Fix SecurityExceptions caused by LOH

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

@@ -2,13 +2,16 @@ package be.mygod.vpnhotspot.manage
 
 import android.Manifest
 import android.annotation.TargetApi
+import android.content.ActivityNotFoundException
 import android.content.ComponentName
 import android.content.Intent
 import android.content.ServiceConnection
 import android.content.pm.PackageManager
 import android.os.IBinder
+import android.provider.Settings
 import android.support.v7.widget.RecyclerView
 import android.view.View
+import android.widget.Toast
 import be.mygod.vpnhotspot.LocalOnlyHotspotService
 import be.mygod.vpnhotspot.R
 import be.mygod.vpnhotspot.databinding.ListitemInterfaceBinding
@@ -31,13 +34,28 @@ class LocalOnlyHotspotManager(private val parent: TetheringFragment) : Manager()
             val binder = manager.binder
             if (binder?.iface != null) binder.stop() else {
                 val context = manager.parent.requireContext()
-                if (context.checkSelfPermission(Manifest.permission.ACCESS_COARSE_LOCATION) ==
+                if (context.checkSelfPermission(Manifest.permission.ACCESS_COARSE_LOCATION) !=
                         PackageManager.PERMISSION_GRANTED) {
-                    context.startForegroundService(Intent(context, LocalOnlyHotspotService::class.java))
-                } else {
                     manager.parent.requestPermissions(arrayOf(Manifest.permission.ACCESS_COARSE_LOCATION),
                             TetheringFragment.START_LOCAL_ONLY_HOTSPOT)
+                    return
                 }
+                /**
+                 * LOH also requires location to be turned on. Source:
+                 * https://android.googlesource.com/platform/frameworks/opt/net/wifi/+/53e0284/service/java/com/android/server/wifi/WifiServiceImpl.java#1204
+                 * https://android.googlesource.com/platform/frameworks/opt/net/wifi/+/53e0284/service/java/com/android/server/wifi/WifiSettingsStore.java#228
+                 */
+                if (Settings.Secure.getInt(view.context.contentResolver, Settings.Secure.LOCATION_MODE,
+                                Settings.Secure.LOCATION_MODE_OFF) == Settings.Secure.LOCATION_MODE_OFF) {
+                    Toast.makeText(view.context, R.string.tethering_temp_hotspot_location, Toast.LENGTH_LONG).show()
+                    try {
+                        view.context.startActivity(Intent(Settings.ACTION_LOCATION_SOURCE_SETTINGS))
+                    } catch (exc: ActivityNotFoundException) {
+                        exc.printStackTrace()
+                    }
+                    return
+                }
+                context.startForegroundService(Intent(context, LocalOnlyHotspotService::class.java))
             }
         }
     }

mobile/src/main/res/values-zh-rCN/strings.xml

@@ -29,6 +29,7 @@
     <string name="repeater_failure_reason_no_service_requests">未添加服务请求</string>
 
     <string name="tethering_temp_hotspot">临时 WLAN 热点</string>
+    <string name="tethering_temp_hotspot_location">使用临时热点需要打开位置服务。</string>
     <string name="tethering_temp_hotspot_failure">打开热点失败 (原因：%s)</string>
     <string name="tethering_temp_hotspot_failure_no_channel">无频段</string>
     <string name="tethering_temp_hotspot_failure_generic">通用错误</string>

mobile/src/main/res/values/strings.xml

@@ -40,6 +40,7 @@
     <string name="repeater_failure_reason_no_service_requests">no service requests added</string>
 
     <string name="tethering_temp_hotspot">Temporary Wi\u2011Fi hotspot</string>
+    <string name="tethering_temp_hotspot_location">Temporary hotspot requires location to be turned on.</string>
     <string name="tethering_temp_hotspot_failure">Failed to start hotspot (reason: %s)</string>
     <string name="tethering_temp_hotspot_failure_no_channel">no channel</string>
     <string name="tethering_temp_hotspot_failure_generic">generic error</string>