Alpine Linux cross-compiler setup script

setup-cross-cc.sh

#!/bin/sh

CTARGET="$1"
if [ -z "$CTARGET" ]; then
	program=$(basename $0)
	echo "usage: $program TARGET_ARCH"
	return 1
fi

# get abuild configurables
[ -e /usr/share/abuild/functions.sh ] || (echo "abuild not found" ; exit 1)

. /usr/share/abuild/functions.sh
[ -z "$CBUILD_ARCH" ] && die "abuild is too old"

# deduce aports directory
[ -z "$APORTSDIR" ] && [[ APORTSDIR=$(realpath $(dirname $0)/../) && \
[ -e "$APORTSDIR/main/build-base" ] || die "Unable to deduce aports base checkout" ]]

APK="apk --root $CBUILDROOT"

msg() {
	local name="${BLUE}bootstrap-${CTARGET_ARCH}${NORMAL}"
	printf "$GREEN>>>${NORMAL} ${name}: %s\n" "$1" >&2
}
err() {
	printf "$RED>>> ERROR${NORMAL}: %s\n" "$*" >&2
}
die() {
	err "$*"
	exit 2
}

if [ ! -d "$CBUILDROOT" ]; then
	msg "Creating sysroot in $CBUILDROOT"
	if [ -z "$PACKAGER_PRIVKEY" ] || [ ! -f "$PACKAGER_PRIVKEY" ]; then
		abuild-keygen -i -a || exit 2
		. ~/.abuild/abuild.conf
	fi

	APK_ROOT_CONF="$CBUILDROOT/etc/apk"
	mkdir -p "$APK_ROOT_CONF/keys"
	cp /etc/apk/repositories "$APK_ROOT_CONF/"
	case $CTARGET_ARCH in # HACK
		armv7) keypath=/usr/share/apk/keys/armhf ;;
		*) keypath=/usr/share/apk/keys/$CTARGET_ARCH ;;
	esac
	cp $keypath/* "$APK_ROOT_CONF/keys/"
	cp $PACKAGER_PRIVKEY.pub "$APK_ROOT_CONF/keys/"
	$APK add --update --initdb --arch $CTARGET_ARCH libc-dev libgcc ||
		die "failed to initialize target APK repository"
fi

msg "Building cross-compiler"
export CBUILD CHOST CTARGET BOOTSTRAP=nobase

# Build and install cross binutils (--with-sysroot)
APKBUILD=$(aports_buildscript binutils) abuild -r ||
	die "failed to build binutils-$CTARGET_ARCH"

# Full cross GCC
EXTRADEPENDS_TARGET="musl musl-dev" \
	LANG_ADA=false LANG_D=false LANG_OBJC=false LANG_GO=false LANG_FORTRAN=false \
	APKBUILD=$(any_buildscript gcc) abuild -r ||
		die "failed to build gcc-$CTARGET_ARCH"

# Cross build-base
APKBUILD=$(aports_buildscript build-base) abuild -r ||
	die "failed to build build-base"

msg "Done"
echo "To install the cross-compiler use 'apk --repository $REPODEST/main --keys-dir ~/.abuild add build-base-$CTARGET_ARCH'"
echo "To build Alpine packages for '$CTARGET_ARCH' use 'CHOST=$CTARGET_ARCH abuild -r'"
echo "To explicitly install cross-build libraries use '$APK add --no-scripts <pkg>'"