Never allow multiple root implementation

module/src/customize.sh

@@ -28,6 +28,12 @@ if [ "$BOOTMODE" ] && [ "$KSU" ]; then
     ui_print "! Please update KernelSU Manager to latest version"
     abort    "*********************************************************"
   fi
+  if [ "$(which magisk)" ]; then
+    ui_print "*********************************************************"
+    ui_print "! Multiple root implementation is NOT supported!"
+    ui_print "! Please uninstall Magisk before installing Zygisksu"
+    abort    "*********************************************************"
+  fi
 elif [ "$BOOTMODE" ] && [ "$MAGISK_VER_CODE" ]; then
   ui_print "- Installing from Magisk app"
   if [ "$MAGISK_VER_CODE" -lt "$MIN_MAGISK_VERSION" ]; then

module/src/post-fs-data.sh

@@ -8,7 +8,7 @@ fi
 cd "$MODDIR"
 export NATIVE_BRIDGE=$(getprop ro.dalvik.vm.native.bridge)
 
-if [ $(which magisk) ] && [ ".." -ef "/data/adb/modules" ]; then
+if [ "$(which magisk)" ] && [ ".." -ef "/data/adb/modules" ]; then
   for file in ../*; do
     if [ -d "$file" ] && [ -d "$file/zygisk" ] && ! [ -f "$file/disable" ]; then
       if [ -f "$file/post-fs-data.sh" ]; then

module/src/service.sh

@@ -7,7 +7,7 @@ fi
 
 cd "$MODDIR"
 
-if [ $(which magisk) ] && [ ".." -ef "/data/adb/modules" ]; then
+if [ "$(which magisk)" ] && [ ".." -ef "/data/adb/modules" ]; then
   for file in ../*; do
     if [ -d "$file" ] && [ -d "$file/zygisk" ] && ! [ -f "$file/disable" ]; then
       if [ -f "$file/service.sh" ]; then

zygiskd/src/root_impl/magisk.rs

@@ -4,12 +4,12 @@ use crate::constants::MIN_MAGISK_VERSION;
 
 pub fn is_magisk() -> Result<bool> {
     let version: Option<i32> = Command::new("magisk")
-        .arg("--version")
+        .arg("-V")
         .stdout(Stdio::piped())
         .spawn().ok()
         .and_then(|child| child.wait_with_output().ok())
         .and_then(|output| String::from_utf8(output.stdout).ok())
-        .and_then(|output| output.parse().ok());
+        .and_then(|output| output.trim().parse().ok());
     if let Some(version) = version {
         if version < MIN_MAGISK_VERSION {
             bail!("Magisk version too old: {}", version);

zygiskd/src/root_impl/mod.rs

@@ -13,6 +13,9 @@ static ROOT_IMPL: OnceCell<RootImpl> = OnceCell::new();
 
 pub fn setup() -> Result<()> {
     if kernelsu::is_kernel_su()? {
+        if let Ok(true) = magisk::is_magisk() {
+            bail!("Multiple root implementation");
+        }
         let _ = ROOT_IMPL.set(RootImpl::KernelSU);
     } else if magisk::is_magisk()? {
         let _ = ROOT_IMPL.set(RootImpl::Magisk);