nginx 1.1.16 *) Change: the simultaneous subrequest limit has been raised to 200. *) Feature: the "from" parameter of the "disable_symlinks" directive. *) Feature: the "return" and "error_page" directives can be used to return 307 redirections. *) Bugfix: a segmentation fault might occur in a worker process if the "resolver" directive was used and there was no "error_log" directive specified at global level. Thanks to Roman Arutyunyan. *) Bugfix: a segmentation fault might occur in a worker process if the "proxy_http_version 1.1" or "fastcgi_keep_conn on" directives were used. *) Bugfix: memory leaks. Thanks to Lanshun Zhou. *) Bugfix: in the "disable_symlinks" directive. *) Bugfix: on ZFS filesystem disk cache size might be calculated incorrectly; the bug had appeared in 1.0.1. *) Bugfix: nginx could not be built by the icc 12.1 compiler. *) Bugfix: nginx could not be built by gcc on Solaris; the bug had appeared in 1.1.15.

/*
 * 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_ */