AU: Include the old/new kernel/rootfs size/hash in the update metadata.

omaha_hash_calculator.h

 // Copyright (c) 2009 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.
 
 #ifndef CHROMEOS_PLATFORM_UPDATE_ENGINE_OMAHA_HASH_CALCULATOR_H__
 #define CHROMEOS_PLATFORM_UPDATE_ENGINE_OMAHA_HASH_CALCULATOR_H__
 
 #include <string>
 #include <vector>
+
 #include <openssl/sha.h>
-#include "base/basictypes.h"
-#include "base/logging.h"
+#include <base/basictypes.h>
+#include <base/logging.h>
 
 // Omaha uses base64 encoded SHA-256 as the hash. This class provides a simple
 // wrapper around OpenSSL providing such a formatted hash of data passed in.
 // The methods of this class must be called in a very specific order: First the
 // ctor (of course), then 0 or more calls to Update(), then Finalize(), then 0
 // or more calls to hash().
 
 namespace chromeos_update_engine {
 
 class OmahaHashCalculator {
  public:
   OmahaHashCalculator();
 
   // Update is called with all of the data that should be hashed in order.
   // Update will read |length| bytes of |data|.
   // Returns true on success.
   bool Update(const char* data, size_t length);
 
+  // Updates the hash with up to |length| bytes of data from |file|. If |length|
+  // is negative, reads in and updates with the whole file. Returns the number
+  // of bytes that the hash was updated with, or -1 on error.
+  off_t UpdateFile(const std::string& name, off_t length);
+
   // Call Finalize() when all data has been passed in. This method tells
   // OpenSSl that no more data will come in and base64 encodes the resulting
   // hash.
   // Returns true on success.
   bool Finalize();
 
   // Gets the hash. Finalize() must have been called.
   const std::string& hash() const {
     DCHECK(!hash_.empty()) << "Call Finalize() first";
     return hash_;
@@ skipping 31 matching lines @@
   bool valid_;
 
   // The hash state used by OpenSSL
   SHA256_CTX ctx_;
   DISALLOW_COPY_AND_ASSIGN(OmahaHashCalculator);
 };
 
 }  // namespace chromeos_update_engine
 
 #endif  // CHROMEOS_PLATFORM_UPDATE_ENGINE_OMAHA_HASH_CALCULATOR_H__