view src/os/unix/ngx_socket.c @ 7870:e169cce912c7 quic

Avoid retransmitting of packets with discarded keys. Sections 4.10.1 and 4.10.2 of quic transport describe discarding of initial and handshake keys. Since the keys are discarded, we no longer need to retransmit packets and corresponding queues should be emptied. This patch removes previously added workaround that did not require acknowledgement for initial packets, resulting in avoiding retransmission, which is wrong because a packet could be lost and we have to retransmit it.
author Vladimir Homutov <vl@nginx.com>
date Mon, 18 May 2020 13:54:53 +0300
parents d620f497c50f
children
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/*
 * Copyright (C) Igor Sysoev
 * Copyright (C) Nginx, Inc.
 */


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


/*
 * ioctl(FIONBIO) sets a non-blocking mode with the single syscall
 * while fcntl(F_SETFL, O_NONBLOCK) needs to learn the current state
 * using fcntl(F_GETFL).
 *
 * ioctl() and fcntl() are syscalls at least in FreeBSD 2.x, Linux 2.2
 * and Solaris 7.
 *
 * ioctl() in Linux 2.4 and 2.6 uses BKL, however, fcntl(F_SETFL) uses it too.
 */


#if (NGX_HAVE_FIONBIO)

int
ngx_nonblocking(ngx_socket_t s)
{
    int  nb;

    nb = 1;

    return ioctl(s, FIONBIO, &nb);
}


int
ngx_blocking(ngx_socket_t s)
{
    int  nb;

    nb = 0;

    return ioctl(s, FIONBIO, &nb);
}

#endif


#if (NGX_FREEBSD)

int
ngx_tcp_nopush(ngx_socket_t s)
{
    int  tcp_nopush;

    tcp_nopush = 1;

    return setsockopt(s, IPPROTO_TCP, TCP_NOPUSH,
                      (const void *) &tcp_nopush, sizeof(int));
}


int
ngx_tcp_push(ngx_socket_t s)
{
    int  tcp_nopush;

    tcp_nopush = 0;

    return setsockopt(s, IPPROTO_TCP, TCP_NOPUSH,
                      (const void *) &tcp_nopush, sizeof(int));
}

#elif (NGX_LINUX)


int
ngx_tcp_nopush(ngx_socket_t s)
{
    int  cork;

    cork = 1;

    return setsockopt(s, IPPROTO_TCP, TCP_CORK,
                      (const void *) &cork, sizeof(int));
}


int
ngx_tcp_push(ngx_socket_t s)
{
    int  cork;

    cork = 0;

    return setsockopt(s, IPPROTO_TCP, TCP_CORK,
                      (const void *) &cork, sizeof(int));
}

#else

int
ngx_tcp_nopush(ngx_socket_t s)
{
    return 0;
}


int
ngx_tcp_push(ngx_socket_t s)
{
    return 0;
}

#endif