annotate libgsmhr1/sid_detect.c @ 602:72cdae602d6e

libgsmhr1/dec_func.c: rm unused static functions In the original code, sp_dec.c held two kinds of functions: those needed only as part of the decoder, and those used by both decoder and encoder engines. In this library, we have moved the latter class of functions to dec_func.c module. Almost all static functions from the original sp_dec.c, with the exception of aToRc(), are needed only on sp_dec.c side of the new divide - remove them from dec_func.c, where they became dead code.
author Mychaela Falconia <falcon@freecalypso.org>
date Thu, 04 Dec 2025 18:58:22 +0000
parents aaf4dec8bee0
children
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aaf4dec8bee0 libgsmhr1: implement perfect SID detection
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1 /*
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2 * The function in this module implements detection of perfect, error-free
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3 * HRv1 SID frames in TS 101 318 raw packed format. If SID is detected,
aaf4dec8bee0 libgsmhr1: implement perfect SID detection
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4 * the return value is 2: the code for valid SID per GSM 06.41.
aaf4dec8bee0 libgsmhr1: implement perfect SID detection
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5 */
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6
aaf4dec8bee0 libgsmhr1: implement perfect SID detection
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7 #include <stdint.h>
aaf4dec8bee0 libgsmhr1: implement perfect SID detection
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8 #include <string.h>
aaf4dec8bee0 libgsmhr1: implement perfect SID detection
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9 #include "tw_gsmhr.h"
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10
aaf4dec8bee0 libgsmhr1: implement perfect SID detection
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11 int gsmhr_ts101318_is_perfect_sid(const uint8_t *payload)
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12 {
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13 static const uint8_t all_ff_bytes[9] = {0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
aaf4dec8bee0 libgsmhr1: implement perfect SID detection
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14 0xFF, 0xFF, 0xFF, 0xFF};
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15
aaf4dec8bee0 libgsmhr1: implement perfect SID detection
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16 if ((payload[4] & 0x7F) != 0x7F)
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17 return 0;
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18 if (memcmp(payload + 5, all_ff_bytes, 9) == 0)
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19 return 2;
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20 else
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21 return 0;
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22 }