view src/http/ngx_http_busy_lock.h @ 4311:45272aab5eea

Unlock of shared memory zones on process crash. If process exited abnormally while holding lock on some shared memory zone - unlock it. It may be not safe thing to do (as crash with lock held may result in corrupted shared memory structure, and other processes will subsequently crash while trying to access shared data), therefore complain loudly if unlock succeeds.
author Maxim Dounin <mdounin@mdounin.ru>
date Wed, 23 Nov 2011 14:09:19 +0000
parents 4c43e25d11ea
children d620f497c50f
line wrap: on
line source


/*
 * Copyright (C) Igor Sysoev
 */


#ifndef _NGX_HTTP_BUSY_LOCK_H_INCLUDED_
#define _NGX_HTTP_BUSY_LOCK_H_INCLUDED_


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


typedef struct {
    u_char             *md5_mask;
    char               *md5;
    int                 cacheable;

    int                 busy;
    int                 max_busy;

    int                 waiting;
    int                 max_waiting;

    time_t              timeout;

    ngx_event_mutex_t  *mutex;
} ngx_http_busy_lock_t;


typedef struct {
    time_t         time;
    ngx_event_t   *event;
    void         (*event_handler)(ngx_event_t *ev);
    u_char        *md5;
    int            slot;
} ngx_http_busy_lock_ctx_t;


int ngx_http_busy_lock(ngx_http_busy_lock_t *bl, ngx_http_busy_lock_ctx_t *bc);
int ngx_http_busy_lock_cacheable(ngx_http_busy_lock_t *bl,
                                 ngx_http_busy_lock_ctx_t *bc, int lock);
void ngx_http_busy_unlock(ngx_http_busy_lock_t *bl,
                          ngx_http_busy_lock_ctx_t *bc);

char *ngx_http_set_busy_lock_slot(ngx_conf_t *cf, ngx_command_t *cmd,
                                  void *conf);


#endif /* _NGX_HTTP_BUSY_LOCK_H_INCLUDED_ */