DTMF CallerID detection problems.

The code handling DTMF CallerID drops digits on long CallerID numbers and
may timeout waiting for the first ring with shorter numbers.

The DTMF emulation mode was not turned off when processing DTMF CallerID.
When the emulation code gets behind in processing the DTMF digits it can
skip a digit.

For shorter numbers, the timeout may have been too short.  I increased it
from 2 seconds to 4 seconds.  Four seconds is a typical time between rings
for many countries.

(closes issue #16460)
Reported by: sum
Patches:
      issue16460.patch uploaded by rmudgett (license 664)
      issue16460_v1.6.2.patch uploaded by rmudgett (license 664)
Tested by: sum, rmudgett

Review: https://reviewboard.asterisk.org/r/634/

JIRA SWP-562
JIRA AST-334
JIRA SWP-901


git-svn-id: http://svn.digium.com/svn/asterisk/branches/1.4@260195 f38db490-d61c-443f-a65b-d21fe96a405b

1 files changed, 22 insertions, 12 deletions

diff --git a/channels/chan_dahdi.c b/channels/chan_dahdi.c
index 28bdebe28..7d5ec489b 100644
--- a/channels/chan_dahdi.c
+++ b/channels/chan_dahdi.c
@@ -6589,14 +6589,25 @@ static void *ss_thread(void *data)
 			if (p->cid_signalling == CID_SIG_DTMF) {
 				int i = 0;
 				cs = NULL;
-				ast_log(LOG_DEBUG, "Receiving DTMF cid on "
-					"channel %s\n", chan->name);
+				ast_log(LOG_DEBUG, "Receiving DTMF cid on channel %s\n", chan->name);
 				dahdi_setlinear(p->subs[index].dfd, 0);
-				res = 2000;
+				/*
+				 * We are the only party interested in the Rx stream since
+				 * we have not answered yet.  We don't need or even want DTMF
+				 * emulation.  The DTMF digits can come so fast that emulation
+				 * can drop some of them.
+				 */
+				ast_set_flag(chan, AST_FLAG_END_DTMF_ONLY);
+				res = 4000;/* This is a typical OFF time between rings. */
 				for (;;) {
 					struct ast_frame *f;
 					res = ast_waitfor(chan, res);
 					if (res <= 0) {
+						/*
+						 * We do not need to restore the dahdi_setlinear()
+						 * or AST_FLAG_END_DTMF_ONLY flag settings since we
+						 * are hanging up the channel.
+						 */
 						ast_log(LOG_WARNING, "DTMFCID timed out waiting for ring. "
 							"Exiting simple switch\n");
 						ast_hangup(chan);
@@ -6606,22 +6617,24 @@ static void *ss_thread(void *data)
 					if (!f)
 						break;
 					if (f->frametype == AST_FRAME_DTMF) {
-						dtmfbuf[i++] = f->subclass;
+						if (i < ARRAY_LEN(dtmfbuf) - 1) {
+							dtmfbuf[i++] = f->subclass;
+						}
 						ast_log(LOG_DEBUG, "CID got digit '%c'\n", f->subclass);
-						res = 2000;
+						res = 4000;/* This is a typical OFF time between rings. */
 					}
 					ast_frfree(f);
 					if (chan->_state == AST_STATE_RING ||
 					    chan->_state == AST_STATE_RINGING) 
 						break; /* Got ring */
 				}
+				ast_clear_flag(chan, AST_FLAG_END_DTMF_ONLY);
 				dtmfbuf[i] = '\0';
 				dahdi_setlinear(p->subs[index].dfd, p->subs[index].linear);
 				/* Got cid and ring. */
 				ast_log(LOG_DEBUG, "CID got string '%s'\n", dtmfbuf);
 				callerid_get_dtmf(dtmfbuf, dtmfcid, &flags);
-				ast_log(LOG_DEBUG, "CID is '%s', flags %d\n", 
-					dtmfcid, flags);
+				ast_log(LOG_DEBUG, "CID is '%s', flags %d\n", dtmfcid, flags);
 				/* If first byte is NULL, we have no cid */
 				if (!ast_strlen_zero(dtmfcid)) 
 					number = dtmfcid;
@@ -6706,13 +6719,10 @@ static void *ss_thread(void *data)
 					if (p->cid_signalling == CID_SIG_V23_JP) {
 						res = dahdi_set_hook(p->subs[SUB_REAL].dfd, DAHDI_ONHOOK);
 						usleep(1);
-						res = 4000;
-					} else {
-
-						/* Finished with Caller*ID, now wait for a ring to make sure there really is a call coming */ 
-						res = 2000;
 					}
 
+					/* Finished with Caller*ID, now wait for a ring to make sure there really is a call coming */
+					res = 4000;/* This is a typical OFF time between rings. */
 					for (;;) {
 						struct ast_frame *f;
 						res = ast_waitfor(chan, res);