/*

    mtr  --  a network diagnostic tool

    Copyright (C) 2016  Matt Kimball

    This program is free software; you can redistribute it and/or modify

    it under the terms of the GNU General Public License version 2 as

    published by the Free Software Foundation.

    This program is distributed in the hope that it will be useful,

    but WITHOUT ANY WARRANTY; without even the implied warranty of

    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License

    along with this program; if not, write to the Free Software

    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.

*/

#include "wait.h"

#include <io.h>

#include <stdio.h>

#include <windows.h>

#include "command.h"

/*

    Sleep until we receive a new probe response, a new command on the

    command stream, or a probe timeout.  On Windows, this means that

    we will sleep with an alertable wait, as all of these conditions

    use I/O completion routines as notifications of these events.

*/

void wait_for_activity(

    struct command_buffer_t *command_buffer,

    struct net_state_t *net_state)

{

    DWORD wait_result;

    /*

       Start the command read overlapped I/O just prior to sleeping.

       During development of the Cygwin port, there was a bug where the

       overlapped I/O was started earlier in the mtr-packet loop, and

       an intermediate alertable wait could leave us in this Sleep

       without an active command read.  So now we do this here, instead.

     */

    start_read_command(command_buffer);

    /*  Sleep until an I/O completion routine runs  */

    wait_result = SleepEx(INFINITE, TRUE);

    if (wait_result == WAIT_FAILED) {

        fprintf(stderr, "SleepEx failure %d\n", GetLastError());

        exit(EXIT_FAILURE);

    }

}