nginx 1.0.9 *) Change: now the 0x7F-0x1F characters are escaped as \xXX in an access_log. *) Change: now SIGWINCH signal works only in daemon mode. *) Feature: "proxy/fastcgi/scgi/uwsgi_ignore_headers" directives support the following additional values: X-Accel-Limit-Rate, X-Accel-Buffering, X-Accel-Charset. *) Feature: decrease of memory consumption if SSL is used. *) Feature: accept filters are now supported on NetBSD. *) Feature: the "uwsgi_buffering" and "scgi_buffering" directives. Thanks to Peter Smit. *) Bugfix: a segmentation fault occurred on start or while reconfiguration if the "ssl" directive was used at http level and there was no "ssl_certificate" defined. *) Bugfix: some UTF-8 characters were processed incorrectly. Thanks to Alexey Kuts. *) Bugfix: the ngx_http_rewrite_module directives specified at "server" level were executed twice if no matching locations were defined. *) Bugfix: a socket leak might occurred if "aio sendfile" was used. *) Bugfix: connections with fast clients might be closed after send_timeout if file AIO was used. *) Bugfix: in the ngx_http_autoindex_module. *) Bugfix: the module ngx_http_mp4_module did not support seeking on 32-bit platforms. *) Bugfix: non-cacheable responses might be cached if "proxy_cache_bypass" directive was used. Thanks to John Ferlito. *) Bugfix: cached responses with an empty body were returned incorrectly; the bug had appeared in 0.8.31. *) Bugfix: 201 responses of the ngx_http_dav_module were incorrect; the bug had appeared in 0.8.32. *) Bugfix: in the "return" directive. *) Bugfix: the "ssl_verify_client", "ssl_verify_depth", and "ssl_prefer_server_ciphers" directives might work incorrectly if SNI was used.

/*
 * Copyright (C) Igor Sysoev
 */


#ifndef _NGX_EVENT_BUSY_LOCK_H_INCLUDED_
#define _NGX_EVENT_BUSY_LOCK_H_INCLUDED_


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

typedef struct ngx_event_busy_lock_ctx_s  ngx_event_busy_lock_ctx_t;

struct ngx_event_busy_lock_ctx_s {
    ngx_event_t                *event;
    ngx_event_handler_pt        handler;
    void                       *data;
    ngx_msec_t                  timer;

    unsigned                    locked:1;
    unsigned                    waiting:1;
    unsigned                    cache_updated:1;

    char                       *md5;
    ngx_int_t                   slot;

    ngx_event_busy_lock_ctx_t  *next;
};


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

    ngx_uint_t                  busy;
    ngx_uint_t                  max_busy;

    ngx_uint_t                  waiting;
    ngx_uint_t                  max_waiting;

    ngx_event_busy_lock_ctx_t  *events;
    ngx_event_busy_lock_ctx_t  *last;

#if (NGX_THREADS)
    ngx_mutex_t                *mutex;
#endif
} ngx_event_busy_lock_t;


ngx_int_t ngx_event_busy_lock(ngx_event_busy_lock_t *bl,
    ngx_event_busy_lock_ctx_t *ctx);
ngx_int_t ngx_event_busy_lock_cacheable(ngx_event_busy_lock_t *bl,
    ngx_event_busy_lock_ctx_t *ctx);
void ngx_event_busy_unlock(ngx_event_busy_lock_t *bl,
    ngx_event_busy_lock_ctx_t *ctx);
void ngx_event_busy_lock_cancel(ngx_event_busy_lock_t *bl,
    ngx_event_busy_lock_ctx_t *ctx);


#endif /* _NGX_EVENT_BUSY_LOCK_H_INCLUDED_ */