Mercurial > hg > nginx
view src/stream/ngx_stream_variables.h @ 7969:84c60a3cd12a stable-1.20
Changed ngx_chain_update_chains() to test tag first (ticket #2248).
Without this change, aio used with HTTP/2 can result in connection hang,
as observed with "aio threads; aio_write on;" and proxying (ticket #2248).
The problem is that HTTP/2 updates buffers outside of the output filters
(notably, marks them as sent), and then posts a write event to call
output filters. If a filter does not call the next one for some reason
(for example, because of an AIO operation in progress), this might
result in a state when the owner of a buffer already called
ngx_chain_update_chains() and can reuse the buffer, while the same buffer
is still sitting in the busy chain of some other filter.
In the particular case a buffer was sitting in output chain's ctx->busy,
and was reused by event pipe. Output chain's ctx->busy was permanently
blocked by it, and this resulted in connection hang.
Fix is to change ngx_chain_update_chains() to skip buffers from other
modules unconditionally, without trying to wait for these buffers to
become empty.
author | Maxim Dounin <mdounin@mdounin.ru> |
---|---|
date | Sat, 30 Oct 2021 02:39:19 +0300 |
parents | 2a288909abc6 |
children |
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/* * Copyright (C) Igor Sysoev * Copyright (C) Nginx, Inc. */ #ifndef _NGX_STREAM_VARIABLES_H_INCLUDED_ #define _NGX_STREAM_VARIABLES_H_INCLUDED_ #include <ngx_config.h> #include <ngx_core.h> #include <ngx_stream.h> typedef ngx_variable_value_t ngx_stream_variable_value_t; #define ngx_stream_variable(v) { sizeof(v) - 1, 1, 0, 0, 0, (u_char *) v } typedef struct ngx_stream_variable_s ngx_stream_variable_t; typedef void (*ngx_stream_set_variable_pt) (ngx_stream_session_t *s, ngx_stream_variable_value_t *v, uintptr_t data); typedef ngx_int_t (*ngx_stream_get_variable_pt) (ngx_stream_session_t *s, ngx_stream_variable_value_t *v, uintptr_t data); #define NGX_STREAM_VAR_CHANGEABLE 1 #define NGX_STREAM_VAR_NOCACHEABLE 2 #define NGX_STREAM_VAR_INDEXED 4 #define NGX_STREAM_VAR_NOHASH 8 #define NGX_STREAM_VAR_WEAK 16 #define NGX_STREAM_VAR_PREFIX 32 struct ngx_stream_variable_s { ngx_str_t name; /* must be first to build the hash */ ngx_stream_set_variable_pt set_handler; ngx_stream_get_variable_pt get_handler; uintptr_t data; ngx_uint_t flags; ngx_uint_t index; }; #define ngx_stream_null_variable { ngx_null_string, NULL, NULL, 0, 0, 0 } ngx_stream_variable_t *ngx_stream_add_variable(ngx_conf_t *cf, ngx_str_t *name, ngx_uint_t flags); ngx_int_t ngx_stream_get_variable_index(ngx_conf_t *cf, ngx_str_t *name); ngx_stream_variable_value_t *ngx_stream_get_indexed_variable( ngx_stream_session_t *s, ngx_uint_t index); ngx_stream_variable_value_t *ngx_stream_get_flushed_variable( ngx_stream_session_t *s, ngx_uint_t index); ngx_stream_variable_value_t *ngx_stream_get_variable(ngx_stream_session_t *s, ngx_str_t *name, ngx_uint_t key); #if (NGX_PCRE) typedef struct { ngx_uint_t capture; ngx_int_t index; } ngx_stream_regex_variable_t; typedef struct { ngx_regex_t *regex; ngx_uint_t ncaptures; ngx_stream_regex_variable_t *variables; ngx_uint_t nvariables; ngx_str_t name; } ngx_stream_regex_t; typedef struct { ngx_stream_regex_t *regex; void *value; } ngx_stream_map_regex_t; ngx_stream_regex_t *ngx_stream_regex_compile(ngx_conf_t *cf, ngx_regex_compile_t *rc); ngx_int_t ngx_stream_regex_exec(ngx_stream_session_t *s, ngx_stream_regex_t *re, ngx_str_t *str); #endif typedef struct { ngx_hash_combined_t hash; #if (NGX_PCRE) ngx_stream_map_regex_t *regex; ngx_uint_t nregex; #endif } ngx_stream_map_t; void *ngx_stream_map_find(ngx_stream_session_t *s, ngx_stream_map_t *map, ngx_str_t *match); ngx_int_t ngx_stream_variables_add_core_vars(ngx_conf_t *cf); ngx_int_t ngx_stream_variables_init_vars(ngx_conf_t *cf); extern ngx_stream_variable_value_t ngx_stream_variable_null_value; extern ngx_stream_variable_value_t ngx_stream_variable_true_value; #endif /* _NGX_STREAM_VARIABLES_H_INCLUDED_ */