Start refactoring to reduce executable type knowledge.

courgette/courgette.h

-// 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.
 
 #ifndef COURGETTE_COURGETTE_H_
 #define COURGETTE_COURGETTE_H_
 
 #include <stddef.h>   // Required to define size_t on GCC
 
 #include "base/file_path.h"
 
@@ skipping 31 matching lines @@
   C_STREAM_NOT_CONSUMED = 21,     // Stream has extra data, is expected to be
                                   // used up.
   C_SERIALIZATION_FAILED = 22,    //
   C_DESERIALIZATION_FAILED = 23,  //
   C_INPUT_NOT_RECOGNIZED = 24,    // Unrecognized input (not an executable).
   C_DISASSEMBLY_FAILED = 25,      //
   C_ASSEMBLY_FAILED = 26,         //
   C_ADJUSTMENT_FAILED = 27,       //
 };
 
+// What type of executable is something
+// Generally corresponds to CourgettePatchFile::TransformationMethodId
+enum ExecutableType {
+  UNKNOWN,
+  WIN32_X86
+};
+
 class SinkStream;
 class SinkStreamSet;
 class SourceStream;
 class SourceStreamSet;
 
 class AssemblyProgram;
 class EncodedProgram;
 
 // Applies the patch to the bytes in |old| and writes the transformed ensemble
 // to |output|.
@@ skipping 10 matching lines @@
 Status ApplyEnsemblePatch(const FilePath::CharType* old_file_name,
                           const FilePath::CharType* patch_file_name,
                           const FilePath::CharType* new_file_name);
 
 // Generates a patch that will transform the bytes in |old| into the bytes in
 // |target|.
 // Returns C_OK unless something when wrong (unexpected).
 Status GenerateEnsemblePatch(SourceStream* old, SourceStream* target,
                              SinkStream* patch);
 
-// Parses a Windows 32-bit 'Portable Executable' format file from memory,
-// storing the pointer to the AssemblyProgram in |*output|.
+// Detects the type of an executable, and returns UNKNOWN if it cannot
+// be parsed.
+ExecutableType DetectExecutableType(const void* buffer, size_t length);
+
+// Attempts to detect the type of executable, and parse it with the
+// appropriate tools, storing the pointer to the AssemblyProgram in |*output|.
 // Returns C_OK if successful, otherwise returns an error status and sets
 // |*output| to NULL.
-Status ParseWin32X86PE(const void* buffer, size_t length,
-                       AssemblyProgram** output);
+Status ParseDetectedExecutable(const void* buffer, size_t length,
+                               AssemblyProgram** output);
 
 // Converts |program| into encoded form, returning it as |*output|.
 // Returns C_OK if succeeded, otherwise returns an error status and
 // sets |*output| to NULL
 Status Encode(AssemblyProgram* program, EncodedProgram** output);
 
 
 // Serializes |encoded| into the stream set.
 // Returns C_OK if succeeded, otherwise returns an error status.
 Status WriteEncodedProgram(EncodedProgram* encoded, SinkStreamSet* sink);
@@ skipping 13 matching lines @@
 
 // Used to free an EncodedProgram returned by other APIs.
 void DeleteEncodedProgram(EncodedProgram* encoded);
 
 // Adjusts |program| to look more like |model|.
 //
 Status Adjust(const AssemblyProgram& model, AssemblyProgram *program);
 
 }  // namespace courgette
 #endif  // COURGETTE_COURGETTE_H_