Cross-Compile govips for Windows

README.md

Cross-Compile govips for Windows

Build a govips application for Windows on Linux using Docker, MinGW and MSYSY2. Binaries running native on Windows without WSL.

Setup inspired by:

• https://dh1tw.de/2019/12/cross-compiling-golang-cgo-projects/
• https://github.com/editicalu/msys2-cross/blob/master/Dockerfile

Dockerfile

FROM golang:1.16-alpine as builder-linux

RUN apk add \
  vips-dev \
  gcc \
  musl-dev

RUN mkdir /go/pkg \
  && mkdir /tmp/go-cache \
  && chmod ugo=rwX /go/pkg /tmp/go-cache

ENV GOCACHE=/tmp/go-cache
VOLUME /go/pkg
VOLUME /tmp/go-cache

FROM builder-linux as builder-windows

RUN apk add \
  mingw-w64-gcc \
  pacman

RUN mkdir /usr/share/pacman/keyrings/ \
  && wget "https://raw.githubusercontent.com/msys2/MSYS2-keyring/master/msys2-revoked" -O /usr/share/pacman/keyrings/msys2-revoked \
  && wget "https://raw.githubusercontent.com/msys2/MSYS2-keyring/master/msys2-trusted" -O /usr/share/pacman/keyrings/msys2-trusted \
  && wget "https://raw.githubusercontent.com/msys2/MSYS2-keyring/master/msys2.gpg" -O /usr/share/pacman/keyrings/msys2.gpg \
  && pacman-key --init \
  && pacman-key --populate msys2

RUN echo -e "## msys2.org\\nServer = http://repo.msys2.org/mingw/x86_64\\nServer = https://downloads.sourceforge.net/project/msys2/REPOS/MINGW/x86_64" \
 > /etc/pacman.d/mirrorlist.mingw64

RUN echo -e "\\n\\n[mingw64]\\nInclude = /etc/pacman.d/mirrorlist.mingw64" \
 >> /etc/pacman.conf

RUN pacman --noconfirm -Sy mingw-w64-x86_64-libvips \
  && pacman --noconfirm -Sc

COPY objcopy.sh /usr/local/bin/

ENV GOOS=windows
ENV GOARCH=amd64
ENV CGO_ENABLED=1
ENV CC=x86_64-w64-mingw32-gcc
ENV CXX=x86_64-w64-mingw32-g++
ENV PKG_CONFIG_PATH=/mingw64/lib/pkgconfig

objcopy.sh

#!/bin/bash
set -euo pipefail

src="${1:-}"
dst="${2:-}"

if [[ -z "${src}" ]] || [[ ! -f "${src}" ]] || [[ ! -d "${dst}" ]]; then
  echo "Usage $0 [object file] [destination]"
  echo "Script to copy dynamically linked windows binary with their import dependencies"
  exit 1
fi

deps=( )

stack=( "${src}" )
analyzed=( )

ignore=(
  "KERNEL32.dll"
  "msvcrt.dll"
  "ADVAPI32.dll"
  "SHELL32.dll"
  "USER32.dll"
  "WS2_32.dll"
  "ole32.dll"
  "GDI32.dll"
  "MSIMG32.dll"
  "DNSAPI.dll"
  "IPHLPAPI.DLL"
  "SHLWAPI.dll"
  "USERENV.dll"
  "RPCRT4.dll"
  "USP10.dll"
  "gdiplus.dll"
)

paths=(
  "."
  "/mingw64/bin/"
)

while [[ ${#stack[@]} -gt 0 ]]; do
  dep="${stack[0]}"
  analyzed+=( "${dep}" )
  
  found=false
  for p in "${paths[@]}"; do
    if [[ -f "${p}/${dep}" ]]; then
      dep="$( readlink -f "${p}/${dep}" )"
      found=true
      break
    fi
  done

  if ! $found; then
    echo "Error: Could not locate dependency \"${dep}\"."
    exit 2
  fi

  echo "Analyze \"${dep}\""
  while IFS='' read -r line; do stack+=("${line}"); done < \
    <( comm -13 \
      <( printf "%s\n" "${ignore[@]}" "${analyzed[@]}" "${stack[@]}" | uniq | sort  ) \
      <( objdump --private-headers "${dep}" \
        | sed -n 's/^\s*DLL Name: \(.*\.dll\)$/\1/Ip' \
        | uniq | sort ) )

  deps+=( "${dep}" )
  stack=( "${stack[@]:1}" )
done

cp -uv "${deps[@]}" "${dst}"

echo -e "\nCopied ${#deps[@]} dependencies"