PC World Komputer 2010 April/PCWorld0410.iso/hity wydania/Ubuntu 9.10 PL/karmelkowy-koliberek-desktop-9.10-i386-PL.iso/casper/filesystem.squashfs/usr/lib/python2.6/tempfile.pyc

Python Compiled Bytecode | 2009-11-11 | 19KB | 638 lines

# Source Generated with Decompyle++
# File: in.pyc (Python 2.6)

'''Temporary files.

This module provides generic, low- and high-level interfaces for
creating temporary files and directories.  The interfaces listed
as "safe" just below can be used without fear of race conditions.
Those listed as "unsafe" cannot, and are provided for backward
compatibility only.

This module also provides some data items to the user:

  TMP_MAX  - maximum number of names that will be tried before
             giving up.
  template - the default prefix for all temporary names.
             You may change this to control the default prefix.
  tempdir  - If this is set to a string before the first use of
             any routine from this module, it will be considered as
             another candidate location to store temporary files.
'''
__all__ = [
    'NamedTemporaryFile',
    'TemporaryFile',
    'SpooledTemporaryFile',
    'mkstemp',
    'mkdtemp',
    'mktemp',
    'TMP_MAX',
    'gettempprefix',
    'tempdir',
    'gettempdir']
import os as _os
import errno as _errno
from random import Random as _Random

try:
    from cStringIO import StringIO as _StringIO
except ImportError:
    from StringIO import StringIO as _StringIO


try:
    import fcntl as _fcntl
except ImportError:

    def _set_cloexec(fd):
        pass



def _set_cloexec(fd):

    try:
        flags = _fcntl.fcntl(fd, _fcntl.F_GETFD, 0)
    except IOError:
        pass

    flags |= _fcntl.FD_CLOEXEC
    _fcntl.fcntl(fd, _fcntl.F_SETFD, flags)


try:
    import thread as _thread
except ImportError:
    import dummy_thread as _thread

_allocate_lock = _thread.allocate_lock
_text_openflags = _os.O_RDWR | _os.O_CREAT | _os.O_EXCL
if hasattr(_os, 'O_NOINHERIT'):
    _text_openflags |= _os.O_NOINHERIT

if hasattr(_os, 'O_NOFOLLOW'):
    _text_openflags |= _os.O_NOFOLLOW

_bin_openflags = _text_openflags
if hasattr(_os, 'O_BINARY'):
    _bin_openflags |= _os.O_BINARY

if hasattr(_os, 'TMP_MAX'):
    TMP_MAX = _os.TMP_MAX
else:
    TMP_MAX = 10000
template = 'tmp'
_once_lock = _allocate_lock()
if hasattr(_os, 'lstat'):
    _stat = _os.lstat
elif hasattr(_os, 'stat'):
    _stat = _os.stat
else:

    def _stat(fn):

        try:
            f = open(fn)
        except IOError:
            raise _os.error

        f.close()


def _exists(fn):

    try:
        _stat(fn)
    except _os.error:
        return False

    return True


class _RandomNameSequence:
    '''An instance of _RandomNameSequence generates an endless
    sequence of unpredictable strings which can safely be incorporated
    into file names.  Each string is six characters long.  Multiple
    threads can safely use the same instance at the same time.

    _RandomNameSequence is an iterator.'''
    characters = 'abcdefghijklmnopqrstuvwxyz' + 'ABCDEFGHIJKLMNOPQRSTUVWXYZ' + '0123456789_'

    def __init__(self):
        self.mutex = _allocate_lock()
        self.rng = _Random()
        self.normcase = _os.path.normcase


    def __iter__(self):
        return self


    def next(self):
        m = self.mutex
        c = self.characters
        choose = self.rng.choice
        m.acquire()

        try:
            letters = [ choose(c) for dummy in '123456' ]
        finally:
            m.release()

        return self.normcase(''.join(letters))



def _candidate_tempdir_list():
    '''Generate a list of candidate temporary directories which
    _get_default_tempdir will try.'''
    dirlist = []
    for envname in ('TMPDIR', 'TEMP', 'TMP'):
        dirname = _os.getenv(envname)
        if dirname:
            dirlist.append(dirname)
            continue

    if _os.name == 'riscos':
        dirname = _os.getenv('Wimp$ScrapDir')
        if dirname:
            dirlist.append(dirname)

    elif _os.name == 'nt':
        dirlist.extend([
            'c:\\temp',
            'c:\\tmp',
            '\\temp',
            '\\tmp'])
    else:
        dirlist.extend([
            '/tmp',
            '/var/tmp',
            '/usr/tmp'])

    try:
        dirlist.append(_os.getcwd())
    except (AttributeError, _os.error):
        dirlist.append(_os.curdir)

    return dirlist


def _get_default_tempdir():
    '''Calculate the default directory to use for temporary files.
    This routine should be called exactly once.

    We determine whether or not a candidate temp dir is usable by
    trying to create and write to a file in that directory.  If this
    is successful, the test file is deleted.  To prevent denial of
    service, the name of the test file must be randomized.'''
    namer = _RandomNameSequence()
    dirlist = _candidate_tempdir_list()
    flags = _text_openflags
    for dir in dirlist:
        if dir != _os.curdir:
            dir = _os.path.normcase(_os.path.abspath(dir))

        for seq in xrange(100):
            name = namer.next()
            filename = _os.path.join(dir, name)

            try:
                fd = _os.open(filename, flags, 384)
                fp = _os.fdopen(fd, 'w')
                fp.write('blat')
                fp.close()
                _os.unlink(filename)
                del fp
                del fd
                return dir
            continue
            except (OSError, IOError):
                e = None
                if e[0] != _errno.EEXIST:
                    break

                e[0] != _errno.EEXIST




    raise IOError, (_errno.ENOENT, 'No usable temporary directory found in %s' % dirlist)

_name_sequence = None

def _get_candidate_names():
    '''Common setup sequence for all user-callable interfaces.'''
    global _name_sequence
    if _name_sequence is None:
        _once_lock.acquire()

        try:
            if _name_sequence is None:
                _name_sequence = _RandomNameSequence()
        finally:
            _once_lock.release()


    return _name_sequence


def _mkstemp_inner(dir, pre, suf, flags):
    '''Code common to mkstemp, TemporaryFile, and NamedTemporaryFile.'''
    names = _get_candidate_names()
    for seq in xrange(TMP_MAX):
        name = names.next()
        file = _os.path.join(dir, pre + name + suf)

        try:
            fd = _os.open(file, flags, 384)
            _set_cloexec(fd)
            return (fd, _os.path.abspath(file))
        continue
        except OSError:
            e = None
            if e.errno == _errno.EEXIST:
                continue

            raise
            continue



    raise IOError, (_errno.EEXIST, 'No usable temporary file name found')


def gettempprefix():
    '''Accessor for tempdir.template.'''
    return template

tempdir = None

def gettempdir():
    '''Accessor for tempfile.tempdir.'''
    global tempdir
    if tempdir is None:
        _once_lock.acquire()

        try:
            if tempdir is None:
                tempdir = _get_default_tempdir()
        finally:
            _once_lock.release()


    return tempdir


def mkstemp(suffix = '', prefix = template, dir = None, text = False):
    """User-callable function to create and return a unique temporary
    file.  The return value is a pair (fd, name) where fd is the
    file descriptor returned by os.open, and name is the filename.

    If 'suffix' is specified, the file name will end with that suffix,
    otherwise there will be no suffix.

    If 'prefix' is specified, the file name will begin with that prefix,
    otherwise a default prefix is used.

    If 'dir' is specified, the file will be created in that directory,
    otherwise a default directory is used.

    If 'text' is specified and true, the file is opened in text
    mode.  Else (the default) the file is opened in binary mode.  On
    some operating systems, this makes no difference.

    The file is readable and writable only by the creating user ID.
    If the operating system uses permission bits to indicate whether a
    file is executable, the file is executable by no one. The file
    descriptor is not inherited by children of this process.

    Caller is responsible for deleting the file when done with it.
    """
    if dir is None:
        dir = gettempdir()

    if text:
        flags = _text_openflags
    else:
        flags = _bin_openflags
    return _mkstemp_inner(dir, prefix, suffix, flags)


def mkdtemp(suffix = '', prefix = template, dir = None):
    """User-callable function to create and return a unique temporary
    directory.  The return value is the pathname of the directory.

    Arguments are as for mkstemp, except that the 'text' argument is
    not accepted.

    The directory is readable, writable, and searchable only by the
    creating user.

    Caller is responsible for deleting the directory when done with it.
    """
    if dir is None:
        dir = gettempdir()

    names = _get_candidate_names()
    for seq in xrange(TMP_MAX):
        name = names.next()
        file = _os.path.join(dir, prefix + name + suffix)

        try:
            _os.mkdir(file, 448)
            return file
        continue
        except OSError:
            e = None
            if e.errno == _errno.EEXIST:
                continue

            raise
            continue



    raise IOError, (_errno.EEXIST, 'No usable temporary directory name found')


def mktemp(suffix = '', prefix = template, dir = None):
    """User-callable function to return a unique temporary file name.  The
    file is not created.

    Arguments are as for mkstemp, except that the 'text' argument is
    not accepted.

    This function is unsafe and should not be used.  The file name
    refers to a file that did not exist at some point, but by the time
    you get around to creating it, someone else may have beaten you to
    the punch.
    """
    if dir is None:
        dir = gettempdir()

    names = _get_candidate_names()
    for seq in xrange(TMP_MAX):
        name = names.next()
        file = _os.path.join(dir, prefix + name + suffix)
        if not _exists(file):
            return file

    raise IOError, (_errno.EEXIST, 'No usable temporary filename found')


class _TemporaryFileWrapper:
    '''Temporary file wrapper

    This class provides a wrapper around files opened for
    temporary use.  In particular, it seeks to automatically
    remove the file when it is no longer needed.
    '''

    def __init__(self, file, name, delete = True):
        self.file = file
        self.name = name
        self.close_called = False
        self.delete = delete


    def __getattr__(self, name):
        file = self.__dict__['file']
        a = getattr(file, name)
        if not issubclass(type(a), type(0)):
            setattr(self, name, a)

        return a


    def __enter__(self):
        self.file.__enter__()
        return self

    if _os.name != 'nt':
        unlink = _os.unlink

        def close(self):
            if not self.close_called:
                self.close_called = True
                self.file.close()
                if self.delete:
                    self.unlink(self.name)




        def __del__(self):
            self.close()


        def __exit__(self, exc, value, tb):
            result = self.file.__exit__(exc, value, tb)
            self.close()
            return result




def NamedTemporaryFile(mode = 'w+b', bufsize = -1, suffix = '', prefix = template, dir = None, delete = True):
    '''Create and return a temporary file.
    Arguments:
    \'prefix\', \'suffix\', \'dir\' -- as for mkstemp.
    \'mode\' -- the mode argument to os.fdopen (default "w+b").
    \'bufsize\' -- the buffer size argument to os.fdopen (default -1).
    \'delete\' -- whether the file is deleted on close (default True).
    The file is created as mkstemp() would do it.

    Returns an object with a file-like interface; the name of the file
    is accessible as file.name.  The file will be automatically deleted
    when it is closed unless the \'delete\' argument is set to False.
    '''
    if dir is None:
        dir = gettempdir()

    if 'b' in mode:
        flags = _bin_openflags
    else:
        flags = _text_openflags
    if _os.name == 'nt' and delete:
        flags |= _os.O_TEMPORARY

    (fd, name) = _mkstemp_inner(dir, prefix, suffix, flags)
    file = _os.fdopen(fd, mode, bufsize)
    return _TemporaryFileWrapper(file, name, delete)

if _os.name != 'posix' or _os.sys.platform == 'cygwin':
    TemporaryFile = NamedTemporaryFile
else:

    def TemporaryFile(mode = 'w+b', bufsize = -1, suffix = '', prefix = template, dir = None):
        '''Create and return a temporary file.
        Arguments:
        \'prefix\', \'suffix\', \'dir\' -- as for mkstemp.
        \'mode\' -- the mode argument to os.fdopen (default "w+b").
        \'bufsize\' -- the buffer size argument to os.fdopen (default -1).
        The file is created as mkstemp() would do it.

        Returns an object with a file-like interface.  The file has no
        name, and will cease to exist when it is closed.
        '''
        if dir is None:
            dir = gettempdir()

        if 'b' in mode:
            flags = _bin_openflags
        else:
            flags = _text_openflags
        (fd, name) = _mkstemp_inner(dir, prefix, suffix, flags)

        try:
            _os.unlink(name)
            return _os.fdopen(fd, mode, bufsize)
        except:
            _os.close(fd)
            raise



class SpooledTemporaryFile:
    '''Temporary file wrapper, specialized to switch from
    StringIO to a real file when it exceeds a certain size or
    when a fileno is needed.
    '''
    _rolled = False

    def __init__(self, max_size = 0, mode = 'w+b', bufsize = -1, suffix = '', prefix = template, dir = None):
        self._file = _StringIO()
        self._max_size = max_size
        self._rolled = False
        self._TemporaryFileArgs = (mode, bufsize, suffix, prefix, dir)


    def _check(self, file):
        if self._rolled:
            return None
        max_size = self._max_size
        if max_size and file.tell() > max_size:
            self.rollover()



    def rollover(self):
        if self._rolled:
            return None
        file = self._file
        del self._TemporaryFileArgs
        newfile.write(file.getvalue())
        newfile.seek(file.tell(), 0)
        self._rolled = True


    def __enter__(self):
        if self._file.closed:
            raise ValueError('Cannot enter context with closed file')
        self._file.closed
        return self


    def __exit__(self, exc, value, tb):
        self._file.close()


    def __iter__(self):
        return self._file.__iter__()


    def close(self):
        self._file.close()


    def closed(self):
        return self._file.closed

    closed = property(closed)

    def encoding(self):
        return self._file.encoding

    encoding = property(encoding)

    def fileno(self):
        self.rollover()
        return self._file.fileno()


    def flush(self):
        self._file.flush()


    def isatty(self):
        return self._file.isatty()


    def mode(self):
        return self._file.mode

    mode = property(mode)

    def name(self):
        return self._file.name

    name = property(name)

    def newlines(self):
        return self._file.newlines

    newlines = property(newlines)

    def next(self):
        return self._file.next


    def read(self, *args):
        return self._file.read(*args)


    def readline(self, *args):
        return self._file.readline(*args)


    def readlines(self, *args):
        return self._file.readlines(*args)


    def seek(self, *args):
        self._file.seek(*args)


    def softspace(self):
        return self._file.softspace

    softspace = property(softspace)

    def tell(self):
        return self._file.tell()


    def truncate(self):
        self._file.truncate()


    def write(self, s):
        file = self._file
        rv = file.write(s)
        self._check(file)
        return rv


    def writelines(self, iterable):
        file = self._file
        rv = file.writelines(iterable)
        self._check(file)
        return rv


    def xreadlines(self, *args):
        return self._file.xreadlines(*args)