diff --git a/utils.h b/utils.h
new file mode 100644
index 0000000..e475783
--- /dev/null
+++ b/utils.h
@@ -0,0 +1,184 @@
+// 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>
+#include "update_engine/action.h"
+#include "update_engine/action_processor.h"
+
+namespace chromeos_update_engine {
+
+namespace utils {
+
+// Returns the entire contents of the file at path. Returns true on success.
+bool ReadFile(const std::string& path, std::vector<char>* out);
+bool ReadFileToString(const std::string& path, std::string* out);
+
+std::string ErrnoNumberAsString(int err);
+
+// Strips duplicate slashes, and optionally removes all trailing slashes.
+// Does not compact /./ or /../.
+std::string NormalizePath(const std::string& path, bool strip_trailing_slash);
+
+// 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);
+
+// 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);
+
+// 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;
+
+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 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
+// or something with equivalent funcionality to interpret those.
+const std::string BootDevice();
+
+}  // namespace utils
+
+// Class to unmount FS when object goes out of scope
+class ScopedFilesystemUnmounter {
+ public:
+  explicit ScopedFilesystemUnmounter(const std::string& mountpoint)
+      : mountpoint_(mountpoint) {}
+  ~ScopedFilesystemUnmounter() {
+    utils::UnmountFilesystem(mountpoint_);
+  }
+ private:
+  const std::string mountpoint_;
+};
+
+// Utility class to close a file descriptor
+class ScopedFdCloser {
+ public:
+  explicit ScopedFdCloser(int* fd) : fd_(fd), should_close_(true) {}
+  void set_should_close(bool should_close) { should_close_ = should_close; }
+  ~ScopedFdCloser() {
+    if (!should_close_)
+      return;
+    if (fd_ && (*fd_ >= 0)) {
+      close(*fd_);
+      *fd_ = -1;
+    }
+  }
+ private:
+  int* fd_;
+  bool should_close_;
+};
+
+// A little object to call ActionComplete on the ActionProcessor when
+// it's destructed.
+class ScopedActionCompleter {
+ public:
+  explicit ScopedActionCompleter(ActionProcessor* processor,
+                                 AbstractAction* action)
+      : processor_(processor),
+        action_(action),
+        success_(false),
+        should_complete_(true) {}
+  ~ScopedActionCompleter() {
+    if (should_complete_)
+      processor_->ActionComplete(action_, success_);
+  }
+  void set_success(bool success) {
+    success_ = success;
+  }
+  void set_should_complete(bool should_complete) {
+    should_complete_ = should_complete;
+  }
+ private:
+  ActionProcessor* processor_;
+  AbstractAction* action_;
+  bool success_;
+  bool should_complete_;
+  DISALLOW_COPY_AND_ASSIGN(ScopedActionCompleter);
+};
+
+}  // namespace chromeos_update_engine
+
+#define TEST_AND_RETURN_FALSE_ERRNO(_x)                                        \
+  do {                                                                         \
+    bool _success = (_x);                                                      \
+    if (!_success) {                                                           \
+      std::string _msg =                                                       \
+          chromeos_update_engine::utils::ErrnoNumberAsString(errno);           \
+      LOG(ERROR) << #_x " failed: " << _msg;                                   \
+      return false;                                                            \
+    }                                                                          \
+  } while (0)
+
+#define TEST_AND_RETURN_FALSE(_x)                                              \
+  do {                                                                         \
+    bool _success = (_x);                                                      \
+    if (!_success) {                                                           \
+      LOG(ERROR) << #_x " failed.";                                            \
+      return false;                                                            \
+    }                                                                          \
+  } while (0)
+
+#define TEST_AND_RETURN_ERRNO(_x)                                              \
+  do {                                                                         \
+    bool _success = (_x);                                                      \
+    if (!_success) {                                                           \
+      std::string _msg =                                                       \
+          chromeos_update_engine::utils::ErrnoNumberAsString(errno);           \
+      LOG(ERROR) << #_x " failed: " << _msg;                                   \
+      return;                                                                  \
+    }                                                                          \
+  } while (0)
+
+#define TEST_AND_RETURN(_x)                                                    \
+  do {                                                                         \
+    bool _success = (_x);                                                      \
+    if (!_success) {                                                           \
+      LOG(ERROR) << #_x " failed.";                                            \
+      return;                                                                  \
+    }                                                                          \
+  } while (0)
+
+
+
+#endif  // CHROMEOS_PLATFORM_UPDATE_ENGINE_UTILS_H__