Core: fixed ngx_pcre_studies cleanup. If a configuration parsing fails for some reason, ngx_regex_module_init() is not called, and ngx_pcre_studies remained set despite the fact that the pool it was allocated from is already freed. This might result in a segmentation fault during runtime regular expression compilation, such as in SSI, for example, in the single process mode, or if a worker process died and was respawned from a master process in such an inconsistent state. Fix is to clear ngx_pcre_studies from the pool cleanup handler (which is anyway used to free JIT-compiled patterns).

/*
 * 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_ */