annotate libcoding/gsm7_pack.c @ 33:a91fb88a57b2 default tip

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author Mychaela Falconia <falcon@freecalypso.org>
date Fri, 14 Jun 2024 20:29:17 +0000
parents 2d0082216916
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1 /*
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2 * This library module implements the function for packing septets into octets.
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3 */
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4
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5 #include <sys/types.h>
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6
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7 gsm7_pack(inbuf, outbuf, noctets)
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8 u_char *inbuf, *outbuf;
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9 unsigned noctets;
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10 {
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11 u_char *ip = inbuf, *op = outbuf;
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12 unsigned n, c;
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13
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14 for (n = 0; n < noctets; n++) {
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15 c = n % 7;
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16 *op++ = ((ip[1] << 7) | ip[0]) >> c;
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17 if (c == 6)
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18 ip += 2;
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19 else
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20 ip += 1;
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21 }
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22 }