view src/core/ngx_crc.h @ 416:b4f69f2ef02c NGINX_0_7_20

nginx 0.7.20 *) Changes in the ngx_http_gzip_filter_module. *) Feature: the ngx_http_limit_req_module. *) Bugfix: worker processes might exit on a SIGBUS signal on sparc and ppc platforms; the bug had appeared in 0.7.3. Thanks to Maxim Dounin. *) Bugfix: the "proxy_pass http://host/some:uri" directives did not work; the bug had appeared in 0.7.12. *) Bugfix: in HTTPS mode requests might fail with the "bad write retry" error. *) Bugfix: the ngx_http_secure_link_module did not work inside locations, whose names are less than 3 characters. *) Bugfix: $server_addr variable might have no value.
author Igor Sysoev <http://sysoev.ru>
date Mon, 10 Nov 2008 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_ */