Mercurial > hg > nginx
view src/core/ngx_file.h @ 8045:aa28c802409f
Resolver: make TCP write timer event cancelable.
Similar to 70e65bf8dfd7, the change is made to ensure that the ability to
cancel resolver tasks is fully controlled by the caller. As mentioned in the
referenced commit, it is safe to make this timer cancelable because resolve
tasks can have their own timeouts that are not cancelable.
The scenario where this may become a problem is a periodic background resolve
task (not tied to a specific request or a client connection), which receives a
response with short TTL, large enough to warrant fallback to a TCP query.
With each event loop wakeup, we either have a previously set write timer
instance or schedule a new one. The non-cancelable write timer can delay or
block graceful shutdown of a worker even if the ngx_resolver_ctx_t->cancelable
flag is set by the API user, and there are no other tasks or connections.
We use the resolver API in this way to maintain the list of upstream server
addresses specified with the 'resolve' parameter, and there could be third-party
modules implementing similar logic.
author | Aleksei Bavshin <a.bavshin@f5.com> |
---|---|
date | Wed, 01 Jun 2022 20:17:23 -0700 |
parents | 0c572ed91b36 |
children |
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/* * Copyright (C) Igor Sysoev * Copyright (C) Nginx, Inc. */ #ifndef _NGX_FILE_H_INCLUDED_ #define _NGX_FILE_H_INCLUDED_ #include <ngx_config.h> #include <ngx_core.h> struct ngx_file_s { ngx_fd_t fd; ngx_str_t name; ngx_file_info_t info; off_t offset; off_t sys_offset; ngx_log_t *log; #if (NGX_THREADS || NGX_COMPAT) ngx_int_t (*thread_handler)(ngx_thread_task_t *task, ngx_file_t *file); void *thread_ctx; ngx_thread_task_t *thread_task; #endif #if (NGX_HAVE_FILE_AIO || NGX_COMPAT) ngx_event_aio_t *aio; #endif unsigned valid_info:1; unsigned directio:1; }; #define NGX_MAX_PATH_LEVEL 3 typedef ngx_msec_t (*ngx_path_manager_pt) (void *data); typedef ngx_msec_t (*ngx_path_purger_pt) (void *data); typedef void (*ngx_path_loader_pt) (void *data); typedef struct { ngx_str_t name; size_t len; size_t level[NGX_MAX_PATH_LEVEL]; ngx_path_manager_pt manager; ngx_path_purger_pt purger; ngx_path_loader_pt loader; void *data; u_char *conf_file; ngx_uint_t line; } ngx_path_t; typedef struct { ngx_str_t name; size_t level[NGX_MAX_PATH_LEVEL]; } ngx_path_init_t; typedef struct { ngx_file_t file; off_t offset; ngx_path_t *path; ngx_pool_t *pool; char *warn; ngx_uint_t access; unsigned log_level:8; unsigned persistent:1; unsigned clean:1; unsigned thread_write:1; } ngx_temp_file_t; typedef struct { ngx_uint_t access; ngx_uint_t path_access; time_t time; ngx_fd_t fd; unsigned create_path:1; unsigned delete_file:1; ngx_log_t *log; } ngx_ext_rename_file_t; typedef struct { off_t size; size_t buf_size; ngx_uint_t access; time_t time; ngx_log_t *log; } ngx_copy_file_t; typedef struct ngx_tree_ctx_s ngx_tree_ctx_t; typedef ngx_int_t (*ngx_tree_init_handler_pt) (void *ctx, void *prev); typedef ngx_int_t (*ngx_tree_handler_pt) (ngx_tree_ctx_t *ctx, ngx_str_t *name); struct ngx_tree_ctx_s { off_t size; off_t fs_size; ngx_uint_t access; time_t mtime; ngx_tree_init_handler_pt init_handler; ngx_tree_handler_pt file_handler; ngx_tree_handler_pt pre_tree_handler; ngx_tree_handler_pt post_tree_handler; ngx_tree_handler_pt spec_handler; void *data; size_t alloc; ngx_log_t *log; }; ngx_int_t ngx_get_full_name(ngx_pool_t *pool, ngx_str_t *prefix, ngx_str_t *name); ssize_t ngx_write_chain_to_temp_file(ngx_temp_file_t *tf, ngx_chain_t *chain); ngx_int_t ngx_create_temp_file(ngx_file_t *file, ngx_path_t *path, ngx_pool_t *pool, ngx_uint_t persistent, ngx_uint_t clean, ngx_uint_t access); void ngx_create_hashed_filename(ngx_path_t *path, u_char *file, size_t len); ngx_int_t ngx_create_path(ngx_file_t *file, ngx_path_t *path); ngx_err_t ngx_create_full_path(u_char *dir, ngx_uint_t access); ngx_int_t ngx_add_path(ngx_conf_t *cf, ngx_path_t **slot); ngx_int_t ngx_create_paths(ngx_cycle_t *cycle, ngx_uid_t user); ngx_int_t ngx_ext_rename_file(ngx_str_t *src, ngx_str_t *to, ngx_ext_rename_file_t *ext); ngx_int_t ngx_copy_file(u_char *from, u_char *to, ngx_copy_file_t *cf); ngx_int_t ngx_walk_tree(ngx_tree_ctx_t *ctx, ngx_str_t *tree); ngx_atomic_uint_t ngx_next_temp_number(ngx_uint_t collision); char *ngx_conf_set_path_slot(ngx_conf_t *cf, ngx_command_t *cmd, void *conf); char *ngx_conf_merge_path_value(ngx_conf_t *cf, ngx_path_t **path, ngx_path_t *prev, ngx_path_init_t *init); char *ngx_conf_set_access_slot(ngx_conf_t *cf, ngx_command_t *cmd, void *conf); extern ngx_atomic_t *ngx_temp_number; extern ngx_atomic_int_t ngx_random_number; #endif /* _NGX_FILE_H_INCLUDED_ */