# util.py - utility functions and platform specfic implementations

#

# Copyright 2005 K. Thananchayan <thananck@yahoo.com>

#

# This software may be used and distributed according to the terms

# of the GNU General Public License, incorporated herein by reference.

import os

def rename(src, dst):

    try:

        os.rename(src, dst)

    except:

        os.unlink(dst)

        os.rename(src, dst)

# Platfor specific varients

if os.name == 'nt':

    nulldev = 'NUL:'

    def is_exec(f, last):

        return last

    def set_exec(f, mode):

        pass

    def pconvert(path):

        return path.replace("\\", "/")

    def makelock(info, pathname):

        ld = os.open(pathname, os.O_CREAT | os.O_WRONLY | os.O_EXCL)

        os.write(ld, info)

        os.close(ld)

    def readlock(pathname):

        return file(pathname).read()

else:

    nulldev = '/dev/null'

    def is_exec(f, last):

        return (os.stat(f).st_mode & 0100 != 0)

    def set_exec(f, mode):

        s = os.stat(f).st_mode

        if (s & 0100 != 0) == mode:

            return

        if mode:

            # Turn on +x for every +r bit when making a file executable

            # and obey umask.

            umask = os.umask(0)

            os.umask(umask)

            os.chmod(f, s | (s & 0444) >> 2 & ~umask)

        else:

            os.chmod(f, s & 0666)

    def pconvert(path):

        return path

    def makelock(info, pathname):

        os.symlink(info, pathname)

    def readlock(pathname):

        return os.readlink(pathname)