From 429710af8f098d5545d6b08b352a06b058308f2d Mon Sep 17 00:00:00 2001
From: Christopher Roy Bratusek <nano@jpberlin.de>
Date: Fri, 9 Mar 2018 20:10:38 +0100
Subject: [PATCH] patcher: initial A/B partition scheme support

---
 ChangeLog.md                                  |  4 ++
 .../META-INF/com/google/android/update-binary | 40 ++++++++++++++-----
 patcher/dexpatcher/75-nanodroidpatcher.sh     | 39 +++++++++++++-----
 3 files changed, 63 insertions(+), 20 deletions(-)

diff --git a/ChangeLog.md b/ChangeLog.md
index 910c1e1..05d56b4 100644
--- a/ChangeLog.md
+++ b/ChangeLog.md
@@ -2,6 +2,10 @@
 
 ## 16.3 in-dev
 
+* Full, microG, F-Droid packages
+  * improved A/B partition scheme support
+* Patcher
+  * initial A/B parition scheme support
 * Updates (automatic)
   * AnySoftKeyboard (1.9.1117)
   * Déjà Vu nlpBackend (1.1.3)
diff --git a/patcher/META-INF/com/google/android/update-binary b/patcher/META-INF/com/google/android/update-binary
index 33ed8fd..4eb29d4 100644
--- a/patcher/META-INF/com/google/android/update-binary
+++ b/patcher/META-INF/com/google/android/update-binary
@@ -81,6 +81,34 @@ mount_image() {
 	fi
 }
 
+# taken from Magisk, with minor modifications for NanoDroid
+mount_partitions () {
+	SLOT=$(getprop ro.boot.slot_suffix)
+	if [ -z ${SLOT} ]; then
+		SLOT=$(getprop ro.boot.slot)
+		[ "${SLOT}" = "_" ] && SLOT=
+	fi
+
+	is_mounted /data || mount /data 2>/dev/null
+
+	${BOOTMODE} || mount -o bind /dev/urandom /dev/random
+
+	[ ! -f /system/build.prop ] && mount -o ro /system 2>/dev/null
+
+	if [ ! -f /system/build.prop ]; then
+		SYSTEMBLOCK=$(find /dev/block -iname system${SLOT} | head -n 1)
+		mount -t ext4 -o ro $SYSTEMBLOCK /system
+	fi
+
+	if [ -f /system/init.rc ]; then
+		mkdir /system_root 2>/dev/null
+		mount --move /system /system_root
+		mount -o bind /system_root/system /system
+	fi
+
+	[ ! -f /system/build.prop ] && error "failed to mount /system"
+}
+
 error () {
 	ui_print "${@}"
 	magisk_cleanup
@@ -454,11 +482,7 @@ nanodroid_sigspoofui=0
 get_config .nanodroid-setup
 [ "$config_exists" -eq 1 ] && source ${config}
 
-if ! (is_mounted /data); then
-	mount -orw /data || error " !! failed to mount /data"
-else	mount -orw,remount /data || \
-		error " !! failed to remount /data read-write"
-fi
+mount_partition
 
 if [ -f /data/adb/.nanodroid-patcher ]; then
 	ui_print " !! /data/adb/.nanodroid-patcher exists"
@@ -466,12 +490,6 @@ if [ -f /data/adb/.nanodroid-patcher ]; then
 	error    " !! remove this file and try again"
 fi
 
-if ! (is_mounted /system); then
-	mount -orw /system || error " !! failed to mount /system"
-else	mount -orw,remount /system || \
-		error " !! failed to remount /system read-write"
-fi
-
 setup_patcher
 
 detect_sdk
diff --git a/patcher/dexpatcher/75-nanodroidpatcher.sh b/patcher/dexpatcher/75-nanodroidpatcher.sh
index d761271..374e6fc 100644
--- a/patcher/dexpatcher/75-nanodroidpatcher.sh
+++ b/patcher/dexpatcher/75-nanodroidpatcher.sh
@@ -68,6 +68,34 @@ mount_image() {
 	fi
 }
 
+# taken from Magisk, with minor modifications for NanoDroid
+mount_partitions () {
+	SLOT=$(getprop ro.boot.slot_suffix)
+	if [ -z ${SLOT} ]; then
+		SLOT=$(getprop ro.boot.slot)
+		[ "${SLOT}" = "_" ] && SLOT=
+	fi
+
+	is_mounted /data || mount /data 2>/dev/null
+
+	${BOOTMODE} || mount -o bind /dev/urandom /dev/random
+
+	[ ! -f /system/build.prop ] && mount -o ro /system 2>/dev/null
+
+	if [ ! -f /system/build.prop ]; then
+		SYSTEMBLOCK=$(find /dev/block -iname system${SLOT} | head -n 1)
+		mount -t ext4 -o ro $SYSTEMBLOCK /system
+	fi
+
+	if [ -f /system/init.rc ]; then
+		mkdir /system_root 2>/dev/null
+		mount --move /system /system_root
+		mount -o bind /system_root/system /system
+	fi
+
+	[ ! -f /system/build.prop ] && error "failed to mount /system"
+}
+
 error () {
 	ui_print "${@}"
 	magisk_cleanup
@@ -389,18 +417,11 @@ main () {
 	ui_print "*******************************"
 	ui_print " "
 
+	mount_partitions
+
 	[ -f /data/adb/.nanodroid-patcher ] && \
 		rm -f /data/adb/.nanodroid-patcher
 
-	if ! (is_mounted /data); then
-		mount -orw /data || error " !! failed to mount /data"
-	else	mount -orw,remount /data || error " !! failed to remount /data read-write"
-	fi
-
-	if ! (is_mounted /system); then
-		mount -oro /system || error " !! failed to mount /system"
-	fi
-
 	get_config .nanodroid-setup
 	[ "$config_exists" -eq 1 ] && source ${config}