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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 3afbc6c64172
children
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1 /*
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2 * This program regenerates a G.711 A-law encoding table equivalent to the
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3 * s2a[] table in the toast_alaw.c module in libgsm/toast; the intent is
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4 * to check that table for correctness. The "engine" function that does
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5 * the computation is based on alaw_compress() from ITU-T G.191 STL.
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6 */
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7
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8 #include <stdio.h>
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9 #include <stdlib.h>
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10
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11 static unsigned
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12 alaw_compress (input)
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13 unsigned input;
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14 {
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15 short ix, iexp;
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16
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17 ix = input >= 2048 /* 0 <= ix < 2048 */
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18 ? ~input & 2047 /* 1's complement for negative values */
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19 : input;
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20
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21 /* Do more, if exponent > 0 */
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22 if (ix > 15) { /* exponent=0 for ix <= 15 */
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23 iexp = 1; /* first step: */
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24 while (ix > 16 + 15) { /* find mantissa and exponent */
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25 ix >>= 1;
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26 iexp++;
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27 }
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28 ix -= 16; /* second step: remove leading '1' */
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29
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30 ix += iexp << 4; /* now compute encoded value */
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31 }
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32 if (input < 2048)
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33 ix |= (0x0080); /* add sign bit */
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34
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35 return ix ^ (0x0055); /* toggle even bits */
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36 }
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37
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38 main(argc, argv)
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39 char **argv;
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40 {
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41 unsigned input, output;
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42
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43 for (input = 0; input < 4096; input++) {
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44 if ((input & 15) == 0)
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45 putchar('\t');
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46 output = alaw_compress(input);
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47 printf("%3u,", output);
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48 if ((input & 15) == 15)
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49 putchar('\n');
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50 }
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51 exit(0);
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52 }