From 12519f01f936aa6223007cbbaba446ac204d3163 Mon Sep 17 00:00:00 2001
From: Tobias Pfandzelter <tp@mcc.tu-berlin.de>
Date: Tue, 26 Mar 2024 11:39:56 +0100
Subject: [PATCH] make rootfsbuilder nicer to use

---
 builder/Dockerfile      | 31 +++++++++++++++-----
 builder/build-script.sh | 65 +++++++++++++++++------------------------
 builder/prepare.sh      | 13 ---------
 3 files changed, 50 insertions(+), 59 deletions(-)

diff --git a/builder/Dockerfile b/builder/Dockerfile
index 15eca66..d96d0e1 100644
--- a/builder/Dockerfile
+++ b/builder/Dockerfile
@@ -36,17 +36,34 @@ RUN wget http://dl-cdn.alpinelinux.org/alpine/v${ALPINE_VERSION_MAJOR}.${ALPINE_
     cd minirootfs && \
     tar xzf ../alpine-minirootfs-${ALPINE_VERSION}-${ALPINE_ARCH}.tar.gz && \
     cd .. && \
-    rm alpine-minirootfs-${ALPINE_VERSION}-${ALPINE_ARCH}.tar.gz
+    rm alpine-minirootfs-${ALPINE_VERSION}-${ALPINE_ARCH}.tar.gz && \
+    mkdir -p ./rootfs && \
+    cp -r  minirootfs/* ./rootfs/ && \
+    rm -rf minirootfs
+
+# install dependencies in minirootfs
+RUN cp /etc/resolv.conf ./rootfs/etc/resolv.conf && \
+    chroot ./rootfs/ apk -X "http://dl-5.alpinelinux.org/alpine/latest-stable/main" -U --allow-untrusted --root / --initdb add \
+    openrc \
+    ca-certificates \
+    alpine-base \
+    util-linux \
+    iptables \
+    iproute2 \
+    strace \
+    attr \
+    grep \
+    chrony
 
 COPY fcinit.c fcinit.c
-RUN gcc -static -O3 -o ./fcinit fcinit.c && \
+RUN gcc -static -O3 -o ./rootfs/sbin/fcinit fcinit.c && \
     rm fcinit.c
 
-COPY inittab inittab
-COPY interfaces interfaces
-COPY run-user-script run-user-script
-COPY prepare.sh prepare.sh
-COPY ceinit ceinit
+COPY inittab ./rootfs/etc/inittab
+COPY interfaces ./rootfs/etc/network/interfaces
+COPY run-user-script ./rootfs/sbin/run-user-script
+COPY prepare.sh ./rootfs/prepare.sh
+COPY ceinit ./rootfs/sbin/ceinit
 
 COPY build-script.sh /build-script.sh
 
diff --git a/builder/build-script.sh b/builder/build-script.sh
index 7a6b593..dca79db 100644
--- a/builder/build-script.sh
+++ b/builder/build-script.sh
@@ -21,59 +21,46 @@
 
 set -ex
 
-mkdir -p ./tmp
-
-cp -r  minirootfs/* ./tmp/
-
-# if you don't do this, apk can't access its repositories
-cp /etc/resolv.conf ./tmp/etc/resolv.conf
 # mount /dev/random and /dev/urandom (needed for some operations, such as git)
-mkdir -p ./tmp/dev
-touch ./tmp/dev/random
-mount --rbind /dev/random ./tmp/dev/random
-mount --make-rslave ./tmp/dev/random
-touch ./tmp/dev/urandom
-mount --rbind /dev/urandom ./tmp/dev/urandom
-mount --make-rslave ./tmp/dev/urandom
+mkdir -p ./rootfs/dev
+touch ./rootfs/dev/random
+mount --rbind /dev/random ./rootfs/dev/random
+mount --make-rslave ./rootfs/dev/random
+touch ./rootfs/dev/urandom
+mount --rbind /dev/urandom ./rootfs/dev/urandom
+mount --make-rslave ./rootfs/dev/urandom
 
-# copy the necessary files
-cp interfaces ./tmp/etc/network/interfaces
-cp inittab ./tmp/etc/inittab
-cp run-user-script ./tmp/sbin/run-user-script
-cp fcinit ./tmp/sbin/fcinit
-cp ceinit ./tmp/sbin/ceinit
-cp /app.sh ./tmp/app.sh
+# # copy the necessary files
+cp /app.sh ./rootfs/app.sh
 
 if [ -d "/files" ]; then
-    cp -rv /files/* ./tmp/
+    cp -rv /files/* ./rootfs/
 fi
 
-cp prepare.sh ./tmp/prepare.sh
-chroot ./tmp/ /bin/sh /prepare.sh
+chroot ./rootfs/ /bin/sh /prepare.sh
+rm ./rootfs/prepare.sh
 
 if [ -f "/base.sh" ]; then
-    cp /base.sh ./tmp/base.sh
-    chroot ./tmp/ /bin/sh base.sh
-    rm ./tmp/base.sh
+    cp /base.sh ./rootfs/base.sh
+    chroot ./rootfs/ /bin/sh base.sh
+    rm ./rootfs/base.sh
 fi
 
 # these are the mount points we need to create
-mkdir -p ./tmp/overlay/root \
-    ./tmp/overlay/work \
-    ./tmp/mnt \
-    ./tmp/rom
+mkdir -p ./rootfs/overlay/root \
+    ./rootfs/overlay/work \
+    ./rootfs/mnt \
+    ./rootfs/rom
 
 # now delete the nameserver config again
-rm ./tmp/etc/resolv.conf
-ln -s /proc/net/pnp ./tmp/etc/resolv.conf
+rm ./rootfs/etc/resolv.conf
+ln -s /proc/net/pnp ./rootfs/etc/resolv.conf
 # and unmount the devices
-umount ./tmp/dev/random
-rm ./tmp/dev/random
-umount ./tmp/dev/urandom
-rm ./tmp/dev/urandom
-
-rm ./tmp/prepare.sh
+umount ./rootfs/dev/random
+rm ./rootfs/dev/random
+umount ./rootfs/dev/urandom
+rm ./rootfs/dev/urandom
 
-mksquashfs ./tmp rootfs.img -noappend
+mksquashfs ./rootfs rootfs.img -noappend
 
 mv rootfs.img /opt/code/"$1"
diff --git a/builder/prepare.sh b/builder/prepare.sh
index d765796..1475529 100755
--- a/builder/prepare.sh
+++ b/builder/prepare.sh
@@ -16,19 +16,6 @@
 # along with this program. If not, see <http://www.gnu.org/licenses/>.
 #
 
-# install dependencies
-apk -X "http://dl-5.alpinelinux.org/alpine/latest-stable/main" -U --allow-untrusted --root / --initdb add \
-    openrc \
-    ca-certificates \
-    alpine-base \
-    util-linux \
-    iptables \
-    iproute2 \
-    strace \
-    attr \
-    grep \
-    chrony
-
 # link rc services
 ln -sf /etc/init.d/devfs        /etc/runlevels/boot/devfs
 ln -sf /etc/init.d/procfs       /etc/runlevels/boot/procfs