view src/core/ngx_crc.h @ 300:cba14c1e2a4b NGINX_0_5_20

nginx 0.5.20 *) Feature: the "sendfile_max_chunk" directive. *) Feature: the "$http_...", "$sent_http_...", and "$upstream_http_..." variables may be changed using the "set" directive. *) Bugfix: a segmentation fault might occur in worker process if the SSI command 'if expr="$var = /"' was used. *) Bugfix: trailing boundary of multipart range response was transferred incorrectly. Thanks to Evan Miller. *) Bugfix: nginx did not work on Solaris/sparc64 if it was built by Sun Studio. Thanks to Andrei Nigmatulin. *) Bugfix: the ngx_http_perl_module could not built by Solaris make. Thanks to Andrei Nigmatulin.
author Igor Sysoev <http://sysoev.ru>
date Mon, 07 May 2007 00:00:00 +0400
parents fbf2b2f66c9f
children
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_ */