static void
process_pps(
peerT * const peer ,
json_ctx * const jctx ,
const l_fp * const rtime)
{
clockprocT * const pp = peer->procptr;
gpsd_unitT * const up = (gpsd_unitT *)pp->unitptr;
struct timespec ts;
errno = 0;
ts.tv_sec = (time_t)json_object_lookup_int(
jctx, 0, "clock_sec");
if (up->fl_nsec)
ts.tv_nsec = json_object_lookup_int(
jctx, 0, "clock_nsec");
else
ts.tv_nsec = json_object_lookup_int(
jctx, 0, "clock_musec") * 1000;
if (0 != errno)
goto fail;
up->pps_local = *rtime;
/* get fudged receive time */
up->pps_recvt = tspec_stamp_to_lfp(ts);
L_SUB(&up->pps_recvt, &up->pps_fudge);
/* map to next full second as reference time stamp */
up->pps_stamp = up->pps_recvt;
L_ADDUF(&up->pps_stamp, 0x80000000u);
up->pps_stamp.l_uf = 0;
pp->lastrec = up->pps_stamp;
DPRINTF(2, ("GPSD_JSON(%d): process_pps, stamp='%s', recvt='%s'\n",
up->unit,
gmprettydate(&up->pps_stamp),
gmprettydate(&up->pps_recvt)));
/* When we have a time pulse, clear the TPV flag: the
* PPS is only valid for the >NEXT< TPV value!
*/
up->fl_pps = -1;
up->fl_tpv = 0;
return;
fail:
DPRINTF(2, ("GPSD_JSON(%d): process_pps FAILED, nsec=%d stamp='%s', recvt='%s'\n",
up->unit, up->fl_nsec,
gmprettydate(&up->pps_stamp),
gmprettydate(&up->pps_recvt)));
up->tc_breply += 1;
}
void
test_ConstantDate(void) {
const u_int32 HALF = 2147483648UL;
l_fp e_time = {{3485080800UL}, HALF}; /* 2010-06-09 14:00:00.5 */
TEST_ASSERT_EQUAL_STRING("cfba1ce0.80000000 Wed, Jun 9 2010 14:00:00.500",
gmprettydate(&e_time));
return;
}
TEST_F(prettydateTest, ConstantDate) {
l_fp time = {3485080800UL, HALF}; // 2010-06-09 14:00:00.5
ASSERT_STREQ("cfba1ce0.80000000 Wed, Jun 9 2010 14:00:00.500", gmprettydate(&time));
}
static void
process_tpv(
peerT * const peer ,
json_ctx * const jctx ,
const l_fp * const rtime)
{
clockprocT * const pp = peer->procptr;
gpsd_unitT * const up = (gpsd_unitT *)pp->unitptr;
const char * gps_time;
int gps_mode;
double ept, epp, epx, epy, epv;
int xlog2;
gps_mode = (int)json_object_lookup_int_default(
jctx, 0, "mode", 0);
gps_time = json_object_lookup_string_default(
jctx, 0, "time", NULL);
if (gps_mode < 1 || NULL == gps_time) {
/* receiver has no fix; tell about and avoid stale data */
up->tc_breply += 1;
up->fl_tpv = 0;
up->fl_pps = 0;
return;
}
/* save last time code to clock data */
save_ltc(pp, gps_time);
/* convert clock and set resulting ref time */
if (convert_ascii_time(&up->tpv_stamp, gps_time)) {
DPRINTF(2, ("GPSD_JSON(%d): process_tpv, stamp='%s', recvt='%s' mode=%u\n",
up->unit,
gmprettydate(&up->tpv_stamp),
gmprettydate(&up->tpv_recvt),
gps_mode));
up->tpv_local = *rtime;
up->tpv_recvt = *rtime;/*TODO: hack until we get it remote from GPSD */
L_SUB(&up->tpv_recvt, &up->tpv_fudge);
up->fl_tpv = -1;
} else {
up->tc_btime += 1;
up->fl_tpv = 0;
}
/* Set the precision from the GPSD data
*
* Since EPT has some issues, we use EPT and a home-brewed error
* estimation base on a sphere derived from EPX/Y/V and the
* speed of light. Use the better one of those two.
*/
ept = json_object_lookup_float_default(jctx, 0, "ept", 1.0);
epx = json_object_lookup_float_default(jctx, 0, "epx", 1000.0);
epy = json_object_lookup_float_default(jctx, 0, "epy", 1000.0);
if (1 == gps_mode) {
/* 2d-fix: extend bounding rectangle to cuboid */
epv = max(epx, epy);
} else {
/* 3d-fix: get bounding cuboid */
epv = json_object_lookup_float_default(
jctx, 0, "epv", 1000.0);
}
/* get diameter of enclosing sphere of bounding cuboid as spatial
* error, then divide spatial error by speed of light to get
* another time error estimate. Add extra 100 meters as
* optimistic lower bound. Then use the better one of the two
* estimations.
*/
epp = 2.0 * sqrt(epx*epx + epy*epy + epv*epv);
epp = (epp + 100.0) / 299792458.0;
ept = min(ept, epp );
ept = min(ept, 0.5 );
ept = max(ept, 1.0-9);
ept = frexp(ept, &xlog2);
peer->precision = xlog2;
}
