| /* Licensed to the Apache Software Foundation (ASF) under one or more |
| * contributor license agreements. See the NOTICE file distributed with |
| * this work for additional information regarding copyright ownership. |
| * The ASF licenses this file to You under the Apache License, Version 2.0 |
| * (the "License"); you may not use this file except in compliance with |
| * the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| /** |
| * @file mod_cache.h |
| * @brief Main include file for the Apache Transparent Cache |
| * |
| * @defgroup MOD_CACHE mod_cache |
| * @ingroup APACHE_MODS |
| * @{ |
| */ |
| |
| #ifndef MOD_CACHE_H |
| #define MOD_CACHE_H |
| |
| #include "httpd.h" |
| #include "apr_date.h" |
| #include "apr_optional.h" |
| #include "apr_hooks.h" |
| |
| #include "cache_common.h" |
| |
| /* Create a set of CACHE_DECLARE(type), CACHE_DECLARE_NONSTD(type) and |
| * CACHE_DECLARE_DATA with appropriate export and import tags for the platform |
| */ |
| #if !defined(WIN32) |
| #define CACHE_DECLARE(type) type |
| #define CACHE_DECLARE_NONSTD(type) type |
| #define CACHE_DECLARE_DATA |
| #elif defined(CACHE_DECLARE_STATIC) |
| #define CACHE_DECLARE(type) type __stdcall |
| #define CACHE_DECLARE_NONSTD(type) type |
| #define CACHE_DECLARE_DATA |
| #elif defined(CACHE_DECLARE_EXPORT) |
| #define CACHE_DECLARE(type) __declspec(dllexport) type __stdcall |
| #define CACHE_DECLARE_NONSTD(type) __declspec(dllexport) type |
| #define CACHE_DECLARE_DATA __declspec(dllexport) |
| #else |
| #define CACHE_DECLARE(type) __declspec(dllimport) type __stdcall |
| #define CACHE_DECLARE_NONSTD(type) __declspec(dllimport) type |
| #define CACHE_DECLARE_DATA __declspec(dllimport) |
| #endif |
| |
| /* cache info information */ |
| typedef struct cache_info cache_info; |
| struct cache_info { |
| /** |
| * the original time corresponding to the 'Date:' header of the request |
| * served |
| */ |
| apr_time_t date; |
| /** a time when the cached entity is due to expire */ |
| apr_time_t expire; |
| /** r->request_time from the same request */ |
| apr_time_t request_time; |
| /** apr_time_now() at the time the entity was actually cached */ |
| apr_time_t response_time; |
| /** |
| * HTTP status code of the cached entity. Though not necessarily the |
| * status code finally issued to the request. |
| */ |
| int status; |
| /* cached cache-control */ |
| cache_control_t control; |
| }; |
| |
| /* cache handle information */ |
| typedef struct cache_object cache_object_t; |
| struct cache_object { |
| const char *key; |
| cache_object_t *next; |
| cache_info info; |
| /* Opaque portion (specific to the implementation) of the cache object */ |
| void *vobj; |
| }; |
| |
| typedef struct cache_handle cache_handle_t; |
| struct cache_handle { |
| cache_object_t *cache_obj; |
| apr_table_t *req_hdrs; /* cached request headers */ |
| apr_table_t *resp_hdrs; /* cached response headers */ |
| }; |
| |
| #define CACHE_PROVIDER_GROUP "cache" |
| |
| typedef struct { |
| int (*remove_entity) (cache_handle_t *h); |
| apr_status_t (*store_headers)(cache_handle_t *h, request_rec *r, cache_info *i); |
| apr_status_t (*store_body)(cache_handle_t *h, request_rec *r, apr_bucket_brigade *in, |
| apr_bucket_brigade *out); |
| apr_status_t (*recall_headers) (cache_handle_t *h, request_rec *r); |
| apr_status_t (*recall_body) (cache_handle_t *h, apr_pool_t *p, apr_bucket_brigade *bb); |
| int (*create_entity) (cache_handle_t *h, request_rec *r, |
| const char *urlkey, apr_off_t len, apr_bucket_brigade *bb); |
| int (*open_entity) (cache_handle_t *h, request_rec *r, |
| const char *urlkey); |
| int (*remove_url) (cache_handle_t *h, request_rec *r); |
| apr_status_t (*commit_entity)(cache_handle_t *h, request_rec *r); |
| apr_status_t (*invalidate_entity)(cache_handle_t *h, request_rec *r); |
| } cache_provider; |
| |
| typedef enum { |
| AP_CACHE_HIT, |
| AP_CACHE_REVALIDATE, |
| AP_CACHE_MISS, |
| AP_CACHE_INVALIDATE |
| } ap_cache_status_e; |
| |
| #define AP_CACHE_HIT_ENV "cache-hit" |
| #define AP_CACHE_REVALIDATE_ENV "cache-revalidate" |
| #define AP_CACHE_MISS_ENV "cache-miss" |
| #define AP_CACHE_INVALIDATE_ENV "cache-invalidate" |
| #define AP_CACHE_STATUS_ENV "cache-status" |
| |
| |
| /* cache_util.c */ |
| /* do a HTTP/1.1 age calculation */ |
| CACHE_DECLARE(apr_time_t) ap_cache_current_age(cache_info *info, const apr_time_t age_value, |
| apr_time_t now); |
| |
| CACHE_DECLARE(apr_time_t) ap_cache_hex2usec(const char *x); |
| CACHE_DECLARE(void) ap_cache_usec2hex(apr_time_t j, char *y); |
| CACHE_DECLARE(char *) ap_cache_generate_name(apr_pool_t *p, int dirlevels, |
| int dirlength, |
| const char *name); |
| CACHE_DECLARE(const char *)ap_cache_tokstr(apr_pool_t *p, const char *list, const char **str); |
| |
| /* Create a new table consisting of those elements from an |
| * headers table that are allowed to be stored in a cache. |
| */ |
| CACHE_DECLARE(apr_table_t *)ap_cache_cacheable_headers(apr_pool_t *pool, |
| apr_table_t *t, |
| server_rec *s); |
| |
| /* Create a new table consisting of those elements from an input |
| * headers table that are allowed to be stored in a cache. |
| */ |
| CACHE_DECLARE(apr_table_t *)ap_cache_cacheable_headers_in(request_rec *r); |
| |
| /* Create a new table consisting of those elements from an output |
| * headers table that are allowed to be stored in a cache; |
| * ensure there is a content type and capture any errors. |
| */ |
| CACHE_DECLARE(apr_table_t *)ap_cache_cacheable_headers_out(request_rec *r); |
| |
| /** |
| * Parse the Cache-Control and Pragma headers in one go, marking |
| * which tokens appear within the header. Populate the structure |
| * passed in. |
| */ |
| int ap_cache_control(request_rec *r, cache_control_t *cc, const char *cc_header, |
| const char *pragma_header, apr_table_t *headers); |
| |
| |
| /* hooks */ |
| |
| /** |
| * Cache status hook. |
| * This hook is called as soon as the cache has made a decision as to whether |
| * an entity should be served from cache (hit), should be served from cache |
| * after a successful validation (revalidate), or served from the backend |
| * and potentially cached (miss). |
| * |
| * A basic implementation of this hook exists in mod_cache which writes this |
| * information to the subprocess environment, and optionally to request |
| * headers. Further implementations may add hooks as appropriate to perform |
| * more advanced processing, or to store statistics about the cache behaviour. |
| */ |
| APR_DECLARE_EXTERNAL_HOOK(cache, CACHE, int, cache_status, (cache_handle_t *h, |
| request_rec *r, apr_table_t *headers, ap_cache_status_e status, |
| const char *reason)) |
| |
| APR_DECLARE_OPTIONAL_FN(apr_status_t, |
| ap_cache_generate_key, |
| (request_rec *r, apr_pool_t*p, const char **key)); |
| |
| |
| #endif /*MOD_CACHE_H*/ |
| /** @} */ |