mkosi: Move copying packages to the output directory to the postinst script

Now that we have the mkosi.clangd script to run clangd from the mkosi
build script, it becomes clear that doing cleanup with mkosi.clean has
a big gap in that we always run the mkosi.clean script and thus we also
run it when we run the mkosi.clangd script, causing the previously built
packages to be removed when we run clangd without producing new ones.

In mkosi we're improving the situation by only running clean scripts when we
clean up the output directory and disallowing writing to the output directory
from build scripts.

Let's adapt systemd to these changes by moving the copying of packages to the
output directory to the postinst script.

mkosi.functions

@@ -52,6 +52,4 @@ EOF
         --copy-source="$1" \
         --pretty=no \
         "$BUILDDIR"/systemd.raw
-
-    cp "$BUILDDIR"/systemd.raw "$OUTPUTDIR"
 }

mkosi.images/build/mkosi.conf.d/arch/mkosi.build.chroot

@@ -68,6 +68,11 @@ sed --in-place "pkg/$PKG_SUBDIR/PKGBUILD" \
     --expression "s/^_tag=.*/_tag=$(cat meson.version)/" \
     --expression "s/^pkgrel=.*/pkgrel=$(date "+%Y%m%d%H%M%S" --date "@$TS")/"
 
+(
+    shopt -s nullglob
+    rm -f "$BUILDDIR"/*.pkg.tar
+)
+
 # We get around makepkg's root check by setting EUID to something else.
 # Linting the PKGBUILD takes multiple seconds every build so avoid that by nuking all the linting functions.
 # shellcheck disable=SC2046
@@ -82,14 +87,8 @@ env --chdir="pkg/$PKG_SUBDIR" \
     _systemd_UPSTREAM=1 \
     _systemd_QUIET=$( ((MESON_VERBOSE)); echo $? ) \
     BUILDDIR="$PWD/pkg/$PKG_SUBDIR" \
-    PKGDEST="$OUTPUTDIR" \
+    PKGDEST="$BUILDDIR" \
     PKGEXT=".pkg.tar" \
     MESON_EXTRA_CONFIGURE_OPTIONS="$MKOSI_MESON_OPTIONS $MESON_OPTIONS"
 
-(
-    shopt -s nullglob
-    rm -f "$BUILDDIR"/*.pkg.tar
-)
-
-cp "$OUTPUTDIR"/*.pkg.tar "$PACKAGEDIR"
-cp "$OUTPUTDIR"/*.pkg.tar "$BUILDDIR"
+cp "$BUILDDIR"/*.pkg.tar "$PACKAGEDIR"

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

@@ -53,6 +53,11 @@ if ((WIPE)) && [[ -d "$BUILDDIR/meson-private" ]]; then
     MKOSI_MESON_OPTIONS="$MKOSI_MESON_OPTIONS --wipe"
 fi
 
+(
+    shopt -s nullglob
+    rm -f "$BUILDDIR"/*.rpm
+)
+
 IFS=
 # TODO: Replace meson_build and meson_install overrides with "--undefine __meson_verbose" once
 # https://github.com/mesonbuild/meson/pull/12835 is available.
@@ -73,7 +78,7 @@ CXX_LD="$( ((LLVM)) && echo lld)" \
     $( ((WITH_DOCS))  || echo "--without=docs") \
     --define "_topdir /var/tmp" \
     --define "_sourcedir $PWD/pkg/$PKG_SUBDIR" \
-    --define "_rpmdir $OUTPUTDIR" \
+    --define "_rpmdir $BUILDDIR" \
     ${BUILDDIR:+"--define=_vpath_builddir $BUILDDIR"} \
     --define "_build_name_fmt %%{NAME}-%%{VERSION}-%%{RELEASE}.%%{ARCH}.rpm" \
     --define "_binary_payload w.ufdio" \
@@ -101,12 +106,6 @@ CXX_LD="$( ((LLVM)) && echo lld)" \
     --noclean \
     "pkg/$PKG_SUBDIR/systemd.spec"
 
-(
-    shopt -s nullglob
-    rm -f "$BUILDDIR"/*.rpm
-)
-
-cp "$OUTPUTDIR"/*.rpm "$PACKAGEDIR"
-cp "$OUTPUTDIR"/*.rpm "$BUILDDIR"
+cp "$BUILDDIR"/*.rpm "$PACKAGEDIR"
 
 make_sysext_unsigned /var/tmp/BUILD/*/BUILDROOT

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

@@ -133,8 +133,8 @@ fi
     rm -f "$BUILDDIR"/*.deb "$BUILDDIR"/*.ddeb
 
     cp ../*.deb ../*.ddeb "$PACKAGEDIR"
-    cp ../*.deb ../*.ddeb "$OUTPUTDIR"
     cp ../*.deb ../*.ddeb "$BUILDDIR"
+
     # These conflict with the packages that we actually want to install, so remove them
     rm -f "$BUILDDIR"/systemd-standalone-*.deb "$BUILDDIR"/systemd-standalone-*.ddeb
 )

mkosi.images/build/mkosi.conf.d/opensuse/mkosi.build.chroot

@@ -75,7 +75,7 @@ build() {
         $( ((WITH_TESTS)) || echo "--nocheck") \
         --define "_topdir /var/tmp" \
         --define "_sourcedir $PWD/pkg/$PKG_SUBDIR" \
-        --define "_rpmdir $OUTPUTDIR" \
+        --define "_rpmdir $BUILDDIR" \
         ${BUILDDIR:+"--define=_vpath_builddir $BUILDDIR"} \
         --define "_build_name_fmt %%{NAME}-%%{VERSION}-%%{RELEASE}.%%{ARCH}.rpm" \
         --define "_binary_payload w.ufdio" \
@@ -106,6 +106,11 @@ build() {
     return $EXIT_STATUS
 }
 
+(
+    shopt -s nullglob
+    rm -f "$BUILDDIR"/*.rpm
+)
+
 if ! build; then
     if [[ ! -s /tmp/unpackaged-files ]]; then
         exit 1
@@ -119,12 +124,6 @@ if ! build; then
     build --noprep --nocheck
 fi
 
-(
-    shopt -s nullglob
-    rm -f "$BUILDDIR"/*.rpm
-)
-
-cp "$OUTPUTDIR"/*.rpm "$PACKAGEDIR"
-cp "$OUTPUTDIR"/*.rpm "$BUILDDIR"
+cp "$BUILDDIR"/*.rpm "$PACKAGEDIR"
 
 make_sysext_unsigned /var/tmp/BUILD/*/BUILDROOT

mkosi.postinst.chroot

@@ -3,6 +3,8 @@
 set -e
 set -o nounset
 
+find "$BUILDDIR" \( -name "*.rpm" -o -name "*.deb" -o -name "*.pkg.tar" -o -name systemd.raw \) -exec cp -t "$OUTPUTDIR" {} \;
+
 useradd \
     --uid 4711 \
     --user-group \