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27 lines
530 B
C
27 lines
530 B
C
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#ifndef _NGX_CRC_H_INCLUDED_
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#define _NGX_CRC_H_INCLUDED_
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/* 32-bit crc16 */
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ngx_inline static uint32_t ngx_crc(char *data, size_t len)
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{
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uint32_t sum;
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for (sum = 0; len; len--) {
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/*
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* gcc 2.95.2 x86 and icc 7.1.006 compile that operator
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* into the single rol opcode.
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* msvc 6.0sp2 compiles it into four opcodes.
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*/
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sum = sum >> 1 | sum << 31;
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sum += *data++;
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}
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return sum;
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}
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#endif /* _NGX_CRC_H_INCLUDED_ */
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