Techdocs for build system developers

The (planned) GitHub repository structure can be found here, and this document explains the layout of the different components and the overall build process.

File System Layout

The top level folder subsequently called OPENCMISS_ROOT is the base folder for the build environment. Its subfolders are as follows:

build/                                       # Root for all build trees
   [arch-dir-short/]mpi/                     # Root for local MPI builds
      openmpi
      mpich
   [arch-dir/]                               # Architecture path including toolchain, mpi, multithreading, ...
      blas[/release|/debug/|...]
      ...
      petsc[/release/|/debug|...]            # The build type is a sub-folder of the component to be consistent with Windows
      iron[/release/|/debug|...]
      zinc[/release/|/debug|...]
      examples[/release/|/debug|...]
   utilities/                                # Architecture-independent build root
      gtest
manage/                                      # The top-level source directory.
   build                                     # The default top-level binary directories
   build_intel
   build_intel_mpi_debug                     # More (examplatory) user-defined top-level build directories
   build_my_naming
src/                                         # Root source directory for all OpenCMISS components
   iron/
   zinc/
   dependencies/                             # Dependency sources are grouped into this folder
      blas/
      ...
      zlib/
   utilities/                                # Utility sources
      cmake/
      git/
   mpi/                                      # Sources for own MPI builds
      openmpi/
      mpich/
examples/                                    # Default folder for OpenCMISS examples
   ex1/
   ex2/
install/                                     # Default OpenCMISS installation root
   [/arch-dir]                               # Architecture path segment
      [/release|/debug|...]                  # The build type if this installation
         bin/                                # Any produced binaries
            cmgui-exe
         lib/                                # All compiled libraries and Fortran modules
            iron.mod
            zinc.a
            blas.a
            zlib.a
         include/                            # The top-level include directory for this installation
            mumps/                           # In order to avoid naming clashes, components with many
            petsc/                           # installed headers are put into subfolders
            ...
   cmake/                                    # CMake-related necessary files
      OpenCMISSExtraFindModules/             # FindXXX.cmake module files to find system components
      OpenCMISSFindModuleWrappers/           # Wrapper files for all FindXXX find module scripts
   utilities/
      gtest/
      cmake/

The main setup project organization

The setup project is the main access point for OpenCMISS builds and shows the following structure (mounted on OPENCMISS_ROOT/manage/):

CMakeLists.txt                               # Main CMake build config file.
Config/                                      # A collection of CMake files regarding the configuration of the build process
CMakeScripts/                                # A collection of scripts performing a specific task. Merely created for tidyness and separation of concerns.
   CMakeCheck.cmake
   OCSetupBuildMacros.cmake
   ...
CMakeFindModuleWrappers/                     # Own wrappers for find_package() calls in OpenCMISS
   FindXXX.cmake
CMakeModules/                                # Own provided MODULE mode search scripts
   FindSUNDIALS.cmake
   ...
Templates/                                   # Files that are configured at some stage of the configuration or build phase
   OpenCMISSLocalConfig.template.cmake
   ...

Examples structure

Similar to the old build system, the examples available for OpenCMISS are kept separate. Ultimately, all the available examples will be hosted in their own GIT repository, and a central examples repository will collect all working examples for any OpenCMISS release. In the process of conversion, however, there still only exists one global examples repository (initialized with the old examples svn repo) at https://github.com/OpenCMISS-Examples/examples, branch “v1.0”.

The current global project can generate the CMakeLists.txt files automatically (not very clever though) for each example. The detection is done simply via looking if the according folder contains a Makefile file. This is far from ideal, but a quick way to see what’s working and what not.

Key tests

Writing Iron IO routines

For any routine that does not directly belong to the OpenCMISS-Iron API (opencmiss_iron.f90), extra declarations have to be made in order to have the according methods exported to Windows .dll files.

Within the respective source, say test_framework_routines.f90, you need to include:

#include "dllexport.h"

to define the DLL export macro. Within each publicly visible routine, you then need to specify !DLLEXPORT(<routinename>) as a comment inside the routine body, e.g:

SUBROUTINE TEST_FRAMEWORK_ASSERT_EQUALS_INTG(EXPECTED_VALUE,ACTUAL_VALUE,ERR)
 !DLLEXPORT(TEST_FRAMEWORK_ASSERT_EQUALS_INTG)

 !Argument variables
 [...]

Building applications

If you write Fortran code and use MPI, you need to use the following MPI directives:

#ifndef NOMPIMOD
  USE MPI
#endif
[...]
  IMPLICIT NONE
[...]
#ifdef NOMPIMOD
  #include "mpif.h"
#endif

Reasoning: In some cases like Windows/MPICH2 there sometimes is no mpi.mod file. In order to yet make the example work the build system adds the definition ‘NOMPIMOD’, which can be checked and acted to accordingly.