/*
* Generates a printable string from an abs_time_t structure, with
* granularity of whole seconds.
*
* @param[in] t - time for which a string is to be generated
* @param[out] buff - buffer into which string will be written
* @param[in] buff_len - length of caller-supplied buffer
*/
const char * abs_time_to_str_secs(abs_time_t t, char * buff, uint32_t buff_len)
{
struct timeval tv = TIME_GET_A(timeval, t);
struct tm bd_time;
struct tm * bd_result;
size_t strftime_result;
if (! buff || buff_len == 0) {
return NULL;
}
if (buff_len < DATE_AND_TIME_LENGTH_INCLUDING_NULL) {
buff[0] = 0;
return buff;
}
bd_result = localtime_r(&tv.tv_sec, &bd_time);
ASSERT(bd_result == &bd_time, "Bad return from localtime_r\n");
strftime_result = strftime(buff, DATE_AND_TIME_LENGTH_INCLUDING_NULL,
"%FT%T", &bd_time);
ASSERT(strftime_result == DATE_AND_TIME_LENGTH_INCLUDING_NULL-1,
"Bad result, %"PRIdPTR", from strftime\n", strftime_result);
return buff;
}
/*
* This callback is executed when the time to send the next
* receiver report is reached.
*/
UT_STATIC
void rtcp_receive_report_timeout_cb (const vqec_event_t * const evptr,
int32_t fd, int16_t event, void *arg)
{
rtp_session_t *p_sess = NULL;
rtp_member_t *local_member = NULL;
uint64_t time;
struct timeval tv;
if (!arg) {
rtcp_tmevt_log_err("%s %s", __FUNCTION__, s_arg_is_null);
/* ignore return {nothing to be done if stop fails} */
(void)vqec_event_stop(evptr);
return;
}
p_sess = (rtp_session_t *)arg;
local_member = p_sess->rtp_local_source;
if (!local_member) {
rtcp_tmevt_log_err("%s %s", __FUNCTION__, s_src_is_null);
/* ignore return nothing to be done if stop fails */
(void)vqec_event_stop(evptr);
return;
}
/* Update the timestamps */
time = TIME_GET_A(msec, get_sys_time());
local_member->rtp_timestamp = (uint32_t)time;
local_member->ntp_timestamp = abs_time_to_ntp(msec_to_abs_time(time));
MCALL(p_sess, rtp_update_stats, TRUE);
MCALL(p_sess, rtp_session_timeout_transmit_report);
timerclear(&tv);
rel_time_t diff = TIME_SUB_A_A(p_sess->next_send_ts,
msec_to_abs_time(time));
/* If the rel-time delta is -ive [lagging behind] use 0. */
if (TIME_CMP_R(lt, diff, REL_TIME_0)) {
diff = REL_TIME_0;
}
tv = TIME_GET_R(timeval, diff);
/* ignore return no recourse if start fails*/
(void)vqec_event_start(evptr, &tv);
}
const char * abs_time_to_str(abs_time_t t, char * buff, uint32_t buff_len)
{
struct timeval tv = TIME_GET_A(timeval, t);
struct tm bd_time;
struct tm * bd_result;
size_t strftime_result;
size_t sprintf_result;
#define DATE_AND_TIME_LENGTH_INCLUDING_NULL 20
#define LONG_DATE_AND_TIME_LENGTH_INCLUDING_NULL 40
#define FRAC_SEC_LENGTH_INCLUDING_NULL 8
#define TOTAL_LENGTH_INCLUDING_NULL \
(DATE_AND_TIME_LENGTH_INCLUDING_NULL + FRAC_SEC_LENGTH_INCLUDING_NULL - 1)
if (! buff || buff_len == 0)
return NULL;
if (buff_len < TOTAL_LENGTH_INCLUDING_NULL) {
buff[0] = 0;
return buff;
}
bd_result = localtime_r(&tv.tv_sec, &bd_time);
ASSERT(bd_result == &bd_time, "Bad return from localtime_r\n");
strftime_result = strftime(buff, DATE_AND_TIME_LENGTH_INCLUDING_NULL, "%F %T", &bd_time);
ASSERT(strftime_result == DATE_AND_TIME_LENGTH_INCLUDING_NULL-1,
"Bad result, %"PRIdPTR", from strftime\n", strftime_result);
sprintf_result = snprintf(&buff[DATE_AND_TIME_LENGTH_INCLUDING_NULL-1],
buff_len - DATE_AND_TIME_LENGTH_INCLUDING_NULL + 1,
".%06ld", tv.tv_usec);
ASSERT(sprintf_result == FRAC_SEC_LENGTH_INCLUDING_NULL-1,
"Bad result from sprintf\n");
return buff;
}
/******************************************************************************
* Adjust nll's state / predict a receive time for the given sample.
******************************************************************************/
void vqec_nll_adjust (vqec_nll_t * nll,
abs_time_t actual_time,
uint32_t pcr32,
rel_time_t est_rtp_delta,
boolean * disc,
abs_time_t * predicted_time)
{
rel_time_t time_delta = REL_TIME_0, correction = REL_TIME_0, arrival_error;
abs_time_t pred_arrival, prev_pred_base;
boolean reset_base;
if (!nll || !disc || !predicted_time) {
VQEC_DP_DEBUG(VQEC_DP_DEBUG_NLL, "adjust() invalid inputs %p/%p/%p\n",
nll, disc, predicted_time);
if (predicted_time) {
*predicted_time = get_sys_time();
}
return;
}
prev_pred_base = nll->pred_base;
if (*disc) {
nll->num_exp_disc++;
VQEC_DP_DEBUG(VQEC_DP_DEBUG_NLL,
"nll(%p) explicit discontinuity signaled: "
"actual_time %llu, pcr32 %u, est_rtp %llu\n", nll,
TIME_GET_A(msec, actual_time), pcr32,
TIME_GET_R(usec, est_rtp_delta));
}
/*
* The NLL operates in two modes: non-tracking and tracking. In
* non-tracking mode, the original receive times of the samples are
* unknown, and therefore, it just uses the sender RTP timestamps to
* determine the send time for packets. In tracking mode, the receive
* times of samples are known, except, e.g., when packets are received
* of order.
*/
switch (nll->mode) {
case VQEC_NLL_MODE_NONTRACKING: /* non-tracking mode */
if (!nll->got_first) {
/*
* if this is the 1st sample, set pred_base = actual_time if
* actual_time is non-0, otherwise set it to current time.
*/
nll->got_first = TRUE;
*disc = TRUE;
if (!IS_ABS_TIME_ZERO(actual_time)) {
nll->pred_base = actual_time;
} else {
nll->pred_base = get_sys_time();
}
} else { /* else-of !nll->got_first */
/*
* the code below considers the condition delta(rtp) >100 msecs
* an "Implicit discontinuity". Whenever there the code detects
* that the timing may be discontinuous, or the caller sets the
* discontinuity flag, "est_rtp_delta" is added to the previous
* value of pred_base. No limits are imposed on "est_rtp_delta".
*/
if (!*disc) {
time_delta = vqec_nll_rtp_delta(nll->pcr32_base, pcr32);
}
if (*disc ||
TIME_CMP_R(gt, time_delta,
MAX_NLL_DISCONTINUITY_THRESHOLD) ||
TIME_CMP_R(gt, TIME_NEG_R(time_delta),
MAX_NLL_DISCONTINUITY_THRESHOLD)) {
nll->pred_base =
TIME_ADD_A_R(nll->pred_base, est_rtp_delta);
if (!*disc) {
nll->num_imp_disc++; /* implicitly discontinuous oper */
*disc = TRUE;
VQEC_DP_DEBUG(VQEC_DP_DEBUG_NLL, "Implicit discontinuity : "
"nll(%p) pcr %u old_pcr %u pred_base %llu\n",
nll, pcr32, nll->pcr32_base,
TIME_GET_A(msec, nll->pred_base));
}
} else { /* else-of (*disc || TIME_CMP_R(... */
nll->pred_base = TIME_ADD_A_R(nll->pred_base, time_delta);
}
} /* !nll->got_first */
/*
* Protect backward fold in predicted time; the previous predicted
* time is selected if this condition is true.
*/
if (TIME_CMP_A(lt, nll->pred_base, prev_pred_base)) {
VQEC_DP_DEBUG(VQEC_DP_DEBUG_NLL, "Prediction in past: nll(%p)"
"new_base = %llu old_base = %llu pcr32 %u\n", nll,
TIME_GET_A(msec, nll->pred_base),
TIME_GET_A(msec, prev_pred_base),
nll->pcr32_base);
nll->pred_base = prev_pred_base;
nll->predict_in_past++;
}
nll->pcr32_base = pcr32;
*predicted_time = nll->pred_base;
if (nll->switch_to_tracking) { /* switch to tracking mode */
/*
* The rcc-repair burst and primary streams are received
* somewhat "asynchronously" of each other, i.e., the primary
* packets may be received at any epoch within the join latency
* window. Because of the bandwidth / join skew, in tracking
* mode the arrival error should be computed from the first
* primary packet's actual receive time. However, the time
* skew between the predicted receive time of the 1st primary,
* and it's actual receive time must be preserved, and added to
* all subsequent predictions in tracking mode. This value is
* termed "primary_offset". To switch to tracking mode it is
* *necessary* that a packet with non-0 actual time is provided.
* The error case is explicitly handled by using current predicted
* base as actual time causing primary_offset to be 0. This concept
* of time-shift is now an integral part of the nll, as is
* computed / cached implicitly when switching to tracking mode.
*/
abs_time_t act;
if (IS_ABS_TIME_ZERO(actual_time)) {
act = nll->pred_base;
} else {
act = actual_time;
}
nll->primary_offset =
TIME_SUB_A_A(nll->pred_base, act);
nll->pred_base =
nll->last_actual_time = act;
nll->switch_to_tracking = FALSE;
nll->mode = VQEC_NLL_MODE_TRACKING;
VQEC_DP_DEBUG(VQEC_DP_DEBUG_NLL,
"Switch to tracking : nll(%p) pred_base %llu "
"primary offset %lld actual time %llu \n", nll,
TIME_GET_A(msec, nll->pred_base),
TIME_GET_R(usec, nll->primary_offset),
TIME_GET_A(msec, actual_time));
}
break; /* done with non-tracking processing */
case VQEC_NLL_MODE_TRACKING: /* tracking mode */
if (!nll->got_first) {
/*
* if this is the 1st sample, set pred_base to actual_time +
* non-tracking-offset if actual time is non-0; otherwise, set it to
* current time + non-tracking-offset.
*/
nll->got_first = TRUE;
*disc = TRUE;
if (!IS_ABS_TIME_ZERO(actual_time)) {
nll->pred_base = actual_time;
} else {
nll->pred_base = get_sys_time();
}
} else { /* else-of !nll->got_first */
reset_base = FALSE;
if (!*disc) {
time_delta = vqec_nll_rtp_delta(nll->pcr32_base, pcr32);
/*
* We leave open the possibility of bounding this delta
* prior computing arrival error, and instead using the
* receive timestamp delta estimate (as for explicit disc)
* in an attempt to better predict implicit discontinuities.
* (this can also be done if the arrival error exceeded
* threshold, but there was no explicit discontinuity).
*/
} else {
/*
* In case of explicit discontinuity, approximate rtp delta from
* the receive timestamps of the current & previous sample, if
* they are both non-0. This approx is used only If the delta is
* < DISCONTINUITY_THRESHOLD msecs. Otherwise we'll reset
* the nll's pred_base / error average.
*/
if (!IS_ABS_TIME_ZERO(actual_time) &&
(!IS_ABS_TIME_ZERO(nll->last_actual_time))) {
time_delta = TIME_SUB_A_A(actual_time, nll->last_actual_time);
if (TIME_CMP_R(gt, time_delta,
MAX_NLL_DISCONTINUITY_THRESHOLD) ||
TIME_CMP_R(gt, TIME_NEG_R(time_delta),
MAX_NLL_DISCONTINUITY_THRESHOLD)) {
reset_base = TRUE;
} /* (TIME_CMP_R(gt...) */
} /* (!IS_ABS_TIME_ZERO()... */
} /* (!*disc) */
/*
* If we have a bounded estimate of the sender's time delta,
* compute arrival error, and ensure that it is bounded by
* +/- MAX_ARRIVAL_ERROR msecs. If not, we'll reset the nll's
* pred_base / error average. If no actual time is provided,
* we use, actual_time = pred_base + rtp_delta = pred_arrival.
*/
if (!reset_base) {
abs_time_t act;
if (IS_ABS_TIME_ZERO(actual_time)) {
act = TIME_ADD_A_R(nll->pred_base, time_delta);
} else {
act = actual_time;
}
pred_arrival = TIME_ADD_A_R(nll->pred_base, time_delta);
arrival_error = TIME_SUB_A_A(pred_arrival, act);
if (TIME_CMP_R(lt, arrival_error, MAX_ARRIVAL_ERROR)
&& TIME_CMP_R(lt, TIME_NEG_R(arrival_error),
MAX_ARRIVAL_ERROR)) {
correction = vqec_nll_update_error(nll, arrival_error);
nll->pred_base = TIME_ADD_A_R(pred_arrival, correction);
} else {
reset_base = TRUE; /* arrival error is out-of-bound */
}
}
if (reset_base) { /* explicit disc or excessive error */
if (!*disc) {
nll->num_imp_disc++; /* implicit discontinuous oper */
*disc = TRUE;
}
/*
* We must have an actual time provided for this particular
* case. If one is not provided, the last pred_base is used;
* a counter is incremented to keep track of such rather
* unlikely incidents.
*/
if (!IS_ABS_TIME_ZERO(actual_time)) {
nll->pred_base = actual_time;
} else {
nll->reset_base_no_act_time++;
VQEC_DP_DEBUG(VQEC_DP_DEBUG_NLL, "Reset base w/o act time "
"nll(%p)", nll);
}
nll->error_avg = REL_TIME_0; /* reset error average */
VQEC_DP_DEBUG(VQEC_DP_DEBUG_NLL, "Tracking mode discontinuity : "
"nll(%p) imp_disc %u exp_disc %u pcr %u old_pcr %u "
"pred_base %llu\n",
nll, nll->num_imp_disc, nll->num_exp_disc, pcr32,
nll->pcr32_base, TIME_GET_A(msec, nll->pred_base));
} /* end-of (reset_base) */
} /* end-of (!nll->got_first) */
/*
* Protect backward fold in predicted time; the previous predicted
* time is selected if this condition is true.
*/
if (TIME_CMP_A(lt, nll->pred_base, prev_pred_base)) {
VQEC_DP_DEBUG(VQEC_DP_DEBUG_NLL, "Prediction in past: nll(%p)"
"new_base = %llu old_base = %llu pcr32 %u\n", nll,
TIME_GET_A(msec, nll->pred_base),
TIME_GET_A(msec, prev_pred_base),
nll->pcr32_base);
nll->pred_base = prev_pred_base;
nll->predict_in_past++;
}
nll->pcr32_base = pcr32;
nll->last_actual_time = actual_time;
*predicted_time = TIME_ADD_A_R(nll->pred_base, nll->primary_offset);
break; /* done with tracking processing */
default: /* not reached */
VQEC_DP_ASSERT_FATAL(0, "nll fatal error");
break;
} /* end switch(mode) */
if (VQEC_DP_GET_DEBUG_FLAG(VQEC_DP_DEBUG_COLLECT_STATS)) {
nll->num_obs++;
}
VQEC_DP_DEBUG(VQEC_DP_DEBUG_NLL_ADJUST,
"Adjustment: nll(%p), base %llu, "
"pcr32 %u, correction %lld, cum err %lld\n", nll,
TIME_GET_A(msec, nll->pred_base), nll->pcr32_base,
TIME_GET_R(usec, correction), TIME_GET_R(usec, nll->error_avg));
}
