nginx 1.1.11 *) Feature: the "so_keepalive" parameter of the "listen" directive. Thanks to Vsevolod Stakhov. *) Feature: the "if_not_empty" parameter of the "fastcgi/scgi/uwsgi_param" directives. *) Feature: the $https variable. *) Feature: the "proxy_redirect" directive supports variables in the first parameter. *) Feature: the "proxy_redirect" directive supports regular expressions. *) Bugfix: the $sent_http_cache_control variable might contain a wrong value if the "expires" directive was used. Thanks to Yichun Zhang. *) Bugfix: the "read_ahead" directive might not work combined with "try_files" and "open_file_cache". *) Bugfix: a segmentation fault might occur in a worker process if small time was used in the "inactive" parameter of the "proxy_cache_path" directive. *) Bugfix: responses from cache might hang.

/*
 * 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_ */