1 files changed, 87 insertions, 0 deletions
diff --git a/cros_utils/file_utils.py b/cros_utils/file_utils.py
new file mode 100644
index 00000000..777e6251
--- /dev/null
+++ b/cros_utils/file_utils.py
@@ -0,0 +1,87 @@
+# Copyright 2011 Google Inc. All Rights Reserved.
+"""Utilities for operations on files."""
+
+from __future__ import print_function
+
+import errno
+import os
+import shutil
+import command_executer
+
+
+class FileUtils(object):
+  """Utilities for operations on files."""
+  _instance = None
+  DRY_RUN = False
+
+  @classmethod
+  def Configure(cls, dry_run):
+    cls.DRY_RUN = dry_run
+
+  def __new__(cls, *args, **kwargs):
+    if not cls._instance:
+      if cls.DRY_RUN:
+        cls._instance = super(FileUtils, cls).__new__(MockFileUtils, *args,
+                                                      **kwargs)
+      else:
+        cls._instance = super(FileUtils, cls).__new__(cls, *args, **kwargs)
+    return cls._instance
+
+  def Md5File(self, filename, log_level='verbose', _block_size=2**10):
+    command = 'md5sum %s' % filename
+    ce = command_executer.GetCommandExecuter(log_level=log_level)
+    ret, out, _ = ce.RunCommandWOutput(command)
+    if ret:
+      raise RuntimeError('Could not run md5sum on: %s' % filename)
+
+    return out.strip().split()[0]
+
+  def CanonicalizeChromeOSRoot(self, chromeos_root):
+    chromeos_root = os.path.expanduser(chromeos_root)
+    if os.path.isdir(os.path.join(chromeos_root, 'chromite')):
+      return chromeos_root
+    else:
+      return None
+
+  def ChromeOSRootFromImage(self, chromeos_image):
+    chromeos_root = os.path.join(
+        os.path.dirname(chromeos_image), '../../../../..')
+    return self.CanonicalizeChromeOSRoot(chromeos_root)
+
+  def MkDirP(self, path):
+    try:
+      os.makedirs(path)
+    except OSError as exc:
+      if exc.errno == errno.EEXIST:
+        pass
+      else:
+        raise
+
+  def RmDir(self, path):
+    shutil.rmtree(path, ignore_errors=True)
+
+  def WriteFile(self, path, contents):
+    with open(path, 'wb') as f:
+      f.write(contents)
+
+
+class MockFileUtils(FileUtils):
+  """Mock class for file utilities."""
+
+  def Md5File(self, filename, log_level='verbose', _block_size=2**10):
+    return 'd41d8cd98f00b204e9800998ecf8427e'
+
+  def CanonicalizeChromeOSRoot(self, chromeos_root):
+    return '/tmp/chromeos_root'
+
+  def ChromeOSRootFromImage(self, chromeos_image):
+    return '/tmp/chromeos_root'
+
+  def RmDir(self, path):
+    pass
+
+  def MkDirP(self, path):
+    pass
+
+  def WriteFile(self, path, contents):
+    pass