1 files changed, 404 insertions, 0 deletions
diff --git a/tensorflow/python/platform/default/_gfile.py b/tensorflow/python/platform/default/_gfile.py
new file mode 100644
index 0000000000..cfd25bdf90
--- /dev/null
+++ b/tensorflow/python/platform/default/_gfile.py
@@ -0,0 +1,404 @@
+"""File processing utilities."""
+
+import errno
+import functools
+import glob as _glob
+import os
+import shutil
+import threading
+
+
+class FileError(IOError):
+  """An error occurred while reading or writing a file."""
+
+
+class GOSError(OSError):
+  """An error occurred while finding a file or in handling pathnames."""
+
+
+class _GFileBase(object):
+  """Base I/O wrapper class.  Similar semantics to Python's file object."""
+
+  # pylint: disable=protected-access
+  def _error_wrapper(fn):
+    """Decorator wrapping GFileBase class method errors."""
+    @functools.wraps(fn)  # Preserve methods' __doc__
+    def wrap(self, *args, **kwargs):
+      try:
+        return fn(self, *args, **kwargs)
+      except ValueError, e:
+        # Sometimes a ValueError is raised, e.g., a read() on a closed file.
+        raise FileError(errno.EIO, e.message, self._name)
+      except IOError, e:
+        e.filename = self._name
+        raise FileError(e)
+      except OSError, e:
+        raise GOSError(e)
+    return wrap
+
+  def _synchronized(fn):
+    """Synchronizes file I/O for methods in GFileBase."""
+    @functools.wraps(fn)
+    def sync(self, *args, **kwargs):
+      # Sometimes a GFileBase method is called before the instance
+      # has been properly initialized.  Check that _locker is available.
+      if hasattr(self, '_locker'): self._locker.lock()
+      try:
+        return fn(self, *args, **kwargs)
+      finally:
+        if hasattr(self, '_locker'): self._locker.unlock()
+    return sync
+  # pylint: enable=protected-access
+
+  @_error_wrapper
+  def __init__(self, name, mode, locker):
+    """Create the GFileBase object with the given filename, mode, and locker.
+
+    Args:
+      name: string, the filename.
+      mode: string, the mode to open the file with (e.g. "r", "w", "a+").
+      locker: the thread locking object (e.g. _PythonLocker) for controlling
+        thread access to the I/O methods of this class.
+    """
+    self._name = name
+    self._mode = mode
+    self._locker = locker
+    self._fp = open(name, mode)
+
+  def __enter__(self):
+    """Make GFileBase usable with "with" statement."""
+    return self
+
+  def __exit__(self, unused_type, unused_value, unused_traceback):
+    """Make GFileBase usable with "with" statement."""
+    self.close()
+
+  @_error_wrapper
+  @_synchronized
+  def __del__(self):
+    # __del__ is sometimes called before initialization, in which
+    # case the object is not fully constructed.  Check for this here
+    # before trying to close the file handle.
+    if hasattr(self, '_fp'): self._fp.close()
+
+  @_error_wrapper
+  @_synchronized
+  def flush(self):
+    """Flush the underlying file handle."""
+    return self._fp.flush()
+
+  @property
+  @_error_wrapper
+  @_synchronized
+  def closed(self):
+    """Returns "True" if the file handle is closed.  Otherwise False."""
+    return self._fp.closed
+
+  @_error_wrapper
+  @_synchronized
+  def write(self, data):
+    """Write data to the underlying file handle.
+
+    Args:
+      data: The string to write to the file handle.
+    """
+    self._fp.write(data)
+
+  @_error_wrapper
+  @_synchronized
+  def writelines(self, seq):
+    """Write a sequence of strings to the underlying file handle."""
+    self._fp.writelines(seq)
+
+  @_error_wrapper
+  @_synchronized
+  def tell(self):
+    """Return the location from the underlying file handle.
+
+    Returns:
+      An integer location (which can be used in e.g., seek).
+    """
+    return self._fp.tell()
+
+  @_error_wrapper
+  @_synchronized
+  def seek(self, offset, whence=0):
+    """Seek to offset (conditioned on whence) in the underlying file handle.
+
+    Args:
+      offset: int, the offset within the file to seek to.
+      whence: 0, 1, or 2.  See python's seek() documentation for details.
+    """
+    self._fp.seek(offset, whence)
+
+  @_error_wrapper
+  @_synchronized
+  def truncate(self, new_size=None):
+    """Truncate the underlying file handle to new_size.
+
+    Args:
+      new_size: Size after truncation.  If None, the file handle is truncated
+      to 0 bytes.
+    """
+    self._fp.truncate(new_size)
+
+  @_error_wrapper
+  @_synchronized
+  def readline(self, max_length=-1):
+    """Read a single line (up to max_length) from the underlying file handle.
+
+    Args:
+      max_length: The maximum number of chsaracters to read.
+
+    Returns:
+      A string, including any newline at the end, or empty string if at EOF.
+    """
+    return self._fp.readline(max_length)
+
+  @_error_wrapper
+  @_synchronized
+  def readlines(self, sizehint=None):
+    """Read lines from the underlying file handle.
+
+    Args:
+      sizehint: See the python file.readlines() documentation.
+
+    Returns:
+      A list of strings from the underlying file handle.
+    """
+    if sizehint is not None:
+      return self._fp.readlines(sizehint)
+    else:
+      return self._fp.readlines()
+
+  def __iter__(self):
+    """Enable line iteration on the underlying handle (not synchronized)."""
+    return self
+
+  # Not synchronized
+  @_error_wrapper
+  def next(self):
+    """Enable line iteration on the underlying handle (not synchronized).
+
+    Returns:
+      An line iterator from the underlying handle.
+
+    Example:
+      # read a file's lines by consuming the iterator with a list
+      with open("filename", "r") as fp: lines = list(fp)
+    """
+    return self._fp.next()
+
+  @_error_wrapper
+  @_synchronized
+  def Size(self):   # pylint: disable=invalid-name
+    """Get byte size of the file from the underlying file handle."""
+    cur = self.tell()
+    try:
+      self.seek(0, 2)
+      size = self.tell()
+    finally:
+      self.seek(cur)
+    return size
+
+  @_error_wrapper
+  @_synchronized
+  def read(self, n=-1):
+    """Read n bytes from the underlying file handle.
+
+    Args:
+      n: Number of bytes to read (if negative, read to end of file handle.)
+
+    Returns:
+      A string of the bytes read, up to the end of file.
+    """
+    return self._fp.read(n)
+
+  @_error_wrapper
+  @_synchronized
+  def close(self):
+    """Close the underlying file handle."""
+    self._fp.close()
+
+  # Declare wrappers as staticmethods at the end so that we can
+  # use them as decorators.
+  _error_wrapper = staticmethod(_error_wrapper)
+  _synchronized = staticmethod(_synchronized)
+
+
+class GFile(_GFileBase):
+  """File I/O wrappers with thread locking."""
+
+  def __init__(self, name, mode='r'):
+    super(GFile, self).__init__(name, mode, _Pythonlocker())
+
+
+class FastGFile(_GFileBase):
+  """File I/O wrappers without thread locking."""
+
+  def __init__(self, name, mode='r'):
+    super(FastGFile, self).__init__(name, mode, _Nulllocker())
+
+
+# locker classes.  Note that locks must be reentrant, so that multiple
+# lock() calls by the owning thread will not block.
+class _Pythonlocker(object):
+  """A locking strategy that uses standard locks from the thread module."""
+
+  def __init__(self):
+    self._lock = threading.RLock()
+
+  def lock(self):
+    self._lock.acquire()
+
+  def unlock(self):
+    self._lock.release()
+
+
+class _Nulllocker(object):
+  """A locking strategy where lock() and unlock() methods are no-ops."""
+
+  def lock(self):
+    pass
+
+  def unlock(self):
+    pass
+
+
+def _func_error_wrapper(fn):
+  """Decorator wrapping function errors."""
+  @functools.wraps(fn)  # Preserve methods' __doc__
+  def wrap(*args, **kwargs):
+    try:
+      return fn(*args, **kwargs)
+    except ValueError, e:
+      raise FileError(errno.EIO, e.message)
+    except IOError, e:
+      raise FileError(e)
+    except OSError, e:
+      raise GOSError(e)
+  return wrap
+
+
+@_func_error_wrapper
+def Exists(path):   # pylint: disable=invalid-name
+  """Retruns True iff "path" exists (as a dir, file, non-broken symlink)."""
+  return os.path.exists(path)
+
+
+@_func_error_wrapper
+def IsDirectory(path):   # pylint: disable=invalid-name
+  """Return True iff "path" exists and is a directory."""
+  return os.path.isdir(path)
+
+
+@_func_error_wrapper
+def Glob(glob):   # pylint: disable=invalid-name
+  """Return a list of filenames matching the glob "glob"."""
+  return _glob.glob(glob)
+
+
+@_func_error_wrapper
+def MkDir(path, mode=0755):   # pylint: disable=invalid-name
+  """Create the directory "path" with the given mode.
+
+  Args:
+    path: The directory path
+    mode: The file mode for the directory
+
+  Returns:
+    None
+
+  Raises:
+    GOSError: if the path already exists
+  """
+  os.mkdir(path, mode)
+
+
+@_func_error_wrapper
+def MakeDirs(path, mode=0755):   # pylint: disable=invalid-name
+  """Recursively create the directory "path" with the given mode.
+
+  Args:
+    path: The directory path
+    mode: The file mode for the created directories
+
+  Returns:
+    None
+
+
+  Raises:
+    GOSError: if the path already exists
+  """
+  os.makedirs(path, mode)
+
+
+@_func_error_wrapper
+def RmDir(directory):   # pylint: disable=invalid-name
+  """Removes the directory "directory" iff the directory is empty.
+
+  Args:
+    directory: The directory to remove.
+
+  Raises:
+    GOSError: If the directory does not exist or is not empty.
+  """
+  os.rmdir(directory)
+
+
+@_func_error_wrapper
+def Remove(path):   # pylint: disable=invalid-name
+  """Delete the (non-directory) file "path".
+
+  Args:
+    path: The file to remove.
+
+  Raises:
+    GOSError: If "path" does not exist, is a directory, or cannot be deleted.
+  """
+  os.remove(path)
+
+
+@_func_error_wrapper
+def DeleteRecursively(path):   # pylint: disable=invalid-name
+  """Delete the file or directory "path" recursively.
+
+  Args:
+    path: The path to remove (may be a non-empty directory).
+
+  Raises:
+    GOSError: If the path does not exist or cannot be deleted.
+  """
+  if IsDirectory(path):
+    shutil.rmtree(path)
+  else:
+    Remove(path)
+
+
+@_func_error_wrapper
+def ListDirectory(directory, return_dotfiles=False):  # pylint: disable=invalid-name
+  """Returns a list of files in dir.
+
+  As with the standard os.listdir(), the filenames in the returned list will be
+  the basenames of the files in dir (not absolute paths).  To get a list of
+  absolute paths of files in a directory, a client could do:
+    file_list = gfile.ListDir(my_dir)
+    file_list = [os.path.join(my_dir, f) for f in file_list]
+  (assuming that my_dir itself specified an absolute path to a directory).
+
+  Args:
+    directory: the directory to list
+    return_dotfiles: if True, dotfiles will be returned as well.  Even if
+      this arg is True, '.' and '..' will not be returned.
+
+  Returns:
+    ['list', 'of', 'files']. The entries '.' and '..' are never returned.
+    Other entries starting with a dot will only be returned if return_dotfiles
+    is True.
+  Raises:
+    GOSError: if there is an error retrieving the directory listing.
+  """
+  files = os.listdir(directory)
+  if not return_dotfiles:
+    files = [f for f in files if not f.startswith('.')]
+  return files