AU: Try delta updates first, then full updates

src/platform/update_engine/utils.h

 // Copyright (c) 2009 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 CHROMEOS_PLATFORM_UPDATE_ENGINE_UTILS_H__
 #define CHROMEOS_PLATFORM_UPDATE_ENGINE_UTILS_H__
 
 #include <set>
 #include <string>
 #include <vector>
@@ skipping 20 matching lines @@
 
 // Returns true if the file exists for sure. Returns false if it doesn't exist,
 // or an error occurs.
 bool FileExists(const char* path);
 
 // The last 6 chars of path must be XXXXXX. They will be randomly changed
 // and a non-existent path will be returned. Intentionally makes a copy
 // of the string passed in.
 // NEVER CALL THIS FUNCTION UNLESS YOU ARE SURE
 // THAT YOUR PROCESS WILL BE THE ONLY THING WRITING FILES IN THIS DIRECTORY.
-std::string TempFilename(string path);
+std::string TempFilename(std::string path);
 
 // Deletes a directory and all its contents synchronously. Returns true
 // on success. This may be called with a regular file--it will just unlink it.
 // This WILL cross filesystem boundaries.
 bool RecursiveUnlinkDir(const std::string& path);
 
 // Synchronously mount or unmount a filesystem. Return true on success.
 // Mounts as ext3 with default options.
-bool MountFilesystem(const string& device, const string& mountpoint);
-bool UnmountFilesystem(const string& mountpoint);
+bool MountFilesystem(const std::string& device, const std::string& mountpoint);
+bool UnmountFilesystem(const std::string& mountpoint);
 
 // Log a string in hex to LOG(INFO). Useful for debugging.
 void HexDumpArray(const unsigned char* const arr, const size_t length);
 inline void HexDumpString(const std::string& str) {
   HexDumpArray(reinterpret_cast<const unsigned char*>(str.data()), str.size());
 }
 inline void HexDumpVector(const std::vector<char>& vect) {
   HexDumpArray(reinterpret_cast<const unsigned char*>(&vect[0]), vect.size());
 }
 
-extern const string kStatefulPartition;
+extern const char* const kStatefulPartition;
 
 bool StringHasSuffix(const std::string& str, const std::string& suffix);
 bool StringHasPrefix(const std::string& str, const std::string& prefix);
 
 template<typename KeyType, typename ValueType>
 bool MapContainsKey(const std::map<KeyType, ValueType>& m, const KeyType& k) {
   return m.find(k) != m.end();
 }
+template<typename KeyType>
+bool SetContainsKey(const std::set<KeyType>& s, const KeyType& k) {
+  return s.find(k) != s.end();
+}
 
 template<typename ValueType>
 std::set<ValueType> SetWithValue(const ValueType& value) {
   std::set<ValueType> ret;
   ret.insert(value);
   return ret;
 }
 
 // Returns the currently booted device. "/dev/sda1", for example.
 // This will not interpret LABEL= or UUID=. You'll need to use findfs
@@ skipping 98 matching lines @@
     bool _success = (_x);                                                      \
     if (!_success) {                                                           \
       LOG(ERROR) << #_x " failed.";                                            \
       return;                                                                  \
     }                                                                          \
   } while (0)
 
 
 
 #endif  // CHROMEOS_PLATFORM_UPDATE_ENGINE_UTILS_H__