TonyC noticed that the dynamic channel listing was broken. It didn't

list anything until the bot side was kicked and invited back, and then
it only listed the channel it was re-invited to.  This patch reworks
the channel management functions in Util::Data and also disambiguates
lc() calls in Client::IRC.

Actually, it seems that a previous patch removed irc_join.  We put it
back as well.

Client/IRC.pm

@@ -409,12 +409,18 @@ foreach my $server (get_names_by_type('irc')) {
           delete $heap->{users}{$where}{$nick};
         },
 
+        irc_join => sub {
+          my ($kernel, $who, $where) = @_[KERNEL, ARG0, ARG1];
+          my ($nick) = $who =~ /^([^!]+)/;
+          add_channel($where) if lc($nick) eq lc($conf{nick});
+        },
+
         # who reply
         irc_352 => sub {
           my ($kernel, $heap, $what) = @_[KERNEL, HEAP, ARG1];
 
           my @reply = split " ", $what, 8;
-          @{$heap->{users}{$reply[0]}{$reply[4]}}{qw(ident host mode real)} = 
+          @{$heap->{users}{$reply[0]}{$reply[4]}}{qw(ident host mode real)} =
             ($reply[1], $reply[2], $reply[5], $reply[7]);
         },
 

Util/Data.pm

@@ -30,7 +30,7 @@ sub PASTE_HOST    () { 5 }
 my $id_sequence = 0;
 my %paste_cache;
 my %ignores; # $ignores{$ircnet}{lc $channel} = [ mask, mask, ... ];
-my @channels;
+my %channels;
 
 # return a list of all paste ids
 
@@ -207,29 +207,25 @@ sub clear_channel_ignores {
 # Channels we're on
 
 sub channels {
-  return @channels;
+  return sort keys %channels;
 }
 
 sub clear_channels {
-  @channels = ();
-  return if @channels;  # Should never happen
+  %channels = ();
+  return if keys %channels;  # Should never happen
   return 1;
 }
 
 sub add_channel {
   my ($channel) = @_;
-  $channel = lc $channel;
-  return if grep $_ eq $channel, @channels;
-  return push @channels, $channel;
+  $channel = lc($channel);
+  $channels{$channel} = 1;
 }
 
 sub remove_channel {
   my ($channel) = @_;
-  $channel = lc $channel;
-  my $found = 0;
-  @channels = grep { $_ eq $channel ? do { $found++; 0; } : 1 } @channels;
-  return if not $found;
-  return $found;
+  $channel = lc($channel);
+  delete $channels{$channel};  # returns automatically
 }
 
 # Init stuff