build: modernize dockerfile, make more reproducible

docker/Dockerfile

@@ -1,26 +1,74 @@
-FROM docker.io/library/debian:stable-slim
+FROM scratch AS zipdeps
+
+ARG CMAKE_VERSION=3.26.6
+ARG NINJA_VERSION=1.12.1
+
+ADD --checksum=sha256:7947618912e2c2f48f987631e29e318e56ccda551a7b65364c8a3f743e719ac5 \
+    https://github.com/itsmattkc/MSVC420/archive/df2c13aad74c094988c6c7e784234c2e778a0e91.zip \
+    msvc.zip
+ADD --checksum=sha256:dc3f535d880d1ffa7cfa86a0eefdc1fc9bf8b9ede59d1deb7a2bb41f0a58d2d4 \
+    https://github.com/Kitware/CMake/releases/download/v$CMAKE_VERSION/cmake-$CMAKE_VERSION-windows-i386.zip \
+    cmake.zip
+ADD --checksum=sha256:f550fec705b6d6ff58f2db3c374c2277a37691678d6aba463adcbb129108467a \
+    https://github.com/ninja-build/ninja/releases/download/v$NINJA_VERSION/ninja-win.zip \
+    ninja.zip
+
+################################################################################
+
+FROM debian:stable-slim
 
 # Gather dependencies
-RUN dpkg --add-architecture i386
-RUN apt-get update -y
-RUN apt-get install git wine wine64 wine32 wget unzip -y
+RUN <<EOF
+dpkg --add-architecture i386
+apt-get update -y
+apt-get install -y --no-install-recommends \
+    libarchive-tools \
+    wine \
+    wine32 \
+    wine64
+EOF
 
 # Silence debug warnings in wine (creates noise during compile)
-RUN export WINEDEBUG=-all
-
-# Set up the wineprefix
+ARG WINEDEBUG=-all
+ARG WINEPREFIX=/root/.wine
 RUN wine wineboot
 
-# Set up MSVC 4.20 and CMake for Windows
-RUN git clone https://github.com/itsmattkc/MSVC420 ~/.wine/drive_c/msvc
-RUN wget https://github.com/Kitware/CMake/releases/download/v3.26.6/cmake-3.26.6-windows-i386.zip
-RUN unzip cmake-3.26.6-windows-i386.zip -d ~/.wine/drive_c
-RUN mv ~/.wine/drive_c/cmake-3.26.6-windows-i386 ~/.wine/drive_c/cmake
-RUN rm cmake-3.26.6-windows-i386.zip
+# extract everything
+RUN --mount=from=zipdeps,target=/zipdeps <<EOF
+extract() {
+    p="$WINEPREFIX/drive_c/$1"
+    dep="/zipdeps/$1.zip"
+    shift
 
-RUN wget https://github.com/ninja-build/ninja/releases/download/v1.12.1/ninja-win.zip
-RUN unzip ninja-win.zip -d ~/.wine/drive_c
-RUN rm ninja-win.zip
+    mkdir -p "$p" && bsdtar -oxvf "$dep" -C "$p" $@
+}
+
+extract cmake --strip-components 1
+extract msvc --strip-components 1
+extract ninja
+EOF
+
+# remove clutter
+RUN <<EOF
+apt-get remove --purge libarchive-tools
+apt-get clean
+rm -rf /var/lib/apt/lists/*
+EOF
+
+# Populate the Windows path inside of the wineprefix
+RUN <<EOF
+setenv() {
+    wine reg ADD 'HKCU\Environment' /v "$1" /d "$2" /f
+    # wine doesn't set it synchronously, server gets cut off by docker if you
+    # don't give it enough time
+    sleep 0.5
+}
+setenv PATH 'C:\msvc\bin;C:\msvc\bin\winnt;C:\cmake\bin;C:\windows\system32;C:\ninja'
+setenv INCLUDE 'C:\msvc\include;C:\msvc\mfc\include'
+setenv LIB 'C:\msvc\lib;C:\msvc\mfc\lib'
+setenv TMP 'Z:\build'
+setenv TEMP 'Z:\build'
+EOF
 
 # Set up entrypoint script to perform the build
 COPY entrypoint.sh entrypoint.sh

docker/build.sh

@@ -48,7 +48,7 @@ trap cleanup EXIT
 mkdir -p result
 rm -rf result/*
 
-if [[ "x${JOBS:-}" == "x" ]]; then
+if [ "x${JOBS:-}" = "x" ]; then
     JOBS=$(nproc)
 fi
 

docker/entrypoint.sh

@@ -1,13 +1,6 @@
 #!/usr/bin/env bash
 
-# Populate the Windows path inside of the wineprefix
-# TODO: This is in here because writing to the registry seems
-# to fail when performed in the Dockerfile itself; investigate
-wine reg ADD 'HKCU\Environment' /v PATH /d 'C:\msvc\bin;C:\msvc\bin\winnt;C:\cmake\bin;C:\windows\system32;C:\' /f
-wine reg ADD 'HKCU\Environment' /v INCLUDE /d 'C:\msvc\include;C:\msvc\mfc\include' /f
-wine reg ADD 'HKCU\Environment' /v LIB /d 'C:\msvc\lib;C:\msvc\mfc\lib' /f
-wine reg ADD 'HKCU\Environment' /v TMP /d 'Z:\build' /f
-wine reg ADD 'HKCU\Environment' /v TEMP /d 'Z:\build' /f
+set -e
 
 # Configure build with CMake
 wine cmake -B build isle -G "Ninja" $CMAKE_FLAGS