4 * Piotr Fusik, 18.11.2001
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9 int uncompress (char* dest, unsigned* destLen,
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10 const char* source, unsigned sourceLen)
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15 /* source[0]: Compression method and flags
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16 bits 0 to 3: Compression method (must be Z_DEFLATED)
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17 bits 4 to 7: Compression info (must be <= 7)
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19 bits 0 to 4: Check bits
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20 bit 5: Preset dictionary (not supported, sorry)
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21 bits 6 to 7: Compression level
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23 if ((source[0] & 0x8f) != Z_DEFLATED || source[1] & 0x20)
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24 return Z_DATA_ERROR;
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25 if ((((unsigned) source[0] << 8) | (unsigned char) source[1]) % 31)
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26 return Z_DATA_ERROR;
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27 *destLen = len = inflatemem(dest, source + 2);
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28 ptr = (unsigned char*) source + sourceLen - 4;
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29 csum = adler32(adler32(0L, Z_NULL, 0), dest, len);
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30 if ((unsigned char) csum != ptr[3]
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31 || (unsigned char) (csum >> 8) != ptr[2]
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32 || (unsigned char) (csum >> 16) != ptr[1]
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33 || (unsigned char) (csum >> 24) != ptr[0])
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34 return Z_DATA_ERROR;
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