Mercurial > hg > nginx
view src/stream/ngx_stream_variables.h @ 6806:75dbab4ea930
Events: improved error event handling for UDP sockets.
Normally, the epoll module calls the read and write handlers depending
on whether EPOLLIN and EPOLLOUT are reported by epoll_wait(). No error
processing is done in the module, the handlers are expected to get an
error when doing I/O.
If an error event is reported without EPOLLIN and EPOLLOUT, the module
set both EPOLLIN and EPOLLOUT to ensure the error event is handled at
least in one active handler.
This works well unless the error is delivered along with only one of
EPOLLIN or EPOLLOUT, and the corresponding handler does not do any I/O.
For example, it happened when getting EPOLLERR|EPOLLOUT from
epoll_wait() upon receiving "ICMP port unreachable" while proxying UDP.
As the write handler had nothing to send it was not able to detect and
log an error, and did not switch to the next upstream.
The fix is to unconditionally set EPOLLIN and EPOLLOUT in case of an
error event. In the aforementioned case, this causes the read handler
to be called which does recv() and detects an error.
In addition to the epoll module, analogous changes were made in
devpoll/eventport/poll.
author | Dmitry Volyntsev <xeioex@nginx.com> |
---|---|
date | Mon, 21 Nov 2016 16:03:42 +0300 |
parents | c70b7f4537e1 |
children | d2b2ff157da5 |
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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 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; }; 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_ */