From 98b8949f3b8149ef40e59b50f5d58fe5044a4432 Mon Sep 17 00:00:00 2001
From: "David E. Tiller" <3858971+dtiller@users.noreply.github.com>
Date: Wed, 30 Mar 2022 10:43:02 -0400
Subject: [PATCH] Slight fixes before switching to uint64_t and MSB processing.

---
 src/eotd.c        | 26 +++++++-------------------
 src/eotd.h        |  2 +-
 src/hdlc_rec.c    |  8 --------
 src/multi_modem.c |  4 ++--
 src/version.h     |  1 +
 5 files changed, 11 insertions(+), 30 deletions(-)

diff --git a/src/eotd.c b/src/eotd.c
index 60ce161..193edd9 100644
--- a/src/eotd.c
+++ b/src/eotd.c
@@ -23,20 +23,8 @@
  * File:	eotd.c
  *
  * Purpose:	Functions for processing received EOTD transmissions and
- *		converting to NMEA sentence representation.
+ *		converting to text format.
  *
- * References:	AIVDM/AIVDO protocol decoding by Eric S. Raymond
- *		https://gpsd.gitlab.io/gpsd/AIVDM.html
- *
- *		Sample recording with about 100 messages.  Test with "atest -B AIS xxx.wav"
- *		https://github.com/freerange/ais-on-sdr/wiki/example-data/long-beach-160-messages.wav
- *
- *		Useful on-line decoder for AIS NMEA sentences.
- *		https://www.aggsoft.com/ais-decoder.htm
- *
- * Future?	Add an interface to feed AIS data into aprs.fi.
- *		https://aprs.fi/page/ais_feeding
- *		
  *******************************************************************************/
 
 #include "direwolf.h"
@@ -53,21 +41,21 @@
 
 /*-------------------------------------------------------------------
  *
- * Convert EOTD binary block (from HDLC frame) to NMEA sentence. 
+ * Convert EOTD binary block (from HDLC frame) to text.
  *
  * In:	Pointer to EOTD binary block and number of bytes.
- * Out:	NMEA sentence.  Provide size to avoid string overflow.
+ * Out:	text.
  *
  *--------------------------------------------------------------------*/
 
-void eotd_to_nmea (unsigned char *eotd, int eotd_len, char *nmea, int nmea_size)
+void eotd_to_text (unsigned char *eotd, int eotd_len, char *text, int text_size)
 {
 	time_t now = time(NULL);
-	*nmea = '\0';
-	strcat(nmea, ctime(&now));
+	*text = '\0';
+	strcat(text, ctime(&now));
 	for (int i = 0; i < eotd_len; i++) {
 		char temp[32];
 		snprintf(temp, sizeof(temp), " %02x", eotd[i]);
-		strlcat(nmea, temp, nmea_size);
+		strlcat(text, temp, text_size);
 	}
 }
diff --git a/src/eotd.h b/src/eotd.h
index 64dba3a..3a55158 100644
--- a/src/eotd.h
+++ b/src/eotd.h
@@ -1 +1 @@
-void eotd_to_nmea (unsigned char *ais, int ais_len, char *nema, int nema_size);
+void eotd_to_text (unsigned char *ais, int ais_len, char *text, int text_size);
diff --git a/src/hdlc_rec.c b/src/hdlc_rec.c
index 93cb524..5a003ab 100644
--- a/src/hdlc_rec.c
+++ b/src/hdlc_rec.c
@@ -432,7 +432,6 @@ a good modem here and providing a result when it is received.
 #define EOTD_PREAMBLE_AND_BARKER_CODE	0x55555712
 #define HOTD_PREAMBLE_AND_BARKER_CODE	0x558f1129
 #define EOTD_MAX_LEN			8
-#undef DUMMY_BIT_HACK
 
 static void eotd_rec_bit (int chan, int subchan, int slice, int raw, int future_use)
 {
@@ -468,13 +467,6 @@ dw_printf("chan=%d subchan=%d slice=%d raw=%d\n", chan, subchan, slice, raw);
 	else if (H->eotd_gathering) {
 	  H->olen++;
 	
-#ifdef DUMMY_BIT_HACK
-	/* Hack to skip 'dummy' 64th bit */
-	  if (H->olen == 7 && H->frame_len == 7) {
-		H->eotd_acc <<= 1;
-		H->olen++;
-	  }
-#endif
 	  if (H->olen == 8) {
 	    H->olen = 0;
 	    char ch = H->eotd_acc & 0xff;
diff --git a/src/multi_modem.c b/src/multi_modem.c
index 86a59a7..432da29 100644
--- a/src/multi_modem.c
+++ b/src/multi_modem.c
@@ -345,9 +345,9 @@ void multi_modem_process_rec_frame (int chan, int subchan, int slice, unsigned c
 	}
 	else if (save_audio_config_p->achan[chan].modem_type == MODEM_EOTD) {
 	  char nmea[300];
-          eotd_to_nmea (fbuf, flen, nmea, sizeof(nmea));
+          eotd_to_text (fbuf, flen, nmea, sizeof(nmea));
 	  char monfmt[276];
-	  snprintf (monfmt, sizeof(monfmt), "EOTD>%s%1d%1d:{%c%c%s", APP_TOCALL, MAJOR_VERSION, MINOR_VERSION, USER_DEF_USER_ID, USER_DEF_TYPE_AIS, nmea);
+	  snprintf (monfmt, sizeof(monfmt), "EOTD>%s%1d%1d:{%c%c%s", APP_TOCALL, MAJOR_VERSION, MINOR_VERSION, USER_DEF_USER_ID, USER_DEF_TYPE_EOTD, nmea);
 	  pp = ax25_from_text (monfmt, 1);
 	}
 	else {
diff --git a/src/version.h b/src/version.h
index a09490c..feaa6c9 100644
--- a/src/version.h
+++ b/src/version.h
@@ -19,3 +19,4 @@
 
 #define USER_DEF_TYPE_AIS 'A'		// data type A for AIS NMEA sentence
 #define USER_DEF_TYPE_EAS 'E'		// data type E for EAS broadcasts
+#define USER_DEF_TYPE_EOTD 'T'		// data type T for 'T'rain broadcasts