bpo-31922: Do not connect UDP sockets when broadcast is allowed (GH-423)
*Moved from python/asyncio#493.*
This PR fixes issue python/asyncio#480, as explained in [this comment](https://github.com/python/asyncio/issues/480#issuecomment-278703828).
The `_SelectorDatagramTransport.sendto` method has to be modified ~~so `_sock.sendto` is used in all cases (because it is tricky to reliably tell if the socket is connected or not). Could that be an issue for connected sockets?~~ *EDIT* ... so `_sock.send` is used only if `_sock` is connected.
It also protects `socket.getsockname` against `OSError` in `_SelectorTransport`. This might happen on Windows if the socket is not connected (e.g. for UDP broadcasting).
https://bugs.python.org/issue31922
diff --git a/Lib/asyncio/base_events.py b/Lib/asyncio/base_events.py
index c58906f..9613ac2 100644
--- a/Lib/asyncio/base_events.py
+++ b/Lib/asyncio/base_events.py
@@ -1306,7 +1306,8 @@
if local_addr:
sock.bind(local_address)
if remote_addr:
- await self.sock_connect(sock, remote_address)
+ if not allow_broadcast:
+ await self.sock_connect(sock, remote_address)
r_addr = remote_address
except OSError as exc:
if sock is not None: