view src/os/unix/ngx_udp_send.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 8f038068f4bc
children
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/*
 * Copyright (C) Igor Sysoev
 * Copyright (C) Nginx, Inc.
 */


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


ssize_t
ngx_udp_unix_send(ngx_connection_t *c, u_char *buf, size_t size)
{
    ssize_t       n;
    ngx_err_t     err;
    ngx_event_t  *wev;

    wev = c->write;

    for ( ;; ) {
        n = sendto(c->fd, buf, size, 0, c->sockaddr, c->socklen);

        ngx_log_debug4(NGX_LOG_DEBUG_EVENT, c->log, 0,
                       "sendto: fd:%d %z of %uz to \"%V\"",
                       c->fd, n, size, &c->addr_text);

        if (n >= 0) {
            if ((size_t) n != size) {
                wev->error = 1;
                (void) ngx_connection_error(c, 0, "sendto() incomplete");
                return NGX_ERROR;
            }

            c->sent += n;

            return n;
        }

        err = ngx_socket_errno;

        if (err == NGX_EAGAIN) {
            wev->ready = 0;
            ngx_log_debug0(NGX_LOG_DEBUG_EVENT, c->log, NGX_EAGAIN,
                           "sendto() not ready");
            return NGX_AGAIN;
        }

        if (err != NGX_EINTR) {
            wev->error = 1;
            (void) ngx_connection_error(c, err, "sendto() failed");
            return NGX_ERROR;
        }
    }
}