/*---------------------------------------------------------------------------*\
  =========                 |
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   \\    /   O peration     | Website:  https://openfoam.org
    \\  /    A nd           | Copyright (C) 2011-2023 OpenFOAM Foundation
     \\/     M anipulation  |
-------------------------------------------------------------------------------
License
    This file is part of OpenFOAM.

    OpenFOAM is free software: you can redistribute it and/or modify it
    under the terms of the GNU General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.

    OpenFOAM 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 OpenFOAM.  If not, see <http://www.gnu.org/licenses/>.

Class
    Foam::sigWriteNow

Description
    Signal handler to write when the writeNowSignal is sent.

    writeNowSignal is set in etc/controlDict::OptimisationSwitches, e.g.
    \verbatim
    OptimisationSwitches
    {
        .
        .
        // Force dumping (at next timestep) upon signal (-1 to disable)
        writeNowSignal              10; // SIGUSR1
        .
        .
    }
    \endverbatim

SourceFiles
    sigWriteNow.C

\*---------------------------------------------------------------------------*/

#ifndef sigWriteNow_H
#define sigWriteNow_H

#include <signal.h>

// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

namespace Foam
{

class Time;

/*---------------------------------------------------------------------------*\
                         Class sigWriteNow Declaration
\*---------------------------------------------------------------------------*/

class sigWriteNow
{
    // Private Data

        //- Number of signal to use
        static int signal_;

        //- Pointer to Time
        static Time* runTimePtr_;

        //- Saved old signal trapping setting
        static struct sigaction oldAction_;


    // Private Member Functions

        static void sigHandler(int);


public:

    friend class sigStopAtWriteNow;

    //- wip. Have setter have access to signal_
    friend class addwriteNowSignalToOpt;

    // Constructors

        //- Construct null
        sigWriteNow();

        //- Construct from components
        sigWriteNow(const bool verbose, Time& runTime);


    //- Destructor
    ~sigWriteNow();


    // Member Functions

        //- (re)set signal catcher
        static void set(const bool verbose);

        //- Is active?
        bool active() const;
};


// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

} // End namespace Foam

// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

#endif

// ************************************************************************* //
