Fortran header

[chiaraMaHe]

The header with the first basic functions for the Fortran interface were added and it was added to the Makefile.

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As a reviewer please read through all the code lines and make sure that the code is fully understood, bug free, well-documented and well-structured.

General

• [ ] The reviewer executed the new code features at least once and checked the results manually

• [ ] The code follows the t8code coding guidelines

• [ ] New source/header files are properly added to the Makefiles

• [ ] The code is well documented

• [ ] All function declarations, structs/classes and their members have a proper doxygen documentation

• [ ] All new algorithms and data structures are sufficiently optimal in terms of memory and runtime (If this should be merged, but there is still potential for optimization, create a new issue)

Tests

• [ ] The code is covered in an existing or new test case using Google Test

Github action

• [ ] The code compiles without warning in debugging and release mode, with and without MPI (this should be executed automatically in a github action)

• [ ] All tests pass (in various configurations, this should be executed automatically in a github action)

  If the Pull request introduces code that is not covered by the github action (for example coupling with a new library):

  • [ ] Should this use case be added to the github action?
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Scripts and Wiki

• [ ] If a new directory with source-files is added, it must be covered by the script/find_all_source_files.scp to check the indentation of these files.
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Licence

• [ ] The author added a BSD statement to doc/ (or already has one)

[sandro-elsweijer]

I do not know how we will finally split the C and CPP interface, but we will need a new folder structure for this. Maybe we can do it like here and have a separate API folder for every API? https://gitlab.onelab.info/gmsh/gmsh Then we could also add the Julia api as an optional submodule. We could do the same with the Fortran interface.

[chiaraMaHe]

I am not able to test the functionality, since I do not have a clue of Fortran, but it looks alright. Btw, how does this work? These are just declarations, where are the actual definitions? And can Fortran just link to a c header file, or where are the Fortran files?

This is only the c header file, that will be imported into a c file, which defines functions that are needed by the f90 file. It makes it easier because you sometimes need to pass the pointer instead of the value (Ccomm). The c-file and the f90 file will follow in the upcoming PRs