WIP: Add support for Windows

Add support for building and testing on Windows OS
in a consistent manner to Linux and macOS.
Repository URL and tag are specified in a shared
configuration file (SITK_CONFIG) which is used
by both the configure and configure.win scripts.
Testing is performed in CircleCI as it offers a
more powerful build machine under the free plan.

Co-authored-by: Artur-man <artur-man@hotmail.com>

Author: zivy

.circleci/config.yml

@@ -18,6 +18,12 @@ executors:
     environment:
       RUNNER_OS: macos
     resource_class: m4pro.medium
+  windows:
+    machine:
+      image: windows-server-2022-gui:current
+    environment:
+      RUNNER_OS: windows
+    resource_class: windows.large
 
 jobs:
   r-build:
@@ -32,8 +38,12 @@ jobs:
     steps:
       - checkout
       - run:
-          name: Set environment
+          name: Set library for default R package installation
           command: |
+            # All packages will be installed into the directory
+            # referenced by the R_LIBS environment variable.
+            mkdir -p $HOME/Rlibs
+            ls -la ${R_LIBS}
             echo "export R_LIBS=$HOME/Rlibs" >> $BASH_ENV
       - run:
           name: Install R << parameters.r-version >>
@@ -44,18 +54,17 @@ jobs:
               brew tap r-lib/rig
               brew install --cask rig
               rig add $R_VERSION
-              # on macOS the R package is installed into a MAJOR.MINOR directory
-              # the PATCH is ignored (only one patch version supported) the
-              # architecture is added as a suffix (arm64, x86_64) to allow for
-              # installations to coexist
-              rig default "${R_VERSION%.*}-arm64"
             elif [ "$RUNNER_OS" == "linux" ]; then
               `which sudo` curl -L https://rig.r-pkg.org/deb/rig.gpg -o /etc/apt/trusted.gpg.d/rig.gpg
               `which sudo` sh -c 'echo "deb http://rig.r-pkg.org/deb rig main" > /etc/apt/sources.list.d/rig.list'
               `which sudo` apt update
               `which sudo` apt install r-rig
               sudo rig add $R_VERSION
-              sudo rig default $R_VERSION
+            elif [ "$RUNNER_OS" == "windows" ]; then
+              choco install rig -y
+              export PATH="$PATH:/c/Program Files/rig"
+              rig add $R_VERSION
+              echo "export PATH=\"/c/Program Files/R/R-$R_VERSION/bin:\$PATH\"" >> $BASH_ENV
             fi
       - run:
           name: System Dependencies
@@ -66,25 +75,29 @@ jobs:
               sudo rm -rf /var/lib/apt/lists/*
             elif [ "$RUNNER_OS" == "macos" ]; then
               brew install cmake
+            elif [ "$RUNNER_OS" == "windows" ]; then
+              choco install rtools -y
+              RTOOLS_ROOT=$(ls -d /c/rtools* | head -n 1)
+              echo "export PATH=\"$CMAKE_DIR:$RTOOLS_ROOT/x86_64-w64-mingw32.static.posix/bin:$RTOOLS_ROOT/usr/bin:\$PATH\"" >> $BASH_ENV
             fi
       - run:
           name: Configuration Information
           command: |
-            mkdir -p ${R_LIBS}
-            c++ --version
+            echo $PATH
+            echo "R_LIBS is: ${R_LIBS}"
+            c++ --version || gcc --version || echo "no c++ compiler found"
             cmake --version || echo "cmake not found"
-            which R
-            R --version
+            R --version || echo "R not found"
       - run:
           name: Install R packages
           command: |
-            R -e "install.packages(c('remotes'), lib=c('${R_LIBS}'), repo='https://cloud.r-project.org/')"
+            R -e "install.packages(c('remotes'), repo='https://cloud.r-project.org/')"
       - run:
           name: Build and test
           no_output_timeout: 30m
           command: |
             set -x
-            R -e "remotes::install_git(c('.'), lib=c('${R_LIBS}'), configure.vars=c('MAKEJ=3'))"
+            R -e "remotes::install_git(c('.'), configure.vars=c('MAKEJ=3'))"
 
 workflows:
   r-build-test:
@@ -94,7 +107,7 @@ workflows:
           matrix:
             parameters:
               r-version: ['4.3.1', '4.4.1']
-              os: ["macos-arm"]
+              os: ["macos-arm", "windows"]
           filters:
             branches:
               only:

SITK_CONFIG

@@ -0,0 +1,3 @@
+# SimpleITK configuration shared between configure and configure.win
+export SimpleITKGit=https://github.com/SimpleITK/SimpleITK
+export SITKTAG=v2.5.3

configure

@@ -6,8 +6,9 @@
 #
 # Requires git and cmake
 #
-export SimpleITKGit=https://github.com/SimpleITK/SimpleITK
-export SITKTAG=v2.5.3
+
+# Load shared configuration for all OS (SimpleITKrepository URL and tag)
+source "$(dirname "$0")/SITK_CONFIG"
 
 export PKGBASED=$(pwd)
 echo ${PKGBASED}

configure.win

@@ -0,0 +1,91 @@
+#!/usr/bin/env sh
+set -e
+
+# --- Settings ---
+# Load shared configuration for all OS (SimpleITK repository URL and tag)
+. "$(dirname "$0")/SITK_CONFIG"
+
+PKGBASED=$(pwd)
+echo "$PKGBASED"
+
+# --- Check R_HOME ---
+if [ -z "$R_HOME" ]; then
+  echo "Environment variable \"R_HOME\" is not set!" 1>&2
+  exit 1
+fi
+
+# Use Rscript on Windows
+RCALL="${R_HOME}/bin/Rscript.exe"
+export RCALL
+
+# --- Build location: short path to avoid ITK limit ---
+BUILDDIR="C:/bld"
+echo "Using short build directory: $BUILDDIR"
+mkdir -p "$BUILDDIR"
+
+# Pull compiler flags from R (optional but kept for parity)
+CC="$("${R_HOME}/bin/R.exe" CMD config CC)"
+CXX="$("${R_HOME}/bin/R.exe" CMD config CXX)"
+CFLAGS="$("${R_HOME}/bin/R.exe" CMD config CFLAGS)"
+CXXFLAGS="$("${R_HOME}/bin/R.exe" CMD config CXX11FLAGS)"
+CPPFLAGS="$("${R_HOME}/bin/R.exe" CMD config CPPFLAGS)"
+export CC CXX CFLAGS CXXFLAGS CPPFLAGS
+
+# Parallelism (default 1 if not provided)
+: "${MAKEJ:=1}"
+export MAKEJ
+
+# --- Build in SITK directory ---
+(
+  cd "$BUILDDIR"
+
+  if [ ! -d SimpleITK ]; then
+    git clone "$SimpleITKGit"
+    cd SimpleITK
+    git checkout "$SITKTAG"
+  else
+    cd SimpleITK
+    git fetch --tags
+    git checkout "$SITKTAG"
+  fi
+
+  SITK_SRC="$(pwd)"
+
+  mkdir -p ../Build
+  cd ../Build
+
+  echo "Path:"
+  echo $PWD
+  
+  # Configure with MinGW Makefiles (Rtools toolchain)
+  cmake -G "MinGW Makefiles" \
+    -DWRAP_DEFAULT=OFF \
+    -DWRAP_R=ON \
+    -DSimpleITK_BUILD_DISTRIBUTE=ON \
+    -DBUILD_EXAMPLES=OFF \
+    -DBUILD_TESTING=OFF \
+    -DITK_SKIP_PATH_LENGTH_CHECK=ON \
+    -DCMAKE_BUILD_TYPE=MinSizeRel \
+    -DITK_USE_BUILD_DIR:BOOL=ON \
+    ${ADDITIONAL_SITK_MODULES} \
+    "${BUILDDIR}/SimpleITK/SuperBuild/"
+
+  echo "Parallel build using -j${MAKEJ}"
+  echo $PWD
+  # Build the specific target with parallel jobs
+  cmake --build . --target SimpleITK-build -- -j"${MAKEJ}"
+
+  # Remove ITK-build to save space (if present)
+  [ -d ITK-build ] && rm -rf ITK-build
+
+  # Move wrapped R package into the package root using R
+  "${RCALL}" -f "${PKGBASED}/sitkmove.R" --args \
+    "SimpleITK-build/Wrapping/R/Packaging/SimpleITK" \
+    "${PKGBASED}"
+  
+  echo "directories:"
+  echo $(ls)
+  
+  echo "Path:"
+  echo $PWD
+)