Only ever test for non-127.0.0.1 addresses on Windows in PostgresNode

This has been found to cause hangs where tcp usage is forced.

Alexey Kodratov

Discussion: https://postgr.es/m/82e271a9a11928337fcb5b5e57b423c0@postgrespro.ru

Backpatch to all live branches

diff --git a/src/test/perl/PostgresNode.pm b/src/test/perl/PostgresNode.pm
index 0b07f3947cb6c69dcf9de7f78384ebb4857d2639..0ed0114a99beeefb6fed7dd605b2bd719371f2c6 100644 (file)
--- a/src/test/perl/PostgresNode.pm
+++ b/src/test/perl/PostgresNode.pm
@@ -977,28 +977,25 @@ sub get_new_node
            $found = 0 if ($node->port == $port);
        }
 
-       # Check to see if anything else is listening on this TCP port.  This
-       # is *necessary* on $use_tcp (Windows) configurations.  Seek a port
-       # available for all possible listen_addresses values, for own_host
-       # nodes and so the caller can harness this port for the widest range
-       # of purposes.  The 0.0.0.0 test achieves that for post-2006 Cygwin,
-       # which automatically sets SO_EXCLUSIVEADDRUSE.  The same holds for
-       # MSYS (a Cygwin fork).  Testing 0.0.0.0 is insufficient for Windows
-       # native Perl (https://stackoverflow.com/a/14388707), so we also test
-       # individual addresses.
+       # Check to see if anything else is listening on this TCP port.
+       # Seek a port available for all possible listen_addresses values,
+       # so callers can harness this port for the widest range of purposes.
+       # The 0.0.0.0 test achieves that for MSYS, which automatically sets
+       # SO_EXCLUSIVEADDRUSE.  Testing 0.0.0.0 is insufficient for Windows
+       # native Perl (https://stackoverflow.com/a/14388707), so we also
+       # have to test individual addresses.  Doing that for 127.0.0/24
+       # addresses other than 127.0.0.1 might fail with EADDRNOTAVAIL on
+       # non-Linux, non-Windows kernels.
        #
-       # This seems like a good idea on Unixen as well, even though we don't
-       # ask the postmaster to open a TCP port on Unix.  On Non-Linux,
-       # non-Windows kernels, binding to 127.0.0.1/24 addresses other than
-       # 127.0.0.1 might fail with EADDRNOTAVAIL.  Binding to 0.0.0.0 is
-       # unnecessary on non-Windows systems.
-       #
-       # XXX A port available now may become unavailable by the time we start
-       # the postmaster.
+       # Thus, 0.0.0.0 and individual 127.0.0/24 addresses are tested
+       # only on Windows and only when TCP usage is requested.
        if ($found == 1)
        {
            foreach my $addr (qw(127.0.0.1),
-               $use_tcp ? qw(127.0.0.2 127.0.0.3 0.0.0.0) : ())
+               $use_tcp ? qw(127.0.0.2 127.0.0.3 0.0.0.0) : ())
+               $use_tcp && $TestLib::windows_os
+               ? qw(127.0.0.2 127.0.0.3 0.0.0.0)
+               : ())
            {
                can_bind($addr, $port) or $found = 0;
            }