Mercurial > hg > nginx
view src/core/ngx_open_file_cache.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 | 47ece8818978 |
| children |
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/* * Copyright (C) Igor Sysoev * Copyright (C) Nginx, Inc. */ #include <ngx_config.h> #include <ngx_core.h> #ifndef _NGX_OPEN_FILE_CACHE_H_INCLUDED_ #define _NGX_OPEN_FILE_CACHE_H_INCLUDED_ #define NGX_OPEN_FILE_DIRECTIO_OFF NGX_MAX_OFF_T_VALUE typedef struct { ngx_fd_t fd; ngx_file_uniq_t uniq; time_t mtime; off_t size; off_t fs_size; off_t directio; size_t read_ahead; ngx_err_t err; char *failed; time_t valid; ngx_uint_t min_uses; #if (NGX_HAVE_OPENAT) size_t disable_symlinks_from; unsigned disable_symlinks:2; #endif unsigned test_dir:1; unsigned test_only:1; unsigned log:1; unsigned errors:1; unsigned events:1; unsigned is_dir:1; unsigned is_file:1; unsigned is_link:1; unsigned is_exec:1; unsigned is_directio:1; } ngx_open_file_info_t; typedef struct ngx_cached_open_file_s ngx_cached_open_file_t; struct ngx_cached_open_file_s { ngx_rbtree_node_t node; ngx_queue_t queue; u_char *name; time_t created; time_t accessed; ngx_fd_t fd; ngx_file_uniq_t uniq; time_t mtime; off_t size; ngx_err_t err; uint32_t uses; #if (NGX_HAVE_OPENAT) size_t disable_symlinks_from; unsigned disable_symlinks:2; #endif unsigned count:24; unsigned close:1; unsigned use_event:1; unsigned is_dir:1; unsigned is_file:1; unsigned is_link:1; unsigned is_exec:1; unsigned is_directio:1; ngx_event_t *event; }; typedef struct { ngx_rbtree_t rbtree; ngx_rbtree_node_t sentinel; ngx_queue_t expire_queue; ngx_uint_t current; ngx_uint_t max; time_t inactive; } ngx_open_file_cache_t; typedef struct { ngx_open_file_cache_t *cache; ngx_cached_open_file_t *file; ngx_uint_t min_uses; ngx_log_t *log; } ngx_open_file_cache_cleanup_t; typedef struct { /* ngx_connection_t stub to allow use c->fd as event ident */ void *data; ngx_event_t *read; ngx_event_t *write; ngx_fd_t fd; ngx_cached_open_file_t *file; ngx_open_file_cache_t *cache; } ngx_open_file_cache_event_t; ngx_open_file_cache_t *ngx_open_file_cache_init(ngx_pool_t *pool, ngx_uint_t max, time_t inactive); ngx_int_t ngx_open_cached_file(ngx_open_file_cache_t *cache, ngx_str_t *name, ngx_open_file_info_t *of, ngx_pool_t *pool); #endif /* _NGX_OPEN_FILE_CACHE_H_INCLUDED_ */