#ifndef _NGX_HTTP_CACHE_H_INCLUDED_
#define _NGX_HTTP_CACHE_H_INCLUDED_


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


typedef struct {
    time_t       expires;
    time_t       last_modified;
    time_t       date;
    off_t        length;
    size_t       key_len;
    char         key[1];
} ngx_http_cache_header_t;


typedef struct {
    uint32_t     crc;
    ngx_str_t    key;
    ngx_fd_t     fd;
    off_t        size;
    void        *data;          /* mmap, memory */
    time_t       accessed;
    time_t       last_modified;
    time_t       updated;       /* no needed with kqueue */
    int          refs;
    int          flags;
} ngx_http_cache_entry_t;

#define NGX_HTTP_CACHE_HASH   1021
#define NGX_HTTP_CACHE_NELTS  4

typedef struct {
    ngx_http_cache_entry_t  **cache;
    size_t                    hash;
    size_t                    nelts;
    time_t                    life_time;
    time_t                    check_time;
    ngx_pool_t               *pool;
} ngx_http_cache_hash_t;


typedef struct {
    ngx_http_cache_hash_t    *hash;
} ngx_http_cache_conf_t;


typedef struct {
    ngx_http_cache_hash_t    *hash;
    ngx_http_cache_entry_t   *cache;
    ngx_file_t                file;
    ngx_str_t                 key;
    uint32_t                  crc;
    u_char                    md5[16];
    ngx_path_t               *path;
    ngx_hunk_t               *buf;
    time_t                    expires;
    time_t                    last_modified;
    time_t                    date;
    off_t                     length;
    ssize_t                   header_size;
    size_t                    file_start;
    ngx_log_t                *log;
} ngx_http_cache_ctx_t;


#define NGX_HTTP_CACHE_STALE     1
#define NGX_HTTP_CACHE_AGED      2
#define NGX_HTTP_CACHE_THE_SAME  3


int ngx_http_cache_get_file(ngx_http_request_t *r, ngx_http_cache_ctx_t *ctx);
int ngx_http_cache_open_file(ngx_http_cache_ctx_t *ctx, ngx_file_uniq_t uniq);
int ngx_garbage_collector_http_cache_handler(ngx_gc_t *gc, ngx_str_t *name,
                                             ngx_dir_t *dir);
int ngx_http_cache_update_file(ngx_http_request_t *r,ngx_http_cache_ctx_t *ctx,
                               ngx_str_t *temp_file);



#endif /* _NGX_HTTP_CACHE_H_INCLUDED_ */