| Subject: | [patch] erroneous arguments given to the packet handler |
Hello,
While cleaning the patch and writing the tests for #84749, I discovered that the way arguments are given to the packet handler is quite wrong: because the count argument of pcap_dispatch() is -1, it actually processes as many packets as it can, meaning that several pairs of ($header,$packet) are pushed in @pending. As a result, when the packet handler is called back, it can received much more than the two documented arguments (and even more than the three arguments, given that the internal AnyEvent::IO object is also passed).
With the samples from #84749, which consists of 10 pings to www.ietf.org, the packet handler is called once with 41 arguments.
The consequence is that, in such a case, the handler will miss many packets because it does not expect to process more than one packet at a time.
Attached is a patch that correct this. However, the packet handler in t/10_setup_pcap.t is called a third time for a reason I can't understand.
Regards,
Sébastien Aperghis-Tramoni
--
Close the world, txEn eht nepO.
| Subject: | packet-handler-args.diff |
commit f5f72886415ae97bd9b7ed59440443287787c5af
Author: Sébastien Aperghis-Tramoni <sebastien.aperghis-tramoni@diabolocom.com>
Date: Fri Apr 19 20:09:09 2013 +0200
make sure the packet handler is only called with the documented arguments, and that no packet is missed
diff --git a/lib/AnyEvent/Pcap.pm b/lib/AnyEvent/Pcap.pm
index e394019..5e640fb 100644
--- a/lib/AnyEvent/Pcap.pm
+++ b/lib/AnyEvent/Pcap.pm
@@ -79,6 +79,7 @@ sub run {
my $self = shift;
my $pcap = $self->_setup_pcap();
+ my $empty = { len => 0, caplen => 0, tv_sec => 0, tv_usec => 0 };
my $packet_handler = $self->packet_handler || sub {
$self->packet_handler( sub { } );
@@ -90,17 +91,17 @@ sub run {
fh => $self->fd,
poll => 'r',
cb => sub {
- my @pending;
+ my @args;
Net::Pcap::dispatch(
- $pcap, -1,
+ $pcap, 1,
sub {
my $header = $_[1];
my $packet = $_[2];
push @{ $_[0] }, ( $header, $packet );
},
- \@pending
+ \@args
);
- $packet_handler->( @pending, $io );
+ $packet_handler->( $args[0]||$empty, $args[1]||"", $io );
}
);
}