# Copyright (C) 2005-2014 Bastian Kleineidam
#
# This program 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 2 of the License, or
# (at your option) any later version.
#
# This program 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 this program; if not, write to the Free Software Foundation, Inc.,
# 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
"""
File and path utilities.
"""
import os
import locale
import stat
import tempfile
import importlib
from functools import lru_cache
[docs]
def has_module(name, without_error=True):
"""Test if given module can be imported.
@param without_error: True if module must not throw any errors when importing
@return: flag if import is successful
@rtype: bool
"""
try:
importlib.import_module(name)
return True
except ImportError:
return False
except Exception:
# some modules raise errors when intitializing
return not without_error
[docs]
def get_mtime(filename):
"""Return modification time of filename or zero on errors."""
try:
return os.path.getmtime(filename)
except os.error:
return 0
[docs]
def get_size(filename):
"""Return file size in Bytes, or -1 on error."""
try:
return os.path.getsize(filename)
except os.error:
return -1
# http://developer.gnome.org/doc/API/2.0/glib/glib-running.html
if "G_FILENAME_ENCODING" in os.environ:
FSCODING = os.environ["G_FILENAME_ENCODING"].split(",")[0]
if FSCODING == "@locale":
FSCODING = locale.getpreferredencoding()
elif "G_BROKEN_FILENAMES" in os.environ:
FSCODING = locale.getpreferredencoding()
else:
FSCODING = "utf-8"
[docs]
def path_safe(path):
"""Ensure path string is compatible with the platform file system encoding."""
if path and not os.path.supports_unicode_filenames:
path = path.encode(FSCODING, "replace").decode(FSCODING)
return path
[docs]
def get_temp_file(mode='r', **kwargs):
"""Return tuple (open file object, filename) pointing to a temporary
file."""
fd, filename = tempfile.mkstemp(**kwargs)
return os.fdopen(fd, mode), filename
[docs]
def is_tty(fp):
"""Check if is a file object pointing to a TTY."""
return hasattr(fp, "isatty") and fp.isatty()
[docs]
@lru_cache(128)
def is_readable(filename):
"""Check if file is readable."""
return os.access(filename, os.R_OK)
[docs]
def is_accessable_by_others(filename):
"""Check if file is group or world accessible."""
mode = os.stat(filename)[stat.ST_MODE]
return mode & (stat.S_IRWXG | stat.S_IRWXO)
[docs]
def is_writable_by_others(filename):
"""Check if file or directory is world writable."""
mode = os.stat(filename)[stat.ST_MODE]
return mode & stat.S_IWOTH
[docs]
def is_valid_config_source(filename):
"""Check if the file is a valid config file."""
return os.path.exists(filename) and (
os.path.isfile(filename) or stat.S_ISFIFO(os.stat(filename).st_mode))