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Store computed reception time in the message struct so we don't rely on

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the message being emitted immediately.

Fix computation of reception time so it's more sensible (the block timestamp
is some time after reception of the _end_ of the block, not the start) - this
means that message-emission times are always later than message-reception
times in SBS output, which is a bit more sensible.

Use clock_gettime in preference to ftime.
This commit is contained in:
Oliver Jowett 2015-02-08 17:46:01 +00:00
parent 1584955080
commit 4e177c2d64
7 changed files with 76 additions and 31 deletions
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41
net_io.c
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@ -347,19 +347,19 @@ void modesSendRawOutput(struct modesMessage *mm) {
// The message structure mm->bFlags tells us what has been updated by this message
//
void modesSendSBSOutput(struct modesMessage *mm) {
char *p = prepareWrite(&Modes.sbs_out, 200);
uint32_t offset;
struct timeb epocTime_receive, epocTime_now;
char *p;
struct timespec now;
struct tm stTime_receive, stTime_now;
int msgType;
if (!p)
return;
// For now, suppress non-ICAO addresses
if (mm->addr & MODES_NON_ICAO_ADDRESS)
return;
p = prepareWrite(&Modes.sbs_out, 200);
if (!p)
return;
//
// SBS BS style output checked against the following reference
// http://www.homepages.mcb.net/bones/SBS/Article/Barebones42_Socket_Data.htm - seems comprehensive
@ -407,32 +407,19 @@ void modesSendSBSOutput(struct modesMessage *mm) {
p += sprintf(p, "MSG,%d,111,11111,%06X,111111,", msgType, mm->addr);
// Find current system time
ftime(&epocTime_now); // get the current system time & date
stTime_now = *localtime(&epocTime_now.time);
clock_gettime(CLOCK_REALTIME, &now);
localtime_r(&now.tv_sec, &stTime_now);
// Find message reception time
if (mm->timestampMsg && !mm->remote) { // Make sure the records' timestamp is valid before using it
epocTime_receive = Modes.stSystemTimeBlk; // This is the time of the start of the Block we're processing
offset = (int) (mm->timestampMsg - Modes.timestampBlk); // This is the time (in 12Mhz ticks) into the Block
offset = offset / 12000; // convert to milliseconds
epocTime_receive.millitm += offset; // add on the offset time to the Block start time
if (epocTime_receive.millitm > 999) { // if we've caused an overflow into the next second...
epocTime_receive.millitm -= 1000;
epocTime_receive.time ++; // ..correct the overflow
}
stTime_receive = *localtime(&epocTime_receive.time);
} else {
epocTime_receive = epocTime_now; // We don't have a usable reception time; use the current system time
stTime_receive = stTime_now;
}
localtime_r(&mm->sysTimestampMsg.tv_sec, &stTime_receive);
// Fields 7 & 8 are the message reception time and date
p += sprintf(p, "%04d/%02d/%02d,", (stTime_receive.tm_year+1900),(stTime_receive.tm_mon+1), stTime_receive.tm_mday);
p += sprintf(p, "%02d:%02d:%02d.%03d,", stTime_receive.tm_hour, stTime_receive.tm_min, stTime_receive.tm_sec, epocTime_receive.millitm);
p += sprintf(p, "%02d:%02d:%02d.%03u,", stTime_receive.tm_hour, stTime_receive.tm_min, stTime_receive.tm_sec, (unsigned) (mm->sysTimestampMsg.tv_nsec / 1000000U));
// Fields 9 & 10 are the current time and date
p += sprintf(p, "%04d/%02d/%02d,", (stTime_now.tm_year+1900),(stTime_now.tm_mon+1), stTime_now.tm_mday);
p += sprintf(p, "%02d:%02d:%02d.%03d", stTime_now.tm_hour, stTime_now.tm_min, stTime_now.tm_sec, epocTime_now.millitm);
p += sprintf(p, "%02d:%02d:%02d.%03u", stTime_now.tm_hour, stTime_now.tm_min, stTime_now.tm_sec, (unsigned) (now.tv_nsec / 1000000U));
// Field 11 is the callsign (if we have it)
if (mm->bFlags & MODES_ACFLAGS_CALLSIGN_VALID) {p += sprintf(p, ",%s", mm->flight);}
@ -574,6 +561,9 @@ int decodeBinMessage(struct client *c, char *p) {
if (0x1A == ch) {p++;}
}
// record reception time as the time we read it.
clock_gettime(CLOCK_REALTIME, &mm.sysTimestampMsg);
ch = *p++; // Grab the signal level
mm.signalLevel = ((unsigned char)ch / 256.0);
mm.signalLevel = mm.signalLevel * mm.signalLevel + 1e-5;
@ -697,6 +687,9 @@ int decodeHexMessage(struct client *c, char *hex) {
msg[j/2] = (high << 4) | low;
}
// record reception time as the time we read it.
clock_gettime(CLOCK_REALTIME, &mm.sysTimestampMsg);
if (l == (MODEAC_MSG_BYTES * 2)) { // ModeA or ModeC
Modes.stats_current.remote_received_modeac++;
decodeModeAMessage(&mm, ((msg[0] << 8) | msg[1]));