Mercurial > hg > nginx-quic
view src/http/ngx_http_variables.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 | 2a288909abc6 |
children | 08b3ea81ff5f |
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/* * Copyright (C) Igor Sysoev * Copyright (C) Nginx, Inc. */ #ifndef _NGX_HTTP_VARIABLES_H_INCLUDED_ #define _NGX_HTTP_VARIABLES_H_INCLUDED_ #include <ngx_config.h> #include <ngx_core.h> #include <ngx_http.h> typedef ngx_variable_value_t ngx_http_variable_value_t; #define ngx_http_variable(v) { sizeof(v) - 1, 1, 0, 0, 0, (u_char *) v } typedef struct ngx_http_variable_s ngx_http_variable_t; typedef void (*ngx_http_set_variable_pt) (ngx_http_request_t *r, ngx_http_variable_value_t *v, uintptr_t data); typedef ngx_int_t (*ngx_http_get_variable_pt) (ngx_http_request_t *r, ngx_http_variable_value_t *v, uintptr_t data); #define NGX_HTTP_VAR_CHANGEABLE 1 #define NGX_HTTP_VAR_NOCACHEABLE 2 #define NGX_HTTP_VAR_INDEXED 4 #define NGX_HTTP_VAR_NOHASH 8 #define NGX_HTTP_VAR_WEAK 16 #define NGX_HTTP_VAR_PREFIX 32 struct ngx_http_variable_s { ngx_str_t name; /* must be first to build the hash */ ngx_http_set_variable_pt set_handler; ngx_http_get_variable_pt get_handler; uintptr_t data; ngx_uint_t flags; ngx_uint_t index; }; #define ngx_http_null_variable { ngx_null_string, NULL, NULL, 0, 0, 0 } ngx_http_variable_t *ngx_http_add_variable(ngx_conf_t *cf, ngx_str_t *name, ngx_uint_t flags); ngx_int_t ngx_http_get_variable_index(ngx_conf_t *cf, ngx_str_t *name); ngx_http_variable_value_t *ngx_http_get_indexed_variable(ngx_http_request_t *r, ngx_uint_t index); ngx_http_variable_value_t *ngx_http_get_flushed_variable(ngx_http_request_t *r, ngx_uint_t index); ngx_http_variable_value_t *ngx_http_get_variable(ngx_http_request_t *r, ngx_str_t *name, ngx_uint_t key); ngx_int_t ngx_http_variable_unknown_header(ngx_http_variable_value_t *v, ngx_str_t *var, ngx_list_part_t *part, size_t prefix); #if (NGX_PCRE) typedef struct { ngx_uint_t capture; ngx_int_t index; } ngx_http_regex_variable_t; typedef struct { ngx_regex_t *regex; ngx_uint_t ncaptures; ngx_http_regex_variable_t *variables; ngx_uint_t nvariables; ngx_str_t name; } ngx_http_regex_t; typedef struct { ngx_http_regex_t *regex; void *value; } ngx_http_map_regex_t; ngx_http_regex_t *ngx_http_regex_compile(ngx_conf_t *cf, ngx_regex_compile_t *rc); ngx_int_t ngx_http_regex_exec(ngx_http_request_t *r, ngx_http_regex_t *re, ngx_str_t *s); #endif typedef struct { ngx_hash_combined_t hash; #if (NGX_PCRE) ngx_http_map_regex_t *regex; ngx_uint_t nregex; #endif } ngx_http_map_t; void *ngx_http_map_find(ngx_http_request_t *r, ngx_http_map_t *map, ngx_str_t *match); ngx_int_t ngx_http_variables_add_core_vars(ngx_conf_t *cf); ngx_int_t ngx_http_variables_init_vars(ngx_conf_t *cf); extern ngx_http_variable_value_t ngx_http_variable_null_value; extern ngx_http_variable_value_t ngx_http_variable_true_value; #endif /* _NGX_HTTP_VARIABLES_H_INCLUDED_ */