Lib/macurl2path.py

   1 """Macintosh-specific module for conversion between pathnames and URLs.
   2
   3 Do not import directly; use urllib instead."""
   4
   5 import urllib
   6 import os
   7
   8 __all__ = ["url2pathname","pathname2url"]
   9
  10 def url2pathname(pathname):
  11     "Convert /-delimited pathname to mac pathname"
  12     #
  13     # XXXX The .. handling should be fixed...
  14     #
  15     tp = urllib.splittype(pathname)[0]
  16     if tp and tp != 'file':
  17         raise RuntimeError, 'Cannot convert non-local URL to pathname'
  18     # Turn starting /// into /, an empty hostname means current host
  19     if pathname[:3] == '///':
  20         pathname = pathname[2:]
  21     elif pathname[:2] == '//':
  22         raise RuntimeError, 'Cannot convert non-local URL to pathname'
  23     components = pathname.split('/')
  24     # Remove . and embedded ..
  25     i = 0
  26     while i < len(components):
  27         if components[i] == '.':
  28             del components[i]
  29         elif components[i] == '..' and i > 0 and \
  30                                   components[i-1] not in ('', '..'):
  31             del components[i-1:i+1]
  32             i = i-1
  33         elif components[i] == '' and i > 0 and components[i-1] != '':
  34             del components[i]
  35         else:
  36             i = i+1
  37     if not components[0]:
  38         # Absolute unix path, don't start with colon
  39         rv = ':'.join(components[1:])
  40     else:
  41         # relative unix path, start with colon. First replace
  42         # leading .. by empty strings (giving ::file)
  43         i = 0
  44         while i < len(components) and components[i] == '..':
  45             components[i] = ''
  46             i = i + 1
  47         rv = ':' + ':'.join(components)
  48     # and finally unquote slashes and other funny characters
  49     return urllib.unquote(rv)
  50
  51 def pathname2url(pathname):
  52     "convert mac pathname to /-delimited pathname"
  53     if '/' in pathname:
  54         raise RuntimeError, "Cannot convert pathname containing slashes"
  55     components = pathname.split(':')
  56     # Remove empty first and/or last component
  57     if components[0] == '':
  58         del components[0]
  59     if components[-1] == '':
  60         del components[-1]
  61     # Replace empty string ('::') by .. (will result in '/../' later)
  62     for i in range(len(components)):
  63         if components[i] == '':
  64             components[i] = '..'
  65     # Truncate names longer than 31 bytes
  66     components = map(_pncomp2url, components)
  67
  68     if os.path.isabs(pathname):
  69         return '/' + '/'.join(components)
  70     else:
  71         return '/'.join(components)
  72
  73 def _pncomp2url(component):
  74     component = urllib.quote(component[:31], safe='')  # We want to quote slashes
  75     return component
  76
  77 def test():
  78     for url in ["index.html",
  79                 "bar/index.html",
  80                 "/foo/bar/index.html",
  81                 "/foo/bar/",
  82                 "/"]:
  83         print `url`, '->', `url2pathname(url)`
  84     for path in ["drive:",
  85                  "drive:dir:",
  86                  "drive:dir:file",
  87                  "drive:file",
  88                  "file",
  89                  ":file",
  90                  ":dir:",
  91                  ":dir:file"]:
  92         print `path`, '->', `pathname2url(path)`
  93
  94 if __name__ == '__main__':
  95     test()