decode_aprs.c

//
//    This file is part of Dire Wolf, an amateur radio packet TNC.
//
//    Copyright (C) 2011, 2012, 2013, 2014, 2015, 2017, 2022  John Langner, WB2OSZ
//
//    This program is free software: you can redistribute it and/or modify
//    it under the terms of the GNU General Public License as published by
//    the Free Software Foundation, either version 2 of the License, or
//    (at your option) any later version.
//
//    This program is distributed in the hope that it will be useful,
//    but WITHOUT ANY WARRANTY; without even the implied warranty of
//    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
//    GNU General Public License for more details.
//
//    You should have received a copy of the GNU General Public License
//    along with this program.  If not, see <http://www.gnu.org/licenses/>.
//


/*------------------------------------------------------------------
 *
 * File:	decode_aprs.c
 *
 * Purpose:	Decode the information part of APRS frame.
 *
 * Description: Present the packet contents in human readable format.
 *		This is a fairly complete implementation with error messages
 *		pointing out various specification violations.
 *
 * Assumptions:	ax25_from_frame() has been called to 
 *		separate the header and information.
 *
 *------------------------------------------------------------------*/

#include "direwolf.h"

#include <stdio.h>
#include <time.h>
#include <assert.h>
#include <stdlib.h>	/* for atof */
#include <string.h>	/* for strtok */

#include <math.h>	/* for pow */
#include <ctype.h>	/* for isdigit */
#include <fcntl.h>

#include "regex.h"

#include "ax25_pad.h"
#include "textcolor.h"
#include "symbols.h"
#include "latlong.h"
#include "dwgpsnmea.h"
#include "decode_aprs.h"
#include "telemetry.h"
#include "ais.h"


#define TRUE 1
#define FALSE 0



/* Position & symbol fields common to several message formats. */

typedef struct {
	  char lat[8];
	  char sym_table_id;		/* / \ 0-9 A-Z */
	  char lon[9];
	  char symbol_code;
	} position_t;

typedef struct {
	  char sym_table_id;		/* / \ a-j A-Z */
					/* "The presence of the leading Symbol Table Identifier */
					/* instead of a digit indicates that this is a compressed */
					/* Position Report and not a normal lat/long report." */
					/* "a-j" is not a typographical error. */
					/* The first 10 lower case letters represent the overlay */
					/* characters of 0-9 in the compressed format. */

	  char y[4];			/* Compressed Latitude. */
	  char x[4];			/* Compressed Longitude. */
	  char symbol_code;
	  char c;			/* Course/speed or altitude. */
	  char s;
	  char t	;		/* Compression type. */
	} compressed_position_t;


/* Range of digits for Base 91 representation. */

#define B91_MIN '!'
#define B91_MAX '{'
#define isdigit91(c) ((c) >= B91_MIN && (c) <= B91_MAX)


//static void print_decoded (decode_aprs_t *A);
static void aprs_ll_pos (decode_aprs_t *A, unsigned char *, int);
static void aprs_ll_pos_time (decode_aprs_t *A, unsigned char *, int);
static void aprs_raw_nmea (decode_aprs_t *A, unsigned char *, int);
static void aprs_mic_e (decode_aprs_t *A, packet_t, unsigned char *, int);
//static void aprs_compressed_pos (decode_aprs_t *A, unsigned char *, int);
static void aprs_message (decode_aprs_t *A, unsigned char *, int, int quiet);
static void aprs_object (decode_aprs_t *A, unsigned char *, int);
static void aprs_item (decode_aprs_t *A, unsigned char *, int);
static void aprs_station_capabilities (decode_aprs_t *A, char *, int);
static void aprs_status_report (decode_aprs_t *A, char *, int);
static void aprs_general_query (decode_aprs_t *A, char *, int, int quiet);
static void aprs_directed_station_query (decode_aprs_t *A, char *addressee, char *query, int quiet);
static void aprs_telemetry (decode_aprs_t *A, char *info, int info_len, int quiet);
static void aprs_user_defined (decode_aprs_t *A, char *, int);
static void aprs_raw_touch_tone (decode_aprs_t *A, char *, int);
static void aprs_morse_code (decode_aprs_t *A, char *, int);
static void aprs_positionless_weather_report (decode_aprs_t *A, unsigned char *, int);
static void weather_data (decode_aprs_t *A, char *wdata, int wind_prefix);
static void aprs_ultimeter (decode_aprs_t *A, char *, int);
static void decode_position (decode_aprs_t *A, position_t *ppos);
static void decode_compressed_position (decode_aprs_t *A, compressed_position_t *ppos);
static double get_latitude_8 (char *p, int quiet);
static double get_longitude_9 (char *p, int quiet);
static time_t get_timestamp (decode_aprs_t *A, char *p);
static int get_maidenhead (decode_aprs_t *A, char *p);
static int data_extension_comment (decode_aprs_t *A, char *pdext);
static void decode_tocall (decode_aprs_t *A, char *dest);
//static void get_symbol (decode_aprs_t *A, char dti, char *src, char *dest);
static void process_comment (decode_aprs_t *A, char *pstart, int clen);




/*------------------------------------------------------------------
 *
 * Function:	decode_aprs
 *
 * Purpose:	Split APRS packet into separate properties that it contains.
 *
 * Inputs:	pp	- APRS packet object.
 *
 *		quiet	- Suppress error messages.
 *
 *		third_party_src - Specify when parsing a third party header.
 *			(decode_aprs is called recursively.)
 *			This is mostly found when an IGate transmits a message
 *			that came via APRS-IS.
 *			NULL when not third party payload.
 *
 * Outputs:	A->	g_symbol_table, g_symbol_code,
 *			g_lat, g_lon, 
 *			g_speed_mph, g_course, g_altitude_ft,
 *			g_comment
 *			... and many others...
 *
 * Major Revisions: 1.1	Reorganized so parts are returned in a structure.
 *			Print function is now called separately.
 *
 *------------------------------------------------------------------*/

void decode_aprs (decode_aprs_t *A, packet_t pp, int quiet, char *third_party_src)
{
	//dw_printf ("DEBUG decode_aprs quiet=%d, third_party=%p\n", quiet, third_party_src);

	unsigned char *pinfo;
	int info_len;


  	info_len = ax25_get_info (pp, &pinfo);

	//dw_printf ("DEBUG decode_aprs info=\"%s\"\n", pinfo);

	memset (A, 0, sizeof (*A));

	A->g_quiet = quiet;

	if (isprint(*pinfo)) {
	  snprintf (A->g_data_type_desc, sizeof(A->g_data_type_desc), "ERROR!!!  Unknown APRS Data Type Indicator \"%c\"", *pinfo);
	}
	else {
	  snprintf (A->g_data_type_desc, sizeof(A->g_data_type_desc), "ERROR!!!  Unknown APRS Data Type Indicator: unprintable 0x%02x", *pinfo);
	}

	A->g_symbol_table = '/';	/* Default to primary table. */
	A->g_symbol_code = ' ';		/* What should we have for default symbol? */

	A->g_lat = G_UNKNOWN;
	A->g_lon = G_UNKNOWN;

	A->g_speed_mph = G_UNKNOWN;
	A->g_course = G_UNKNOWN;

	A->g_power = G_UNKNOWN;
	A->g_height = G_UNKNOWN;
	A->g_gain = G_UNKNOWN;

	A->g_range = G_UNKNOWN;
	A->g_altitude_ft = G_UNKNOWN;
	A->g_freq = G_UNKNOWN;
	A->g_tone = G_UNKNOWN;
	A->g_dcs = G_UNKNOWN;
	A->g_offset = G_UNKNOWN;

	A->g_footprint_lat = G_UNKNOWN;
	A->g_footprint_lon = G_UNKNOWN;
	A->g_footprint_radius = G_UNKNOWN;

// TODO: Complain if obsolete WIDE or RELAY is found in via path.

// TODO: complain if unused WIDEn is see in path.
// There is a report of UIDIGI decrementing ssid 1 to 0 and not marking it used.
// http://lists.tapr.org/pipermail/aprssig_lists.tapr.org/2022-May/049397.html

// TODO: Complain if used digi is found after unused.  Should never happen.


// If third-party header, try to decode just the payload.

	if (*pinfo == '}') {

	  //dw_printf ("DEBUG decode_aprs recursively process third party header\n");

	  // This must not be strict because the addresses in third party payload doesn't
	  // need to adhere to the AX.25 address format (i.e. 6 upper case alphanumeric.)
	  // SSID can be 2 alphanumeric characters.
	  // Addresses can include lower case, e.g. q construct.

	  // e.g.  WR2X-2>APRS,WA1PLE-13*:}
	  //		K1BOS-B>APOSB,TCPIP,WR2X-2*:@122015z4221.42ND07111.93W&/A=000000SharkRF openSPOT3 MMDVM446.025 MA/SW

	  packet_t pp_payload = ax25_from_text ((char*)pinfo+1, 0);
	  if (pp_payload != NULL) {
	    char payload_src[AX25_MAX_ADDR_LEN];
	    memset(payload_src, 0, sizeof(payload_src));
	    memcpy(payload_src, (char*)pinfo+1, sizeof(payload_src)-1);
	    char *q = strchr(payload_src, '>');
	    if (q != NULL) *q = '\0';
	    decode_aprs (A, pp_payload, quiet, payload_src);	// 1 means used recursively
	    ax25_delete (pp_payload);
	    return;
	  }
	  else {
	    strlcpy (A->g_data_type_desc, "Third Party Header: Unable to parse payload.", sizeof(A->g_data_type_desc));
	    ax25_get_addr_with_ssid (pp, AX25_SOURCE, A->g_src);
	    ax25_get_addr_with_ssid (pp, AX25_DESTINATION, A->g_dest);
	  }
	}

/*
 * Extract source and destination including the SSID.
 */
	if (third_party_src != NULL) {
	    strlcpy (A->g_src, third_party_src, sizeof(A->g_src));
	}
	else {
	    ax25_get_addr_with_ssid (pp, AX25_SOURCE, A->g_src);
	}
	ax25_get_addr_with_ssid (pp, AX25_DESTINATION, A->g_dest);

	//dw_printf ("DEBUG decode_aprs source=%s, dest=%s\n", A->g_src, A->g_dest);


/*
 * Report error if the information part contains a nul character.
 * There are two known cases where this can happen.
 *
 *  - The Kenwood TM-D710A sometimes sends packets like this:
 *
 * 	VA3AJ-9>T2QU6X,VE3WRC,WIDE1,K8UNS,WIDE2*:4P<0x00><0x0f>4T<0x00><0x0f>4X<0x00><0x0f>4\<0x00>`nW<0x1f>oS8>/]"6M}driving fast= 
 * 	K4JH-9>S5UQ6X,WR4AGC-3*,WIDE1*:4P<0x00><0x0f>4T<0x00><0x0f>4X<0x00><0x0f>4\<0x00>`jP}l"&>/]"47}QRV from the EV =
 *
 *     Notice that the data type indicator of "4" is not valid.  If we remove
 *     4P<0x00><0x0f>4T<0x00><0x0f>4X<0x00><0x0f>4\<0x00>   we are left with a good MIC-E format.
 *     This same thing has been observed from others and is intermittent.
 *
 *  - AGW Tracker can send UTF-16 if an option is selected.  This can introduce nul bytes.
 *    This is wrong, it should be using UTF-8.
 */

	if ( ( ! A->g_quiet ) && ( (int)strlen((char*)pinfo) != info_len) ) {

	  text_color_set(DW_COLOR_ERROR);
	  dw_printf("'nul' character found in Information part.  This should never happen with APRS.\n");
	  dw_printf("If this is meant to be APRS, %s is transmitting with defective software.\n", A->g_src);

	  if (strcmp((char*)pinfo, "4P") == 0) {
	    dw_printf("The TM-D710 will do this intermittently.  A firmware upgrade is needed to fix it.\n");
	  }
	}

/*
 * Application might be in the destination field for most message types.
 * MIC-E format has part of location in the destination field.
 */

	switch (*pinfo) {	/* "DTI" data type identifier. */

	  case '\'':		/* Old Mic-E Data */
	  case '`':		/* Current Mic-E Data */
	    break;

	  default:
	    decode_tocall (A, A->g_dest);
	    break;
	}

	switch (*pinfo) {	/* "DTI" data type identifier. */

	    case '!':		/* Position without timestamp (no APRS messaging). */
				/* or Ultimeter 2000 WX Station */

	    case '=':		/* Position without timestamp (with APRS messaging). */

	      if (strncmp((char*)pinfo, "!!", 2) == 0)
	      {
		aprs_ultimeter (A, (char*)pinfo, info_len);		// TODO: produce obsolete error.
	      }
	      else
	      {	     
	        aprs_ll_pos (A, pinfo, info_len);
	      }
	      break;


	    //case '#':		/* Peet Bros U-II Weather station */		// TODO: produce obsolete error.
	    //case '*':		/* Peet Bros U-II Weather station */
	      //break;
		
	    case '$':		/* Raw GPS data or Ultimeter 2000 */
		
	      if (strncmp((char*)pinfo, "$ULTW", 5) == 0)
	      {
		aprs_ultimeter (A, (char*)pinfo, info_len);		// TODO: produce obsolete error.
	      }
	      else
	      {
	        aprs_raw_nmea (A, pinfo, info_len);
	      }
	      break;

	    case '\'':		/* Old Mic-E Data (but Current data for TM-D700) */
	    case '`':		/* Current Mic-E Data (not used in TM-D700) */

	      aprs_mic_e (A, pp, pinfo, info_len);
	      break;

	    case ')':		/* Item. */

	      aprs_item (A, pinfo, info_len);
	      break;
		
	    case '/':		/* Position with timestamp (no APRS messaging) */
	    case '@':		/* Position with timestamp (with APRS messaging) */

	      aprs_ll_pos_time (A, pinfo, info_len);
	      break;


	    case ':':		/* "Message" (special APRS meaning): for one person, a group, or a bulletin. */
				/* Directed Station Query */
				/* Telemetry metadata. */

	      aprs_message (A, pinfo, info_len, quiet);
	      break;

	    case ';':		/* Object */

	      aprs_object (A, pinfo, info_len);
	      break;

	    case '<':		/* Station Capabilities */

	      aprs_station_capabilities (A, (char*)pinfo, info_len);
	      break;

	    case '>':		/* Status Report */

	      aprs_status_report (A, (char*)pinfo, info_len);
	      break;

	    
	    case '?':		/* General Query */

	      aprs_general_query (A, (char*)pinfo, info_len, quiet);
	      break;
		
	    case 'T':		/* Telemetry */

	      aprs_telemetry (A, (char*)pinfo, info_len, quiet);
	      break;

	    case '_':		/* Positionless Weather Report */

	      aprs_positionless_weather_report (A, pinfo, info_len);
	      break;

	    case '{':		/* user defined data */

	      aprs_user_defined (A, (char*)pinfo, info_len);
	      break;

	    case 't':		/* Raw touch tone data - NOT PART OF STANDARD */
				/* Used to convey raw touch tone sequences to */
				/* to an application that might want to interpret them. */
				/* Might move into user defined data, above. */

	      aprs_raw_touch_tone (A, (char*)pinfo, info_len);
	      break;

	    case 'm':		/* Morse Code data - NOT PART OF STANDARD */
				/* Used by APRStt gateway to put audible responses */
				/* into the transmit queue.  Could potentially find */
				/* other uses such as CW ID for station. */
				/* Might move into user defined data, above. */

	      aprs_morse_code (A, (char*)pinfo, info_len);
	      break;

	    //case '}':		/* third party header */

	      // was already caught earlier.

	    //case '\r':		/* CR or LF? */
	    //case '\n':
	
	      //break;

	    default:

	      break;
	}


/*
 * Priority order for determining the symbol is:
 *	- Information part, where appropriate.  Already done above.
 *	- Destination field starting with GPS, SPC, or SYM.
 *	- Source SSID - Confusing to most people.  Even I forgot about it when
 *		someone questioned where the symbol came from.  It's in the APRS
 *		protocol spec, end of Chapter 20.
 */

	if (A->g_symbol_table == ' ' || A->g_symbol_code == ' ') {

	  // A symbol on a "message" makes no sense and confuses people.
	  // Third party too.  Set from the payload.
	  // Maybe eliminate for a couple others.

	  //dw_printf ("DEBUG decode_aprs@end1 third_party=%d, symbol_table=%c, symbol_code=%c, *pinfo=%c\n", third_party, A->g_symbol_table, A->g_symbol_code, *pinfo);

	  if (*pinfo != ':' && *pinfo != '}') {
	    symbols_from_dest_or_src (*pinfo, A->g_src, A->g_dest, &A->g_symbol_table, &A->g_symbol_code);
	  }

	  //dw_printf ("DEBUG decode_aprs@end2 third_party=%d, symbol_table=%c, symbol_code=%c, *pinfo=%c\n", third_party, A->g_symbol_table, A->g_symbol_code, *pinfo);
	}
	
} /* end decode_aprs */


void decode_aprs_print (decode_aprs_t *A) {

	char stemp[500];
	double absll;
	char news;
	int deg;
	double min;
	char s_lat[30];
	char s_lon[30];
	int n;

/*
 * First line has:
 * - packet type
 * - object name
 * - symbol
 * - manufacturer/application
 * - mic-e status
 * - power/height/gain, range
 */
	strlcpy (stemp, A->g_data_type_desc, sizeof(stemp));

	//dw_printf ("DEBUG decode_aprs_print stemp1=%s\n", stemp);

	if (strlen(A->g_name) > 0) {
	  strlcat (stemp, ", \"", sizeof(stemp));
	  strlcat (stemp, A->g_name, sizeof(stemp));
	  strlcat (stemp, "\"", sizeof(stemp));
	}

	//dw_printf ("DEBUG decode_aprs_print stemp2=%s\n", stemp);

	//dw_printf ("DEBUG decode_aprs_print symbol_code=%c=0x%02x\n", A->g_symbol_code, A->g_symbol_code);

	if (A->g_symbol_code != ' ') {
	  char symbol_description[100];
	  symbols_get_description (A->g_symbol_table, A->g_symbol_code, symbol_description, sizeof(symbol_description));
	
	  //dw_printf ("DEBUG decode_aprs_print symbol_description_description=%s\n", symbol_description);

	  strlcat (stemp, ", ", sizeof(stemp));
	  strlcat (stemp, symbol_description, sizeof(stemp));
	}

	//dw_printf ("DEBUG decode_aprs_print stemp3=%s mfr=%s\n", stemp, A->g_mfr);

	if (strlen(A->g_mfr) > 0) {
	  if (strcmp(A->g_dest, "APRS") == 0  ||  strcmp(A->g_dest, "BEACON") == 0) {
	    strlcat (stemp, "\nUse of \"", sizeof(stemp));
	    strlcat (stemp, A->g_dest, sizeof(stemp));
	    strlcat (stemp, "\" in the destination field is obsolete.", sizeof(stemp));
	    strlcat (stemp, "  You can help to improve the quality of APRS signals.", sizeof(stemp));
	    strlcat (stemp, "\nTell the sender (", sizeof(stemp));
	    strlcat (stemp, A->g_src, sizeof(stemp));
	    strlcat (stemp, ") to use the proper product code from", sizeof(stemp));
	    strlcat (stemp, " http://www.aprs.org/aprs11/tocalls.txt", sizeof(stemp));
	  }
	  else {
	    strlcat (stemp, ", ", sizeof(stemp));
	    strlcat (stemp, A->g_mfr, sizeof(stemp));
	  }
	}

	//dw_printf ("DEBUG decode_aprs_print stemp4=%s\n", stemp);

	if (strlen(A->g_mic_e_status) > 0) {
	  strlcat (stemp, ", ", sizeof(stemp));
	  strlcat (stemp, A->g_mic_e_status, sizeof(stemp));
	}

	//dw_printf ("DEBUG decode_aprs_print stemp5=%s\n", stemp);

	if (A->g_power > 0) {
	  char phg[100];

	  /* Protocol spec doesn't mention whether this is dBd or dBi.  */
	  /* Clarified later. */
	  /* http://eng.usna.navy.mil/~bruninga/aprs/aprs11.html */
	  /* "The Antenna Gain in the PHG format on page 28 is in dBi." */

	  snprintf (phg, sizeof(phg), ", %d W height=%d %ddBi %s", A->g_power, A->g_height, A->g_gain, A->g_directivity);
	  strlcat (stemp, phg, sizeof(stemp));
	}

	if (A->g_range > 0) {
	  char rng[100];

	  snprintf (rng, sizeof(rng), ", range=%.1f", A->g_range);
	  strlcat (stemp, rng, sizeof(stemp));
	}

	if (strncmp(stemp, "ERROR", 5) == 0) {
	  text_color_set(DW_COLOR_ERROR);
	}
	else {
	  text_color_set(DW_COLOR_DECODED);
	}
	dw_printf("%s\n", stemp);

/*
 * Second line has:
 * - Latitude
 * - Longitude
 * - speed
 * - direction
 * - altitude
 * - frequency
 */


/*
 * Convert Maidenhead locator to latitude and longitude.
 * 
 * Any example was checked for each hemihemisphere using
 * http://www.amsat.org/cgi-bin/gridconv
 */

	if (strlen(A->g_maidenhead) > 0) {

	  if (A->g_lat == G_UNKNOWN && A->g_lon == G_UNKNOWN) {

	    ll_from_grid_square (A->g_maidenhead, &(A->g_lat), &(A->g_lon));
	  }

	  dw_printf("Grid square = %s, ", A->g_maidenhead);
	}

	strlcpy (stemp, "", sizeof(stemp));

	if (A->g_lat != G_UNKNOWN || A->g_lon != G_UNKNOWN) {

// Have location but it is possible one part is invalid.

	  if (A->g_lat != G_UNKNOWN) {
  
	    if (A->g_lat >= 0) {
	      absll = A->g_lat;
	      news = 'N';
	    }
	    else {
	      absll = - A->g_lat;
	      news = 'S';
	    }
	    deg = (int) absll;
	    min = (absll - deg) * 60.0;
	    snprintf (s_lat, sizeof(s_lat), "%c %02d%s%07.4f", news, deg, CH_DEGREE, min);
	  }
	  else {
	    strlcpy (s_lat, "Invalid Latitude", sizeof(s_lat));
	  }

	  if (A->g_lon != G_UNKNOWN) {

	    if (A->g_lon >= 0) {
	      absll = A->g_lon;
	      news = 'E';
	    }
	    else {
	      absll = - A->g_lon;
	      news = 'W';
	    }
	    deg = (int) absll;
	    min = (absll - deg) * 60.0;
	    snprintf (s_lon, sizeof(s_lon), "%c %03d%s%07.4f", news, deg, CH_DEGREE, min);
	  }
	  else {
	    strlcpy (s_lon, "Invalid Longitude", sizeof(s_lon));
	  }	

	  snprintf (stemp, sizeof(stemp), "%s, %s", s_lat, s_lon);
	}

	if (strlen(A->g_aprstt_loc) > 0) {
	  if (strlen(stemp) > 0) strlcat (stemp, ", ", sizeof(stemp));
	  strlcat (stemp, A->g_aprstt_loc, sizeof(stemp));
	};

	if (A->g_speed_mph != G_UNKNOWN) {
	  char spd[32];

	  if (strlen(stemp) > 0) strlcat (stemp, ", ", sizeof(stemp));
	  snprintf (spd, sizeof(spd), "%.0f km/h (%.0f MPH)", DW_MILES_TO_KM(A->g_speed_mph), A->g_speed_mph);
	  strlcat (stemp, spd, sizeof(stemp));
	};

	if (A->g_course != G_UNKNOWN) {
	  char cse[20];

	  if (strlen(stemp) > 0) strlcat (stemp, ", ", sizeof(stemp));
	  snprintf (cse, sizeof(cse), "course %.0f", A->g_course);
	  strlcat (stemp, cse, sizeof(stemp));
	};

	if (A->g_altitude_ft != G_UNKNOWN) {
	  char alt[32];

	  if (strlen(stemp) > 0) strlcat (stemp, ", ", sizeof(stemp));
	  snprintf (alt, sizeof(alt), "alt %.0f m (%.0f ft)", DW_FEET_TO_METERS(A->g_altitude_ft), A->g_altitude_ft);
	  strlcat (stemp, alt, sizeof(stemp));
	};

	if (A->g_freq != G_UNKNOWN) {
	  char ftemp[30];

	  snprintf (ftemp, sizeof(ftemp), ", %.3f MHz", A->g_freq);
	  strlcat (stemp, ftemp, sizeof(stemp));
	}

	if (A->g_offset != G_UNKNOWN) {
	  char ftemp[30];

	  if (A->g_offset % 1000 == 0) {
	    snprintf (ftemp, sizeof(ftemp), ", %+dM", A->g_offset/1000);
	  }
	  else {
	    snprintf (ftemp, sizeof(ftemp), ", %+dk", A->g_offset);
	  }
	  strlcat (stemp, ftemp, sizeof(stemp));
	}

	if (A->g_tone != G_UNKNOWN) {
	  if (A->g_tone == 0) {
	    strlcat (stemp, ", no PL", sizeof(stemp));
	  }
	  else {
	    char ftemp[30];

	    snprintf (ftemp, sizeof(ftemp), ", PL %.1f", A->g_tone);
	    strlcat (stemp, ftemp, sizeof(stemp));
	  }
	}

	if (A->g_dcs != G_UNKNOWN) {

	  char ftemp[30];

	  snprintf (ftemp, sizeof(ftemp), ", DCS %03o", A->g_dcs);
	  strlcat (stemp, ftemp, sizeof(stemp));
	}

	if (strlen (stemp) > 0) {
	  text_color_set(DW_COLOR_DECODED);
	  dw_printf("%s\n", stemp);
	}


/*
 * Finally, any weather and/or comment.
 *
 * Non-printable characters are changed to safe hexadecimal representations.
 * For example, carriage return is displayed as <0x0d>.
 *
 * Drop annoying trailing CR LF.  Anyone who cares can see it in the raw datA->
 */

	n = strlen(A->g_weather);
	if (n >= 1 && A->g_weather[n-1] == '\n') {
	  A->g_weather[n-1] = '\0';
	  n--;
	}
	if (n >= 1 && A->g_weather[n-1] == '\r') {
	  A->g_weather[n-1] = '\0';
	  n--;
	}
	if (n > 0) {  
	  ax25_safe_print (A->g_weather, -1, 0);
	  dw_printf("\n");
	}


	if (strlen(A->g_telemetry) > 0) {
	  ax25_safe_print (A->g_telemetry, -1, 0);
	  dw_printf("\n");
	}


	n = strlen(A->g_comment);
	if (n >= 1 && A->g_comment[n-1] == '\n') {
	  A->g_comment[n-1] = '\0';
	  n--;
	}
	if (n >= 1 && A->g_comment[n-1] == '\r') {
	  A->g_comment[n-1] = '\0';
	  n--;
	}
	if (n > 0) {
	  int j;

	  ax25_safe_print (A->g_comment, -1, 0);
	  dw_printf("\n");

/*
 * Point out incorrect attempts a degree symbol.
 * 0xb0 is degree in ISO Latin1.
 * To be part of a valid UTF-8 sequence, it would need to be preceded by 11xxxxxx or 10xxxxxx.
 * 0xf8 is degree in Microsoft code page 437.
 * To be part of a valid UTF-8 sequence, it would need to be followed by 10xxxxxx.
 */

// For values 00-7F, ASCII, Unicode, and ISO Latin-1 are all the same.
// ISO Latin-1 adds 80-FF range with a few common symbols, such as degree, and
// letters, with diacritical marks, for many European languages.
// Unicode range 80-FF is called "Latin-1 Supplement."  Exactly the same as ISO Latin-1.
// For UTF-8, an additional byte is inserted.
//	Unicode		UTF-8
//	-------		-----
//	8x		C2 8x		Insert C2, keep original
//	9x		C2 9x		"
//	Ax		C2 Ax		"
//	Bx		C2 Bx		"
//	Cx		C3 8x		Insert C3, subtract 40 from original
//	Dx		C3 9x		"
//	Ex		C3 Ax		"
//	Fx		C3 Bx		"
//
// Can we use this knowledge to provide guidance on other ISO Latin-1 characters besides degree?
// Should we?
// Reference:   https://www.fileformat.info/info/unicode/utf8test.htm

	  if ( ! A->g_quiet) {

	    for (j=0; j<n; j++) {
	      if ((unsigned char)(A->g_comment[j]) == 0xb0 &&  (j == 0 || ! (A->g_comment[j-1] & 0x80))) {
	        text_color_set(DW_COLOR_ERROR);
	        dw_printf("Character code 0xb0 is probably an attempt at a degree symbol.\n");
	        dw_printf("The correct encoding is 0xc2 0xb0 in UTF-8.\n");
	      }	    	
	    }
	    for (j=0; j<n; j++) {
	      if ((unsigned char)(A->g_comment[j]) == 0xf8 && (j == n-1 || (A->g_comment[j+1] & 0xc0) != 0xc0)) {
	        text_color_set(DW_COLOR_ERROR);
	        dw_printf("Character code 0xf8 is probably an attempt at a degree symbol.\n");
	        dw_printf("The correct encoding is 0xc2 0xb0 in UTF-8.\n");	    	
	      }	
	    }
	  }	
	}
}



/*------------------------------------------------------------------
 *
 * Function:	aprs_ll_pos
 *
 * Purpose:	Decode "Lat/Long Position Report - without Timestamp"
 *
 *		Reports without a timestamp can be regarded as real-time.
 *
 * Inputs:	info 	- Pointer to Information field.
 *		ilen 	- Information field length.
 *
 * Outputs:	A->g_lat, A->g_lon, A->g_symbol_table, A->g_symbol_code, A->g_speed_mph, A->g_course, A->g_altitude_ft.
 *
 * Description:	Type identifier '=' has APRS messaging.
 *		Type identifier '!' does not have APRS messaging.
 *
 *		The location can be in either compressed or human-readable form.
 *
 *		When the symbol code is '_' this is a weather report.
 *
 * Examples:	!4309.95NS07307.13W#PHG3320 W2,NY2 Mt Equinox VT k2lm@arrl.net
 *		!4237.14NS07120.83W#
 * 		=4246.40N/07115.15W# {UIV32}
 *
 *		TODO: (?) Special case, DF report when sym table id = '/' and symbol code = '\'.
 *
 * 		=4903.50N/07201.75W\088/036/270/729
 *
 *------------------------------------------------------------------*/

static void aprs_ll_pos (decode_aprs_t *A, unsigned char *info, int ilen) 
{

	struct aprs_ll_pos_s {
	  char dti;			/* ! or = */
	  position_t pos;
	  char comment[43]; 		/* Start of comment could be data extension(s). */
	} *p;

	struct aprs_compressed_pos_s {
	  char dti;			/* ! or = */
	  compressed_position_t cpos;
	  char comment[40]; 		/* No data extension allowed for compressed location. */
	} *q;


	strlcpy (A->g_data_type_desc, "Position", sizeof(A->g_data_type_desc));

	p = (struct aprs_ll_pos_s *)info;
	q = (struct aprs_compressed_pos_s *)info;
	
	if (isdigit((unsigned char)(p->pos.lat[0]))) 	/* Human-readable location. */
        {
	  decode_position (A, &(p->pos));

	  if (A->g_symbol_code == '_') {
	    /* Symbol code indidates it is a weather report. */
	    /* In this case, we expect 7 byte "data extension" */
	    /* for the wind direction and speed. */

	    strlcpy (A->g_data_type_desc, "Weather Report", sizeof(A->g_data_type_desc));
	    weather_data (A, p->comment, TRUE);
/*
Here is an interesting case.
The protocol spec states that a position report with symbol _ is a special case
and the information part must contain wxnow.txt format weather data.
But, here we see it being generated like a normal position report.

N8VIM>BEACON,AB1OC-10*,WIDE2-1:!4240.85N/07133.99W_PHG72604/ Pepperell, MA. WX. 442.9+ PL100<0x0d>
Didn't find wind direction in form c999.
Didn't find wind speed in form s999.
Didn't find wind gust in form g999.
Didn't find temperature in form t999.
Weather Report, WEATHER Station (blue)
N 42 40.8500, W 071 33.9900
, "PHG72604/ Pepperell, MA. WX. 442.9+ PL100"

It seems, to me, that this is a violation of the protocol spec.
Then, immediately following, we have a positionless weather report in Ultimeter format.

N8VIM>APN391,AB1OC-10*,WIDE2-1:$ULTW006F00CA01421C52275800008A00000102FA000F04A6000B002A<0x0d><0x0a>
Ultimeter, Kantronics KPC-3 rom versions
wind 6.9 mph, direction 284, temperature 32.2, barometer 29.75, humidity 76

aprs.fi merges these two together.  Is that anywhere in the protocol spec or
just a heuristic added after noticing a pair of packets like this?
*/

	  } 
	  else {
	    /* Regular position report. */

	    data_extension_comment (A, p->comment);
	  }
	}
	else					/* Compressed location. */
	{
	  decode_compressed_position (A, &(q->cpos));

	  if (A->g_symbol_code == '_') {
	    /* Symbol code indidates it is a weather report. */
	    /* In this case, the wind direction and speed are in the */
	    /* compressed data so we don't expect a 7 byte "data */
	    /* extension" for them. */

	    strlcpy (A->g_data_type_desc, "Weather Report", sizeof(A->g_data_type_desc));
	    weather_data (A, q->comment, FALSE);
	  } 
	  else {
	    /* Regular position report. */

	    process_comment (A, q->comment, -1);
	  }
	}


}



/*------------------------------------------------------------------
 *
 * Function:	aprs_ll_pos_time
 *
 * Purpose:	Decode "Lat/Long Position Report - with Timestamp"
 *
 *		Reports sent with a timestamp might contain very old information.
 *
 *		Otherwise, same as above.
 *
 * Inputs:	info 	- Pointer to Information field.
 *		ilen 	- Information field length.
 *
 * Outputs:	A->g_lat, A->g_lon, A->g_symbol_table, A->g_symbol_code, A->g_speed_mph, A->g_course, A->g_altitude_ft.
 *
 * Description:	Type identifier '@' has APRS messaging.
 *		Type identifier '/' does not have APRS messaging.
 *
 *		The location can be in either compressed or human-readable form.
 *
 *		When the symbol code is '_' this is a weather report.
 *
 * Examples:	@041025z4232.32N/07058.81W_124/000g000t036r000p000P000b10229h65/wx rpt
 * 		@281621z4237.55N/07120.20W_017/002g006t022r000p000P000h85b10195.Dvs
 *		/092345z4903.50N/07201.75W>Test1234
 *
 * 		I think the symbol code of "_" indicates weather report.
 *
 *		(?) Special case, DF report when sym table id = '/' and symbol code = '\'.
 *
 *		@092345z4903.50N/07201.75W\088/036/270/729
 *		/092345z4903.50N/07201.75W\000/000/270/729
 *
 *------------------------------------------------------------------*/



static void aprs_ll_pos_time (decode_aprs_t *A, unsigned char *info, int ilen) 
{

	struct aprs_ll_pos_time_s {
	  char dti;			/* / or @ */
	  char time_stamp[7];
	  position_t pos;
	  char comment[43]; 		/* First 7 bytes could be data extension. */
	} *p;

	struct aprs_compressed_pos_time_s {
	  char dti;			/* / or @ */
	  char time_stamp[7];
	  compressed_position_t cpos;
	  char comment[40]; 		/* No data extension in this case. */
	} *q;


	strlcpy (A->g_data_type_desc, "Position with time", sizeof(A->g_data_type_desc));

	time_t ts = 0;


	p = (struct aprs_ll_pos_time_s *)info;
	q = (struct aprs_compressed_pos_time_s *)info;
	

	if (isdigit((unsigned char)(p->pos.lat[0]))) 		/* Human-readable location. */
        {
	  ts = get_timestamp (A, p->time_stamp);
	  decode_position (A, &(p->pos));

	  if (A->g_symbol_code == '_') {
	    /* Symbol code indidates it is a weather report. */
	    /* In this case, we expect 7 byte "data extension" */
	    /* for the wind direction and speed. */

	    strlcpy (A->g_data_type_desc, "Weather Report", sizeof(A->g_data_type_desc));
	    weather_data (A, p->comment, TRUE);
	  } 
	  else {
	    /* Regular position report. */

	    data_extension_comment (A, p->comment);
	  }
	}
	else					/* Compressed location. */
	{
	  ts = get_timestamp (A, p->time_stamp);

	  decode_compressed_position (A, &(q->cpos));

	  if (A->g_symbol_code == '_') {
	    /* Symbol code indidates it is a weather report. */
	    /* In this case, the wind direction and speed are in the */
	    /* compressed data so we don't expect a 7 byte "data */
	    /* extension" for them. */

	    strlcpy (A->g_data_type_desc, "Weather Report", sizeof(A->g_data_type_desc));
	    weather_data (A, q->comment, FALSE);
	  } 
	  else {
	    /* Regular position report. */

	    process_comment (A, q->comment, -1);
	  }
	}

	(void)(ts);	// suppress 'set but not used' warning.
}


/*------------------------------------------------------------------
 *
 * Function:	aprs_raw_nmea
 *
 * Purpose:	Decode "Raw NMEA Position Report"
 *
 * Inputs:	info 	- Pointer to Information field.
 *		ilen 	- Information field length.
 *
 * Outputs:	A-> ...
 *
 * Description:	APRS recognizes raw ASCII data strings conforming to the NMEA 0183
 *		Version 2.0 specification, originating from navigation equipment such 
 *		as GPS and LORAN receivers. It is recommended that APRS stations 
 *		interpret at least the following NMEA Received Sentence types:
 *
 *		GGA Global Positioning System Fix Data
 *		GLL Geographic Position, Latitude/Longitude Data
 *		RMC Recommended Minimum Specific GPS/Transit Data
 *		VTG Velocity and Track Data
 *		WPL Way Point Location
 *
 *		We presently recognize only RMC and GGA.
 *
 * Examples:	$GPGGA,102705,5157.9762,N,00029.3256,W,1,04,2.0,75.7,M,47.6,M,,*62
 *		$GPGLL,2554.459,N,08020.187,W,154027.281,A
 *		$GPRMC,063909,A,3349.4302,N,11700.3721,W,43.022,89.3,291099,13.6,E*52
 *		$GPVTG,318.7,T,,M,35.1,N,65.0,K*69
 *
 *------------------------------------------------------------------*/


static void aprs_raw_nmea (decode_aprs_t *A, unsigned char *info, int ilen) 
{
	if (strncmp((char*)info, "$GPRMC,", 7) == 0 ||
	    strncmp((char*)info, "$GNRMC,", 7) == 0)
	{
	  float speed_knots = G_UNKNOWN;

	  (void) dwgpsnmea_gprmc ((char*)info, A->g_quiet, &(A->g_lat), &(A->g_lon), &speed_knots, &(A->g_course));
	  A->g_speed_mph = DW_KNOTS_TO_MPH(speed_knots);
	  strlcpy (A->g_data_type_desc, "Raw GPS data", sizeof(A->g_data_type_desc));
	}
	else if (strncmp((char*)info, "$GPGGA,", 7) == 0 ||
	         strncmp((char*)info, "$GNGGA,", 7) == 0)
	{
	  float alt_meters = G_UNKNOWN;
	  int num_sat = 0;

	  (void) dwgpsnmea_gpgga ((char*)info, A->g_quiet, &(A->g_lat), &(A->g_lon), &alt_meters, &num_sat);
	  A->g_altitude_ft = DW_METERS_TO_FEET(alt_meters);
	  strlcpy (A->g_data_type_desc, "Raw GPS data", sizeof(A->g_data_type_desc));
	}

	// TODO (low): add a few other sentence types.

} /* end aprs_raw_nmea */



/*------------------------------------------------------------------
 *
 * Function:	aprs_mic_e
 *
 * Purpose:	Decode MIC-E (also Kenwood D7 & D700) packet.
 *
 * Inputs:	info 	- Pointer to Information field.
 *		ilen 	- Information field length.
 *
 * Outputs:	
 *
 * Description:	
 *
 *		Destination Address Field - 
 *
 *		The 7-byte Destination Address field contains
 *		the following encoded information:
 *
 *		* The 6 latitude digits.
 *		* A 3-bit Mic-E message identifier, specifying one of 7 Standard Mic-E
 *		   Message Codes or one of 7 Custom Message Codes or an Emergency
 *		   Message Code.
 *		* The North/South and West/East Indicators.
 *		* The Longitude Offset Indicator.
 *		* The generic APRS digipeater path code.
 *
 *		"Although the destination address appears to be quite unconventional, it is
 *		still a valid AX.25 address, consisting only of printable 7-bit ASCII values."
 *
 * References:	Mic-E TYPE CODES -- http://www.aprs.org/aprs12/mic-e-types.txt
 *
 *			This is up to date with the 24 Aug 16 version mentioning the TH-D74.
 *
 *		Mic-E TEST EXAMPLES -- http://www.aprs.org/aprs12/mic-e-examples.txt 
 *		
 * Examples:	`b9Z!4y>/>"4N}Paul's_TH-D7
 *
 * TODO:	Destination SSID can contain generic digipeater path.
 *
 * Bugs:	Doesn't handle ambiguous position.  "space" treated as zero.
 *		Invalid data results in a message but latitude is not set to unknown.
 *
 *------------------------------------------------------------------*/

/* a few test cases

# example from http://www.aprs.org/aprs12/mic-e-examples.txt produces 4 errors.
# TODO:  Analyze all the bits someday and possibly report problem with document.

N0CALL>ABCDEF:'abc123R/text

# Let's use an actual valid location and concentrate on the manufacturers
# as listed in http://www.aprs.org/aprs12/mic-e-types.txt

N1ZZN-9>T2SP0W:`c_Vm6hk/`"49}Jeff Mobile_%

N1ZZN-9>T2SP0W:`c_Vm6hk/ "49}Originl Mic-E (leading space)

N1ZZN-9>T2SP0W:`c_Vm6hk/>"49}TH-D7A walkie Talkie
N1ZZN-9>T2SP0W:`c_Vm6hk/>"49}TH-D72 walkie Talkie=
W6GPS>S4PT3R:`p(1oR0K\>TH-D74A^
N1ZZN-9>T2SP0W:`c_Vm6hk/]"49}TM-D700 MObile Radio
N1ZZN-9>T2SP0W:`c_Vm6hk/]"49}TM-D710 Mobile Radio=

# Note: next line has trailing space character after _

N1ZZN-9>T2SP0W:`c_Vm6hk/`"49}Yaesu VX-8_ 
N1ZZN-9>T2SP0W:`c_Vm6hk/`"49}Yaesu FTM-350_"
N1ZZN-9>T2SP0W:`c_Vm6hk/`"49}Yaesu VX-8G_#
N1ZZN-9>T2SP0W:`c_Vm6hk/`"49}Yaesu FT1D_$
N1ZZN-9>T2SP0W:`c_Vm6hk/`"49}Yaesu FTM-400DR_%

N1ZZN-9>T2SP0W:'c_Vm6hk/`"49}Byonics TinyTrack3|3
N1ZZN-9>T2SP0W:'c_Vm6hk/`"49}Byonics TinyTrack4|4

# The next group starts with metacharacter "T" which can be any of space > ] ` '
# But space is for original Mic-E, # > and ] are for Kenwood, 
# so ` ' would probably be less ambiguous choices but any appear to be valid.

N1ZZN-9>T2SP0W:'c_Vm6hk/`"49}Hamhud\9
N1ZZN-9>T2SP0W:'c_Vm6hk/`"49}Argent/9
N1ZZN-9>T2SP0W:'c_Vm6hk/`"49}HinzTec anyfrog^9
N1ZZN-9>T2SP0W:'c_Vm6hk/`"49}APOZxx www.KissOZ.dk Tracker. OZ1EKD and OZ7HVO*9
N1ZZN-9>T2SP0W:'c_Vm6hk/`"49}OTHER~9


# TODO:  Why is manufacturer unknown?  Should we explicitly say unknown?

[0] VE2VL-9>TU3V0P,VE2PCQ-3,WIDE1,W1UWS-1,UNCAN,WIDE2*:`eB?l")v/"3y}
MIC-E, VAN, En Route

[0] VE2VL-9>TU3U5Q,VE2PCQ-3,WIDE1,W1UWS-1,N1NCI-3,WIDE2*:`eBgl"$v/"42}73 de Julien, Tinytrak 3
MIC-E, VAN, En Route

[0] W1ERB-9>T1SW8P,KB1AEV-15,N1NCI-3,WIDE2*:`dI8l!#j/"3m}
MIC-E, JEEP, In Service

[0] W1ERB-9>T1SW8Q,KB1AEV-15,N1NCI-3,WIDE2*:`dI6l{^j/"4+}IntheJeep..try146.79(PVRA)
"146.79" in comment looks like a frequency in non-standard format.
For most systems to recognize it, use exactly this form "146.790MHz" at beginning of comment.
MIC-E, JEEP, In Service

*/

static int mic_e_digit (decode_aprs_t *A, char c, int mask, int *std_msg, int *cust_msg)
{

 	if (c >= '0' && c <= '9') {
	  return (c - '0');
	}

	if (c >= 'A' && c <= 'J') {
	  *cust_msg |= mask;
	  return (c - 'A');
	}

	if (c >= 'P' && c <= 'Y') {
	  *std_msg |= mask;
	  return (c - 'P');
	}

	/* K, L, Z should be converted to space. */
	/* others are invalid. */
	/* But caller expects only values 0 - 9. */

	if (c == 'K') {
	  *cust_msg |= mask;
	  return (0);
	}

	if (c == 'L') {
	  return (0);
	}

	if (c == 'Z') {
	  *std_msg |= mask;
	  return (0);
	}

	if ( ! A->g_quiet) {
	  text_color_set(DW_COLOR_ERROR);
	  dw_printf("Invalid character \"%c\" in MIC-E destination/latitude.\n", c);
	}

	return (0);
}


static void aprs_mic_e (decode_aprs_t *A, packet_t pp, unsigned char *info, int ilen) 
{
	struct aprs_mic_e_s {
	  char dti;			/* ' or ` */
	  unsigned char lon[3];		/* "d+28", "m+28", "h+28" */
	  unsigned char speed_course[3];		
	  char symbol_code;
	  char sym_table_id;
	} *p;

	char dest[12];
	int ch;
	int n;
	int offset;
	int std_msg = 0;
	int cust_msg = 0;
	const char *std_text[8] = {"Emergency", "Priority", "Special", "Committed", "Returning", "In Service", "En Route", "Off Duty" };
	const char *cust_text[8] = {"Emergency", "Custom-6", "Custom-5", "Custom-4", "Custom-3", "Custom-2", "Custom-1", "Custom-0" }; 
	unsigned char *pfirst, *plast;

	strlcpy (A->g_data_type_desc, "MIC-E", sizeof(A->g_data_type_desc));

	p = (struct aprs_mic_e_s *)info;

/* Destination is really latitude of form ddmmhh. */
/* Message codes are buried in the first 3 digits. */

	ax25_get_addr_with_ssid (pp, AX25_DESTINATION, dest);

	A->g_lat = mic_e_digit(A, dest[0], 4, &std_msg, &cust_msg) * 10 + 
		mic_e_digit(A, dest[1], 2, &std_msg, &cust_msg) +
		(mic_e_digit(A, dest[2], 1, &std_msg, &cust_msg) * 1000 + 
		 mic_e_digit(A, dest[3], 0, &std_msg, &cust_msg) * 100 + 
		 mic_e_digit(A, dest[4], 0, &std_msg, &cust_msg) * 10 + 
		 mic_e_digit(A, dest[5], 0, &std_msg, &cust_msg)) / 6000.0;


/* 4th character of destination indicates north / south. */

	if ((dest[3] >= '0' && dest[3] <= '9') || dest[3] == 'L') {
	  /* South */
	  A->g_lat = ( - A->g_lat);
	}
	else if (dest[3] >= 'P' && dest[3] <= 'Z') 
	{
	  /* North */
	}
	else 
	{
	  if ( ! A->g_quiet) {
	    text_color_set(DW_COLOR_ERROR);
	    dw_printf("Invalid MIC-E N/S encoding in 4th character of destination.\n");	  
	  }
	}


/* Longitude is mostly packed into 3 bytes of message but */
/* has a couple bits of information in the destination. */

	if ((dest[4] >= '0' && dest[4] <= '9') || dest[4] == 'L') 
	{
	  offset = 0;
	}
	else if (dest[4] >= 'P' && dest[4] <= 'Z') 
	{
	  offset = 1;
	}
	else 
	{
	  offset = 0;
	  if ( ! A->g_quiet) {
	    text_color_set(DW_COLOR_ERROR);
	    dw_printf("Invalid MIC-E Longitude Offset in 5th character of destination.\n");
	  }
	}

/* First character of information field is longitude in degrees. */
/* It is possible for the unprintable DEL character to occur here. */

/* 5th character of destination indicates longitude offset of +100. */
/* Not quite that simple :-( */

	ch = p->lon[0];

	if (offset && ch >= 118 && ch <= 127) 
	{
	    A->g_lon = ch - 118;			/* 0 - 9 degrees */
	}
	else if ( ! offset && ch >= 38 && ch <= 127)
	{
	    A->g_lon = (ch - 38) + 10;		/* 10 - 99 degrees */
	}
	else if (offset && ch >= 108 && ch <= 117)
	{
	    A->g_lon = (ch - 108) + 100;		/* 100 - 109 degrees */
	}
	else if (offset && ch >= 38 && ch <= 107)
	{
	    A->g_lon = (ch - 38) + 110;		/* 110 - 179 degrees */
	}
	else 
	{
	   A->g_lon = G_UNKNOWN;
	   if ( ! A->g_quiet) {
	     text_color_set(DW_COLOR_ERROR);
	     dw_printf("Invalid character 0x%02x for MIC-E Longitude Degrees.\n", ch);
	   }
	}

/* Second character of information field is A->g_longitude minutes. */
/* These are all printable characters. */

/* 
 * More than once I've see the TH-D72A put <0x1a> here and flip between north and south.
 *
 * WB2OSZ>TRSW1R,WIDE1-1,WIDE2-2:`c0ol!O[/>=<0x0d>
 * N 42 37.1200, W 071 20.8300, 0 MPH, course 151
 *
 * WB2OSZ>TRS7QR,WIDE1-1,WIDE2-2:`v<0x1a>n<0x1c>"P[/>=<0x0d>
 * Invalid character 0x1a for MIC-E Longitude Minutes.
 * S 42 37.1200, Invalid Longitude, 0 MPH, course 252
 *
 * This was direct over the air with no opportunity for a digipeater
 * or anything else to corrupt the message.
 */

	if (A->g_lon != G_UNKNOWN) 
	{
	  ch = p->lon[1];

	  if (ch >= 88 && ch <= 97)
	  {
	    A->g_lon += (ch - 88) / 60.0;	/* 0 - 9 minutes*/
	  }
	  else if (ch >= 38 && ch <= 87)
	  {
    	    A->g_lon += ((ch - 38) + 10) / 60.0;	/* 10 - 59 minutes */
	  }
	  else {
	    A->g_lon = G_UNKNOWN;
	    if ( ! A->g_quiet) {
	      text_color_set(DW_COLOR_ERROR);
	      dw_printf("Invalid character 0x%02x for MIC-E Longitude Minutes.\n", ch);
	    }
	  }

/* Third character of information field is longitude hundredths of minutes. */
/* There are 100 possible values, from 0 to 99. */
/* Note that the range includes 4 unprintable control characters and DEL. */

	  if (A->g_lon != G_UNKNOWN) 
	  {
	    ch = p->lon[2];

	    if (ch >= 28 && ch <= 127) 
	    {
	      A->g_lon += ((ch - 28) + 0) / 6000.0;	/* 0 - 99 hundredths of minutes*/
	    }
	    else {
	      A->g_lon = G_UNKNOWN;
	      if ( ! A->g_quiet) { 
	        text_color_set(DW_COLOR_ERROR);
	        dw_printf("Invalid character 0x%02x for MIC-E Longitude hundredths of Minutes.\n", ch);
	      }
	    }
	  }
	}

/* 6th character of destination indicates east / west. */

/*
 * Example of apparently invalid encoding.  6th character missing.
 *
 * [0] KB1HOZ-9>TTRW5,KQ1L-2,WIDE1,KQ1L-8,UNCAN,WIDE2*:`aFo"]|k/]"4m}<0x0d>
 * Invalid character "Invalid MIC-E E/W encoding in 6th character of destination.
 * MIC-E, truck, Kenwood TM-D700, Off Duty
 * N 44 27.5000, E 069 42.8300, 76 MPH, course 196, alt 282 ft
 */

	if ((dest[5] >= '0' && dest[5] <= '9') || dest[5] == 'L') {
	  /* East */
	}
	else if (dest[5] >= 'P' && dest[5] <= 'Z') 
	{
	  /* West */
	  if (A->g_lon != G_UNKNOWN) {
	    A->g_lon = ( - A->g_lon);
	  }
	}
	else 
	{
	  if ( ! A->g_quiet) {
	    text_color_set(DW_COLOR_ERROR);
	    dw_printf("Invalid MIC-E E/W encoding in 6th character of destination.\n");	  
	  }
	}

/* Symbol table and codes like everyone else. */

	A->g_symbol_table = p->sym_table_id;
	A->g_symbol_code = p->symbol_code;

	if (A->g_symbol_table != '/' && A->g_symbol_table != '\\' 
		&& ! isupper(A->g_symbol_table) && ! isdigit(A->g_symbol_table))
	{
	  if ( ! A->g_quiet) {
	    text_color_set(DW_COLOR_ERROR);
	    dw_printf("Invalid symbol table code not one of / \\ A-Z 0-9\n");	
	  }
	  A->g_symbol_table = '/';
	}

/* Message type from two 3-bit codes. */

	if (std_msg == 0 && cust_msg == 0) {
	  strlcpy (A->g_mic_e_status, "Emergency", sizeof(A->g_mic_e_status));
	}
	else if (std_msg == 0 && cust_msg != 0) {
	  strlcpy (A->g_mic_e_status, cust_text[cust_msg], sizeof(A->g_mic_e_status));
	}
	else if (std_msg != 0 && cust_msg == 0) {
	  strlcpy (A->g_mic_e_status, std_text[std_msg], sizeof(A->g_mic_e_status));
	}
	else {
	  strlcpy (A->g_mic_e_status, "Unknown MIC-E Message Type", sizeof(A->g_mic_e_status));
	}

/* Speed and course from next 3 bytes. */

	n = ((p->speed_course[0] - 28) * 10) + ((p->speed_course[1] - 28) / 10);
	if (n >= 800) n -= 800;

	A->g_speed_mph = DW_KNOTS_TO_MPH(n);

	n = ((p->speed_course[1] - 28) % 10) * 100 + (p->speed_course[2] - 28);
	if (n >= 400) n -= 400;

	/* Result is 0 for unknown and 1 - 360 where 360 is north. */
	/* Convert to 0 - 360 and reserved value for unknown. */

	if (n == 0) 
	  A->g_course = G_UNKNOWN;
	else if (n == 360)
	  A->g_course = 0;
	else
	  A->g_course = n;


/* Now try to pick out manufacturer and other optional items. */
/* The telemetry field, in the original spec, is no longer used. */
  
	strlcpy (A->g_mfr, "Unknown manufacturer", sizeof(A->g_mfr));

	pfirst = info + sizeof(struct aprs_mic_e_s);
	plast = info + ilen - 1;

/* Carriage return character at the end is not mentioned in spec. */
/* Remove if found because it messes up extraction of manufacturer. */
/* Don't drop trailing space because that is used for Yaesu VX-8. */
/* As I recall, the IGate function trims trailing spaces.  */
/* That would be bad for this particular model. Maybe I'm mistaken? */


	if (*plast == '\r') plast--;

#define isT(c) ((c) == ' ' || (c) == '>' || (c) == ']' || (c) == '`' || (c) == '\'')

// Last Updated Dec. 2021

// This does not change very often but I'm wondering if we could parse
// http://www.aprs.org/aprs12/mic-e-types.txt similar to how we use tocalls.txt.

	if (isT(*pfirst)) {

// "legacy" formats.
	
	  if      (*pfirst == ' '                                       )  { strlcpy (A->g_mfr, "Original MIC-E", sizeof(A->g_mfr)); pfirst++; }

	  else if (*pfirst == '>'                       && *plast == '=')  { strlcpy (A->g_mfr, "Kenwood TH-D72", sizeof(A->g_mfr)); pfirst++; plast--; }
	  else if (*pfirst == '>'                       && *plast == '^')  { strlcpy (A->g_mfr, "Kenwood TH-D74", sizeof(A->g_mfr)); pfirst++; plast--; }
	  else if (*pfirst == '>'                                       )  { strlcpy (A->g_mfr, "Kenwood TH-D7A", sizeof(A->g_mfr)); pfirst++; }

	  else if (*pfirst == ']'                       && *plast == '=')  { strlcpy (A->g_mfr, "Kenwood TM-D710", sizeof(A->g_mfr)); pfirst++; plast--; }
	  else if (*pfirst == ']'                                       )  { strlcpy (A->g_mfr, "Kenwood TM-D700", sizeof(A->g_mfr)); pfirst++; }

// ` should be used for message capable devices.

	  else if (*pfirst == '`'  && *(plast-1) == '_' && *plast == ' ')  { strlcpy (A->g_mfr, "Yaesu VX-8", sizeof(A->g_mfr)); pfirst++; plast-=2; }
	  else if (*pfirst == '`'  && *(plast-1) == '_' && *plast == '"')  { strlcpy (A->g_mfr, "Yaesu FTM-350", sizeof(A->g_mfr)); pfirst++; plast-=2; }
	  else if (*pfirst == '`'  && *(plast-1) == '_' && *plast == '#')  { strlcpy (A->g_mfr, "Yaesu VX-8G", sizeof(A->g_mfr)); pfirst++; plast-=2; }
	  else if (*pfirst == '`'  && *(plast-1) == '_' && *plast == '$')  { strlcpy (A->g_mfr, "Yaesu FT1D", sizeof(A->g_mfr)); pfirst++; plast-=2; }
	  else if (*pfirst == '`'  && *(plast-1) == '_' && *plast == '%')  { strlcpy (A->g_mfr, "Yaesu FTM-400DR", sizeof(A->g_mfr)); pfirst++; plast-=2; }
	  else if (*pfirst == '`'  && *(plast-1) == '_' && *plast == ')')  { strlcpy (A->g_mfr, "Yaesu FTM-100D", sizeof(A->g_mfr)); pfirst++; plast-=2; }
	  else if (*pfirst == '`'  && *(plast-1) == '_' && *plast == '(')  { strlcpy (A->g_mfr, "Yaesu FT2D", sizeof(A->g_mfr)); pfirst++; plast-=2; }
	  else if (*pfirst == '`'  && *(plast-1) == '_' && *plast == '0')  { strlcpy (A->g_mfr, "Yaesu FT3D", sizeof(A->g_mfr)); pfirst++; plast-=2; }
	  else if (*pfirst == '`'  && *(plast-1) == '_' && *plast == '3')  { strlcpy (A->g_mfr, "Yaesu FT5D", sizeof(A->g_mfr)); pfirst++; plast-=2; }
	  else if (*pfirst == '`'  && *(plast-1) == '_' && *plast == '1')  { strlcpy (A->g_mfr, "Yaesu FTM-300D", sizeof(A->g_mfr)); pfirst++; plast-=2; }

	  else if (*pfirst == '`'  && *(plast-1) == ' ' && *plast == 'X')  { strlcpy (A->g_mfr, "AP510", sizeof(A->g_mfr)); pfirst++; plast-=2; }

	  else if (*pfirst == '`'  && *(plast-1) == '(' && *plast == '5')  { strlcpy (A->g_mfr, "Anytone D578UV", sizeof(A->g_mfr)); pfirst++; plast-=2; }
	  else if (*pfirst == '`'                                       )  { strlcpy (A->g_mfr, "Generic Mic-Emsg", sizeof(A->g_mfr)); pfirst++; }

// ' should be used for trackers (not message capable).

	  else if (*pfirst == '\'' && *(plast-1) == '(' && *plast == '8')  { strlcpy (A->g_mfr, "Anytone D878UV", sizeof(A->g_mfr)); pfirst++; plast-=2; }

	  else if (*pfirst == '\'' && *(plast-1) == '|' && *plast == '3')  { strlcpy (A->g_mfr, "Byonics TinyTrack3", sizeof(A->g_mfr)); pfirst++; plast-=2; }
	  else if (*pfirst == '\'' && *(plast-1) == '|' && *plast == '4')  { strlcpy (A->g_mfr, "Byonics TinyTrack4", sizeof(A->g_mfr)); pfirst++; plast-=2; }

	  else if (*pfirst == '\'' && *(plast-1) == ':' && *plast == '4')  { strlcpy (A->g_mfr, "SCS GmbH & Co. P4dragon DR-7400 modems", sizeof(A->g_mfr)); pfirst++; plast-=2; }
	  else if (*pfirst == '\'' && *(plast-1) == ':' && *plast == '8')  { strlcpy (A->g_mfr, "SCS GmbH & Co. P4dragon DR-7800 modems", sizeof(A->g_mfr)); pfirst++; plast-=2; }

	  else if (*pfirst == '\''                                      )  { strlcpy (A->g_mfr, "Generic McTrackr", sizeof(A->g_mfr)); pfirst++; }

	  else if (                   *(plast-1) == '\\'                )  { strlcpy (A->g_mfr, "Hamhud ?", sizeof(A->g_mfr)); pfirst++; plast-=2; }
	  else if (                   *(plast-1) == '/'                 )  { strlcpy (A->g_mfr, "Argent ?", sizeof(A->g_mfr)); pfirst++; plast-=2; }
	  else if (                   *(plast-1) == '^'                 )  { strlcpy (A->g_mfr, "HinzTec anyfrog", sizeof(A->g_mfr)); pfirst++; plast-=2; }
	  else if (                   *(plast-1) == '*'                 )  { strlcpy (A->g_mfr, "APOZxx www.KissOZ.dk Tracker. OZ1EKD and OZ7HVO", sizeof(A->g_mfr)); pfirst++; plast-=2; }
	  else if (                   *(plast-1) == '~'                 )  { strlcpy (A->g_mfr, "Unknown OTHER", sizeof(A->g_mfr)); pfirst++; plast-=2; }
	}

/*
 * An optional altitude is next.
 * It is three base-91 digits followed by "}".
 * The TM-D710A might have encoding bug.  This was observed:
 *
 * KJ4ETP-9>SUUP9Q,KE4OTZ-3,WIDE1*,WIDE2-1,qAR,KI4HDU-2:`oV$n6:>/]"7&}162.475MHz <Knox,TN> clintserman@gmail=
 * N 35 50.9100, W 083 58.0800, 25 MPH, course 230, alt 945 ft, 162.475MHz
 *
 * KJ4ETP-9>SUUP6Y,GRNTOP-3*,WIDE2-1,qAR,KI4HDU-2:`oU~nT >/]<0x9a>xt}162.475MHz <Knox,TN> clintserman@gmail=
 * Invalid character in MIC-E altitude.  Must be in range of '!' to '{'.
 * N 35 50.6900, W 083 57.9800, 29 MPH, course 204, alt 3280843 ft, 162.475MHz
 *
 * KJ4ETP-9>SUUP6Y,N4NEQ-3,K4EGA-1,WIDE2*,qAS,N5CWH-1:`oU~nT >/]?xt}162.475MHz <Knox,TN> clintserman@gmail=
 * N 35 50.6900, W 083 57.9800, 29 MPH, course 204, alt 808497 ft, 162.475MHz
 *
 * KJ4ETP-9>SUUP2W,KE4OTZ-3,WIDE1*,WIDE2-1,qAR,KI4HDU-2:`oV2o"J>/]"7)}162.475MHz <Knox,TN> clintserman@gmail=
 * N 35 50.2700, W 083 58.2200, 35 MPH, course 246, alt 955 ft, 162.475MHz
 * 
 * Note the <0x9a> which is outside of the 7-bit ASCII range.  Clearly very wrong.
 */

	if (plast > pfirst && pfirst[3] == '}') {

	  A->g_altitude_ft = DW_METERS_TO_FEET((pfirst[0]-33)*91*91 + (pfirst[1]-33)*91 + (pfirst[2]-33) - 10000);

	  if ( ! isdigit91(pfirst[0]) || ! isdigit91(pfirst[1]) || ! isdigit91(pfirst[2])) 
	  {
	    if ( ! A->g_quiet) {
	      text_color_set(DW_COLOR_ERROR);
	      dw_printf("Invalid character in MIC-E altitude.  Must be in range of '!' to '{'.\n");
	      dw_printf("Bogus altitude of %.0f changed to unknown.\n", A->g_altitude_ft);
	    }
	    A->g_altitude_ft = G_UNKNOWN;
	  }
	  
	  pfirst += 4;
	}

	process_comment (A, (char*)pfirst, (int)(plast - pfirst) + 1);

}


/*------------------------------------------------------------------
 *
 * Function:	aprs_message
 *
 * Purpose:	Decode "Message Format."
 *		The word message is used loosely all over the place, but it has a very specific meaning here.
 *
 * Inputs:	info 	- Pointer to Information field.  Be careful not to modify it here!
 *		ilen 	- Information field length.
 *		quiet	- suppress error messages.
 *
 * Outputs:	A->g_data_type_desc		Text description for screen display.
 *
 *		A->g_addressee		To whom is it addressed.
 *					Could be a specific station, alias, bulletin, etc.
 *					For telemetry metadata is is about this station,
 *					not being sent to it.
 *
 *		A->g_message_subtype	Subtype so caller might avoid replicating
 *					all the code to distinguish them.
 *
 *		A->g_message_number	Message number if any.  Required for ack/rej.
 *
 * Description:	An APRS message is a text string with a specified addressee.
 *
 *		It's a lot more complicated with different types of addressees
 *		and replies with acknowledgement or rejection.
 *
 *		There is even a special case for telemetry metadata.
 *
 *
 * Cases:	:xxxxxxxxx:PARM.		Telemetry metadata, parameter name
 *		:xxxxxxxxx:UNIT.		Telemetry metadata, unit/label
 *		:xxxxxxxxx:EQNS.		Telemetry metadata, Equation Coefficients
 *		:xxxxxxxxx:BITS.		Telemetry metadata, Bit Sense/Project Name
 *		:xxxxxxxxx:?			Directed Station Query
 *		:xxxxxxxxx:ackNNNN		Message acknowledged (received)
 *		:xxxxxxxxx:rejNNNNN		Message rejected (unable to accept)
 *
 *		:xxxxxxxxx: ...			Message with no message number.
 *						(Text may not contain the { character because
 *						 it indicates beginning of optional message number.)
 *		:xxxxxxxxx: ... {NNNNN		Message with message number, 1 to 5 alphanumeric.
 *		:xxxxxxxxx: ... {mm}		Message with new style message number.
 *		:xxxxxxxxx: ... {mm}aa		Message with new style message number and ack.
 *
 *
 * Reference:	See new message id style:  http://www.aprs.org/aprs11/replyacks.txt
 *
 *------------------------------------------------------------------*/

static void aprs_message (decode_aprs_t *A, unsigned char *info, int ilen, int quiet)
{

	struct aprs_message_s {
	  char dti;			/* : */
	  char addressee[9];
	  char colon;			/* : */
	  char message[256-1-9-1];	/* Officially up to 67 characters for message text. */
					/* Relaxing seemingly arbitrary restriction here; it doesn't need to fit on a punched card. */
					/* Wouldn't surprise me if others did not pay attention to the limit. */
					/* Optional '{' followed by 1-5 alphanumeric characters for message number */

					/* If the first character is '?' it is a Directed Station Query. */
	} *p;

	char addressee[AX25_MAX_ADDR_LEN];
	int i;

	p = (struct aprs_message_s *)info;

	strlcpy (A->g_data_type_desc, "APRS Message", sizeof(A->g_data_type_desc));
	A->g_message_subtype = message_subtype_message;			/* until found otherwise */

	if (ilen < 11) {
	  if (! quiet) {
	    text_color_set(DW_COLOR_ERROR);
	    dw_printf("APRS Message must have a minimum of 11 characters for : 9 character addressee :\n");
	  }
	  A->g_message_subtype = message_subtype_invalid;
	  return;
	}

	if (p->colon != ':') {
	  if (! quiet) {
	    text_color_set(DW_COLOR_ERROR);
	    dw_printf("APRS Message must begin with ':' 9 character addressee ':'\n");
	    dw_printf("Spaces must be added to shorter addressee to make 9 characters.\n");
	  }
	  A->g_message_subtype = message_subtype_invalid;
	  return;
	}

	memset (addressee, 0, sizeof(addressee));
	memcpy (addressee, p->addressee, sizeof(p->addressee));	// copy exactly 9 bytes.

	/* Trim trailing spaces. */
	i = strlen(addressee) - 1;
	while (i >= 0 && addressee[i] == ' ') {
	  addressee[i--] = '\0';
	}

	// Anytone AT-D878UV 2 plus would pad out station name to 6 characters
	// before appending the SSID.  e.g.  "AE7MK -5 "

	// Test cases.  First is valid.  Others should produce errors:
	//
	// cbeacon sendto=r0  delay=0:10  info=":AE7MK-5  :test0"
	// cbeacon sendto=r0  delay=0:15  info=":AE7MK-5:test1"
	// cbeacon sendto=r0  delay=0:20  info=":AE7MK -5 :test2"
	// cbeacon sendto=r0  delay=0:25  info=":AE7   -5 :test3"

	static regex_t bad_addressee_re;	/* Probably bad addressee. */
	static int first_time = 1;

	if (first_time) {
	  char emsg[100];
	  int e = regcomp (&bad_addressee_re, "[A-Z0-9]+ +-[0-9]", REG_EXTENDED);
	  if (e) {
	    regerror (e, &bad_addressee_re, emsg, sizeof(emsg));
	    dw_printf("%s:%d: %s\n", __FILE__, __LINE__, emsg);
	  }
	  first_time = 0;
	}

#define MAXMATCH_AT 2
	regmatch_t match[MAXMATCH_AT];

	if (regexec (&bad_addressee_re, addressee, MAXMATCH_AT, match, 0) == 0) {
	    text_color_set(DW_COLOR_ERROR);
	    dw_printf("Malformed addressee with space between station name and SSID.\n");
	    dw_printf("Please tell message sender this is invalid.\n");
	}

	strlcpy (A->g_addressee, addressee, sizeof(A->g_addressee));


/*
 * Special message formats contain telemetry metadata.
 * It applies to the addressee, not the sender.
 * Makes no sense to me that it would not apply to sender instead.
 * Wouldn't the sender be describing his own data?
 * 
 * I also don't understand the reasoning for putting this in a "message."
 * Telemetry data always starts with "#" after the "T" data type indicator.
 * Why not use other characters after the "T" for metadata?
 */

	if (strncmp(p->message,"PARM.",5) == 0) {
	  snprintf (A->g_data_type_desc, sizeof(A->g_data_type_desc), "Telemetry Parameter Name Message for \"%s\"", addressee);
	  A->g_message_subtype = message_subtype_telem_parm;
	  telemetry_name_message (addressee, p->message+5);
	}
	else if (strncmp(p->message,"UNIT.",5) == 0) {
	  snprintf (A->g_data_type_desc, sizeof(A->g_data_type_desc), "Telemetry Unit/Label Message for \"%s\"", addressee);
	  A->g_message_subtype = message_subtype_telem_unit;
	  telemetry_unit_label_message (addressee, p->message+5);
	}
	else if (strncmp(p->message,"EQNS.",5) == 0) {
	  snprintf (A->g_data_type_desc, sizeof(A->g_data_type_desc), "Telemetry Equation Coefficients Message for \"%s\"", addressee);
	  A->g_message_subtype = message_subtype_telem_eqns;
	  telemetry_coefficents_message (addressee, p->message+5, quiet);
	}
	else if (strncmp(p->message,"BITS.",5) == 0) {
	  snprintf (A->g_data_type_desc, sizeof(A->g_data_type_desc), "Telemetry Bit Sense/Project Name Message for \"%s\"", addressee);
	  A->g_message_subtype = message_subtype_telem_bits;
	  telemetry_bit_sense_message (addressee, p->message+5, quiet);
	}

/*
 * If first character of message is "?" it is a query directed toward a specific station.
 */

	else if (p->message[0] == '?') {

	  strlcpy (A->g_data_type_desc, "Directed Station Query", sizeof(A->g_data_type_desc));
	  A->g_message_subtype = message_subtype_directed_query;

	  aprs_directed_station_query (A, addressee, p->message+1, quiet);
	}

/* ack or rej?  Message number is required for these. */

	else if (strncasecmp(p->message,"ack",3) == 0) {
	  if (strncmp(p->message,"ack",3) != 0) {
	      text_color_set(DW_COLOR_ERROR);
	      dw_printf("ERROR: \"%s\" must be lower case \"ack\"\n", p->message);
	  }
	  strlcpy (A->g_message_number, p->message + 3, sizeof(A->g_message_number));
	  if (strlen(A->g_message_number) == 0) {
	      text_color_set(DW_COLOR_ERROR);
	      dw_printf("ERROR: Message number is missing after \"ack\".\n");
	  }

	  // Xastir puts a carriage return on the end.
	  char *p = strchr(A->g_message_number, '\r');
	  if (p != NULL) {
	      text_color_set(DW_COLOR_ERROR);
	      dw_printf("The APRS protocol specification says nothing about a possible carriage return after the\n");
	      dw_printf("message id.  Adding CR might prevent proper interoperability with with other applications.\n");
	      *p = '\0';
	  }
 
	  if (strlen(A->g_message_number) >= 3 && A->g_message_number[2] == '}') A->g_message_number[2] = '\0';
	  snprintf (A->g_data_type_desc, sizeof(A->g_data_type_desc), "\"%s\" ACKnowledged message number \"%s\" from \"%s\"", A->g_src, A->g_message_number, addressee);
	  A->g_message_subtype = message_subtype_ack;
	}
	else if (strncasecmp(p->message,"rej",3) == 0) {
	  if (strncmp(p->message,"rej",3) != 0) {
	      text_color_set(DW_COLOR_ERROR);
	      dw_printf("ERROR: \"%s\" must be lower case \"rej\"\n", p->message);
	  }
	  strlcpy (A->g_message_number, p->message + 3, sizeof(A->g_message_number));
	  if (strlen(A->g_message_number) == 0) {
	      text_color_set(DW_COLOR_ERROR);
	      dw_printf("ERROR: Message number is missing after \"rej\".\n");
	  }

	  // Xastir puts a carriage return on the end.
	  char *p = strchr(A->g_message_number, '\r');
	  if (p != NULL) {
	      text_color_set(DW_COLOR_ERROR);
	      dw_printf("The APRS protocol specification says nothing about a possible carriage return after the\n");
	      dw_printf("message id.  Adding CR might prevent proper interoperability with with other applications.\n");
	      *p = '\0';
	  }

	  if (strlen(A->g_message_number) >= 3 && A->g_message_number[2] == '}') A->g_message_number[2] = '\0';
	  snprintf (A->g_data_type_desc, sizeof(A->g_data_type_desc), "\"%s\" REJected message number \"%s\" from \"%s\"", A->g_src, A->g_message_number, addressee);
	  A->g_message_subtype = message_subtype_ack;
	}

// Message to a particular station or a bulletin.
// message number is optional here.
// Test cases.  Wrap in third party too.
// A>B::WA1XYX-15:Howdy y'all
// A>B::WA1XYX-15:Howdy y'all{12345
// A>B::WA1XYX-15:Howdy y'all{12}
// A>B::WA1XYX-15:Howdy y'all{12}34
// A>B::WA1XYX-15:Howdy y'all{toolong
// X>Y:}A>B::WA1XYX-15:Howdy y'all
// X>Y:}A>B::WA1XYX-15:Howdy y'all{12345
// X>Y:}A>B::WA1XYX-15:Howdy y'all{12}
// X>Y:}A>B::WA1XYX-15:Howdy y'all{12}34
// X>Y:}A>B::WA1XYX-15:Howdy y'all{toolong

	else {
	  // Look for message number.
	  char *pno = strchr(p->message, '{');
	  if (pno != NULL) {
	    strlcpy (A->g_message_number, pno+1, sizeof(A->g_message_number));

	    // Xastir puts a carriage return on the end.
	    char *p = strchr(A->g_message_number, '\r');
	    if (p != NULL) {
	        text_color_set(DW_COLOR_ERROR);
	        dw_printf("The APRS protocol specification says nothing about a possible carriage return after the\n");
	        dw_printf("message id.  Adding CR might prevent proper interoperability with with other applications.\n");
	        *p = '\0';
	    }

	    int mlen = strlen(A->g_message_number);
	    if (mlen < 1 || mlen > 5) {
	      text_color_set(DW_COLOR_ERROR);
	      dw_printf("Message number \"%s\" has length outside range of 1 to 5.\n", A->g_message_number);
	    }

	    // TODO: Complain if not alphanumeric.

	    char ack[8] = "";

	    if (mlen >= 3 && A->g_message_number[2] == '}') {
	      //  New (1999) style.
	      A->g_message_number[2] = '\0';
	      strlcpy (ack, A->g_message_number + 3, sizeof(ack));
	    }

	    if (strlen(ack) > 0) {
	      // With ACK.  Message number should be 2 characters.
	      snprintf (A->g_data_type_desc, sizeof(A->g_data_type_desc), "APRS Message, number \"%s\", from \"%s\" to \"%s\", with ACK for \"%s\"", A->g_message_number, A->g_src, addressee, ack);
	    }
	    else {
	      // Message number can be 1-5 characters.
	      snprintf (A->g_data_type_desc, sizeof(A->g_data_type_desc), "APRS Message, number \"%s\", from \"%s\" to \"%s\"", A->g_message_number, A->g_src, addressee);
	    }
	  }
	  else {
	    // No message number.
	    snprintf (A->g_data_type_desc, sizeof(A->g_data_type_desc), "APRS Message, with no number, from \"%s\" to \"%s\"", A->g_src, addressee);
	  }

	  A->g_message_subtype = message_subtype_message;

	  /* No location so don't use  process_comment () */

	  strlcpy (A->g_comment, p->message, sizeof(A->g_comment));
	  // Remove message number when displaying message text.
	  pno = strchr(A->g_comment, '{');
	  if (pno != NULL) {
	    *pno = '\0';
	  }
	}

}



/*------------------------------------------------------------------
 *
 * Function:	aprs_object
 *
 * Purpose:	Decode "Object Report Format"
 *
 * Inputs:	info 	- Pointer to Information field.
 *		ilen 	- Information field length.
 *
 * Outputs:	A->g_object_name, A->g_lat, A->g_lon, A->g_symbol_table, A->g_symbol_code, A->g_speed_mph, A->g_course, A->g_altitude_ft.
 *
 * Description:	Message has a 9 character object name which could be quite different than
 *		the source station.
 *
 *		This can also be a weather report when the symbol id is '_'.
 *
 * Examples:	;WA2PNU   *050457z4051.72N/07325.53W]BBS & FlexNet 145.070 MHz
 *
 *		;ActonEOC *070352z4229.20N/07125.95WoFire, EMS, Police, Heli-pad, Dial 911
 *
 *		;IRLPC494@*012112zI9*n*<ONV0   446325-146IDLE<CR>
 *
 *------------------------------------------------------------------*/

static void aprs_object (decode_aprs_t *A, unsigned char *info, int ilen) 
{

	struct aprs_object_s {
	  char dti;			/* ; */
	  char name[9];
	  char live_killed;		/* * for live or _ for killed */
	  char time_stamp[7];
	  position_t pos;
	  char comment[43]; 		/* First 7 bytes could be data extension. */
	} *p;

	struct aprs_compressed_object_s {
	  char dti;			/* ; */
	  char name[9];
	  char live_killed;		/* * for live or _ for killed */
	  char time_stamp[7];
	  compressed_position_t cpos;
	  char comment[40]; 		/* No data extension in this case. */
	} *q;


	time_t ts = 0;
	int i;


	p = (struct aprs_object_s *)info;
	q = (struct aprs_compressed_object_s *)info;

	//assert (sizeof(A->g_name) > sizeof(p->name));

	memset (A->g_name, 0, sizeof(A->g_name));
	memcpy (A->g_name, p->name, sizeof(p->name));	// copy exactly 9 bytes.

	/* Trim trailing spaces. */
	i = strlen(A->g_name) - 1;
	while (i >= 0 && A->g_name[i] == ' ') {
	  A->g_name[i--] = '\0';
	}

 	if (p->live_killed == '*')
	  strlcpy (A->g_data_type_desc, "Object", sizeof(A->g_data_type_desc));
	else if (p->live_killed == '_')
	  strlcpy (A->g_data_type_desc, "Killed Object", sizeof(A->g_data_type_desc));
	else
	  strlcpy (A->g_data_type_desc, "Object - invalid live/killed", sizeof(A->g_data_type_desc));

	ts = get_timestamp (A, p->time_stamp);

	if (isdigit((unsigned char)(p->pos.lat[0]))) 	/* Human-readable location. */
        {
	  decode_position (A, &(p->pos));

	  if (A->g_symbol_code == '_') {
	    /* Symbol code indidates it is a weather report. */
	    /* In this case, we expect 7 byte "data extension" */
	    /* for the wind direction and speed. */

	    strlcpy (A->g_data_type_desc, "Weather Report with Object", sizeof(A->g_data_type_desc));
	    weather_data (A, p->comment, TRUE);
	  } 
	  else {
	    /* Regular object. */

	    data_extension_comment (A, p->comment);
	  }
	}
	else					/* Compressed location. */
	{
	  decode_compressed_position (A, &(q->cpos));

	  if (A->g_symbol_code == '_') {
	    /* Symbol code indidates it is a weather report. */
	    /* The spec doesn't explicitly mention the combination */
	    /* of weather report and object with compressed */
	    /* position. */

	    strlcpy (A->g_data_type_desc, "Weather Report with Object", sizeof(A->g_data_type_desc));
	    weather_data (A, q->comment, FALSE);
	  } 
	  else {
	    /* Regular position report. */

	    process_comment (A, q->comment, -1);
	  }
	}

	(void)(ts);

} /* end aprs_object */


/*------------------------------------------------------------------
 *
 * Function:	aprs_item
 *
 * Purpose:	Decode "Item Report Format"
 *
 * Inputs:	info 	- Pointer to Information field.
 *		ilen 	- Information field length.
 *
 * Outputs:	A->g_object_name, A->g_lat, A->g_lon, A->g_symbol_table, A->g_symbol_code, A->g_speed_mph, A->g_course, A->g_altitude_ft.
 *
 * Description:	An "item" is very much like an "object" except 
 *
 *		-- It doesn't have a time.
 *		-- Name is a VARIABLE length 3 to 9 instead of fixed 9.
 *		-- "live" indicator is ! rather than *
 *
 * Examples:	
 *
 *------------------------------------------------------------------*/

static void aprs_item (decode_aprs_t *A, unsigned char *info, int ilen) 
{

	struct aprs_item_s {
	  char dti;			/* ')' */
	  char name[10];		/* Actually variable length 3 - 9 bytes. */
					/* DON'T refer to the rest of this structure; */
					/* the offsets will be wrong! */
					/* We make it 10 here so we don't get subscript out of bounds */
					/* warning when looking for following '!' or '_' character. */

	  char live_killed__;		/* ! for live or _ for killed */
	  position_t pos__;
	  char comment__[43]; 		/* First 7 bytes could be data extension. */
	} *p;

	struct aprs_compressed_item_s {
	  char dti;			/* ')' */
	  char name[10];		/* Actually variable length 3 - 9 bytes. */
					/* DON'T refer to the rest of this structure; */
					/* the offsets will be wrong! */

	  char live_killed__;		/* ! for live or _ for killed */
	  compressed_position_t cpos__;
	  char comment__[40]; 		/* No data extension in this case. */
	} *q;


	int i;
	char *ppos;


	p = (struct aprs_item_s *)info;
	q = (struct aprs_compressed_item_s *)info;
	(void)(q);

	memset (A->g_name, 0, sizeof(A->g_name));
	i = 0;
	while (i < 9 && p->name[i] != '!' && p->name[i] != '_') {
	  A->g_name[i] = p->name[i];
	  i++;
	  A->g_name[i] = '\0';
	}

	if (p->name[i] == '!')
	  strlcpy (A->g_data_type_desc, "Item", sizeof(A->g_data_type_desc));
	else if (p->name[i] == '_')
	  strlcpy (A->g_data_type_desc, "Killed Item", sizeof(A->g_data_type_desc));
	else {
	  if ( ! A->g_quiet) {
	    text_color_set(DW_COLOR_ERROR);
	    dw_printf("Item name too long or not followed by ! or _.\n");
	  }
	  strlcpy (A->g_data_type_desc, "Object - invalid live/killed", sizeof(A->g_data_type_desc));
	}

	ppos = p->name + i + 1;
 
	if (isdigit(*ppos)) 		/* Human-readable location. */
        {
	  decode_position (A, (position_t*) ppos);

	  data_extension_comment (A, ppos + sizeof(position_t));
	}
	else					/* Compressed location. */
	{
	  decode_compressed_position (A, (compressed_position_t*)ppos);

	  process_comment (A, ppos + sizeof(compressed_position_t), -1);
	}

}


/*------------------------------------------------------------------
 *
 * Function:	aprs_station_capabilities
 *
 * Purpose:	Decode "Station Capabilities"
 *
 * Inputs:	info 	- Pointer to Information field.
 *		ilen 	- Information field length.
 *
 * Outputs:	???
 *
 * Description:	Each capability is a TOKEN or TOKEN=VALUE pair.
 *
 *
 * Example:	<IGATE,MSG_CNT=3,LOC_CNT=49<CR>
 *		
 * Bugs:	Not implemented yet.  Treat whole thing as comment.	
 *
 *------------------------------------------------------------------*/

static void aprs_station_capabilities (decode_aprs_t *A, char *info, int ilen) 
{

	strlcpy (A->g_data_type_desc, "Station Capabilities", sizeof(A->g_data_type_desc));

	// 	process_comment() not applicable here because it 
	//	extracts information found in certain formats.

	strlcpy (A->g_comment, info+1, sizeof(A->g_comment));

} /* end aprs_station_capabilities */




/*------------------------------------------------------------------
 *
 * Function:	aprs_status_report
 *
 * Purpose:	Decode "Status Report"
 *
 * Inputs:	info 	- Pointer to Information field.
 *		ilen 	- Information field length.
 *
 * Outputs:	???
 *
 * Description:	There are 3 different formats:
 *
 *		(1)	'>'
 *			7 char - timestamp, DHM z format
 *			0-55 char - status text
 *
 *		(3)	'>'
 *			4 or 6 char - Maidenhead Locator
 *			2 char - symbol table & code
 *			' ' character
 *			0-53 char - status text	
 *
 *		(2)	'>'
 *			0-62 char - status text
 *
 *		
 *		In all cases, Beam heading and ERP can be at the
 *		very end by using '^' and two other characters.
 *		
 *
 * Examples from specification:	
 *		
 *
 *		>Net Control Center without timestamp.
 *		>092345zNet Control Center with timestamp.
 *		>IO91SX/G
 *		>IO91/G
 *		>IO91SX/- My house 		(Note the space at the start of the status text).
 *		>IO91SX/- ^B7 			Meteor Scatter beam heading = 110 degrees, ERP = 490 watts.
 *	
 *------------------------------------------------------------------*/

static void aprs_status_report (decode_aprs_t *A, char *info, int ilen) 
{
	struct aprs_status_time_s {
	  char dti;			/* > */
	  char ztime[7];		/* Time stamp ddhhmmz */
	  char comment[55]; 		
	} *pt;

	struct aprs_status_m4_s {
	  char dti;			/* > */
	  char mhead4[4];		/* 4 character Maidenhead locator. */
	  char sym_table_id;
	  char symbol_code;
	  char space;			/* Should be space after symbol code. */
	  char comment[54]; 		
	} *pm4;

	struct aprs_status_m6_s {
	  char dti;			/* > */
	  char mhead6[6];		/* 6 character Maidenhead locator. */
	  char sym_table_id;
	  char symbol_code;
	  char space;			/* Should be space after symbol code. */
	  char comment[54]; 		
	} *pm6;

	struct aprs_status_s {
	  char dti;			/* > */
	  char comment[62]; 		
	} *ps;


	strlcpy (A->g_data_type_desc, "Status Report", sizeof(A->g_data_type_desc));

	pt = (struct aprs_status_time_s *)info;
	pm4 = (struct aprs_status_m4_s *)info;
	pm6 = (struct aprs_status_m6_s *)info;
	ps = (struct aprs_status_s *)info;

/*
 * Do we have format with time?
 */
	if (isdigit(pt->ztime[0]) &&
	    isdigit(pt->ztime[1]) &&
	    isdigit(pt->ztime[2]) &&
	    isdigit(pt->ztime[3]) &&
	    isdigit(pt->ztime[4]) &&
	    isdigit(pt->ztime[5]) &&
	    pt->ztime[6] == 'z') {

	  // 	process_comment() not applicable here because it 
	  //	extracts information found in certain formats.

	  strlcpy (A->g_comment, pt->comment, sizeof(A->g_comment));
	}

/*
 * Do we have format with 6 character Maidenhead locator?
 */

	else if (get_maidenhead (A, pm6->mhead6) == 6) {

	  memset (A->g_maidenhead, 0, sizeof(A->g_maidenhead));
	  memcpy (A->g_maidenhead, pm6->mhead6, sizeof(pm6->mhead6));

	  A->g_symbol_table = pm6->sym_table_id;
	  A->g_symbol_code = pm6->symbol_code;

	  if (A->g_symbol_table != '/' && A->g_symbol_table != '\\' 
		&& ! isupper(A->g_symbol_table) && ! isdigit(A->g_symbol_table))
	  {
	    if ( ! A->g_quiet) {
	      text_color_set(DW_COLOR_ERROR);
	      dw_printf("Invalid symbol table code '%c' not one of / \\ A-Z 0-9\n", A->g_symbol_table);	
	    }
	    A->g_symbol_table = '/';
	  }

	  if (pm6->space != ' ' && pm6->space != '\0') {
	    if ( ! A->g_quiet) {
	      text_color_set(DW_COLOR_ERROR);
	      dw_printf("Error: Found '%c' instead of space required after symbol code.\n", pm6->space);
	    }	
	  }

	  // 	process_comment() not applicable here because it 
	  //	extracts information found in certain formats.

	  strlcpy (A->g_comment, pm6->comment, sizeof(A->g_comment));
	}

/*
 * Do we have format with 4 character Maidenhead locator?
 */
	else if (get_maidenhead (A, pm4->mhead4) == 4) {

	  memset (A->g_maidenhead, 0, sizeof(A->g_maidenhead));
	  memcpy (A->g_maidenhead, pm4->mhead4, sizeof(pm4->mhead4));

	  A->g_symbol_table = pm4->sym_table_id;
	  A->g_symbol_code = pm4->symbol_code;

	  if (A->g_symbol_table != '/' && A->g_symbol_table != '\\' 
		&& ! isupper(A->g_symbol_table) && ! isdigit(A->g_symbol_table))
	  {
	    if ( ! A->g_quiet) {
	      text_color_set(DW_COLOR_ERROR);
	      dw_printf("Invalid symbol table code '%c' not one of / \\ A-Z 0-9\n", A->g_symbol_table);	
	    }
	    A->g_symbol_table = '/';
	  }

	  if (pm4->space != ' ' && pm4->space != '\0') {
	    if ( ! A->g_quiet) {
	      text_color_set(DW_COLOR_ERROR);
	      dw_printf("Error: Found '%c' instead of space required after symbol code.\n", pm4->space);
	    }
	  }

	  // 	process_comment() not applicable here because it 
	  //	extracts information found in certain formats.

	  strlcpy (A->g_comment, pm4->comment, sizeof(A->g_comment));
	}

/*
 * Whole thing is status text.
 */
	else {
	  strlcpy (A->g_comment, ps->comment, sizeof(A->g_comment));
	}


/*
 * Last 3 characters can represent beam heading and ERP.
 */

	if (strlen(A->g_comment) >= 3) {
	  char *hp = A->g_comment + strlen(A->g_comment) - 3;
	
	  if (*hp == '^') {

	    char h = hp[1];
	    char p = hp[2];
	    int beam = -1;
	    int erp = -1;

	    if (h >= '0' && h <= '9') {
	      beam = (h - '0') * 10;
	    }
	    else if (h >= 'A' && h <= 'Z') {
	      beam = (h - 'A') * 10 + 100;
	    }

	    if (p >= '1' && p <= 'K') {
	      erp = (p - '0') * (p - '0') * 10;
	    }

	// TODO (low):  put result somewhere.
	// could use A->g_directivity and need new variable for erp.

	    *hp = '\0';

	    (void)(beam);
	    (void)(erp);
	  }
	}

} /* end aprs_status_report */


/*------------------------------------------------------------------
 *
 * Function:	aprs_general_query
 *
 * Purpose:	Decode "General Query" for all stations.
 *
 * Inputs:	info 	- Pointer to Information field.  First character should be "?".
 *		ilen 	- Information field length.
 *		quiet	- suppress error messages.
 *
 * Outputs:	A	- Decoded packet structure
 *				A->g_query_type
 *				A->g_query_lat		(optional)
 *				A->g_query_lon		(optional)
 *				A->g_query_radius	(optional)
 *
 * Description:	Formats are:
 *	
 *			?query?
 *			?query?lat,long,radius
 *
 *		'query' is one of APRS, IGATE, WX, ...
 *		optional footprint, in degrees and miles radius, means only
 *			those in the specified circle should respond.
 *
 * Examples from specification, Chapter 15:		
 *
 *		?APRS?
 *		?APRS? 34.02,-117.15,0200
 *		?IGATE?
 *	
 *------------------------------------------------------------------*/

/*
https://groups.io/g/direwolf/topic/95961245#7357

What APRS queries should DireWolf respond to? Well, it should be configurable whether it responds to queries at all, in case some other application is using DireWolf as a dumb TNC (KISS or AGWPE style) and wants to handle the queries itself.

Assuming query responding is enabled, the following broadcast queries should be supported (if the corresponding data is configured in DireWolf):

?APRS (I am an APRS station)
?IGATE (I am operating as a I-gate)
?WX (I am providing local weather data in my beacon)

*/


static void aprs_general_query (decode_aprs_t *A, char *info, int ilen, int quiet) 
{
	char *q2;
	char *p;
	char *tok;
	char stemp[256];		
	double lat, lon;
	float radius;

	strlcpy (A->g_data_type_desc, "General Query", sizeof(A->g_data_type_desc));

/*
 * First make a copy because we will modify it while parsing it.
 */

	strlcpy (stemp, info, sizeof(stemp));

/*
 * There should be another "?" after the query type.
 */
	q2 = strchr(stemp+1, '?');
	if (q2 == NULL) {
	  if ( ! A->g_quiet) {
	    text_color_set(DW_COLOR_ERROR);
	    dw_printf("General Query must have ? after the query type.\n");
	  }
	  return; 
	}

	*q2 = '\0';
	strlcpy (A->g_query_type, stemp+1, sizeof(A->g_query_type));

// TODO: remove debug

	text_color_set(DW_COLOR_DEBUG);
	dw_printf("DEBUG: General Query type = \"%s\"\n", A->g_query_type);

	p = q2 + 1;
	if (strlen(p) == 0) {
	  return;
	}

/*
 * Try to extract footprint.
 * Spec says positive coordinate would be preceded by space
 * and radius must be exactly 4 digits.  We are more forgiving. 
 */
	tok = strsep(&p, ",");
	if (tok != NULL) {
	  lat = atof(tok);
	  tok = strsep(&p, ",");
	  if (tok != NULL) {
	    lon = atof(tok);
	    tok = strsep(&p, ",");
	    if (tok != NULL) {
	      radius = atof(tok);

	      if (lat < -90 || lat > 90) {
	        if ( ! A->g_quiet) {
	          text_color_set(DW_COLOR_ERROR);
	          dw_printf("Invalid latitude for General Query footprint.\n");
	        }
	        return; 
	      }

	      if (lon < -180 || lon > 180) {
	        if ( ! A->g_quiet) {
	          text_color_set(DW_COLOR_ERROR);
	          dw_printf("Invalid longitude for General Query footprint.\n");
	        }
	        return; 
	      }

	      if (radius <= 0 || radius > 9999) {
	        if ( ! A->g_quiet) {
	          text_color_set(DW_COLOR_ERROR);
	          dw_printf("Invalid radius for General Query footprint.\n");
	        }
	        return; 
	      }

	      A->g_footprint_lat = lat;
	      A->g_footprint_lon = lon;
	      A->g_footprint_radius = radius;
	    }
	    else {
	      if ( ! A->g_quiet) {
	        text_color_set(DW_COLOR_ERROR);
	        dw_printf("Can't get radius for General Query footprint.\n");
	      }
	      return;
	    }
	  }
	  else {
	    if ( ! A->g_quiet) {
	      text_color_set(DW_COLOR_ERROR);
	      dw_printf("Can't get longitude for General Query footprint.\n");
	    }
	    return;
	  }
	}
	else {
	  if ( ! A->g_quiet) {
	    text_color_set(DW_COLOR_ERROR);
	    dw_printf("Can't get latitude for General Query footprint.\n");
	  }
	  return;
	}
	
// TODO: remove debug

	text_color_set(DW_COLOR_DEBUG);
	dw_printf("DEBUG: General Query footprint = %.6f %.6f %.2f\n", lat, lon, radius);


} /* end aprs_general_query */



/*------------------------------------------------------------------
 *
 * Function:	aprs_directed_station_query
 *
 * Purpose:	Decode "Directed Station Query" aimed at specific station.
 *		This is actually a special format of the more general "message."
 *
 * Inputs:	addressee	- To whom it is directed.
 *				  Redundant because it is already in A->addressee.
 *
 *		query	 	- What's left over after ":addressee:?" in info part.
 *
 *		quiet		- suppress error messages.
 *
 * Outputs:	A	- Decoded packet structure
 *				A->g_query_type
 *				A->g_query_callsign	(optional)
 *
 * Description:	The caller has already removed the :addressee:? part so we are left 
 *		with a query type of exactly 5 characters and optional "callsign 
 *		of heard station."
 *	
 * Examples from specification, Chapter 15.   Our "query" argument.	
 *
 *		:KH2Z     :?APRSD		APRSD
 *		:KH2Z     :?APRSHVN0QBF     	APRSHVN0QBF
 *		:KH2Z     :?APRST		APRST
 *		:KH2Z     :?PING?		PING?
 *	
 *		"PING?" contains "?" only to pad it out to exactly 5 characters.
 *
 *------------------------------------------------------------------*/

/*
https://groups.io/g/direwolf/topic/95961245#7357

The following directed queries (sent as bodies of APRS text messages) would also be useful (if corresponding data configured):

?APRSP (force my current beacon)
?APRST and ?PING (trace my path to requestor)
?APRSD (all stations directly heard [no digipeat hops] by local station)
?APRSO (any Objects/Items originated by this station)
?APRSH (how often or how many times the specified 3rd station was heard by the queried station)
?APRSS (immediately send the Status message if configured) (can DireWolf do Status messages?)

Lynn KJ4ERJ and I have implemented a non-standard query which might be useful:

?VER (send the human-readable software version of the queried station)

Hope this is useful. It's just my $.02.

Andrew, KA2DDO
author of YAAC
*/

static void aprs_directed_station_query (decode_aprs_t *A, char *addressee, char *query, int quiet)
{
	//char query_type[20];		/* Does the query type always need to be exactly 5 characters? */
					/* If not, how would we know where the extra optional information starts? */

	//char callsign[AX25_MAX_ADDR_LEN];

	//if (strlen(query) < 5) ...


}  /* end aprs_directed_station_query */



/*------------------------------------------------------------------
 *
 * Function:	aprs_Telemetry
 *
 * Purpose:	Decode "Telemetry"
 *
 * Inputs:	info 	- Pointer to Information field.
 *		ilen 	- Information field length.
 *		quiet	- suppress error messages.
 *
 * Outputs:	A->g_telemetry
 *		A->g_comment
 *
 * Description:	TBD.
 *
 * Examples from specification:	
 *		
 *
 *		TBD
 *	
 *------------------------------------------------------------------*/

static void aprs_telemetry (decode_aprs_t *A, char *info, int ilen, int quiet) 
{

	strlcpy (A->g_data_type_desc, "Telemetry", sizeof(A->g_data_type_desc));

	telemetry_data_original (A->g_src, info, quiet, A->g_telemetry, sizeof(A->g_telemetry), A->g_comment, sizeof(A->g_comment));


} /* end aprs_telemetry */


/*------------------------------------------------------------------
 *
 * Function:	aprs_user_defined
 *
 * Purpose:	Decode user defined data.
 *
 * Inputs:	info 	- Pointer to Information field.
 *		ilen 	- Information field length.
 *
 * Description:	APRS Protocol Specification, Chapter 18
 *		User IDs allocated here:  http://www.aprs.org/aprs11/expfmts.txt
 *		
 *------------------------------------------------------------------*/

static void aprs_user_defined (decode_aprs_t *A, char *info, int ilen)
{
	if (strncmp(info, "{tt", 3) == 0 ||		// Historical.
		strncmp(info, "{DT", 3) == 0) {		// Official after registering {D*
	  aprs_raw_touch_tone (A, info, ilen);
	}
	else if (strncmp(info, "{mc", 3) == 0 ||	// Historical.
		strncmp(info, "{DM", 3) == 0) {		// Official after registering {D*
	  aprs_morse_code (A, info, ilen);
	}
	else if (info[0] == '{' && info[1] == USER_DEF_USER_ID && info[2] == USER_DEF_TYPE_AIS) {
	  double lat, lon;
	  float knots, course;
	  float alt_meters;

	  ais_parse (info+3, 0, A->g_data_type_desc, sizeof(A->g_data_type_desc), A->g_name, sizeof(A->g_name),
			&lat, &lon, &knots, &course, &alt_meters, &(A->g_symbol_table), &(A->g_symbol_code),
			A->g_comment, sizeof(A->g_comment));

	  A->g_lat = lat;
	  A->g_lon = lon;
	  A->g_speed_mph =  DW_KNOTS_TO_MPH(knots);
	  A->g_course = course;
	  A->g_altitude_ft = DW_METERS_TO_FEET(alt_meters);
	  strcpy (A->g_mfr, "");
	}
	else if (strncmp(info, "{{", 2) == 0) {
	  snprintf (A->g_data_type_desc, sizeof(A->g_data_type_desc), "User-Defined Experimental");
	}
	else {
	  snprintf (A->g_data_type_desc, sizeof(A->g_data_type_desc), "User-Defined Data");
	}

} /* end aprs_user_defined */


/*------------------------------------------------------------------
 *
 * Function:	aprs_raw_touch_tone
 *
 * Purpose:	Decode raw touch tone datA->
 *
 * Inputs:	info 	- Pointer to Information field.
 *		ilen 	- Information field length.
 *
 * Description:	Touch tone data is converted to a packet format
 *		so it can be conveyed to an application for processing.
 *
 * 		This is not part of the APRS standard.	
 *		
 *------------------------------------------------------------------*/

static void aprs_raw_touch_tone (decode_aprs_t *A, char *info, int ilen) 
{

	strlcpy (A->g_data_type_desc, "Raw Touch Tone Data", sizeof(A->g_data_type_desc));

	/* Just copy the info field without the message type. */

	if (*info == '{') 
	  strlcpy (A->g_comment, info+3, sizeof(A->g_comment));
	else
	  strlcpy (A->g_comment, info+1, sizeof(A->g_comment));


} /* end aprs_raw_touch_tone */



/*------------------------------------------------------------------
 *
 * Function:	aprs_morse_code
 *
 * Purpose:	Convey message in packet format to be transmitted as 
 *		Morse Code.
 *
 * Inputs:	info 	- Pointer to Information field.
 *		ilen 	- Information field length.
 *
 * Description:	This is not part of the APRS standard.	
 *		
 *------------------------------------------------------------------*/

static void aprs_morse_code (decode_aprs_t *A, char *info, int ilen) 
{

	strlcpy (A->g_data_type_desc, "Morse Code Data", sizeof(A->g_data_type_desc));

	/* Just copy the info field without the message type. */

	if (*info == '{') 
	  strlcpy (A->g_comment, info+3, sizeof(A->g_comment));
	else
	  strlcpy (A->g_comment, info+1, sizeof(A->g_comment));


} /* end aprs_morse_code */


/*------------------------------------------------------------------
 *
 * Function:	aprs_ll_pos_time
 *
 * Purpose:	Decode weather report without a position.
 *
 * Inputs:	info 	- Pointer to Information field.
 *		ilen 	- Information field length.
 *
 * Outputs:	A->g_symbol_table, A->g_symbol_code.
 *
 * Description:	Type identifier '_' is a weather report without a position.
 *
 *------------------------------------------------------------------*/



static void aprs_positionless_weather_report (decode_aprs_t *A, unsigned char *info, int ilen) 
{

	struct aprs_positionless_weather_s {
	  char dti;			/* _ */
	  char time_stamp[8];		/* MDHM format */
	  char comment[99]; 		
	} *p;


	strlcpy (A->g_data_type_desc, "Positionless Weather Report", sizeof(A->g_data_type_desc));

	//time_t ts = 0;


	p = (struct aprs_positionless_weather_s *)info;
	
	// not yet implemented for 8 character format // ts = get_timestamp (A, p->time_stamp);

	weather_data (A, p->comment, FALSE);
}


/*------------------------------------------------------------------
 *
 * Function:	weather_data
 *
 * Purpose:	Decode weather data in position or object report.
 *
 * Inputs:	info 	- Pointer to first byte after location
 *			  and symbol code.
 *
 *		wind_prefix 	- Expecting leading wind info
 *				  for human-readable location.
 *				  (Currently ignored.  We are very
 *				  forgiving in what is accepted.)
 * TODO: call this context instead and have 3 enumerated values.
 *
 * Global In:	A->g_course	- Wind info for compressed location.
 *		A->g_speed_mph
 *
 * Outputs:	A->g_weather
 *
 * Description:	Extract weather details and format into a comment.
 *
 *		For human-readable locations, we expect wind direction
 *		and speed in a format like this:  999/999.
 *		For compressed location, this has already been 
 * 		processed and put in A->g_course and A->g_speed_mph.
 *		Otherwise, for positionless weather data, the 
 *		wind is in the form c999s999.
 *
 * References:	APRS Weather specification comments.
 *		http://aprs.org/aprs11/spec-wx.txt
 *
 *		Weather updates to the spec.
 *		http://aprs.org/aprs12/weather-new.txt
 *
 * Examples:
 *	
 *	_10090556c220s004g005t077r000p000P000h50b09900wRSW
 *	!4903.50N/07201.75W_220/004g005t077r000p000P000h50b09900wRSW
 *	!4903.50N/07201.75W_220/004g005t077r000p000P000h50b.....wRSW
 *	@092345z4903.50N/07201.75W_220/004g005t-07r000p000P000h50b09900wRSW
 *	=/5L!!<*e7_7P[g005t077r000p000P000h50b09900wRSW
 *	@092345z/5L!!<*e7_7P[g005t077r000p000P000h50b09900wRSW
 *	;BRENDA   *092345z4903.50N/07201.75W_220/004g005b0990
 *
 *------------------------------------------------------------------*/

static int getwdata (char **wpp, char ch, int dlen, float *val) 
{
	char stemp[8];	// larger than maximum dlen.
	int i;


	//dw_printf("debug: getwdata (wp=%p, ch=%c, dlen=%d)\n", *wpp, ch, dlen);

	*val = G_UNKNOWN;

	assert (dlen >= 2 && dlen <= 6);

	if (**wpp != ch) {
	  /* Not specified element identifier. */
	  return (0);	
	}
	
	if (strncmp((*wpp)+1, "......", dlen) == 0 || strncmp((*wpp)+1, "      ", dlen) == 0) {
	  /* Field present, unknown value */
	  *wpp += 1 + dlen;
	  return (1); 
	}

	/* Data field can contain digits, decimal point, leading negative. */

	for (i=1; i<=dlen; i++) {
	  if ( ! isdigit((*wpp)[i]) && (*wpp)[i] != '.' && (*wpp)[i] != '-' ) {
	    return(0);
	  }
	} 

	memset (stemp, 0, sizeof(stemp));
	memcpy (stemp, (*wpp)+1, dlen);
	*val = atof(stemp);

	//dw_printf("debug: getwdata returning %f\n", *val);

	*wpp += 1 + dlen;
	return (1); 
}	

static void weather_data (decode_aprs_t *A, char *wdata, int wind_prefix) 
{
	int n;
	float fval;
	char *wp = wdata;
	int keep_going;

	
	if (wp[3] == '/')
	{
	  if (sscanf (wp, "%3d", &n))
	  {
	    // Data Extension format.
	    // Fine point:  Officially, should be values of 001-360.
	    // "000" or "..." or "   " means unknown. 
	    // In practice we see do see "000" here.
	    A->g_course = n;
	  }
	  if (sscanf (wp+4, "%3d", &n))
	  {
	    A->g_speed_mph = DW_KNOTS_TO_MPH(n);  /* yes, in knots */
	  }
	  wp += 7;
	}
	else if ( A->g_speed_mph == G_UNKNOWN) {

	  if ( ! getwdata (&wp, 'c', 3, &A->g_course)) {
	    if ( ! A->g_quiet) {
	      text_color_set(DW_COLOR_ERROR);
	      dw_printf("Didn't find wind direction in form c999.\n");
	    }
	  }
	  if ( ! getwdata (&wp, 's', 3, &A->g_speed_mph)) {	/* MPH here */
	    if ( ! A->g_quiet) {
	      text_color_set(DW_COLOR_ERROR);
	      dw_printf("Didn't find wind speed in form s999.\n");
	    }
	  }
	}

// At this point, we should have the wind direction and speed
// from one of three methods.

	if (A->g_speed_mph != G_UNKNOWN) {

	  snprintf (A->g_weather, sizeof(A->g_weather), "wind %.1f mph", A->g_speed_mph);
	  if (A->g_course != G_UNKNOWN) {
	    char ctemp[40];
	    snprintf (ctemp, sizeof(ctemp), ", direction %.0f", A->g_course);
	    strlcat (A->g_weather, ctemp, sizeof(A->g_weather));
	  }
	}

	/* We don't want this to show up on the location line. */
	A->g_speed_mph = G_UNKNOWN;
	A->g_course = G_UNKNOWN;

/*
 * After the mandatory wind direction and speed (in 1 of 3 formats), the
 * next two must be in fixed positions:
 * - gust (peak in mph last 5 minutes)
 * - temperature, degrees F, can be negative e.g. -01
 */
	if (getwdata (&wp, 'g', 3, &fval)) {
	  if (fval != G_UNKNOWN) {
	    char ctemp[40];
	    snprintf (ctemp, sizeof(ctemp), ", gust %.0f", fval);
	    strlcat (A->g_weather, ctemp, sizeof(A->g_weather));
	  }
	}
	else {
	  if ( ! A->g_quiet) {
	    text_color_set(DW_COLOR_ERROR);
	    dw_printf("Didn't find wind gust in form g999.\n");
	  }
	}

	if (getwdata (&wp, 't', 3, &fval)) {
	  if (fval != G_UNKNOWN) {
	    char ctemp[40];
	    snprintf (ctemp, sizeof(ctemp), ", temperature %.0f", fval);
	    strlcat (A->g_weather, ctemp, sizeof(A->g_weather));
	  }
	}
	else {
	  if ( ! A->g_quiet) {
	    text_color_set(DW_COLOR_ERROR);
	    dw_printf("Didn't find temperature in form t999.\n");
	  }
	}

/*
 * Now pick out other optional fields in any order.
 */
	keep_going = 1;
	while (keep_going) {

	  if (getwdata (&wp, 'r', 3, &fval)) {	

	/* r = rainfall, 1/100 inch, last hour */

	    if (fval != G_UNKNOWN) {
	      char ctemp[40];
	      snprintf (ctemp, sizeof(ctemp), ", rain %.2f in last hour", fval / 100.);
	      strlcat (A->g_weather, ctemp, sizeof(A->g_weather));
	    }
	  }
	  else if (getwdata (&wp, 'p', 3, &fval)) {	

	/* p = rainfall, 1/100 inch, last 24 hours */

	    if (fval != G_UNKNOWN) {
	      char ctemp[40];
	      snprintf (ctemp, sizeof(ctemp), ", rain %.2f in last 24 hours", fval / 100.);
	      strlcat (A->g_weather, ctemp, sizeof(A->g_weather));
	    }
	  }
	  else if (getwdata (&wp, 'P', 3, &fval)) {	

	/* P = rainfall, 1/100 inch, since midnight */

	    if (fval != G_UNKNOWN) {
	      char ctemp[40];
	      snprintf (ctemp, sizeof(ctemp), ", rain %.2f since midnight", fval / 100.);
	      strlcat (A->g_weather, ctemp, sizeof(A->g_weather));
	    }
	  }
	  else if (getwdata (&wp, 'h', 2, &fval)) {	

	/* h = humidity %, 00 means 100%  */

	    if (fval != G_UNKNOWN) {
	      char ctemp[30];
	      if (fval == 0) fval = 100;
	      snprintf (ctemp, sizeof(ctemp), ", humidity %.0f", fval);
	      strlcat (A->g_weather, ctemp, sizeof(A->g_weather));
	    }
	  }
	  else if (getwdata (&wp, 'b', 5, &fval)) {	

	/* b = barometric presure (tenths millibars / tenths of hPascal)  */
	/* Here, display as inches of mercury. */

	    if (fval != G_UNKNOWN) {
	      char ctemp[40];
	      fval = DW_MBAR_TO_INHG(fval * 0.1);
	      snprintf (ctemp, sizeof(ctemp), ", barometer %.2f", fval);
	      strlcat (A->g_weather, ctemp, sizeof(A->g_weather));
	    }
	  }
	  else if (getwdata (&wp, 'L', 3, &fval)) {	

	/* L = Luminosity, watts/ sq meter, 000-999  */
	
	    if (fval != G_UNKNOWN) {
	      char ctemp[40];
	      snprintf (ctemp, sizeof(ctemp), ", %.0f watts/m^2", fval);
	      strlcat (A->g_weather, ctemp, sizeof(A->g_weather));
	    }
	  }
	  else if (getwdata (&wp, 'l', 3, &fval)) {	

	/* l = Luminosity, watts/ sq meter, 1000-1999  */
	
	    if (fval != G_UNKNOWN) {
	      char ctemp[40];
	      snprintf (ctemp, sizeof(ctemp), ", %.0f watts/m^2", fval + 1000);
	      strlcat (A->g_weather, ctemp, sizeof(A->g_weather));
	    }
	  }
	  else if (getwdata (&wp, 's', 3, &fval)) {	

	/* s = Snowfall in last 24 hours, inches  */
	/* Data can have decimal point so we don't have to worry about scaling. */
	/* 's' is also used by wind speed but that must be in a fixed */
	/* position in the message so there is no confusion. */
	
	    if (fval != G_UNKNOWN) {
	      char ctemp[40];
	      snprintf (ctemp, sizeof(ctemp), ", %.1f snow in 24 hours", fval);
	      strlcat (A->g_weather, ctemp, sizeof(A->g_weather));
	    }
	  }
	  else if (getwdata (&wp, 's', 3, &fval)) {	

	/* # = Raw rain counter  */
	
	    if (fval != G_UNKNOWN) {
	      char ctemp[40];
	      snprintf (ctemp, sizeof(ctemp), ", raw rain counter %.f", fval);
	      strlcat (A->g_weather, ctemp, sizeof(A->g_weather));
	    }
	  }
	  else if (getwdata (&wp, 'X', 3, &fval)) {	

	/* X = Nuclear Radiation.  */
	/* Encoded as two significant digits and order of magnitude */
	/* like resistor color code. */

// TODO: decode this properly
	
	    if (fval != G_UNKNOWN) {
	      char ctemp[40];
	      snprintf (ctemp, sizeof(ctemp), ", nuclear Radiation %.f", fval);
	      strlcat (A->g_weather, ctemp, sizeof(A->g_weather));
	    }
	  }

// TODO: add new flood level, battery voltage, etc.

	  else {
	    keep_going = 0;
	  }
	}

/*
 * We should be left over with:
 * - one character for software.
 * - two to four characters for weather station type.
 * Examples: tU2k, wRSW
 *
 * But few people follow the protocol spec here.  Instead more often we see things like:
 *  sunny/WX
 *  / {UIV32N}
 */

	strlcat (A->g_weather, ", \"", sizeof(A->g_weather));
	strlcat (A->g_weather, wp, sizeof(A->g_weather));
/*
 * Drop any CR / LF character at the end.
 */
	n = strlen(A->g_weather);
	if (n >= 1 && A->g_weather[n-1] == '\n') {
	  A->g_weather[n-1] = '\0';
	}

	n = strlen(A->g_weather);
	if (n >= 1 && A->g_weather[n-1] == '\r') {
	  A->g_weather[n-1] = '\0';
	}

	strlcat (A->g_weather, "\"", sizeof(A->g_weather));

	return;

} /* end weather_data */


/*------------------------------------------------------------------
 *
 * Function:	aprs_ultimeter
 *
 * Purpose:	Decode Peet Brothers ULTIMETER Weather Station Info.
 *
 * Inputs:	info 	- Pointer to Information field.
 *		ilen 	- Information field length.
 *
 * Outputs:	A->g_weather
 *
 * Description:	http://www.peetbros.com/shop/custom.aspx?recid=7 
 *
 * 		There are two different data formats in use.
 *		One begins with $ULTW and is called "Packet Mode."  Example:
 *
 *		$ULTW009400DC00E21B8027730008890200010309001E02100000004C<CR><LF>
 *
 *		The other begins with !! and is called "logging mode."  Example:
 *
 *		!!000000A600B50000----------------001C01D500000017<CR><LF>
 *
 *
 * Bugs:	Implementation is incomplete.
 *		The example shown in the APRS protocol spec has a couple "----"
 *		fields in the $ULTW message.  This should be rewritten to handle
 *		each field separately to deal with missing pieces.
 *
 *------------------------------------------------------------------*/

static void aprs_ultimeter (decode_aprs_t *A, char *info, int ilen) 
{

				// Header = $ULTW 
				// Data Fields 
	short h_windpeak;	// 1. Wind Speed Peak over last 5 min. (0.1 kph) 
	short h_wdir;		// 2. Wind Direction of Wind Speed Peak (0-255) 
	short h_otemp;		// 3. Current Outdoor Temp (0.1 deg F) 
	short h_totrain;	// 4. Rain Long Term Total (0.01 in.) 
	short h_baro;		// 5. Current Barometer (0.1 mbar) 
	short h_barodelta;	// 6. Barometer Delta Value(0.1 mbar) 
	short h_barocorrl;	// 7. Barometer Corr. Factor(LSW) 
	short h_barocorrm;	// 8. Barometer Corr. Factor(MSW) 
	short h_ohumid;		// 9. Current Outdoor Humidity (0.1%) 
	short h_date;		// 10. Date (day of year) 
	short h_time;		// 11. Time (minute of day) 
	short h_raintoday;	// 12. Today's Rain Total (0.01 inches)* 
	short h_windave;	// 13. 5 Minute Wind Speed Average (0.1kph)* 
				// Carriage Return & Line Feed
				// *Some instruments may not include field 13, some may 
				// not include 12 or 13. 
				// Total size: 44, 48 or 52 characters (hex digits) + 
				// header, carriage return and line feed. 

	int n;

	strlcpy (A->g_data_type_desc, "Ultimeter", sizeof(A->g_data_type_desc));

	if (*info == '$')
 	{
	  n = sscanf (info+5, "%4hx%4hx%4hx%4hx%4hx%4hx%4hx%4hx%4hx%4hx%4hx%4hx%4hx",
			&h_windpeak,		
			&h_wdir,		
			&h_otemp,
			&h_totrain,		
			&h_baro,		
			&h_barodelta,	
			&h_barocorrl,	
			&h_barocorrm,	
			&h_ohumid,		 
			&h_date,		
			&h_time,		
			&h_raintoday,	 	// not on some models.
			&h_windave);		// not on some models.

	  if (n >= 11 && n <= 13) {

	    float windpeak, wdir, otemp, baro, ohumid;

	    windpeak = DW_KM_TO_MILES(h_windpeak * 0.1);
	    wdir = (h_wdir & 0xff) * 360. / 256.;
	    otemp = h_otemp * 0.1;
	    baro = DW_MBAR_TO_INHG(h_baro * 0.1);
	    ohumid = h_ohumid * 0.1;
	  
	    snprintf (A->g_weather, sizeof(A->g_weather), "wind %.1f mph, direction %.0f, temperature %.1f, barometer %.2f, humidity %.0f",
			windpeak, wdir, otemp, baro, ohumid);
	  }
	}

	
		// Header = !! 
		// Data Fields 
		// 1. Wind Speed (0.1 kph) 
		// 2. Wind Direction (0-255) 
		// 3. Outdoor Temp (0.1 deg F) 
		// 4. Rain* Long Term Total (0.01 inches)  
		// 5. Barometer (0.1 mbar) 	[ can be ---- ]
		// 6. Indoor Temp (0.1 deg F) 	[ can be ---- ]
		// 7. Outdoor Humidity (0.1%) 	[ can be ---- ]
		// 8. Indoor Humidity (0.1%) 	[ can be ---- ]
		// 9. Date (day of year) 
		// 10. Time (minute of day) 
		// 11. Today's Rain Total (0.01 inches)* 
		// 12. 1 Minute Wind Speed Average (0.1kph)* 
		// Carriage Return & Line Feed 
		//
		// *Some instruments may not include field 12, some may not include 11 or 12. 
		// Total size: 40, 44 or 48 characters (hex digits) + header, carriage return and line feed

	if (*info == '!')
 	{
	  n = sscanf (info+2, "%4hx%4hx%4hx%4hx",
			&h_windpeak,		
			&h_wdir,		
			&h_otemp,
			&h_totrain);

	  if (n == 4) {

	    float windpeak, wdir, otemp;

	    windpeak = DW_KM_TO_MILES(h_windpeak * 0.1);
	    wdir = (h_wdir & 0xff) * 360. / 256.;
	    otemp = h_otemp * 0.1;
	  
	    snprintf (A->g_weather, sizeof(A->g_weather), "wind %.1f mph, direction %.0f, temperature %.1f\n",
			windpeak, wdir, otemp);
	  }

	}

} /* end aprs_ultimeter */



/*------------------------------------------------------------------
 *
 * Function:	decode_position
 *
 * Purpose:	Decode the position & symbol information common to many message formats.
 *
 * Inputs:	ppos 	- Pointer to position & symbol fields.
 *
 * Returns:	A->g_lat
 *		A->g_lon
 *		A->g_symbol_table
 *		A->g_symbol_code
 *
 * Description:	This provides resolution of about 60 feet.
 *		This can be improved by using !DAO! in the comment.
 *
 *------------------------------------------------------------------*/


static void decode_position (decode_aprs_t *A, position_t *ppos)
{

	  A->g_lat = get_latitude_8 (ppos->lat, A->g_quiet);
	  A->g_lon = get_longitude_9 (ppos->lon, A->g_quiet);

	  A->g_symbol_table = ppos->sym_table_id;
	  A->g_symbol_code = ppos->symbol_code;
}

/*------------------------------------------------------------------
 *
 * Function:	decode_compressed_position
 *
 * Purpose:	Decode the compressed position & symbol information common to many message formats.
 *
 * Inputs:	ppos 	- Pointer to compressed position & symbol fields.
 *
 * Returns:	A->g_lat
 *		A->g_lon
 *		A->g_symbol_table
 *		A->g_symbol_code
 *
 *		One of the following:
 *			A->g_course & A->g_speeed
 *			A->g_altitude_ft
 *			A->g_range
 *
 * Description:	The compressed position provides resolution of around ???
 *		This also includes course/speed or altitude.
 *
 *		It contains 13 bytes of the format:
 *
 *			symbol table	/, \, or overlay A-Z, a-j is mapped into 0-9
 *
 *			yyyy		Latitude, base 91.
 * 
 *			xxxx		Longitude, base 91.
 *
 *			symbol code
 *
 *			cs		Course/Speed or altitude.
 *
 *			t		Various "type" info.
 *
 *------------------------------------------------------------------*/


static void decode_compressed_position (decode_aprs_t *A, compressed_position_t *pcpos)
{
	if (isdigit91(pcpos->y[0]) && isdigit91(pcpos->y[1]) && isdigit91(pcpos->y[2]) && isdigit91(pcpos->y[3]))
	{
	  A->g_lat = 90 - ((pcpos->y[0]-33)*91*91*91 + (pcpos->y[1]-33)*91*91 + (pcpos->y[2]-33)*91 + (pcpos->y[3]-33)) / 380926.0;
	}
	else
 	{
	  if ( ! A->g_quiet) {
	    text_color_set(DW_COLOR_ERROR);
	    dw_printf("Invalid character in compressed latitude.  Must be in range of '!' to '{'.\n");
	  }
	  A->g_lat = G_UNKNOWN;
	}
	  
	if (isdigit91(pcpos->x[0]) && isdigit91(pcpos->x[1]) && isdigit91(pcpos->x[2]) && isdigit91(pcpos->x[3]))
	{
	  A->g_lon = -180 + ((pcpos->x[0]-33)*91*91*91 + (pcpos->x[1]-33)*91*91 + (pcpos->x[2]-33)*91 + (pcpos->x[3]-33)) / 190463.0;
	}
	else 
	{
	  if ( ! A->g_quiet) {
	    text_color_set(DW_COLOR_ERROR);
	    dw_printf("Invalid character in compressed longitude.  Must be in range of '!' to '{'.\n");
	  }
	  A->g_lon = G_UNKNOWN;
	}

	if (pcpos->sym_table_id == '/' || pcpos->sym_table_id == '\\' || isupper((int)(pcpos->sym_table_id))) {
	  /* primary or alternate or alternate with upper case overlay. */
	  A->g_symbol_table = pcpos->sym_table_id;
   	}
	else if (pcpos->sym_table_id >= 'a' && pcpos->sym_table_id <= 'j') {
	  /* Lower case a-j are used to represent overlay characters 0-9 */
	  /* because a digit here would mean normal (non-compressed) location. */
	  A->g_symbol_table = pcpos->sym_table_id - 'a' + '0';
	}
	else {
	  if ( ! A->g_quiet) {
	    text_color_set(DW_COLOR_ERROR);
	    dw_printf("Invalid symbol table id for compressed position.\n");
	  }
	  A->g_symbol_table = '/';
	}

	A->g_symbol_code = pcpos->symbol_code;

	if (pcpos->c == ' ') {
	  ; /* ignore other two bytes */
	}
	else if (((pcpos->t - 33) & 0x18) == 0x10) {
	  A->g_altitude_ft = pow(1.002, (pcpos->c - 33) * 91 + pcpos->s - 33);
	}
	else if (pcpos->c == '{')
	{
	  A->g_range = 2.0 * pow(1.08, pcpos->s - 33);
	}
	else if (pcpos->c >= '!' && pcpos->c <= 'z')
	{
	  /* For a weather station, this is wind information. */
	  A->g_course = (pcpos->c - 33) * 4;
	  A->g_speed_mph = DW_KNOTS_TO_MPH(pow(1.08, pcpos->s - 33) - 1.0);
	}

}


/*------------------------------------------------------------------
 *
 * Function:	get_latitude_8
 *
 * Purpose:	Convert 8 byte latitude encoding to degrees.
 *
 * Inputs:	plat 	- Pointer to first byte.
 *
 * Returns:	Double precision value in degrees.  Negative for South.
 *
 * Description:	Latitude is expressed as a fixed 8-character field, in degrees 
 *		and decimal minutes (to two decimal places), followed by the 
 *		letter N for north or S for south.
 *		The protocol spec specifies upper case but I've seen lower
 *		case so this will accept either one.
 *		Latitude degrees are in the range 00 to 90. Latitude minutes 
 *		are expressed as whole minutes and hundredths of a minute, 
 *		separated by a decimal point.
 *		For example:
 *		4903.50N is 49 degrees 3 minutes 30 seconds north.
 *		In generic format examples, the latitude is shown as the 8-character 
 *		string ddmm.hhN (i.e. degrees, minutes and hundredths of a minute north).
 *
 * Bug:		We don't properly deal with position ambiguity where trailing
 *		digits might be replaced by spaces.  We simply treat them like zeros.	
 *
 * Errors:	Return G_UNKNOWN for any type of error.
 *
 *		Should probably print an error message.
 *
 *------------------------------------------------------------------*/

double get_latitude_8 (char *p, int quiet)
{
	struct lat_s {
	  unsigned char deg[2];
	  unsigned char minn[2];
	  char dot;
	  unsigned char hmin[2];
	  char ns;
	} *plat;

	double result = 0;
	
	plat = (void *)p;

	if (isdigit(plat->deg[0]))
	  result += ((plat->deg[0]) - '0') * 10;
	else {
	  if ( ! quiet) {
	    text_color_set(DW_COLOR_ERROR);
	    dw_printf("Invalid character in latitude.  Found '%c' when expecting 0-9 for tens of degrees.\n", plat->deg[0]);
	  }
	  return (G_UNKNOWN);
	}

	if (isdigit(plat->deg[1]))
	  result += ((plat->deg[1]) - '0') * 1;
	else {
	  if ( ! quiet) {
	    text_color_set(DW_COLOR_ERROR);
	    dw_printf("Invalid character in latitude.  Found '%c' when expecting 0-9 for degrees.\n", plat->deg[1]);
	  }
	  return (G_UNKNOWN);
	}

	if (plat->minn[0] >= '0' && plat->minn[0] <= '5')
	  result += ((plat->minn[0]) - '0') * (10. / 60.);
	else if (plat->minn[0] == ' ')
	  ;
	else {
	  if ( ! quiet) {
	    text_color_set(DW_COLOR_ERROR);
	    dw_printf("Invalid character in latitude.  Found '%c' when expecting 0-5 for tens of minutes.\n", plat->minn[0]);
	  }
	  return (G_UNKNOWN);
	}

	if (isdigit(plat->minn[1]))
	  result += ((plat->minn[1]) - '0') * (1. / 60.);
	else if (plat->minn[1] == ' ')
	  ;
	else {
	  if ( ! quiet) {
	    text_color_set(DW_COLOR_ERROR);
	    dw_printf("Invalid character in latitude.  Found '%c' when expecting 0-9 for minutes.\n", plat->minn[1]);
	  }
	  return (G_UNKNOWN);
	}

	if (plat->dot != '.') {
	  if ( ! quiet) {
	    text_color_set(DW_COLOR_ERROR);
	    dw_printf("Unexpected character \"%c\" found where period expected in latitude.\n", plat->dot);
	  }
	  return (G_UNKNOWN);
	} 

	if (isdigit(plat->hmin[0]))
	  result += ((plat->hmin[0]) - '0') * (0.1 / 60.);
	else if (plat->hmin[0] == ' ')
	  ;
	else {
	  if ( ! quiet) {
	    text_color_set(DW_COLOR_ERROR);
	    dw_printf("Invalid character in latitude.  Found '%c' when expecting 0-9 for tenths of minutes.\n", plat->hmin[0]);
	  }
	  return (G_UNKNOWN);
	}

	if (isdigit(plat->hmin[1]))
	  result += ((plat->hmin[1]) - '0') * (0.01 / 60.);
	else if (plat->hmin[1] == ' ')
	  ;
	else {
	  if ( ! quiet) {
	    text_color_set(DW_COLOR_ERROR);
	    dw_printf("Invalid character in latitude.  Found '%c' when expecting 0-9 for hundredths of minutes.\n", plat->hmin[1]);
	  }
	  return (G_UNKNOWN);
	}

// The spec requires upper case for hemisphere.  Accept lower case but warn.

	if (plat->ns == 'N') {
	  return (result);
        }
        else if (plat->ns == 'n') {
	  if ( ! quiet) {
	    text_color_set(DW_COLOR_ERROR);
	    dw_printf("Warning: Lower case n found for latitude hemisphere.  Specification requires upper case N or S.\n");
	  }	  
	  return (result);
	}
	else if (plat->ns == 'S') {
	  return ( - result);
	}
	else if (plat->ns == 's') {
	  if ( ! quiet) {
	    text_color_set(DW_COLOR_ERROR);
	    dw_printf("Warning: Lower case s found for latitude hemisphere.  Specification requires upper case N or S.\n");	
	  }  
	  return ( - result);
	}
	else {
	  if ( ! quiet) {
	    text_color_set(DW_COLOR_ERROR);
	    dw_printf("Error: '%c' found for latitude hemisphere.  Specification requires upper case N or S.\n", plat->ns);	 
	  } 
	  return (G_UNKNOWN);	
	}	
}


/*------------------------------------------------------------------
 *
 * Function:	get_longitude_9
 *
 * Purpose:	Convert 9 byte longitude encoding to degrees.
 *
 * Inputs:	plat 	- Pointer to first byte.
 *
 * Returns:	Double precision value in degrees.  Negative for West.
 *
 * Description:	Longitude is expressed as a fixed 9-character field, in degrees and 
 *		decimal minutes (to two decimal places), followed by the letter E 
 *		for east or W for west.
 *		Longitude degrees are in the range 000 to 180. Longitude minutes are
 *		expressed as whole minutes and hundredths of a minute, separated by a
 *		decimal point.
 *		For example:
 *		07201.75W is 72 degrees 1 minute 45 seconds west.
 *		In generic format examples, the longitude is shown as the 9-character 
 *		string dddmm.hhW (i.e. degrees, minutes and hundredths of a minute west).
 *
 * Bug:		We don't properly deal with position ambiguity where trailing
 *		digits might be replaced by spaces.  We simply treat them like zeros.	
 *
 * Errors:	Return G_UNKNOWN for any type of error.
 *
 * Example:	
 *
 *------------------------------------------------------------------*/


double get_longitude_9 (char *p, int quiet)
{
	struct lat_s {
	  unsigned char deg[3];
	  unsigned char minn[2];
	  char dot;
	  unsigned char hmin[2];
	  char ew;
	} *plon;

	double result = 0;
	
	plon = (void *)p;

	if (plon->deg[0] == '0' || plon->deg[0] == '1')
	  result += ((plon->deg[0]) - '0') * 100;
	else {
	  if ( ! quiet) {
	    text_color_set(DW_COLOR_ERROR);
	    dw_printf("Invalid character in longitude.  Found '%c' when expecting 0 or 1 for hundreds of degrees.\n", plon->deg[0]);
	  }
	  return (G_UNKNOWN);
	}

	if (isdigit(plon->deg[1]))
	  result += ((plon->deg[1]) - '0') * 10;
	else {
	  if ( ! quiet) {
	    text_color_set(DW_COLOR_ERROR);
	    dw_printf("Invalid character in longitude.  Found '%c' when expecting 0-9 for tens of degrees.\n", plon->deg[1]);
	  }
	  return (G_UNKNOWN);
	}

	if (isdigit(plon->deg[2]))
	  result += ((plon->deg[2]) - '0') * 1;
	else {
	  if ( ! quiet) {
	    text_color_set(DW_COLOR_ERROR);
	    dw_printf("Invalid character in longitude.  Found '%c' when expecting 0-9 for degrees.\n", plon->deg[2]);
	  }
	  return (G_UNKNOWN);
	}

	if (plon->minn[0] >= '0' && plon->minn[0] <= '5')
	  result += ((plon->minn[0]) - '0') * (10. / 60.);
	else if (plon->minn[0] == ' ')
	  ;
	else {
	  if ( ! quiet) {
	    text_color_set(DW_COLOR_ERROR);
	    dw_printf("Invalid character in longitude.  Found '%c' when expecting 0-5 for tens of minutes.\n", plon->minn[0]);
	  }
	  return (G_UNKNOWN);
	}

	if (isdigit(plon->minn[1]))
	  result += ((plon->minn[1]) - '0') * (1. / 60.);
	else if (plon->minn[1] == ' ')
	  ;
	else {
	  if ( ! quiet) {
	    text_color_set(DW_COLOR_ERROR);
	    dw_printf("Invalid character in longitude.  Found '%c' when expecting 0-9 for minutes.\n", plon->minn[1]);
	  }
	  return (G_UNKNOWN);
	}

	if (plon->dot != '.') {
	  if ( ! quiet) {
	    text_color_set(DW_COLOR_ERROR);
	    dw_printf("Unexpected character \"%c\" found where period expected in longitude.\n", plon->dot);
	  }
	  return (G_UNKNOWN);
	} 

	if (isdigit(plon->hmin[0]))
	  result += ((plon->hmin[0]) - '0') * (0.1 / 60.);
	else if (plon->hmin[0] == ' ')
	  ;
	else {
	  if ( ! quiet) {
	    text_color_set(DW_COLOR_ERROR);
	    dw_printf("Invalid character in longitude.  Found '%c' when expecting 0-9 for tenths of minutes.\n", plon->hmin[0]);
	  }
	  return (G_UNKNOWN);
	}

	if (isdigit(plon->hmin[1]))
	  result += ((plon->hmin[1]) - '0') * (0.01 / 60.);
	else if (plon->hmin[1] == ' ')
	  ;
	else {
	  if ( ! quiet) {
	    text_color_set(DW_COLOR_ERROR);
	    dw_printf("Invalid character in longitude.  Found '%c' when expecting 0-9 for hundredths of minutes.\n", plon->hmin[1]);
	  }
	  return (G_UNKNOWN);
	}

// The spec requires upper case for hemisphere.  Accept lower case but warn.

	if (plon->ew == 'E') {
	  return (result);
        }
        else if (plon->ew == 'e') {
	  if ( ! quiet) {
	    text_color_set(DW_COLOR_ERROR);
	    dw_printf("Warning: Lower case e found for longitude hemisphere.  Specification requires upper case E or W.\n");
	  }	  
	  return (result);
	}
	else if (plon->ew == 'W') {
	  return ( - result);
	}
	else if (plon->ew == 'w') {
	  if ( ! quiet) {
	    text_color_set(DW_COLOR_ERROR);
	    dw_printf("Warning: Lower case w found for longitude hemisphere.  Specification requires upper case E or W.\n");
	  }	  
	  return ( - result);
	}
	else {
	  if ( ! quiet) {
	    text_color_set(DW_COLOR_ERROR);
	    dw_printf("Error: '%c' found for longitude hemisphere.  Specification requires upper case E or W.\n", plon->ew);	
	  }  
	  return (G_UNKNOWN);	
	}		
}


/*------------------------------------------------------------------
 *
 * Function:	get_timestamp
 *
 * Purpose:	Convert 7 byte timestamp to unix time value.
 *
 * Inputs:	p 	- Pointer to first byte.
 *
 * Returns:	time_t data type. (UTC)
 *
 * Description:	
 *
 *		Day/Hours/Minutes (DHM) format is a fixed 7-character field, consisting of
 *		a 6-digit day/time group followed by a single time indicator character (z or
 *		/). The day/time group consists of a two-digit day-of-the-month (01-31) and
 *		a four-digit time in hours and minutes.
 *		Times can be expressed in zulu (UTC/GMT) or local time. For example:
 *
 *		  092345z is 2345 hours zulu time on the 9th day of the month.
 *		  092345/ is 2345 hours local time on the 9th day of the month.
 *
 *		It is recommended that future APRS implementations only transmit zulu
 *		format on the air.
 *
 *		Note: The time in Status Reports may only be in zulu format.
 *
 *		Hours/Minutes/Seconds (HMS) format is a fixed 7-character field,
 *		consisting of a 6-digit time in hours, minutes and seconds, followed by the h
 *		time-indicator character. For example:
 *
 *		  234517h is 23 hours 45 minutes and 17 seconds zulu.
 *
 *		Note: This format may not be used in Status Reports.
 *
 *		Month/Day/Hours/Minutes (MDHM) format is a fixed 8-character field,
 *		consisting of the month (01-12) and day-of-the-month (01-31), followed by
 *		the time in hours and minutes zulu. For example:
 *
 *		  10092345 is 23 hours 45 minutes zulu on October 9th.
 *
 *		This format is only used in reports from stand-alone "positionless" weather
 *		stations (i.e. reports that do not contain station position information).
 *
 *
 * Bugs:	Local time not implemented yet.
 *		8 character form not implemented yet.
 *
 *		Boundary conditions are not handled properly.
 *		For example, suppose it is 00:00:03 on January 1.
 *		We receive a timestamp of 23:59:58 (which was December 31).
 *		If we simply replace the time, and leave the current date alone,
 *		the result is about a day into the future.
 *
 *
 * Example:	
 *
 *------------------------------------------------------------------*/


time_t get_timestamp (decode_aprs_t *A, char *p)
{
	struct dhm_s {
	  char day[2];
	  char hours[2];
	  char minutes[2];
	  char tic;		/* Time indicator character. */
				/* z = UTC. */
				/* / = local - not implemented yet. */
	} *pdhm;

	struct hms_s {
	  char hours[2];
	  char minutes[2];
	  char seconds[2];
	  char tic;		/* Time indicator character. */
				/* h = UTC. */
	} *phms;

	struct tm *ptm;

	time_t ts;

	ts = time(NULL);
	// FIXME: use gmtime_r instead.
	// Besides not being thread safe, gmtime could possibly return null.
	ptm = gmtime(&ts);

	pdhm = (void *)p;
	phms = (void *)p;

	if (pdhm->tic == 'z' || pdhm->tic == '/')   /* Wrong! */
	{
	  int j;

	  j = (pdhm->day[0] - '0') * 10 + pdhm->day[1] - '0';
	  //text_color_set(DW_COLOR_DECODED);
	  //dw_printf("Changing day from %d to %d\n", ptm->tm_mday, j);
	  ptm->tm_mday = j;

	  j = (pdhm->hours[0] - '0') * 10 + pdhm->hours[1] - '0';
	  //dw_printf("Changing hours from %d to %d\n", ptm->tm_hour, j);
	  ptm->tm_hour = j;

	  j = (pdhm->minutes[0] - '0') * 10 + pdhm->minutes[1] - '0';
	  //dw_printf("Changing minutes from %d to %d\n", ptm->tm_min, j);
	  ptm->tm_min = j;

	} 
	else if (phms->tic == 'h') 
	{
	  int j;

	  j = (phms->hours[0] - '0') * 10 + phms->hours[1] - '0';
	  //text_color_set(DW_COLOR_DECODED);
	  //dw_printf("Changing hours from %d to %d\n", ptm->tm_hour, j);
	  ptm->tm_hour = j;

	  j = (phms->minutes[0] - '0') * 10 + phms->minutes[1] - '0';
	  //dw_printf("Changing minutes from %d to %d\n", ptm->tm_min, j);
	  ptm->tm_min = j;

	  j = (phms->seconds[0] - '0') * 10 + phms->seconds[1] - '0';
	  //dw_printf("%sChanging seconds from %d to %d\n", ptm->tm_sec, j);
	  ptm->tm_sec = j;
	} 
	
	return (mktime(ptm));
}




/*------------------------------------------------------------------
 *
 * Function:	get_maidenhead
 *
 * Purpose:	See if we have a maidenhead locator.
 *
 * Inputs:	p 	- Pointer to first byte.
 *
 * Returns:	0 = not found.
 *		4 = possible 4 character locator found.
 *		6 = possible 6 character locator found.
 *
 *		It is not stored anywhere or processed.
 *
 * Description:	
 *
 *		The maidenhead locator system is sometimes used as a more compact, 
 *		and less precise, alternative to numeric latitude and longitude.
 *
 *		It is composed of:
 *			a pair of letters in range A to R.
 *			a pair of digits in range of 0 to 9.
 *			an optional pair of letters in range of A to X.
 *
 *		The spec says:
 *				"All letters must be transmitted in upper case.
 *				Letters may be received in upper case or lower case."
 *
 *		Typically the second set of letters is written in lower case.
 *		An earlier version incorrectly produced an error if lower case found.
 *
 *
 * Examples from APRS spec:	
 *
 *		IO91SX
 *		IO91
 *
 *
 *------------------------------------------------------------------*/


int get_maidenhead (decode_aprs_t *A, char *p)
{

	if (toupper(p[0]) >= 'A' && toupper(p[0]) <= 'R' &&
	    toupper(p[1]) >= 'A' && toupper(p[1]) <= 'R' &&
	    isdigit(p[2]) && isdigit(p[3])) {

	  /* We have 4 characters matching the rule. */

	  if (toupper(p[4]) >= 'A' && toupper(p[4]) <= 'X' &&
	      toupper(p[5]) >= 'A' && toupper(p[5]) <= 'X') {

	    /* We have 6 characters matching the rule. */
	    return 6;
	  }
	
	  return 4;
	}

	return 0;
}



/*------------------------------------------------------------------
 *
 * Function:	data_extension_comment
 *
 * Purpose:	A fixed length 7-byte field may follow APRS position datA->
 *
 * Inputs:	pdext	- Pointer to optional data extension and comment.
 *
 * Returns:	true if a data extension was found.
 *
 * Outputs:	One or more of the following, depending the data found:
 *	
 *			A->g_course
 *			A->g_speed_mph
 *			A->g_power 
 *			A->g_height 
 *			A->g_gain 
 *			A->g_directivity 
 *			A->g_range
 *
 *		Anything left over will be put in 
 *
 *			A->g_comment			
 *
 * Description:	
 *
 *
 *
 *------------------------------------------------------------------*/

const char *dir[9] = { "omni", "NE", "E", "SE", "S", "SW", "W", "NW", "N" };

static int data_extension_comment (decode_aprs_t *A, char *pdext)
{
	int n;

	if (strlen(pdext) < 7) {
	  strlcpy (A->g_comment, pdext, sizeof(A->g_comment));
	  return 0;
	}

/* Tyy/Cxx - Area object descriptor. */

	if (pdext[0] == 'T' &&
		pdext[3] == '/' &&
	 	pdext[4] == 'C')
	{
	  /* not decoded at this time */
	  process_comment (A, pdext+7, -1);
	  return 1;
	}

/* CSE/SPD */
/* For a weather station (symbol code _) this is wind. */
/* For others, it would be course and speed. */

	if (pdext[3] == '/')
	{
	  if (sscanf (pdext, "%3d", &n))
	  {
	    A->g_course = n;
	  }
	  if (sscanf (pdext+4, "%3d", &n))
	  {
	    A->g_speed_mph = DW_KNOTS_TO_MPH(n);
	  }

	  /* Bearing and Number/Range/Quality? */

	  if (pdext[7] == '/' && pdext[11] == '/') 
	  {
	    process_comment (A, pdext + 7 + 8, -1);
	  }
	  else {
	    process_comment (A, pdext+7, -1);
	  }
	  return 1;
	}

/* check for Station power, height, gain. */

	if (strncmp(pdext, "PHG", 3) == 0)
	{
	  A->g_power = (pdext[3] - '0') * (pdext[3] - '0');
	  A->g_height = (1 << (pdext[4] - '0')) * 10;
	  A->g_gain = pdext[5] - '0';
	  if (pdext[6] >= '0' && pdext[6] <= '8') {
	    strlcpy (A->g_directivity, dir[pdext[6]-'0'], sizeof(A->g_directivity));
	  }

// TODO: look for another 0-9 A-Z followed by a /
// http://www.aprs.org/aprs12/probes.txt

	  process_comment (A, pdext+7, -1);
	  return 1;
	}

/* check for precalculated radio range. */

	if (strncmp(pdext, "RNG", 3) == 0)
	{
	  if (sscanf (pdext+3, "%4d", &n))
	  {
	    A->g_range = n;
	  }
	  process_comment (A, pdext+7, -1);
	  return 1;
	}

/* DF signal strength,  */

	if (strncmp(pdext, "DFS", 3) == 0)
	{
	  //A->g_strength = pdext[3] - '0';
	  A->g_height = (1 << (pdext[4] - '0')) * 10;
	  A->g_gain = pdext[5] - '0';
	  if (pdext[6] >= '0' && pdext[6] <= '8') {
	    strlcpy (A->g_directivity, dir[pdext[6]-'0'], sizeof(A->g_directivity));
	  }

	  process_comment (A, pdext+7, -1);
	  return 1;
	}

	process_comment (A, pdext, -1);
	return 0;
}


/*------------------------------------------------------------------
 *
 * Function:	decode_tocall
 *
 * Purpose:	Extract application from the destination.
 *
 * Inputs:	dest	- Destination address.
 *			Don't care if SSID is present or not.
 *
 * Outputs:	A->g_mfr
 *
 * Description:	For maximum flexibility, we will read the
 *		data file at run time rather than compiling it in.
 *
 *		For the most recent version, download from:
 *
 *		http://www.aprs.org/aprs11/tocalls.txt
 *
 *		Windows version:  File must be in current working directory.
 *
 *		Linux version: Search order is current working directory then
 *			/usr/local/share/direwolf
 *			/usr/share/direwolf/tocalls.txt
 *
 *		Mac: Like Linux and then
 *			/opt/local/share/direwolf
 *
 *------------------------------------------------------------------*/

// If I was more ambitious, this would dynamically allocate enough
// storage based on the file contents.  Just stick in a constant for
// now.  This takes an insignificant amount of space and
// I don't anticipate tocalls.txt growing that quickly.
// Version 1.4 - add message if too small instead of silently ignoring the rest.

// Dec. 2016 tocalls.txt has 153 destination addresses.

#define MAX_TOCALLS 250

static struct tocalls_s {
	unsigned char len;
	char prefix[7];
	char *description;
} tocalls[MAX_TOCALLS];

static int num_tocalls = 0;

// Make sure the array is null terminated.
// If search order is changed, do the same in symbols.c for consistency.

static const char *search_locations[] = {
	(const char *) "tocalls.txt",			// CWD
	(const char *) "data/tocalls.txt",		// Windows with CMake
	(const char *) "../data/tocalls.txt",		// ?
#ifndef __WIN32__
	(const char *) "/usr/local/share/direwolf/tocalls.txt",
	(const char *) "/usr/share/direwolf/tocalls.txt",
#endif
#if __APPLE__
	// https://groups.yahoo.com/neo/groups/direwolf_packet/conversations/messages/2458
	// Adding the /opt/local tree since macports typically installs there.  Users might want their
	// INSTALLDIR (see Makefile.macosx) to mirror that.  If so, then we need to search the /opt/local
	// path as well.
	(const char *) "/opt/local/share/direwolf/tocalls.txt",
#endif
	(const char *) NULL		// Important - Indicates end of list.
};

static int tocall_cmp (const void *px, const void *py)
{
	const struct tocalls_s *x = (struct tocalls_s *)px;
	const struct tocalls_s *y = (struct tocalls_s *)py;

	if (x->len != y->len) return (y->len - x->len);
	return (strcmp(x->prefix, y->prefix));
}

static void decode_tocall (decode_aprs_t *A, char *dest)
{
	FILE *fp = 0;
	int n = 0;
	static int first_time = 1;
	char stuff[100];
	char *p = NULL;
	char *r = NULL;

	//dw_printf("debug: decode_tocall(\"%s\")\n", dest);

/*
 * Extract the calls and descriptions from the file.
 *
 * Use only lines with exactly these formats:
 *
 *       APN          Network nodes, digis, etc
 *	      APWWxx  APRSISCE win32 version
 *	|     |       |
 *	00000000001111111111      	
 *	01234567890123456789...
 *
 * Matching will be with only leading upper case and digits.
 */

// TODO:  Look for this in multiple locations.
// For example, if application was installed in /usr/local/bin,
// we might want to put this in /usr/local/share/aprs

// If search strategy changes, be sure to keep symbols_init in sync.

	if (first_time) {

	  n = 0;
	  fp = NULL;
	  do {
	    if(search_locations[n] == NULL) break;
	    fp = fopen(search_locations[n++], "r");
	  } while (fp == NULL);

	  if (fp != NULL) {

	    while (fgets(stuff, sizeof(stuff), fp) != NULL && num_tocalls < MAX_TOCALLS) {
	      
	      p = stuff + strlen(stuff) - 1;
	      while (p >= stuff && (*p == '\r' || *p == '\n')) {
	        *p-- = '\0';
	      }

	      // dw_printf("debug: %s\n", stuff);

	      if (stuff[0] == ' ' && 
		  stuff[4] == ' ' &&
		  stuff[5] == ' ' &&
		  stuff[6] == 'A' && 
		  stuff[7] == 'P' && 
		  stuff[12] == ' ' &&
		  stuff[13] == ' ' ) {

	        p = stuff + 6;
	        r = tocalls[num_tocalls].prefix;
	        while (isupper((int)(*p)) || isdigit((int)(*p))) {
	          *r++ = *p++;
	        }
	        *r = '\0';
	        if (strlen(tocalls[num_tocalls].prefix) > 2) {
	          tocalls[num_tocalls].description = strdup(stuff+14);
		  tocalls[num_tocalls].len = strlen(tocalls[num_tocalls].prefix);
	          // dw_printf("debug %d: %d '%s' -> '%s'\n", num_tocalls, tocalls[num_tocalls].len, tocalls[num_tocalls].prefix, tocalls[num_tocalls].description);

	          num_tocalls++;
	        }
	      }
	      else if (stuff[0] == ' ' && 
		  stuff[1] == 'A' && 
		  stuff[2] == 'P' && 
		  isupper((int)(stuff[3])) &&
		  stuff[4] == ' ' &&
		  stuff[5] == ' ' &&
		  stuff[6] == ' ' &&
		  stuff[12] == ' ' &&
		  stuff[13] == ' ' ) {

	        p = stuff + 1;
	        r = tocalls[num_tocalls].prefix;
	        while (isupper((int)(*p)) || isdigit((int)(*p))) {
	          *r++ = *p++;
	        }
	        *r = '\0';
	        if (strlen(tocalls[num_tocalls].prefix) > 2) {
	          tocalls[num_tocalls].description = strdup(stuff+14);
		  tocalls[num_tocalls].len = strlen(tocalls[num_tocalls].prefix);
	          // dw_printf("debug %d: %d '%s' -> '%s'\n", num_tocalls, tocalls[num_tocalls].len, tocalls[num_tocalls].prefix, tocalls[num_tocalls].description);

	          num_tocalls++;
	        }
	      }
	      if (num_tocalls == MAX_TOCALLS) {		// oops. might have discarded some.
	        text_color_set(DW_COLOR_ERROR);
	        dw_printf("MAX_TOCALLS needs to be larger than %d to handle contents of 'tocalls.txt'.\n", MAX_TOCALLS);
	      }
	    }
	    fclose(fp);

/*
 * Sort by decreasing length so the search will go
 * from most specific to least specific.
 * Example:  APY350 or APY008 would match those specific
 * models before getting to the more generic APY.
 */

	    qsort (tocalls, num_tocalls, sizeof(struct tocalls_s), tocall_cmp);

	  }
	  else {
	    if ( ! A->g_quiet) {
	      text_color_set(DW_COLOR_ERROR);
	      dw_printf("Warning: Could not open 'tocalls.txt'.\n");
	      dw_printf("System types in the destination field will not be decoded.\n");
	    }
	  }
	
	  first_time = 0;

	  //for (n=0; n<num_tocalls; n++) {
	  //  dw_printf("sorted %d: %d '%s' -> '%s'\n", n, tocalls[n].len, tocalls[n].prefix, tocalls[n].description);
	  //}
	}


	for (n=0; n<num_tocalls; n++) {
	  if (strncmp(dest, tocalls[n].prefix, tocalls[n].len) == 0) {
	    strlcpy (A->g_mfr, tocalls[n].description, sizeof(A->g_mfr));
	    return;
	  }
	}

} /* end decode_tocall */ 



/*------------------------------------------------------------------
 *
 * Function:	substr_se
 *
 * Purpose:	Extract substring given start and end+1 offset.
 *
 * Inputs:	src		- Source string
 *
 *		start		- Start offset.
 *		
 *		endp1		- End offset+1 for ease of use with regexec result.
 *
 * Outputs:	dest		- Destination for substring.
 *
 *------------------------------------------------------------------*/

// TODO: potential for buffer overflow here.

static void substr_se (char *dest, const char *src, int start, int endp1)
{
	int len = endp1 - start;

	if (start < 0 || endp1 < 0 || len <= 0) {
	  dest[0] = '\0';
	  return;
	}
	memcpy (dest, src + start, len);
	dest[len] = '\0';

} /* end substr_se */
	


/*------------------------------------------------------------------
 *
 * Function:	process_comment
 *
 * Purpose:	Extract optional items from the comment.
 *
 * Inputs:	pstart		- Pointer to start of left over information field.
 *
 *		clen		- Length of comment or -1 to take it all.
 *
 * Outputs:	A->g_telemetry	- Base 91 telemetry |ss1122|
 *		A->g_altitude_ft - from /A=123456
 *		A->g_lat	- Might be adjusted from !DAO!
 *		A->g_lon	- Might be adjusted from !DAO!
 *		A->g_aprstt_loc	- Private extension to !DAO!
 *		A->g_freq
 *		A->g_tone
 *		A->g_offset
 *		A->g_comment	- Anything left over after extracting above.
 *
 * Description:	After processing fixed and possible optional parts
 *		of the message, everything left over is a comment.
 *
 *		Except!!!
 *
 *		There are could be some other pieces of data, with 
 *		particular formats, buried in there.
 *		Pull out those special items and put everything 
 *		else into A->g_comment.
 *
 * References:	http://www.aprs.org/info/freqspec.txt
 *
 *			999.999MHz T100 +060	Voice frequency.
 *		
 *		http://www.aprs.org/datum.txt
 *
 *			!DAO!			APRS precision and Datum option.
 *
 *		Protocol reference, end of chapter 6.
 *
 *			/A=123456		Altitude
 *
 * What can appear in a comment?
 *
 *		Chapter 5 of the APRS spec ( http://www.aprs.org/doc/APRS101.PDF ) says:
 *
 *			"The comment may contain any printable ASCII characters (except | and ~,
 *			which are reserved for TNC channel switching)."
 *
 *		"Printable" would exclude character values less than space (00100000), e.g.
 *		tab, carriage return, line feed, nul.  Sometimes we see carriage return
 *		(00001010) at the end of APRS packets.   This would be in violation of the
 *		specification.
 *
 *		The base 91 telemetry format (http://he.fi/doc/aprs-base91-comment-telemetry.txt ),
 *		which is not part of the APRS spec, uses the | character in the comment to delimit encoded
 *		telemetry data.   This would be in violation of the original spec.
 *
 *		The APRS Spec Addendum 1.2 Proposals ( http://www.aprs.org/aprs12/datum.txt)
 *		adds use of UTF-8 (https://en.wikipedia.org/wiki/UTF-8 )for the free form text in
 *		messages and comments. It can't be used in the fixed width fields.
 *
 *		Non-ASCII characters are represented by multi-byte sequences.  All bytes in these
 *		multi-byte sequences have the most significant bit set to 1.  Using UTF-8 would not
 *		add any nul (00000000) bytes to the stream.
 *
 *		There are two known cases where we can have a nul character value.
 *
 *		* The Kenwood TM-D710A sometimes sends packets like this:
 *
 *			VA3AJ-9>T2QU6X,VE3WRC,WIDE1,K8UNS,WIDE2*:4P<0x00><0x0f>4T<0x00><0x0f>4X<0x00><0x0f>4\<0x00>`nW<0x1f>oS8>/]"6M}driving fast= 
 *			K4JH-9>S5UQ6X,WR4AGC-3*,WIDE1*:4P<0x00><0x0f>4T<0x00><0x0f>4X<0x00><0x0f>4\<0x00>`jP}l"&>/]"47}QRV from the EV =
 *
 *		  Notice that the data type indicator of "4" is not valid.  If we remove
 *		  4P<0x00><0x0f>4T<0x00><0x0f>4X<0x00><0x0f>4\<0x00>   we are left with a good MIC-E format.
 *		  This same thing has been observed from others and is intermittent.
 *
 *		* AGW Tracker can send UTF-16 if an option is selected.  This can introduce nul bytes.
 *		  This is wrong.  It should be using UTF-8 and I'm not going to accommodate it here.
 *
 *
 *		The digipeater and IGate functions should pass along anything exactly the
 *		we received it, even if it is invalid.  If different implementations try to fix it up
 *		somehow, like changing unprintable characters to spaces, we will only make things
 *		worse and thwart the duplicate detection.
 *
 *------------------------------------------------------------------*/

/* CTCSS tones in various formats to avoid conversions every time. */

#define NUM_CTCSS 50

static const int i_ctcss[NUM_CTCSS] = {
         67,  69,  71,  74,  77,  79,  82,  85,  88,  91,
         94,  97, 100, 103, 107, 110, 114, 118, 123, 127,
        131, 136, 141, 146, 151, 156, 159, 162, 165, 167,
        171, 173, 177, 179, 183, 186, 189, 192, 196, 199,
        203, 206, 210, 218, 225, 229, 233, 241, 250, 254 };

static const float f_ctcss[NUM_CTCSS] = {
         67.0,  69.3,  71.9,  74.4,  77.0,  79.7,  82.5,  85.4,  88.5,  91.5,
         94.8,  97.4, 100.0, 103.5, 107.2, 110.9, 114.8, 118.8, 123.0, 127.3,
        131.8, 136.5, 141.3, 146.2, 151.4, 156.7, 159.8, 162.2, 165.5, 167.9,
        171.3, 173.8, 177.3, 179.9, 183.5, 186.2, 189.9, 192.8, 196.6, 199.5,
        203.5, 206.5, 210.7, 218.1, 225.7, 229.1, 233.6, 241.8, 250.3, 254.1 };

static const char * s_ctcss[NUM_CTCSS] = {
         "67.0",  "69.3",  "71.9",  "74.4",  "77.0",  "79.7",  "82.5",  "85.4",  "88.5",  "91.5",
         "94.8",  "97.4", "100.0", "103.5", "107.2", "110.9", "114.8", "118.8", "123.0", "127.3",
        "131.8", "136.5", "141.3", "146.2", "151.4", "156.7", "159.8", "162.2", "165.5", "167.9",
        "171.3", "173.8", "177.3", "179.9", "183.5", "186.2", "189.9", "192.8", "196.6", "199.5",
        "203.5", "206.5", "210.7", "218.1", "225.7", "229.1", "233.6", "241.8", "250.3", "254.1" };


#define sign(x) (((x)>=0)?1:(-1))

static void process_comment (decode_aprs_t *A, char *pstart, int clen)
{
	static int first_time = 1;
	static regex_t std_freq_re;	/* Frequency in standard format. */
	static regex_t std_tone_re;	/* Tone in standard format. */
	static regex_t std_toff_re;	/* Explicitly no tone. */
	static regex_t std_dcs_re;	/* Digital codes squelch in standard format. */
	static regex_t std_offset_re;	/* Xmit freq offset in standard format. */
	static regex_t std_range_re;	/* Range in standard format. */

	static regex_t dao_re;		/* DAO */
	static regex_t alt_re;		/* /A= altitude */

	static regex_t bad_freq_re;	/* Likely frequency, not standard format */
	static regex_t bad_tone_re;	/* Likely tone, not standard format */

	static regex_t base91_tel_re;	/* Base 91 compressed telemetry data. */


	int e;
	char emsg[100];
#define MAXMATCH 4
	regmatch_t match[MAXMATCH];
	char temp[sizeof(A->g_comment)];
	int keep_going;


/*
 * No sense in recompiling the patterns and freeing every time.
 */	
	if (first_time) 
	{
/*
 * Frequency must be at the at the beginning.
 * Others can be anywhere in the comment.
 */
		
	  //e = regcomp (&freq_re, "^[0-9A-O][0-9][0-9]\\.[0-9][0-9][0-9 ]MHz( [TCDtcd][0-9][0-9][0-9]| Toff)?( [+-][0-9][0-9][0-9])?", REG_EXTENDED);

	  // Freq optionally preceded by space or /.
	  // Third fractional digit can be space instead.
	  // "MHz" should be exactly that capitalization.  
	  // Print warning later it not.

	  e = regcomp (&std_freq_re, "^[/ ]?([0-9A-O][0-9][0-9]\\.[0-9][0-9][0-9 ])([Mm][Hh][Zz])", REG_EXTENDED);
	  if (e) {
	    regerror (e, &std_freq_re, emsg, sizeof(emsg));
	    dw_printf("%s:%d: %s\n", __FILE__, __LINE__, emsg);
	  }

	  // If no tone, we might gobble up / after any data extension,
	  // We could also have a space but it's not required.
	  // I don't understand the difference between T and C so treat the same for now.
	  // We can also have "off" instead of number to explicitly mean none.

	  e = regcomp (&std_tone_re, "^[/ ]?([TtCc][012][0-9][0-9])", REG_EXTENDED);
	  if (e) {
	    regerror (e, &std_tone_re, emsg, sizeof(emsg));
	    dw_printf("%s:%d: %s\n", __FILE__, __LINE__, emsg);
	  }

	  e = regcomp (&std_toff_re, "^[/ ]?[TtCc][Oo][Ff][Ff]", REG_EXTENDED);
	  if (e) {
	    regerror (e, &std_toff_re, emsg, sizeof(emsg));
	    dw_printf("%s:%d: %s\n", __FILE__, __LINE__, emsg);
	  }

	  e = regcomp (&std_dcs_re, "^[/ ]?[Dd]([0-7][0-7][0-7])", REG_EXTENDED);
	  if (e) {
	    regerror (e, &std_dcs_re, emsg, sizeof(emsg));
	    dw_printf("%s:%d: %s\n", __FILE__, __LINE__, emsg);
	  }
	  e = regcomp (&std_offset_re, "^[/ ]?([+-][0-9][0-9][0-9])", REG_EXTENDED);
	  if (e) {
	    regerror (e, &std_offset_re, emsg, sizeof(emsg));
	    dw_printf("%s:%d: %s\n", __FILE__, __LINE__, emsg);
	  }

	  e = regcomp (&std_range_re, "^[/ ]?[Rr]([0-9][0-9])([mk])", REG_EXTENDED);
	  if (e) {
	    regerror (e, &std_range_re, emsg, sizeof(emsg));
	    dw_printf("%s:%d: %s\n", __FILE__, __LINE__, emsg);
	  }

	  e = regcomp (&dao_re, "!([A-Z][0-9 ][0-9 ]|[a-z][!-{ ][!-{ ]|T[0-9 B][0-9 ])!", REG_EXTENDED);
	  if (e) {
	    regerror (e, &dao_re, emsg, sizeof(emsg));
	    dw_printf("%s:%d: %s\n", __FILE__, __LINE__, emsg);
	  }

	  e = regcomp (&alt_re, "/A=[0-9][0-9][0-9][0-9][0-9][0-9]", REG_EXTENDED);
	  if (e) {
	    regerror (e, &alt_re, emsg, sizeof(emsg));
	    dw_printf("%s:%d: %s\n", __FILE__, __LINE__, emsg);
	  }

	  e = regcomp (&bad_freq_re, "[0-9][0-9][0-9]\\.[0-9][0-9][0-9]?", REG_EXTENDED);
	  if (e) {
	    regerror (e, &bad_freq_re, emsg, sizeof(emsg));
	    dw_printf("%s:%d: %s\n", __FILE__, __LINE__, emsg);
	  }

	  e = regcomp (&bad_tone_re, "(^|[^0-9.])([6789][0-9]\\.[0-9]|[12][0-9][0-9]\\.[0-9]|67|77|100|123)($|[^0-9.])", REG_EXTENDED);
	  if (e) {
	    regerror (e, &bad_tone_re, emsg, sizeof(emsg));
	    dw_printf("%s:%d: %s\n", __FILE__, __LINE__, emsg);
	  }

	  e = regcomp (&base91_tel_re, "\\|(([!-{][!-{]){2,7})\\|", REG_EXTENDED);
	  if (e) {
	    regerror (e, &base91_tel_re, emsg, sizeof(emsg));
	    dw_printf("%s:%d: %s\n", __FILE__, __LINE__, emsg);
	  }

	  first_time = 0;
	}

/*
 * If clen is >= 0, take only specified number of characters.
 * Otherwise, take it all.
 */
	if (clen < 0) {
	  clen = strlen(pstart);
	}

/*
 * Watch out for buffer overflow.
 * KG6AZZ reports that there is a local digipeater that seems to 
 * malfunction occasionally.  It corrupts the packet, as it is
 * digipeated, causing the comment to be hundreds of characters long.
 */

	if (clen > (int)(sizeof(A->g_comment) - 1)) {
	  if ( ! A->g_quiet) {
	    text_color_set(DW_COLOR_ERROR);
	    dw_printf("Comment is extremely long, %d characters.\n", clen);
	    dw_printf("Please report this, along with surrounding lines, so we can find the cause.\n");
	  }
	  clen = sizeof(A->g_comment) - 1;
	}

	if (clen > 0) {
	  memcpy (A->g_comment, pstart, (size_t)clen);
	  A->g_comment[clen] = '\0';
	}
	else {
	  A->g_comment[0] = '\0';
	}


/*
 * Look for frequency in the standard format at start of comment.
 * If that fails, try to obtain from object name.
 */

	if (regexec (&std_freq_re, A->g_comment, MAXMATCH, match, 0) == 0) 
	{
	  char sftemp[30];
	  char smtemp[10];

          //dw_printf("matches= %d - %d, %d - %d, %d - %d\n", (int)(match[0].rm_so), (int)(match[0].rm_eo), 
	  //						    (int)(match[1].rm_so), (int)(match[1].rm_eo),
	  //						    (int)(match[2].rm_so), (int)(match[2].rm_eo) );

	  substr_se (sftemp, A->g_comment, match[1].rm_so, match[1].rm_eo);
	  substr_se (smtemp, A->g_comment, match[2].rm_so, match[2].rm_eo);
	
	  switch (sftemp[0]) {
	    case 'A': A->g_freq =  1200 + atof(sftemp+1); break;
	    case 'B': A->g_freq =  2300 + atof(sftemp+1); break;
	    case 'C': A->g_freq =  2400 + atof(sftemp+1); break;
	    case 'D': A->g_freq =  3400 + atof(sftemp+1); break;
	    case 'E': A->g_freq =  5600 + atof(sftemp+1); break;
	    case 'F': A->g_freq =  5700 + atof(sftemp+1); break;
	    case 'G': A->g_freq =  5800 + atof(sftemp+1); break;
	    case 'H': A->g_freq = 10100 + atof(sftemp+1); break;
	    case 'I': A->g_freq = 10200 + atof(sftemp+1); break;
	    case 'J': A->g_freq = 10300 + atof(sftemp+1); break;
	    case 'K': A->g_freq = 10400 + atof(sftemp+1); break;
	    case 'L': A->g_freq = 10500 + atof(sftemp+1); break;
	    case 'M': A->g_freq = 24000 + atof(sftemp+1); break;
	    case 'N': A->g_freq = 24100 + atof(sftemp+1); break;
	    case 'O': A->g_freq = 24200 + atof(sftemp+1); break;
	    default:  A->g_freq =         atof(sftemp);   break;
	  }

	  if (strncmp(smtemp, "MHz", 3) != 0) {
	    if ( ! A->g_quiet) {
	      text_color_set(DW_COLOR_ERROR);
	      dw_printf("Warning: \"%s\" has non-standard capitalization and might not be recognized by some systems.\n", smtemp);
	      dw_printf("For best compatibility, it should be exactly like this: \"MHz\"  (upper,upper,lower case)\n");
	    }
	  }

	  strlcpy (temp, A->g_comment + match[0].rm_eo, sizeof(temp));
	  strlcpy (A->g_comment + match[0].rm_so, temp, sizeof(A->g_comment));
	}
	else if (strlen(A->g_name) > 0) {

	  // Try to extract sensible number from object/item name.

	  double x = atof (A->g_name);

	  if ((x >= 144 && x <= 148) ||
	      (x >= 222 && x <= 225) ||
	      (x >= 420 && x <= 450) ||
	      (x >= 902 && x <= 928)) { 
	    A->g_freq = x;
	  }
	}

/*
 * Next, look for tone, DCS code, and range.
 * Examples always have them in same order but it's not clear
 * whether any order is allowed after possible frequency.
 *
 * TODO: Convert integer tone to original value for display.
 * TODO: samples in zfreq-test3.txt
 */

	keep_going = 1;
	while (keep_going) {

	  if (regexec (&std_tone_re, A->g_comment, MAXMATCH, match, 0) == 0) {

	    char sttemp[10];	/* includes leading letter */
	    int f;
	    int i;

	    substr_se (sttemp, A->g_comment, match[1].rm_so, match[1].rm_eo);

	    // Try to convert from integer to proper value.

	    f = atoi(sttemp+1);
	    for (i = 0; i < NUM_CTCSS; i++) {
	      if (f == i_ctcss[i]) {
	        A->g_tone = f_ctcss[i];
	        break;
	      }
	    }
	    if (A->g_tone == G_UNKNOWN) {
	      if ( ! A->g_quiet) {
	        text_color_set(DW_COLOR_ERROR);
	        dw_printf("Bad CTCSS/PL specification: \"%s\"\n", sttemp);
	        dw_printf("Integer does not correspond to standard tone.\n");
	      }
	    }

	    strlcpy (temp, A->g_comment + match[0].rm_eo, sizeof(temp));
	    strlcpy (A->g_comment + match[0].rm_so, temp, sizeof(A->g_comment));
	  }
	  else if (regexec (&std_toff_re, A->g_comment, MAXMATCH, match, 0) == 0) {

	    dw_printf ("NO tone\n");
	    A->g_tone = 0;

	    strlcpy (temp, A->g_comment + match[0].rm_eo, sizeof(temp));
	    strlcpy (A->g_comment + match[0].rm_so, temp, sizeof(A->g_comment));
	  }
	  else if (regexec (&std_dcs_re, A->g_comment, MAXMATCH, match, 0) == 0) {

	    char sttemp[10];	/* three octal digits */

	    substr_se (sttemp, A->g_comment, match[1].rm_so, match[1].rm_eo);

	    A->g_dcs = strtoul (sttemp, NULL, 8);

	    strlcpy (temp, A->g_comment + match[0].rm_eo, sizeof(temp));
	    strlcpy (A->g_comment + match[0].rm_so, temp, sizeof(A->g_comment)-match[0].rm_so);
	  }
	  else if (regexec (&std_offset_re, A->g_comment, MAXMATCH, match, 0) == 0) {

	    char sttemp[10];	/* includes leading sign */

	    substr_se (sttemp, A->g_comment, match[1].rm_so, match[1].rm_eo);

	    A->g_offset = 10 * atoi(sttemp);

	    strlcpy (temp, A->g_comment + match[0].rm_eo, sizeof(temp));
	    strlcpy (A->g_comment + match[0].rm_so, temp, sizeof(A->g_comment)-match[0].rm_so);
	  }
	  else if (regexec (&std_range_re, A->g_comment, MAXMATCH, match, 0) == 0) {

	    char sttemp[10];	/* should be two digits */
	    char sutemp[10];	/* m for miles or k for km */

	    substr_se (sttemp, A->g_comment, match[1].rm_so, match[1].rm_eo);
	    substr_se (sutemp, A->g_comment, match[2].rm_so, match[2].rm_eo);

	    if (strcmp(sutemp, "m") == 0) {
	      A->g_range = atoi(sttemp);
	    }
	    else {
	      A->g_range = DW_KM_TO_MILES(atoi(sttemp));
	    }

	    strlcpy (temp, A->g_comment + match[0].rm_eo, sizeof(temp));
	    strlcpy (A->g_comment + match[0].rm_so, temp, sizeof(A->g_comment)-match[0].rm_so);
	  }
	  else {
	    keep_going = 0;
	  }
	}

/*
 * Telemetry data, in base 91 compressed format appears as 2 to 7 pairs
 * of base 91 digits, ! thru {, surrounded by | at start and end.
 */


	if (regexec (&base91_tel_re, A->g_comment, MAXMATCH, match, 0) == 0) 
	{

	  char tdata[30];	/* Should be even number of 4 to 14 characters. */

	  //dw_printf("compressed telemetry start=%d, end=%d\n", (int)(match[0].rm_so), (int)(match[0].rm_eo));

	  substr_se (tdata, A->g_comment, match[1].rm_so, match[1].rm_eo);

	  //dw_printf("compressed telemetry data = \"%s\"\n", tdata);

	  telemetry_data_base91 (A->g_src, tdata, A->g_telemetry, sizeof(A->g_telemetry));

	  strlcpy (temp, A->g_comment + match[0].rm_eo, sizeof(temp));
	  strlcpy (A->g_comment + match[0].rm_so, temp, sizeof(A->g_comment)-match[0].rm_so);
	}


/*
 * Latitude and Longitude in the form DD MM.HH has a resolution of about 60 feet.
 * The !DAO! option allows another digit or almost two for greater resolution.
 *
 * This would not make sense to use this with a compressed location which
 * already has much greater resolution.
 *
 * It surprised me to see this in a MIC-E message.
 * MIC-E has resolution of .01 minute so it would make sense to have it as an option.
 * We also find an example in  http://www.aprs.org/aprs12/mic-e-examples.txt
 *	'abc123R/'123}FFF.FFFMHztext.../A=123456...!DAO! Mv
 */

	if (regexec (&dao_re, A->g_comment, MAXMATCH, match, 0) == 0) 
	{

	  int d = A->g_comment[match[0].rm_so+1];
	  int a = A->g_comment[match[0].rm_so+2];
	  int o = A->g_comment[match[0].rm_so+3];

	  //dw_printf("DAO start=%d, end=%d\n", (int)(match[0].rm_so), (int)(match[0].rm_eo));


/*
 * Private extension for APRStt
 */

	  if (d == 'T') {

	    if (a == ' ' && o == ' ') {
	      snprintf (A->g_aprstt_loc, sizeof(A->g_aprstt_loc), "APRStt corral location");
	    }
	    else if (isdigit(a) && o == ' ') {
	      snprintf (A->g_aprstt_loc, sizeof(A->g_aprstt_loc), "APRStt location %c of 10", a);
	    }
	    else if (isdigit(a) && isdigit(o)) {
	      snprintf (A->g_aprstt_loc, sizeof(A->g_aprstt_loc), "APRStt location %c%c of 100", a, o);
	    }
	    else if (a == 'B' && isdigit(o)) {
	      snprintf (A->g_aprstt_loc, sizeof(A->g_aprstt_loc), "APRStt location %c%c...", a, o);
	    }

	  }
	  else if (isupper(d)) 
	  {
/*
 * This adds one extra digit to each.  Dao adds extra digit like:
 *
 *		Lat:	 DD MM.HHa
 *		Lon:	DDD HH.HHo
 */
 	    if (isdigit(a)) {
	      A->g_lat += (a - '0') / 60000.0 * sign(A->g_lat);
	    }
 	    if (isdigit(o)) {
	      A->g_lon += (o - '0') / 60000.0 * sign(A->g_lon);
	    }
	  }
	  else if (islower(d)) 
	  {
/*
 * This adds almost two extra digits to each like this:
 *
 *		Lat:	 DD MM.HHxx
 *		Lon:	DDD HH.HHxx
 *
 * The original character range '!' to '{' is first converted
 * to an integer in range of 0 to 90.  It is multiplied by 1.1
 * to stretch the numeric range to be 0 to 99.
 */

/*
 * Here are a couple situations where it is seen.
 *
 *	W8SAT-1>T2UV0P:`qC<0x1f>l!Xu\'"69}WMNI EDS Response Unit #1|+/%0'n|!w:X!|3
 *
 * Let's break that down into pieces.
 *
 *	W8SAT-1>T2UV0P:`qC<0x1f>l!Xu\'"69}		MIC-E format
 *							N 42 56.0000, W 085 39.0300,
 *							0 MPH, course 160, alt 709 ft
 *	WMNI EDS Response Unit #1			comment
 *	|+/%0'n|					base 91 telemetry
 *	!w:X!						DAO
 *	|3						Tiny Track 3
 *
 * Comment earlier points out that MIC-E format has resolution of 0.01 minute,
 * same as non-compressed format, so the DAO does work out, after thinking
 * about it for a while.
 * We also find a MIC-E example with !DAO! here:  http://www.aprs.org/aprs12/mic-e-examples.txt
 *
 * Another one:
 *
 *	KS4FUN-12>3X0PRU,W6CX-3,BKELEY,WIDE2*:`2^=l!<0x1c>+/'"48}MT-RTG|%B%p'a|!wqR!|3
 *
 *							MIC-E, Red Cross, Special
 *							N 38 00.2588, W 122 06.3354
 *							0 MPH, course 100, alt 108 ft
 *	MT-RTG						comment
 *	|%B%p'a|					Seq=397, A1=443, A2=610
 *	!wqR!						DAO
 *	|3						Byonics TinyTrack3
 *						
 */

/* 
 * The spec appears to be wrong.  It says '}' is the maximum value when it should be '{'. 
 */

 	    if (isdigit91(a)) {
	      A->g_lat += (a - B91_MIN) * 1.1 / 600000.0 * sign(A->g_lat);
	    }
 	    if (isdigit91(o)) {
	      A->g_lon += (o - B91_MIN) * 1.1 / 600000.0 * sign(A->g_lon);
	    }
	  }

	  strlcpy (temp, A->g_comment + match[0].rm_eo, sizeof(temp));
	  strlcpy (A->g_comment + match[0].rm_so, temp, sizeof(A->g_comment)-match[0].rm_so);
	}

/*
 * Altitude in feet.  /A=123456
 */

	if (regexec (&alt_re, A->g_comment, MAXMATCH, match, 0) == 0) 
	{

          //dw_printf("start=%d, end=%d\n", (int)(match[0].rm_so), (int)(match[0].rm_eo));

	  strlcpy (temp, A->g_comment + match[0].rm_eo, sizeof(temp));

	  A->g_comment[match[0].rm_eo] = '\0';
          A->g_altitude_ft = atoi(A->g_comment + match[0].rm_so + 3);

	  strlcpy (A->g_comment + match[0].rm_so, temp, sizeof(A->g_comment)-match[0].rm_so);
	}

	//dw_printf("Final comment='%s'\n", A->g_comment);

/*
 * Finally look for something that looks like frequency or CTCSS tone
 * in the remaining comment.  Point this out and suggest the 
 * standardized format.
 * Don't complain if we have already found a valid value.
 */
	if (A->g_freq == G_UNKNOWN && regexec (&bad_freq_re, A->g_comment, MAXMATCH, match, 0) == 0) 
	{
	  char bad[30];
	  char good[30];
	  double x;

	  substr_se (bad, A->g_comment, match[0].rm_so, match[0].rm_eo);
	  x = atof(bad);

	  if ((x >= 144 && x <= 148) ||
	      (x >= 222 && x <= 225) ||
	      (x >= 420 && x <= 450) ||
	      (x >= 902 && x <= 928)) { 

	    if ( ! A->g_quiet) {
	      snprintf (good, sizeof(good), "%07.3fMHz", x);
	      text_color_set(DW_COLOR_ERROR);
	      dw_printf("\"%s\" in comment looks like a frequency in non-standard format.\n", bad);
	      dw_printf("For most systems to recognize it, use exactly this form \"%s\" at beginning of comment.\n", good);
	    }
	    if (A->g_freq == G_UNKNOWN) {
	      A->g_freq = x;
	    }
	  }
	}

	if (A->g_tone == G_UNKNOWN && regexec (&bad_tone_re, A->g_comment, MAXMATCH, match, 0) == 0) 
	{
	  char bad1[30];	/* original 99.9 or 999.9 format or one of 67 77 100 123 */
	  char bad2[30];	/* 99.9 or 999.9 format.  ".0" appended for special cases. */
	  char good[30];
	  int i;

	  substr_se (bad1, A->g_comment, match[2].rm_so, match[2].rm_eo);
	  strlcpy (bad2, bad1, sizeof(bad2));
	  if (strcmp(bad2, "67") == 0 || strcmp(bad2, "77") == 0 || strcmp(bad2, "100") == 0 || strcmp(bad2, "123") == 0) {
	    strlcat (bad2, ".0", sizeof(bad2));
	  }

// TODO:  Why wasn't freq/PL recognized here?
// Should we recognize some cases of single decimal place as frequency?

//DECODED[194] N8VIM audio level = 27   [NONE]
//[0] N8VIM>BEACON,WIDE2-2:!4240.85N/07133.99W_PHG72604/ Pepperell, MA-> WX. 442.9+ PL100<0x0d>
//Didn't find wind direction in form c999.
//Didn't find wind speed in form s999.
//Didn't find wind gust in form g999.
//Didn't find temperature in form t999.
//Weather Report, WEATHER Station (blue)
//N 42 40.8500, W 071 33.9900
//, "PHG72604/ Pepperell, MA-> WX. 442.9+ PL100"


	  for (i = 0; i < NUM_CTCSS; i++) {
	    if (strcmp (s_ctcss[i], bad2) == 0) {

	      if ( ! A->g_quiet) {
                snprintf (good, sizeof(good), "T%03d", i_ctcss[i]);
	        text_color_set(DW_COLOR_ERROR);
	        dw_printf("\"%s\" in comment looks like it might be a CTCSS tone in non-standard format.\n", bad1);
	        dw_printf("For most systems to recognize it, use exactly this form \"%s\" at near beginning of comment, after any frequency.\n", good);
	      }
	      if (A->g_tone == G_UNKNOWN) {
	        A->g_tone = atof(bad2);
	      }
	      break;
	    }
	  }
	}

	if ((A->g_offset == 6000 || A->g_offset == -6000) && A->g_freq >= 144 && A->g_freq <= 148) {
	  if ( ! A->g_quiet) {
	    text_color_set(DW_COLOR_ERROR);
	    dw_printf("A transmit offset of 6 MHz on the 2 meter band doesn't seem right.\n");
	    dw_printf("Each unit is 10 kHz so you should probably be using \"-060\" or \"+060\"\n");
	  }
	}

/*
 * TODO: samples in zfreq-test4.txt
 */

}

/* end process_comment */





/*------------------------------------------------------------------
 *
 * Function:	main
 *
 * Purpose:	Main program for standalone test program.
 *
 * Inputs:	stdin for raw data to decode.
 *		This is in the usual display format either from
 *		a TNC, findu.com, aprs.fi, etc.  e.g.
 *
 *		N1EDF-9>T2QT8Y,W1CLA-1,WIDE1*,WIDE2-2,00000:`bSbl!Mv/`"4%}_ <0x0d>
 *
 *		WB2OSZ-1>APN383,qAR,N1EDU-2:!4237.14NS07120.83W#PHG7130Chelmsford, MA
 *
 *		New for 1.5:
 *
 *		Also allow hexadecimal bytes for raw AX.25 or KISS.  e.g.
 *
 *		00 82 a0 ae ae 62 60 e0 82 96 68 84 40 40 60 9c 68 b0 ae 86 40 e0 40 ae 92 88 8a 64 63 03 f0 3e 45 4d 36 34 6e 65 2f 23 20 45 63 68 6f 6c 69 6e 6b 20 31 34 35 2e 33 31 30 2f 31 30 30 68 7a 20 54 6f 6e 65
 *
 *		If it begins with 00 or C0 (which would be impossible for AX.25 address) process as KISS.
 *		Also print these formats.
 *
 * Outputs:	stdout
 *
 * Description:	Compile like this to make a standalone test program.
 *		Just run "make" and this will be built along with everything else.
 *		The point I'm trying to make is that DECAMAIN must be defined
 *		to enable the main program here for a standalone application.
 *
 *		gcc -o decode_aprs -DDECAMAIN decode_aprs.c ax25_pad.c ...
 *
 *		./decode_aprs < decode_aprs.txt
 *
 *		aprs.fi precedes raw data with a time stamp which you
 *		would need to remove first.
 *
 *		cut -c26-999 tmp/kj4etp-9.txt | decode_aprs.exe
 *
 *
 * Restriction:	MIC-E message type can be problematic because it
 *		it can use unprintable characters in the information field.
 *
 *		Dire Wolf and aprs.fi print it in hexadecimal.  Example:
 *
 *		KB1KTR-8>TR3U6T,KB1KTR-9*,WB2OSZ-1*,WIDE2*,qAR,W1XM:`c1<0x1f>l!t>/>"4^}
 *		                                                       ^^^^^^
 *		                                                       ||||||
 *		What does findu.com do in this case?
 *
 *		ax25_from_text recognizes this representation so it can be used
 *		to decode raw data later.
 *
 * TODO:	To make it more useful,
 *			- Remove any leading timestamp.
 *			- Remove any "qA*" and following from the path.
 *			- Handle non-APRS frames properly.
 *
 *------------------------------------------------------------------*/

#if DECAMAIN

#include "kiss_frame.h"



/* Stub for stand-alone decoder. */

void nmea_send_waypoint (char *wname_in, double dlat, double dlong, char symtab, char symbol,
                 float alt, float course, float speed, char *comment)
{
	return;
}

// TODO:  hex_dump is currently in server.c and we don't want to drag that in.
// Someday put it in a more reasonable place, with other general utilities, and remove the private copy here.


static void hex_dump (unsigned char *p, int len)
{
	int n, i, offset;

	offset = 0;
	while (len > 0) {
	  n = len < 16 ? len : 16;
	  dw_printf ("  %03x: ", offset);
	  for (i=0; i<n; i++) {
	    dw_printf (" %02x", p[i]);
	  }
	  for (i=n; i<16; i++) {
	    dw_printf ("   ");
	  }
	  dw_printf ("  ");
	  for (i=0; i<n; i++) {
	    dw_printf ("%c", isprint(p[i]) ? p[i] : '.');
	  }
	  dw_printf ("\n");
	  p += 16;
	  offset += 16;
	  len -= 16;
	}
}


// Do we have two hexadecimal digits followed by whitespace or end of line?

#define ISHEX2(x)  (isxdigit(x[0]) && isxdigit(x[1]) && (x[2] == '\0' || isspace(x[2])))

#define MAXLINE 9000
#define MAXBYTES 3000

int main (int argc, char *argv[]) 
{
	char stuff[MAXLINE];
	unsigned char bytes[MAXBYTES];
	int num_bytes;
	char *p;	
	packet_t pp;

#if __WIN32__

// Select UTF-8 code page for console output.
// http://msdn.microsoft.com/en-us/library/windows/desktop/ms686036(v=vs.85).aspx
// This is the default I see for windows terminal:  
// >chcp
// Active code page: 437

	//Restore on exit? oldcp = GetConsoleOutputCP();
	SetConsoleOutputCP(CP_UTF8);

#else

/*
 * Default on Raspian & Ubuntu Linux is fine.  Don't know about others.
 *
 * Should we look at LANG environment variable and issue a warning
 * if it doesn't look something like  en_US.UTF-8 ?
 */

#endif	
	if (argc >= 2) {
	  if (freopen (argv[1], "r", stdin) == NULL) {
	    fprintf(stderr, "Can't open %s for read.\n", argv[1]);
	    exit(1);
	  }
	}

	// If you don't like the text colors, use 0 instead of 1 here.
	text_color_init(1, 0);
	text_color_set(DW_COLOR_INFO);

	while (fgets(stuff, sizeof(stuff), stdin) != NULL) 
        {
	  p = stuff + strlen(stuff) - 1;
	  while (p >= stuff && (*p == '\r' || *p == '\n')) {
	    *p-- = '\0';
	  }

	  if (strlen(stuff) == 0 || stuff[0] == '#') 
          {
	    /* comment or blank line */
	    text_color_set(DW_COLOR_INFO);
	    dw_printf("%s\n", stuff);
	    continue;
          }
  	  else 
	  {
	    /* Try to process it. */

	    text_color_set(DW_COLOR_REC);
	    dw_printf("\n");
	    ax25_safe_print (stuff, -1, 0);
	    dw_printf("\n");

// Do we have monitor format, KISS, or AX.25 frame?

	    p = stuff;
	    while (isspace(*p)) p++;

	    if (ISHEX2(p)) {

// Collect a bunch of hexadecimal numbers.

	      num_bytes = 0;

	      while (ISHEX2(p) && num_bytes < MAXBYTES) {

	        bytes[num_bytes++] = strtoul(p, NULL, 16);
	        p += 2;
	        while (isspace(*p)) p++;
	      }

	      if (num_bytes == 0 || *p != '\0') {
	        text_color_set(DW_COLOR_ERROR);
	        dw_printf("Parse error around column %d.\n", (int)(long)(p - stuff) + 1);
	        dw_printf("Was expecting only space separated 2 digit hexadecimal numbers.\n\n");
	        continue;	// next line
	      }

// If we have 0xC0 at start, remove it and expect same at end.

	      if (bytes[0] == FEND) {

		if (num_bytes < 2 || bytes[1] != 0) {
	          text_color_set(DW_COLOR_ERROR);
	          dw_printf("Was expecting to find 00 after the initial C0.\n");
	          continue;
	        }

		if (bytes[num_bytes-1] == FEND) {
	          text_color_set(DW_COLOR_INFO);
	          dw_printf("Removing KISS FEND characters at beginning and end.\n");
		  int n;
	          for (n = 0; n < num_bytes-1; n++) {
	            bytes[n] = bytes[n+1];
	          }
	          num_bytes -= 2;
	        }
	        else {
	          text_color_set(DW_COLOR_INFO);
	          dw_printf("Removing KISS FEND character at beginning.  Was expecting another at end.\n");
		  int n;
	          for (n = 0; n < num_bytes-1; n++) {
	            bytes[n] = bytes[n+1];
	          }
	          num_bytes -= 1;
		}
	      }


	      if (bytes[0] == 0) {

// Treat as KISS.  Undo any KISS encoding.

	        unsigned char kiss_frame[MAXBYTES];
	        int kiss_len = num_bytes;

	        memcpy (kiss_frame, bytes, num_bytes);

	        text_color_set(DW_COLOR_DEBUG);
	        dw_printf ("--- KISS frame ---\n");
	        hex_dump (kiss_frame, kiss_len);

	        // Put FEND at end to keep kiss_unwrap happy.
	        // Having one at the beginning is optional.

	        kiss_frame[kiss_len++] = FEND;

		// In the more general case, we would need to include
	        // the command byte because it could be escaped.
	        // Here we know it is 0, so we take a short cut and
	        // remove it before, rather than after, the conversion.

	        num_bytes = kiss_unwrap (kiss_frame + 1, kiss_len - 1, bytes);
	      }

// Treat as AX.25.

	      alevel_t alevel;
	      memset (&alevel, 0, sizeof(alevel));

	      pp = ax25_from_frame(bytes, num_bytes, alevel);
	      if (pp != NULL) {
	        char addrs[120];
	        unsigned char *pinfo;
	        int info_len;
	        decode_aprs_t A;

	        text_color_set(DW_COLOR_DEBUG);
	        dw_printf ("--- AX.25 frame ---\n");
	        ax25_hex_dump (pp);
	        dw_printf ("-------------------\n");

	        ax25_format_addrs (pp, addrs);
	        text_color_set(DW_COLOR_DECODED);
	        dw_printf ("%s", addrs);

	        info_len = ax25_get_info (pp, &pinfo);
	        ax25_safe_print ((char *)pinfo, info_len, 1);	// Display non-ASCII to hexadecimal.
	        dw_printf ("\n");

	        decode_aprs (&A, pp, 0, NULL);			// Extract information into structure.

	        decode_aprs_print (&A);			// Now print it in human readable format.

	        (void)ax25_check_addresses(pp);		// Errors for invalid addresses.

	        ax25_delete (pp);
	      }
	      else {
	        text_color_set(DW_COLOR_ERROR);
	        dw_printf("Could not construct AX.25 frame from bytes supplied!\n\n");
	      }
	    }
	    else {

// Normal monitoring format.

	      pp = ax25_from_text(stuff, 1);
	      if (pp != NULL) {
	        decode_aprs_t A;

	        decode_aprs (&A, pp, 0, NULL);	// Extract information into structure.

	        decode_aprs_print (&A);		// Now print it in human readable format.

	        // This seems to be redundant because we used strict option
	        // when parsing the monitoring format text.
	        //(void)ax25_check_addresses(pp);	// Errors for invalid addresses.

	        // Future?  Add -d option to include hex dump and maybe KISS?

	        ax25_delete (pp);
	      }
	      else {
	        text_color_set(DW_COLOR_ERROR);
	        dw_printf("ERROR - Could not parse monitoring format input!\n\n");
	      }
	    }
	  }
	}
	return (0);
}

#endif /* DECAMAIN */

/* end decode_aprs.c */