Adds Exponential backoff for provisioning results

ImsService initialization can take longer than
telephoyn initialization in some cases, which causes
ImsConfig queries to return with an error. This change
adds an exponential backoff for querying provisioning
results from ImsConfig if we get an error during
initialization.

Bug: 64540800
Test: Manual
Change-Id: I2193e42736994de3cce6fb24ee1dcc9e936bebf0

1 files changed, 60 insertions, 5 deletions

diff --git a/src/java/com/android/ims/ImsManager.java b/src/java/com/android/ims/ImsManager.java
index ccb602bb..5319ea42 100644
--- a/src/java/com/android/ims/ImsManager.java
+++ b/src/java/com/android/ims/ImsManager.java
@@ -21,7 +21,9 @@ import android.content.Context;
 import android.content.Intent;
 import android.net.Uri;
 import android.os.AsyncTask;
+import android.os.Handler;
 import android.os.IBinder;
+import android.os.Looper;
 import android.os.Message;
 import android.os.Parcel;
 import android.os.PersistableBundle;
@@ -50,6 +52,7 @@ import com.android.ims.internal.IImsUt;
 import com.android.ims.internal.ImsCallSession;
 import com.android.ims.internal.IImsConfig;
 import com.android.internal.annotations.VisibleForTesting;
+import com.android.internal.telephony.ExponentialBackoff;
 
 import java.io.FileDescriptor;
 import java.io.PrintWriter;
@@ -227,6 +230,17 @@ public class ImsManager {
     private ConcurrentLinkedDeque<ImsReasonInfo> mRecentDisconnectReasons =
             new ConcurrentLinkedDeque<>();
 
+    // Exponential backoff for provisioning cache update. May be null for instances of ImsManager
+    // that are not on a thread supporting a looper.
+    private ExponentialBackoff mProvisionBackoff;
+    // Initial Provisioning check delay in ms
+    private static final long BACKOFF_INITIAL_DELAY_MS = 500;
+    // Max Provisioning check delay in ms (5 Minutes)
+    private static final long BACKOFF_MAX_DELAY_MS = 300000;
+    // Multiplier for exponential delay
+    private static final int BACKOFF_MULTIPLIER = 2;
+
+
     /**
      * Gets a manager instance.
      *
@@ -1183,9 +1197,9 @@ public class ImsManager {
         }
     }
 
-    private class AsyncUpdateProvisionedValues extends AsyncTask<Void, Void, Void> {
+    private class AsyncUpdateProvisionedValues extends AsyncTask<Void, Void, Boolean> {
         @Override
-        protected Void doInBackground(Void... params) {
+        protected Boolean doInBackground(Void... params) {
             // disable on any error
             setVolteProvisionedProperty(false);
             setWfcProvisionedProperty(false);
@@ -1209,18 +1223,40 @@ public class ImsManager {
                 }
             } catch (ImsException ie) {
                 Rlog.e(TAG, "AsyncUpdateProvisionedValues error: ", ie);
+                return false;
             }
 
-            return null;
+            return true;
+        }
+
+        @Override
+        protected void onPostExecute(Boolean completed) {
+            if (mProvisionBackoff == null) {
+                return;
+            }
+            if (!completed) {
+                mProvisionBackoff.notifyFailed();
+            } else {
+                mProvisionBackoff.stop();
+            }
         }
 
+        /**
+         * Will return with config value or throw an ImsException if we receive an error from
+         * ImsConfig for that value.
+         */
         private boolean getProvisionedBool(ImsConfig config, int item) throws ImsException {
+            int value = config.getProvisionedValue(item);
+            if (value == ImsConfig.FeatureValueConstants.ERROR) {
+                throw new ImsException("getProvisionedBool failed with error for item: " + item,
+                        ImsReasonInfo.CODE_LOCAL_INTERNAL_ERROR);
+            }
             return config.getProvisionedValue(item) == ImsConfig.FeatureValueConstants.ON;
         }
     }
 
-    /** Asynchronously get VoLTE, WFC, VT provisioning statuses */
-    private void updateProvisionedValues() {
+    // used internally only, use #updateProvisionedValues instead.
+    private void handleUpdateProvisionedValues() {
         if (getBooleanCarrierConfigForSlot(
                 CarrierConfigManager.KEY_CARRIER_VOLTE_PROVISIONING_REQUIRED_BOOL)) {
 
@@ -1229,6 +1265,20 @@ public class ImsManager {
     }
 
     /**
+     * Asynchronously get VoLTE, WFC, VT provisioning statuses. If ImsConfig is not available, we
+     * will retry with exponential backoff.
+     */
+    private void updateProvisionedValues() {
+        // Start trying to receive provisioning status after BACKOFF_INITIAL_DELAY_MS.
+        if (mProvisionBackoff != null) {
+            mProvisionBackoff.start();
+        } else {
+            // bypass and launch async thread once without backoff.
+            handleUpdateProvisionedValues();
+        }
+    }
+
+    /**
      * Sync carrier config and user settings with ImsConfig.
      *
      * @param context for the manager object
@@ -1436,6 +1486,11 @@ public class ImsManager {
                 com.android.internal.R.bool.config_dynamic_bind_ims);
         mConfigManager = (CarrierConfigManager) context.getSystemService(
                 Context.CARRIER_CONFIG_SERVICE);
+        if (Looper.getMainLooper() != null) {
+            mProvisionBackoff = new ExponentialBackoff(BACKOFF_INITIAL_DELAY_MS,
+                    BACKOFF_MAX_DELAY_MS, BACKOFF_MULTIPLIER,
+                    new Handler(Looper.getMainLooper()), this::handleUpdateProvisionedValues);
+        }
         createImsService();
     }