diff --git a/channels/chan_iax2.c b/channels/chan_iax2.c
index ba785ce48774f2219699455eaae65d937ca844de..dad6707ba02e3c570b50dcb64e83b79280069364 100755
--- a/channels/chan_iax2.c
+++ b/channels/chan_iax2.c
@@ -318,6 +318,8 @@ static struct iax2_registry *registrations;
#define DEFAULT_TRUNKDATA 640 * 10 /* 40ms, uncompressed linear * 10 channels */
#define MAX_TRUNKDATA 640 * 200 /* 40ms, uncompressed linear * 200 channels */
+#define MAX_TIMESTAMP_SKEW 640
+
/* If we have more than this much excess real jitter buffer, srhink it. */
static int max_jitter_buffer = MAX_JITTER_BUFFER;
@@ -1113,17 +1115,8 @@ static int __do_deliver(void *data)
the IAX thread with the iaxsl lock held. */
struct iax_frame *fr = data;
fr->retrans = -1;
- if (iaxs[fr->callno] && !iaxs[fr->callno]->alreadygone) {
- if (fr->af.frametype == AST_FRAME_IAX &&
- fr->af.subclass == IAX_COMMAND_LAGRQ) {
- /* send a lag response to a lag request that has
- * gone through our jitter buffer */
- fr->af.subclass = IAX_COMMAND_LAGRP;
- iax2_send(iaxs[fr->callno], &fr->af, fr->ts, -1, 0, 0, 0);
- } else {
- iax2_queue_frame(fr->callno, &fr->af);
- }
- }
+ if (iaxs[fr->callno] && !iaxs[fr->callno]->alreadygone)
+ iax2_queue_frame(fr->callno, &fr->af);
/* Free our iax frame */
iax2_frame_free(fr);
/* And don't run again */
@@ -1606,9 +1599,11 @@ static int schedule_delivery(struct iax_frame *fr, int reallydeliver, int update
int ms,x;
int drops[MEMORY_SIZE];
int min, max=0, maxone=0,y,z, match;
+
/* ms is a measure of the "lateness" of the packet relative to the first
- packet we received, which always has a lateness of 1. Called by
- IAX thread, with iaxsl lock held. */
+ packet we received. Understand that "ms" can easily be -ve if lag improves
+ since call start.
+ Called by IAX thread, with iaxsl lock held. */
ms = calc_rxstamp(iaxs[fr->callno]) - fr->ts;
if (ms > 32767) {
@@ -1626,6 +1621,7 @@ static int schedule_delivery(struct iax_frame *fr, int reallydeliver, int update
fr->ts -= 65536;
}
+ /* delivery time is sender's sent timestamp converted back into absolute time according to our clock */
fr->af.delivery.tv_sec = iaxs[fr->callno]->rxcore.tv_sec;
fr->af.delivery.tv_usec = iaxs[fr->callno]->rxcore.tv_usec;
fr->af.delivery.tv_sec += fr->ts / 1000;
@@ -1635,7 +1631,6 @@ static int schedule_delivery(struct iax_frame *fr, int reallydeliver, int update
fr->af.delivery.tv_sec += 1;
}
-
/* Rotate our history queue of "lateness". Don't worry about those initial
zeros because the first entry will always be zero */
if (updatehistory) {
@@ -1708,10 +1703,16 @@ static int schedule_delivery(struct iax_frame *fr, int reallydeliver, int update
if (max > iaxs[fr->callno]->jitterbuffer)
iaxs[fr->callno]->jitterbuffer = max
/* + ((float)iaxs[fr->callno]->jitter) * 0.1 */;
-
+
+ /* If the caller just wanted us to update, return now */
+ if (!reallydeliver)
+ return 0;
if (option_debug)
- ast_log(LOG_DEBUG, "min = %d, max = %d, jb = %d, lateness = %d\n", min, max, iaxs[fr->callno]->jitterbuffer, ms);
+ /* Log jitter stats for possible offline analysis */
+ ast_log(LOG_DEBUG, "Jitter: call=%d ts=%d: min=%d max=%d jb=%d; lateness=%d; jitter=%d historic=%d\n",
+ fr->callno, fr->ts, min, max, iaxs[fr->callno]->jitterbuffer, ms,
+ iaxs[fr->callno]->jitter, iaxs[fr->callno]->historicjitter);
/* Subtract the lateness from our jitter buffer to know how long to wait
before sending our packet. */
@@ -1720,25 +1721,21 @@ static int schedule_delivery(struct iax_frame *fr, int reallydeliver, int update
if (!use_jitterbuffer)
ms = 0;
- /* If the caller just wanted us to update, return now */
- if (!reallydeliver)
- return 0;
-
if (ms < 1) {
- if (option_debug)
- ast_log(LOG_DEBUG, "Calculated ms is %d\n", ms);
/* Don't deliver it more than 4 ms late */
if ((ms > -4) || (fr->af.frametype != AST_FRAME_VOICE)) {
+ if (option_debug)
+ ast_log(LOG_DEBUG, "schedule_delivery: Delivering immediately (Calculated ms is %d)\n", ms);
__do_deliver(fr);
} else {
if (option_debug)
- ast_log(LOG_DEBUG, "Dropping voice packet since %d ms is, too old\n", ms);
+ ast_log(LOG_DEBUG, "schedule_delivery: Dropping voice packet since %d ms is too old\n", ms);
/* Free our iax frame */
iax2_frame_free(fr);
}
} else {
if (option_debug)
- ast_log(LOG_DEBUG, "Scheduling delivery in %d ms\n", ms);
+ ast_log(LOG_DEBUG, "schedule_delivery: Scheduling delivery in %d ms\n", ms);
fr->retrans = ast_sched_add(sched, ms, do_deliver, fr);
}
return 0;
@@ -2588,7 +2585,7 @@ static unsigned int calc_txpeerstamp(struct iax2_trunk_peer *tpeer, int sampms,
ms = (tv->tv_sec - tpeer->txtrunktime.tv_sec) * 1000 + (tv->tv_usec - tpeer->txtrunktime.tv_usec) / 1000;
/* Predict from last value */
pred = tpeer->lastsent + sampms;
- if (abs(ms - pred) < 640)
+ if (abs(ms - pred) < MAX_TIMESTAMP_SKEW)
ms = pred;
/* We never send the same timestamp twice, so fudge a little if we must */
@@ -2621,6 +2618,13 @@ static unsigned int calc_timestamp(struct chan_iax2_pvt *p, unsigned int ts, str
int voice = 0;
int genuine = 0;
struct timeval *delivery = NULL;
+
+ /* What sort of frame do we have?: voice is self-explanatory
+ "genuine" means an IAX frame - things like LAGRQ/RP, PING/PONG, ACK
+ non-genuine frames are CONTROL frames [ringing etc], DTMF
+ The "genuine" distinction is needed because genuine frames must get a clock-based timestamp,
+ the others need a timestamp slaved to the voice frames so that they go in sequence
+ */
if (f) {
if (f->frametype == AST_FRAME_VOICE) {
voice = 1;
@@ -2637,6 +2641,7 @@ static unsigned int calc_timestamp(struct chan_iax2_pvt *p, unsigned int ts, str
/* If the timestamp is specified, just send it as is */
if (ts)
return ts;
+ /* If we have a time that the frame arrived, always use it to make our timestamp */
if (delivery && (delivery->tv_sec || delivery->tv_usec)) {
ms = (delivery->tv_sec - p->offset.tv_sec) * 1000 + (delivery->tv_usec - p->offset.tv_usec) / 1000;
} else {
@@ -2646,19 +2651,24 @@ static unsigned int calc_timestamp(struct chan_iax2_pvt *p, unsigned int ts, str
ms = 0;
if (voice) {
/* On a voice frame, use predicted values if appropriate */
- if (abs(ms - p->nextpred) <= 640) {
- if (!p->nextpred)
- p->nextpred = f->samples / 8;
+ if (abs(ms - p->nextpred) <= MAX_TIMESTAMP_SKEW) {
+ if (!p->nextpred) {
+ p->nextpred = ms; /*f->samples / 8;*/
+ if (p->nextpred <= p->lastsent)
+ p->nextpred = p->lastsent + 3;
+ }
ms = p->nextpred;
} else
p->nextpred = ms;
} else {
- /* On a dataframe, use last value + 3 (to accomodate jitter buffer shrinkign) if appropriate unless
+ /* On a dataframe, use last value + 3 (to accomodate jitter buffer shrinking) if appropriate unless
it's a genuine frame */
if (genuine) {
+ /* genuine (IAX LAGRQ etc) must keep their clock-based stamps */
if (ms <= p->lastsent)
ms = p->lastsent + 3;
- } else if (abs(ms - p->lastsent) <= 640) {
+ } else if (abs(ms - p->lastsent) <= MAX_TIMESTAMP_SKEW) {
+ /* non-genuine frames (!?) (DTMF, CONTROL) should be pulled into the predicted stream stamps */
ms = p->lastsent + 3;
}
}
@@ -4955,10 +4965,8 @@ retryowner:
/* Handle the IAX pseudo frame itself */
if (option_debug)
ast_log(LOG_DEBUG, "IAX subclass %d received\n", f.subclass);
- /* Go through the motions of delivering the packet without actually doing so,
- unless this is a lag request since it will be done for real */
- if (f.subclass != IAX_COMMAND_LAGRQ)
- schedule_delivery(&fr, 0, updatehistory);
+ /* Go through the motions of delivering the packet without actually doing so */
+ schedule_delivery(&fr, 0, updatehistory);
switch(f.subclass) {
case IAX_COMMAND_ACK:
/* Do nothing */
@@ -5248,15 +5256,18 @@ retryowner2:
f.samples = 0;
iax_frame_wrap(&fr, &f);
if(f.subclass == IAX_COMMAND_LAGRQ) {
- /* A little strange -- We have to actually go through the motions of
- delivering the packet. In the very last step, it will be properly
- handled by do_deliver */
- schedule_delivery(iaxfrdup2(&fr), 1, updatehistory);
+ /* Received a LAGRQ - echo back a LAGRP */
+ fr.af.subclass = IAX_COMMAND_LAGRP;
+ iax2_send(iaxs[fr.callno], &fr.af, fr.ts, -1, 0, 0, 0);
} else {
+ /* Received LAGRP in response to our LAGRQ */
unsigned int ts;
/* This is a reply we've been given, actually measure the difference */
ts = calc_timestamp(iaxs[fr.callno], 0, &fr.af);
iaxs[fr.callno]->lag = ts - fr.ts;
+ if (option_debug)
+ ast_log(LOG_DEBUG, "Peer %s lag measured as %dms\n",
+ inet_ntoa(iaxs[fr.callno]->addr.sin_addr), iaxs[fr.callno]->lag);
}
#ifdef BRIDGE_OPTIMIZATION
}