django-downloadview/django_downloadview/io.py

65 lines
1.7 KiB
Python

# -*- coding: utf-8 -*-
"""Low-level IO operations, for use with file wrappers."""
from __future__ import absolute_import
import io
class StringIteratorIO(io.TextIOBase):
"""A dynamically generated StringIO-like object.
Original code by Matt Joiner <anacrolix@gmail.com> from:
* http://stackoverflow.com/questions/12593576/
* https://gist.github.com/anacrolix/3788413
"""
def __init__(self, iterator):
self._iter = iterator
self._left = ''
def readable(self):
return True
def _read1(self, n=None):
while not self._left:
try:
self._left = next(self._iter)
except StopIteration:
break
ret = self._left[:n]
self._left = self._left[len(ret):]
return ret
def read(self, n=None):
l = []
if n is None or n < 0:
while True:
m = self._read1()
if not m:
break
l.append(m)
else:
while n > 0:
m = self._read1(n)
if not m:
break
n -= len(m)
l.append(m)
return ''.join(l)
def readline(self):
l = []
while True:
i = self._left.find('\n')
if i == -1:
l.append(self._left)
try:
self._left = next(self._iter)
except StopIteration:
self._left = ''
break
else:
l.append(self._left[:i + 1])
self._left = self._left[i + 1:]
break
return ''.join(l)