check socket creation errors against PGINVALID_SOCKET

Bruce Momjian <bruce@momjian.us>

Commit: bed499ed1d94f05195c63387d4629644e0df4149
Author: Bruce Momjian <bruce@momjian.us>
Date: 2014-04-16T14:45:48Z
Releases: 9.1.14
check socket creation errors against PGINVALID_SOCKET

Previously, in some places, socket creation errors were checked for
negative values, which is not true for Windows because sockets are
unsigned.  This masked socket creation errors on Windows.

Backpatch through 9.0.  8.4 doesn't have the infrastructure to fix this.

Files