Python os.umask() Examples

def drop_privileges():
    from certidude import config
    import pwd
    _, _, uid, gid, gecos, root, shell = pwd.getpwnam("certidude")
    restricted_groups = []
    restricted_groups.append(gid)

    # PAM needs access to /etc/shadow
    if config.AUTHENTICATION_BACKENDS == {"pam"}:
        import grp
        name, passwd, num, mem = grp.getgrnam("shadow")
        click.echo("Adding current user to shadow group due to PAM authentication backend")
        restricted_groups.append(num)

    os.setgroups(restricted_groups)
    os.setgid(gid)
    os.setuid(uid)
    click.echo("Switched %s (pid=%d) to user %s (uid=%d, gid=%d); member of groups %s" %
        (getproctitle(), os.getpid(), "certidude", os.getuid(), os.getgid(), ", ".join([str(j) for j in os.getgroups()])))
    os.umask(0o007) 

def __init__(self, cfg):
        old_umask = os.umask(cfg.umask)
        fdir = cfg.worker_tmp_dir
        if fdir and not os.path.isdir(fdir):
            raise RuntimeError("%s doesn't exist. Can't create workertmp." % fdir)
        fd, name = tempfile.mkstemp(prefix="wgunicorn-", dir=fdir)

        # allows the process to write to the file
        util.chown(name, cfg.uid, cfg.gid)
        os.umask(old_umask)

        # unlink the file so we don't leak tempory files
        try:
            if not IS_CYGWIN:
                util.unlink(name)
            self._tmp = os.fdopen(fd, 'w+b', 1)
        except:
            os.close(fd)
            raise

        self.spinner = 0 

def write_option(option, value):
    """
    Write an option to disk -- doesn't handle config reloading
    """
    # deny rwx to Group and World -- don't bother storing the returned old mask
    # value, since we'll never restore it in the CLI anyway
    # do this on every call to ensure that we're always consistent about it
    os.umask(0o077)

    conf = get_config_obj()

    # add the section if absent
    if CONF_SECTION_NAME not in conf:
        conf[CONF_SECTION_NAME] = {}

    conf[CONF_SECTION_NAME][option] = value
    conf.write() 

def become_daemon(our_home_dir='.', out_log=None, err_log=None, umask=0o022):
        """
        If we're not running under a POSIX system, just simulate the daemon
        mode by doing redirections and directory changing.
        """
        os.chdir(our_home_dir)
        os.umask(umask)
        sys.stdin.close()
        sys.stdout.close()
        sys.stderr.close()
        if err_log:
            sys.stderr = open(err_log, 'a', buffering)
        else:
            sys.stderr = NullDevice()
        if out_log:
            sys.stdout = open(out_log, 'a', buffering)
        else:
            sys.stdout = NullDevice() 

def _openUploadFile(self, buildId, suffix):
        (packageResultPath, packageResultFile) = self._getPath(buildId, suffix)
        if os.path.isfile(packageResultFile):
            raise ArtifactExistsError()

        # open temporary file in destination directory
        if not os.path.isdir(packageResultPath):
            if self.__dirMode is not None:
                oldMask = os.umask(~self.__dirMode & 0o777)
            try:
                os.makedirs(packageResultPath, exist_ok=True)
            finally:
                if self.__dirMode is not None:
                    os.umask(oldMask)
        return LocalArchiveUploader(
            NamedTemporaryFile(dir=packageResultPath, delete=False),
            self.__fileMode,
            packageResultFile) 

def test_execute_bit_not_copied(self):
        # Issue 6070: under posix .pyc files got their execute bit set if
        # the .py file had the execute bit set, but they aren't executable.
        oldmask = os.umask(022)
        sys.path.insert(0, os.curdir)
        try:
            fname = TESTFN + os.extsep + "py"
            f = open(fname, 'w').close()
            os.chmod(fname, (stat.S_IRUSR | stat.S_IRGRP | stat.S_IROTH |
                             stat.S_IXUSR | stat.S_IXGRP | stat.S_IXOTH))
            __import__(TESTFN)
            fn = fname + 'c'
            if not os.path.exists(fn):
                fn = fname + 'o'
                if not os.path.exists(fn):
                    self.fail("__import__ did not result in creation of "
                              "either a .pyc or .pyo file")
            s = os.stat(fn)
            self.assertEqual(stat.S_IMODE(s.st_mode),
                             stat.S_IRUSR | stat.S_IRGRP | stat.S_IROTH)
        finally:
            os.umask(oldmask)
            remove_files(TESTFN)
            unload(TESTFN)
            del sys.path[0] 

def test_permissions_after_flush(self):
        # See issue #5346

        # Make the mailbox world writable. It's unlikely that the new
        # mailbox file would have these permissions after flush(),
        # because umask usually prevents it.
        mode = os.stat(self._path).st_mode | 0o666
        os.chmod(self._path, mode)

        self._box.add(self._template % 0)
        i = self._box.add(self._template % 1)
        # Need to remove one message to make flush() create a new file
        self._box.remove(i)
        self._box.flush()

        self.assertEqual(os.stat(self._path).st_mode, mode) 

def test_file_perms(self):
        # From bug #3228, we want to verify that the mailbox file isn't executable,
        # even if the umask is set to something that would leave executable bits set.
        # We only run this test on platforms that support umask.
        try:
            old_umask = os.umask(0077)
            self._box.close()
            os.unlink(self._path)
            self._box = mailbox.mbox(self._path, create=True)
            self._box.add('')
            self._box.close()
        finally:
            os.umask(old_umask)

        st = os.stat(self._path)
        perms = st.st_mode
        self.assertFalse((perms & 0111)) # Execute bits should all be off. 

def test_dumbdbm_creation_mode(self):
        try:
            old_umask = os.umask(0002)
            f = dumbdbm.open(_fname, 'c', 0637)
            f.close()
        finally:
            os.umask(old_umask)

        expected_mode = 0635
        if os.name != 'posix' or sys.platform == 'cli':
            # Windows and IronPython only support setting the read-only attribute.
            # This shouldn't fail, but doesn't work like Unix either.
            expected_mode = 0666

        import stat
        st = os.stat(_fname + '.dat')
        self.assertEqual(stat.S_IMODE(st.st_mode), expected_mode)
        st = os.stat(_fname + '.dir')
        self.assertEqual(stat.S_IMODE(st.st_mode), expected_mode) 

def chmod_plus_x(file):
    import os
    import stat
    umask = os.umask(0)
    os.umask(umask)
    st = os.stat(file)
    os.chmod(file, st.st_mode | ((stat.S_IXUSR | stat.S_IXGRP | stat.S_IXOTH) & ~umask)) 

def __init__(self, bus, umask=None, uid=None, gid=None):
        SimplePlugin.__init__(self, bus)
        self.finalized = False
        self.uid = uid
        self.gid = gid
        self.umask = umask 

def umask(self):
        """The default permission mode for newly created files and directories.

        Usually expressed in octal format, for example, ``0644``.
        Availability: Unix, Windows.
        """
        return self._umask 

def umask(self, val):
        if val is not None:
            try:
                os.umask
            except AttributeError:
                self.bus.log('umask function not available; ignoring umask.',
                             level=30)
                val = None
        self._umask = val 

def temp_umask(umask):
        """Context manager that temporarily sets the process umask."""
        oldmask = os.umask(umask)
        try:
            yield
        finally:
            os.umask(oldmask) 

def temp_umask(umask):
        """Context manager that temporarily sets the process umask."""
        oldmask = os.umask(umask)
        try:
            yield
        finally:
            os.umask(oldmask) 

def _daemonize(self):
        try:
            pid = os.fork()  # 第一次fork，生成子进程，脱离父进程
            if pid > 0:
                sys.exit(0)  # 退出主进程
        except OSError as e:
            sys.stderr.write('fork #1 failed: %d (%s)\n' % (e.errno, e.strerror))
            sys.exit(1)

        if self.cd:
            os.chdir("/")  # 修改工作目录
        os.setsid()  # 设置新的会话连接
        os.umask(0)  # 重新设置文件创建权限

        try:
            pid = os.fork()  # 第二次fork，禁止进程打开终端
            if pid > 0:
                sys.exit(0)
        except OSError as e:
            sys.stderr.write('fork #2 failed: %d (%s)\n' % (e.errno, e.strerror))
            sys.exit(1)

        # 重定向文件描述符
        sys.stdout.flush()
        sys.stderr.flush()
        # with open(self.stdin, 'r') as si, open(self.stdout, 'a+') as so, open(self.stderr, 'ab+', 0) as se:
        si = open(self.stdin, 'r')
        so = open(self.stdout, 'a+')
        se = open(self.stderr, 'ab+', 0)
        os.dup2(si.fileno(), sys.stdin.fileno())
        os.dup2(so.fileno(), sys.stdout.fileno())
        os.dup2(se.fileno(), sys.stderr.fileno())

        # 注册退出函数，根据文件pid判断是否存在进程
        atexit.register(self.delpid)
        pid = str(os.getpid())
        with open(self.pidfile, 'w+') as f:
            f.write('%s\n' % pid)
            # file(self.pidfile, 'w+').write('%s\n' % pid) 

def get_process_umask():
    result = os.umask(0o22)
    os.umask(result)
    return result 

def current_umask():
    """Get the current umask which involves having to set it temporarily."""
    mask = os.umask(0)
    os.umask(mask)
    return mask 

def unzip_file(filename, location, flatten=True):
    """
    Unzip the file (with path `filename`) to the destination `location`.  All
    files are written based on system defaults and umask (i.e. permissions are
    not preserved), except that regular file members with any execute
    permissions (user, group, or world) have "chmod +x" applied after being
    written. Note that for windows, any execute changes using os.chmod are
    no-ops per the python docs.
    """
    ensure_dir(location)
    zipfp = open(filename, 'rb')
    try:
        zip = zipfile.ZipFile(zipfp, allowZip64=True)
        leading = has_leading_dir(zip.namelist()) and flatten
        for info in zip.infolist():
            name = info.filename
            data = zip.read(name)
            fn = name
            if leading:
                fn = split_leading_dir(name)[1]
            fn = os.path.join(location, fn)
            dir = os.path.dirname(fn)
            if fn.endswith('/') or fn.endswith('\\'):
                # A directory
                ensure_dir(fn)
            else:
                ensure_dir(dir)
                fp = open(fn, 'wb')
                try:
                    fp.write(data)
                finally:
                    fp.close()
                    mode = info.external_attr >> 16
                    # if mode and regular file and any execute permissions for
                    # user/group/world?
                    if mode and stat.S_ISREG(mode) and mode & 0o111:
                        # make dest file have execute for user/group/world
                        # (chmod +x) no-op on windows per python docs
                        os.chmod(fn, (0o777 - current_umask() | 0o111))
    finally:
        zipfp.close() 

def get_process_umask():
    result = os.umask(0o22)
    os.umask(result)
    return result 

def current_umask():
    """Get the current umask which involves having to set it temporarily."""
    mask = os.umask(0)
    os.umask(mask)
    return mask 

def unzip_file(filename, location, flatten=True):
    """
    Unzip the file (with path `filename`) to the destination `location`.  All
    files are written based on system defaults and umask (i.e. permissions are
    not preserved), except that regular file members with any execute
    permissions (user, group, or world) have "chmod +x" applied after being
    written. Note that for windows, any execute changes using os.chmod are
    no-ops per the python docs.
    """
    ensure_dir(location)
    zipfp = open(filename, 'rb')
    try:
        zip = zipfile.ZipFile(zipfp, allowZip64=True)
        leading = has_leading_dir(zip.namelist()) and flatten
        for info in zip.infolist():
            name = info.filename
            data = zip.read(name)
            fn = name
            if leading:
                fn = split_leading_dir(name)[1]
            fn = os.path.join(location, fn)
            dir = os.path.dirname(fn)
            if fn.endswith('/') or fn.endswith('\\'):
                # A directory
                ensure_dir(fn)
            else:
                ensure_dir(dir)
                fp = open(fn, 'wb')
                try:
                    fp.write(data)
                finally:
                    fp.close()
                    mode = info.external_attr >> 16
                    # if mode and regular file and any execute permissions for
                    # user/group/world?
                    if mode and stat.S_ISREG(mode) and mode & 0o111:
                        # make dest file have execute for user/group/world
                        # (chmod +x) no-op on windows per python docs
                        os.chmod(fn, (0o777 - current_umask() | 0o111))
    finally:
        zipfp.close() 

def current_umask():
    tmp = os.umask(0o022)
    os.umask(tmp)
    return tmp 

def __init__(self):
        os.umask(0)
        self.storage_root = "/pnfs"
        self.scratch_dir = "/scratch/"
        self.pcache_dir = self.scratch_dir + "pcache/"
        self.log_file = self.pcache_dir + "pcache.log"
        self.max_space = "80%"
        self.percent_max = None
        self.bytes_max = None
        # self.max_space = "10T"
        self.hysterisis = 0.75
        # self.hysterisis = 0.9
        self.clean = False
        self.transfer_timeout = "600"
        self.max_retries = 3
        self.guid = None
        self.accept_patterns = []
        self.reject_patterns = []
        self.force = False
        self.flush = False
        self.verbose = False
        self.quiet = False
        self.debug = False
        self.hostname = None
        self.sitename = None  # XXX can we get this from somewhere?
        self.update_panda = False
        self.panda_url = "https://pandaserver.cern.ch:25443/server/panda/"
        self.local_src = None
        self.skip_download = False

        # internal variables
        self.sleep_interval = 15
        self.force = False
        self.locks = {}
        self.deleted_guids = []
        self.version = pcacheversion 

def daemonize(self):
        if self.debug:
            return
        try:
            os.setsid()
        except OSError:
            pass
        try:
            os.chdir("/")
        except OSError:
            pass
        try:
            os.umask(0)
        except OSError:
            pass
        n = os.open("/dev/null", os.O_RDWR)
        i, o, e = sys.stdin.fileno(), sys.stdout.fileno(), sys.stderr.fileno()
        os.dup2(n, i)
        os.dup2(n, o)
        os.dup2(n, e)
        MAXFD = 1024
        try:
            import resource  # Resource usage information.
            maxfd = resource.getrlimit(resource.RLIMIT_NOFILE)[1]
            if (maxfd == resource.RLIM_INFINITY):
                maxfd = MAXFD
        except:
            try:
                maxfd = os.sysconf("SC_OPEN_MAX")
            except:
                maxfd = MAXFD  # use default value

        for fd in range(0, maxfd + 1):
            try:
                os.close(fd)
            except:
                pass

    # Panda server callback functions 

def _create_file_if_needed(self):
    """Create an empty file if necessary.

    This method will not initialize the file. Instead it implements a
    simple version of "touch" to ensure the file has been created.
    """
    if not os.path.exists(self._filename):
      old_umask = os.umask(0177)
      try:
        open(self._filename, 'a+b').close()
      finally:
        os.umask(old_umask) 

def _create_file_if_needed(self):
    """Create an empty file if necessary.

    This method will not initialize the file. Instead it implements a
    simple version of "touch" to ensure the file has been created.
    """
    if not os.path.exists(self._file.filename()):
      old_umask = os.umask(0177)
      try:
        open(self._file.filename(), 'a+b').close()
      finally:
        os.umask(old_umask) 

def temp_umask(umask):
    oldmask = os.umask(umask)
    try:
        yield
    finally:
        os.umask(oldmask) 

def become_daemon(our_home_dir='.', out_log='/dev/null',
                      err_log='/dev/null', umask=0o022):
        "Robustly turn into a UNIX daemon, running in our_home_dir."
        # First fork
        try:
            if os.fork() > 0:
                sys.exit(0)     # kill off parent
        except OSError as e:
            sys.stderr.write("fork #1 failed: (%d) %s\n" % (e.errno, e.strerror))
            sys.exit(1)
        os.setsid()
        os.chdir(our_home_dir)
        os.umask(umask)

        # Second fork
        try:
            if os.fork() > 0:
                os._exit(0)
        except OSError as e:
            sys.stderr.write("fork #2 failed: (%d) %s\n" % (e.errno, e.strerror))
            os._exit(1)

        si = open('/dev/null', 'r')
        so = open(out_log, 'a+', buffering)
        se = open(err_log, 'a+', buffering)
        os.dup2(si.fileno(), sys.stdin.fileno())
        os.dup2(so.fileno(), sys.stdout.fileno())
        os.dup2(se.fileno(), sys.stderr.fileno())
        # Set custom file descriptors so that they get proper buffering.
        sys.stdout, sys.stderr = so, se 

def current_umask():
    """Get the current umask which involves having to set it temporarily."""
    mask = os.umask(0)
    os.umask(mask)
    return mask