annotate libcoding/utf8_decode.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 a function that converts text input
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3 * from UTF-8 to ISO 8859-1, rejecting any input Unicode characters
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4 * that aren't in the 8859-1 range. The conversion in done in place.
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5 */
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6
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7 #include <sys/types.h>
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8
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9 utf8_to_latin1(buf)
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10 u_char *buf;
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11 {
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12 u_char *ip = buf, *op = buf;
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13 int c, c2;
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14
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15 while (c = *ip++) {
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16 if (c < 0x80) {
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17 *op++ = c;
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18 continue;
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19 }
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20 if (c != 0xC2 && c != 0xC3)
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21 return(-1);
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22 c2 = *ip++;
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23 if (c2 < 0x80 || c2 > 0xBF)
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24 return(-1);
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25 *op++ = ((c & 3) << 6) | (c2 & 0x3F);
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26 }
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27 *op = '\0';
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28 return(0);
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29 }