FreeCalypso > hg > gsm-codec-lib
view libgsmhr1/sid_detect.c @ 529:79cd992de3ad
libgsmfr2: API definitions for TFO transform
author | Mychaela Falconia <falcon@freecalypso.org> |
---|---|
date | Thu, 19 Sep 2024 08:07:26 +0000 |
parents | aaf4dec8bee0 |
children |
line wrap: on
line source
/* * The function in this module implements detection of perfect, error-free * HRv1 SID frames in TS 101 318 raw packed format. If SID is detected, * the return value is 2: the code for valid SID per GSM 06.41. */ #include <stdint.h> #include <string.h> #include "tw_gsmhr.h" int gsmhr_ts101318_is_perfect_sid(const uint8_t *payload) { static const uint8_t all_ff_bytes[9] = {0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF}; if ((payload[4] & 0x7F) != 0x7F) return 0; if (memcmp(payload + 5, all_ff_bytes, 9) == 0) return 2; else return 0; }