Calculate DF and size in decodeModeMessage

Allow the decodeModeMessage function to re-calculate msgtype and
msgbits. This makes the code a bit more portable by not requiring the
calling function to fill in these fields before the call.
This commit is contained in:
Malcolm Robb 2013-04-30 10:41:48 +01:00
parent c81498a0d0
commit 2e21367f85

View file

@ -1394,12 +1394,9 @@ void decodeModesMessage(struct modesMessage *mm, unsigned char *msg) {
memcpy(mm->msg, msg, MODES_LONG_MSG_BYTES);
msg = mm->msg;
// If we havn't already got it, get the message type ASAP as other operations depend on this
if (mm->msgbits == 0) {
mm->msgtype = msg[0] >> 3; // Downlink Format
mm->msgbits = modesMessageLenByType(mm->msgtype);
}
// Get the message type ASAP as other operations depend on this
mm->msgtype = msg[0] >> 3; // Downlink Format
mm->msgbits = modesMessageLenByType(mm->msgtype);
mm->errorbit = -1; // No errors fixed
mm->phase_corrected = 0;
mm->crc = modesChecksum(msg, mm->msgbits);
@ -2008,19 +2005,20 @@ void detectModeS(uint16_t *m, uint32_t mlen) {
// for the preamble samples, so round up and divide by 60.
sigStrength = (sigStrength + 29) / 60;
/* If we reached this point, and error is zero, we are very likely
* with a Mode S message in our hands, but it may still be broken
* and CRC may not be correct. This is handled by the next layer. */
if ((msglen) && (sigStrength > MODES_MSG_SQUELCH_LEVEL) && (errors <= MODES_MSG_ENCODER_ERRS) )
{
// When we reach this point, if error is small, and the signal strength is large enough
// we may have a Mode S message on our hands. It may still be broken and the CRC may not
// be correct, but this can be handled by the next layer.
if ( (msglen)
&& (sigStrength > MODES_MSG_SQUELCH_LEVEL)
&& (errors <= MODES_MSG_ENCODER_ERRS) ) {
struct modesMessage mm;
/* Decode the received message and update statistics */
// Set initial mm structure details
mm.timestampMsg = Modes.timestampBlk + (j*6);
sigStrength = (sigStrength + 0x7F) >> 8;
mm.signalLevel = ((sigStrength < 255) ? sigStrength : 255);
mm.msgbits = msglen;
mm.msgtype = msg[0] >> 3;
// Decode the received message
decodeModesMessage(&mm, msg);
/* Update statistics. */
@ -3009,7 +3007,6 @@ int decodeHexMessage(struct client *c) {
// Non timemarked internet data has indeterminate delay
mm.timestampMsg = -1;
mm.signalLevel = -1;
mm.msgbits = 0;
// Remove spaces on the left and on the right
while(l && isspace(hex[l-1])) {