Disable editing repeater credentials on Android 5

mobile/src/main/java/be/mygod/vpnhotspot/manage/RepeaterManager.kt

@@ -1,21 +1,21 @@
 package be.mygod.vpnhotspot.manage
 
+import android.annotation.TargetApi
 import android.content.ComponentName
 import android.content.DialogInterface
 import android.content.Intent
 import android.content.ServiceConnection
-import androidx.databinding.BaseObservable
-import androidx.databinding.Bindable
 import android.net.wifi.WifiConfiguration
 import android.net.wifi.p2p.WifiP2pGroup
 import android.os.IBinder
-import androidx.core.content.ContextCompat
-import androidx.appcompat.app.AlertDialog
-import androidx.appcompat.app.AppCompatDialog
-import androidx.recyclerview.widget.RecyclerView
 import android.view.WindowManager
 import android.widget.EditText
-import android.widget.Toast
+import androidx.appcompat.app.AlertDialog
+import androidx.appcompat.app.AppCompatDialog
+import androidx.core.content.ContextCompat
+import androidx.databinding.BaseObservable
+import androidx.databinding.Bindable
+import androidx.recyclerview.widget.RecyclerView
 import be.mygod.vpnhotspot.*
 import be.mygod.vpnhotspot.App.Companion.app
 import be.mygod.vpnhotspot.databinding.ListitemRepeaterBinding
@@ -114,7 +114,7 @@ class RepeaterManager(private val parent: TetheringFragment) : Manager(), Servic
                     var dialog: WifiP2pDialog? = null
                     dialog = WifiP2pDialog(mainActivity, DialogInterface.OnClickListener { _, which ->
                         when (which) {
-                            DialogInterface.BUTTON_POSITIVE -> when (conf.update(dialog!!.config!!)) {
+                            DialogInterface.BUTTON_POSITIVE -> @TargetApi(23) when (conf.update(dialog!!.config!!)) {
                                 true -> app.handler.postDelayed(binder::requestGroupUpdate, 1000)
                                 false -> mainActivity.snackbar().setText(R.string.noisy_su_failure).show()
                                 null -> mainActivity.snackbar().setText(R.string.root_unavailable).show()

mobile/src/main/java/be/mygod/vpnhotspot/net/wifi/P2pSupplicantConfiguration.kt

@@ -3,6 +3,7 @@ package be.mygod.vpnhotspot.net.wifi
 import android.net.wifi.WifiConfiguration
 import android.os.Build
 import android.util.Log
+import androidx.annotation.RequiresApi
 import be.mygod.vpnhotspot.App.Companion.app
 import be.mygod.vpnhotspot.util.loggerSu
 import be.mygod.vpnhotspot.util.noisySu
@@ -47,6 +48,8 @@ class P2pSupplicantConfiguration {
         }
     }
 
+    // pkill not available on Lollipop. Source: https://android.googlesource.com/platform/system/core/+/master/shell_and_utilities/README.md
+    @RequiresApi(23)
     fun update(config: WifiConfiguration): Boolean? {
         val content = content ?: return null
         val tempFile = File.createTempFile("vpnhotspot-", ".conf", app.cacheDir)
@@ -71,10 +74,7 @@ class P2pSupplicantConfiguration {
                 Crashlytics.log(Log.WARN, TAG, "Invalid conf ($ssidFound, $pskFound): $content")
             }
             if (ssidFound == 0 || pskFound == 0) return false
-            // pkill not available on Lollipop. Source: https://android.googlesource.com/platform/system/core/+/master/shell_and_utilities/README.md
+            return noisySu("cat ${tempFile.absolutePath} > /data/misc/wifi/p2p_supplicant.conf", "pkill wpa_supplicant")
-            return noisySu("cat ${tempFile.absolutePath} > /data/misc/wifi/p2p_supplicant.conf",
-                    if (Build.VERSION.SDK_INT >= 23) "pkill wpa_supplicant"
-                    else "set `ps | grep wpa_supplicant`; kill \$2")
         } finally {
             if (!tempFile.delete()) tempFile.deleteOnExit()
         }

mobile/src/main/java/be/mygod/vpnhotspot/net/wifi/WifiP2pDialog.kt

@@ -4,6 +4,7 @@ import android.content.Context
 import android.content.DialogInterface
 import android.net.wifi.WifiConfiguration
 import android.net.wifi.WifiConfiguration.AuthAlgorithm
+import android.os.Build
 import android.os.Bundle
 import com.google.android.material.textfield.TextInputLayout
 import androidx.appcompat.app.AlertDialog
@@ -46,7 +47,10 @@ class WifiP2pDialog(mContext: Context, private val mListener: DialogInterface.On
         setTitle(R.string.repeater_configure)
         mSsid = mView.findViewById(R.id.ssid)
         mPassword = mView.findViewById(R.id.password)
-        setButton(BUTTON_SUBMIT, context.getString(R.string.wifi_save), mListener)
+        // Note: Reading persistent group information in p2p_supplicant.conf wasn't available until this commit:
+        // https://android.googlesource.com/platform/external/wpa_supplicant_8/+/216983bceec7c450951e2fbcd076b5c75d432e57%5E%21/
+        // which isn't merged until Android 6.0.
+        if (Build.VERSION.SDK_INT >= 23) setButton(BUTTON_SUBMIT, context.getString(R.string.wifi_save), mListener)
         setButton(DialogInterface.BUTTON_NEGATIVE,
                 context.getString(R.string.wifi_cancel), mListener)
         setButton(DialogInterface.BUTTON_NEUTRAL, context.getString(R.string.repeater_reset_credentials), mListener)