view src/os/unix/ngx_process.h @ 7142:b9d919b53593 stable-1.12

Stream: relaxed next upstream condition (ticket #1317). When switching to a next upstream, some buffers could be stuck in the middle of the filter chain. A condition existed that raised an error when this happened. As it turned out, this condition prevented switching to a next upstream if ssl preread was used with the TCP protocol (see the ticket). In fact, the condition does not make sense for TCP, since after successful connection to an upstream switching to another upstream never happens. As for UDP, the issue with stuck buffers is unlikely to happen, but is still possible. Specifically, if a filter delays sending data to upstream. The condition can be relaxed to only check the "buffered" bitmask of the upstream connection. The new condition is simpler and fixes the ticket issue as well. Additionally, the upstream_out chain is now reset for UDP prior to connecting to a new upstream to prevent repeating the client data twice.
author Roman Arutyunyan <arut@nginx.com>
date Mon, 11 Sep 2017 15:32:31 +0300
parents f31162fefe01
children 8b84d60ef13d
line wrap: on
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/*
 * Copyright (C) Igor Sysoev
 * Copyright (C) Nginx, Inc.
 */


#ifndef _NGX_PROCESS_H_INCLUDED_
#define _NGX_PROCESS_H_INCLUDED_


#include <ngx_setaffinity.h>
#include <ngx_setproctitle.h>


typedef pid_t       ngx_pid_t;

#define NGX_INVALID_PID  -1

typedef void (*ngx_spawn_proc_pt) (ngx_cycle_t *cycle, void *data);

typedef struct {
    ngx_pid_t           pid;
    int                 status;
    ngx_socket_t        channel[2];

    ngx_spawn_proc_pt   proc;
    void               *data;
    char               *name;

    unsigned            respawn:1;
    unsigned            just_spawn:1;
    unsigned            detached:1;
    unsigned            exiting:1;
    unsigned            exited:1;
} ngx_process_t;


typedef struct {
    char         *path;
    char         *name;
    char *const  *argv;
    char *const  *envp;
} ngx_exec_ctx_t;


#define NGX_MAX_PROCESSES         1024

#define NGX_PROCESS_NORESPAWN     -1
#define NGX_PROCESS_JUST_SPAWN    -2
#define NGX_PROCESS_RESPAWN       -3
#define NGX_PROCESS_JUST_RESPAWN  -4
#define NGX_PROCESS_DETACHED      -5


#define ngx_getpid   getpid

#ifndef ngx_log_pid
#define ngx_log_pid  ngx_pid
#endif


ngx_pid_t ngx_spawn_process(ngx_cycle_t *cycle,
    ngx_spawn_proc_pt proc, void *data, char *name, ngx_int_t respawn);
ngx_pid_t ngx_execute(ngx_cycle_t *cycle, ngx_exec_ctx_t *ctx);
ngx_int_t ngx_init_signals(ngx_log_t *log);
void ngx_debug_point(void);


#if (NGX_HAVE_SCHED_YIELD)
#define ngx_sched_yield()  sched_yield()
#else
#define ngx_sched_yield()  usleep(1)
#endif


extern int            ngx_argc;
extern char         **ngx_argv;
extern char         **ngx_os_argv;

extern ngx_pid_t      ngx_pid;
extern ngx_socket_t   ngx_channel;
extern ngx_int_t      ngx_process_slot;
extern ngx_int_t      ngx_last_process;
extern ngx_process_t  ngx_processes[NGX_MAX_PROCESSES];


#endif /* _NGX_PROCESS_H_INCLUDED_ */