nginx 0.7.47 *) Bugfix: nginx could not be built on FreeBSD 6 and early versions; the bug had appeared in 0.7.46. *) Bugfix: nginx could not be built on MacOSX; the bug had appeared in 0.7.46. *) Bugfix: if the "max_size" parameter was set, then the cache manager might purge a whole cache; the bug had appeared in 0.7.46. *) Change: a segmentation fault might occur in worker process, if the "proxy_cache"/"fastcgi_cache" and the "proxy_cache_valid"/ "fastcgi_cache_valid" were set on different levels; the bug had appeared in 0.7.46. *) Bugfix: a segmentation fault might occur in worker process, if a request was redirected to a proxied or FastCGI server via error_page or try_files; the bug had appeared in 0.7.44.

/*
 * 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_ */