ENH: improve abort/exception handling in error class (#1780)

- previously setting FOAM_ABORT would preempt checks for throwing
  exceptions.

  Now check for throwing first, to allow try/catch code to do its job.
  However, ignore exception throwing for abort(). These are used
  infrequently in the code, but indicate that recovery is deemed
  impossible.

STYLE: use unique_ptr for internal stream buffer management

src/OpenFOAM/db/error/IOerror.C

@@ -170,14 +170,14 @@ Foam::IOerror::operator Foam::dictionary() const
 }
 
 
-// * * * * * * * * * * * * * * * Member Functions  * * * * * * * * * * * * * //
+// * * * * * * * * * * * * * Private Member Functions  * * * * * * * * * * * //
 
-void Foam::IOerror::exitOrAbort(const int, const bool isAbort)
+void Foam::IOerror::exitOrAbort(const int errNo, const bool isAbort)
 {
-    if (!throwExceptions_ && JobInfo::constructed)
+    if (!throwing_ && JobInfo::constructed)
     {
         jobInfo.add("FatalIOError", operator dictionary());
-        if (isAbort)
+        if (isAbort || hasEnv("FOAM_ABORT"))
         {
             jobInfo.abort();
         }
@@ -187,14 +187,7 @@ void Foam::IOerror::exitOrAbort(const int, const bool isAbort)
         }
     }
 
-    if (hasEnv("FOAM_ABORT"))
-    {
-        Perr<< nl << *this << nl
-            << "\nFOAM aborting (FOAM_ABORT set)\n" << endl;
-        printStack(Perr);
-        std::abort();
-    }
-    else if (throwExceptions_)
+    if (throwing_ && !isAbort)
     {
         // Make a copy of the error to throw
         IOerror errorException(*this);
@@ -204,20 +197,27 @@ void Foam::IOerror::exitOrAbort(const int, const bool isAbort)
 
         throw errorException;
     }
+    else if (hasEnv("FOAM_ABORT"))
+    {
+        Perr<< nl << *this << nl
+            << "\nFOAM aborting (FOAM_ABORT set)\n" << endl;
+        error::printStack(Perr);
+        std::abort();
+    }
     else if (Pstream::parRun())
     {
         if (isAbort)
         {
             Perr<< nl << *this << nl
                 << "\nFOAM parallel run aborting\n" << endl;
-            printStack(Perr);
+            error::printStack(Perr);
             Pstream::abort();
         }
         else
         {
             Perr<< nl << *this << nl
                 << "\nFOAM parallel run exiting\n" << endl;
-            Pstream::exit(1);
+            Pstream::exit(errNo);
         }
     }
     else
@@ -226,7 +226,7 @@ void Foam::IOerror::exitOrAbort(const int, const bool isAbort)
         {
             Perr<< nl << *this << nl
                 << "\nFOAM aborting\n" << endl;
-            printStack(Perr);
+            error::printStack(Perr);
 
             #ifdef _WIN32
             std::exit(1);  // Prefer exit() to avoid unnecessary warnings
@@ -238,15 +238,17 @@ void Foam::IOerror::exitOrAbort(const int, const bool isAbort)
         {
             Perr<< nl << *this << nl
                 << "\nFOAM exiting\n" << endl;
-            std::exit(1);
+            std::exit(errNo);
         }
     }
 }
 
 
+// * * * * * * * * * * * * * * * Member Functions  * * * * * * * * * * * * * //
+
 void Foam::IOerror::exit(const int)
 {
-    exitOrAbort(1, hasEnv("FOAM_ABORT"));
+    exitOrAbort(1, false);
 }
 
 

src/OpenFOAM/db/error/error.C

@@ -79,17 +79,9 @@ Foam::error::error(const string& title)
     functionName_("unknown"),
     sourceFileName_("unknown"),
     sourceFileLineNumber_(0),
-    throwExceptions_(false),
+    throwing_(false),
     messageStreamPtr_(new OStringStream())
-{
-    if (!messageStreamPtr_->good())
-    {
-        Perr<< nl
-            << "error::error(const string&) : cannot open error stream"
-            << endl;
-        exit(1);
-    }
-}
+{}
 
 
 Foam::error::error(const dictionary& errDict)
@@ -99,17 +91,9 @@ Foam::error::error(const dictionary& errDict)
     functionName_(errDict.get<string>("functionName")),
     sourceFileName_(errDict.get<string>("sourceFileName")),
     sourceFileLineNumber_(errDict.get<label>("sourceFileLineNumber")),
-    throwExceptions_(false),
+    throwing_(false),
     messageStreamPtr_(new OStringStream())
-{
-    if (!messageStreamPtr_->good())
-    {
-        Perr<< nl
-            << "error::error(const dictionary&) : cannot open error stream"
-            << endl;
-        exit(1);
-    }
-}
+{}
 
 
 Foam::error::error(const error& err)
@@ -119,7 +103,7 @@ Foam::error::error(const error& err)
     functionName_(err.functionName_),
     sourceFileName_(err.sourceFileName_),
     sourceFileLineNumber_(err.sourceFileLineNumber_),
-    throwExceptions_(err.throwExceptions_),
+    throwing_(err.throwing_),
     messageStreamPtr_(new OStringStream(*err.messageStreamPtr_))
 {}
 
@@ -127,9 +111,7 @@ Foam::error::error(const error& err)
 // * * * * * * * * * * * * * * * * Destructor  * * * * * * * * * * * * * * * //
 
 Foam::error::~error() noexcept
-{
-    delete messageStreamPtr_;
-}
+{}
 
 
 // * * * * * * * * * * * * * * * Member Operators  * * * * * * * * * * * * * //
@@ -208,27 +190,14 @@ Foam::error::operator Foam::dictionary() const
     return errDict;
 }
 
-
-// * * * * * * * * * * * * * * * Member Functions  * * * * * * * * * * * * * //
-
-Foam::string Foam::error::message() const
-{
-    return messageStreamPtr_->str();
-}
-
-
-void Foam::error::clear() const
-{
-    return messageStreamPtr_->reset();
-}
-
+// * * * * * * * * * * * * * Private Member Functions  * * * * * * * * * * * //
 
 void Foam::error::exitOrAbort(const int errNo, const bool isAbort)
 {
-    if (!throwExceptions_ && JobInfo::constructed)
+    if (!throwing_ && JobInfo::constructed)
     {
         jobInfo.add("FatalError", operator dictionary());
-        if (isAbort)
+        if (isAbort || hasEnv("FOAM_ABORT"))
         {
             jobInfo.abort();
         }
@@ -238,14 +207,7 @@ void Foam::error::exitOrAbort(const int errNo, const bool isAbort)
         }
     }
 
-    if (hasEnv("FOAM_ABORT"))
-    {
-        Perr<< nl << *this << nl
-            << "\nFOAM aborting (FOAM_ABORT set)\n" << endl;
-        printStack(Perr);
-        std::abort();
-    }
-    else if (throwExceptions_)
+    if (throwing_ && !isAbort)
     {
         // Make a copy of the error to throw
         error errorException(*this);
@@ -255,13 +217,20 @@ void Foam::error::exitOrAbort(const int errNo, const bool isAbort)
 
         throw errorException;
     }
+    else if (hasEnv("FOAM_ABORT"))
+    {
+        Perr<< nl << *this << nl
+            << "\nFOAM aborting (FOAM_ABORT set)\n" << endl;
+        error::printStack(Perr);
+        std::abort();
+    }
     else if (Pstream::parRun())
     {
         if (isAbort)
         {
             Perr<< nl << *this << nl
                 << "\nFOAM parallel run aborting\n" << endl;
-            printStack(Perr);
+            error::printStack(Perr);
             Pstream::abort();
         }
         else
@@ -277,7 +246,7 @@ void Foam::error::exitOrAbort(const int errNo, const bool isAbort)
         {
             Perr<< nl << *this << nl
                 << "\nFOAM aborting\n" << endl;
-            printStack(Perr);
+            error::printStack(Perr);
 
             #ifdef _WIN32
             std::exit(1);  // Prefer exit() to avoid unnecessary warnings
@@ -295,9 +264,23 @@ void Foam::error::exitOrAbort(const int errNo, const bool isAbort)
 }
 
 
+// * * * * * * * * * * * * * * * Member Functions  * * * * * * * * * * * * * //
+
+Foam::string Foam::error::message() const
+{
+    return messageStreamPtr_->str();
+}
+
+
+void Foam::error::clear() const
+{
+    return messageStreamPtr_->reset();
+}
+
+
 void Foam::error::exit(const int errNo)
 {
-    exitOrAbort(errNo, hasEnv("FOAM_ABORT"));
+    exitOrAbort(errNo, false);
 }
 
 

src/OpenFOAM/db/error/error.H

@@ -45,6 +45,11 @@ Usage
 
 SourceFiles
     error.C
+    IOerror.C
+
+SeeAlso
+    Foam::errorManip
+    Foam::errorManipArg
 
 \*---------------------------------------------------------------------------*/
 
@@ -52,6 +57,7 @@ SourceFiles
 #define error_H
 
 #include "messageStream.H"
+#include <memory>
 
 // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
 
@@ -80,8 +86,8 @@ protected:
         string functionName_;
         string sourceFileName_;
         label sourceFileLineNumber_;
-        bool throwExceptions_;
-        OStringStream* messageStreamPtr_;
+        bool throwing_;
+        std::unique_ptr<OStringStream> messageStreamPtr_;
 
 
 public:
@@ -138,15 +144,15 @@ public:
         //- Return the current exception throwing (on or off)
         bool throwing() const
         {
-            return throwExceptions_;
+            return throwing_;
         }
 
         //- Activate/deactivate exception throwing
         //  \return the previous throwing state
         inline bool throwExceptions(bool doThrow)
         {
-            const bool prev = throwExceptions_;
-            throwExceptions_ = doThrow;
+            const bool prev = throwing_;
+            throwing_ = doThrow;
             return prev;
         }
 

src/OpenFOAM/db/error/errorManip.H

@@ -135,17 +135,17 @@ exit(error& err, const int errNo = 1)
 }
 
 
-inline errorManip<error>
-abort(error& err)
+inline errorManipArg<IOerror, int>
+exit(IOerror& err, const int errNo = 1)
 {
-    return errorManip<error>(&error::abort, err);
+    return errorManipArg<IOerror, int>(&IOerror::exit, err, errNo);
 }
 
 
-inline errorManipArg<IOerror, int>
-exit(IOerror& err, const int errNo = 1)
+inline errorManip<error>
+abort(error& err)
 {
-    return errorManipArg<IOerror, int>(&IOerror::exit, err, errNo);
+    return errorManip<error>(&error::abort, err);
 }