#----------------------------------------------------------------------
# Name: relpath.py
# Purpose:
#
# Author: Riaan Booysen
#
# Created: 1999
# RCS-ID: $Id: relpath.py,v 1.9 2006/10/09 15:14:32 riaan Exp $
# Copyright: (c) 1999 - 2003 Riaan Booysen
# Licence: GPL
#----------------------------------------------------------------------
##b = 'c:\\a\\b\\f\\d'
##d = 'c:\\a\\b\\f\\h.txt'
##d = 'c:\\a\\b\\h\\i\\j.txt'
##e = 'd:\\z\\x\\y\\j\\k.txt'
import os
def splitpath(apath):
""" Splits a path into a list of directory names """
path_list = []
drive, apath = os.path.splitdrive(apath)
head, tail = os.path.split(apath)
while 1:
if tail:
path_list.insert(0, tail)
newhead, tail = os.path.split(head)
if newhead == head:
break
else:
head = newhead
if drive:
path_list.insert(0, drive)
return path_list
def relpath(base, comp):
""" Return a path to file comp relative to path base. """
protsplitbase = base.split('://')
if len(protsplitbase) == 1:
baseprot, nbase = 'file', protsplitbase[0]
elif len(protsplitbase) == 2:
baseprot, nbase = protsplitbase
elif len(protsplitbase) == 3:
baseprot, nbase, zipentry = protsplitbase
else:
raise Exception, 'Unhandled path %s'%`protsplitbase`
protsplitcomp = comp.split('://')
if len(protsplitcomp) == 1:
compprot, ncomp = 'file', protsplitcomp[0]
elif len(protsplitcomp) == 2:
compprot, ncomp = protsplitcomp
elif len(protsplitcomp) == 3:
compprot, ncomp, zipentry = protsplitcomp
else:
raise Exception, 'Unhandled path %s'%`protsplitcomp`
if baseprot != compprot:
return comp
base_drive, base_path = os.path.splitdrive(nbase)
comp_drive, comp_path = os.path.splitdrive(ncomp)
base_path_list = splitpath(base_path)
comp_path_list = splitpath(comp_path)
if base_drive != comp_drive:
return comp
# relative path defaults to the list of files with
# a greater index then the entire base
rel_path = comp_path_list[len(base_path_list):]
# find the first directory for which the 2 paths differ
found = -1
idx = 0
for idx in range(len(base_path_list)):
if base_path_list[idx].lower() != comp_path_list[idx].lower():
rel_path = comp_path_list[idx:]
found = 0
break
for cnt in range(max(len(base_path_list) - idx + found, 0)):
rel_path.insert(0, os.pardir)
return os.path.join(*rel_path)
#print relpath(b, d)
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