sigFpe.C

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/*---------------------------------------------------------------------------*\
  =========                 |
  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
   \\    /   O peration     |
    \\  /    A nd           | www.openfoam.com
     \\/     M anipulation  |
-------------------------------------------------------------------------------
    Copyright (C) 2011-2015 OpenFOAM Foundation
    Copyright (C) 2016-2020 OpenCFD Ltd.
-------------------------------------------------------------------------------
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/>.
 
\*---------------------------------------------------------------------------*/
 
#include "sigFpe.H"
#include "error.H"
#include "JobInfo.H"
#include "OSspecific.H"
#include "IOstreams.H"
#include "Switch.H"
#include "UList.H"
 
#include <limits>
 
#if defined(__linux__) && defined(__GNUC__)
    #ifndef __USE_GNU
        #define __USE_GNU      // To use feenableexcept()
    #endif
    #include <fenv.h>
    #include <malloc.h>
#endif
 
#ifdef __APPLE__
    #include "feexceptErsatz.H"
#endif
 
// File-local functions
#include "signalMacros.C"
 
 
// * * * * * * * * * * * * * * Static Data Members * * * * * * * * * * * * * //
 
bool Foam::sigFpe::switchFpe_(Foam::debug::optimisationSwitch("trapFpe", 0));
bool Foam::sigFpe::switchNan_(Foam::debug::optimisationSwitch("setNaN", 0));
 
bool Foam::sigFpe::sigActive_ = false;
bool Foam::sigFpe::nanActive_ = false;
 
 
// * * * * * * * * * * * * * * * Local Functions * * * * * * * * * * * * * * //
 
// Can turn on/off via env variable containing a bool (true|false|on|off ...)
// or by the specified flag
static bool isTrue(const char* envName, bool deflt)
{
    Foam::Switch sw(Foam::Switch::find(Foam::getEnv(envName)));
 
    if (sw.good())
    {
        return static_cast<bool>(sw);
    }
 
    // Env was not set or did not contain a valid bool value
    return deflt;
}
 
 
#ifdef __linux__
extern "C"
{
    extern void* __libc_malloc(size_t size);
 
    // Override the GLIBC malloc to support mallocNan
    void* malloc(size_t size)
    {
        if (Foam::sigFpe::nanActive())
        {
            return Foam::sigFpe::mallocNan(size);
        }
        else
        {
            return __libc_malloc(size);
        }
    }
}
 
 
void* Foam::sigFpe::mallocNan(size_t size)
{
    // Call the low-level GLIBC malloc function
    void* result = __libc_malloc(size);
 
    // Initialize to signalling NaN
    UList<scalar> list(reinterpret_cast<scalar*>(result), size/sizeof(scalar));
    sigFpe::fillNan(list);
 
    return result;
}
#endif  // __linux__
 
 
// * * * * * * * * * * * * * Private Member Functions  * * * * * * * * * * * //
 
void Foam::sigFpe::sigHandler(int)
{
    #if (defined(__linux__) && defined(__GNUC__)) || defined(__APPLE__)
 
    resetHandler("SIGFPE", SIGFPE);
 
    jobInfo.signalEnd();        // Update jobInfo file
    error::printStack(Perr);
    ::raise(SIGFPE);            // Throw signal (to old handler)
 
    #endif  // (__linux__ && __GNUC__) || __APPLE__
}
 
 
// * * * * * * * * * * * * * * * * Constructors  * * * * * * * * * * * * * * //
 
Foam::sigFpe::sigFpe()
{
    set(false);
}
 
 
Foam::sigFpe::ignore::ignore()
:
    wasActive_(sigFpe::active())
{
    if (wasActive_)
    {
        sigFpe::unset();
    }
}
 
 
// * * * * * * * * * * * * * * * * Destructor  * * * * * * * * * * * * * * * //
 
Foam::sigFpe::~sigFpe()
{
    unset(false);
}
 
 
Foam::sigFpe::ignore::~ignore()
{
    restore();
}
 
 
// * * * * * * * * * * * * * * * Member Functions  * * * * * * * * * * * * * //
 
void Foam::sigFpe::ignore::restore()
{
    if (wasActive_)
    {
        sigFpe::set();
    }
    wasActive_ = false;
}
 
 
bool Foam::sigFpe::requested()
{
    return isTrue("FOAM_SIGFPE", switchFpe_);
}
 
 
void Foam::sigFpe::set(bool verbose)
{
    if (!sigActive_ && requested())
    {
        #if (defined(__linux__) && defined(__GNUC__)) || defined(__APPLE__)
 
        feenableexcept
        (
            FE_DIVBYZERO
          | FE_INVALID
          | FE_OVERFLOW
        );
 
        setHandler("SIGFPE", SIGFPE, sigHandler);
 
        sigActive_ = true;
        #endif
 
        if (verbose)
        {
            Info<< "trapFpe: Floating point exception trapping ";
 
            if (sigActive_)
            {
                Info<< "enabled (FOAM_SIGFPE)." << endl;
            }
            else
            {
                Info<< "- not supported on this platform" << endl;
            }
        }
    }
 
 
    nanActive_ = false;
    if (isTrue("FOAM_SETNAN", switchNan_))
    {
        #ifdef __linux__
        nanActive_ = true;
        #endif
 
        if (verbose)
        {
            Info<< "setNaN : Initialise allocated memory to NaN ";
 
            if (nanActive_)
            {
                Info<< "enabled (FOAM_SETNAN)." << endl;
            }
            else
            {
                Info<< " - not supported on this platform" << endl;
            }
        }
    }
}
 
 
void Foam::sigFpe::unset(bool verbose)
{
    #if (defined(__linux__) && defined(__GNUC__)) || defined(__APPLE__)
    if (sigActive_)
    {
        if (verbose)
        {
            Info<< "sigFpe : Disabling floating point exception trapping"
                << endl;
        }
 
        resetHandler("SIGFPE", SIGFPE);
 
        // Reset exception raising
        const int oldExcept = fedisableexcept
        (
            FE_DIVBYZERO
          | FE_INVALID
          | FE_OVERFLOW
        );
 
        if (oldExcept == -1)
        {
            FatalErrorInFunction
                << "Cannot reset SIGFPE trapping"
                << abort(FatalError);
        }
 
        sigActive_ = false;
    }
    #endif
 
    nanActive_ = false;
}
 
 
void Foam::sigFpe::fillNan(UList<scalar>& list)
{
    list = std::numeric_limits<scalar>::signaling_NaN();
}
 
 
// ************************************************************************* //