nginx 1.3.0 *) Feature: the "debug_connection" directive now supports IPv6 addresses and the "unix:" parameter. *) Feature: the "set_real_ip_from" directive and the "proxy" parameter of the "geo" directive now support IPv6 addresses. *) Feature: the "real_ip_recursive", "geoip_proxy", and "geoip_proxy_recursive" directives. *) Feature: the "proxy_recursive" parameter of the "geo" directive. *) Bugfix: a segmentation fault might occur in a worker process if the "resolver" directive was used. *) Bugfix: a segmentation fault might occur in a worker process if the "fastcgi_pass", "scgi_pass", or "uwsgi_pass" directives were used and backend returned incorrect response. *) Bugfix: a segmentation fault might occur in a worker process if the "rewrite" directive was used and new request arguments in a replacement used variables. *) Bugfix: nginx might hog CPU if the open file resource limit was reached. *) Bugfix: nginx might loop infinitely over backends if the "proxy_next_upstream" directive with the "http_404" parameter was used and there were backup servers specified in an upstream block. *) Bugfix: adding the "down" parameter of the "server" directive might cause unneeded client redistribution among backend servers if the "ip_hash" directive was used. *) Bugfix: socket leak. Thanks to Yichun Zhang. *) Bugfix: in the ngx_http_fastcgi_module.

/*
 * Copyright (C) Igor Sysoev
 * Copyright (C) Nginx, Inc.
 */


#ifndef _NGX_SHMTX_H_INCLUDED_
#define _NGX_SHMTX_H_INCLUDED_


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


typedef struct {
    ngx_atomic_t   lock;
#if (NGX_HAVE_POSIX_SEM)
    ngx_atomic_t   wait;
#endif
} ngx_shmtx_sh_t;


typedef struct {
#if (NGX_HAVE_ATOMIC_OPS)
    ngx_atomic_t  *lock;
#if (NGX_HAVE_POSIX_SEM)
    ngx_atomic_t  *wait;
    ngx_uint_t     semaphore;
    sem_t          sem;
#endif
#else
    ngx_fd_t       fd;
    u_char        *name;
#endif
    ngx_uint_t     spin;
} ngx_shmtx_t;


ngx_int_t ngx_shmtx_create(ngx_shmtx_t *mtx, ngx_shmtx_sh_t *addr,
    u_char *name);
void ngx_shmtx_destory(ngx_shmtx_t *mtx);
ngx_uint_t ngx_shmtx_trylock(ngx_shmtx_t *mtx);
void ngx_shmtx_lock(ngx_shmtx_t *mtx);
void ngx_shmtx_unlock(ngx_shmtx_t *mtx);
ngx_uint_t ngx_shmtx_force_unlock(ngx_shmtx_t *mtx, ngx_pid_t pid);


#endif /* _NGX_SHMTX_H_INCLUDED_ */