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 b32223f716433213520926358b58908150df5e75..8394c57d3f872d1332a399062f2f5acfacb526aa 100644 (file)
--- a/src/test/perl/PostgresNode.pm
+++ b/src/test/perl/PostgresNode.pm
@@ -1332,19 +1332,22 @@ sub get_free_port
                # 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 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.
+               # 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.
                #
-               # On non-Linux, non-Windows kernels, binding to 127.0.0/24 addresses
-               # other than 127.0.0.1 might fail with EADDRNOTAVAIL.  Binding to
-               # 0.0.0.0 is unnecessary on non-Windows systems.
+               # 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 && $TestLib::windows_os
+               ? qw(127.0.0.2 127.0.0.3 0.0.0.0)
+               : ())
                        {
                                if (!can_bind($addr, $port))
                                {