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38 lines
947 B
C++
38 lines
947 B
C++
// < - ASRM
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#include "ais.h"
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namespace libais {
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Ais12::Ais12(const char *nmea_payload, const size_t pad)
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: AisMsg(nmea_payload, pad), seq_num(0), dest_mmsi(0), retransmitted(false),
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spare(0), spare2(0) {
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if (!CheckStatus()) {
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return;
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}
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// WARNING: The ITU 1371 specifications says the maximum number of bits is
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// 1008, but it appears that the maximum should be 1192.
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if (num_bits < 72 || num_bits > 1192) {
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status = AIS_ERR_BAD_BIT_COUNT;
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return;
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}
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assert(message_id == 12);
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bits.SeekTo(38);
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seq_num = bits.ToUnsignedInt(38, 2);
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dest_mmsi = bits.ToUnsignedInt(40, 30);
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retransmitted = bits[70];
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spare = bits[71];
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const int num_txt = (num_bits - 72) / 6;
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const int num_txt_bits = num_txt * 6;
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text = bits.ToString(72, num_txt_bits);
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if (bits.GetRemaining() > 0) {
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spare2 = bits.ToUnsignedInt(72 + num_txt_bits, bits.GetRemaining());
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}
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status = AIS_OK;
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}
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} // namespace libais
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