Allow overlap between "pure" fmap areas

utility/pack_firmware_image

 #!/usr/bin/env python2.6
 
 # Copyright (c) 2011 The Chromium OS Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 import os
 import re
 import struct
 import subprocess
@@ skipping 102 matching lines @@
     firmware_image.seek(self.offset)
     firmware_image.write(blob)
 
 
 class EntryFmapArea(Entry):
 
   def __init__(self, **kwargs):
     Entry._CheckFields(kwargs, ('flags',))
     super(EntryFmapArea, self).__init__(**kwargs)
 
+  def Pack(self, firmware_image, entries):
+    pass
+
 
 class EntryBlob(EntryFmapArea):
 
   def __init__(self, **kwargs):
     Entry._CheckFields(kwargs, ('path',))
     super(EntryBlob, self).__init__(**kwargs)
 
   def Pack(self, firmware_image, entries):
     size = os.stat(self.path).st_size
     if size > self.length:
-        raise PackError('blob too large: %d > %d' % (size, self.length))
+      raise PackError('blob too large: %s: %d > %d' %
+          (self.path, size, self.length))
     if size == 0: # special case for files like /dev/zero
       size = self.length
     with open(self.path, 'rb') as blob_image:
       firmware_image.seek(self.offset)
       firmware_image.write(blob_image.read(size))
 
 
 class EntryKeyBlock(EntryFmapArea):
 
   stdout = None
@@ skipping 63 matching lines @@
     return expr[1:-1] # if it is quoted, always interpreted as string literals
   try:
     return int(expr, 0)
   except ValueError:
     return expr # if not a number, interpret as string literals
 
 
 def pack_firmware_image(entries, output_path, image_size):
   entries = sorted(entries, key=lambda e: e.offset)
   for e1, e2 in zip(entries, entries[1:]):
-    if e1.IsOverlapped(e2):
+    # Allow overlap between "pure" fmap areas, but not any of its subclasses
+    # Here we exploit the fact that Entry is a new-style class
+    if (e1.IsOverlapped(e2) and
+        type(e1) is not EntryFmapArea and type(e2) is not EntryFmapArea):
       raise PackError('overlapped entries: [%08x:%08x], [%08x:%08x]' %
           (e1.offset, e1.offset + e1.length, e2.offset, e2.offset + e2.length))
 
   with open(output_path, 'wb') as firmware_image:
     # resize firmware image file
     firmware_image.seek(0)
     firmware_image.write('\0' * image_size)
 
     for entry in entries:
       entry.Pack(firmware_image, entries)
@@ skipping 29 matching lines @@
       raise ConfigError('undefined variable: %s' % varname)
     _Info('%s = %s' % (varname, repr(env[varname])))
 
   pack_firmware_image(env['ENTRIES'], env['OUTPUT'], env['SIZE'])
 
   sys.exit(0)
 
 
 if __name__ == '__main__':
   main()