view src/os/unix/ngx_send.c @ 8058:f3510cb959d1

Events: fixed EPOLLRDHUP with FIONREAD (ticket #2367). When reading exactly rev->available bytes, rev->available might become 0 after FIONREAD usage introduction in efd71d49bde0. On the next call of ngx_readv_chain() on systems with EPOLLRDHUP this resulted in return without any actions, that is, with rev->ready set, and this in turn resulted in no timers set in event pipe, leading to socket leaks. Fix is to reset rev->ready in ngx_readv_chain() when returning due to rev->available being 0 with EPOLLRDHUP, much like it is already done in ngx_unix_recv(). This ensures that if rev->available will become 0, on systems with EPOLLRDHUP support appropriate EPOLLRDHUP-specific handling will happen on the next ngx_readv_chain() call. While here, also synced ngx_readv_chain() to match ngx_unix_recv() and reset rev->ready when returning due to rev->available being 0 with kqueue. This is mostly cosmetic change, as rev->ready is anyway reset when rev->available is set to 0.
author Maxim Dounin <mdounin@mdounin.ru>
date Fri, 15 Jul 2022 15:19:32 +0300
parents f01ab2dbcfdc
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_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;

#if (NGX_HAVE_KQUEUE)

    if ((ngx_event_flags & NGX_USE_KQUEUE_EVENT) && wev->pending_eof) {
        (void) ngx_connection_error(c, wev->kq_errno,
                               "kevent() reported about an closed connection");
        wev->error = 1;
        return NGX_ERROR;
    }

#endif

    for ( ;; ) {
        n = send(c->fd, buf, size, 0);

        ngx_log_debug3(NGX_LOG_DEBUG_EVENT, c->log, 0,
                       "send: fd:%d %z of %uz", c->fd, n, size);

        if (n > 0) {
            if (n < (ssize_t) size) {
                wev->ready = 0;
            }

            c->sent += n;

            return n;
        }

        err = ngx_socket_errno;

        if (n == 0) {
            ngx_log_error(NGX_LOG_ALERT, c->log, err, "send() returned zero");
            wev->ready = 0;
            return n;
        }

        if (err == NGX_EAGAIN || err == NGX_EINTR) {
            wev->ready = 0;

            ngx_log_debug0(NGX_LOG_DEBUG_EVENT, c->log, err,
                           "send() not ready");

            if (err == NGX_EAGAIN) {
                return NGX_AGAIN;
            }

        } else {
            wev->error = 1;
            (void) ngx_connection_error(c, err, "send() failed");
            return NGX_ERROR;
        }
    }
}