view src/os/unix/ngx_send.c @ 9306:e46e1ea89ccd default tip

Upstream: $upstream_cache_age variable. The variable reflects response age, including the time spent in the cache and the upstream response age as obtained from the "Age" header. If the response wasn't cached, the variable reflects the "Age" header of the upstream response. If the intended use case is to cache responses as per HTTP/1.1 caching model, the $upstream_cache_age variable can be used to provide the "Age" header with the "add_header" directive, such as: add_header Age $upstream_cache_age; This now removes the "Age" header if it was present. Further, the "expires" directives now removes the "Age" header if it was present in the response, as the "expires" directive assumes zero age when it adds "Expires" and "Cache-Control" headers.
author Maxim Dounin <mdounin@mdounin.ru>
date Thu, 18 Jul 2024 19:39:45 +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;
        }
    }
}