Start refactoring to reduce executable type knowledge.

courgette/ensemble.h

Index: courgette/ensemble.h
diff --git a/courgette/ensemble.h b/courgette/ensemble.h
index f907f9d9a62273a6bf88febd72b60d36b304d47b..e766782822c7897ab4abaf15425c417d8154eb2a 100644
--- a/courgette/ensemble.h
+++ b/courgette/ensemble.h
@@ -1,4 +1,4 @@
-// Copyright (c) 2009 The Chromium Authors. All rights reserved.
+// Copyright (c) 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
@@ -36,11 +36,14 @@ class PEInfo;
 //
 class Element {
  public:
-  enum Kind { WIN32_X86_WITH_CODE, WIN32_NOCODE };
+  Element(ExecutableType kind,
+          Ensemble* ensemble,
+          const Region& region,
+          PEInfo*info);
 
-  virtual ~Element() {}
+  virtual ~Element();
 
-  Kind kind() const { return kind_; }
+  ExecutableType kind() const { return kind_; }
   const Region& region() const { return region_; }
 
   // The name is used only for debugging and logging.
@@ -50,16 +53,14 @@ class Element {
   // containing Ensemble.
   size_t offset_in_ensemble() const;
 
-  // Some subclasses of Element might have a PEInfo.
-  virtual PEInfo* GetPEInfo() const { return NULL; }
-
- protected:
-  Element(Kind kind, Ensemble* ensemble, const Region& region);
+  // The ImageInfo for this executable
+  virtual PEInfo* GetImageInfo() const { return info_; }

[Michael Krebs, 2011/10/21 02:44:36]

You made the method name generic, while the return value is still PE-specific. 
Given the data is also PE-specific, I would think GetPEInfo() would be fine. 
...although this nit may be moot depending on what changes are made for ELF.

[dgarrett, 2011/10/21 18:24:59]

You are right, but this gets fixed in the next step of the refactor.

 
  private:
-  Kind kind_;
+  ExecutableType kind_;
   Ensemble* ensemble_;
   Region region_;
+  PEInfo *info_;
 
   DISALLOW_COPY_AND_ASSIGN(Element);
 };
@@ -139,7 +140,8 @@ struct CourgettePatchFile {
 
   static const uint32 kVersion = 20110216;
 
-  // Transformation method IDs.
+  // Transformation method IDs. These are embedded in generated files, so
+  // never remove or change an existing id.
   enum TransformationMethodId {
     T_COURGETTE_WIN32_X86 = 1,  // Windows 32 bit 'Portable Executable' x86.
   };