nginx 0.7.9 *) Change: now ngx_http_charset_module works by default with following MIME types: text/html, text/css, text/xml, text/plain, text/vnd.wap.wml, application/x-javascript, and application/rss+xml. *) Feature: the "charset_types" and "addition_types" directives. *) Feature: now the "gzip_types", "ssi_types", and "sub_filter_types" directives use hash. *) Feature: the ngx_cpp_test_module. *) Feature: the "expires" directive supports daily time. *) Feature: the ngx_http_xslt_module improvements and bug fixing. Thanks to Denis F. Latypoff and Maxim Dounin. *) Bugfix: the "log_not_found" directive did not work for index files tests. *) Bugfix: HTTPS connections might hang, if kqueue, epoll, rtsig, or eventport methods were used; the bug had appeared in 0.7.7. *) Bugfix: if the "server_name", "valid_referers", and "map" directives used an "*.domain.tld" wildcard and exact name "domain.tld" was not set, then the exact name was matched by the wildcard; the bugs had appeared in 0.3.18.

/*
 * 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

}