Support setting and receiving Reverse Charging Indication over ISDN PRI.

This is a continuation of revision 885 to LibPRI (Capture and expose the Reverse
Charging Indication IE on ISDN PRI) which added the ability to get/set Reverse
Charging Indication in LibPRI.  This patch adds the ability to specify RCI on
the outbound leg of a PRI call from within Asterisk, by prefixing the dialed
number with a capital 'C' like:

...,Dial(DAHDI/g1/C4445556666)

And to read it off an inbound channel:

exten => s,1,Set(RCI=${CHANNEL(reversecharge)})

Thanks again to rmudgett for the thorough review.

(closes issue #13760)
Reported by: mrgabu

Review: https://reviewboard.asterisk.org/r/303/


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@204749 65c4cc65-6c06-0410-ace0-fbb531ad65f3

3 files changed, 23 insertions, 4 deletions

diff --git a/channels/chan_dahdi.c b/channels/chan_dahdi.c
index 7df0b592b..8a93673d0 100644
--- a/channels/chan_dahdi.c
+++ b/channels/chan_dahdi.c
@@ -5403,7 +5403,7 @@ static int dahdi_func_read(struct ast_channel *chan, const char *function, char
 {
 	struct dahdi_pvt *p = chan->tech_pvt;
 	int res = 0;
-	
+
 	if (!strcasecmp(data, "rxgain")) {
 		ast_mutex_lock(&p->lock);
 		snprintf(buf, len, "%f", p->rxgain);
@@ -5412,8 +5412,19 @@ static int dahdi_func_read(struct ast_channel *chan, const char *function, char
 		ast_mutex_lock(&p->lock);
 		snprintf(buf, len, "%f", p->txgain);
 		ast_mutex_unlock(&p->lock);
+#ifdef HAVE_PRI
+	} else if (!strcasecmp(data, "reversecharge")) {
+		ast_mutex_lock(&p->lock);
+		if (p->sig == SIG_PRI || p->sig == SIG_BRI || p->sig == SIG_BRI_PTMP) {
+			snprintf(buf, len, "%d", ((struct sig_pri_chan *) p->sig_pvt)->reverse_charging_indication);
+		} else {
+			*buf = '\0';
+			res = -1;
+		}
+		ast_mutex_unlock(&p->lock);
+#endif
 	} else {
-		ast_copy_string(buf, "", len);
+		*buf = '\0';
 		res = -1;
 	}
 
diff --git a/channels/sig_pri.c b/channels/sig_pri.c
index 464dde23a..aac40616e 100644
--- a/channels/sig_pri.c
+++ b/channels/sig_pri.c
@@ -1163,7 +1163,8 @@ static void *pri_dchannel(void *vpri)
 							pbx_builtin_setvar_helper(c, "CALLEDTON", calledtonstr);
 							if (e->ring.redirectingreason >= 0)
 								pbx_builtin_setvar_helper(c, "PRIREDIRECTREASON", redirectingreason2str(e->ring.redirectingreason));
-						
+							pri->pvts[chanpos]->reverse_charging_indication = e->ring.reversecharge;
+
 							sig_pri_lock_private(pri->pvts[chanpos]);
 							ast_mutex_lock(&pri->lock);
 
@@ -1208,7 +1209,8 @@ static void *pri_dchannel(void *vpri)
 
 								if (e->ring.redirectingreason >= 0)
 									pbx_builtin_setvar_helper(c, "PRIREDIRECTREASON", redirectingreason2str(e->ring.redirectingreason));
-							
+								pri->pvts[chanpos]->reverse_charging_indication = e->ring.reversecharge;
+
 								snprintf(calledtonstr, sizeof(calledtonstr)-1, "%d", e->ring.calledplan);
 								pbx_builtin_setvar_helper(c, "CALLEDTON", calledtonstr);
 
@@ -1888,6 +1890,11 @@ int sig_pri_call(struct sig_pri_chan *p, struct ast_channel *ast, char *rdest, i
 		case 'r':
 			pridialplan = PRI_NPI_RESERVED | (pridialplan & 0xf0);
 			break;
+#if defined(PRI_REVERSECHARGE_REQUESTED)
+		case 'C':
+			pri_sr_set_reversecharge(sr, PRI_REVERSECHARGE_REQUESTED);
+			break;
+#endif
 		default:
 			if (isalpha(c[p->stripmsd])) {
 				ast_log(LOG_WARNING, "Unrecognized pridialplan %s modifier: %c\n",
diff --git a/channels/sig_pri.h b/channels/sig_pri.h
index 80cfdd190..10f3618ac 100644
--- a/channels/sig_pri.h
+++ b/channels/sig_pri.h
@@ -162,6 +162,7 @@ struct sig_pri_chan {
 	struct sig_pri_callback *calls;
 	void *chan_pvt;
 	ast_mutex_t service_lock;						/*!< Mutex for service messages */
+	int reverse_charging_indication;
 };
 
 struct sig_pri_pri {