view src/os/unix/ngx_posix_init.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 16013b71feed
children cb31017e961b
line wrap: on
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/*
 * Copyright (C) Igor Sysoev
 * Copyright (C) Nginx, Inc.
 */


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


ngx_int_t   ngx_ncpu;
ngx_int_t   ngx_max_sockets;
ngx_uint_t  ngx_inherited_nonblocking;
ngx_uint_t  ngx_tcp_nodelay_and_tcp_nopush;


struct rlimit  rlmt;


ngx_os_io_t ngx_os_io = {
    ngx_unix_recv,
    ngx_readv_chain,
    ngx_udp_unix_recv,
    ngx_unix_send,
    ngx_writev_chain,
    0
};


ngx_int_t
ngx_os_init(ngx_log_t *log)
{
    ngx_uint_t  n;

#if (NGX_HAVE_OS_SPECIFIC_INIT)
    if (ngx_os_specific_init(log) != NGX_OK) {
        return NGX_ERROR;
    }
#endif

    if (ngx_init_setproctitle(log) != NGX_OK) {
        return NGX_ERROR;
    }

    ngx_pagesize = getpagesize();
    ngx_cacheline_size = NGX_CPU_CACHE_LINE;

    for (n = ngx_pagesize; n >>= 1; ngx_pagesize_shift++) { /* void */ }

#if (NGX_HAVE_SC_NPROCESSORS_ONLN)
    if (ngx_ncpu == 0) {
        ngx_ncpu = sysconf(_SC_NPROCESSORS_ONLN);
    }
#endif

    if (ngx_ncpu < 1) {
        ngx_ncpu = 1;
    }

    ngx_cpuinfo();

    if (getrlimit(RLIMIT_NOFILE, &rlmt) == -1) {
        ngx_log_error(NGX_LOG_ALERT, log, errno,
                      "getrlimit(RLIMIT_NOFILE) failed)");
        return NGX_ERROR;
    }

    ngx_max_sockets = (ngx_int_t) rlmt.rlim_cur;

#if (NGX_HAVE_INHERITED_NONBLOCK || NGX_HAVE_ACCEPT4)
    ngx_inherited_nonblocking = 1;
#else
    ngx_inherited_nonblocking = 0;
#endif

    srandom(ngx_time());

    return NGX_OK;
}


void
ngx_os_status(ngx_log_t *log)
{
    ngx_log_error(NGX_LOG_NOTICE, log, 0, NGINX_VER_BUILD);

#ifdef NGX_COMPILER
    ngx_log_error(NGX_LOG_NOTICE, log, 0, "built by " NGX_COMPILER);
#endif

#if (NGX_HAVE_OS_SPECIFIC_INIT)
    ngx_os_specific_status(log);
#endif

    ngx_log_error(NGX_LOG_NOTICE, log, 0,
                  "getrlimit(RLIMIT_NOFILE): %r:%r",
                  rlmt.rlim_cur, rlmt.rlim_max);
}


#if 0

ngx_int_t
ngx_posix_post_conf_init(ngx_log_t *log)
{
    ngx_fd_t  pp[2];

    if (pipe(pp) == -1) {
        ngx_log_error(NGX_LOG_EMERG, log, ngx_errno, "pipe() failed");
        return NGX_ERROR;
    }

    if (dup2(pp[1], STDERR_FILENO) == -1) {
        ngx_log_error(NGX_LOG_EMERG, log, errno, "dup2(STDERR) failed");
        return NGX_ERROR;
    }

    if (pp[1] > STDERR_FILENO) {
        if (close(pp[1]) == -1) {
            ngx_log_error(NGX_LOG_EMERG, log, errno, "close() failed");
            return NGX_ERROR;
        }
    }

    return NGX_OK;
}

#endif