nginx 0.5.1 *) Bugfix: the "post_action" directive might not run after a unsuccessful completion of a request. *) Workaround: for Eudora for Mac; bug appeared in 0.4.11. Thanks to Bron Gondwana. *) Bugfix: if the "upstream" name was used in the "fastcgi_pass", then the message "no port in upstream" was issued; bug appeared in 0.5.0. *) Bugfix: if the "proxy_pass" and "fastcgi_pass" directives used the same servers but different ports, then these directives uses the first described port; bug appeared in 0.5.0. *) Bugfix: if the "proxy_pass" and "fastcgi_pass" directives used the unix domain sockets, then these directives used first described socket; bug appeared in 0.5.0. *) Bugfix: ngx_http_auth_basic_module ignored the user if it was in the last line in the password file and there was no the carriage return, the line feed, or the ":" symbol after the password. *) Bugfix: the $upstream_response_time variable might be equal to "0.000", although response time was more than 1 millisecond.

/*
 * 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

}