"""This is based on _pyio.py from CPython 2.7 which is Python implementation of
the io module. The upgrade from a 2.6-ish version accounts for the large
number of changes made all at once.
It is here to stand in for classes that should be provided by the Java
implementation of the _io module. In CPython 2.7, when client code
imports io, that module imports a set of classes from _io and
re-exports them as its own. In Jython, io.py imports those things from
_io, which in turn imports from _jyio those so far implemented in
Java. Consequently _io implements the rest here using nearly the same
code as _pyio. (Previous to Jython 2.7.1, the import was reversed:
this specific Python-based module was named _jyio, and it imported
from org.python.modules.io._io; although reasonable enough for Jython
itself, we found that extant Python code expected that the _io module
was the one defining various classes and constants. See
http://bugs.jython.org/issue2368 for more background. If we ever get
around to rewriting this module completely to Java, which is doubtful,
this problem will go away.)
Some classes have gained an underscore to match their _io module names:
_IOBase, _RawIOBase, _BufferedIOBase, _TextIOBase.
As Jython implements more and more of _io in Java, the Python implementations here
will progressively be replaced with imports from _io. Eventually we should implement
all this in Java, remove this module and revert io.py to its CPython original.
"""
from __future__ import (print_function, unicode_literals)
import os
import abc
import codecs
import warnings
import errno
import array
# Import thread instead of threading to reduce startup cost
try:
from thread import allocate_lock as Lock
except ImportError:
from dummy_thread import allocate_lock as Lock
#import io
#from io import (__all__, SEEK_SET, SEEK_CUR, SEEK_END)
from errno import EINTR
__metaclass__ = type
# open() uses st_blksize whenever we can
from _jyio import DEFAULT_BUFFER_SIZE
# NOTE: Base classes defined here are registered with the "official" ABCs
# defined in io.py.
class BlockingIOError(IOError):
"""Exception raised when I/O would block on a non-blocking I/O stream."""
def __init__(self, errno, strerror, characters_written=0):
super(IOError, self).__init__(errno, strerror)
if not isinstance(characters_written, (int, long)):
raise TypeError("characters_written must be a integer")
self.characters_written = characters_written
from _jyio import (open, UnsupportedOperation, _IOBase, _RawIOBase, FileIO)
class _BufferedIOBase(_IOBase):
"""Base class for buffered IO objects.
The main difference with _RawIOBase is that the read() method
supports omitting the size argument, and does not have a default
implementation that defers to readinto().
In addition, read(), readinto() and write() may raise
BlockingIOError if the underlying raw stream is in non-blocking
mode and not ready; unlike their raw counterparts, they will never
return None.
A typical implementation should not inherit from a _RawIOBase
implementation, but wrap one.
"""
def read(self, n=None):
"""Read and return up to n bytes.
If the argument is omitted, None, or negative, reads and
returns all data until EOF.
If the argument is positive, and the underlying raw stream is
not 'interactive', multiple raw reads may be issued to satisfy
the byte count (unless EOF is reached first). But for
interactive raw streams (XXX and for pipes?), at most one raw
read will be issued, and a short result does not imply that
EOF is imminent.
Returns an empty bytes array on EOF.
Raises BlockingIOError if the underlying raw stream has no
data at the moment.
"""
self._unsupported("read")
def read1(self, n=None):
"""Read up to n bytes with at most one read() system call."""
self._unsupported("read1")
def readinto(self, b):
"""Read up to len(b) bytes into b.
Like read(), this may issue multiple reads to the underlying raw
stream, unless the latter is 'interactive'.
Returns the number of bytes read (0 for EOF).
Raises BlockingIOError if the underlying raw stream has no
data at the moment.
"""
# XXX This ought to work with anything that supports the buffer API
data = self.read(len(b))
n = len(data)
try:
b[:n] = data
except TypeError as err:
import array
if not isinstance(b, array.array):
raise err
b[:n] = array.array(b'b', data)
return n
def write(self, b):
"""Write the given buffer to the IO stream.
Return the number of bytes written, which is never less than
len(b).
Raises BlockingIOError if the buffer is full and the
underlying raw stream cannot accept more data at the moment.
"""
self._unsupported("write")
def detach(self):
"""
Separate the underlying raw stream from the buffer and return it.
After the raw stream has been detached, the buffer is in an unusable
state.
"""
self._unsupported("detach")
class _BufferedIOMixin(_BufferedIOBase):
"""A mixin implementation of _BufferedIOBase with an underlying raw stream.
This passes most requests on to the underlying raw stream. It
does *not* provide implementations of read(), readinto() or
write().
"""
def __init__(self, raw):
self._ok = False # Jython: subclass __init__ must set when state valid
self._raw = raw
### Positioning ###
def seek(self, pos, whence=0):
new_position = self.raw.seek(pos, whence)
if new_position < 0:
raise IOError("seek() returned an invalid position")
return new_position
def tell(self):
pos = self.raw.tell()
if pos < 0:
raise IOError("tell() returned an invalid position")
return pos
def truncate(self, pos=None):
# Flush the stream. We're mixing buffered I/O with lower-level I/O,
# and a flush may be necessary to synch both views of the current
# file state.
self.flush()
if pos is None:
pos = self.tell()
# XXX: Should seek() be used, instead of passing the position
# XXX directly to truncate?
return self.raw.truncate(pos)
### Flush and close ###
def flush(self):
if self.closed:
raise ValueError("flush of closed file")
self.raw.flush()
def close(self):
if self.raw is not None and not self.closed:
try:
# Jython difference: call super.close() which manages "closed to client" state,
# and calls flush(), which may raise BlockingIOError or BrokenPipeError etc.
super(_BufferedIOBase, self).close()
finally:
self.raw.close()
def detach(self):
if self.raw is None:
raise ValueError("raw stream already detached")
self.flush()
raw = self._raw
self._raw = None
return raw
### Inquiries ###
def seekable(self):
self._checkInitialized() # Jython: to forbid use in an invalid state
return self.raw.seekable()
def readable(self):
self._checkInitialized() # Jython: to forbid use in an invalid state
return self.raw.readable()
def writable(self):
self._checkInitialized() # Jython: to forbid use in an invalid state
return self.raw.writable()
@property
def raw(self):
return self._raw
@property
def closed(self):
return self.raw.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.raw is None:
raise ValueError("raw stream has been detached")
else:
raise ValueError("I/O operation on uninitialized object")
@property
def name(self):
return self.raw.name
@property
def mode(self):
return self.raw.mode
def __repr__(self):
clsname = self.__class__.__name__
try:
name = self.name
except AttributeError:
return "<_io.{0}>".format(clsname)
else:
return "<_io.{0} name={1!r}>".format(clsname, name)
### Lower-level APIs ###
def fileno(self):
return self.raw.fileno()
def isatty(self):
return self.raw.isatty()
class BytesIO(_BufferedIOBase):
"""Buffered I/O implementation using an in-memory bytes buffer."""
def __init__(self, initial_bytes=None):
buf = bytearray()
if initial_bytes is not None:
buf.extend(initial_bytes)
self._buffer = buf
self._pos = 0
# Jython: modelled after bytesio.c::bytesio_getstate
def __getstate__(self):
d = getattr(self, '__dict__', None)
if d is not None :
d = d.copy()
return (self.getvalue(), self._pos, d)
# Jython: modelled after bytesio.c::bytesio_setstate
def __setstate__(self, state):
if not isinstance(state, tuple) or len(state) < 3 :
fmt = "%s.__setstate__ argument should be 3-tuple got %s"
raise TypeError( fmt % (type(self), type(state)) )
# Reset the object to its default state. This is only needed to handle
# the case of repeated calls to __setstate__. */
self._buffer = bytearray()
self._pos = 0
# Set the value of the internal buffer. If state[0] does not support the
# buffer protocol, bytesio_write will raise the appropriate TypeError. */
self.write(state[0]);
# Carefully set the position value. Alternatively, we could use the seek
# method instead of modifying self._pos directly to better protect the
# object internal state against erroneous (or malicious) inputs. */
p = state[1]
if not isinstance(p, (int, long)) :
fmt = "second 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._pos = p
# Set the dictionary of the instance variables. */
d = state[2]
if not d is None :
if isinstance(d, dict) :
self.__dict__ = d
else :
fmt = "third item of state should be a dict, got %s"
raise TypeError( fmt % type(d) )
def getvalue(self):
"""Return the bytes value (contents) of the buffer
"""
if self.closed:
raise ValueError("getvalue on closed file")
return bytes(self._buffer)
def read(self, n=None):
if self.closed:
raise ValueError("read from closed file")
if n is None:
n = -1
if not isinstance(n, (int, long)):
raise TypeError("integer argument expected, got {0!r}".format(
type(n)))
if n < 0:
n = len(self._buffer)
if len(self._buffer) <= self._pos:
return b""
newpos = min(len(self._buffer), self._pos + n)
b = self._buffer[self._pos : newpos]
self._pos = newpos
return bytes(b)
def read1(self, n):
"""This is the same as read.
"""
return self.read(n)
def write(self, b):
if self.closed:
raise ValueError("write to closed file")
if isinstance(b, unicode):
raise TypeError("can't write unicode to binary stream")
n = len(b)
if n == 0:
return 0
pos = self._pos
if pos > len(self._buffer):
# Inserts null bytes between the current end of the file
# and the new write position.
padding = b'\x00' * (pos - len(self._buffer))
self._buffer += padding
self._buffer[pos:pos + n] = b
self._pos += n
return n
def seek(self, pos, whence=0):
if self.closed:
raise ValueError("seek on closed file")
try:
pos.__index__
except AttributeError:
raise TypeError("an integer is required")
if whence == 0:
if pos < 0:
raise ValueError("negative seek position %r" % (pos,))
self._pos = pos
elif whence == 1:
self._pos = max(0, self._pos + pos)
elif whence == 2:
self._pos = max(0, len(self._buffer) + pos)
else:
raise ValueError("invalid whence value")
return self._pos
def tell(self):
if self.closed:
raise ValueError("tell on closed file")
return self._pos
def truncate(self, pos=None):
if self.closed:
raise ValueError("truncate on closed file")
if pos is None:
pos = self._pos
else:
try:
pos.__index__
except AttributeError:
raise TypeError("an integer is required")
if pos < 0:
raise ValueError("negative truncate position %r" % (pos,))
del self._buffer[pos:]
return pos
def readable(self):
self._checkClosed()
return True
def writable(self):
self._checkClosed()
return True
def seekable(self):
self._checkClosed()
return True
class BufferedReader(_BufferedIOMixin):
"""BufferedReader(raw[, buffer_size])
A buffer for a readable, sequential BaseRawIO object.
The constructor creates a BufferedReader for the given readable raw
stream and buffer_size. If buffer_size is omitted, DEFAULT_BUFFER_SIZE
is used.
"""
def __init__(self, raw, buffer_size=DEFAULT_BUFFER_SIZE):
"""Create a new buffered reader using the given readable raw IO object.
"""
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
self._reset_read_buf()
self._read_lock = Lock()
self._ok = True # Jython: to enable use now in a valid state
def _reset_read_buf(self):
self._read_buf = b""
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")
