ENH: handle 'void' type in IOobject::typeHeaderOk

- can be used in most places where checkType=false is used

ENH: add non-const get() method to HashPtrTable

- allows checking and modification (symmetric with PtrList methods)

STYLE: improve annotations in fileOperations headers

applications/test/HashPtrTable/Make/files

@@ -1,3 +1,3 @@
-Test-HashPtrTable.C
+Test-HashPtrTable.cxx
 
 EXE = $(FOAM_USER_APPBIN)/Test-HashPtrTable

applications/test/HashTable2/Make/files

@@ -1,3 +1,3 @@
-Test-HashTable2.C
+Test-HashTable2.cxx
 
 EXE = $(FOAM_USER_APPBIN)/Test-HashTable2

applications/test/HashTable3/Make/files

@@ -1,3 +1,3 @@
-Test-HashTable3.C
+Test-HashTable3.cxx
 
 EXE = $(FOAM_USER_APPBIN)/Test-HashTable3

applications/test/IOobjectList/Make/files

@@ -1,3 +1,3 @@
-Test-IOobjectList.C
+Test-IOobjectList.cxx
 
 EXE = $(FOAM_USER_APPBIN)/Test-IOobjectList

applications/test/PtrList/Make/files

@@ -1,3 +1,3 @@
-Test-PtrList.C
+Test-PtrList.cxx
 
 EXE = $(FOAM_USER_APPBIN)/Test-PtrList

src/OpenFOAM/containers/HashTables/HashPtrTable/HashPtrTable.H

@@ -149,6 +149,10 @@ public:
         //- if the key does not exist in the table.
         inline const T* get(const Key& key) const;
 
+        //- Return pointer associated with given entry or a nullptr
+        //- if the key does not exist in the table.
+        inline T* get(const Key& key);
+
 
     // Edit
 
@@ -234,7 +238,9 @@ public:
         inline bool emplace(const Key& key, Args&&... args);
 
         //- Emplace set an entry, overwriting any existing entries.
-        //  \return Reference to the new element.
+        //  \param key - the location to set
+        //  \param args arguments to forward to the constructor of the element
+        //  \return reference to the new element.
         template<class... Args>
         inline T& emplace_set(const Key& key, Args&&... args);
 

src/OpenFOAM/containers/HashTables/HashPtrTable/HashPtrTableI.H

@@ -5,7 +5,7 @@
     \\  /    A nd           | www.openfoam.com
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
-    Copyright (C) 2018-2023 OpenCFD Ltd.
+    Copyright (C) 2018-2025 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -57,6 +57,19 @@ inline const T* Foam::HashPtrTable<T, Key, Hash>::get(const Key& key) const
 }
 
 
+template<class T, class Key, class Hash>
+inline T* Foam::HashPtrTable<T, Key, Hash>::get(const Key& key)
+{
+    // Like lookup() with a nullptr + const_cast
+    iterator iter(this->find(key));
+    if (iter.good())
+    {
+        return iter.val();
+    }
+    return nullptr;
+}
+
+
 template<class T, class Key, class Hash>
 template<class... Args>
 inline bool Foam::HashPtrTable<T, Key, Hash>::emplace

src/OpenFOAM/db/IOobject/IOobject.H

@@ -537,14 +537,15 @@ public:
         //- True if headerClassName() is non-empty (after reading)
         inline bool hasHeaderClass() const noexcept;
 
+        //- Check if headerClassName() equals the expected type.
+        //- Always true if the expected type is empty.
+        inline bool isHeaderClass(const word& expectedType) const;
+
         //- Check if headerClassName() equals Type::typeName
+        //- Always true for a \c void type.
         template<class Type>
         inline bool isHeaderClass() const;
 
-        //- Same as isHeaderClass()
-        template<class Type>
-        bool isHeaderClassName() const { return isHeaderClass<Type>(); }
-
 
     // Meta-data
 
@@ -611,20 +612,18 @@ public:
         fileName objectRelPath() const;
 
         //- Redirect to fileHandler filePath, searching locally.
-        //  When search is false, simply use the current instance,
-        //  otherwise search previous instances.
         fileName localFilePath
         (
             const word& typeName,
+            //! False: use current instance; True: search previous instances
             const bool search=true
         ) const;
 
         //- Redirect to fileHandler filePath, searching up if in parallel.
-        //  When search is false, simply use the current instance,
-        //  otherwise search previous instances.
         fileName globalFilePath
         (
             const word& typeName,
+            //! False: use current instance; True: search previous instances
             const bool search=true
         ) const;
 
@@ -645,17 +644,29 @@ public:
         bool readHeader(dictionary& headerDict, Istream& is);
 
         //- Read header (respects is_globalIOobject trait) and check its info.
+        //- A \c void type suppresses trait and type-name checks.
         template<class Type>
         bool typeHeaderOk
         (
             //! Check headerClassName against the type-name
-            const bool checkType = true,
+            [[maybe_unused]] const bool checkType = true,
             //! Also search previous instances if not found at current instance
             const bool search = true,
             //! Report any check-type failures
             const bool verbose = true
         );
 
+        //- Forwards to single-parameter version with the specified search type.
+        //- A \c void type suppresses trait and type-name checks.
+        template<class Type, bool Searching>
+        bool typeHeaderOk
+        (
+            //! Check headerClassName against the type-name
+            const bool checkType = true,
+            //! Report any check-type failures
+            const bool verbose = true
+        );
+
         //- Call localFilePath or globalFilePath for given type
         //- depending on its is_globalIOobject trait.
         template<class Type>
@@ -718,19 +729,16 @@ public:
 
         //- Copy assignment, copies all values (except the registry)
         void operator=(const IOobject& io);
+
+
+    // Housekeeping
+
+        //- Same as isHeaderClass()
+        template<class Type>
+        bool isHeaderClassName() const { return isHeaderClass<Type>(); }
 };
 
 
-// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
-
-//- Specialization for \c void always returns true (no headerClassName check).
-template<>
-inline bool IOobject::isHeaderClass<void>() const
-{
-    return true;
-}
-
-
 // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
 
 } // End namespace Foam

src/OpenFOAM/db/IOobject/IOobjectI.H

@@ -261,10 +261,23 @@ inline bool Foam::IOobject::hasHeaderClass() const noexcept
 }
 
 
+inline bool Foam::IOobject::isHeaderClass(const word& expectedType) const
+{
+    return (expectedType.empty() || (expectedType == headerClassName_));
+}
+
+
 template<class Type>
 inline bool Foam::IOobject::isHeaderClass() const
 {
-    return (Type::typeName == headerClassName_);
+    if constexpr (std::is_void_v<Type>)
+    {
+        return true;
+    }
+    else
+    {
+        return (Type::typeName == headerClassName_);
+    }
 }
 
 

src/OpenFOAM/db/IOobject/IOobjectReadHeader.C

@@ -215,17 +215,13 @@ bool Foam::IOobject::readAndCheckHeader
             ok = handler.readHeader(*this, fName, typeName);
             UPstream::parRun(oldParRun);
 
-            if
-            (
-                ok && checkType
-             && !typeName.empty() && headerClassName_ != typeName
-            )
+            if (ok && checkType && !isHeaderClass(typeName))
             {
                 ok = false;
                 if (verbose)
                 {
                     WarningInFunction
-                        << "Unexpected class name \"" << headerClassName_
+                        << "Unexpected class name \"" << headerClassName()
                         << "\" expected \"" << typeName
                         << "\" when reading " << fName << endl;
                 }
@@ -251,17 +247,13 @@ bool Foam::IOobject::readAndCheckHeader
         );
         ok = handler.readHeader(*this, fName, typeName);
 
-        if
-        (
-            ok && checkType
-         && !typeName.empty() && headerClassName_ != typeName
-        )
+        if (ok && checkType && !isHeaderClass(typeName))
         {
             ok = false;
             if (verbose)
             {
                 WarningInFunction
-                    << "Unexpected class name \"" << headerClassName_
+                    << "Unexpected class name \"" << headerClassName()
                     << "\" expected \"" << typeName
                     << "\" when reading " << fName << endl;
             }

src/OpenFOAM/db/IOobject/IOobjectTemplates.C

@@ -42,14 +42,35 @@ bool Foam::IOobject::typeHeaderOk
     const bool verbose
 )
 {
-    return readAndCheckHeader
-    (
-        is_globalIOobject<Type>::value,
-        Type::typeName,
-        checkType,
-        search,
-        verbose
-    );
+    if constexpr (std::is_void_v<Type>)
+    {
+        return readAndCheckHeader
+        (
+            false,      // isGlobal (false)
+            word::null, // typeName (n/a)
+            false,      // checkType (false)
+            search,
+            verbose
+        );
+    }
+    else
+    {
+        return readAndCheckHeader
+        (
+            is_globalIOobject<Type>::value,
+            Type::typeName,
+            checkType,
+            search,
+            verbose
+        );
+    }
+}
+
+
+template<class Type, bool Searching>
+bool Foam::IOobject::typeHeaderOk(const bool checkType, const bool verbose)
+{
+    return typeHeaderOk<Type>(checkType, Searching, verbose);
 }
 
 

src/OpenFOAM/db/IOstreams/dummy/dummyISstream.H

@@ -6,7 +6,7 @@
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
     Copyright (C) 2017 OpenFOAM Foundation
-    Copyright (C) 2019-2023 OpenCFD Ltd.
+    Copyright (C) 2019-2025 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -32,7 +32,7 @@ Description
     taking an Istream or ISstream. Aborts at any attempt to read from it.
 
 Note
-    The inheritance from an empty IStringStream is solely for convenience
+    The inheritance from an empty ICharStream is solely for convenience
     of implementation and should not be relied upon.
 
 SourceFiles
@@ -43,7 +43,8 @@ SourceFiles
 #ifndef Foam_dummyISstream_H
 #define Foam_dummyISstream_H
 
-#include "StringStream.H"
+#include "autoPtr.H"
+#include "SpanStream.H"
 
 // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
 
@@ -56,7 +57,7 @@ namespace Foam
 
 class dummyISstream
 :
-    public IStringStream
+    public ICharStream
 {
 public:
 
@@ -69,6 +70,15 @@ public:
         virtual ~dummyISstream() = default;
 
 
+    // Factory Methods
+
+        //- Return a dummyISstream
+        static autoPtr<ISstream> New()
+        {
+            return autoPtr<ISstream>(new dummyISstream());
+        }
+
+
     // Member Functions
 
     // Stream-state

src/OpenFOAM/global/fileOperations/collatedFileOperation/collatedFileOperation.H

@@ -147,7 +147,7 @@ public:
             virtual fileName objectPath
             (
                 const IOobject& io,
-                const word& typeName
+                const word& typeName  //!< currently unused
             ) const;
 
             //- Writes a regIOobject (so header, contents and divider).

src/OpenFOAM/global/fileOperations/dummyFileOperation/dummyFileOperation.C

@@ -327,7 +327,7 @@ Foam::fileOperations::dummyFileOperation::readStream
 ) const
 {
     NotImplemented;
-    return autoPtr<ISstream>(new dummyISstream());
+    return dummyISstream::New();
 }
 
 
@@ -351,7 +351,7 @@ Foam::fileOperations::dummyFileOperation::NewIFstream
 ) const
 {
     NotImplemented;
-    return autoPtr<ISstream>(new dummyISstream());
+    return dummyISstream::New();
 }
 
 

src/OpenFOAM/global/fileOperations/dummyFileOperation/dummyFileOperation.H

@@ -203,18 +203,21 @@ public:
 
         // (reg)IOobject functionality
 
-            //- Search for an object. checkGlobal
+            //- Search for an object
             virtual fileName filePath
             (
+                //! also check undecomposed case
                 const bool checkGlobal,
                 const IOobject& io,
+                //! The wanted object typeName [optional, likely unused]
                 const word& typeName,
                 const bool search
             ) const;
 
-            //- Search for a directory. checkGlobal
+            //- Search for a directory
             virtual fileName dirPath
             (
+                //! also check undecomposed case
                 const bool checkGlobal,
                 const IOobject& io,
                 const bool search
@@ -234,7 +237,7 @@ public:
             (
                 IOobject&,
                 const fileName&,
-                const word& typeName
+                const word& typeName  //!< currently unused
             ) const;
 
             //- Reads header for regIOobject and returns an ISstream
@@ -243,7 +246,7 @@ public:
             (
                 regIOobject&,
                 const fileName&,
-                const word& typeName,
+                const word& typeName,  //!< currently unused
                 const bool readOnProc = true
             ) const;
 
@@ -253,7 +256,7 @@ public:
                 regIOobject&,
                 const bool masterOnly,
                 const IOstreamOption::streamFormat format,
-                const word& typeName
+                const word& typeName  //!< forwards to regIOobject
             ) const;
 
             //- Generate an ISstream that reads a file

src/OpenFOAM/global/fileOperations/fileOperation/fileOperation.C

@@ -28,7 +28,6 @@ License
 
 #include "fileOperation.H"
 #include "objectRegistry.H"
-#include "labelIOList.H"
 #include "registerSwitch.H"
 #include "stringOps.H"
 #include "Time.H"
@@ -728,7 +727,7 @@ bool Foam::fileOperation::exists(IOobject& io) const
         (
             isFile(objPath)
             // object with local scope
-         && io.typeHeaderOk<labelIOList>(false)
+         && io.typeHeaderOk<regIOobject>(false)
         );
     }
 
@@ -750,7 +749,7 @@ bool Foam::fileOperation::exists(IOobject& io) const
                 (
                     isFile(originalPath)
                     // object with local scope
-                 && io.typeHeaderOk<labelIOList>(false)
+                 && io.typeHeaderOk<regIOobject>(false)
                 );
             }
         }

src/OpenFOAM/global/fileOperations/fileOperation/fileOperation.H

@@ -684,27 +684,28 @@ public:
         // (reg)IOobject functionality
 
             //- Generate disk file name for object. Opposite of filePath.
-            //  Optional wanted typeName.
             virtual fileName objectPath
             (
                 const IOobject& io,
+                //! The wanted object typeName [optional, likely unused]
                 const word& typeName
             ) const;
 
-            //- Search for an object. checkGlobal : also check undecomposed case
-            //  Optional wanted typeName.
+            //- Search for an object
             virtual fileName filePath
             (
+                //! also check undecomposed case
                 const bool checkGlobal,
                 const IOobject&,
+                //! The wanted object typeName [optional, likely unused]
                 const word& typeName,
                 const bool search = true
             ) const = 0;
 
-            //- Search for a directory. checkGlobal : also check undecomposed
-            //  case
+            //- Search for a directory
             virtual fileName dirPath
             (
+                //! also check undecomposed case
                 const bool checkGlobal,
                 const IOobject& io,
                 const bool search = true
@@ -724,7 +725,7 @@ public:
             (
                 IOobject&,
                 const fileName&,
-                const word& typeName
+                const word& typeName  //!< frequently unused?
             ) const = 0;
 
             //- Reads header for regIOobject and returns an ISstream
@@ -733,7 +734,7 @@ public:
             (
                 regIOobject&,
                 const fileName&,
-                const word& typeName,
+                const word& typeName,  //!< frequently unused?
                 const bool readOnProc = true
             ) const = 0;
 
@@ -742,7 +743,9 @@ public:
             (
                 regIOobject&,
                 const bool masterOnly,
+                //! The format for parallel send/recv
                 const IOstreamOption::streamFormat format,
+                //! forwards to regIOobject
                 const word& typeName
             ) const = 0;
 

src/OpenFOAM/global/fileOperations/masterUncollatedFileOperation/masterUncollatedFileOperation.C

@@ -586,7 +586,7 @@ Foam::fileOperations::masterUncollatedFileOperation::read
         }
         else
         {
-            isPtr.reset(new dummyISstream());
+            return dummyISstream::New();
         }
     }
 

src/OpenFOAM/global/fileOperations/masterUncollatedFileOperation/masterUncollatedFileOperation.H

@@ -411,20 +411,20 @@ protected:
 
         //- Search (locally!) for object; return info on how it was found.
         //  Does not do any parallel communication.
-        //    checkGlobal : also check undecomposed case
-        //    isFile      : true:check for file  false:check for directory
-        // searchType    : how was found
-        // processorsDir : name of processor directory
-        // instance      : instance
         virtual fileName filePathInfo
         (
+            //! also check undecomposed case
             const bool checkGlobal,
+            //! True (check for file), False (check for directory)
             const bool isFile,
             const IOobject& io,
             const dirIndexList& pDirs,
             const bool search,
+            //! [out] how was found
             pathType& searchType,
+            //! [out] name of processor directory
             word& processorsDir,
+            //! [out] instance
             word& instance
         ) const;
 
@@ -623,19 +623,20 @@ public:
 
         // (reg)IOobject functinality
 
-            //- Search for an object. checkGlobal : also check undecomposed case
+            //- Search for an object
             virtual fileName filePath
             (
+                //! also check undecomposed case
                 const bool checkGlobal,
                 const IOobject& io,
-                const word& typeName,
+                const word& typeName,  //!< currently unused
                 const bool search
             ) const;
 
-            //- Search for a directory. checkGlobal : also check undecomposed
-            //  case
+            //- Search for a directory
             virtual fileName dirPath
             (
+                //! also check undecomposed case
                 const bool checkGlobal,
                 const IOobject& io,
                 const bool search
@@ -655,7 +656,7 @@ public:
             (
                 IOobject&,
                 const fileName&,
-                const word& typeName
+                const word& typeName  //!< currently unused
             ) const;
 
             //- Reads header for regIOobject and returns an ISstream
@@ -664,7 +665,7 @@ public:
             (
                 regIOobject&,
                 const fileName&,
-                const word& typeName,
+                const word& typeName,  //!< currently unused
                 const bool readOnProc = true
             ) const;
 
@@ -673,7 +674,9 @@ public:
             (
                 regIOobject&,
                 const bool masterOnly,
+                //! The format for parallel send/recv
                 const IOstreamOption::streamFormat format,
+                //! forwards to regIOobject
                 const word& typeName
             ) const;
 

src/OpenFOAM/global/fileOperations/uncollatedFileOperation/uncollatedFileOperation.C

@@ -621,7 +621,7 @@ Foam::fileOperations::uncollatedFileOperation::readStream
 {
     if (!readOnProc)
     {
-        return autoPtr<ISstream>(new dummyISstream());
+        return dummyISstream::New();
     }
 
     if (fName.empty())

src/OpenFOAM/global/fileOperations/uncollatedFileOperation/uncollatedFileOperation.H

@@ -243,19 +243,20 @@ public:
 
         // (reg)IOobject functionality
 
-            //- Search for an object. checkGlobal : also check undecomposed case
+            //- Search for an object
             virtual fileName filePath
             (
+                //! also check undecomposed case
                 const bool checkGlobal,
                 const IOobject& io,
-                const word& typeName,
+                const word& typeName,  //!< currently unused
                 const bool search
             ) const;
 
-            //- Search for a directory. checkGlobal : also check undecomposed
-            //  case
+            //- Search for a directory
             virtual fileName dirPath
             (
+                //! also check undecomposed case
                 const bool checkGlobal,
                 const IOobject& io,
                 const bool search
@@ -275,16 +276,16 @@ public:
             (
                 IOobject&,
                 const fileName&,
-                const word& typeName
+                const word& typeName  //!< currently only for debug info
             ) const;
 
             //- Reads header for regIOobject and returns an ISstream
-            //  to read the contents.
+            //- to read the contents.
             virtual autoPtr<ISstream> readStream
             (
                 regIOobject&,
                 const fileName&,
-                const word& typeName,
+                const word& typeName,  //!< currently unused
                 const bool readOnProc = true
             ) const;
 
@@ -293,7 +294,9 @@ public:
             (
                 regIOobject&,
                 const bool masterOnly,
+                //! The format for parallel send/recv
                 const IOstreamOption::streamFormat format,
+                //! forwards to regIOobject
                 const word& typeName
             ) const;
 

src/OpenFOAM/meshes/polyMesh/zones/ZoneMesh/cellZoneMesh.H

@@ -28,8 +28,8 @@ Description
 
 \*---------------------------------------------------------------------------*/
 
-#ifndef cellZoneMesh_H
-#define cellZoneMesh_H
+#ifndef Foam_cellZoneMesh_H
+#define Foam_cellZoneMesh_H
 
 #include "ZoneMesh.H"
 #include "cellZone.H"

src/OpenFOAM/meshes/polyMesh/zones/ZoneMesh/cellZoneMeshFwd.H

@@ -27,12 +27,12 @@ Typedef
     Foam::cellZoneMesh
 
 Description
-    A ZoneMesh with the type cellZone
+    A ZoneMesh with cellZone content on a polyMesh
 
 \*---------------------------------------------------------------------------*/
 
-#ifndef cellZoneMeshFwd_H
-#define cellZoneMeshFwd_H
+#ifndef Foam_cellZoneMeshFwd_H
+#define Foam_cellZoneMeshFwd_H
 
 // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
 

src/OpenFOAM/meshes/polyMesh/zones/ZoneMesh/faceZoneMesh.H

@@ -28,8 +28,8 @@ Description
 
 \*---------------------------------------------------------------------------*/
 
-#ifndef faceZoneMesh_H
-#define faceZoneMesh_H
+#ifndef Foam_faceZoneMesh_H
+#define Foam_faceZoneMesh_H
 
 #include "ZoneMesh.H"
 #include "faceZone.H"

src/OpenFOAM/meshes/polyMesh/zones/ZoneMesh/faceZoneMeshFwd.H

@@ -27,12 +27,12 @@ Typedef
     Foam::faceZoneMesh
 
 Description
-    A ZoneMesh with the type faceZone
+    A ZoneMesh with faceZone content on a polyMesh
 
 \*---------------------------------------------------------------------------*/
 
-#ifndef faceZoneMeshFwd_H
-#define faceZoneMeshFwd_H
+#ifndef Foam_faceZoneMeshFwd_H
+#define Foam_faceZoneMeshFwd_H
 
 // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
 

src/OpenFOAM/meshes/polyMesh/zones/ZoneMesh/pointZoneMesh.H

@@ -28,8 +28,8 @@ Description
 
 \*---------------------------------------------------------------------------*/
 
-#ifndef pointZoneMesh_H
-#define pointZoneMesh_H
+#ifndef Foam_pointZoneMesh_H
+#define Foam_pointZoneMesh_H
 
 #include "ZoneMesh.H"
 #include "pointZone.H"

src/OpenFOAM/meshes/polyMesh/zones/ZoneMesh/pointZoneMeshFwd.H

@@ -27,12 +27,12 @@ Typedef
     Foam::pointZoneMesh
 
 Description
-    A ZoneMesh with the type pointZone
+    A ZoneMesh with pointZone content on a polyMesh
 
 \*---------------------------------------------------------------------------*/
 
-#ifndef pointZoneMeshFwd_H
-#define pointZoneMeshFwd_H
+#ifndef Foam_pointZoneMeshFwd_H
+#define Foam_pointZoneMeshFwd_H
 
 // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
 

src/meshTools/topoSet/cellSources/fieldToCell/fieldToCell.C

@@ -195,7 +195,7 @@ void Foam::fieldToCell::applyToSet
             << "Cannot read field " << fieldName_
             << " from time " << mesh().time().timeName() << endl;
     }
-    else if ("volScalarField" == fieldObject.headerClassName())
+    else if (fieldObject.isHeaderClass("volScalarField"))
     {
         // Note: cannot use volScalarField::typeName since that would
         //    introduce linkage problems (finiteVolume needs meshTools)
@@ -209,7 +209,7 @@ void Foam::fieldToCell::applyToSet
 
         applyToSet(action, internalVals, set);
     }
-    else if ("volVectorField" == fieldObject.headerClassName())
+    else if (fieldObject.isHeaderClass("volVectorField"))
     {
         // Note: cannot use volVectorField::typeName since that would
         //    introduce linkage problems (finiteVolume needs meshTools)