Support Loader/Unloader function for libraries

In discussion with @Lars (and others), to forcibly trigger an unload function prior to closing a library. Uses a framework similar to codedBase dlLibraryTable.patch

Cross-ref EP1197. Patch from Bram.

assigned to @mark

changed the description

mentioned in merge request !309 (closed)

/cc @bram.metsch

changed the description

As I am not allowed to push: in addition to feature-dlLibrary-unloader, I needed the following change:

diff --git a/src/OpenFOAM/db/dynamicLibrary/dlLibraryTable/dlLibraryTable.C b/src/OpenFOAM/db/dynamicLibrary/dlLibraryTable/dlLibraryTable.C
index 5242406..dcab583 100644
--- a/src/OpenFOAM/db/dynamicLibrary/dlLibraryTable/dlLibraryTable.C
+++ b/src/OpenFOAM/db/dynamicLibrary/dlLibraryTable/dlLibraryTable.C
@@ -341,6 +341,15 @@ void* Foam::dlLibraryTable::open
 
     if (ptr)
     {
+#ifdef Foam_exptl_dlLibraryLoaderHooks
+        // Attempt load immediately after open
+        loadHook
+        (
+            ptr,
+            dynamicCode::libraryBaseName(libName),
+            debug // verbosity according to debug
+        );
+#endif
         libPtrs_.append(ptr);
         libNames_.append(libName);
     }

Sure, but just to be clear any of the changes here are currently just a way to exchange information. Won't be making any real code changes until the release is out. The final version will also need to have a different naming mechanism than simply using dynamicCode::libraryBaseName(libName).

Imagine you have some library libmpi.so or libpetsc-1.so that you load. Is it reasonable or safe to execute an mpi(bool) or a petsc-1(bool) function? Probably not.

mentioned in issue #1585 (closed)

mentioned in commit 2811c054

Should be unnecessary after 2811c054 - can revisit if still needed

closed