pri.pri.moh_signaling = SIG_PRI_MOH_SIGNALING_HOLD;
+#endif	/* defined(HAVE_PRI_CALL_HOLD) */
+				} else {
+					confp->pri.pri.moh_signaling = SIG_PRI_MOH_SIGNALING_MOH;
+				}
 #if defined(HAVE_PRI_CCSS)
 			} else if (!strcasecmp(v->name, "cc_ptmp_recall_mode")) {
 				if (!strcasecmp(v->value, "global")) {

channels/sig_pri.h

@@ -83,6 +83,67 @@ enum sig_pri_law {
 	SIG_PRI_ALAW
 };
 
+enum sig_pri_moh_signaling {
+	/*! Generate MOH to the remote party. */
+	SIG_PRI_MOH_SIGNALING_MOH,
+	/*! Send hold notification signaling to the remote party. */
+	SIG_PRI_MOH_SIGNALING_NOTIFY,
+#if defined(HAVE_PRI_CALL_HOLD)
+	/*! Use HOLD/RETRIEVE signaling to release the B channel while on hold. */
+	SIG_PRI_MOH_SIGNALING_HOLD,
+#endif	/* defined(HAVE_PRI_CALL_HOLD) */
+};
+
+enum sig_pri_moh_state {
+	/*! Bridged peer has not put us on hold. */
+	SIG_PRI_MOH_STATE_IDLE,
+	/*! Bridged peer has put us on hold and we were to notify the remote party. */
+	SIG_PRI_MOH_STATE_NOTIFY,
+	/*! Bridged peer has put us on hold and we were to play MOH or HOLD/RETRIEVE fallback. */
+	SIG_PRI_MOH_STATE_MOH,
+#if defined(HAVE_PRI_CALL_HOLD)
+	/*! Requesting to put channel on hold. */
+	SIG_PRI_MOH_STATE_HOLD_REQ,
+	/*! Trying to go on hold when bridged peer requested to unhold. */
+	SIG_PRI_MOH_STATE_PEND_UNHOLD,
+	/*! Channel is held. */
+	SIG_PRI_MOH_STATE_HOLD,
+	/*! Requesting to take channel out of hold. */
+	SIG_PRI_MOH_STATE_RETRIEVE_REQ,
+	/*! Trying to take channel out of hold when bridged peer requested to hold. */
+	SIG_PRI_MOH_STATE_PEND_HOLD,
+	/*! Failed to take the channel out of hold. No B channels were available? */
+	SIG_PRI_MOH_STATE_RETRIEVE_FAIL,
+#endif	/* defined(HAVE_PRI_CALL_HOLD) */
+
+	/*! Number of MOH states.  Must be last in enum. */
+	SIG_PRI_MOH_STATE_NUM
+};
+
+enum sig_pri_moh_event {
+	/*! Reset the MOH state machine. (Because of hangup.) */
+	SIG_PRI_MOH_EVENT_RESET,
+	/*! Bridged peer placed this channel on hold. */
+	SIG_PRI_MOH_EVENT_HOLD,
+	/*! Bridged peer took this channel off hold. */
+	SIG_PRI_MOH_EVENT_UNHOLD,
+#if defined(HAVE_PRI_CALL_HOLD)
+	/*! The hold request was successfully acknowledged. */
+	SIG_PRI_MOH_EVENT_HOLD_ACK,
+	/*! The hold request was rejected. */
+	SIG_PRI_MOH_EVENT_HOLD_REJ,
+	/*! The unhold request was successfully acknowledged. */
+	SIG_PRI_MOH_EVENT_RETRIEVE_ACK,
+	/*! The unhold request was rejected. */
+	SIG_PRI_MOH_EVENT_RETRIEVE_REJ,
+	/*! The remote party took this channel off hold. */
+	SIG_PRI_MOH_EVENT_REMOTE_RETRIEVE_ACK,
+#endif	/* defined(HAVE_PRI_CALL_HOLD) */
+
+	/*! Number of MOH events.  Must be last in enum. */
+	SIG_PRI_MOH_EVENT_NUM
+};
+
 struct sig_pri_span;
 
 struct sig_pri_callback {
@@ -201,6 +262,9 @@ struct sig_pri_chan {
 	/*! \brief Keypad digits that came in with the SETUP message. */
 	char keypad_digits[AST_MAX_EXTENSION];
 #endif	/* defined(HAVE_PRI_SETUP_KEYPAD) */
+	/*! Music class suggested with AST_CONTROL_HOLD. */
+	char moh_suggested[MAX_MUSICCLASS];
+	enum sig_pri_moh_state moh_state;
 
 #if defined(HAVE_PRI_AOC_EVENTS)
 	struct pri_subcmd_aoc_e aoc_e;
@@ -330,6 +394,7 @@ struct sig_pri_span {
 	char localprefix[20];					/*!< area access code + area code ('0'+area code for european dialplans) */
 	char privateprefix[20];					/*!< for private dialplans */
 	char unknownprefix[20];					/*!< for unknown dialplans */
+	enum sig_pri_moh_signaling moh_signaling;
 	long resetinterval;						/*!< Interval (in seconds) for resetting unused channels */
 #if defined(HAVE_PRI_MWI)
 	/*! \brief Active MWI mailboxes */

configs/chan_dahdi.conf.sample

@@ -902,15 +902,22 @@ pickupgroup=1
 ;
 ;faxbuffers=>6,full
 ;
+; This option specifies what to do when the channel's bridged peer puts the
+; ISDN channel on hold.  Settable per logical ISDN span.
+; moh:          Generate music-on-hold to the remote party.
+; notify:       Send hold notification signaling to the remote party.
+;               For ETSI PTP and ETSI PTMP NT links.
+;               (The notify setting deprecates the mohinterpret=passthrough setting.)
+; hold:         Use HOLD/RETRIEVE signaling to release the B channel while on hold.
+;               For ETSI PTMP TE links.
+;
+;moh_signaling=moh
+;
 ; This option specifies a preference for which music on hold class this channel
 ; should listen to when put on hold if the music class has not been set on the
 ; channel with Set(CHANNEL(musicclass)=whatever) in the dialplan, and the peer
 ; channel putting this one on hold did not suggest a music class.
 ;
-; If this option is set to "passthrough", then the hold message will always be
-; passed through as signalling instead of generating hold music locally. This
-; setting is only valid when used on a channel that uses digital signalling.
-;
 ; This option may be set globally or on a per-channel basis.
 ;
 ;mohinterpret=default