nginx-0.1.16-RELEASE import *) Bugfix: if the response were transferred by chunks, then on the HEAD request the final chunk was issued. *) Bugfix: the "Connection: keep-alive" header were issued, even if the keepalive_timeout directive forbade the keep-alive use. *) Bugfix: the errors in the ngx_http_fastcgi_module caused the segmentation faults. *) Bugfix: the compressed response encrypted by SSL may not transferred complete. *) Bugfix: the TCP-specific TCP_NODELAY, TCP_NOPSUH, and TCP_CORK options, are not used for the unix domain sockets. *) Feature: the rewrite directive supports the arguments rewriting. *) Bugfix: the response code 400 was returned for the POST request with the "Content-Length: 0" header; the bug had appeared in 0.1.14.

/*
 * Copyright (C) Igor Sysoev
 */


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


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

}