1
0
mirror of https://github.com/peterantypas/maiana.git synced 2025-05-15 23:10:11 -07:00
2021-09-09 08:14:28 -07:00

60 lines
1.5 KiB
C++

// Class B static data report. Can be one of 4 different parts. Only
// A and B defined for ITU 1371-3
#include "ais.h"
namespace libais {
Ais24::Ais24(const char *nmea_payload, const size_t pad)
: AisMsg(nmea_payload, pad), part_num(0), type_and_cargo(0),
dim_a(0), dim_b(0), dim_c(0), dim_d(0), spare(0) {
if (!CheckStatus()) {
return;
}
if (num_bits != 160 && num_bits != 168) {
status = AIS_ERR_BAD_BIT_COUNT;
return;
}
assert(message_id == 24);
bits.SeekTo(38);
part_num = bits.ToUnsignedInt(38, 2);
switch (part_num) {
case 0: // Part A
name = bits.ToString(40, 120);
if (num_bits == 168) {
// Accept the invalid size.
spare = bits.ToUnsignedInt(160, 8);
}
break;
case 1: // Part B
if (num_bits == 160) {
// Some devices incorrectly use part 1 as 0.
name = bits.ToString(40, 120);
part_num = 0;
break;
}
type_and_cargo = bits.ToUnsignedInt(40, 8);
vendor_id = bits.ToString(48, 42);
callsign = bits.ToString(90, 42);
dim_a = bits.ToUnsignedInt(132, 9);
dim_b = bits.ToUnsignedInt(141, 9);
dim_c = bits.ToUnsignedInt(150, 6);
dim_d = bits.ToUnsignedInt(156, 6);
spare = bits.ToUnsignedInt(162, 6);
break;
case 2: // FALLTHROUGH - Not defined by ITU 1371-5
case 3: // FALLTHROUGH - Not defined by ITU 1371-5
default:
status = AIS_ERR_BAD_MSG_CONTENT;
return;
}
assert(bits.GetRemaining() == 0);
status = AIS_OK;
}
} // namespace libais