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-rw-r--r--python/gevent/select.py286
1 files changed, 0 insertions, 286 deletions
diff --git a/python/gevent/select.py b/python/gevent/select.py
deleted file mode 100644
index a4c182c..0000000
--- a/python/gevent/select.py
+++ /dev/null
@@ -1,286 +0,0 @@
-# Copyright (c) 2009-2011 Denis Bilenko. See LICENSE for details.
-"""
-Waiting for I/O completion.
-"""
-from __future__ import absolute_import, division, print_function
-
-import sys
-
-from gevent.event import Event
-from gevent.hub import _get_hub_noargs as get_hub
-from gevent.hub import sleep as _g_sleep
-from gevent._compat import integer_types
-from gevent._compat import iteritems
-from gevent._util import copy_globals
-from gevent._util import _NONE
-
-from errno import EINTR
-from select import select as _real_original_select
-if sys.platform.startswith('win32'):
- def _original_select(r, w, x, t):
- # windows cant handle three empty lists, but we've always
- # accepted that
- if not r and not w and not x:
- return ((), (), ())
- return _real_original_select(r, w, x, t)
-else:
- _original_select = _real_original_select
-
-
-try:
- from select import poll as original_poll
- from select import POLLIN, POLLOUT, POLLNVAL
- __implements__ = ['select', 'poll']
-except ImportError:
- original_poll = None
- __implements__ = ['select']
-
-__all__ = ['error'] + __implements__
-
-import select as __select__
-
-error = __select__.error
-
-__imports__ = copy_globals(__select__, globals(),
- names_to_ignore=__all__,
- dunder_names_to_keep=())
-
-_EV_READ = 1
-_EV_WRITE = 2
-
-def get_fileno(obj):
- try:
- fileno_f = obj.fileno
- except AttributeError:
- if not isinstance(obj, integer_types):
- raise TypeError('argument must be an int, or have a fileno() method: %r' % (obj,))
- return obj
- else:
- return fileno_f()
-
-
-class SelectResult(object):
- __slots__ = ('read', 'write', 'event')
-
- def __init__(self):
- self.read = []
- self.write = []
- self.event = Event()
-
- def add_read(self, socket):
- self.read.append(socket)
- self.event.set()
-
- add_read.event = _EV_READ
-
- def add_write(self, socket):
- self.write.append(socket)
- self.event.set()
-
- add_write.event = _EV_WRITE
-
- def __add_watchers(self, watchers, fdlist, callback, io, pri):
- for fd in fdlist:
- watcher = io(get_fileno(fd), callback.event)
- watcher.priority = pri
- watchers.append(watcher)
- watcher.start(callback, fd)
-
- def _make_watchers(self, watchers, rlist, wlist):
- loop = get_hub().loop
- io = loop.io
- MAXPRI = loop.MAXPRI
-
- try:
- self.__add_watchers(watchers, rlist, self.add_read, io, MAXPRI)
- self.__add_watchers(watchers, wlist, self.add_write, io, MAXPRI)
- except IOError as ex:
- raise error(*ex.args)
-
- def _closeall(self, watchers):
- for watcher in watchers:
- watcher.stop()
- watcher.close()
- del watchers[:]
-
- def select(self, rlist, wlist, timeout):
- watchers = []
- try:
- self._make_watchers(watchers, rlist, wlist)
- self.event.wait(timeout=timeout)
- return self.read, self.write, []
- finally:
- self._closeall(watchers)
-
-
-def select(rlist, wlist, xlist, timeout=None): # pylint:disable=unused-argument
- """An implementation of :meth:`select.select` that blocks only the current greenlet.
-
- .. caution:: *xlist* is ignored.
-
- .. versionchanged:: 1.2a1
- Raise a :exc:`ValueError` if timeout is negative. This matches Python 3's
- behaviour (Python 2 would raise a ``select.error``). Previously gevent had
- undefined behaviour.
- .. versionchanged:: 1.2a1
- Raise an exception if any of the file descriptors are invalid.
- """
- if timeout is not None and timeout < 0:
- # Raise an error like the real implementation; which error
- # depends on the version. Python 3, where select.error is OSError,
- # raises a ValueError (which makes sense). Older pythons raise
- # the error from the select syscall...but we don't actually get there.
- # We choose to just raise the ValueError as it makes more sense and is
- # forward compatible
- raise ValueError("timeout must be non-negative")
-
- # First, do a poll with the original select system call. This
- # is the most efficient way to check to see if any of the file descriptors
- # have previously been closed and raise the correct corresponding exception.
- # (Because libev tends to just return them as ready...)
- # We accept the *xlist* here even though we can't below because this is all about
- # error handling.
- sel_results = ((), (), ())
- try:
- sel_results = _original_select(rlist, wlist, xlist, 0)
- except error as e:
- enumber = getattr(e, 'errno', None) or e.args[0]
- if enumber != EINTR:
- # Ignore interrupted syscalls
- raise
-
- if sel_results[0] or sel_results[1] or sel_results[2] or (timeout is not None and timeout == 0):
- # If we actually had stuff ready, go ahead and return it. No need
- # to go through the trouble of doing our own stuff.
-
- # Likewise, if the timeout is 0, we already did a 0 timeout
- # select and we don't need to do it again. Note that in libuv,
- # zero duration timers may be called immediately, without
- # cycling the event loop at all. 2.7/test_telnetlib.py "hangs"
- # calling zero-duration timers if we go to the loop here.
-
- # However, because this is typically a place where scheduling switches
- # can occur, we need to make sure that's still the case; otherwise a single
- # consumer could monopolize the thread. (shows up in test_ftplib.)
- _g_sleep()
- return sel_results
-
- result = SelectResult()
- return result.select(rlist, wlist, timeout)
-
-
-if original_poll is not None:
- class PollResult(object):
- __slots__ = ('events', 'event')
-
- def __init__(self):
- self.events = set()
- self.event = Event()
-
- def add_event(self, events, fd):
- if events < 0:
- result_flags = POLLNVAL
- else:
- result_flags = 0
- if events & _EV_READ:
- result_flags = POLLIN
- if events & _EV_WRITE:
- result_flags |= POLLOUT
-
- self.events.add((fd, result_flags))
- self.event.set()
-
- class poll(object):
- """
- An implementation of :class:`select.poll` that blocks only the current greenlet.
-
- .. caution:: ``POLLPRI`` data is not supported.
-
- .. versionadded:: 1.1b1
- """
- def __init__(self):
- # {int -> flags}
- # We can't keep watcher objects in here because people commonly
- # just drop the poll object when they're done, without calling
- # unregister(). dnspython does this.
- self.fds = {}
- self.loop = get_hub().loop
-
- def register(self, fd, eventmask=_NONE):
- if eventmask is _NONE:
- flags = _EV_READ | _EV_WRITE
- else:
- flags = 0
- if eventmask & POLLIN:
- flags = _EV_READ
- if eventmask & POLLOUT:
- flags |= _EV_WRITE
- # If they ask for POLLPRI, we can't support
- # that. Should we raise an error?
-
- fileno = get_fileno(fd)
- self.fds[fileno] = flags
-
- def modify(self, fd, eventmask):
- self.register(fd, eventmask)
-
- def poll(self, timeout=None):
- """
- poll the registered fds.
-
- .. versionchanged:: 1.2a1
- File descriptors that are closed are reported with POLLNVAL.
-
- .. versionchanged:: 1.3a2
- Under libuv, interpret *timeout* values less than 0 the same as *None*,
- i.e., block. This was always the case with libev.
- """
- result = PollResult()
- watchers = []
- io = self.loop.io
- MAXPRI = self.loop.MAXPRI
- try:
- for fd, flags in iteritems(self.fds):
- watcher = io(fd, flags)
- watchers.append(watcher)
- watcher.priority = MAXPRI
- watcher.start(result.add_event, fd, pass_events=True)
- if timeout is not None:
- if timeout < 0:
- # The docs for python say that an omitted timeout,
- # a negative timeout and a timeout of None are all
- # supposed to block forever. Many, but not all
- # OS's accept any negative number to mean that. Some
- # OS's raise errors for anything negative but not -1.
- # Python 3.7 changes to always pass exactly -1 in that
- # case from selectors.
-
- # Our Timeout class currently does not have a defined behaviour
- # for negative values. On libuv, it uses a check watcher and effectively
- # doesn't block. On libev, it seems to block. In either case, we
- # *want* to block, so turn this into the sure fire block request.
- timeout = None
- elif timeout:
- # The docs for poll.poll say timeout is in
- # milliseconds. Our result objects work in
- # seconds, so this should be *=, shouldn't it?
- timeout /= 1000.0
- result.event.wait(timeout=timeout)
- return list(result.events)
- finally:
- for awatcher in watchers:
- awatcher.stop()
- awatcher.close()
-
- def unregister(self, fd):
- """
- Unregister the *fd*.
-
- .. versionchanged:: 1.2a1
- Raise a `KeyError` if *fd* was not registered, like the standard
- library. Previously gevent did nothing.
- """
- fileno = get_fileno(fd)
- del self.fds[fileno]
-
-del original_poll
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