check DOS format bug

src/com/bytezone/diskbrowser/dos/DosDisk.java

@@ -395,7 +395,8 @@ public class DosDisk extends AbstractFormattedDisk
     if (debug)
       System.out.printf ("Catalog blocks: %s%n", catalogBlocks);
 
-    disk.setDosVersion (version);
+    if (catalogBlocks > 0)
+      disk.setDosVersion (version);
     return catalogBlocks;
   }
 
@@ -403,6 +404,13 @@ public class DosDisk extends AbstractFormattedDisk
   private static int countCatalogBlocks (AppleDisk disk, byte[] buffer)
   // ---------------------------------------------------------------------------------//
   {
+    if (!disk.isValidAddress (buffer[1], buffer[2]))
+    {
+      if (debug)
+        System.out.printf ("Invalid address1: %02X %02X%n", buffer[1], buffer[2]);
+      return 0;
+    }
+
     DiskAddress catalogStart = disk.getDiskAddress (buffer[1], buffer[2]);
     DiskAddress da = disk.getDiskAddress (catalogStart.getBlockNo ());
     List<DiskAddress> catalogAddresses = new ArrayList<> ();
@@ -430,14 +438,13 @@ public class DosDisk extends AbstractFormattedDisk
       if (!disk.isValidAddress (buffer[1], buffer[2]))
       {
         if (debug)
-          System.out.printf ("Invalid address: %02X %02X%n", buffer[1], buffer[2]);
+          System.out.printf ("Invalid address2: %02X %02X%n", buffer[1], buffer[2]);
         return catalogAddresses.size ();
       }
 
       catalogAddresses.add (da);
 
       da = disk.getDiskAddress (buffer[1], buffer[2]);
-
     } while (!da.isZero ());
 
     if (debug)

src/com/bytezone/diskbrowser/pascal/PascalDisk.java

@@ -108,7 +108,6 @@ public class PascalDisk extends AbstractFormattedDisk
       addresses.add (disk.getDiskAddress (i));
     buffer = disk.readBlocks (addresses);
 
-    // loop through each catalog entry (what if there are deleted files?)
     for (int i = 1; i <= volumeEntry.totalFiles; i++)
     {
       int ptr = i * CATALOG_ENTRY_SIZE;
@@ -179,11 +178,11 @@ public class PascalDisk extends AbstractFormattedDisk
     }
 
     int blocks = Utility.intValue (buffer[14], buffer[15]);
-    if (blocks > 280)
+    if (blocks != 280 && blocks != 1600)
     {
       if (debug)
         System.out.printf ("Blocks > 280: %d%n", blocks);
-      //      return false;
+      return false;
     }
 
     List<DiskAddress> addresses = new ArrayList<> ();