nginx 0.8.48 *) Change: now the "server_name" directive default value is an empty name "". Thanks to Gena Makhomed. *) Change: now the "server_name_in_redirect" directive default value is "off". *) Feature: the $geoip_dma_code, $geoip_area_code, and $geoip_region_name variables. Thanks to Christine McGonagle. *) Bugfix: the "proxy_pass", "fastcgi_pass", "uwsgi_pass", and "scgi_pass" directives were not inherited inside "limit_except" blocks. *) Bugfix: the "proxy_cache_min_uses", "fastcgi_cache_min_uses" "uwsgi_cache_min_uses", and "scgi_cache_min_uses" directives did not work; the bug had appeared in 0.8.46. *) Bugfix: the "fastcgi_split_path_info" directive used incorrectly captures, if only parts of an URI were captured. Thanks to Yuriy Taraday and Frank Enderle. *) Bugfix: the "rewrite" directive did not escape a ";" character during copying from URI to query string. Thanks to Daisuke Murase. *) Bugfix: the ngx_http_image_filter_module closed a connection, if an image was larger than "image_filter_buffer" size.

/*
 * Copyright (C) Igor Sysoev
 */


#include <ngx_config.h>
#include <ngx_core.h>


void
ngx_spinlock(ngx_atomic_t *lock, ngx_atomic_int_t value, ngx_uint_t spin)
{

#if (NGX_HAVE_ATOMIC_OPS)

    ngx_uint_t  i, n;

    for ( ;; ) {

        if (*lock == 0 && ngx_atomic_cmp_set(lock, 0, value)) {
            return;
        }

        if (ngx_ncpu > 1) {

            for (n = 1; n < spin; n <<= 1) {

                for (i = 0; i < n; i++) {
                    ngx_cpu_pause();
                }

                if (*lock == 0 && ngx_atomic_cmp_set(lock, 0, value)) {
                    return;
                }
            }
        }

        ngx_sched_yield();
    }

#else

#if (NGX_THREADS)

#error ngx_spinlock() or ngx_atomic_cmp_set() are not defined !

#endif

#endif

}