ENH: improve code isolation for signal-handling

- file-local static for saving the old action, which moves system
  dependencies out of the header files.

- set/reset of signals as file-local functions

STYLE: use csignal header instead of signal.h

src/OSspecific/POSIX/Make/files

@@ -3,14 +3,16 @@ clockValue/clockValue.C
 cpuInfo/cpuInfo.C
 cpuTime/cpuTime.C
 memInfo/memInfo.C
+
 signals/sigFpe.C
 signals/sigSegv.C
 signals/sigInt.C
 signals/sigQuit.C
 signals/sigStopAtWriteNow.C
 signals/sigWriteNow.C
+signals/timer.C
+
 regExpPosix.C
-timer.C
 fileStat.C
 POSIX.C
 

src/OSspecific/POSIX/cpuTime/cpuTime.H

@@ -41,7 +41,7 @@ SourceFiles
 #define cpuTime_H
 
 #include <string>
-#include <time.h>
+#include <ctime>
 #include <sys/times.h>
 
 // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

src/OSspecific/POSIX/fileMonitor.C

@@ -2,7 +2,7 @@
   =========                 |
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     |
-    \\  /    A nd           |
+    \\  /    A nd           | Copyright (C) 2018 OpenCFD Ltd.
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
                             | Copyright (C) 2011-2016 OpenFOAM Foundation

src/OSspecific/POSIX/fileMonitor.H

@@ -2,7 +2,7 @@
   =========                 |
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     |
-    \\  /    A nd           |
+    \\  /    A nd           | Copyright (C) 2017-2018 OpenCFD Ltd.
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
                             | Copyright (C) 2011-2015 OpenFOAM Foundation
@@ -54,6 +54,7 @@ SourceFiles
 namespace Foam
 {
 
+// Forward Declarations
 class fileMonitor;
 class fileMonitorWatcher;
 
@@ -63,7 +64,6 @@ class fileMonitorWatcher;
 
 class fileMonitor
 {
-
 public:
 
     // Public data types
@@ -79,6 +79,7 @@ public:
         static const Enum<fileState> fileStateNames_;
 
 private:
+
     // Private data
 
         //- Whether to use inotify (requires -DFOAM_USE_INOTIFY, see above)

src/OSspecific/POSIX/fileStat.C

@@ -29,7 +29,6 @@ License
 #include "IOstreams.H"
 #include "timer.H"
 
-#include <signal.h>
 #include <unistd.h>
 #ifndef darwin
     #include <sys/sysmacros.h>

src/OSspecific/POSIX/signals/sigFpe.C

@@ -2,7 +2,7 @@
   =========                 |
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     |
-    \\  /    A nd           | Copyright (C) 2016-2018 OpenCFD Ltd.
+    \\  /    A nd           | Copyright (C) 2016-2019 OpenCFD Ltd.
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
                             | Copyright (C) 2011-2015 OpenFOAM Foundation
@@ -33,6 +33,8 @@ License
 #include "Switch.H"
 #include "UList.H"
 
+#include <limits>
+
 #if defined(__linux__) && defined(__GNUC__)
     #ifndef __USE_GNU
         #define __USE_GNU      // To use feenableexcept()
@@ -47,7 +49,9 @@ License
     #include "feexceptErsatz.H"
 #endif
 
-#include <limits>
+// File-local functions
+#include "signalMacros.C"
+
 
 // * * * * * * * * * * * * * * Static Data Members * * * * * * * * * * * * * //
 
@@ -57,8 +61,6 @@ bool Foam::sigFpe::switchNan_(Foam::debug::optimisationSwitch("setNaN", 0));
 bool Foam::sigFpe::sigActive_ = false;
 bool Foam::sigFpe::nanActive_ = false;
 
-struct sigaction Foam::sigFpe::oldAction_;
-
 
 // * * * * * * * * * * * * * * * Local Functions * * * * * * * * * * * * * * //
 
@@ -123,17 +125,11 @@ void Foam::sigFpe::sigHandler(int)
 {
     #if (defined(__linux__) && defined(__GNUC__)) || defined(darwin)
 
-    // Reset old handling
+    resetHandler("SIGFPE", SIGFPE);
-    if (sigaction(SIGFPE, &oldAction_, nullptr) < 0)
-    {
-        FatalErrorInFunction
-            << "Cannot reset SIGFPE trapping"
-            << abort(FatalError);
-    }
 
     jobInfo.signalEnd();        // Update jobInfo file
     error::printStack(Perr);
-    raise(SIGFPE);              // Throw signal (to old handler)
+    ::raise(SIGFPE);            // Throw signal (to old handler)
 
     #endif  // (__linux__ && __GNUC__) || darwin
 }
@@ -203,17 +199,7 @@ void Foam::sigFpe::set(bool verbose)
           | FE_OVERFLOW
         );
 
-        struct sigaction newAction;
+        setHandler("SIGFPE", SIGFPE, sigHandler);
-        newAction.sa_handler = sigHandler;
-        newAction.sa_flags = SA_NODEFER;
-        sigemptyset(&newAction.sa_mask);
-
-        if (sigaction(SIGFPE, &newAction, &oldAction_) < 0)
-        {
-            FatalErrorInFunction
-                << "Cannot set SIGFPE trapping"
-                << abort(FatalError);
-        }
 
         sigActive_ = true;
 
@@ -293,12 +279,7 @@ void Foam::sigFpe::unset(bool verbose)
                 << endl;
         }
 
-        if (sigaction(SIGFPE, &oldAction_, nullptr) < 0)
+        resetHandler("SIGFPE", SIGFPE);
-        {
-            FatalErrorInFunction
-                << "Cannot reset SIGFPE trapping"
-                << abort(FatalError);
-        }
 
         // Reset exception raising
         const int oldExcept = fedisableexcept

src/OSspecific/POSIX/signals/sigFpe.H

@@ -2,7 +2,7 @@
   =========                 |
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     |
-    \\  /    A nd           | Copyright (C) 2018 OpenCFD Ltd.
+    \\  /    A nd           | Copyright (C) 2018-2019 OpenCFD Ltd.
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
                             | Copyright (C) 2011-2016 OpenFOAM Foundation
@@ -56,7 +56,6 @@ SourceFiles
 #ifndef sigFpe_H
 #define sigFpe_H
 
-#include <signal.h>
 #include "scalar.H"
 
 // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
@@ -64,7 +63,7 @@ SourceFiles
 namespace Foam
 {
 
-// Forward declarations
+// Forward Declarations
 template<class T> class UList;
 
 /*---------------------------------------------------------------------------*\
@@ -73,7 +72,7 @@ template<class T> class UList;
 
 class sigFpe
 {
-    // Private data
+    // Private Data
 
         //- Flag that floating point trapping should be used.
         //  Can override with FOAM_SIGFPE env variable
@@ -83,20 +82,16 @@ class sigFpe
         //  Can override with FOAM_SETNAN env variable
         static bool switchNan_;
 
-        //- Flag to indicate floating point trapping is currently active
+        //- Floating point trapping currently active?
         static bool sigActive_;
 
         //- Flag to indicate mallocNan is currently active
         static bool nanActive_;
 
-        //- Saved old signal trapping setting
-        static struct sigaction oldAction_;
-
 
     // Private Member Functions
 
-        //- Handler for caught signals.
+        //- Handler for caught signals - ends job and prints stack
-        //  Ends job and prints stack
         static void sigHandler(int);
 
 

src/OSspecific/POSIX/signals/sigInt.C

@@ -2,7 +2,7 @@
   =========                 |
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     |
-    \\  /    A nd           |
+    \\  /    A nd           | Copyright (C) 2018-2019 OpenCFD Ltd.
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
                             | Copyright (C) 2011-2015 OpenFOAM Foundation
@@ -30,9 +30,11 @@ License
 #include "JobInfo.H"
 #include "IOstreams.H"
 
-// * * * * * * * * * * * * * * Static Data Members * * * * * * * * * * * * * //
+// File-local functions
+#include "signalMacros.C"
 
-struct sigaction Foam::sigInt::oldAction_;
+
+// * * * * * * * * * * * * * * Static Data Members * * * * * * * * * * * * * //
 
 bool Foam::sigInt::sigActive_ = false;
 
@@ -41,16 +43,10 @@ bool Foam::sigInt::sigActive_ = false;
 
 void Foam::sigInt::sigHandler(int)
 {
-    // Reset old handling
+    resetHandler("SIGINT", SIGINT);
-    if (sigaction(SIGINT, &oldAction_, nullptr) < 0)
-    {
-        FatalErrorInFunction
-            << "Cannot reset SIGINT trapping"
-            << abort(FatalError);
-    }
 
     jobInfo.signalEnd();        // Update jobInfo file
-    raise(SIGINT);              // Throw signal (to old handler)
+    ::raise(SIGINT);            // Throw signal (to old handler)
 }
 
 
@@ -74,35 +70,25 @@ Foam::sigInt::~sigInt()
 
 void Foam::sigInt::set(bool)
 {
-    if (!sigActive_)
+    if (sigActive_)
     {
-        struct sigaction newAction;
+        return;
-        newAction.sa_handler = sigHandler;
-        newAction.sa_flags = SA_NODEFER;
-        sigemptyset(&newAction.sa_mask);
-        if (sigaction(SIGINT, &newAction, &oldAction_) < 0)
-        {
-            FatalErrorInFunction
-                << "Cannot call sigInt::set() more than once"
-                << abort(FatalError);
-        }
-        sigActive_ = true;
     }
+    sigActive_ = true;
+
+    setHandler("SIGINT", SIGINT, sigHandler);
 }
 
 
 void Foam::sigInt::unset(bool)
 {
-    if (sigActive_)
+    if (!sigActive_)
     {
-        if (sigaction(SIGINT, &oldAction_, nullptr) < 0)
+        return;
-        {
-            FatalErrorInFunction
-                << "Cannot set SIGINT trapping"
-                << abort(FatalError);
-        }
-        sigActive_ = false;
     }
+    sigActive_ = false;
+
+    resetHandler("SIGINT", SIGINT);
 }
 
 

src/OSspecific/POSIX/signals/sigInt.H

@@ -2,7 +2,7 @@
   =========                 |
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     |
-    \\  /    A nd           |
+    \\  /    A nd           | Copyright (C) 2018-2019 OpenCFD Ltd.
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
                             | Copyright (C) 2011-2016 OpenFOAM Foundation
@@ -47,8 +47,6 @@ SourceFiles
 #ifndef sigInt_H
 #define sigInt_H
 
-#include <signal.h>
-
 // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
 
 namespace Foam
@@ -62,10 +60,7 @@ class sigInt
 {
     // Private data
 
-        //- Saved old signal trapping setting
+        //- Signal trapping enabled?
-        static struct sigaction oldAction_;
-
-        //- Flag to indicate signal trapping is enabled
         static bool sigActive_;
 
 

src/OSspecific/POSIX/signals/sigQuit.C

@@ -2,7 +2,7 @@
   =========                 |
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     |
-    \\  /    A nd           |
+    \\  /    A nd           | Copyright (C) 2017-2019 OpenCFD Ltd.
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
                             | Copyright (C) 2011-2015 OpenFOAM Foundation
@@ -30,9 +30,11 @@ License
 #include "JobInfo.H"
 #include "IOstreams.H"
 
-// * * * * * * * * * * * * * * Static Data Members * * * * * * * * * * * * * //
+// File-local functions
+#include "signalMacros.C"
 
-struct sigaction Foam::sigQuit::oldAction_;
+
+// * * * * * * * * * * * * * * Static Data Members * * * * * * * * * * * * * //
 
 bool Foam::sigQuit::sigActive_ = false;
 
@@ -41,17 +43,11 @@ bool Foam::sigQuit::sigActive_ = false;
 
 void Foam::sigQuit::sigHandler(int)
 {
-    // Reset old handling
+    resetHandler("SIGQUIT", SIGQUIT);
-    if (sigaction(SIGQUIT, &oldAction_, nullptr) < 0)
-    {
-        FatalErrorInFunction
-            << "Cannot reset SIGQUIT trapping"
-            << abort(FatalError);
-    }
 
     jobInfo.signalEnd();        // Update jobInfo file
     error::printStack(Perr);
-    raise(SIGQUIT);             // Throw signal (to old handler)
+    ::raise(SIGQUIT);           // Throw signal (to old handler)
 }
 
 
@@ -75,35 +71,25 @@ Foam::sigQuit::~sigQuit()
 
 void Foam::sigQuit::set(bool)
 {
-    if (!sigActive_)
+    if (sigActive_)
     {
-        struct sigaction newAction;
+        return;
-        newAction.sa_handler = sigHandler;
-        newAction.sa_flags = SA_NODEFER;
-        sigemptyset(&newAction.sa_mask);
-        if (sigaction(SIGQUIT, &newAction, &oldAction_) < 0)
-        {
-            FatalErrorInFunction
-                << "Cannot call more than once"
-                << abort(FatalError);
-        }
-        sigActive_ = true;
     }
+    sigActive_ = true;
+
+    setHandler("SIGQUIT", SIGQUIT, sigHandler);
 }
 
 
 void Foam::sigQuit::unset(bool)
 {
-    if (sigActive_)
+    if (!sigActive_)
     {
-        if (sigaction(SIGQUIT, &oldAction_, nullptr) < 0)
+        return;
-        {
-            FatalErrorInFunction
-                << "Cannot unset SIGQUIT trapping"
-                << abort(FatalError);
-        }
-        sigActive_ = false;
     }
+    sigActive_ = false;
+
+    resetHandler("SIGQUIT", SIGQUIT);
 }
 
 

src/OSspecific/POSIX/signals/sigQuit.H

@@ -2,7 +2,7 @@
   =========                 |
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     |
-    \\  /    A nd           |
+    \\  /    A nd           | Copyright (C) 2017-2019 OpenCFD Ltd.
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
                             | Copyright (C) 2011-2016 OpenFOAM Foundation
@@ -46,8 +46,6 @@ SourceFiles
 #ifndef sigQuit_H
 #define sigQuit_H
 
-#include <signal.h>
-
 // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
 
 namespace Foam
@@ -59,12 +57,9 @@ namespace Foam
 
 class sigQuit
 {
-    // Private data
+    // Private Data
 
-        //- Saved old signal trapping setting
+        //- Signal trapping enabled?
-        static struct sigaction oldAction_;
-
-        //- Flag to indicate signal trapping is enabled
         static bool sigActive_;
 
 
@@ -86,7 +81,7 @@ public:
     ~sigQuit();
 
 
-    // Member functions
+    // Member Functions
 
         //- Activate SIGQUIT signal handler
         static void set(bool verbose=false);

src/OSspecific/POSIX/signals/sigSegv.C

@@ -2,7 +2,7 @@
   =========                 |
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     |
-    \\  /    A nd           |
+    \\  /    A nd           | Copyright (C) 2018-2019 OpenCFD Ltd.
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
                             | Copyright (C) 2011-2015 OpenFOAM Foundation
@@ -30,9 +30,11 @@ License
 #include "JobInfo.H"
 #include "IOstreams.H"
 
-// * * * * * * * * * * * * * * Static Data Members * * * * * * * * * * * * * //
+// File-local functions
+#include "signalMacros.C"
 
-struct sigaction Foam::sigSegv::oldAction_;
+
+// * * * * * * * * * * * * * * Static Data Members * * * * * * * * * * * * * //
 
 bool Foam::sigSegv::sigActive_ = false;
 
@@ -41,17 +43,11 @@ bool Foam::sigSegv::sigActive_ = false;
 
 void Foam::sigSegv::sigHandler(int)
 {
-    // Reset old handling
+    resetHandler("SIGSEGV", SIGSEGV);
-    if (sigaction(SIGSEGV, &oldAction_, nullptr) < 0)
-    {
-        FatalErrorInFunction
-            << "Cannot reset SIGSEGV trapping"
-            << abort(FatalError);
-    }
 
     jobInfo.signalEnd();        // Update jobInfo file
     error::printStack(Perr);
-    raise(SIGSEGV);             // Throw signal (to old handler)
+    ::raise(SIGSEGV);           // Throw signal (to old handler)
 }
 
 
@@ -75,35 +71,25 @@ Foam::sigSegv::~sigSegv()
 
 void Foam::sigSegv::set(bool)
 {
-    if (!sigActive_)
+    if (sigActive_)
     {
-        struct sigaction newAction;
+        return;
-        newAction.sa_handler = sigHandler;
-        newAction.sa_flags = SA_NODEFER;
-        sigemptyset(&newAction.sa_mask);
-        if (sigaction(SIGSEGV, &newAction, &oldAction_) < 0)
-        {
-            FatalErrorInFunction
-                << "Cannot call more than once"
-                << abort(FatalError);
-        }
-        sigActive_ = true;
     }
+    sigActive_ = true;
+
+    setHandler("SIGSEGV", SIGSEGV, sigHandler);
 }
 
 
 void Foam::sigSegv::unset(bool)
 {
-    if (sigActive_)
+    if (!sigActive_)
     {
-        if (sigaction(SIGSEGV, &oldAction_, nullptr) < 0)
+        return;
-        {
-            FatalErrorInFunction
-                << "Cannot unset SIGSEGV trapping"
-                << abort(FatalError);
-        }
-        sigActive_ = false;
     }
+    sigActive_ = false;
+
+    resetHandler("SIGSEGV", SIGSEGV);
 }
 
 

src/OSspecific/POSIX/signals/sigSegv.H

@@ -2,7 +2,7 @@
   =========                 |
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     |
-    \\  /    A nd           |
+    \\  /    A nd           | Copyright (C) 2018-2019 OpenCFD Ltd.
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
                             | Copyright (C) 2011-2016 OpenFOAM Foundation
@@ -46,8 +46,6 @@ SourceFiles
 #ifndef sigSegv_H
 #define sigSegv_H
 
-#include <signal.h>
-
 // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
 
 namespace Foam
@@ -59,12 +57,9 @@ namespace Foam
 
 class sigSegv
 {
-    // Private data
+    // Private Data
 
-        //- Saved old signal trapping setting
+        //- Signal trapping enabled?
-        static struct sigaction oldAction_;
-
-        //- Flag to indicate signal trapping is enabled
         static bool sigActive_;
 
 

src/OSspecific/POSIX/signals/sigStopAtWriteNow.C

@@ -2,7 +2,7 @@
   =========                 |
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     |
-    \\  /    A nd           |
+    \\  /    A nd           | Copyright (C) 2016-2019 OpenCFD Ltd.
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
                             | Copyright (C) 2011-2016 OpenFOAM Foundation
@@ -25,12 +25,17 @@ License
 
 \*---------------------------------------------------------------------------*/
 
+#include "sigWriteNow.H"
 #include "sigStopAtWriteNow.H"
 #include "error.H"
 #include "JobInfo.H"
 #include "IOstreams.H"
 #include "Time.H"
 
+// File-local functions
+#include "signalMacros.C"
+
+
 // * * * * * * * * * * * * * * Static Data Members * * * * * * * * * * * * * //
 
 // Signal number to catch
@@ -39,21 +44,19 @@ int Foam::sigStopAtWriteNow::signal_
     Foam::debug::optimisationSwitch("stopAtWriteNowSignal", -1)
 );
 
-Foam::Time const* Foam::sigStopAtWriteNow::runTimePtr_ = nullptr;
+// Pointer to Time (file-local variable)
+static Foam::Time const* runTimePtr_ = nullptr;
 
-struct sigaction Foam::sigStopAtWriteNow::oldAction_;
 
+// * * * * * * * * * * * * * * * Local Classes * * * * * * * * * * * * * * * //
 
 namespace Foam
 {
 // Register re-reader
-class addstopAtWriteNowSignalToOpt
+struct addstopAtWriteNowSignalToOpt
 :
     public ::Foam::simpleRegIOobject
 {
-
-public:
-
     addstopAtWriteNowSignalToOpt(const char* name)
     :
         ::Foam::simpleRegIOobject(Foam::debug::addOptimisationObject, name)
@@ -85,15 +88,9 @@ addstopAtWriteNowSignalToOpt addstopAtWriteNowSignalToOpt_
 
 void Foam::sigStopAtWriteNow::sigHandler(int)
 {
-    // Reset old handling
+    resetHandler("stopAtWriteNow", signal_);
-    if (sigaction(signal_, &oldAction_, nullptr) < 0)
-    {
-        FatalErrorInFunction
-            << "Cannot reset " << signal_ << " trapping"
-            << abort(FatalError);
-    }
 
-    jobInfo.signalEnd();        // Update jobInfo file
+    jobInfo.signalEnd(); // Update jobInfo file
 
     if (runTimePtr_)
     {
@@ -113,7 +110,7 @@ Foam::sigStopAtWriteNow::sigStopAtWriteNow()
 
 Foam::sigStopAtWriteNow::sigStopAtWriteNow(const Time& runTime, bool verbose)
 {
-    runTimePtr_ = &runTime;      // Store runTime
+    runTimePtr_ = &runTime; // Store runTime
     set(verbose);
 }
 
@@ -122,61 +119,55 @@ Foam::sigStopAtWriteNow::sigStopAtWriteNow(const Time& runTime, bool verbose)
 
 Foam::sigStopAtWriteNow::~sigStopAtWriteNow()
 {
-    // Reset old handling
+    if (!active())
-    if (signal_ > 0)
     {
-        if (sigaction(signal_, &oldAction_, nullptr) < 0)
+        return;
-        {
-            FatalErrorInFunction
-                << "Cannot reset " << signal_ << " trapping"
-                << abort(FatalError);
-        }
     }
+
+    resetHandler("stopAtWriteNow", signal_);
 }
 
 
 // * * * * * * * * * * * * * * * Member Functions  * * * * * * * * * * * * * //
 
-void Foam::sigStopAtWriteNow::set(bool verbose)
+bool Foam::sigStopAtWriteNow::active()
-{
-    if (signal_ > 0)
-    {
-        // Check that the signal is different from the writeNowSignal
-        if (sigWriteNow::signal_ == signal_)
-        {
-            FatalErrorInFunction
-                << "stopAtWriteNowSignal : " << signal_
-                << " cannot be the same as the writeNowSignal."
-                << " Please change this in the etc/controlDict."
-                << exit(FatalError);
-        }
-
-
-        struct sigaction newAction;
-        newAction.sa_handler = sigHandler;
-        newAction.sa_flags = SA_NODEFER;
-        sigemptyset(&newAction.sa_mask);
-        if (sigaction(signal_, &newAction, &oldAction_) < 0)
-        {
-            FatalErrorInFunction
-                << "Cannot set " << signal_ << " trapping"
-                << abort(FatalError);
-        }
-
-        if (verbose)
-        {
-            Info<< "sigStopAtWriteNow :"
-                << " Enabling writing and stopping upon signal " << signal_
-                << endl;
-        }
-    }
-}
-
-
-bool Foam::sigStopAtWriteNow::active() const
 {
     return signal_ > 0;
 }
 
 
+int Foam::sigStopAtWriteNow::signalNumber()
+{
+    return signal_;
+}
+
+
+void Foam::sigStopAtWriteNow::set(bool verbose)
+{
+    if (!active())
+    {
+        return;
+    }
+
+    // Check that the signal is different from the writeNowSignal
+    if (sigWriteNow::signalNumber() == signal_)
+    {
+        FatalErrorInFunction
+            << "stopAtWriteNowSignal : " << signal_
+            << " cannot be the same as the writeNowSignal."
+            << " Please change this in the etc/controlDict."
+            << exit(FatalError);
+    }
+
+    if (verbose)
+    {
+        Info<< "sigStopAtWriteNow :"
+            << " Enabling writing and stopping upon signal " << signal_
+            << endl;
+    }
+
+    setHandler("stopAtWriteNow", signal_, sigHandler);
+}
+
+
 // ************************************************************************* //

src/OSspecific/POSIX/signals/sigStopAtWriteNow.H

@@ -2,7 +2,7 @@
   =========                 |
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     |
-    \\  /    A nd           |
+    \\  /    A nd           | Copyright (C) 2016-2019 OpenCFD Ltd.
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
                             | Copyright (C) 2011-2016 OpenFOAM Foundation
@@ -27,10 +27,8 @@ Class
     Foam::sigStopAtWriteNow
 
 Description
-    Signal handler for interupt defined by
+    Signal handler to write and stop the job.
-        OptimisationSwitches::stopAtWriteNowSignal
+    The interrupt is defined by OptimisationSwitches::stopAtWriteNowSignal
-
-    Write and stop the job.
 
 SourceFiles
     sigStopAtWriteNow.C
@@ -40,32 +38,25 @@ SourceFiles
 #ifndef sigStopAtWriteNow_H
 #define sigStopAtWriteNow_H
 
-#include <signal.h>
-
 // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
 
 namespace Foam
 {
 
+// Forward Declarations
 class Time;
 
 /*---------------------------------------------------------------------------*\
-                           Class sigStopAtWriteNow Declaration
+                      Class sigStopAtWriteNow Declaration
 \*---------------------------------------------------------------------------*/
 
 class sigStopAtWriteNow
 {
-    // Private data
+    // Private Data
 
-        //- Number of signal to use
+        //- Signal number to use
         static int signal_;
 
-        //- Pointer to Time
-        static Time const* runTimePtr_;
-
-        //- Saved old signal trapping setting
-        static struct sigaction oldAction_;
-
 
     // Private Member Functions
 
@@ -92,13 +83,16 @@ public:
     ~sigStopAtWriteNow();
 
 
-    // Member functions
+    // Member Functions
-
-        //- (re)set signal catcher
-        static void set(bool verbose=false);
 
         //- Is active?
-        bool active() const;
+        static bool active();
+
+        //- Signal number being used
+        static int signalNumber();
+
+        //- Set/reset signal handler
+        static void set(bool verbose=false);
 };
 
 

src/OSspecific/POSIX/signals/sigWriteNow.C

@@ -2,7 +2,7 @@
   =========                 |
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     |
-    \\  /    A nd           |
+    \\  /    A nd           | Copyright (C) 2016-2019 OpenCFD Ltd.
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
                             | Copyright (C) 2011-2016 OpenFOAM Foundation
@@ -31,6 +31,10 @@ License
 #include "IOstreams.H"
 #include "Time.H"
 
+// File-local functions
+#include "signalMacros.C"
+
+
 // * * * * * * * * * * * * * * Static Data Members * * * * * * * * * * * * * //
 
 // Signal number to catch
@@ -39,22 +43,20 @@ int Foam::sigWriteNow::signal_
     Foam::debug::optimisationSwitch("writeNowSignal", -1)
 );
 
-Foam::Time* Foam::sigWriteNow::runTimePtr_ = nullptr;
+// Pointer to Time (file-local variable)
+static Foam::Time* runTimePtr_ = nullptr;
 
-struct sigaction Foam::sigWriteNow::oldAction_;
 
+// * * * * * * * * * * * * * * * Local Classes * * * * * * * * * * * * * * * //
 
 namespace Foam
 {
 
 // Register re-reader
-class addwriteNowSignalToOpt
+struct addwriteNowSignalToOpt
 :
     public ::Foam::simpleRegIOobject
 {
-
-public:
-
     addwriteNowSignalToOpt(const char* name)
     :
         ::Foam::simpleRegIOobject(Foam::debug::addOptimisationObject, name)
@@ -100,7 +102,7 @@ Foam::sigWriteNow::sigWriteNow()
 
 Foam::sigWriteNow::sigWriteNow(Time& runTime, bool verbose)
 {
-    runTimePtr_ = &runTime;     // Store runTime
+    runTimePtr_ = &runTime; // Store runTime
     set(verbose);
 }
 
@@ -109,50 +111,44 @@ Foam::sigWriteNow::sigWriteNow(Time& runTime, bool verbose)
 
 Foam::sigWriteNow::~sigWriteNow()
 {
-    // Reset old handling
+    if (!active())
-    if (signal_ > 0)
     {
-        if (sigaction(signal_, &oldAction_, nullptr) < 0)
+        return;
-        {
-            FatalErrorInFunction
-                << "Cannot reset " << signal_ << " trapping"
-                << abort(FatalError);
-        }
     }
+
+    resetHandler("writeNow", signal_);
 }
 
 
 // * * * * * * * * * * * * * * * Member Functions  * * * * * * * * * * * * * //
 
-void Foam::sigWriteNow::set(bool verbose)
+bool Foam::sigWriteNow::active()
-{
-    if (signal_ >= 0)
-    {
-        struct sigaction newAction;
-        newAction.sa_handler = sigHandler;
-        newAction.sa_flags = SA_NODEFER;
-        sigemptyset(&newAction.sa_mask);
-        if (sigaction(signal_, &newAction, &oldAction_) < 0)
-        {
-            FatalErrorInFunction
-                << "Cannot set " << signal_ << " trapping"
-                << abort(FatalError);
-        }
-
-        if (verbose)
-        {
-            Info<< "sigWriteNow :"
-                << " Enabling writing upon signal " << signal_
-                << endl;
-        }
-    }
-}
-
-
-bool Foam::sigWriteNow::active() const
 {
     return signal_ > 0;
 }
 
 
+int Foam::sigWriteNow::signalNumber()
+{
+    return signal_;
+}
+
+
+void Foam::sigWriteNow::set(bool verbose)
+{
+    if (!active())
+    {
+        return;
+    }
+
+    if (verbose)
+    {
+        Info<< "sigWriteNow :"
+            << " Enabling writing upon signal " << signal_ << nl;
+    }
+
+    setHandler("writeNow", signal_, sigHandler);
+}
+
+
 // ************************************************************************* //

src/OSspecific/POSIX/signals/sigWriteNow.H

@@ -2,7 +2,7 @@
   =========                 |
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     |
-    \\  /    A nd           |
+    \\  /    A nd           | Copyright (C) 2016-2019 OpenCFD Ltd.
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
                             | Copyright (C) 2011-2016 OpenFOAM Foundation
@@ -27,9 +27,8 @@ Class
     Foam::sigWriteNow
 
 Description
-    Signal handler for interupt defined by OptimisationSwitches::writeNowSignal
+    Signal handler to write once and continue.
-
+    The interrupt is defined by OptimisationSwitches::writeNowSignal
-    Write once and continue.
 
 SourceFiles
     sigWriteNow.C
@@ -39,32 +38,25 @@ SourceFiles
 #ifndef sigWriteNow_H
 #define sigWriteNow_H
 
-#include <signal.h>
-
 // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
 
 namespace Foam
 {
 
+// Forward Declarations
 class Time;
 
 /*---------------------------------------------------------------------------*\
-                           Class sigWriteNow Declaration
+                         Class sigWriteNow Declaration
 \*---------------------------------------------------------------------------*/
 
 class sigWriteNow
 {
-    // Private data
+    // Private Data
 
-        //- Number of signal to use
+        //- Signal number to use
         static int signal_;
 
-        //- Pointer to Time
-        static Time* runTimePtr_;
-
-        //- Saved old signal trapping setting
-        static struct sigaction oldAction_;
-
 
     // Private Member Functions
 
@@ -74,8 +66,6 @@ class sigWriteNow
 
 public:
 
-    friend class sigStopAtWriteNow;
-
     //- Allow setter access to signal_
     friend class addwriteNowSignalToOpt;
 
@@ -96,9 +86,12 @@ public:
     // Member Functions
 
         //- Is active?
-        bool active() const;
+        static bool active();
 
-        //- (re)set signal catcher
+        //- The signal number being used
+        static int signalNumber();
+
+        //- Set/reset signal handler
         static void set(bool verbose=false);
 
 };

src/OSspecific/POSIX/signals/signalMacros.C

@@ -0,0 +1,74 @@
+/*---------------------------------------------------------------------------*\
+  =========                 |
+  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
+   \\    /   O peration     |
+    \\  /    A nd           | Copyright (C) 2019 OpenCFD Ltd.
+     \\/     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/>.
+
+Description
+    File-local code for setting/resetting signal handlers.
+
+SourceFiles
+    signalMacros.C
+
+\*---------------------------------------------------------------------------*/
+
+#include "error.H"
+#include <csignal>
+
+// * * * * * * * * * * * * * * * Local Functions * * * * * * * * * * * * * * //
+
+namespace Foam
+{
+
+// Saved old signal trapping setting (file-local variable)
+static struct sigaction oldAction_;
+
+
+static void resetHandler(const char *what, int sigNum)
+{
+    if (sigaction(sigNum, &oldAction_, nullptr) < 0)
+    {
+        FatalError
+            << "Cannot unset " << what << " signal (" << sigNum
+            << ") trapping" << endl
+            << abort(FatalError);
+    }
+}
+
+
+static void setHandler(const char *what, int sigNum, void (*handler)(int))
+{
+    struct sigaction newAction;
+    newAction.sa_handler = handler;
+    newAction.sa_flags = SA_NODEFER;
+    sigemptyset(&newAction.sa_mask);
+    if (sigaction(sigNum, &newAction, &oldAction_) < 0)
+    {
+        FatalError
+            << "Could not set " << what << " signal (" << sigNum
+            << ") trapping" << endl
+            << abort(FatalError);
+    }
+}
+
+} // End namespace Foam
+
+
+// ************************************************************************* //

src/OSspecific/POSIX/signals/timer.C

@@ -0,0 +1,114 @@
+/*---------------------------------------------------------------------------*\
+  =========                 |
+  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
+   \\    /   O peration     |
+    \\  /    A nd           | Copyright (C) 2004-2010, 2019 OpenCFD Ltd.
+     \\/     M anipulation  |
+-------------------------------------------------------------------------------
+                            | Copyright (C) 2011-2016 OpenFOAM Foundation
+-------------------------------------------------------------------------------
+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 "error.H"
+#include "timer.H"
+
+#include <unistd.h>
+
+// File-local functions
+#include "signalMacros.C"
+
+
+// * * * * * * * * * * * * * * Static Data Members * * * * * * * * * * * * * //
+
+namespace Foam
+{
+    defineTypeNameAndDebug(timer, 0);
+}
+
+jmp_buf Foam::timer::envAlarm;
+
+unsigned int Foam::timer::oldTimeOut_ = 0;
+
+
+// * * * * * * * * * * * * * Private Member Functions  * * * * * * * * * * * //
+
+void Foam::timer::sigHandler(int)
+{
+    DebugInFunction<< "Timed out. Jumping." << endl;
+
+    longjmp(envAlarm, 1);
+}
+
+
+// * * * * * * * * * * * * * * * * Constructors  * * * * * * * * * * * * * * //
+
+Foam::timer::timer(unsigned int seconds)
+:
+    timeOut_(seconds)
+{
+    if (!timeOut_)
+    {
+        return;
+    }
+
+    // Singleton since handler is static function
+    if (oldTimeOut_)
+    {
+        FatalErrorInFunction
+            << "timer already used."
+            << abort(FatalError);
+    }
+
+    // Set alarm signal handler
+    // - do not block any signals while in it
+    // - clear list of signals to mask
+
+    setHandler("SIGALRM", SIGALRM, sigHandler);
+
+    // Set alarm timer
+    oldTimeOut_ = ::alarm(timeOut_);
+
+    DebugInFunction
+        << "Installing timeout " << int(timeOut_) << " seconds"
+        << " (overriding old timeout " << int(oldTimeOut_) << ")." << endl;
+}
+
+
+// * * * * * * * * * * * * * * * * Destructor  * * * * * * * * * * * * * * * //
+
+Foam::timer::~timer()
+{
+    if (!timeOut_)
+    {
+        return;
+    }
+
+    DebugInFunction
+        << "timeOut=" << int(timeOut_)
+        << " : resetting timeOut to " << int(oldTimeOut_) << endl;
+
+    // Reset alarm timer
+    ::alarm(oldTimeOut_);
+    oldTimeOut_ = 0;
+
+    resetHandler("SIGALRM", SIGALRM);
+}
+
+
+// ************************************************************************* //

src/OSspecific/POSIX/signals/timer.H

@@ -2,7 +2,7 @@
   =========                 |
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     |
-    \\  /    A nd           |
+    \\  /    A nd           | Copyright (C) 2019 OpenCFD Ltd.
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
                             | Copyright (C) 2011-2015 OpenFOAM Foundation
@@ -46,14 +46,15 @@ Description
     Constructor set signal handler on sigalarm and alarm(). Destructor
     clears these.
 
-    timedOut is macro because setjmp can't be in member function of timer.
-    ?something to do with stack frames.
-
 Warning
     The setjmp restores complete register state so including local vars
     held in regs. So if in blocking part something gets calced in a stack
     based variable make sure it is declared 'volatile'.
 
+Note
+    timedOut is macro because setjmp can't be in member function of timer.
+    ?something to do with stack frames.
+
 SourceFiles
     timer.C
 
@@ -63,16 +64,14 @@ SourceFiles
 #define timer_H
 
 #include "className.H"
-
+#include <csetjmp>
-#include <signal.h>
-#include <setjmp.h>
 
 // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
 
-//- Check it a timeout has occured
+//- Check if timeout has occurred
 //  keep setjmp in same stack frame so no function calls
 #define timedOut(x) \
-    (((x).newTimeOut_ > 0) ? setjmp(Foam::timer::envAlarm) : false)
+    ((x).timeOut_ ? setjmp(Foam::timer::envAlarm) : false)
 
 namespace Foam
 {
@@ -83,10 +82,7 @@ namespace Foam
 
 class timer
 {
-    // Private data
+    // Private Data
-
-        //- Old signal masks
-        static struct sigaction oldAction_;
 
         //- Old alarm() value
         static unsigned int oldTimeOut_;
@@ -95,18 +91,18 @@ class timer
     // Private Member Functions
 
         //- Alarm handler
-        static void signalHandler(int);
+        static void sigHandler(int);
 
 
 public:
 
-    // Public data
+    // Public Data
 
         //- Declare name of the class and its debug switch
         ClassName("timer");
 
-        //- Current time out value. Needed by macro timedOut
+        //- The time-out value (seconds). Needed by macro timedOut
-        unsigned int newTimeOut_;
+        unsigned int timeOut_;
 
         //- State for setjmp. Needed by macro timedOut
         static jmp_buf envAlarm;
@@ -118,7 +114,7 @@ public:
         explicit timer(unsigned int seconds);
 
 
-    //- Destructor
+    //- Destructor. Restores the alarm and signal handler as required.
     ~timer();
 };
 

src/OSspecific/POSIX/timer.C

@@ -1,133 +0,0 @@
-/*---------------------------------------------------------------------------*\
-  =========                 |
-  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
-   \\    /   O peration     |
-    \\  /    A nd           |
-     \\/     M anipulation  |
--------------------------------------------------------------------------------
-                            | Copyright (C) 2011-2016 OpenFOAM Foundation
--------------------------------------------------------------------------------
-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 <unistd.h>
-
-#include "error.H"
-#include "timer.H"
-
-// * * * * * * * * * * * * * * Static Data Members * * * * * * * * * * * * * //
-
-namespace Foam
-{
-defineTypeNameAndDebug(timer, 0);
-
-jmp_buf timer::envAlarm;
-
-struct sigaction timer::oldAction_;
-
-unsigned int timer::oldTimeOut_ = 0;
-}
-
-
-// * * * * * * * * * * * * * Static Member Functions * * * * * * * * * * * * //
-
-void Foam::timer::signalHandler(int)
-{
-    if (debug)
-    {
-        InfoInFunction<< "Timed out. Jumping."
-            << endl;
-    }
-    longjmp(envAlarm, 1);
-}
-
-// * * * * * * * * * * * * * * * * Constructors  * * * * * * * * * * * * * * //
-
-Foam::timer::timer(const unsigned int newTimeOut)
-:
-    newTimeOut_(newTimeOut)
-{
-
-    if (newTimeOut > 0)
-    {
-        // Is singleton since handler is static function
-        if (oldTimeOut_ != 0)
-        {
-            FatalErrorInFunction
-                << "timer already used."
-                << abort(FatalError);
-        }
-
-        // Install alarm signal handler:
-        // - do not block any signals while in it
-        // - clear list of signals to mask
-        struct sigaction newAction;
-        newAction.sa_handler = timer::signalHandler;
-        newAction.sa_flags = SA_NODEFER;
-        sigemptyset(&newAction.sa_mask);
-
-        if (sigaction(SIGALRM, &newAction, &oldAction_) < 0)
-        {
-            FatalErrorInFunction
-                << "sigaction(SIGALRM) error"
-                << abort(FatalError);
-        }
-
-        oldTimeOut_ = ::alarm(newTimeOut);
-
-        if (debug)
-        {
-            InfoInFunction
-                << "Installing timeout " << int(newTimeOut_)
-                << " seconds"
-                << " (overriding old timeout " << int(oldTimeOut_)
-                << ")." << endl;
-        }
-    }
-}
-
-
-// * * * * * * * * * * * * * * * * Destructor  * * * * * * * * * * * * * * * //
-
-Foam::timer::~timer()
-{
-    if (newTimeOut_ > 0)
-    {
-        if (debug)
-        {
-            InfoInFunction
-                << "timeOut=" << int(newTimeOut_)
-                << " : resetting timeOut to " << int(oldTimeOut_) << endl;
-        }
-
-        // Reset timer
-        ::alarm(oldTimeOut_);
-        oldTimeOut_ = 0;
-
-        // Restore signal handler
-        if (sigaction(SIGALRM, &oldAction_, nullptr) < 0)
-        {
-            FatalErrorInFunction
-                << "sigaction(SIGALRM) error"
-                << abort(FatalError);
-        }
-    }
-}
-
-
-// ************************************************************************* //