MT#62272 AutoTest: introduce rcv_maybe()

A dummy function to ignore the fact
whether RTP packet(s) received or not.

Useful in a combination with rcv_no().

Change-Id: Iaeea881e0a3590808dcc681495095178cb470b94
(cherry picked from commit 675c1b3bad)
(cherry picked from commit 4a90f1d6fa)

perl/NGCP/Rtpengine/AutoTest.pm

@@ -20,7 +20,7 @@ our $launch_cb;
 BEGIN {
 	require Exporter;
 	@ISA = qw(Exporter);
-	our @EXPORT = qw(autotest_start new_call offer answer ft tt cid snd srtp_snd rtp rcv srtp_rcv rcv_no
+	our @EXPORT = qw(autotest_start new_call offer answer ft tt cid snd srtp_snd rtp rcv srtp_rcv rcv_no rcv_maybe
 		srtp_dec escape rtpm rtpmre reverse_tags new_ft new_tt crlf sdp_split rtpe_req offer_answer
 		autotest_init subscribe_request subscribe_answer publish use_json);
 };
@@ -247,6 +247,13 @@ sub rcv_no {
 	my $addr = $sock->recv($p, 65535, &MSG_DONTWAIT);
 	ok(! defined $addr, "no packet received");
 }
+sub rcv_maybe {
+	my ($sock) = @_;
+	Time::HiRes::sleep(0.1);
+	my $p = '';
+	my $addr = $sock->recv($p, 65535, &MSG_DONTWAIT);
+	ok(1, "whatever packet received or not");
+}
 sub srtp_rcv {
 	my ($sock, $port, $match, $srtp_ctx) = @_;
 	return rcv($sock, $port, $match, \&srtp_dec, $srtp_ctx);