From d8d6992c07a3722c30d658e728caeb796f4847de Mon Sep 17 00:00:00 2001
From: Jeff Sharkey <jsharkey@android.com>
Date: Thu, 25 Jun 2020 20:13:07 -0600
Subject: [PATCH] Fix a Sms7BitEncodingTranslator threading issue, since
 translate() method can easily race when called by multiple threads.

Bug: 160733170
Test: Sanity; Telephony unit tests; hard to reproduce
Change-Id: If8347a27a79351e84060c9a35e1cc9efd468f7a0
Merged-In: If8347a27a79351e84060c9a35e1cc9efd468f7a0
(cherry picked from commit 131781145dbd7a6f65a759f932abb48aca652ace)
---
 .../telephony/Sms7BitEncodingTranslator.java  | 22 +++++++++++++------
 1 file changed, 15 insertions(+), 7 deletions(-)

diff --git a/telephony/java/com/android/internal/telephony/Sms7BitEncodingTranslator.java b/telephony/java/com/android/internal/telephony/Sms7BitEncodingTranslator.java
index 3bd8cdd23df36..f8ab87d042ebd 100644
--- a/telephony/java/com/android/internal/telephony/Sms7BitEncodingTranslator.java
+++ b/telephony/java/com/android/internal/telephony/Sms7BitEncodingTranslator.java
@@ -65,13 +65,7 @@ public class Sms7BitEncodingTranslator {
             return "";
         }
 
-        if (!mIs7BitTranslationTableLoaded) {
-            mTranslationTableCommon = new SparseIntArray();
-            mTranslationTableGSM = new SparseIntArray();
-            mTranslationTableCDMA = new SparseIntArray();
-            load7BitTranslationTableFromXml();
-            mIs7BitTranslationTableLoaded = true;
-        }
+        ensure7BitTranslationTableLoaded();
 
         if ((mTranslationTableCommon != null && mTranslationTableCommon.size() > 0) ||
                 (mTranslationTableGSM != null && mTranslationTableGSM.size() > 0) ||
@@ -115,6 +109,8 @@ public class Sms7BitEncodingTranslator {
          */
         int translation = -1;
 
+        ensure7BitTranslationTableLoaded();
+
         if (mTranslationTableCommon != null) {
             translation = mTranslationTableCommon.get(c, -1);
         }
@@ -155,6 +151,18 @@ public class Sms7BitEncodingTranslator {
         }
     }
 
+    private static void ensure7BitTranslationTableLoaded() {
+        synchronized (Sms7BitEncodingTranslator.class) {
+            if (!mIs7BitTranslationTableLoaded) {
+                mTranslationTableCommon = new SparseIntArray();
+                mTranslationTableGSM = new SparseIntArray();
+                mTranslationTableCDMA = new SparseIntArray();
+                load7BitTranslationTableFromXml();
+                mIs7BitTranslationTableLoaded = true;
+            }
+        }
+    }
+
     /**
      * Load the whole translation table file from the framework resource
      * encoded in XML.