view src/event/ngx_event_connect.h @ 7584:9d2ad2fb4423

SSL: available bytes handling (ticket #1431). Added code to track number of bytes available in the socket. This makes it possible to avoid looping for a long time while working with fast enough peer when data are added to the socket buffer faster than we are able to read and process data. When kernel does not provide number of bytes available, it is retrieved using ioctl(FIONREAD) as long as a buffer is filled by SSL_read(). It is assumed that number of bytes returned by SSL_read() is close to the number of bytes read from the socket, as we do not use SSL compression. But even if it is not true for some reason, this is not important, as we post an additional reading event anyway. Note that data can be buffered at SSL layer, and it is not possible to simply stop reading at some point and wait till the event will be reported by the kernel again. This can be only done when there are no data in SSL buffers, and there is no good way to find out if it's the case. Instead of trying to figure out if SSL buffers are empty, this patch introduces events posted for the next event loop iteration - such events will be processed only on the next event loop iteration, after going into the kernel and retrieving additional events. This seems to be simple and reliable approach.
author Maxim Dounin <mdounin@mdounin.ru>
date Thu, 17 Oct 2019 16:02:24 +0300
parents 570d8c626eea
children
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/*
 * Copyright (C) Igor Sysoev
 * Copyright (C) Nginx, Inc.
 */


#ifndef _NGX_EVENT_CONNECT_H_INCLUDED_
#define _NGX_EVENT_CONNECT_H_INCLUDED_


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


#define NGX_PEER_KEEPALIVE           1
#define NGX_PEER_NEXT                2
#define NGX_PEER_FAILED              4


typedef struct ngx_peer_connection_s  ngx_peer_connection_t;

typedef ngx_int_t (*ngx_event_get_peer_pt)(ngx_peer_connection_t *pc,
    void *data);
typedef void (*ngx_event_free_peer_pt)(ngx_peer_connection_t *pc, void *data,
    ngx_uint_t state);
typedef void (*ngx_event_notify_peer_pt)(ngx_peer_connection_t *pc,
    void *data, ngx_uint_t type);
typedef ngx_int_t (*ngx_event_set_peer_session_pt)(ngx_peer_connection_t *pc,
    void *data);
typedef void (*ngx_event_save_peer_session_pt)(ngx_peer_connection_t *pc,
    void *data);


struct ngx_peer_connection_s {
    ngx_connection_t                *connection;

    struct sockaddr                 *sockaddr;
    socklen_t                        socklen;
    ngx_str_t                       *name;

    ngx_uint_t                       tries;
    ngx_msec_t                       start_time;

    ngx_event_get_peer_pt            get;
    ngx_event_free_peer_pt           free;
    ngx_event_notify_peer_pt         notify;
    void                            *data;

#if (NGX_SSL || NGX_COMPAT)
    ngx_event_set_peer_session_pt    set_session;
    ngx_event_save_peer_session_pt   save_session;
#endif

    ngx_addr_t                      *local;

    int                              type;
    int                              rcvbuf;

    ngx_log_t                       *log;

    unsigned                         cached:1;
    unsigned                         transparent:1;
    unsigned                         so_keepalive:1;
    unsigned                         down:1;

                                     /* ngx_connection_log_error_e */
    unsigned                         log_error:2;

    NGX_COMPAT_BEGIN(2)
    NGX_COMPAT_END
};


ngx_int_t ngx_event_connect_peer(ngx_peer_connection_t *pc);
ngx_int_t ngx_event_get_peer(ngx_peer_connection_t *pc, void *data);


#endif /* _NGX_EVENT_CONNECT_H_INCLUDED_ */