zeroconf: do not crash if socket being read is closed by another thread
In zeroconf/__init__.py, there is:
server = Zeroconf.Zeroconf(ip)
l = listener()
Zeroconf.ServiceBrowser(server, "_hg._tcp.local.", l)
time.sleep(1)
server.close()
`server.close()` closes the underlying socket while the `ServiceBrowser` may
still have a background thread reading the socket. There could be a race
condition where the reading thread reads the closed socket, resulting in
EBADF crash. This patch catches the exception.
This makes test-paths.t pass with chg.
Differential Revision: https://phab.mercurial-scm.org/D919
--- a/hgext/zeroconf/Zeroconf.py Mon Oct 02 19:31:33 2017 -0700
+++ b/hgext/zeroconf/Zeroconf.py Mon Oct 02 20:23:25 2017 -0700
@@ -80,6 +80,7 @@
__email__ = "paul at scott dash murphy dot com"
__version__ = "0.12"
+import errno
import itertools
import select
import socket
@@ -937,7 +938,16 @@
self.zeroconf.engine.addReader(self, self.zeroconf.socket)
def handle_read(self):
- data, (addr, port) = self.zeroconf.socket.recvfrom(_MAX_MSG_ABSOLUTE)
+ data = addr = port = None
+ sock = self.zeroconf.socket
+ try:
+ data, (addr, port) = sock.recvfrom(_MAX_MSG_ABSOLUTE)
+ except socket.error as e:
+ if e.errno == errno.EBADF:
+ # some other thread may close the socket
+ return
+ else:
+ raise
self.data = data
msg = DNSIncoming(data)
if msg.isQuery():