nginx-0.3.18-RELEASE import *) Feature: the "server_names" directive supports the ".domain.tld" names. *) Feature: the "server_names" directive uses the hash for the "*.domain.tld" names and more effective hash for usual names. *) Change: the "server_names_hash_max_size" and "server_names_hash_bucket_size" directives. *) Change: the "server_names_hash" and "server_names_hash_threshold" directives were canceled. *) Feature: the "valid_referers" directive uses the hash site names. *) Change: now the "valid_referers" directive checks the site names only without the URI part. *) Bugfix: some ".domain.tld" names incorrectly processed by the ngx_http_map_module. *) Bugfix: segmentation fault was occurred if configuration file did not exist; the bug had appeared in 0.3.12. *) Bugfix: on 64-bit platforms segmentation fault may occurred on start; the bug had appeared in 0.3.16.

/*
 * Copyright (C) Igor Sysoev
 */


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


/*
 * TODO: the P4 optimized assembler version with the "pause" operation
 */

void
ngx_spinlock(ngx_atomic_t *lock, ngx_uint_t spin)
{

#if (NGX_HAVE_ATOMIC_OPS)

    ngx_uint_t  tries;

    tries = 0;

    for ( ;; ) {

        if (*lock) {
            if (ngx_ncpu > 1 && tries++ < spin) {
                continue;
            }

            ngx_sched_yield();

            tries = 0;

        } else {
            if (ngx_atomic_cmp_set(lock, 0, 1)) {
                return;
            }
        }
    }

#else

#if (NGX_THREADS)

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

#endif

#endif

}