annotate libutil/tfo_msg_enc.c @ 10:3c5734b88c20

sipout-test-v22 put together
author Mychaela Falconia <falcon@freecalypso.org>
date Thu, 07 Mar 2024 02:33:49 -0800
parents 35c0d9f03c0a
children
Ignore whitespace changes - Everywhere: Within whitespace: At end of lines:
rev   line source
0
35c0d9f03c0a beginning with sipout-test-voice,
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
1 /*
35c0d9f03c0a beginning with sipout-test-voice,
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
2 * The function implemented in this module encodes a GSM 08.62 Extension_Block.
35c0d9f03c0a beginning with sipout-test-voice,
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
3 */
35c0d9f03c0a beginning with sipout-test-voice,
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
4
35c0d9f03c0a beginning with sipout-test-voice,
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
5 #include <stdint.h>
35c0d9f03c0a beginning with sipout-test-voice,
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
6 #include "osmo_bits.h"
35c0d9f03c0a beginning with sipout-test-voice,
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
7
35c0d9f03c0a beginning with sipout-test-voice,
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
8 /*
35c0d9f03c0a beginning with sipout-test-voice,
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
9 * EFR TRAU parity
35c0d9f03c0a beginning with sipout-test-voice,
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
10 *
35c0d9f03c0a beginning with sipout-test-voice,
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
11 * g(x) = x^3 + x^1 + 1
35c0d9f03c0a beginning with sipout-test-voice,
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
12 */
35c0d9f03c0a beginning with sipout-test-voice,
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
13 static const struct osmo_crc8gen_code gsm0860_efr_crc3 = {
35c0d9f03c0a beginning with sipout-test-voice,
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
14 .bits = 3,
35c0d9f03c0a beginning with sipout-test-voice,
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
15 .poly = 0x3,
35c0d9f03c0a beginning with sipout-test-voice,
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
16 .init = 0x0,
35c0d9f03c0a beginning with sipout-test-voice,
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
17 .remainder = 0x7,
35c0d9f03c0a beginning with sipout-test-voice,
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
18 };
35c0d9f03c0a beginning with sipout-test-voice,
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
19
35c0d9f03c0a beginning with sipout-test-voice,
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
20 void
35c0d9f03c0a beginning with sipout-test-voice,
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
21 encode_tfo_ext_words(bits_2_10, bits_12_15, ex, out)
35c0d9f03c0a beginning with sipout-test-voice,
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
22 unsigned bits_2_10, bits_12_15, ex;
35c0d9f03c0a beginning with sipout-test-voice,
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
23 uint16_t *out;
35c0d9f03c0a beginning with sipout-test-voice,
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
24 {
35c0d9f03c0a beginning with sipout-test-voice,
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
25 ubit_t crc_in[13];
35c0d9f03c0a beginning with sipout-test-voice,
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
26 uint8_t crc;
35c0d9f03c0a beginning with sipout-test-voice,
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
27
35c0d9f03c0a beginning with sipout-test-voice,
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
28 uint16_to_bits(bits_2_10, crc_in, 9);
35c0d9f03c0a beginning with sipout-test-voice,
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
29 uint16_to_bits(bits_12_15, crc_in + 9, 4);
35c0d9f03c0a beginning with sipout-test-voice,
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
30 crc = osmo_crc8gen_compute_bits(&gsm0860_efr_crc3, crc_in, 13);
35c0d9f03c0a beginning with sipout-test-voice,
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
31 out[0] = bits_2_10;
35c0d9f03c0a beginning with sipout-test-voice,
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
32 out[1] = (bits_12_15 << 5) | (crc << 2) | ex;
35c0d9f03c0a beginning with sipout-test-voice,
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
33 }