Lib/os2emxpath.py

   1 # Module 'os2emxpath' -- common operations on OS/2 pathnames
   2 """Common pathname manipulations, OS/2 EMX version.
   3
   4 Instead of importing this module directly, import os and refer to this
   5 module as os.path.
   6 """
   7
   8 import os
   9 import stat
  10 from genericpath import *
  11 from ntpath import (expanduser, expandvars, isabs, islink, splitdrive,
  12                     splitext, split, walk)
  13
  14 __all__ = ["normcase","isabs","join","splitdrive","split","splitext",
  15            "basename","dirname","commonprefix","getsize","getmtime",
  16            "getatime","getctime", "islink","exists","lexists","isdir","isfile",
  17            "ismount","walk","expanduser","expandvars","normpath","abspath",
  18            "splitunc","curdir","pardir","sep","pathsep","defpath","altsep",
  19            "extsep","devnull","realpath","supports_unicode_filenames"]
  20
  21 # strings representing various path-related bits and pieces
  22 curdir = '.'
  23 pardir = '..'
  24 extsep = '.'
  25 sep = '/'
  26 altsep = '\\'
  27 pathsep = ';'
  28 defpath = '.;C:\\bin'
  29 devnull = 'nul'
  30
  31 # Normalize the case of a pathname and map slashes to backslashes.
  32 # Other normalizations (such as optimizing '../' away) are not done
  33 # (this is done by normpath).
  34
  35 def normcase(s):
  36     """Normalize case of pathname.
  37
  38     Makes all characters lowercase and all altseps into seps."""
  39     return s.replace('\\', '/').lower()
  40
  41
  42 # Join two (or more) paths.
  43
  44 def join(a, *p):
  45     """Join two or more pathname components, inserting sep as needed"""
  46     path = a
  47     for b in p:
  48         if isabs(b):
  49             path = b
  50         elif path == '' or path[-1:] in '/\\:':
  51             path = path + b
  52         else:
  53             path = path + '/' + b
  54     return path
  55
  56
  57 # Parse UNC paths
  58 def splitunc(p):
  59     """Split a pathname into UNC mount point and relative path specifiers.
  60
  61     Return a 2-tuple (unc, rest); either part may be empty.
  62     If unc is not empty, it has the form '//host/mount' (or similar
  63     using backslashes).  unc+rest is always the input path.
  64     Paths containing drive letters never have an UNC part.
  65     """
  66     if p[1:2] == ':':
  67         return '', p # Drive letter present
  68     firstTwo = p[0:2]
  69     if firstTwo == '/' * 2 or firstTwo == '\\' * 2:
  70         # is a UNC path:
  71         # vvvvvvvvvvvvvvvvvvvv equivalent to drive letter
  72         # \\machine\mountpoint\directories...
  73         #           directory ^^^^^^^^^^^^^^^
  74         normp = normcase(p)
  75         index = normp.find('/', 2)
  76         if index == -1:
  77             ##raise RuntimeError, 'illegal UNC path: "' + p + '"'
  78             return ("", p)
  79         index = normp.find('/', index + 1)
  80         if index == -1:
  81             index = len(p)
  82         return p[:index], p[index:]
  83     return '', p
  84
  85
  86 # Return the tail (basename) part of a path.
  87
  88 def basename(p):
  89     """Returns the final component of a pathname"""
  90     return split(p)[1]
  91
  92
  93 # Return the head (dirname) part of a path.
  94
  95 def dirname(p):
  96     """Returns the directory component of a pathname"""
  97     return split(p)[0]
  98
  99
 100 # alias exists to lexists
 101 lexists = exists
 102
 103
 104 # Is a path a directory?
 105
 106 # Is a path a mount point?  Either a root (with or without drive letter)
 107 # or an UNC path with at most a / or \ after the mount point.
 108
 109 def ismount(path):
 110     """Test whether a path is a mount point (defined as root of drive)"""
 111     unc, rest = splitunc(path)
 112     if unc:
 113         return rest in ("", "/", "\\")
 114     p = splitdrive(path)[1]
 115     return len(p) == 1 and p[0] in '/\\'
 116
 117
 118 # Normalize a path, e.g. A//B, A/./B and A/foo/../B all become A/B.
 119
 120 def normpath(path):
 121     """Normalize path, eliminating double slashes, etc."""
 122     path = path.replace('\\', '/')
 123     prefix, path = splitdrive(path)
 124     while path[:1] == '/':
 125         prefix = prefix + '/'
 126         path = path[1:]
 127     comps = path.split('/')
 128     i = 0
 129     while i < len(comps):
 130         if comps[i] == '.':
 131             del comps[i]
 132         elif comps[i] == '..' and i > 0 and comps[i-1] not in ('', '..'):
 133             del comps[i-1:i+1]
 134             i = i - 1
 135         elif comps[i] == '' and i > 0 and comps[i-1] != '':
 136             del comps[i]
 137         else:
 138             i = i + 1
 139     # If the path is now empty, substitute '.'
 140     if not prefix and not comps:
 141         comps.append('.')
 142     return prefix + '/'.join(comps)
 143
 144
 145 # Return an absolute path.
 146 def abspath(path):
 147     """Return the absolute version of a path"""
 148     if not isabs(path):
 149         path = join(os.getcwd(), path)
 150     return normpath(path)
 151
 152 # realpath is a no-op on systems without islink support
 153 realpath = abspath
 154
 155 supports_unicode_filenames = False