nginx 1.3.0 *) Feature: the "debug_connection" directive now supports IPv6 addresses and the "unix:" parameter. *) Feature: the "set_real_ip_from" directive and the "proxy" parameter of the "geo" directive now support IPv6 addresses. *) Feature: the "real_ip_recursive", "geoip_proxy", and "geoip_proxy_recursive" directives. *) Feature: the "proxy_recursive" parameter of the "geo" directive. *) Bugfix: a segmentation fault might occur in a worker process if the "resolver" directive was used. *) Bugfix: a segmentation fault might occur in a worker process if the "fastcgi_pass", "scgi_pass", or "uwsgi_pass" directives were used and backend returned incorrect response. *) Bugfix: a segmentation fault might occur in a worker process if the "rewrite" directive was used and new request arguments in a replacement used variables. *) Bugfix: nginx might hog CPU if the open file resource limit was reached. *) Bugfix: nginx might loop infinitely over backends if the "proxy_next_upstream" directive with the "http_404" parameter was used and there were backup servers specified in an upstream block. *) Bugfix: adding the "down" parameter of the "server" directive might cause unneeded client redistribution among backend servers if the "ip_hash" directive was used. *) Bugfix: socket leak. Thanks to Yichun Zhang. *) Bugfix: in the ngx_http_fastcgi_module.

/*
 * Copyright (C) Igor Sysoev
 * Copyright (C) Nginx, Inc.
 */


#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_ */