feat: use init and entrypoint from device tree

skel/sbin/init

@@ -1,6 +1,6 @@
 #!/bin/busybox sh
 
-# Copyright 2019 Cartesi Pte. Ltd.
+# Copyright 2023 Cartesi Pte. Ltd.
 #
 # Licensed under the Apache License, Version 2.0 (the "License"); you may not
 # use this file except in compliance with the License. You may obtain a copy of
@@ -13,11 +13,6 @@
 # the License.
 #
 
-# rndaddentropy can be in different places, make sure we can find it
-export PATH=/opt/cartesi/bin:"$PATH"
-
-[ ! -f /opt/cartesi/etc/motd -o "$splash" == "no" ] || busybox cat /opt/cartesi/etc/motd
-
 # mount
 busybox mkdir -p /dev/pts /dev/shm
 busybox mount -t proc proc /proc -o nosuid,nodev,noexec
@@ -26,31 +21,27 @@ busybox mount -t devpts devpts /dev/pts -o nosuid,noexec,gid=5,mode=620
 busybox mount -t tmpfs tmpfs /dev/shm -o nosuid,nodev,mode=1777
 #busybox mdev -s
 
-# rand
-if [ -f /opt/cartesi/var/run/random-seed ]; then
-    rndaddentropy < /opt/cartesi/var/run/random-seed
-    busybox chmod 600 /opt/cartesi/var/run/random-seed
-fi
-
-# disk
-if [ -d /mnt ]; then
-    (cd /sys/block && for DEV in *; do
-        [ ! "$DEV" = "mtdblock0" ] && \
-        NAME=$(busybox cat /sys/block/"$DEV"/device/name) && \
-        busybox mkdir "/mnt/$NAME" && \
-        busybox mount "/dev/$DEV" "/mnt/$NAME"
-    done)
-fi
-
 # net
 [ -f /etc/hostname ] && busybox hostname -F /etc/hostname
 busybox ifconfig lo 127.0.0.1
 
-# cmdline application
-if [ -n "$*" ]; then
-    [ -f /etc/environment ] && \
-        source /etc/environment && \
-        export PATH=/opt/cartesi/bin:"$PATH" # put it back on PATH
+# custom init
+if [ -f /proc/device-tree/cartesi/init ]; then
+    . /proc/device-tree/cartesi/init
+fi
+
+# use entrypoint from device tree if not empty, otherwise fallback to cmdline from bootargs
+if [ -s /proc/device-tree/cartesi/entrypoint ]; then
+    ENTRYPOINT=". /proc/device-tree/cartesi/entrypoint"
+else
+    ENTRYPOINT="$*"
+fi
+
+# application entrypoint
+if [ -n "$ENTRYPOINT" ]; then
+    [ -f /etc/environment ] && . /etc/environment
+    # put cartesi tools on PATH
+    export PATH=/opt/cartesi/bin:"$PATH"
 
     # can login as dapp user?
     if [ ! "$single" == "yes" ] && busybox id dapp &> /dev/null; then
@@ -67,11 +58,11 @@ if [ -n "$*" ]; then
         export HOME=~root USER=root LOGNAME=root
     fi
 
-    # execute cmdline
+    # execute entrypoint
     cd $HOME &&
         busybox setsid \
         busybox cttyhack \
-        busybox su -p $USER -c "$*"
+        busybox su -p $USER -c "$ENTRYPOINT"
 else
     echo "Nothing to do."
 fi