daemon: make Socket6 optional, note about Net::Socket::IP

It looks like Net::Socket::IP comes with Perl 5.20 and
later; so we won't have to hassle users with another
package to install.

1 files changed, 16 insertions, 3 deletions

diff --git a/lib/PublicInbox/Daemon.pm b/lib/PublicInbox/Daemon.pm
index 6d2ae81b..6aa4a194 100644
--- a/lib/PublicInbox/Daemon.pm
+++ b/lib/PublicInbox/Daemon.pm
@@ -234,6 +234,21 @@ sub sockname ($) {
         "$host:$port";
 }
 
+sub unpack_ipv6 ($) {
+        my ($addr) = @_;
+
+        # TODO: support IO::Socket::IP which comes with Perl 5.24
+        # (perl-modules-5.24 in Debian)
+
+        # SpamAssassin and Net::Server use Socket6, so it may be installed
+        # on our system, already:
+        eval { require Socket6 } or return ('???-Socket6-missing', 0);
+
+        my ($port, $host) = Socket6::unpack_sockaddr_in6($addr);
+        $host = Socket6::inet_ntop(Socket6::AF_INET6(), $host);
+        ($host, $port);
+}
+
 sub host_with_port ($) {
         my ($addr) = @_;
         my ($port, $host);
@@ -241,9 +256,7 @@ sub host_with_port ($) {
         # this eval will die on Unix sockets:
         eval {
                 if (length($addr) >= 28) {
-                        require Socket6;
-                        ($port, $host) = Socket6::unpack_sockaddr_in6($addr);
-                        $host = Socket6::inet_ntop(Socket6::AF_INET6(), $host);
+                        ($host, $port) = unpack_ipv6($addr);
                         $host = "[$host]";
                 } else {
                         ($port, $host) = Socket::sockaddr_in($addr);