view src/core/ngx_times.h @ 8018:5119c8150478

Fixed runtime handling of systems without EPOLLRDHUP support. In 7583:efd71d49bde0 (nginx 1.17.5) along with introduction of the ioctl(FIONREAD) support proper handling of systems without EPOLLRDHUP support in the kernel (but with EPOLLRDHUP in headers) was broken. Before the change, rev->available was never set to 0 unless ngx_use_epoll_rdhup was also set (that is, runtime test for EPOLLRDHUP introduced in 6536:f7849bfb6d21 succeeded). After the change, rev->available might reach 0 on systems without runtime EPOLLRDHUP support, stopping further reading in ngx_readv_chain() and ngx_unix_recv(). And, if EOF happened to be already reported along with the last event, it is not reported again by epoll_wait(), leading to connection hangs and timeouts on such systems. This affects Linux kernels before 2.6.17 if nginx was compiled with newer headers, and, more importantly, emulation layers, such as DigitalOcean's App Platform's / gVisor's epoll emulation layer. Fix is to explicitly check ngx_use_epoll_rdhup before the corresponding rev->pending_eof tests in ngx_readv_chain() and ngx_unix_recv().
author Marcus Ball <marcus.ball@live.com>
date Mon, 30 May 2022 02:38:07 +0300
parents 76e7e20cda05
children
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/*
 * Copyright (C) Igor Sysoev
 * Copyright (C) Nginx, Inc.
 */


#ifndef _NGX_TIMES_H_INCLUDED_
#define _NGX_TIMES_H_INCLUDED_


#include <ngx_config.h>
#include <ngx_core.h>


typedef struct {
    time_t      sec;
    ngx_uint_t  msec;
    ngx_int_t   gmtoff;
} ngx_time_t;


void ngx_time_init(void);
void ngx_time_update(void);
void ngx_time_sigsafe_update(void);
u_char *ngx_http_time(u_char *buf, time_t t);
u_char *ngx_http_cookie_time(u_char *buf, time_t t);
void ngx_gmtime(time_t t, ngx_tm_t *tp);

time_t ngx_next_time(time_t when);
#define ngx_next_time_n      "mktime()"


extern volatile ngx_time_t  *ngx_cached_time;

#define ngx_time()           ngx_cached_time->sec
#define ngx_timeofday()      (ngx_time_t *) ngx_cached_time

extern volatile ngx_str_t    ngx_cached_err_log_time;
extern volatile ngx_str_t    ngx_cached_http_time;
extern volatile ngx_str_t    ngx_cached_http_log_time;
extern volatile ngx_str_t    ngx_cached_http_log_iso8601;
extern volatile ngx_str_t    ngx_cached_syslog_time;

/*
 * milliseconds elapsed since some unspecified point in the past
 * and truncated to ngx_msec_t, used in event timers
 */
extern volatile ngx_msec_t  ngx_current_msec;


#endif /* _NGX_TIMES_H_INCLUDED_ */