Mercurial > hg > nginx
view src/misc/ngx_google_perftools_module.c @ 5992:174512857ccf
Cache: do not inherit last_modified and etag from stale response.
When replacing a stale cache entry, its last_modified and etag could be
inherited from the old entry if the response code is not 200 or 206. Moreover,
etag could be inherited with any response code if it's missing in the new
response. As a result, the cache entry is left with invalid last_modified or
etag which could lead to broken revalidation.
For example, when a file is deleted from backend, its last_modified is copied to
the new 404 cache entry and is used later for revalidation. Once the old file
appears again with its original timestamp, revalidation succeeds and the cached
404 response is sent to client instead of the file.
The problem appeared with etags in 44b9ab7752e3 (1.7.3) and affected
last_modified in 1573fc7875fa (1.7.9).
author | Roman Arutyunyan <arut@nginx.com> |
---|---|
date | Mon, 02 Mar 2015 19:47:13 +0300 |
parents | d620f497c50f |
children | a27e0c7e198c |
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/* * Copyright (C) Igor Sysoev * Copyright (C) Nginx, Inc. */ #include <ngx_config.h> #include <ngx_core.h> /* * declare Profiler interface here because * <google/profiler.h> is C++ header file */ int ProfilerStart(u_char* fname); void ProfilerStop(void); void ProfilerRegisterThread(void); static void *ngx_google_perftools_create_conf(ngx_cycle_t *cycle); static ngx_int_t ngx_google_perftools_worker(ngx_cycle_t *cycle); typedef struct { ngx_str_t profiles; } ngx_google_perftools_conf_t; static ngx_command_t ngx_google_perftools_commands[] = { { ngx_string("google_perftools_profiles"), NGX_MAIN_CONF|NGX_DIRECT_CONF|NGX_CONF_TAKE1, ngx_conf_set_str_slot, 0, offsetof(ngx_google_perftools_conf_t, profiles), NULL }, ngx_null_command }; static ngx_core_module_t ngx_google_perftools_module_ctx = { ngx_string("google_perftools"), ngx_google_perftools_create_conf, NULL }; ngx_module_t ngx_google_perftools_module = { NGX_MODULE_V1, &ngx_google_perftools_module_ctx, /* module context */ ngx_google_perftools_commands, /* module directives */ NGX_CORE_MODULE, /* module type */ NULL, /* init master */ NULL, /* init module */ ngx_google_perftools_worker, /* init process */ NULL, /* init thread */ NULL, /* exit thread */ NULL, /* exit process */ NULL, /* exit master */ NGX_MODULE_V1_PADDING }; static void * ngx_google_perftools_create_conf(ngx_cycle_t *cycle) { ngx_google_perftools_conf_t *gptcf; gptcf = ngx_pcalloc(cycle->pool, sizeof(ngx_google_perftools_conf_t)); if (gptcf == NULL) { return NULL; } /* * set by ngx_pcalloc() * * gptcf->profiles = { 0, NULL }; */ return gptcf; } static ngx_int_t ngx_google_perftools_worker(ngx_cycle_t *cycle) { u_char *profile; ngx_google_perftools_conf_t *gptcf; gptcf = (ngx_google_perftools_conf_t *) ngx_get_conf(cycle->conf_ctx, ngx_google_perftools_module); if (gptcf->profiles.len == 0) { return NGX_OK; } profile = ngx_alloc(gptcf->profiles.len + NGX_INT_T_LEN + 2, cycle->log); if (profile == NULL) { return NGX_OK; } if (getenv("CPUPROFILE")) { /* disable inherited Profiler enabled in master process */ ProfilerStop(); } ngx_sprintf(profile, "%V.%d%Z", &gptcf->profiles, ngx_pid); if (ProfilerStart(profile)) { /* start ITIMER_PROF timer */ ProfilerRegisterThread(); } else { ngx_log_error(NGX_LOG_CRIT, cycle->log, ngx_errno, "ProfilerStart(%s) failed", profile); } ngx_free(profile); return NGX_OK; } /* ProfilerStop() is called on Profiler destruction */