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annotate libgsmhr1/sid_detect.c @ 585:3c6bf0d26ee7 default tip

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TW-TS-005 reader: fix maximum line length bug TW-TS-005 section 4.1 states: The maximum allowed length of each line is 80 characters, not including the OS-specific newline encoding. The implementation of this line length limit in the TW-TS-005 hex file reader function in the present suite was wrong, such that lines of the full maximum length could not be read. Fix it. Note that this bug affects comment lines too, not just actual RTP payloads. Neither Annex A nor Annex B features an RTP payload format that goes to the maximum of 40 bytes, but if a comment line goes to the maximum allowed length of 80 characters not including the terminating newline, the bug will be triggered, necessitating the present fix.
author Mychaela Falconia <falcon@freecalypso.org>
date Tue, 25 Feb 2025 07:49:28 +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
aaf4dec8bee0 libgsmhr1: implement perfect SID detection
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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>
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8 #include <string.h>
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9 #include "tw_gsmhr.h"
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10
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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 }