Mercurial > hg > nginx-quic
annotate src/core/ngx_crc.h @ 786:5dc3ba0d6388
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author | Igor Sysoev <igor@sysoev.ru> |
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date | Tue, 17 Oct 2006 12:47:14 +0000 |
parents | 5622cdd48e5b |
children | 604f9671fae6 |
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1 |
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2 /* |
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3 * Copyright (C) Igor Sysoev |
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4 */ |
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7 #ifndef _NGX_CRC_H_INCLUDED_ |
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8 #define _NGX_CRC_H_INCLUDED_ |
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11 /* 32-bit crc16 */ |
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12 |
776 | 13 static ngx_inline uint32_t |
14 ngx_crc(char *data, size_t len) | |
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15 { |
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16 uint32_t sum; |
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18 for (sum = 0; len; len--) { |
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20 /* |
776 | 21 * gcc 2.95.2 x86 and icc 7.1.006 compile |
22 * that operator into the single "rol" opcode, | |
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23 * msvc 6.0sp2 compiles it into four opcodes. |
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24 */ |
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25 sum = sum >> 1 | sum << 31; |
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26 |
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27 sum += *data++; |
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28 } |
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29 |
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30 return sum; |
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31 } |
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32 |
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33 |
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34 #endif /* _NGX_CRC_H_INCLUDED_ */ |