nginx/src/http/ngx_http_cache.h

   1
   2 /*
   3  * Copyright (C) Igor Sysoev
   4  */
   5
   6
   7 #ifndef _NGX_HTTP_CACHE_H_INCLUDED_
   8 #define _NGX_HTTP_CACHE_H_INCLUDED_
   9
  10
  11 #include <ngx_config.h>
  12 #include <ngx_core.h>
  13 #include <ngx_http.h>
  14
  15
  16 /*
  17  * The 3 bits allows the 7 uses before the cache entry allocation.
  18  * We can use maximum 7 bits, i.e up to the 127 uses.
  19  */
  20 #define NGX_HTTP_CACHE_LAZY_ALLOCATION_BITS  3
  21
  22
  23 typedef struct {
  24     uint32_t         crc;
  25     ngx_str_t        key;
  26     time_t           accessed;
  27
  28     unsigned         refs:20;    /* 1048576 references */
  29
  30     unsigned         count:NGX_HTTP_CACHE_LAZY_ALLOCATION_BITS;
  31
  32     unsigned         deleted:1;
  33     unsigned         expired:1;
  34     unsigned         memory:1;
  35     unsigned         mmap:1;
  36     unsigned         notify:1;
  37
  38     ngx_fd_t         fd;
  39 #if (NGX_USE_HTTP_FILE_CACHE_UNIQ)
  40     ngx_file_uniq_t  uniq;       /* no needed with kqueue */
  41 #endif
  42     time_t           last_modified;
  43     time_t           updated;
  44
  45     union {
  46         off_t        size;
  47         ngx_str_t    value;
  48     } data;
  49 } ngx_http_cache_entry_t;
  50
  51
  52 typedef struct {
  53     time_t       expires;
  54     time_t       last_modified;
  55     time_t       date;
  56     off_t        length;
  57     size_t       key_len;
  58     char         key[1];
  59 } ngx_http_cache_header_t;
  60
  61
  62 #define NGX_HTTP_CACHE_HASH   7
  63 #define NGX_HTTP_CACHE_NELTS  4
  64
  65 typedef struct {
  66     ngx_http_cache_entry_t   *elts;
  67     size_t                    hash;
  68     size_t                    nelts;
  69     time_t                    life;
  70     time_t                    update;
  71 #if (NGX_THREADS)
  72     ngx_mutex_t               mutex;
  73 #endif
  74     ngx_pool_t               *pool;
  75 } ngx_http_cache_hash_t;
  76
  77
  78 typedef struct {
  79     ngx_http_cache_hash_t    *hash;
  80     ngx_http_cache_entry_t   *cache;
  81     ngx_file_t                file;
  82     ngx_array_t               key;
  83     uint32_t                  crc;
  84     u_char                    md5[16];
  85     ngx_path_t               *path;
  86     ngx_buf_t                *buf;
  87     time_t                    expires;
  88     time_t                    last_modified;
  89     time_t                    date;
  90     off_t                     length;
  91     size_t                    key_len;
  92     size_t                    file_start;
  93     ngx_file_uniq_t           uniq;
  94     ngx_log_t                *log;
  95
  96     /* STUB */
  97     ssize_t                   header_size;
  98     ngx_str_t                 key0;
  99 } ngx_http_cache_t;
 100
 101
 102 typedef struct {
 103     ngx_path_t               *path;
 104     ngx_str_t                 key;
 105     ngx_buf_t                *buf;
 106
 107     unsigned                  file:1;
 108     unsigned                  memory:1;
 109     unsigned                  primary:1;
 110 } ngx_http_cache_ctx_t;
 111
 112
 113 #define NGX_HTTP_CACHE_STALE     1
 114 #define NGX_HTTP_CACHE_AGED      2
 115 #define NGX_HTTP_CACHE_THE_SAME  3
 116
 117
 118 ngx_int_t ngx_http_cache_get(ngx_http_request_t *r, ngx_http_cache_ctx_t *ctx);
 119
 120 ngx_int_t ngx_http_file_cache_get(ngx_http_request_t *r,
 121                                   ngx_http_cache_ctx_t *ctx);
 122
 123 ngx_int_t ngx_http_file_cache_open(ngx_http_cache_t *c);
 124
 125 ngx_int_t ngx_http_cache_cleaner_handler(ngx_gc_t *gc, ngx_str_t *name,
 126                                          ngx_dir_t *dir);
 127
 128
 129 #if 0
 130
 131 ngx_http_cache_t *ngx_http_cache_get(ngx_http_cache_hash_t *cache,
 132                                      ngx_http_cleanup_t *cleanup,
 133                                      ngx_str_t *key, uint32_t *crc);
 134
 135 ngx_http_cache_t *ngx_http_cache_alloc(ngx_http_cache_hash_t *hash,
 136                                        ngx_http_cache_t *cache,
 137                                        ngx_http_cleanup_t *cleanup,
 138                                        ngx_str_t *key, uint32_t crc,
 139                                        ngx_str_t *value, ngx_log_t *log);
 140 void ngx_http_cache_free(ngx_http_cache_t *cache,
 141                          ngx_str_t *key, ngx_str_t *value, ngx_log_t *log);
 142 void ngx_http_cache_lock(ngx_http_cache_hash_t *hash, ngx_http_cache_t *cache);
 143 void ngx_http_cache_unlock(ngx_http_cache_hash_t *hash,
 144                            ngx_http_cache_t *cache, ngx_log_t *log);
 145
 146 int ngx_http_cache_update_file(ngx_http_request_t *r,ngx_http_cache_ctx_t *ctx,
 147                                ngx_str_t *temp_file);
 148
 149 int ngx_http_send_cached(ngx_http_request_t *r);
 150
 151
 152 char *ngx_http_set_cache_slot(ngx_conf_t *cf, ngx_command_t *cmd, void *conf);
 153
 154 #endif
 155
 156
 157 #endif /* _NGX_HTTP_CACHE_H_INCLUDED_ */