mkosi: Make scripts more generic

We might want to run the build scripts outside of mkosi as well at
some point, e.g. to build an rpm after booting the image, so let's
make them more generic by using /usr/lib/os-release to figure out
which pkg specs we should use instead of $PKG_SUBDIR. To make ubuntu
use the debian pkg spec, we add a symlink pkg/ubuntu which points to
debian/ in the same directory.

mkosi.images/system/mkosi.conf.d/10-arch/mkosi.build.chroot

@@ -2,17 +2,20 @@
 # SPDX-License-Identifier: LGPL-2.1-or-later
 set -ex
 
-if [ ! -f "pkg/$PKG_SUBDIR/PKGBUILD" ]; then
-    echo "PKGBUILD not found at pkg/$PKG_SUBDIR/PKGBUILD, run mkosi once with -ff to make sure the PKGBUILD is cloned" >&2
+# shellcheck source=/dev/null
+. /usr/lib/os-release
+
+if [ ! -f "pkg/$ID/PKGBUILD" ]; then
+    echo "PKGBUILD not found at pkg/$ID/PKGBUILD, run mkosi once with -ff to make sure the PKGBUILD is cloned" >&2
     exit 1
 fi
 
 # We can't configure the source or build directory so we use bind mounts instead to make sure they are in the
 # expected locations.
-mount --mkdir --bind "$SRCDIR" "pkg/$PKG_SUBDIR/systemd-stable/"
-mount --mkdir --bind "$BUILDDIR" "pkg/$PKG_SUBDIR/build/"
+mount --mkdir --bind "$SRCDIR" "pkg/$ID/systemd-stable/"
+mount --mkdir --bind "$BUILDDIR" "pkg/$ID/build/"
 # Because we run with --noextract we are responsible for making sure the source files appear in src/.
-mount --mkdir --rbind "$PWD/pkg/$PKG_SUBDIR" "pkg/$PKG_SUBDIR/src/"
+mount --mkdir --rbind "$PWD/pkg/$ID" "pkg/$ID/src/"
 
 # shellcheck source=/dev/null
 . /etc/makepkg.conf
@@ -35,13 +38,13 @@ else
     TS="${SOURCE_DATE_EPOCH:-$(date +%s)}"
 fi
 
-sed --in-place "pkg/$PKG_SUBDIR/PKGBUILD" \
+sed --in-place "pkg/$ID/PKGBUILD" \
     --expression "s/^_tag=.*/_tag=$(cat meson.version)/" \
     --expression "s/^pkgrel=.*/pkgrel=$(date "+%Y%m%d%H%M%S" --date "@$TS")/"
 
 # We get around makepkg's root check by setting EUID to something else.
 # shellcheck disable=SC2046
-env --chdir="pkg/$PKG_SUBDIR" \
+env --chdir="pkg/$ID" \
     EUID=123 \
     makepkg \
     --noextract \
@@ -49,7 +52,7 @@ env --chdir="pkg/$PKG_SUBDIR" \
     --force \
     _systemd_UPSTREAM=1 \
     _systemd_QUIET=1 \
-    BUILDDIR="$PWD/pkg/$PKG_SUBDIR" \
+    BUILDDIR="$PWD/pkg/$ID" \
     PKGDEST="$OUTPUTDIR" \
     PKGEXT=".pkg.tar" \
     MESON_EXTRA_CONFIGURE_OPTIONS="-D mode=developer -D b_sanitize=${SANITIZERS:-none}"

mkosi.images/system/mkosi.conf.d/10-arch/mkosi.conf

@@ -10,7 +10,6 @@ InitrdInclude=initrd/
 # https://gitlab.archlinux.org/archlinux/packaging/packages/systemd/-/merge_requests/8 is merged.
 [Content]
 Environment=
-        PKG_SUBDIR="arch"
         SYSTEMD_PACKAGES="systemd systemd-ukify systemd-sysvcompat systemd-resolvconf systemd-tests"
 
 Packages=

mkosi.images/system/mkosi.conf.d/10-arch/mkosi.prepare

@@ -6,13 +6,16 @@ if [ "$1" = "build" ]; then
     exit 0
 fi
 
-if [ ! -f "pkg/$PKG_SUBDIR/PKGBUILD" ]; then
-    echo "PKGBUILD not found at pkg/$PKG_SUBDIR/PKGBUILD, run mkosi once with -ff to make sure the PKGBUILD is cloned" >&2
+# shellcheck source=/dev/null
+. "$BUILDROOT/usr/lib/os-release"
+
+if [ ! -f "pkg/$ID/PKGBUILD" ]; then
+    echo "PKGBUILD not found at pkg/$ID/PKGBUILD, run mkosi once with -ff to make sure the PKGBUILD is cloned" >&2
     exit 1
 fi
 
 # We get depends and optdepends from .SRCINFO as getting them from the PKGBUILD is rather complex.
-sed --expression 's/^[ \t]*//' "pkg/$PKG_SUBDIR/.SRCINFO" |
+sed --expression 's/^[ \t]*//' "pkg/$ID/.SRCINFO" |
     grep --regexp '^depends =' --regexp '^optdepends =' |
     sed --expression 's/^depends = //' --expression 's/^optdepends = //' --expression 's/:.*//' |
     xargs --delimiter '\n' mkosi-install
@@ -20,7 +23,7 @@ sed --expression 's/^[ \t]*//' "pkg/$PKG_SUBDIR/.SRCINFO" |
 # We get makedepends from the PKGBUILD as .SRCINFO can't encode conditional dependencies depending on
 # whether some environment variable is set or not.
 # shellcheck source=/dev/null
-_systemd_UPSTREAM=1 . "pkg/$PKG_SUBDIR/PKGBUILD"
+_systemd_UPSTREAM=1 . "pkg/$ID/PKGBUILD"
 
 # shellcheck disable=SC2154
 mkosi-install "${makedepends[@]}"

mkosi.images/system/mkosi.conf.d/10-centos-fedora/mkosi.build.chroot

@@ -2,8 +2,11 @@
 # SPDX-License-Identifier: LGPL-2.1-or-later
 set -e
 
-if [ ! -f "pkg/$PKG_SUBDIR/systemd.spec" ]; then
-    echo "spec not found at pkg/$PKG_SUBDIR/systemd.spec, run mkosi once with -ff to make sure the spec is cloned" >&2
+# shellcheck source=/dev/null
+. /usr/lib/os-release
+
+if [ ! -f "pkg/$ID/systemd.spec" ]; then
+    echo "spec not found at pkg/$ID/systemd.spec, run mkosi once with -ff to make sure the spec is cloned" >&2
     exit 1
 fi
 
@@ -23,7 +26,7 @@ rpmbuild \
     $( ((WITH_TESTS)) || echo "--nocheck") \
     $( ((WITH_DOCS))  || echo "--without docs") \
     --define "_topdir /var/tmp" \
-    --define "_sourcedir pkg/$PKG_SUBDIR" \
+    --define "_sourcedir pkg/$ID" \
     --define "_rpmdir $OUTPUTDIR" \
     ${BUILDDIR:+--define} \
     ${BUILDDIR:+"_vpath_builddir $BUILDDIR"} \
@@ -45,6 +48,6 @@ rpmbuild \
     --define "__elf_exclude_path ^/usr/lib/systemd/tests/unit-tests/.*$" \
     --define "__script_requires %{nil}" \
     --undefine _lto_cflags \
-    "pkg/$PKG_SUBDIR/systemd.spec"
+    "pkg/$ID/systemd.spec"
 
 cp "$OUTPUTDIR"/*.rpm "$PACKAGEDIR"

mkosi.images/system/mkosi.conf.d/10-centos-fedora/mkosi.prepare

@@ -6,8 +6,11 @@ if [ "$1" = "build" ]; then
     exit 0
 fi
 
-if [ ! -f "pkg/$PKG_SUBDIR/systemd.spec" ]; then
-    echo "spec not found at pkg/$PKG_SUBDIR/systemd.spec, run mkosi with -ff to make sure the spec is cloned" >&2
+# shellcheck source=/dev/null
+. "$BUILDROOT/usr/lib/os-release"
+
+if [ ! -f "pkg/$ID/systemd.spec" ]; then
+    echo "spec not found at pkg/$ID/systemd.spec, run mkosi with -ff to make sure the spec is cloned" >&2
     exit 1
 fi
 
@@ -18,8 +21,8 @@ for DEPS in --requires --buildrequires; do
         --query \
         "$DEPS" \
         --define "_topdir /var/tmp" \
-        --define "_sourcedir pkg/$PKG_SUBDIR" \
-        "pkg/$PKG_SUBDIR/systemd.spec" |
+        --define "_sourcedir pkg/$ID" \
+        "pkg/$ID/systemd.spec" |
             grep --invert-match --regexp systemd --regexp /bin/sh --regexp "rpmlib(" --regexp udev |
             sort --unique |
             tee /tmp/buildrequires |
@@ -29,7 +32,7 @@ done
 # rpmbuild -br tries to build a source package which means all source files have to exist which isn't the
 # case when using --build-in-place so we get rid of the source file that doesn't exist to make it happy.
 # TODO: Use -bd instead of -br and get rid of this once we don't need to build on CentOS Stream 9 anymore.
-sed '/Source0/d' --in-place "pkg/$PKG_SUBDIR/systemd.spec"
+sed '/Source0/d' --in-place "pkg/$ID/systemd.spec"
 
 until mkosi-chroot \
     rpmbuild \
@@ -37,9 +40,9 @@ until mkosi-chroot \
     --build-in-place \
     --with upstream \
     --define "_topdir /var/tmp" \
-    --define "_sourcedir pkg/$PKG_SUBDIR" \
+    --define "_sourcedir pkg/$ID" \
     --define "_build_name_fmt %%{NAME}-%%{VERSION}-%%{RELEASE}.%%{ARCH}.rpm" \
-    "pkg/$PKG_SUBDIR/systemd.spec"
+    "pkg/$ID/systemd.spec"
 do
     EXIT_STATUS=$?
     if [ $EXIT_STATUS -ne 11 ]; then

mkosi.images/system/mkosi.conf.d/10-centos/mkosi.conf

@@ -4,9 +4,6 @@
 Distribution=centos
 
 [Content]
-Environment=
-        PKG_SUBDIR="centos"
-
 Packages=
         kernel-modules # For squashfs support
         rpmautospec-rpm-macros

mkosi.images/system/mkosi.conf.d/10-debian-ubuntu/mkosi.build.chroot

@@ -2,13 +2,16 @@
 # SPDX-License-Identifier: LGPL-2.1-or-later
 set -e
 
-if [ ! -d "pkg/$PKG_SUBDIR/debian" ]; then
-    echo "deb rules not found at pkg/$PKG_SUBDIR/debian, run mkosi once with -ff to make sure the rules are cloned" >&2
+# shellcheck source=/dev/null
+. /usr/lib/os-release
+
+if [ ! -d "pkg/$ID/debian" ]; then
+    echo "deb rules not found at pkg/$ID/debian, run mkosi once with -ff to make sure the rules are cloned" >&2
     exit 1
 fi
 
 # We transplant the debian/ folder from the deb package sources into the upstream sources.
-mount --mkdir --bind "$SRCDIR/pkg/$PKG_SUBDIR/debian" "$SRCDIR"/debian
+mount --mkdir --bind "$SRCDIR/pkg/$ID/debian" "$SRCDIR"/debian
 
 # We hide the patches/ directory by mounting an empty directory on top so they don't get applied.
 TMP=$(mktemp -d)

mkosi.images/system/mkosi.conf.d/10-debian-ubuntu/mkosi.conf

@@ -9,7 +9,6 @@ InitrdInclude=initrd/
 
 [Content]
 Environment=
-        PKG_SUBDIR="debian"
         SYSTEMD_PACKAGES="systemd
                           systemd-userdbd
                           systemd-oomd

mkosi.images/system/mkosi.conf.d/10-debian-ubuntu/mkosi.prepare

@@ -6,10 +6,13 @@ if [ "$1" = "build" ]; then
     exit 0
 fi
 
-if [ ! -d "pkg/$PKG_SUBDIR/debian" ]; then
-    echo "deb rules not found at pkg/$PKG_SUBDIR/debian, run mkosi once with -ff to make sure the rules are cloned" >&2
+# shellcheck source=/dev/null
+. "$BUILDROOT/usr/lib/os-release"
+
+if [ ! -d "pkg/$ID/debian" ]; then
+    echo "deb rules not found at pkg/$ID/debian, run mkosi once with -ff to make sure the rules are cloned" >&2
     exit 1
 fi
 
-cd "pkg/$PKG_SUBDIR"
+cd "pkg/$ID"
 DEB_BUILD_PROFILES="pkg.systemd.upstream" apt-get build-dep .

mkosi.images/system/mkosi.conf.d/10-fedora/mkosi.conf

@@ -4,9 +4,6 @@
 Distribution=fedora
 
 [Content]
-Environment=
-        PKG_SUBDIR="fedora"
-
 Packages=
         btrfs-progs
         compsize

mkosi.images/system/mkosi.conf.d/10-opensuse/mkosi.build.chroot

@@ -2,8 +2,12 @@
 # SPDX-License-Identifier: LGPL-2.1-or-later
 set -e
 
-if [ ! -f "pkg/$PKG_SUBDIR/systemd.spec" ]; then
-    echo "spec not found at pkg/$PKG_SUBDIR/systemd.spec, run mkosi once with -ff to make sure the spec is cloned" >&2
+# shellcheck source=/dev/null
+. /usr/lib/os-release
+ID="${ID%-*}"
+
+if [ ! -f "pkg/$ID/systemd.spec" ]; then
+    echo "spec not found at pkg/$ID/systemd.spec, run mkosi once with -ff to make sure the spec is cloned" >&2
     exit 1
 fi
 
@@ -16,7 +20,7 @@ fi
 # The openSUSE filelists hardcode the manpage compression extension. This causes rpmbuild errors since we
 # disable manpage compression as the files cannot be found. Fix the issue by removing the compression
 # extension.
-find "pkg/$PKG_SUBDIR" -name "files.*" -exec sed --in-place 's/\.gz$//' {} \;
+find "pkg/$ID" -name "files.*" -exec sed --in-place 's/\.gz$//' {} \;
 
 build() {
     # TODO: Replace meson_build and meson_install overrides with "--undefine __meson_verbose" once
@@ -28,7 +32,7 @@ build() {
         --with upstream \
         $( ((WITH_TESTS)) || echo --nocheck) \
         --define "_topdir /var/tmp" \
-        --define "_sourcedir pkg/$PKG_SUBDIR" \
+        --define "_sourcedir pkg/$ID" \
         --define "_rpmdir $OUTPUTDIR" \
         ${BUILDDIR:+--define} \
         ${BUILDDIR:+"_vpath_builddir $BUILDDIR"} \
@@ -46,7 +50,7 @@ build() {
         --define "__elf_exclude_path ^/usr/lib/systemd/tests/unit-tests/.*$" \
         --define "__script_requires %{nil}" \
         "$@" \
-        "pkg/$PKG_SUBDIR/systemd.spec"
+        "pkg/$ID/systemd.spec"
 }
 
 if ! build; then
@@ -58,7 +62,7 @@ if ! build; then
     # warnings.
     rm systemd.lang
 
-    cat /tmp/unpackaged-files >>"pkg/$PKG_SUBDIR/files.systemd"
+    cat /tmp/unpackaged-files >>"pkg/$ID/files.systemd"
     build --noprep --nocheck
 fi
 

mkosi.images/system/mkosi.conf.d/10-opensuse/mkosi.conf

@@ -8,7 +8,6 @@ InitrdInclude=initrd/
 
 [Content]
 Environment=
-        PKG_SUBDIR="opensuse"
         SYSTEMD_PACKAGES="systemd
                           udev
                           systemd-experimental

mkosi.images/system/mkosi.conf.d/10-opensuse/mkosi.prepare

@@ -6,8 +6,12 @@ if [ "$1" = "build" ]; then
     exit 0
 fi
 
-if [ ! -f "pkg/$PKG_SUBDIR/systemd.spec" ]; then
-    echo "spec not found at pkg/$PKG_SUBDIR/systemd.spec, run mkosi once with -ff to make sure the spec is cloned" >&2
+# shellcheck source=/dev/null
+. "$BUILDROOT/usr/lib/os-release"
+ID="${ID%-*}"
+
+if [ ! -f "pkg/$ID/systemd.spec" ]; then
+    echo "spec not found at pkg/$ID/systemd.spec, run mkosi once with -ff to make sure the spec is cloned" >&2
     exit 1
 fi
 
@@ -18,8 +22,8 @@ for DEPS in --requires --buildrequires; do
         --query \
         "$DEPS" \
         --define "_topdir /var/tmp" \
-        --define "_sourcedir pkg/$PKG_SUBDIR" \
-        "pkg/$PKG_SUBDIR/systemd.spec" |
+        --define "_sourcedir pkg/$ID" \
+        "pkg/$ID/systemd.spec" |
             grep --invert-match --regexp systemd --regexp /bin/sh --regexp "rpmlib(" --regexp udev |
             sort --unique |
             tee /tmp/buildrequires |
@@ -32,9 +36,9 @@ until mkosi-chroot \
     --build-in-place \
     --with upstream \
     --define "_topdir /var/tmp" \
-    --define "_sourcedir pkg/$PKG_SUBDIR" \
+    --define "_sourcedir pkg/$ID" \
     --define "_build_name_fmt %%{NAME}-%%{VERSION}-%%{RELEASE}.%%{ARCH}.rpm" \
-    "pkg/$PKG_SUBDIR/systemd.spec"
+    "pkg/$ID/systemd.spec"
 do
     EXIT_STATUS=$?
     if [ $EXIT_STATUS -ne 11 ]; then

mkosi.images/system/mkosi.sync

@@ -2,7 +2,8 @@
 # SPDX-License-Identifier: LGPL-2.1-or-later
 set -e
 
-if [ -z "$(ls --almost-all "pkg/$PKG_SUBDIR")" ] || [ -f "pkg/$PKG_SUBDIR/.git" ]; then
-    git submodule sync "pkg/$PKG_SUBDIR"
-    git submodule update --init "pkg/$PKG_SUBDIR"
+if [ -z "$(ls --almost-all "pkg/$DISTRIBUTION")" ] || [ -f "pkg/$DISTRIBUTION/.git" ]; then
+    PKG_SUBDIR="$(realpath "pkg/$DISTRIBUTION" --relative-to "$PWD")"
+    git submodule sync "$PKG_SUBDIR"
+    git submodule update --init "$PKG_SUBDIR"
 fi

pkg/ubuntu

@@ -0,0 +1 @@
+debian