view src/os/unix/ngx_linux_init.c @ 3440:88741ec7731a stable-0.7

merge r3294, r3305: Fix a bug introduced in r2032: After a child process has read a terminate message from a channel, the process tries to read the channel again. The kernel (at least FreeBSD) may preempt the process and sends a SIGIO signal to a master process. The master process sends a new terminate message, the kernel switches again to the the child process, and the child process reads the messages instead of an EAGAIN error. And this may repeat over and over. Being that the child process can not exit the cycle and test the termination flag set by the message handler. The fix disallow the master process to send a new terminate message on SIGIO signal reception. It may send the message only on SIGALARM signal.
author Igor Sysoev <igor@sysoev.ru>
date Mon, 01 Feb 2010 15:49:36 +0000
parents cf148caa9347
children d620f497c50f
line wrap: on
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/*
 * Copyright (C) Igor Sysoev
 */


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


u_char  ngx_linux_kern_ostype[50];
u_char  ngx_linux_kern_osrelease[50];

int     ngx_linux_rtsig_max;


static ngx_os_io_t ngx_linux_io = {
    ngx_unix_recv,
    ngx_readv_chain,
    ngx_udp_unix_recv,
    ngx_unix_send,
#if (NGX_HAVE_SENDFILE)
    ngx_linux_sendfile_chain,
    NGX_IO_SENDFILE
#else
    ngx_writev_chain,
    0
#endif
};


ngx_int_t
ngx_os_specific_init(ngx_log_t *log)
{
    struct utsname  u;

    if (uname(&u) == -1) {
        ngx_log_error(NGX_LOG_ALERT, log, ngx_errno, "uname() failed");
        return NGX_ERROR;
    }

    (void) ngx_cpystrn(ngx_linux_kern_ostype, (u_char *) u.sysname,
                       sizeof(ngx_linux_kern_ostype));

    (void) ngx_cpystrn(ngx_linux_kern_osrelease, (u_char *) u.release,
                       sizeof(ngx_linux_kern_osrelease));

#if (NGX_HAVE_RTSIG)
    {
    int        name[2];
    size_t     len;
    ngx_err_t  err;

    name[0] = CTL_KERN;
    name[1] = KERN_RTSIGMAX;
    len = sizeof(ngx_linux_rtsig_max);

    if (sysctl(name, 2, &ngx_linux_rtsig_max, &len, NULL, 0) == -1) {
        err = ngx_errno;

        if (err != NGX_ENOTDIR && err != NGX_ENOSYS) {
            ngx_log_error(NGX_LOG_ALERT, log, err,
                          "sysctl(KERN_RTSIGMAX) failed");

            return NGX_ERROR;
        }

        ngx_linux_rtsig_max = 0;
    }

    }
#endif

    ngx_os_io = ngx_linux_io;

    return NGX_OK;
}


void
ngx_os_specific_status(ngx_log_t *log)
{
    ngx_log_error(NGX_LOG_NOTICE, log, 0, "OS: %s %s",
                  ngx_linux_kern_ostype, ngx_linux_kern_osrelease);

#if (NGX_HAVE_RTSIG)
    ngx_log_error(NGX_LOG_NOTICE, log, 0, "sysctl(KERN_RTSIGMAX): %d",
                  ngx_linux_rtsig_max);
#endif
}