Find boot image with MagiskInstaller

Fix #8211

scripts/app_functions.sh

@@ -2,10 +2,14 @@
 # Magisk app internal scripts
 ##################################
 
+# $1 = delay
+# $2 = command
 run_delay() {
   (sleep $1; $2)&
 }
 
+# $1 = version string
+# $2 = version code
 env_check() {
   for file in busybox magiskboot magiskinit util_functions.sh boot_patch.sh; do
     [ -f "$MAGISKBIN/$file" ] || return 1
@@ -21,6 +25,8 @@ env_check() {
   return 0
 }
 
+# $1 = dir to copy
+# $2 = destination (optional)
 cp_readlink() {
   if [ -z $2 ]; then
     cd $1
@@ -39,6 +45,7 @@ cp_readlink() {
   cd /
 }
 
+# $1 = install dir
 fix_env() {
   # Cleanup and make dirs
   rm -rf $MAGISKBIN/*
@@ -49,6 +56,8 @@ fix_env() {
   chown -R 0:0 $MAGISKBIN
 }
 
+# $1 = install dir
+# $2 = boot partition
 direct_install() {
   echo "- Flashing new boot image"
   flash_image $1/new-boot.img $2
@@ -70,6 +79,7 @@ direct_install() {
   return 0
 }
 
+# $1 = uninstaller zip
 run_uninstaller() {
   rm -rf /dev/tmp
   mkdir -p /dev/tmp/install
@@ -77,24 +87,16 @@ run_uninstaller() {
   INSTALLER=/dev/tmp/install sh /dev/tmp/install/assets/uninstaller.sh dummy 1 "$1"
 }
 
+# $1 = boot partition
 restore_imgs() {
   local SHA1=$(grep_prop SHA1 $MAGISKTMP/.magisk/config)
   local BACKUPDIR=/data/magisk_backup_$SHA1
   [ -d $BACKUPDIR ] || return 1
-
-  get_flags
-  find_boot_image
-
-  for name in dtb dtbo; do
-    [ -f $BACKUPDIR/${name}.img.gz ] || continue
-    local IMAGE=$(find_block $name$SLOT)
-    [ -z $IMAGE ] && continue
-    flash_image $BACKUPDIR/${name}.img.gz $IMAGE
-  done
   [ -f $BACKUPDIR/boot.img.gz ] || return 1
-  flash_image $BACKUPDIR/boot.img.gz $BOOTIMAGE
+  flash_image $BACKUPDIR/boot.img.gz $1
 }
 
+# $1 = path to bootctl executable
 post_ota() {
   cd /data/adb
   cp -f $1 bootctl
@@ -131,6 +133,8 @@ EOF
   cd /
 }
 
+# $1 = APK
+# $2 = package name
 adb_pm_install() {
   local tmp=/data/local/tmp/temp.apk
   cp -f "$1" $tmp