Mercurial > hg > nginx
view src/core/ngx_regex.c @ 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 | 640288d0e1bc |
children | f684178faec9 |
line wrap: on
line source
/* * Copyright (C) Igor Sysoev * Copyright (C) Nginx, Inc. */ #include <ngx_config.h> #include <ngx_core.h> typedef struct { ngx_flag_t pcre_jit; } ngx_regex_conf_t; static void * ngx_libc_cdecl ngx_regex_malloc(size_t size); static void ngx_libc_cdecl ngx_regex_free(void *p); #if (NGX_HAVE_PCRE_JIT) static void ngx_pcre_free_studies(void *data); #endif static ngx_int_t ngx_regex_module_init(ngx_cycle_t *cycle); static void *ngx_regex_create_conf(ngx_cycle_t *cycle); static char *ngx_regex_init_conf(ngx_cycle_t *cycle, void *conf); static char *ngx_regex_pcre_jit(ngx_conf_t *cf, void *post, void *data); static ngx_conf_post_t ngx_regex_pcre_jit_post = { ngx_regex_pcre_jit }; static ngx_command_t ngx_regex_commands[] = { { ngx_string("pcre_jit"), NGX_MAIN_CONF|NGX_DIRECT_CONF|NGX_CONF_FLAG, ngx_conf_set_flag_slot, 0, offsetof(ngx_regex_conf_t, pcre_jit), &ngx_regex_pcre_jit_post }, ngx_null_command }; static ngx_core_module_t ngx_regex_module_ctx = { ngx_string("regex"), ngx_regex_create_conf, ngx_regex_init_conf }; ngx_module_t ngx_regex_module = { NGX_MODULE_V1, &ngx_regex_module_ctx, /* module context */ ngx_regex_commands, /* module directives */ NGX_CORE_MODULE, /* module type */ NULL, /* init master */ ngx_regex_module_init, /* init module */ NULL, /* init process */ NULL, /* init thread */ NULL, /* exit thread */ NULL, /* exit process */ NULL, /* exit master */ NGX_MODULE_V1_PADDING }; static ngx_pool_t *ngx_pcre_pool; static ngx_list_t *ngx_pcre_studies; void ngx_regex_init(void) { pcre_malloc = ngx_regex_malloc; pcre_free = ngx_regex_free; } static ngx_inline void ngx_regex_malloc_init(ngx_pool_t *pool) { ngx_pcre_pool = pool; } static ngx_inline void ngx_regex_malloc_done(void) { ngx_pcre_pool = NULL; } ngx_int_t ngx_regex_compile(ngx_regex_compile_t *rc) { int n, erroff; char *p; pcre *re; const char *errstr; ngx_regex_elt_t *elt; ngx_regex_malloc_init(rc->pool); re = pcre_compile((const char *) rc->pattern.data, (int) rc->options, &errstr, &erroff, NULL); /* ensure that there is no current pool */ ngx_regex_malloc_done(); if (re == NULL) { if ((size_t) erroff == rc->pattern.len) { rc->err.len = ngx_snprintf(rc->err.data, rc->err.len, "pcre_compile() failed: %s in \"%V\"", errstr, &rc->pattern) - rc->err.data; } else { rc->err.len = ngx_snprintf(rc->err.data, rc->err.len, "pcre_compile() failed: %s in \"%V\" at \"%s\"", errstr, &rc->pattern, rc->pattern.data + erroff) - rc->err.data; } return NGX_ERROR; } rc->regex = ngx_pcalloc(rc->pool, sizeof(ngx_regex_t)); if (rc->regex == NULL) { goto nomem; } rc->regex->code = re; /* do not study at runtime */ if (ngx_pcre_studies != NULL) { elt = ngx_list_push(ngx_pcre_studies); if (elt == NULL) { goto nomem; } elt->regex = rc->regex; elt->name = rc->pattern.data; } n = pcre_fullinfo(re, NULL, PCRE_INFO_CAPTURECOUNT, &rc->captures); if (n < 0) { p = "pcre_fullinfo(\"%V\", PCRE_INFO_CAPTURECOUNT) failed: %d"; goto failed; } if (rc->captures == 0) { return NGX_OK; } n = pcre_fullinfo(re, NULL, PCRE_INFO_NAMECOUNT, &rc->named_captures); if (n < 0) { p = "pcre_fullinfo(\"%V\", PCRE_INFO_NAMECOUNT) failed: %d"; goto failed; } if (rc->named_captures == 0) { return NGX_OK; } n = pcre_fullinfo(re, NULL, PCRE_INFO_NAMEENTRYSIZE, &rc->name_size); if (n < 0) { p = "pcre_fullinfo(\"%V\", PCRE_INFO_NAMEENTRYSIZE) failed: %d"; goto failed; } n = pcre_fullinfo(re, NULL, PCRE_INFO_NAMETABLE, &rc->names); if (n < 0) { p = "pcre_fullinfo(\"%V\", PCRE_INFO_NAMETABLE) failed: %d"; goto failed; } return NGX_OK; failed: rc->err.len = ngx_snprintf(rc->err.data, rc->err.len, p, &rc->pattern, n) - rc->err.data; return NGX_ERROR; nomem: rc->err.len = ngx_snprintf(rc->err.data, rc->err.len, "regex \"%V\" compilation failed: no memory", &rc->pattern) - rc->err.data; return NGX_ERROR; } ngx_int_t ngx_regex_exec_array(ngx_array_t *a, ngx_str_t *s, ngx_log_t *log) { ngx_int_t n; ngx_uint_t i; ngx_regex_elt_t *re; re = a->elts; for (i = 0; i < a->nelts; i++) { n = ngx_regex_exec(re[i].regex, s, NULL, 0); if (n == NGX_REGEX_NO_MATCHED) { continue; } if (n < 0) { ngx_log_error(NGX_LOG_ALERT, log, 0, ngx_regex_exec_n " failed: %i on \"%V\" using \"%s\"", n, s, re[i].name); return NGX_ERROR; } /* match */ return NGX_OK; } return NGX_DECLINED; } static void * ngx_libc_cdecl ngx_regex_malloc(size_t size) { ngx_pool_t *pool; pool = ngx_pcre_pool; if (pool) { return ngx_palloc(pool, size); } return NULL; } static void ngx_libc_cdecl ngx_regex_free(void *p) { return; } #if (NGX_HAVE_PCRE_JIT) static void ngx_pcre_free_studies(void *data) { ngx_list_t *studies = data; ngx_uint_t i; ngx_list_part_t *part; ngx_regex_elt_t *elts; part = &studies->part; elts = part->elts; for (i = 0 ; /* void */ ; i++) { if (i >= part->nelts) { if (part->next == NULL) { break; } part = part->next; elts = part->elts; i = 0; } if (elts[i].regex->extra != NULL) { pcre_free_study(elts[i].regex->extra); } } } #endif static ngx_int_t ngx_regex_module_init(ngx_cycle_t *cycle) { int opt; const char *errstr; ngx_uint_t i; ngx_list_part_t *part; ngx_regex_elt_t *elts; opt = 0; #if (NGX_HAVE_PCRE_JIT) { ngx_regex_conf_t *rcf; ngx_pool_cleanup_t *cln; rcf = (ngx_regex_conf_t *) ngx_get_conf(cycle->conf_ctx, ngx_regex_module); if (rcf->pcre_jit) { opt = PCRE_STUDY_JIT_COMPILE; /* * The PCRE JIT compiler uses mmap for its executable codes, so we * have to explicitly call the pcre_free_study() function to free * this memory. */ cln = ngx_pool_cleanup_add(cycle->pool, 0); if (cln == NULL) { return NGX_ERROR; } cln->handler = ngx_pcre_free_studies; cln->data = ngx_pcre_studies; } } #endif ngx_regex_malloc_init(cycle->pool); part = &ngx_pcre_studies->part; elts = part->elts; for (i = 0 ; /* void */ ; i++) { if (i >= part->nelts) { if (part->next == NULL) { break; } part = part->next; elts = part->elts; i = 0; } elts[i].regex->extra = pcre_study(elts[i].regex->code, opt, &errstr); if (errstr != NULL) { ngx_log_error(NGX_LOG_ALERT, cycle->log, 0, "pcre_study() failed: %s in \"%s\"", errstr, elts[i].name); } #if (NGX_HAVE_PCRE_JIT) if (opt & PCRE_STUDY_JIT_COMPILE) { int jit, n; jit = 0; n = pcre_fullinfo(elts[i].regex->code, elts[i].regex->extra, PCRE_INFO_JIT, &jit); if (n != 0 || jit != 1) { ngx_log_error(NGX_LOG_INFO, cycle->log, 0, "JIT compiler does not support pattern: \"%s\"", elts[i].name); } } #endif } ngx_regex_malloc_done(); ngx_pcre_studies = NULL; return NGX_OK; } static void * ngx_regex_create_conf(ngx_cycle_t *cycle) { ngx_regex_conf_t *rcf; rcf = ngx_pcalloc(cycle->pool, sizeof(ngx_regex_conf_t)); if (rcf == NULL) { return NULL; } rcf->pcre_jit = NGX_CONF_UNSET; ngx_pcre_studies = ngx_list_create(cycle->pool, 8, sizeof(ngx_regex_elt_t)); if (ngx_pcre_studies == NULL) { return NULL; } return rcf; } static char * ngx_regex_init_conf(ngx_cycle_t *cycle, void *conf) { ngx_regex_conf_t *rcf = conf; ngx_conf_init_value(rcf->pcre_jit, 0); return NGX_CONF_OK; } static char * ngx_regex_pcre_jit(ngx_conf_t *cf, void *post, void *data) { ngx_flag_t *fp = data; if (*fp == 0) { return NGX_CONF_OK; } #if (NGX_HAVE_PCRE_JIT) { int jit, r; jit = 0; r = pcre_config(PCRE_CONFIG_JIT, &jit); if (r != 0 || jit != 1) { ngx_conf_log_error(NGX_LOG_WARN, cf, 0, "PCRE library does not support JIT"); *fp = 0; } } #else ngx_conf_log_error(NGX_LOG_WARN, cf, 0, "nginx was built without PCRE JIT support"); *fp = 0; #endif return NGX_CONF_OK; }