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-rwxr-xr-xsrc/console/zmq/eventloop/minitornado/platform/common.py91
1 files changed, 91 insertions, 0 deletions
diff --git a/src/console/zmq/eventloop/minitornado/platform/common.py b/src/console/zmq/eventloop/minitornado/platform/common.py
new file mode 100755
index 00000000..2d75dc1e
--- /dev/null
+++ b/src/console/zmq/eventloop/minitornado/platform/common.py
@@ -0,0 +1,91 @@
+"""Lowest-common-denominator implementations of platform functionality."""
+from __future__ import absolute_import, division, print_function, with_statement
+
+import errno
+import socket
+
+from . import interface
+
+
+class Waker(interface.Waker):
+ """Create an OS independent asynchronous pipe.
+
+ For use on platforms that don't have os.pipe() (or where pipes cannot
+ be passed to select()), but do have sockets. This includes Windows
+ and Jython.
+ """
+ def __init__(self):
+ # Based on Zope async.py: http://svn.zope.org/zc.ngi/trunk/src/zc/ngi/async.py
+
+ self.writer = socket.socket()
+ # Disable buffering -- pulling the trigger sends 1 byte,
+ # and we want that sent immediately, to wake up ASAP.
+ self.writer.setsockopt(socket.IPPROTO_TCP, socket.TCP_NODELAY, 1)
+
+ count = 0
+ while 1:
+ count += 1
+ # Bind to a local port; for efficiency, let the OS pick
+ # a free port for us.
+ # Unfortunately, stress tests showed that we may not
+ # be able to connect to that port ("Address already in
+ # use") despite that the OS picked it. This appears
+ # to be a race bug in the Windows socket implementation.
+ # So we loop until a connect() succeeds (almost always
+ # on the first try). See the long thread at
+ # http://mail.zope.org/pipermail/zope/2005-July/160433.html
+ # for hideous details.
+ a = socket.socket()
+ a.bind(("127.0.0.1", 0))
+ a.listen(1)
+ connect_address = a.getsockname() # assigned (host, port) pair
+ try:
+ self.writer.connect(connect_address)
+ break # success
+ except socket.error as detail:
+ if (not hasattr(errno, 'WSAEADDRINUSE') or
+ detail[0] != errno.WSAEADDRINUSE):
+ # "Address already in use" is the only error
+ # I've seen on two WinXP Pro SP2 boxes, under
+ # Pythons 2.3.5 and 2.4.1.
+ raise
+ # (10048, 'Address already in use')
+ # assert count <= 2 # never triggered in Tim's tests
+ if count >= 10: # I've never seen it go above 2
+ a.close()
+ self.writer.close()
+ raise socket.error("Cannot bind trigger!")
+ # Close `a` and try again. Note: I originally put a short
+ # sleep() here, but it didn't appear to help or hurt.
+ a.close()
+
+ self.reader, addr = a.accept()
+ self.reader.setblocking(0)
+ self.writer.setblocking(0)
+ a.close()
+ self.reader_fd = self.reader.fileno()
+
+ def fileno(self):
+ return self.reader.fileno()
+
+ def write_fileno(self):
+ return self.writer.fileno()
+
+ def wake(self):
+ try:
+ self.writer.send(b"x")
+ except (IOError, socket.error):
+ pass
+
+ def consume(self):
+ try:
+ while True:
+ result = self.reader.recv(1024)
+ if not result:
+ break
+ except (IOError, socket.error):
+ pass
+
+ def close(self):
+ self.reader.close()
+ self.writer.close()