Issue 4772 - Add temporary fix for removing unsupported filters

src/org/adblockplus/sbrowser/contentblocker/engine/Subscriptions.java

Index: src/org/adblockplus/sbrowser/contentblocker/engine/Subscriptions.java
===================================================================
--- a/src/org/adblockplus/sbrowser/contentblocker/engine/Subscriptions.java
+++ b/src/org/adblockplus/sbrowser/contentblocker/engine/Subscriptions.java
@@ -36,16 +36,19 @@ import android.util.Log;
  * This class holds all listed subscriptions and manages the subscription
  * aggregation cache folder.
  */
 final class Subscriptions
 {
   private static final String TAG = Subscriptions.class.getSimpleName();
   private static final String[] USER_SUBSCRIPTIONS =
   { Engine.USER_FILTERS_TITLE, Engine.USER_EXCEPTIONS_TITLE };
+  private static final String[] UNSUPPORTED_FILTERS_REGEX = {
+      "^(\\|\\$|\\|\\|\\$|@@\\|\\$|@@\\|\\|\\$).*" // Filters that begin with '|$' , '||$' , '@@|$' or '@@||$'
+  };
   private final HashMap<String, Subscription> subscriptions = new HashMap<String, Subscription>();
 
   private final Engine engine;
   private final File subscriptionFolder;
   private final File cacheFolder;
   private final boolean wasUnitialized;
 
   private Subscriptions(final Engine engine, final File appFolder, final File cacheFolder)
@@ -181,26 +184,47 @@ final class Subscriptions
     final BufferedWriter w = new BufferedWriter(
         new OutputStreamWriter(new FileOutputStream(output), "UTF-8"));
     try
     {
       Log.d(TAG, "Writing " + filters.size() + " filters");
       Engine.writeFilterHeaders(w);
       for (final String filter : filters)
       {
-        w.write(filter);
-        w.write('\n');
+        // This is a temporary fix to not write filters that might crash Samsung Internet
+        // See https://issues.adblockplus.org/ticket/4772
+        if (!isFilterUnsupported(filter))

[anton, 2017/01/09 09:54:43]

it would be better to have positive condition instead of double negative, f.e.
isFilterSupported()

[diegocarloslima, 2017/01/19 13:16:42]

Acknowledged.

+        {
+          w.write(filter);
+          w.write('\n');
+        }
+        else
+        {
+          Log.d(TAG, "Ignoring unsupported filter: " + filter);
+        }
       }
     }
     finally
     {
       w.close();
     }
   }
 
+  private static boolean isFilterUnsupported(String filter)
+  {
+    for (final String unsupportedFilterRegex : UNSUPPORTED_FILTERS_REGEX)
+    {
+      if (filter.matches(unsupportedFilterRegex))
+      {
+        return true;
+      }
+    }
+    return false;
+  }
+
   public Subscription add(final Subscription sub)
   {
     final String id = sub.getId();
     if (!this.subscriptions.containsKey(id))
     {
       this.subscriptions.put(id, sub);
       return sub;
     }