blob: 833ee3b4c95db0aa0eeafa9dcaeb03d788004379 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
|
# Copyright 1999-2010 Gentoo Foundation
# Distributed under the terms of the GNU General Public License v2
import array
from _emerge.AsynchronousTask import AsynchronousTask
from _emerge.PollConstants import PollConstants
class AbstractPollTask(AsynchronousTask):
__slots__ = ("scheduler",) + \
("_registered",)
_bufsize = 4096
_exceptional_events = PollConstants.POLLERR | PollConstants.POLLNVAL
_registered_events = PollConstants.POLLIN | PollConstants.POLLHUP | \
_exceptional_events
def _read_buf(self, f, event):
"""
| POLLIN | RETURN
| BIT | VALUE
| ---------------------------------------------------
| 1 | Read self._bufsize into an instance of
| | array.array('B') and return it, ignoring
| | EOFError and IOError. An empty array
| | indicates EOF.
| ---------------------------------------------------
| 0 | None
"""
buf = None
if event & PollConstants.POLLIN:
buf = array.array('B')
try:
buf.fromfile(f, self._bufsize)
except (EOFError, IOError):
pass
return buf
def _unregister(self):
raise NotImplementedError(self)
def _unregister_if_appropriate(self, event):
if self._registered:
if event & self._exceptional_events:
self._unregister()
self.cancel()
elif event & PollConstants.POLLHUP:
self._unregister()
self.wait()
|
