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