1653 lines
56 KiB
Python
1653 lines
56 KiB
Python
"""This is based on _pyio.py from CPython 2.7 which is Python implementation of
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the io module. The upgrade from a 2.6-ish version accounts for the large
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number of changes made all at once.
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It is here to stand in for classes that should be provided by the Java
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implementation of the _io module. In CPython 2.7, when client code
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imports io, that module imports a set of classes from _io and
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re-exports them as its own. In Jython, io.py imports those things from
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_io, which in turn imports from _jyio those so far implemented in
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Java. Consequently _io implements the rest here using nearly the same
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code as _pyio. (Previous to Jython 2.7.1, the import was reversed:
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this specific Python-based module was named _jyio, and it imported
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from org.python.modules.io._io; although reasonable enough for Jython
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itself, we found that extant Python code expected that the _io module
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was the one defining various classes and constants. See
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http://bugs.jython.org/issue2368 for more background. If we ever get
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around to rewriting this module completely to Java, which is doubtful,
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this problem will go away.)
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Some classes have gained an underscore to match their _io module names:
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_IOBase, _RawIOBase, _BufferedIOBase, _TextIOBase.
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As Jython implements more and more of _io in Java, the Python implementations here
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will progressively be replaced with imports from _io. Eventually we should implement
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all this in Java, remove this module and revert io.py to its CPython original.
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"""
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from __future__ import (print_function, unicode_literals)
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import os
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import abc
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import codecs
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import warnings
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import errno
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import array
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# Import thread instead of threading to reduce startup cost
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try:
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from thread import allocate_lock as Lock
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except ImportError:
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from dummy_thread import allocate_lock as Lock
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#import io
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#from io import (__all__, SEEK_SET, SEEK_CUR, SEEK_END)
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from errno import EINTR
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__metaclass__ = type
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# open() uses st_blksize whenever we can
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from _jyio import DEFAULT_BUFFER_SIZE
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# NOTE: Base classes defined here are registered with the "official" ABCs
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# defined in io.py.
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class BlockingIOError(IOError):
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"""Exception raised when I/O would block on a non-blocking I/O stream."""
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def __init__(self, errno, strerror, characters_written=0):
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super(IOError, self).__init__(errno, strerror)
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if not isinstance(characters_written, (int, long)):
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raise TypeError("characters_written must be a integer")
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self.characters_written = characters_written
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from _jyio import (open, UnsupportedOperation, _IOBase, _RawIOBase, FileIO)
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class _BufferedIOBase(_IOBase):
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"""Base class for buffered IO objects.
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The main difference with _RawIOBase is that the read() method
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supports omitting the size argument, and does not have a default
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implementation that defers to readinto().
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In addition, read(), readinto() and write() may raise
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BlockingIOError if the underlying raw stream is in non-blocking
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mode and not ready; unlike their raw counterparts, they will never
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return None.
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A typical implementation should not inherit from a _RawIOBase
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implementation, but wrap one.
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"""
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def read(self, n=None):
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"""Read and return up to n bytes.
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If the argument is omitted, None, or negative, reads and
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returns all data until EOF.
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If the argument is positive, and the underlying raw stream is
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not 'interactive', multiple raw reads may be issued to satisfy
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the byte count (unless EOF is reached first). But for
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interactive raw streams (XXX and for pipes?), at most one raw
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read will be issued, and a short result does not imply that
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EOF is imminent.
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Returns an empty bytes array on EOF.
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Raises BlockingIOError if the underlying raw stream has no
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data at the moment.
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"""
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self._unsupported("read")
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def read1(self, n=None):
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"""Read up to n bytes with at most one read() system call."""
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self._unsupported("read1")
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def readinto(self, b):
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"""Read up to len(b) bytes into b.
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Like read(), this may issue multiple reads to the underlying raw
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stream, unless the latter is 'interactive'.
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Returns the number of bytes read (0 for EOF).
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Raises BlockingIOError if the underlying raw stream has no
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data at the moment.
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"""
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# XXX This ought to work with anything that supports the buffer API
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data = self.read(len(b))
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n = len(data)
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try:
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b[:n] = data
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except TypeError as err:
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import array
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if not isinstance(b, array.array):
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raise err
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b[:n] = array.array(b'b', data)
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return n
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def write(self, b):
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"""Write the given buffer to the IO stream.
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Return the number of bytes written, which is never less than
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len(b).
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Raises BlockingIOError if the buffer is full and the
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underlying raw stream cannot accept more data at the moment.
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"""
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self._unsupported("write")
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def detach(self):
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"""
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Separate the underlying raw stream from the buffer and return it.
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After the raw stream has been detached, the buffer is in an unusable
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state.
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"""
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self._unsupported("detach")
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class _BufferedIOMixin(_BufferedIOBase):
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"""A mixin implementation of _BufferedIOBase with an underlying raw stream.
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This passes most requests on to the underlying raw stream. It
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does *not* provide implementations of read(), readinto() or
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write().
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"""
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def __init__(self, raw):
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self._ok = False # Jython: subclass __init__ must set when state valid
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self._raw = raw
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### Positioning ###
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def seek(self, pos, whence=0):
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new_position = self.raw.seek(pos, whence)
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if new_position < 0:
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raise IOError("seek() returned an invalid position")
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return new_position
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def tell(self):
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pos = self.raw.tell()
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if pos < 0:
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raise IOError("tell() returned an invalid position")
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return pos
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def truncate(self, pos=None):
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# Flush the stream. We're mixing buffered I/O with lower-level I/O,
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# and a flush may be necessary to synch both views of the current
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# file state.
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self.flush()
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if pos is None:
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pos = self.tell()
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# XXX: Should seek() be used, instead of passing the position
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# XXX directly to truncate?
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return self.raw.truncate(pos)
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### Flush and close ###
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def flush(self):
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if self.closed:
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raise ValueError("flush of closed file")
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self.raw.flush()
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def close(self):
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if self.raw is not None and not self.closed:
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try:
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# Jython difference: call super.close() which manages "closed to client" state,
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# and calls flush(), which may raise BlockingIOError or BrokenPipeError etc.
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super(_BufferedIOBase, self).close()
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finally:
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self.raw.close()
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def detach(self):
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if self.raw is None:
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raise ValueError("raw stream already detached")
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self.flush()
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raw = self._raw
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self._raw = None
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return raw
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### Inquiries ###
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def seekable(self):
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self._checkInitialized() # Jython: to forbid use in an invalid state
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return self.raw.seekable()
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def readable(self):
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self._checkInitialized() # Jython: to forbid use in an invalid state
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return self.raw.readable()
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def writable(self):
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self._checkInitialized() # Jython: to forbid use in an invalid state
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return self.raw.writable()
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@property
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def raw(self):
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return self._raw
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@property
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def closed(self):
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return self.raw.closed
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# Jython difference: emulate C implementation CHECK_INITIALIZED. This is for
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# compatibility, to pass test.test_io.CTextIOWrapperTest.test_initialization.
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def _checkInitialized(self):
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if not self._ok:
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if self.raw is None:
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raise ValueError("raw stream has been detached")
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else:
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raise ValueError("I/O operation on uninitialized object")
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@property
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def name(self):
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return self.raw.name
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@property
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def mode(self):
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return self.raw.mode
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def __repr__(self):
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clsname = self.__class__.__name__
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try:
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name = self.name
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except AttributeError:
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return "<_io.{0}>".format(clsname)
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else:
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return "<_io.{0} name={1!r}>".format(clsname, name)
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### Lower-level APIs ###
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def fileno(self):
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return self.raw.fileno()
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def isatty(self):
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return self.raw.isatty()
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class BytesIO(_BufferedIOBase):
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"""Buffered I/O implementation using an in-memory bytes buffer."""
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def __init__(self, initial_bytes=None):
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buf = bytearray()
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if initial_bytes is not None:
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buf.extend(initial_bytes)
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self._buffer = buf
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self._pos = 0
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# Jython: modelled after bytesio.c::bytesio_getstate
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def __getstate__(self):
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d = getattr(self, '__dict__', None)
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if d is not None :
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d = d.copy()
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return (self.getvalue(), self._pos, d)
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# Jython: modelled after bytesio.c::bytesio_setstate
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def __setstate__(self, state):
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if not isinstance(state, tuple) or len(state) < 3 :
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fmt = "%s.__setstate__ argument should be 3-tuple got %s"
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raise TypeError( fmt % (type(self), type(state)) )
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# Reset the object to its default state. This is only needed to handle
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# the case of repeated calls to __setstate__. */
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self._buffer = bytearray()
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self._pos = 0
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# Set the value of the internal buffer. If state[0] does not support the
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# buffer protocol, bytesio_write will raise the appropriate TypeError. */
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self.write(state[0]);
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# Carefully set the position value. Alternatively, we could use the seek
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# method instead of modifying self._pos directly to better protect the
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# object internal state against erroneous (or malicious) inputs. */
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p = state[1]
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if not isinstance(p, (int, long)) :
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fmt = "second item of state must be an integer, got %s"
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raise TypeError( fmt % type(p) )
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elif p < 0 :
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raise ValueError("position value cannot be negative")
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self._pos = p
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# Set the dictionary of the instance variables. */
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d = state[2]
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if not d is None :
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if isinstance(d, dict) :
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self.__dict__ = d
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else :
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fmt = "third item of state should be a dict, got %s"
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raise TypeError( fmt % type(d) )
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def getvalue(self):
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"""Return the bytes value (contents) of the buffer
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"""
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if self.closed:
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raise ValueError("getvalue on closed file")
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return bytes(self._buffer)
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def read(self, n=None):
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if self.closed:
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raise ValueError("read from closed file")
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if n is None:
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n = -1
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if not isinstance(n, (int, long)):
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raise TypeError("integer argument expected, got {0!r}".format(
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type(n)))
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if n < 0:
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n = len(self._buffer)
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if len(self._buffer) <= self._pos:
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return b""
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newpos = min(len(self._buffer), self._pos + n)
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b = self._buffer[self._pos : newpos]
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self._pos = newpos
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return bytes(b)
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def read1(self, n):
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"""This is the same as read.
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"""
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return self.read(n)
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def write(self, b):
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if self.closed:
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raise ValueError("write to closed file")
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if isinstance(b, unicode):
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raise TypeError("can't write unicode to binary stream")
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n = len(b)
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if n == 0:
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return 0
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pos = self._pos
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if pos > len(self._buffer):
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# Inserts null bytes between the current end of the file
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# and the new write position.
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padding = b'\x00' * (pos - len(self._buffer))
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self._buffer += padding
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self._buffer[pos:pos + n] = b
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self._pos += n
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return n
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def seek(self, pos, whence=0):
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if self.closed:
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|
raise ValueError("seek on closed file")
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try:
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pos.__index__
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except AttributeError:
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raise TypeError("an integer is required")
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if whence == 0:
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if pos < 0:
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raise ValueError("negative seek position %r" % (pos,))
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self._pos = pos
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elif whence == 1:
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self._pos = max(0, self._pos + pos)
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elif whence == 2:
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self._pos = max(0, len(self._buffer) + pos)
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else:
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raise ValueError("invalid whence value")
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return self._pos
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|
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def tell(self):
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if self.closed:
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raise ValueError("tell on closed file")
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return self._pos
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|
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|
def truncate(self, pos=None):
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if self.closed:
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raise ValueError("truncate on closed file")
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|
if pos is None:
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pos = self._pos
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|
else:
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try:
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pos.__index__
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except AttributeError:
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|
raise TypeError("an integer is required")
|
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if pos < 0:
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raise ValueError("negative truncate position %r" % (pos,))
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del self._buffer[pos:]
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return pos
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|
|
|
def readable(self):
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self._checkClosed()
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return True
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|
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|
def writable(self):
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self._checkClosed()
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return True
|
|
|
|
def seekable(self):
|
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self._checkClosed()
|
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return True
|
|
|
|
|
|
class BufferedReader(_BufferedIOMixin):
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|
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"""BufferedReader(raw[, buffer_size])
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|
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|
A buffer for a readable, sequential BaseRawIO object.
|
|
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The constructor creates a BufferedReader for the given readable raw
|
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stream and buffer_size. If buffer_size is omitted, DEFAULT_BUFFER_SIZE
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is used.
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"""
|
|
|
|
def __init__(self, raw, buffer_size=DEFAULT_BUFFER_SIZE):
|
|
"""Create a new buffered reader using the given readable raw IO object.
|
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"""
|
|
if not raw.readable():
|
|
raise IOError('"raw" argument must be readable.')
|
|
|
|
_BufferedIOMixin.__init__(self, raw)
|
|
if buffer_size <= 0:
|
|
raise ValueError("invalid buffer size")
|
|
self.buffer_size = buffer_size
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|
self._reset_read_buf()
|
|
self._read_lock = Lock()
|
|
self._ok = True # Jython: to enable use now in a valid state
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|
|
|
def _reset_read_buf(self):
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|
self._read_buf = b""
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|
self._read_pos = 0
|
|
|
|
def read(self, n=None):
|
|
"""Read n bytes.
|
|
|
|
Returns exactly n bytes of data unless the underlying raw IO
|
|
stream reaches EOF or if the call would block in non-blocking
|
|
mode. If n is negative, read until EOF or until read() would
|
|
block.
|
|
"""
|
|
self._checkReadable() # Jython: to forbid use in an invalid state
|
|
if n is not None and n < -1:
|
|
raise ValueError("invalid number of bytes to read")
|
|
with self._read_lock:
|
|
return self._read_unlocked(n)
|
|
|
|
def _read_unlocked(self, n=None):
|
|
nodata_val = b""
|
|
empty_values = (b"", None)
|
|
buf = self._read_buf
|
|
pos = self._read_pos
|
|
|
|
# Special case for when the number of bytes to read is unspecified.
|
|
if n is None or n == -1:
|
|
self._reset_read_buf()
|
|
chunks = [buf[pos:]] # Strip the consumed bytes.
|
|
current_size = 0
|
|
while True:
|
|
# Read until EOF or until read() would block.
|
|
try:
|
|
chunk = self.raw.read()
|
|
except IOError as e:
|
|
if e.errno != EINTR:
|
|
raise
|
|
continue
|
|
if chunk in empty_values:
|
|
nodata_val = chunk
|
|
break
|
|
current_size += len(chunk)
|
|
chunks.append(chunk)
|
|
return b"".join(chunks) or nodata_val
|
|
|
|
# The number of bytes to read is specified, return at most n bytes.
|
|
avail = len(buf) - pos # Length of the available buffered data.
|
|
if n <= avail:
|
|
# Fast path: the data to read is fully buffered.
|
|
self._read_pos += n
|
|
return buf[pos:pos+n]
|
|
# Slow path: read from the stream until enough bytes are read,
|
|
# or until an EOF occurs or until read() would block.
|
|
chunks = [buf[pos:]]
|
|
wanted = max(self.buffer_size, n)
|
|
while avail < n:
|
|
try:
|
|
chunk = self.raw.read(wanted)
|
|
except IOError as e:
|
|
if e.errno != EINTR:
|
|
raise
|
|
continue
|
|
if chunk in empty_values:
|
|
nodata_val = chunk
|
|
break
|
|
avail += len(chunk)
|
|
chunks.append(chunk)
|
|
# n is more then avail only when an EOF occurred or when
|
|
# read() would have blocked.
|
|
n = min(n, avail)
|
|
out = b"".join(chunks)
|
|
self._read_buf = out[n:] # Save the extra data in the buffer.
|
|
self._read_pos = 0
|
|
return out[:n] if out else nodata_val
|
|
|
|
def peek(self, n=0):
|
|
"""Returns buffered bytes without advancing the position.
|
|
|
|
The argument indicates a desired minimal number of bytes; we
|
|
do at most one raw read to satisfy it. We never return more
|
|
than self.buffer_size.
|
|
"""
|
|
with self._read_lock:
|
|
return self._peek_unlocked(n)
|
|
|
|
def _peek_unlocked(self, n=0):
|
|
want = min(n, self.buffer_size)
|
|
have = len(self._read_buf) - self._read_pos
|
|
if have < want or have <= 0:
|
|
to_read = self.buffer_size - have
|
|
while True:
|
|
try:
|
|
current = self.raw.read(to_read)
|
|
except IOError as e:
|
|
if e.errno != EINTR:
|
|
raise
|
|
continue
|
|
break
|
|
if current:
|
|
self._read_buf = self._read_buf[self._read_pos:] + current
|
|
self._read_pos = 0
|
|
return self._read_buf[self._read_pos:]
|
|
|
|
def read1(self, n):
|
|
"""Reads up to n bytes, with at most one read() system call."""
|
|
# Returns up to n bytes. If at least one byte is buffered, we
|
|
# only return buffered bytes. Otherwise, we do one raw read.
|
|
self._checkReadable() # Jython: to forbid use in an invalid state
|
|
if n < 0:
|
|
raise ValueError("number of bytes to read must be positive")
|
|
if n == 0:
|
|
return b""
|
|
with self._read_lock:
|
|
self._peek_unlocked(1)
|
|
return self._read_unlocked(
|
|
min(n, len(self._read_buf) - self._read_pos))
|
|
|
|
def tell(self):
|
|
return _BufferedIOMixin.tell(self) - len(self._read_buf) + self._read_pos
|
|
|
|
def seek(self, pos, whence=0):
|
|
if not (0 <= whence <= 2):
|
|
raise ValueError("invalid whence value")
|
|
with self._read_lock:
|
|
if whence == 1:
|
|
pos -= len(self._read_buf) - self._read_pos
|
|
pos = _BufferedIOMixin.seek(self, pos, whence)
|
|
self._reset_read_buf()
|
|
return pos
|
|
|
|
|
|
class BufferedWriter(_BufferedIOMixin):
|
|
|
|
"""A buffer for a writeable sequential RawIO object.
|
|
|
|
The constructor creates a BufferedWriter for the given writeable raw
|
|
stream. If the buffer_size is not given, it defaults to
|
|
DEFAULT_BUFFER_SIZE.
|
|
"""
|
|
|
|
_warning_stack_offset = 2
|
|
|
|
def __init__(self, raw,
|
|
buffer_size=DEFAULT_BUFFER_SIZE, max_buffer_size=None):
|
|
if not raw.writable():
|
|
raise IOError('"raw" argument must be writable.')
|
|
|
|
_BufferedIOMixin.__init__(self, raw)
|
|
if buffer_size <= 0:
|
|
raise ValueError("invalid buffer size")
|
|
if max_buffer_size is not None:
|
|
warnings.warn("max_buffer_size is deprecated", DeprecationWarning,
|
|
self._warning_stack_offset)
|
|
self.buffer_size = buffer_size
|
|
self._write_buf = bytearray()
|
|
self._write_lock = Lock()
|
|
self._ok = True # Jython: to enable use now in a valid state
|
|
|
|
def write(self, b):
|
|
self._checkWritable() # Jython: to forbid use in an invalid state
|
|
if self.closed:
|
|
raise ValueError("write to closed file")
|
|
if isinstance(b, unicode):
|
|
raise TypeError("can't write unicode to binary stream")
|
|
with self._write_lock:
|
|
# XXX we can implement some more tricks to try and avoid
|
|
# partial writes
|
|
if len(self._write_buf) > self.buffer_size:
|
|
# We're full, so let's pre-flush the buffer. (This may
|
|
# raise BlockingIOError with characters_written == 0.)
|
|
self._flush_unlocked()
|
|
before = len(self._write_buf)
|
|
if isinstance(b, array.array): # _pyio.py version fails on array.array
|
|
self._write_buf.extend(b.tostring()) # Jython version works (while needed)
|
|
else:
|
|
self._write_buf.extend(b)
|
|
written = len(self._write_buf) - before
|
|
if len(self._write_buf) > self.buffer_size:
|
|
try:
|
|
self._flush_unlocked()
|
|
except BlockingIOError as e:
|
|
if len(self._write_buf) > self.buffer_size:
|
|
# We've hit the buffer_size. We have to accept a partial
|
|
# write and cut back our buffer.
|
|
overage = len(self._write_buf) - self.buffer_size
|
|
written -= overage
|
|
self._write_buf = self._write_buf[:self.buffer_size]
|
|
raise BlockingIOError(e.errno, e.strerror, written)
|
|
return written
|
|
|
|
def truncate(self, pos=None):
|
|
with self._write_lock:
|
|
self._flush_unlocked()
|
|
if pos is None:
|
|
pos = self.raw.tell()
|
|
return self.raw.truncate(pos)
|
|
|
|
def flush(self):
|
|
with self._write_lock:
|
|
self._flush_unlocked()
|
|
|
|
def _flush_unlocked(self):
|
|
if self.closed:
|
|
raise ValueError("flush of closed file")
|
|
self._checkWritable() # Jython: to forbid use in an invalid state
|
|
while self._write_buf:
|
|
try:
|
|
n = self.raw.write(self._write_buf)
|
|
except BlockingIOError:
|
|
raise RuntimeError("self.raw should implement _RawIOBase: it "
|
|
"should not raise BlockingIOError")
|
|
except IOError as e:
|
|
if e.errno != EINTR:
|
|
raise
|
|
continue
|
|
if n is None:
|
|
raise BlockingIOError(
|
|
errno.EAGAIN,
|
|
"write could not complete without blocking", 0)
|
|
if n > len(self._write_buf) or n < 0:
|
|
raise IOError("write() returned incorrect number of bytes")
|
|
del self._write_buf[:n]
|
|
|
|
def tell(self):
|
|
return _BufferedIOMixin.tell(self) + len(self._write_buf)
|
|
|
|
def seek(self, pos, whence=0):
|
|
if not (0 <= whence <= 2):
|
|
raise ValueError("invalid whence")
|
|
with self._write_lock:
|
|
self._flush_unlocked()
|
|
return _BufferedIOMixin.seek(self, pos, whence)
|
|
|
|
|
|
class BufferedRWPair(_BufferedIOBase):
|
|
|
|
"""A buffered reader and writer object together.
|
|
|
|
A buffered reader object and buffered writer object put together to
|
|
form a sequential IO object that can read and write. This is typically
|
|
used with a socket or two-way pipe.
|
|
|
|
reader and writer are _RawIOBase objects that are readable and
|
|
writeable respectively. If the buffer_size is omitted it defaults to
|
|
DEFAULT_BUFFER_SIZE.
|
|
"""
|
|
|
|
# XXX The usefulness of this (compared to having two separate IO
|
|
# objects) is questionable.
|
|
|
|
def __init__(self, reader, writer,
|
|
buffer_size=DEFAULT_BUFFER_SIZE, max_buffer_size=None):
|
|
"""Constructor.
|
|
|
|
The arguments are two RawIO instances.
|
|
"""
|
|
if max_buffer_size is not None:
|
|
warnings.warn("max_buffer_size is deprecated", DeprecationWarning, 2)
|
|
|
|
if not reader.readable():
|
|
raise IOError('"reader" argument must be readable.')
|
|
|
|
if not writer.writable():
|
|
raise IOError('"writer" argument must be writable.')
|
|
|
|
self.reader = BufferedReader(reader, buffer_size)
|
|
self.writer = BufferedWriter(writer, buffer_size)
|
|
|
|
def read(self, n=None):
|
|
if n is None:
|
|
n = -1
|
|
return self.reader.read(n)
|
|
|
|
def readinto(self, b):
|
|
return self.reader.readinto(b)
|
|
|
|
def write(self, b):
|
|
return self.writer.write(b)
|
|
|
|
def peek(self, n=0):
|
|
return self.reader.peek(n)
|
|
|
|
def read1(self, n):
|
|
return self.reader.read1(n)
|
|
|
|
def readable(self):
|
|
return self.reader.readable()
|
|
|
|
def writable(self):
|
|
return self.writer.writable()
|
|
|
|
def flush(self):
|
|
return self.writer.flush()
|
|
|
|
def close(self):
|
|
self.writer.close()
|
|
self.reader.close()
|
|
|
|
def isatty(self):
|
|
return self.reader.isatty() or self.writer.isatty()
|
|
|
|
@property
|
|
def closed(self):
|
|
return self.writer.closed
|
|
|
|
|
|
class BufferedRandom(BufferedWriter, BufferedReader):
|
|
|
|
"""A buffered interface to random access streams.
|
|
|
|
The constructor creates a reader and writer for a seekable stream,
|
|
raw, given in the first argument. If the buffer_size is omitted it
|
|
defaults to DEFAULT_BUFFER_SIZE.
|
|
"""
|
|
|
|
_warning_stack_offset = 3
|
|
|
|
def __init__(self, raw,
|
|
buffer_size=DEFAULT_BUFFER_SIZE, max_buffer_size=None):
|
|
raw._checkSeekable()
|
|
BufferedReader.__init__(self, raw, buffer_size)
|
|
BufferedWriter.__init__(self, raw, buffer_size, max_buffer_size)
|
|
|
|
def seek(self, pos, whence=0):
|
|
if not (0 <= whence <= 2):
|
|
raise ValueError("invalid whence")
|
|
self.flush()
|
|
if self._read_buf:
|
|
# Undo read ahead.
|
|
with self._read_lock:
|
|
self.raw.seek(self._read_pos - len(self._read_buf), 1)
|
|
# First do the raw seek, then empty the read buffer, so that
|
|
# if the raw seek fails, we don't lose buffered data forever.
|
|
pos = self.raw.seek(pos, whence)
|
|
with self._read_lock:
|
|
self._reset_read_buf()
|
|
if pos < 0:
|
|
raise IOError("seek() returned invalid position")
|
|
return pos
|
|
|
|
def tell(self):
|
|
if self._write_buf:
|
|
return BufferedWriter.tell(self)
|
|
else:
|
|
return BufferedReader.tell(self)
|
|
|
|
def truncate(self, pos=None):
|
|
if pos is None:
|
|
pos = self.tell()
|
|
# Use seek to flush the read buffer.
|
|
return BufferedWriter.truncate(self, pos)
|
|
|
|
def read(self, n=None):
|
|
if n is None:
|
|
n = -1
|
|
self.flush()
|
|
return BufferedReader.read(self, n)
|
|
|
|
def readinto(self, b):
|
|
self.flush()
|
|
return BufferedReader.readinto(self, b)
|
|
|
|
def peek(self, n=0):
|
|
self.flush()
|
|
return BufferedReader.peek(self, n)
|
|
|
|
def read1(self, n):
|
|
self.flush()
|
|
return BufferedReader.read1(self, n)
|
|
|
|
def write(self, b):
|
|
if self._read_buf:
|
|
# Undo readahead
|
|
with self._read_lock:
|
|
self.raw.seek(self._read_pos - len(self._read_buf), 1)
|
|
self._reset_read_buf()
|
|
return BufferedWriter.write(self, b)
|
|
|
|
|
|
class _TextIOBase(_IOBase):
|
|
|
|
"""Base class for text I/O.
|
|
|
|
This class provides a character and line based interface to stream
|
|
I/O. There is no readinto method because Python's character strings
|
|
are immutable. There is no public constructor.
|
|
"""
|
|
|
|
def read(self, n=-1):
|
|
"""Read at most n characters from stream.
|
|
|
|
Read from underlying buffer until we have n characters or we hit EOF.
|
|
If n is negative or omitted, read until EOF.
|
|
"""
|
|
self._unsupported("read")
|
|
|
|
def write(self, s):
|
|
"""Write string s to stream."""
|
|
self._unsupported("write")
|
|
|
|
def truncate(self, pos=None):
|
|
"""Truncate size to pos."""
|
|
self._unsupported("truncate")
|
|
|
|
def readline(self):
|
|
"""Read until newline or EOF.
|
|
|
|
Returns an empty string if EOF is hit immediately.
|
|
"""
|
|
self._unsupported("readline")
|
|
|
|
def detach(self):
|
|
"""
|
|
Separate the underlying buffer from the _TextIOBase and return it.
|
|
|
|
After the underlying buffer has been detached, the TextIO is in an
|
|
unusable state.
|
|
"""
|
|
self._unsupported("detach")
|
|
|
|
@property
|
|
def encoding(self):
|
|
"""Subclasses should override."""
|
|
return None
|
|
|
|
@property
|
|
def newlines(self):
|
|
"""Line endings translated so far.
|
|
|
|
Only line endings translated during reading are considered.
|
|
|
|
Subclasses should override.
|
|
"""
|
|
return None
|
|
|
|
@property
|
|
def errors(self):
|
|
"""Error setting of the decoder or encoder.
|
|
|
|
Subclasses should override."""
|
|
return None
|
|
|
|
|
|
class IncrementalNewlineDecoder(codecs.IncrementalDecoder):
|
|
r"""Codec used when reading a file in universal newlines mode. It wraps
|
|
another incremental decoder, translating \r\n and \r into \n. It also
|
|
records the types of newlines encountered. When used with
|
|
translate=False, it ensures that the newline sequence is returned in
|
|
one piece.
|
|
"""
|
|
def __init__(self, decoder, translate, errors='strict'):
|
|
codecs.IncrementalDecoder.__init__(self, errors=errors)
|
|
self.translate = translate
|
|
self.decoder = decoder
|
|
self.seennl = 0
|
|
self.pendingcr = False
|
|
|
|
def decode(self, input, final=False):
|
|
# decode input (with the eventual \r from a previous pass)
|
|
if self.decoder is None:
|
|
output = input
|
|
else:
|
|
output = self.decoder.decode(input, final=final)
|
|
if self.pendingcr and (output or final):
|
|
output = "\r" + output
|
|
self.pendingcr = False
|
|
|
|
# retain last \r even when not translating data:
|
|
# then readline() is sure to get \r\n in one pass
|
|
if output.endswith("\r") and not final:
|
|
output = output[:-1]
|
|
self.pendingcr = True
|
|
|
|
# Record which newlines are read
|
|
crlf = output.count('\r\n')
|
|
cr = output.count('\r') - crlf
|
|
lf = output.count('\n') - crlf
|
|
self.seennl |= (lf and self._LF) | (cr and self._CR) \
|
|
| (crlf and self._CRLF)
|
|
|
|
if self.translate:
|
|
if crlf:
|
|
output = output.replace("\r\n", "\n")
|
|
if cr:
|
|
output = output.replace("\r", "\n")
|
|
|
|
return output
|
|
|
|
def getstate(self):
|
|
if self.decoder is None:
|
|
buf = b""
|
|
flag = 0
|
|
else:
|
|
buf, flag = self.decoder.getstate()
|
|
flag <<= 1
|
|
if self.pendingcr:
|
|
flag |= 1
|
|
return buf, flag
|
|
|
|
def setstate(self, state):
|
|
buf, flag = state
|
|
self.pendingcr = bool(flag & 1)
|
|
if self.decoder is not None:
|
|
self.decoder.setstate((buf, flag >> 1))
|
|
|
|
def reset(self):
|
|
self.seennl = 0
|
|
self.pendingcr = False
|
|
if self.decoder is not None:
|
|
self.decoder.reset()
|
|
|
|
_LF = 1
|
|
_CR = 2
|
|
_CRLF = 4
|
|
|
|
@property
|
|
def newlines(self):
|
|
return (None,
|
|
"\n",
|
|
"\r",
|
|
("\r", "\n"),
|
|
"\r\n",
|
|
("\n", "\r\n"),
|
|
("\r", "\r\n"),
|
|
("\r", "\n", "\r\n")
|
|
)[self.seennl]
|
|
|
|
|
|
def _check_decoded_chars(chars):
|
|
"""Check decoder output is unicode"""
|
|
if not isinstance(chars, unicode):
|
|
raise TypeError("decoder should return a string result, not '%s'" %
|
|
type(chars))
|
|
|
|
def _check_buffered_bytes(b, context="read"):
|
|
"""Check buffer has returned bytes"""
|
|
if not isinstance(b, str):
|
|
raise TypeError("underlying %s() should have returned a bytes object, not '%s'" %
|
|
(context, type(b)))
|
|
|
|
|
|
|
|
class TextIOWrapper(_TextIOBase):
|
|
|
|
r"""Character and line based layer over a _BufferedIOBase object, buffer.
|
|
|
|
encoding gives the name of the encoding that the stream will be
|
|
decoded or encoded with. It defaults to locale.getpreferredencoding.
|
|
|
|
errors determines the strictness of encoding and decoding (see the
|
|
codecs.register) and defaults to "strict".
|
|
|
|
newline can be None, '', '\n', '\r', or '\r\n'. It controls the
|
|
handling of line endings. If it is None, universal newlines is
|
|
enabled. With this enabled, on input, the lines endings '\n', '\r',
|
|
or '\r\n' are translated to '\n' before being returned to the
|
|
caller. Conversely, on output, '\n' is translated to the system
|
|
default line separator, os.linesep. If newline is any other of its
|
|
legal values, that newline becomes the newline when the file is read
|
|
and it is returned untranslated. On output, '\n' is converted to the
|
|
newline.
|
|
|
|
If line_buffering is True, a call to flush is implied when a call to
|
|
write contains a newline character.
|
|
"""
|
|
|
|
_CHUNK_SIZE = 2048
|
|
|
|
def __init__(self, buffer, encoding=None, errors=None, newline=None,
|
|
line_buffering=False):
|
|
self._ok = False # Jython: to forbid use in an invalid state
|
|
if newline is not None and not isinstance(newline, basestring):
|
|
raise TypeError("illegal newline type: %r" % (type(newline),))
|
|
if newline not in (None, "", "\n", "\r", "\r\n"):
|
|
raise ValueError("illegal newline value: %r" % (newline,))
|
|
if encoding is None:
|
|
try:
|
|
import locale
|
|
except ImportError:
|
|
# Importing locale may fail if Python is being built
|
|
encoding = "ascii"
|
|
else:
|
|
encoding = locale.getpreferredencoding()
|
|
|
|
if not isinstance(encoding, basestring):
|
|
raise ValueError("invalid encoding: %r" % encoding)
|
|
|
|
if errors is None:
|
|
errors = "strict"
|
|
else:
|
|
if not isinstance(errors, basestring):
|
|
raise ValueError("invalid errors: %r" % errors)
|
|
|
|
self._buffer = buffer
|
|
self._line_buffering = line_buffering
|
|
self._encoding = encoding
|
|
self._errors = errors
|
|
self._readuniversal = not newline
|
|
self._readtranslate = newline is None
|
|
self._readnl = newline
|
|
self._writetranslate = newline != ''
|
|
self._writenl = newline or os.linesep
|
|
self._encoder = None
|
|
self._decoder = None
|
|
self._decoded_chars = '' # buffer for text returned from decoder
|
|
self._decoded_chars_used = 0 # offset into _decoded_chars for read()
|
|
self._snapshot = None # info for reconstructing decoder state
|
|
self._seekable = self._telling = self.buffer.seekable()
|
|
|
|
self._ok = True # Jython: to enable use now in a valid state
|
|
|
|
if self._seekable and self.writable():
|
|
position = self.buffer.tell()
|
|
if position != 0:
|
|
try:
|
|
self._get_encoder().setstate(0)
|
|
except LookupError:
|
|
# Sometimes the encoder doesn't exist
|
|
pass
|
|
|
|
# self._snapshot is either None, or a tuple (dec_flags, next_input)
|
|
# where dec_flags is the second (integer) item of the decoder state
|
|
# and next_input is the chunk of input bytes that comes next after the
|
|
# snapshot point. We use this to reconstruct decoder states in tell().
|
|
|
|
# Naming convention:
|
|
# - "bytes_..." for integer variables that count input bytes
|
|
# - "chars_..." for integer variables that count decoded characters
|
|
|
|
def __repr__(self):
|
|
try:
|
|
name = self.name
|
|
except AttributeError:
|
|
return "<_io.TextIOWrapper encoding='{0}'>".format(self.encoding)
|
|
else:
|
|
return "<_io.TextIOWrapper name={0!r} encoding='{1}'>".format(
|
|
name, self.encoding)
|
|
|
|
@property
|
|
def encoding(self):
|
|
return self._encoding
|
|
|
|
@property
|
|
def errors(self):
|
|
return self._errors
|
|
|
|
@property
|
|
def line_buffering(self):
|
|
return self._line_buffering
|
|
|
|
@property
|
|
def buffer(self):
|
|
return self._buffer
|
|
|
|
def seekable(self):
|
|
self._checkInitialized() # Jython: to forbid use in an invalid state
|
|
self._checkClosed()
|
|
return self._seekable
|
|
|
|
def readable(self):
|
|
self._checkInitialized() # Jython: to forbid use in an invalid state
|
|
return self.buffer.readable()
|
|
|
|
def writable(self):
|
|
self._checkInitialized() # Jython: to forbid use in an invalid state
|
|
return self.buffer.writable()
|
|
|
|
def flush(self):
|
|
self._checkInitialized() # Jython: to forbid use in an invalid state
|
|
self.buffer.flush()
|
|
self._telling = self._seekable
|
|
|
|
def close(self):
|
|
if self.buffer is not None and not self.closed:
|
|
try:
|
|
# Jython difference: flush and close via super.
|
|
# Sets __closed for quick _checkClosed().
|
|
super(TextIOWrapper, self).close()
|
|
finally:
|
|
self.buffer.close()
|
|
|
|
@property
|
|
def closed(self):
|
|
return self.buffer.closed
|
|
|
|
# Jython difference: emulate C implementation CHECK_INITIALIZED. This is for
|
|
# compatibility, to pass test.test_io.CTextIOWrapperTest.test_initialization.
|
|
def _checkInitialized(self):
|
|
if not self._ok:
|
|
if self.buffer is None:
|
|
raise ValueError("underlying buffer has been detached")
|
|
else:
|
|
raise ValueError("I/O operation on uninitialized object")
|
|
|
|
@property
|
|
def name(self):
|
|
return self.buffer.name
|
|
|
|
def fileno(self):
|
|
return self.buffer.fileno()
|
|
|
|
def isatty(self):
|
|
return self.buffer.isatty()
|
|
|
|
def write(self, s):
|
|
self._checkWritable() # Jython: to forbid use in an invalid state
|
|
if self.closed:
|
|
raise ValueError("write to closed file")
|
|
if not isinstance(s, unicode):
|
|
raise TypeError("can't write %s to text stream" %
|
|
s.__class__.__name__)
|
|
length = len(s)
|
|
haslf = (self._writetranslate or self._line_buffering) and "\n" in s
|
|
if haslf and self._writetranslate and self._writenl != "\n":
|
|
s = s.replace("\n", self._writenl)
|
|
encoder = self._encoder or self._get_encoder()
|
|
# XXX What if we were just reading?
|
|
b = encoder.encode(s)
|
|
self.buffer.write(b)
|
|
if self._line_buffering and (haslf or "\r" in s):
|
|
self.flush()
|
|
self._snapshot = None
|
|
if self._decoder:
|
|
self._decoder.reset()
|
|
return length
|
|
|
|
def _get_encoder(self):
|
|
make_encoder = codecs.getincrementalencoder(self._encoding)
|
|
self._encoder = make_encoder(self._errors)
|
|
return self._encoder
|
|
|
|
def _get_decoder(self):
|
|
make_decoder = codecs.getincrementaldecoder(self._encoding)
|
|
decoder = make_decoder(self._errors)
|
|
if self._readuniversal:
|
|
decoder = IncrementalNewlineDecoder(decoder, self._readtranslate)
|
|
self._decoder = decoder
|
|
return decoder
|
|
|
|
# The following three methods implement an ADT for _decoded_chars.
|
|
# Text returned from the decoder is buffered here until the client
|
|
# requests it by calling our read() or readline() method.
|
|
def _set_decoded_chars(self, chars):
|
|
"""Set the _decoded_chars buffer."""
|
|
self._decoded_chars = chars
|
|
self._decoded_chars_used = 0
|
|
|
|
def _get_decoded_chars(self, n=None):
|
|
"""Advance into the _decoded_chars buffer."""
|
|
offset = self._decoded_chars_used
|
|
if n is None:
|
|
chars = self._decoded_chars[offset:]
|
|
else:
|
|
chars = self._decoded_chars[offset:offset + n]
|
|
self._decoded_chars_used += len(chars)
|
|
return chars
|
|
|
|
def _rewind_decoded_chars(self, n):
|
|
"""Rewind the _decoded_chars buffer."""
|
|
if self._decoded_chars_used < n:
|
|
raise AssertionError("rewind decoded_chars out of bounds")
|
|
self._decoded_chars_used -= n
|
|
|
|
def _read_chunk(self):
|
|
"""
|
|
Read and decode the next chunk of data from the BufferedReader.
|
|
"""
|
|
|
|
# The return value is True unless EOF was reached. The decoded
|
|
# string is placed in self._decoded_chars (replacing its previous
|
|
# value). The entire input chunk is sent to the decoder, though
|
|
# some of it may remain buffered in the decoder, yet to be
|
|
# converted.
|
|
|
|
if self._decoder is None:
|
|
raise ValueError("no decoder")
|
|
|
|
if self._telling:
|
|
# To prepare for tell(), we need to snapshot a point in the
|
|
# file where the decoder's input buffer is empty.
|
|
|
|
dec_buffer, dec_flags = self._decoder.getstate()
|
|
# Given this, we know there was a valid snapshot point
|
|
# len(dec_buffer) bytes ago with decoder state (b'', dec_flags).
|
|
|
|
# Read a chunk, decode it, and put the result in self._decoded_chars.
|
|
input_chunk = self.buffer.read1(self._CHUNK_SIZE)
|
|
_check_buffered_bytes(input_chunk, "read1")
|
|
|
|
eof = not input_chunk
|
|
decoded_chunk = self._decoder.decode(input_chunk, eof)
|
|
_check_decoded_chars(decoded_chunk)
|
|
self._set_decoded_chars(decoded_chunk)
|
|
|
|
if self._telling:
|
|
# At the snapshot point, len(dec_buffer) bytes before the read,
|
|
# the next input to be decoded is dec_buffer + input_chunk.
|
|
self._snapshot = (dec_flags, dec_buffer + input_chunk)
|
|
|
|
return not eof
|
|
|
|
def _pack_cookie(self, position, dec_flags=0,
|
|
bytes_to_feed=0, need_eof=0, chars_to_skip=0):
|
|
# The meaning of a tell() cookie is: seek to position, set the
|
|
# decoder flags to dec_flags, read bytes_to_feed bytes, feed them
|
|
# into the decoder with need_eof as the EOF flag, then skip
|
|
# chars_to_skip characters of the decoded result. For most simple
|
|
# decoders, tell() will often just give a byte offset in the file.
|
|
return (position | (dec_flags<<64) | (bytes_to_feed<<128) |
|
|
(chars_to_skip<<192) | bool(need_eof)<<256)
|
|
|
|
def _unpack_cookie(self, bigint):
|
|
rest, position = divmod(bigint, 1<<64)
|
|
rest, dec_flags = divmod(rest, 1<<64)
|
|
rest, bytes_to_feed = divmod(rest, 1<<64)
|
|
need_eof, chars_to_skip = divmod(rest, 1<<64)
|
|
return position, dec_flags, bytes_to_feed, need_eof, chars_to_skip
|
|
|
|
def tell(self):
|
|
if not self._seekable:
|
|
raise IOError("underlying stream is not seekable")
|
|
if not self._telling:
|
|
raise IOError("telling position disabled by next() call")
|
|
self.flush()
|
|
position = self.buffer.tell()
|
|
decoder = self._decoder
|
|
if decoder is None or self._snapshot is None:
|
|
if self._decoded_chars:
|
|
# This should never happen.
|
|
raise AssertionError("pending decoded text")
|
|
return position
|
|
|
|
# Skip backward to the snapshot point (see _read_chunk).
|
|
dec_flags, next_input = self._snapshot
|
|
position -= len(next_input)
|
|
|
|
# How many decoded characters have been used up since the snapshot?
|
|
chars_to_skip = self._decoded_chars_used
|
|
if chars_to_skip == 0:
|
|
# We haven't moved from the snapshot point.
|
|
return self._pack_cookie(position, dec_flags)
|
|
|
|
# Starting from the snapshot position, we will walk the decoder
|
|
# forward until it gives us enough decoded characters.
|
|
saved_state = decoder.getstate()
|
|
try:
|
|
# Note our initial start point.
|
|
decoder.setstate((b'', dec_flags))
|
|
start_pos = position
|
|
start_flags, bytes_fed, chars_decoded = dec_flags, 0, 0
|
|
need_eof = 0
|
|
|
|
# Feed the decoder one byte at a time. As we go, note the
|
|
# nearest "safe start point" before the current location
|
|
# (a point where the decoder has nothing buffered, so seek()
|
|
# can safely start from there and advance to this location).
|
|
for next_byte in next_input:
|
|
bytes_fed += 1
|
|
chars_decoded += len(decoder.decode(next_byte))
|
|
dec_buffer, dec_flags = decoder.getstate()
|
|
if not dec_buffer and chars_decoded <= chars_to_skip:
|
|
# Decoder buffer is empty, so this is a safe start point.
|
|
start_pos += bytes_fed
|
|
chars_to_skip -= chars_decoded
|
|
start_flags, bytes_fed, chars_decoded = dec_flags, 0, 0
|
|
if chars_decoded >= chars_to_skip:
|
|
break
|
|
else:
|
|
# We didn't get enough decoded data; signal EOF to get more.
|
|
chars_decoded += len(decoder.decode(b'', final=True))
|
|
need_eof = 1
|
|
if chars_decoded < chars_to_skip:
|
|
raise IOError("can't reconstruct logical file position")
|
|
|
|
# The returned cookie corresponds to the last safe start point.
|
|
return self._pack_cookie(
|
|
start_pos, start_flags, bytes_fed, need_eof, chars_to_skip)
|
|
finally:
|
|
decoder.setstate(saved_state)
|
|
|
|
def truncate(self, pos=None):
|
|
self.flush()
|
|
if pos is None:
|
|
pos = self.tell()
|
|
return self.buffer.truncate(pos)
|
|
|
|
def detach(self):
|
|
if self.buffer is None:
|
|
raise ValueError("buffer is already detached")
|
|
self.flush()
|
|
self._ok = False # Jython: to forbid use in an invalid state
|
|
buffer = self._buffer
|
|
self._buffer = None
|
|
return buffer
|
|
|
|
def seek(self, cookie, whence=0):
|
|
if self.closed:
|
|
raise ValueError("tell on closed file")
|
|
if not self._seekable:
|
|
raise IOError("underlying stream is not seekable")
|
|
if whence == 1: # seek relative to current position
|
|
if cookie != 0:
|
|
raise IOError("can't do nonzero cur-relative seeks")
|
|
# Seeking to the current position should attempt to
|
|
# sync the underlying buffer with the current position.
|
|
whence = 0
|
|
cookie = self.tell()
|
|
if whence == 2: # seek relative to end of file
|
|
if cookie != 0:
|
|
raise IOError("can't do nonzero end-relative seeks")
|
|
self.flush()
|
|
position = self.buffer.seek(0, 2)
|
|
self._set_decoded_chars('')
|
|
self._snapshot = None
|
|
if self._decoder:
|
|
self._decoder.reset()
|
|
return position
|
|
if whence != 0:
|
|
raise ValueError("invalid whence (%r, should be 0, 1 or 2)" %
|
|
(whence,))
|
|
if cookie < 0:
|
|
raise ValueError("negative seek position %r" % (cookie,))
|
|
self.flush()
|
|
|
|
# The strategy of seek() is to go back to the safe start point
|
|
# and replay the effect of read(chars_to_skip) from there.
|
|
start_pos, dec_flags, bytes_to_feed, need_eof, chars_to_skip = \
|
|
self._unpack_cookie(cookie)
|
|
|
|
# Seek back to the safe start point.
|
|
self.buffer.seek(start_pos)
|
|
self._set_decoded_chars('')
|
|
self._snapshot = None
|
|
|
|
# Restore the decoder to its state from the safe start point.
|
|
if cookie == 0 and self._decoder:
|
|
self._decoder.reset()
|
|
elif self._decoder or dec_flags or chars_to_skip:
|
|
self._decoder = self._decoder or self._get_decoder()
|
|
self._decoder.setstate((b'', dec_flags))
|
|
self._snapshot = (dec_flags, b'')
|
|
|
|
if chars_to_skip:
|
|
# Just like _read_chunk, feed the decoder and save a snapshot.
|
|
input_chunk = self.buffer.read(bytes_to_feed)
|
|
_check_buffered_bytes(input_chunk)
|
|
decoded_chunk = self._decoder.decode(input_chunk, need_eof)
|
|
_check_decoded_chars(decoded_chunk)
|
|
self._set_decoded_chars(decoded_chunk)
|
|
|
|
self._snapshot = (dec_flags, input_chunk)
|
|
|
|
# Skip chars_to_skip of the decoded characters.
|
|
if len(self._decoded_chars) < chars_to_skip:
|
|
raise IOError("can't restore logical file position")
|
|
self._decoded_chars_used = chars_to_skip
|
|
|
|
# Finally, reset the encoder (merely useful for proper BOM handling)
|
|
try:
|
|
encoder = self._encoder or self._get_encoder()
|
|
except LookupError:
|
|
# Sometimes the encoder doesn't exist
|
|
pass
|
|
else:
|
|
if cookie != 0:
|
|
encoder.setstate(0)
|
|
else:
|
|
encoder.reset()
|
|
return cookie
|
|
|
|
def read(self, n=None):
|
|
self._checkReadable()
|
|
if n is None:
|
|
n = -1
|
|
decoder = self._decoder or self._get_decoder()
|
|
try:
|
|
n.__index__
|
|
except AttributeError:
|
|
raise TypeError("an integer is required")
|
|
if n < 0:
|
|
# Read everything.
|
|
input_chunk = self.buffer.read()
|
|
# Jython difference: CPython textio.c omits:
|
|
_check_buffered_bytes(input_chunk)
|
|
decoded_chunk = decoder.decode(input_chunk, final=True)
|
|
_check_decoded_chars(decoded_chunk)
|
|
result = self._get_decoded_chars() + decoded_chunk
|
|
self._set_decoded_chars('')
|
|
self._snapshot = None
|
|
return result
|
|
else:
|
|
# Keep reading chunks until we have n characters to return.
|
|
eof = False
|
|
result = self._get_decoded_chars(n)
|
|
while len(result) < n and not eof:
|
|
eof = not self._read_chunk()
|
|
result += self._get_decoded_chars(n - len(result))
|
|
return result
|
|
|
|
def next(self):
|
|
self._telling = False
|
|
line = self.readline()
|
|
if not line:
|
|
self._snapshot = None
|
|
self._telling = self._seekable
|
|
raise StopIteration
|
|
return line
|
|
|
|
def readline(self, limit=None):
|
|
if self.closed:
|
|
raise ValueError("read from closed file")
|
|
if limit is None:
|
|
limit = -1
|
|
elif not isinstance(limit, (int, long)):
|
|
raise TypeError("limit must be an integer")
|
|
|
|
# Grab all the decoded text (we will rewind any extra bits later).
|
|
line = self._get_decoded_chars()
|
|
|
|
start = 0
|
|
# Make the decoder if it doesn't already exist.
|
|
if not self._decoder:
|
|
self._get_decoder()
|
|
|
|
pos = endpos = None
|
|
while True:
|
|
if self._readtranslate:
|
|
# Newlines are already translated, only search for \n
|
|
pos = line.find('\n', start)
|
|
if pos >= 0:
|
|
endpos = pos + 1
|
|
break
|
|
else:
|
|
start = len(line)
|
|
|
|
elif self._readuniversal:
|
|
# Universal newline search. Find any of \r, \r\n, \n
|
|
# The decoder ensures that \r\n are not split in two pieces
|
|
|
|
# In C we'd look for these in parallel of course.
|
|
nlpos = line.find("\n", start)
|
|
crpos = line.find("\r", start)
|
|
if crpos == -1:
|
|
if nlpos == -1:
|
|
# Nothing found
|
|
start = len(line)
|
|
else:
|
|
# Found \n
|
|
endpos = nlpos + 1
|
|
break
|
|
elif nlpos == -1:
|
|
# Found lone \r
|
|
endpos = crpos + 1
|
|
break
|
|
elif nlpos < crpos:
|
|
# Found \n
|
|
endpos = nlpos + 1
|
|
break
|
|
elif nlpos == crpos + 1:
|
|
# Found \r\n
|
|
endpos = crpos + 2
|
|
break
|
|
else:
|
|
# Found \r
|
|
endpos = crpos + 1
|
|
break
|
|
else:
|
|
# non-universal
|
|
pos = line.find(self._readnl)
|
|
if pos >= 0:
|
|
endpos = pos + len(self._readnl)
|
|
break
|
|
|
|
if limit >= 0 and len(line) >= limit:
|
|
endpos = limit # reached length limit
|
|
break
|
|
|
|
# No line ending seen yet - get more data'
|
|
while self._read_chunk():
|
|
if self._decoded_chars:
|
|
break
|
|
if self._decoded_chars:
|
|
line += self._get_decoded_chars()
|
|
else:
|
|
# end of file
|
|
self._set_decoded_chars('')
|
|
self._snapshot = None
|
|
return line
|
|
|
|
if limit >= 0 and endpos > limit:
|
|
endpos = limit # don't exceed limit
|
|
|
|
# Rewind _decoded_chars to just after the line ending we found.
|
|
self._rewind_decoded_chars(len(line) - endpos)
|
|
return line[:endpos]
|
|
|
|
@property
|
|
def newlines(self):
|
|
return self._decoder.newlines if self._decoder else None
|
|
|
|
|
|
class StringIO(TextIOWrapper):
|
|
"""Text I/O implementation using an in-memory buffer.
|
|
|
|
The initial_value argument sets the value of object. The newline
|
|
argument is like the one of TextIOWrapper's constructor.
|
|
"""
|
|
|
|
def __init__(self, initial_value="", newline="\n"):
|
|
|
|
# Newline mark needs to be in bytes: convert if not already so
|
|
if isinstance(newline, unicode) :
|
|
newline = newline.encode("utf-8")
|
|
|
|
super(StringIO, self).__init__(BytesIO(),
|
|
encoding="utf-8",
|
|
errors="strict",
|
|
newline=newline)
|
|
# Issue #5645: make universal newlines semantics the same as in the
|
|
# C version, even under Windows.
|
|
if newline is None:
|
|
self._writetranslate = False
|
|
# An initial value may have been supplied (and must be unicode)
|
|
if initial_value is not None:
|
|
if not isinstance(initial_value, unicode) :
|
|
fmt = "initial value should be unicode or None, got %s"
|
|
raise TypeError( fmt % type(initial_value) )
|
|
if initial_value:
|
|
self.write(initial_value)
|
|
self.seek(0)
|
|
|
|
# Jython: modelled after stringio.c::stringio_getstate
|
|
def __getstate__(self):
|
|
d = getattr(self, '__dict__', None)
|
|
if d is not None :
|
|
d = d.copy()
|
|
return (self.getvalue(), self._readnl, self.tell(), d)
|
|
|
|
# Jython: modelled after stringio.c:stringio_setstate
|
|
def __setstate__(self, state):
|
|
self._checkClosed()
|
|
|
|
if not isinstance(state, tuple) or len(state) < 4 :
|
|
fmt = "%s.__setstate__ argument should be 4-tuple got %s"
|
|
raise TypeError( fmt % (type(self), type(state)) )
|
|
|
|
# Initialize the object's state, but empty
|
|
self.__init__(None, state[1])
|
|
|
|
# Write the buffer, bypassing end-of-line translation.
|
|
value = state[0]
|
|
if value is not None:
|
|
if not isinstance(value, unicode) :
|
|
fmt = "ivalue should be unicode or None, got %s"
|
|
raise TypeError( fmt % type(value) )
|
|
encoder = self._encoder or self._get_encoder()
|
|
b = encoder.encode(state[0])
|
|
self.buffer.write(b)
|
|
|
|
# Reset the object to its default state. This is only needed to handle
|
|
# the case of repeated calls to __setstate__.
|
|
self.seek(0)
|
|
|
|
# Set the position value using seek. A long is tolerated (e.g from pickle).
|
|
p = state[2]
|
|
if not isinstance(p, (int, long)) :
|
|
fmt = "third item of state must be an integer, got %s"
|
|
raise TypeError( fmt % type(p) )
|
|
elif p < 0 :
|
|
raise ValueError("position value cannot be negative")
|
|
self.seek(p)
|
|
|
|
# Set the dictionary of the instance variables. */
|
|
d = state[3]
|
|
if not d is None :
|
|
if isinstance(d, dict) :
|
|
self.__dict__ = d
|
|
else :
|
|
fmt = "fourth item of state should be a dict, got %s"
|
|
raise TypeError( fmt % type(d) )
|
|
|
|
def getvalue(self):
|
|
self.flush()
|
|
return self.buffer.getvalue().decode(self._encoding, self._errors)
|
|
|
|
def __repr__(self):
|
|
# TextIOWrapper tells the encoding in its repr. In StringIO,
|
|
# that's a implementation detail.
|
|
return object.__repr__(self)
|
|
|
|
@property
|
|
def errors(self):
|
|
return None
|
|
|
|
@property
|
|
def encoding(self):
|
|
return None
|
|
|
|
def detach(self):
|
|
# This doesn't make sense on StringIO.
|
|
self._unsupported("detach")
|