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 = {

[Felix Dahlke, 2017/01/30 16:24:47]

Why is this an array? Looks like there's just a single string, so I'd say let's
simplify it. If we need to check for multiple different regexps later (I hope we
can avoid it though), we can still turn this into an array.

[diegocarloslima, 2017/01/30 17:12:33]

Acknowledged.

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