Skip to content

Commit

Permalink
Better interpretation of bulletin identifiers.
Browse files Browse the repository at this point in the history
  • Loading branch information
wb2osz committed Jun 3, 2023
1 parent 4008153 commit f9cf42b
Show file tree
Hide file tree
Showing 2 changed files with 51 additions and 4 deletions.
53 changes: 49 additions & 4 deletions src/decode_aprs.c
Original file line number Diff line number Diff line change
Expand Up @@ -1628,10 +1628,15 @@ static void aprs_mic_e (decode_aprs_t *A, packet_t pp, unsigned char *info, int
* 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.
* Is it an elegant generalization to lump all of these special cases
* together or was it a big mistake that will cause confusion and incorrect
* implementations? The decision to put telemetry metadata here is baffling.
*
*
* Cases: :xxxxxxxxx:PARM. Telemetry metadata, parameter name
* Cases: :BLNxxxxxx: ... Bulletin.
* :NWSxxxxxx: ... National Weather Service Bulletin.
*
* :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
Expand Down Expand Up @@ -1736,6 +1741,46 @@ static void aprs_message (decode_aprs_t *A, unsigned char *info, int ilen, int q

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

/*
* Addressee starting with BLN or NWS is a bulletin.
*/
if (strlen(addressee) >= 3 && strncmp(addressee,"BLN",3) == 0) {

// Interpret 3 cases of identifiers.
// BLN9 "general bulletin" has a single digit.
// BLNX "announcement" has a single uppercase letter.
// BLN9xxxxx "group bulletin" has single digit group id and group name up to 5 characters.

if (strlen(addressee) == 4 && isdigit(addressee[3])) {
snprintf (A->g_data_type_desc, sizeof(A->g_data_type_desc), "General Bulletin with identifier \"%s\"", addressee+3);
}
else if (strlen(addressee) == 4 && isupper(addressee[3])) {
snprintf (A->g_data_type_desc, sizeof(A->g_data_type_desc), "Announcement with identifier \"%s\"", addressee+3);
}
if (strlen(addressee) >=5 && isdigit(addressee[3])) {
snprintf (A->g_data_type_desc, sizeof(A->g_data_type_desc), "Group Bulletin with identifier \"%c\", group name \"%s\"", addressee[3], addressee+4);
}
else {
// Not one of the official formats.
snprintf (A->g_data_type_desc, sizeof(A->g_data_type_desc), "Bulletin with identifier \"%s\"", addressee+3);
}
A->g_message_subtype = message_subtype_bulletin;
strlcpy (A->g_comment, p->message, sizeof(A->g_comment));
}

else if (strlen(addressee) >= 3 && strncmp(addressee,"NWS",3) == 0) {
// NWS-xxxxx

if (strlen(addressee) >=4 && addressee[3] == '-') {
snprintf (A->g_data_type_desc, sizeof(A->g_data_type_desc), "NWS bulletin with identifier \"%s\"", addressee+4);
}
else {
snprintf (A->g_data_type_desc, sizeof(A->g_data_type_desc), "NWS bulletin with identifier \"%s\", missing - after NWS", addressee+3);
}
A->g_message_subtype = message_subtype_nws;
strlcpy (A->g_comment, p->message, sizeof(A->g_comment));
}


/*
* Special message formats contain telemetry metadata.
Expand All @@ -1748,7 +1793,7 @@ static void aprs_message (decode_aprs_t *A, unsigned char *info, int ilen, int q
* Why not use other characters after the "T" for metadata?
*/

if (strncmp(p->message,"PARM.",5) == 0) {
else 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);
Expand Down Expand Up @@ -1847,7 +1892,7 @@ static void aprs_message (decode_aprs_t *A, unsigned char *info, int ilen, int q
// X>Y:}A>B::WA1XYX-15:Howdy y'all{toolong

else {
// Look for message number.
// Normal messaage case. Look for message number.
char *pno = strchr(p->message, '{');
if (pno != NULL) {
strlcpy (A->g_message_number, pno+1, sizeof(A->g_message_number));
Expand Down
2 changes: 2 additions & 0 deletions src/decode_aprs.h
Original file line number Diff line number Diff line change
Expand Up @@ -70,6 +70,8 @@ typedef struct decode_aprs_s {
message_subtype_message,
message_subtype_ack,
message_subtype_rej,
message_subtype_bulletin,
message_subtype_nws,
message_subtype_telem_parm,
message_subtype_telem_unit,
message_subtype_telem_eqns,
Expand Down

0 comments on commit f9cf42b

Please sign in to comment.