Core: free shared memory zones only after reconfiguration. This is what usually happens for zones no longer used in the new configuration, but zones where size or tag were changed were freed when creating new memory zones. If reconfiguration failed (for example, due to a conflicting listening socket), this resulted in a segmentation fault in the master process. Reported by Zhihua Cao, http://mailman.nginx.org/pipermail/nginx-devel/2017-October/010536.html.

/*
 * Copyright (C) Ruslan Ermilov
 * Copyright (C) Nginx, Inc.
 */


#ifndef _NGX_RWLOCK_H_INCLUDED_
#define _NGX_RWLOCK_H_INCLUDED_


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


void ngx_rwlock_wlock(ngx_atomic_t *lock);
void ngx_rwlock_rlock(ngx_atomic_t *lock);
void ngx_rwlock_unlock(ngx_atomic_t *lock);
void ngx_rwlock_downgrade(ngx_atomic_t *lock);


#endif /* _NGX_RWLOCK_H_INCLUDED_ */