From da023cc43ff316805c0b3af2b38b67b2a0000bf3 Mon Sep 17 00:00:00 2001
From: Marijn Suijten <marijns95@gmail.com>
Date: Fri, 16 Oct 2020 12:13:44 +0200
Subject: [PATCH] ModemConfig: Convert getProviders one-time-init to lazyinit

Lazyinit allows a non-nullable to be null "temporarily" while it is
initialized outside of a constructor. This is useful in android
scenarios where initialization usually happens in onCreate().

Note that it is not really safe. The compiler doesn't do any checks or
use annotations to understand that this value should be initialized in
onCreate, nor does it fail compilation if it is never initialized at
all or used before initialization. After all `providers` remains a
`var`iable, not a `val`ue. In hindsight `lateinit` is simply a free pass
to circumvent compile-time null checks, and is best avoided.

Signed-off-by: Marijn Suijten <marijns95@gmail.com>
---
 .../modemconfig/ModemConfigService.kt         | 21 ++++++++-----------
 1 file changed, 9 insertions(+), 12 deletions(-)

diff --git a/ModemConfig/src/com/sony/opentelephony/modemconfig/ModemConfigService.kt b/ModemConfig/src/com/sony/opentelephony/modemconfig/ModemConfigService.kt
index 11dd354..036ee8d 100644
--- a/ModemConfig/src/com/sony/opentelephony/modemconfig/ModemConfigService.kt
+++ b/ModemConfig/src/com/sony/opentelephony/modemconfig/ModemConfigService.kt
@@ -20,7 +20,6 @@ import android.app.Notification
 import android.app.NotificationChannel
 import android.app.NotificationManager
 import android.app.Service
-import android.content.Context
 import android.content.Intent
 import android.os.IBinder
 import android.telephony.SubscriptionInfo
@@ -56,24 +55,20 @@ class ModemConfigService : Service() {
         fun specificity() = listOfNotNull(mcc, mnc, gid1, imsi, sp).count()
     }
 
-    // TODO: Do a lateinit here?
-    private /*lateinit*/ var providers: List<ProviderFilter>? = null
+    private lateinit var providers: List<ProviderFilter>
 
     private val notificationManager: NotificationManager by lazy {
         getSystemService(NotificationManager::class.java)
         ?: throw Exception("Expected NotificationManager, got null")
     }
 
-    private fun getProviders(context: Context): List<ProviderFilter> {
-        if (providers != null)
-            return providers!!
-
+    private fun parseProviders(): List<ProviderFilter> {
         val list = arrayListOf<ProviderFilter>()
 
         val currentMap = hashMapOf<String, String>()
         var simConfigId: String? = null
 
-        context.resources.getXml(R.xml.service_provider_sim_configs).use { xml ->
+        this.resources.getXml(R.xml.service_provider_sim_configs).use { xml ->
             while (xml.next() != XmlPullParser.END_DOCUMENT) {
                 if (xml.eventType == XmlPullParser.END_TAG &&
                     xml.name == "service_provider_sim_config") {
@@ -111,13 +106,12 @@ class ModemConfigService : Service() {
         }
 
         list.sortByDescending { it.specificity() }
-        providers = list
         return list
     }
 
     private fun String.cleanString() = replace(newlineMatch, "").trim()
 
-    private fun findConfigurationName(context: Context, tm: TelephonyManager): String? {
+    private fun findConfigurationName(tm: TelephonyManager): String? {
         val operator = tm.simOperator
         if (operator.isNullOrEmpty()) {
             Log.d(TAG, "Operator is null or empty")
@@ -137,7 +131,7 @@ class ModemConfigService : Service() {
         if (VERBOSE) Log.v(TAG, "Matching providers against: $sp $mcc/$mnc, imsi: $imsi" +
                                 ", gid: $gid1")
 
-        val result = getProviders(context).firstOrNull f@{ info ->
+        val result = providers.firstOrNull f@{ info ->
             if (info.mcc != null && info.mcc != mcc)
                 return@f false
             if (info.mnc != null && info.mnc != mnc)
@@ -184,7 +178,7 @@ class ModemConfigService : Service() {
 
         val globalTm = getSystemService(TelephonyManager::class.java)
         val tm = globalTm!!.createForSubscriptionId(sub.subscriptionId)
-        val name = findConfigurationName(this, tm)
+        val name = findConfigurationName(tm)
 
         val notificationText = if (name != null) {
             val prop = "persist.somc.cust.modem${sub.simSlotIndex}"
@@ -223,6 +217,9 @@ class ModemConfigService : Service() {
 
     override fun onCreate() {
         Log.e(TAG, "Starting")
+
+        providers = parseProviders()
+
         val sm = getSystemService(SubscriptionManager::class.java)
                  ?: throw Exception("Expected SubscriptionManager, got null")