tor/changes/bug21540

  o Minor bugfixes (windows, relay):
    - Resolve "Failure from drain_fd: No error" warnings on Windows
      relays. Fixes bug 21540; bugfix on 0.2.6.3-alpha.
Correctly handle fd-drain errors on windows workqueues Windows doesn't let you check the socket error for a socket with WSAGetLastError() and getsockopt(SO_ERROR). But getsockopt(SO_ERROR) clears the error on the socket, so you can't call it more than once per error. When we introduced recv_ni to help drain alert sockets, back in 0.2.6.3-alpha, we had the failure path for recv_ni call getsockopt() twice, though: once to check for EINTR and one to check for EAGAIN. Of course, we never got the eagain, so we treated it as an error, and warned about: "No error". The fix here is to have these functions return -errno on failure. Fixes bug 21540; bugfix on 0.2.6.3-alpha. 2017-03-15 16:53:01 +01:00			`o Minor bugfixes (windows, relay):`
			`- Resolve "Failure from drain_fd: No error" warnings on Windows`
			`relays. Fixes bug 21540; bugfix on 0.2.6.3-alpha.`