eventlet/eventlet/hubs/selects.py

   1 import errno
   2 import sys
   3 from eventlet import patcher
   4 from eventlet.support import get_errno, clear_sys_exc_info
   5 select = patcher.original('select')
   6 time = patcher.original('time')
   7
   8 from eventlet.hubs.hub import BaseHub, READ, WRITE, noop
   9
  10 try:
  11     BAD_SOCK = set((errno.EBADF, errno.WSAENOTSOCK))
  12 except AttributeError:
  13     BAD_SOCK = set((errno.EBADF,))
  14
  15
  16 class Hub(BaseHub):
  17     def _remove_bad_fds(self):
  18         """ Iterate through fds, removing the ones that are bad per the
  19         operating system.
  20         """
  21         all_fds = list(self.listeners[READ]) + list(self.listeners[WRITE])
  22         for fd in all_fds:
  23             try:
  24                 select.select([fd], [], [], 0)
  25             except select.error as e:
  26                 if get_errno(e) in BAD_SOCK:
  27                     self.remove_descriptor(fd)
  28
  29     def wait(self, seconds=None):
  30         readers = self.listeners[READ]
  31         writers = self.listeners[WRITE]
  32         if not readers and not writers:
  33             if seconds:
  34                 time.sleep(seconds)
  35             return
  36         all_fds = list(readers) + list(writers)
  37         try:
  38             r, w, er = select.select(readers.keys(), writers.keys(), all_fds, seconds)
  39         except select.error as e:
  40             if get_errno(e) == errno.EINTR:
  41                 return
  42             elif get_errno(e) in BAD_SOCK:
  43                 self._remove_bad_fds()
  44                 return
  45             else:
  46                 raise
  47
  48         for fileno in er:
  49             readers.get(fileno, noop).cb(fileno)
  50             writers.get(fileno, noop).cb(fileno)
  51
  52         for listeners, events in ((readers, r), (writers, w)):
  53             for fileno in events:
  54                 try:
  55                     listeners.get(fileno, noop).cb(fileno)
  56                 except self.SYSTEM_EXCEPTIONS:
  57                     raise
  58                 except:
  59                     self.squelch_exception(fileno, sys.exc_info())
  60                     clear_sys_exc_info()