root/cleverbox/trunk/cleverbox/utils/filesystem.py

# This file is part of the "Cleverbox" program.
#
# Cleverbox is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# Cleverbox is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with Cleverbox.  If not, see <http://www.gnu.org/licenses/>.
#
# Copyright 2008, Tristan Rivoallan

"""
This module regroups miscelaneous filesystem related functions.
"""

import pwd, grp, os, stat

def chowntree(directory, uid, gid):
    """
    Recursive chown.
    """
    try:
        if (os.path.isdir(directory)):
            os.chown(directory, uid, gid)
            direntries = os.listdir(directory)
            for direntry in direntries:
                direntry = os.path.join(directory, direntry)
                if (os.path.isdir(direntry)):
                    os.chown(direntry, uid, gid)
                    os.chdir(direntry)
                    chowntree(direntry, uid, gid)
                else:
                    os.chown(direntry, uid, gid)
        else:
            os.chown(directory, uid, gid)
    except (IOError, os.error), why:
        print "rchown %s: %s" % (str(directory), str(why))

def chmodtree(arg, dirname, fnames):
    """ To be used with os.path.walk. """

    os.chmod(dirname, arg)
    for file in fnames:
        os.chmod(os.path.join(dirname, file), arg)


def get_uid_from_name(username):
    """
    Returns uid corresponding to given username.
    """
    return pwd.getpwnam(username)[2]
        
def get_gid_from_name(groupname):
    """
    Returns gid corresponding to given groupname.
    """
    return grp.getgrnam(groupname)[2]

def is_file(path):
   """
   Returns true if path points to a regular file (stat.S_ISREG).
   """
   mode = os.stat(path)[stat.ST_MODE]
   return stat.S_ISREG(mode)

def is_directory(path):
   """
   Returns true if path points to a directory (stat.S_ISDIR).
   """
   mode = os.stat(path)[stat.ST_MODE]
   return stat.S_ISDIR(mode)

def is_symlink(path):
   """
   Returns true if path points to a symlink (stat.S_ISLNK).
   """
   mode = os.stat(path)[stat.ST_MODE]
   return stat.S_ISLNK(mode)

def set_permissions(permissions):
    for (entry, spec) in permissions.items():
        os.chmod(entry, spec[0])
        os.chown(entry,
                 get_uid_from_name(spec[1]),
                 get_gid_from_name(spec[2]))