Mercurial > hg > nginx
view src/http/ngx_http_cache.h @ 5356:acd51b0f6fd4
Disable symlinks: use O_PATH to open path components.
It was introduced in Linux 2.6.39, glibc 2.14 and allows to obtain
file descriptors without actually opening files. Thus made it possible
to traverse path with openat() syscalls without the need to have read
permissions for path components. It is effectively emulates O_SEARCH
which is missing on Linux.
O_PATH is used in combination with O_RDONLY. The last one is ignored
if O_PATH is used, but it allows nginx to not fail when it was built on
modern system (i.e. glibc 2.14+) and run with a kernel older than 2.6.39.
Then O_PATH is unknown to the kernel and ignored, while O_RDONLY is used.
Sadly, fstat() is not working with O_PATH descriptors till Linux 3.6.
As a workaround we fallback to fstatat() with the AT_EMPTY_PATH flag
that was introduced at the same time as O_PATH.
author | Valentin Bartenev <vbart@nginx.com> |
---|---|
date | Mon, 02 Sep 2013 08:07:59 +0400 |
parents | d620f497c50f |
children | 43ccaf8e8728 |
line wrap: on
line source
/* * Copyright (C) Igor Sysoev * Copyright (C) Nginx, Inc. */ #ifndef _NGX_HTTP_CACHE_H_INCLUDED_ #define _NGX_HTTP_CACHE_H_INCLUDED_ #include <ngx_config.h> #include <ngx_core.h> #include <ngx_http.h> #define NGX_HTTP_CACHE_MISS 1 #define NGX_HTTP_CACHE_BYPASS 2 #define NGX_HTTP_CACHE_EXPIRED 3 #define NGX_HTTP_CACHE_STALE 4 #define NGX_HTTP_CACHE_UPDATING 5 #define NGX_HTTP_CACHE_HIT 6 #define NGX_HTTP_CACHE_SCARCE 7 #define NGX_HTTP_CACHE_KEY_LEN 16 typedef struct { ngx_uint_t status; time_t valid; } ngx_http_cache_valid_t; typedef struct { ngx_rbtree_node_t node; ngx_queue_t queue; u_char key[NGX_HTTP_CACHE_KEY_LEN - sizeof(ngx_rbtree_key_t)]; unsigned count:20; unsigned uses:10; unsigned valid_msec:10; unsigned error:10; unsigned exists:1; unsigned updating:1; unsigned deleting:1; /* 11 unused bits */ ngx_file_uniq_t uniq; time_t expire; time_t valid_sec; size_t body_start; off_t fs_size; } ngx_http_file_cache_node_t; struct ngx_http_cache_s { ngx_file_t file; ngx_array_t keys; uint32_t crc32; u_char key[NGX_HTTP_CACHE_KEY_LEN]; ngx_file_uniq_t uniq; time_t valid_sec; time_t last_modified; time_t date; size_t header_start; size_t body_start; off_t length; off_t fs_size; ngx_uint_t min_uses; ngx_uint_t error; ngx_uint_t valid_msec; ngx_buf_t *buf; ngx_http_file_cache_t *file_cache; ngx_http_file_cache_node_t *node; ngx_msec_t lock_timeout; ngx_msec_t wait_time; ngx_event_t wait_event; unsigned lock:1; unsigned waiting:1; unsigned updated:1; unsigned updating:1; unsigned exists:1; unsigned temp_file:1; }; typedef struct { time_t valid_sec; time_t last_modified; time_t date; uint32_t crc32; u_short valid_msec; u_short header_start; u_short body_start; } ngx_http_file_cache_header_t; typedef struct { ngx_rbtree_t rbtree; ngx_rbtree_node_t sentinel; ngx_queue_t queue; ngx_atomic_t cold; ngx_atomic_t loading; off_t size; } ngx_http_file_cache_sh_t; struct ngx_http_file_cache_s { ngx_http_file_cache_sh_t *sh; ngx_slab_pool_t *shpool; ngx_path_t *path; off_t max_size; size_t bsize; time_t inactive; ngx_uint_t files; ngx_uint_t loader_files; ngx_msec_t last; ngx_msec_t loader_sleep; ngx_msec_t loader_threshold; ngx_shm_zone_t *shm_zone; }; ngx_int_t ngx_http_file_cache_new(ngx_http_request_t *r); ngx_int_t ngx_http_file_cache_create(ngx_http_request_t *r); void ngx_http_file_cache_create_key(ngx_http_request_t *r); ngx_int_t ngx_http_file_cache_open(ngx_http_request_t *r); void ngx_http_file_cache_set_header(ngx_http_request_t *r, u_char *buf); void ngx_http_file_cache_update(ngx_http_request_t *r, ngx_temp_file_t *tf); ngx_int_t ngx_http_cache_send(ngx_http_request_t *); void ngx_http_file_cache_free(ngx_http_cache_t *c, ngx_temp_file_t *tf); time_t ngx_http_file_cache_valid(ngx_array_t *cache_valid, ngx_uint_t status); char *ngx_http_file_cache_set_slot(ngx_conf_t *cf, ngx_command_t *cmd, void *conf); char *ngx_http_file_cache_valid_set_slot(ngx_conf_t *cf, ngx_command_t *cmd, void *conf); extern ngx_str_t ngx_http_cache_status[]; #endif /* _NGX_HTTP_CACHE_H_INCLUDED_ */