text: # Copyright (C) 2010 Google Inc. All rights reserved.
  #
  # Redistribution and use in source and binary forms, with or without
  # modification, are permitted provided that the following conditions are
  # met:
  #
  #     * Redistributions of source code must retain the above copyright
  # notice, this list of conditions and the following disclaimer.
  #     * Redistributions in binary form must reproduce the above
  # copyright notice, this list of conditions and the following disclaimer
  # in the documentation and/or other materials provided with the
  # distribution.
  #     * Neither the name of Google Inc. nor the names of its
  # contributors may be used to endorse or promote products derived from
  # this software without specific prior written permission.
  #
  # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  # "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  # LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  # A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  # OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  # SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  # LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  # DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  # THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  """Generic routines to convert platform-specific paths to URIs."""
  
  import urllib
  
  
  def abspath_to_uri(platform, path):
      """Converts a platform-specific absolute path to a file: URL."""
      return 'file:' + _escape(_convert_path(platform, path))
  
  
  def _escape(path):
      """Handle any characters in the path that should be escaped."""
      # FIXME: web browsers don't appear to blindly quote every character
      # when converting filenames to files. Instead of using urllib's default
      # rules, we allow a small list of other characters through un-escaped.
      # It's unclear if this is the best possible solution.
      return urllib.quote(path, safe='/+:')
  
  
  def _convert_path(platform, path):
      """Handles any os-specific path separators, mappings, etc."""
      if platform.is_win():
          return _winpath_to_uri(path)
      return _unixypath_to_uri(path)
  
  
  def _winpath_to_uri(path):
      """Converts a window absolute path to a file: URL."""
      return '///' + path.replace('\\', '/')
  
  
  def _unixypath_to_uri(path):
      """Converts a unix-style path to a file: URL."""
      return '//' + path
  