nginx 0.6.7 *) Change: now the paths specified in the "include", "auth_basic_user_file", "perl_modules", "ssl_certificate", "ssl_certificate_key", and "ssl_client_certificate" directives are relative to directory of nginx configuration file nginx.conf, but not to nginx prefix directory. *) Change: the --sysconfdir=PATH option in configure was canceled. *) Change: the special make target "upgrade1" was defined for online upgrade of 0.1.x versions. *) Feature: the "server_name" and "valid_referers" directives support regular expressions. *) Feature: the "server" directive in the "upstream" context supports the "backup" parameter. *) Feature: the ngx_http_perl_module supports the $r->discard_request_body. *) Feature: the "add_header Last-Modified ..." directive changes the "Last-Modified" response header line. *) Bugfix: if an response different than 200 was returned to an request with body and connection went to the keep-alive state after the request, then nginx returned 400 for the next request. *) Bugfix: a segmentation fault occurred in worker process if invalid address was set in the "auth_http" directive. *) Bugfix: now nginx uses default listen backlog value 511 on all platforms except FreeBSD. Thanks to Jiang Hong. *) Bugfix: a worker process may got caught in an endless loop, if an "server" inside "upstream" block was marked as "down"; bug appeared in 0.6.6. *) Bugfix: now Solaris sendfilev() is not used to transfer the client request body to FastCGI-server via the unix domain socket.

/*
 * Copyright (C) Igor Sysoev
 */


#ifndef _NGX_SHMTX_H_INCLUDED_
#define _NGX_SHMTX_H_INCLUDED_


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


typedef struct {
#if (NGX_HAVE_ATOMIC_OPS)
    ngx_atomic_t  *lock;
#else
    ngx_fd_t       fd;
    u_char        *name;
#endif
} ngx_shmtx_t;


ngx_int_t ngx_shmtx_create(ngx_shmtx_t *mtx, void *addr, u_char *name);


#if (NGX_HAVE_ATOMIC_OPS)

static ngx_inline ngx_uint_t
ngx_shmtx_trylock(ngx_shmtx_t *mtx)
{
    return (*mtx->lock == 0 && ngx_atomic_cmp_set(mtx->lock, 0, ngx_pid));
}

#define ngx_shmtx_lock(mtx)   ngx_spinlock((mtx)->lock, ngx_pid, 1024)

#define ngx_shmtx_unlock(mtx) (void) ngx_atomic_cmp_set((mtx)->lock, ngx_pid, 0)

#define ngx_shmtx_destory(mtx)


#else

static ngx_inline ngx_uint_t
ngx_shmtx_trylock(ngx_shmtx_t *mtx)
{
    ngx_err_t  err;

    err = ngx_trylock_fd(mtx->fd);

    if (err == 0) {
        return 1;
    }

    if (err == NGX_EAGAIN) {
        return 0;
    }

    ngx_log_abort(err, ngx_trylock_fd_n " failed");

    return 0;
}


static ngx_inline void
ngx_shmtx_lock(ngx_shmtx_t *mtx)
{
    ngx_err_t  err;

    err = ngx_lock_fd(mtx->fd);

    if (err == 0) {
        return;
    }

    ngx_log_abort(err, ngx_lock_fd_n " failed");
}


static ngx_inline void
ngx_shmtx_unlock(ngx_shmtx_t *mtx)
{
    ngx_err_t  err;

    err = ngx_unlock_fd(mtx->fd);

    if (err == 0) {
        return;
    }

    ngx_log_abort(err, ngx_unlock_fd_n " failed");
}


void ngx_shmtx_destory(ngx_shmtx_t *mtx);

#endif


#endif /* _NGX_SHMTX_H_INCLUDED_ */