Too large st_blocks values are now ignored (ticket #157). With XFS, using "allocsize=64m" mount option results in large preallocation being reported in the st_blocks as returned by fstat() till the file is closed. This in turn results in incorrect cache size calculations and wrong clearing based on max_size. To avoid too aggressive cache clearing on such volumes, st_blocks values which result in sizes larger than st_size and eight blocks (an arbitrary limit) are no longer trusted, and we use st_size instead. The ngx_de_fs_size() counterpart is intentionally not modified, as it is used on closed files and hence not affected by this problem.

/*
 * Copyright (C) Igor Sysoev
 * Copyright (C) Nginx, Inc.
 */


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


int
ngx_nonblocking(ngx_socket_t s)
{
    unsigned long  nb = 1;

    return ioctlsocket(s, FIONBIO, &nb);
}


int
ngx_blocking(ngx_socket_t s)
{
    unsigned long  nb = 0;

    return ioctlsocket(s, FIONBIO, &nb);
}


int
ngx_socket_nread(ngx_socket_t s, int *n)
{
    unsigned long  nread;

    if (ioctlsocket(s, FIONREAD, &nread) == -1) {
        return -1;
    }

    *n = nread;

    return 0;
}


int
ngx_tcp_push(ngx_socket_t s)
{
    return 0;
}