view src/core/ngx_crc.h @ 560:daf4847b43ff NGINX_0_8_32

nginx 0.8.32 *) Bugfix: UTF-8 encoding usage in the ngx_http_autoindex_module. Thanks to Maxim Dounin. *) Bugfix: regular expression named captures worked for two names only. Thanks to Maxim Dounin. *) Bugfix: now the "localhost" name is used in the "Host" request header line, if an unix domain socket is defined in the "auth_http" directive. Thanks to Maxim Dounin. *) Bugfix: nginx did nor support chunked transfer encoding for 201 responses. Thanks to Julian Reich. *) Bugfix: if the "expires modified" set date in the past, the a negative number was set in the "Cache-Control" response header line. Thanks to Alex Kapranoff.
author Igor Sysoev <http://sysoev.ru>
date Mon, 11 Jan 2010 00:00:00 +0300
parents fbf2b2f66c9f
children d0f7a625f27c
line wrap: on
line source


/*
 * Copyright (C) Igor Sysoev
 */


#ifndef _NGX_CRC_H_INCLUDED_
#define _NGX_CRC_H_INCLUDED_


#include <ngx_config.h>
#include <ngx_core.h>


/* 32-bit crc16 */

static ngx_inline uint32_t
ngx_crc(u_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_ */