view src/core/ngx_regex.h @ 5970:74edc0ccf27a

Core: fixed a race resulting in extra sem_post()'s. The mtx->wait counter was not decremented if we were able to obtain the lock right after incrementing it. This resulted in unneeded sem_post() calls, eventually leading to EOVERFLOW errors being logged, "sem_post() failed while wake shmtx (75: Value too large for defined data type)". To close the race, mtx->wait is now decremented if we obtain the lock right after incrementing it in ngx_shmtx_lock(). The result can become -1 if a concurrent ngx_shmtx_unlock() decrements mtx->wait before the added code does. However, that only leads to one extra iteration in the next call of ngx_shmtx_lock().
author Roman Arutyunyan <arut@nginx.com>
date Wed, 04 Feb 2015 16:22:43 +0300
parents 6e1a48bcf915
children 0b5f12d5c531
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/*
 * Copyright (C) Igor Sysoev
 * Copyright (C) Nginx, Inc.
 */


#ifndef _NGX_REGEX_H_INCLUDED_
#define _NGX_REGEX_H_INCLUDED_


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

#include <pcre.h>


#define NGX_REGEX_NO_MATCHED  PCRE_ERROR_NOMATCH   /* -1 */

#define NGX_REGEX_CASELESS    PCRE_CASELESS


typedef struct {
    pcre        *code;
    pcre_extra  *extra;
} ngx_regex_t;


typedef struct {
    ngx_str_t     pattern;
    ngx_pool_t   *pool;
    ngx_int_t     options;

    ngx_regex_t  *regex;
    int           captures;
    int           named_captures;
    int           name_size;
    u_char       *names;
    ngx_str_t     err;
} ngx_regex_compile_t;


typedef struct {
    ngx_regex_t  *regex;
    u_char       *name;
} ngx_regex_elt_t;


void ngx_regex_init(void);
ngx_int_t ngx_regex_compile(ngx_regex_compile_t *rc);

#define ngx_regex_exec(re, s, captures, size)                                \
    pcre_exec(re->code, re->extra, (const char *) (s)->data, (s)->len, 0, 0, \
              captures, size)
#define ngx_regex_exec_n      "pcre_exec()"

ngx_int_t ngx_regex_exec_array(ngx_array_t *a, ngx_str_t *s, ngx_log_t *log);


#endif /* _NGX_REGEX_H_INCLUDED_ */