view src/os/unix/ngx_socket.c @ 5992:174512857ccf

Cache: do not inherit last_modified and etag from stale response. When replacing a stale cache entry, its last_modified and etag could be inherited from the old entry if the response code is not 200 or 206. Moreover, etag could be inherited with any response code if it's missing in the new response. As a result, the cache entry is left with invalid last_modified or etag which could lead to broken revalidation. For example, when a file is deleted from backend, its last_modified is copied to the new 404 cache entry and is used later for revalidation. Once the old file appears again with its original timestamp, revalidation succeeds and the cached 404 response is sent to client instead of the file. The problem appeared with etags in 44b9ab7752e3 (1.7.3) and affected last_modified in 1573fc7875fa (1.7.9).
author Roman Arutyunyan <arut@nginx.com>
date Mon, 02 Mar 2015 19:47:13 +0300
parents d620f497c50f
children
line wrap: on
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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