Mercurial > hg > nginx-quic
view src/http/ngx_http_cache.h @ 7514:319242d2ddc9
Upstream: background cache update before cache send (ticket #1782).
In case of filter finalization, essential request fields like r->uri,
r->args etc could be changed, which affected the cache update subrequest.
Also, after filter finalization r->cache could be set to NULL, leading to
null pointer dereference in ngx_http_upstream_cache_background_update().
The fix is to create background cache update subrequest before sending the
cached response.
Since initial introduction in 1aeaae6e9446 (1.11.10) background cache update
subrequest was created after sending the cached response because otherwise it
blocked the parent request output. In 9552758a786e (1.13.1) background
subrequests were introduced to eliminate the delay before sending the final
part of the cached response. This also made it possible to create the
background cache update subrequest before sending the response.
Note that creating the subrequest earlier does not change the fact that in case
of filter finalization the background cache update subrequest will likely not
have enough time to successfully update the cache entry. Filter finalization
leads to the main request termination as soon the current iteration of request
processing is complete.
| author | Roman Arutyunyan <arut@nginx.com> |
|---|---|
| date | Mon, 03 Jun 2019 20:33:26 +0300 |
| parents | 609daeb3b48b |
| children | ccb5ff87ab3e |
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/* * Copyright (C) Igor Sysoev * Copyright (C) Nginx, Inc. */ #ifndef _NGX_HTTP_CACHE_H_INCLUDED_ #define _NGX_HTTP_CACHE_H_INCLUDED_ #include <ngx_config.h> #include <ngx_core.h> #include <ngx_http.h> #define NGX_HTTP_CACHE_MISS 1 #define NGX_HTTP_CACHE_BYPASS 2 #define NGX_HTTP_CACHE_EXPIRED 3 #define NGX_HTTP_CACHE_STALE 4 #define NGX_HTTP_CACHE_UPDATING 5 #define NGX_HTTP_CACHE_REVALIDATED 6 #define NGX_HTTP_CACHE_HIT 7 #define NGX_HTTP_CACHE_SCARCE 8 #define NGX_HTTP_CACHE_KEY_LEN 16 #define NGX_HTTP_CACHE_ETAG_LEN 128 #define NGX_HTTP_CACHE_VARY_LEN 128 #define NGX_HTTP_CACHE_VERSION 5 typedef struct { ngx_uint_t status; time_t valid; } ngx_http_cache_valid_t; typedef struct { ngx_rbtree_node_t node; ngx_queue_t queue; u_char key[NGX_HTTP_CACHE_KEY_LEN - sizeof(ngx_rbtree_key_t)]; unsigned count:20; unsigned uses:10; unsigned valid_msec:10; unsigned error:10; unsigned exists:1; unsigned updating:1; unsigned deleting:1; unsigned purged:1; /* 10 unused bits */ ngx_file_uniq_t uniq; time_t expire; time_t valid_sec; size_t body_start; off_t fs_size; ngx_msec_t lock_time; } ngx_http_file_cache_node_t; struct ngx_http_cache_s { ngx_file_t file; ngx_array_t keys; uint32_t crc32; u_char key[NGX_HTTP_CACHE_KEY_LEN]; u_char main[NGX_HTTP_CACHE_KEY_LEN]; ngx_file_uniq_t uniq; time_t valid_sec; time_t updating_sec; time_t error_sec; time_t last_modified; time_t date; ngx_str_t etag; ngx_str_t vary; u_char variant[NGX_HTTP_CACHE_KEY_LEN]; size_t header_start; size_t body_start; off_t length; off_t fs_size; ngx_uint_t min_uses; ngx_uint_t error; ngx_uint_t valid_msec; ngx_uint_t vary_tag; ngx_buf_t *buf; ngx_http_file_cache_t *file_cache; ngx_http_file_cache_node_t *node; #if (NGX_THREADS || NGX_COMPAT) ngx_thread_task_t *thread_task; #endif ngx_msec_t lock_timeout; ngx_msec_t lock_age; ngx_msec_t lock_time; ngx_msec_t wait_time; ngx_event_t wait_event; unsigned lock:1; unsigned waiting:1; unsigned updated:1; unsigned updating:1; unsigned exists:1; unsigned temp_file:1; unsigned purged:1; unsigned reading:1; unsigned secondary:1; unsigned background:1; unsigned stale_updating:1; unsigned stale_error:1; }; typedef struct { ngx_uint_t version; time_t valid_sec; time_t updating_sec; time_t error_sec; time_t last_modified; time_t date; uint32_t crc32; u_short valid_msec; u_short header_start; u_short body_start; u_char etag_len; u_char etag[NGX_HTTP_CACHE_ETAG_LEN]; u_char vary_len; u_char vary[NGX_HTTP_CACHE_VARY_LEN]; u_char variant[NGX_HTTP_CACHE_KEY_LEN]; } ngx_http_file_cache_header_t; typedef struct { ngx_rbtree_t rbtree; ngx_rbtree_node_t sentinel; ngx_queue_t queue; ngx_atomic_t cold; ngx_atomic_t loading; off_t size; ngx_uint_t count; ngx_uint_t watermark; } ngx_http_file_cache_sh_t; struct ngx_http_file_cache_s { ngx_http_file_cache_sh_t *sh; ngx_slab_pool_t *shpool; ngx_path_t *path; off_t max_size; size_t bsize; time_t inactive; time_t fail_time; ngx_uint_t files; ngx_uint_t loader_files; ngx_msec_t last; ngx_msec_t loader_sleep; ngx_msec_t loader_threshold; ngx_uint_t manager_files; ngx_msec_t manager_sleep; ngx_msec_t manager_threshold; ngx_shm_zone_t *shm_zone; ngx_uint_t use_temp_path; /* unsigned use_temp_path:1 */ }; ngx_int_t ngx_http_file_cache_new(ngx_http_request_t *r); ngx_int_t ngx_http_file_cache_create(ngx_http_request_t *r); void ngx_http_file_cache_create_key(ngx_http_request_t *r); ngx_int_t ngx_http_file_cache_open(ngx_http_request_t *r); ngx_int_t ngx_http_file_cache_set_header(ngx_http_request_t *r, u_char *buf); void ngx_http_file_cache_update(ngx_http_request_t *r, ngx_temp_file_t *tf); void ngx_http_file_cache_update_header(ngx_http_request_t *r); ngx_int_t ngx_http_cache_send(ngx_http_request_t *); void ngx_http_file_cache_free(ngx_http_cache_t *c, ngx_temp_file_t *tf); time_t ngx_http_file_cache_valid(ngx_array_t *cache_valid, ngx_uint_t status); char *ngx_http_file_cache_set_slot(ngx_conf_t *cf, ngx_command_t *cmd, void *conf); char *ngx_http_file_cache_valid_set_slot(ngx_conf_t *cf, ngx_command_t *cmd, void *conf); extern ngx_str_t ngx_http_cache_status[]; #endif /* _NGX_HTTP_CACHE_H_INCLUDED_ */