NAME
IRC::Utils - Common utilities for IRC-related tasks
SYNOPSIS
use strict;
use warnings;
use IRC::Utils ':ALL';
my $nickname = '^Lame|BOT[moo]';
my $uppercase_nick = uc_irc($nickname);
my $lowercase_nick = lc_irc($nickname);
print "They're equivalent\n" if eq_irc($uppercase_nick, $lowercase_nick);
my $mode_line = 'ov+b-i Bob sue stalin*!*@*';
my $hashref = parse_mode_line($mode_line);
my $banmask = 'stalin*';
my $full_banmask = normalize_mask($banmask);
if (matches_mask($full_banmask, 'stalin!joe@kremlin.ru')) {
print "EEK!";
}
my $decoded = irc_decode($raw_irc_message);
print $decoded, "\n";
if (has_color($message)) {
print 'COLOR CODE ALERT!\n";
}
my $results_hashref = matches_mask_array(\@masks, \@items_to_match_against);
my $nick = parse_user('stalin!joe@kremlin.ru');
my ($nick, $user, $host) = parse_user('stalin!joe@kremlin.ru');
DESCRIPTION
The functions in this module take care of many of the tasks you are
faced with when working with IRC. Mode lines, ban masks, message
encoding and formatting, etc.
FUNCTIONS
"uc_irc"
Takes one mandatory parameter, a string to convert to IRC uppercase, and
one optional parameter, the casemapping of the ircd (which can be
'rfc1459', 'strict-rfc1459' or 'ascii'. Default is 'rfc1459'). Returns
the IRC uppercase equivalent of the passed string.
"lc_irc"
Takes one mandatory parameter, a string to convert to IRC lowercase, and
one optional parameter, the casemapping of the ircd (which can be
'rfc1459', 'strict-rfc1459' or 'ascii'. Default is 'rfc1459'). Returns
the IRC lowercase equivalent of the passed string.
"eq_irc"
Takes two mandatory parameters, IRC strings (channels or nicknames) to
compare. A third, optional parameter specifies the casemapping. Returns
true if the two strings are equivalent, false otherwise
# long version
lc_irc($one, $map) eq lc_irc($two, $map)
# short version
eq_irc($one, $two, $map)
"parse_mode_line"
Takes a list representing an IRC mode line. Returns a hashref.
Optionally you can also supply an arrayref and a hashref to specify
valid channel modes (default: "[qw(beI k l imnpstaqr)]") and status
modes (default: "{o => '@', h => '%', v => '+'}"), respectively.
If the modeline couldn't be parsed the hashref will be empty. On success
the following keys will be available in the hashref:
'modes', an arrayref of normalised modes;
'args', an arrayref of applicable arguments to the modes;
Example:
my $hashref = parse_mode_line( 'ov+b-i', 'Bob', 'sue', 'stalin*!*@*' );
# $hashref will be:
{
modes => [ '+o', '+v', '+b', '-i' ],
args => [ 'Bob', 'sue', 'stalin*!*@*' ],
}
"normalize_mask"
Takes one parameter, a string representing an IRC mask. Returns a
normalised full mask.
Example:
$fullbanmask = normalize_mask( 'stalin*' );
# $fullbanmask will be: 'stalin*!*@*';
"matches_mask"
Takes two parameters, a string representing an IRC mask and something to
match against the IRC mask, such as a nick!user@hostname string. Returns
a true value if they match, a false value otherwise. Optionally, one may
pass the casemapping (see "uc_irc"), as this function uses "uc_irc"
internally.
"matches_mask_array"
Takes two array references, the first being a list of strings
representing IRC masks, the second a list of somethings to test against
the masks. Returns an empty hashref if there are no matches. Otherwise,
the keys will be the masks matched, each value being an arrayref of the
strings that matched it. Optionally, one may pass the casemapping (see
"uc_irc"), as this function uses "uc_irc" internally.
"unparse_mode_line"
Takes one argument, a string representing a number of mode changes.
Returns a condensed version of the changes.
my $mode_line = unparse_mode_line('+o+o+o-v+v');
$mode_line is now '+ooo-v+v'
"gen_mode_change"
Takes two arguments, strings representing a set of IRC user modes before
and after a change. Returns a string representing what changed.
my $mode_change = gen_mode_change('abcde', 'befmZ');
$mode_change is now '-acd+fmZ'
"parse_user"
Takes one parameter, a string representing a user in the form
nick!user@hostname. In a scalar context it returns just the nickname. In
a list context it returns a list consisting of the nick, user and
hostname, respectively.
"is_valid_chan_name"
Takes one argument, a channel name to validate. Returns true or false if
the channel name is valid or not. You can supply a second argument, an
array of characters of allowed channel prefixes. Defaults to "['#',
'&']".
"is_valid_nick_name"
Takes one argument, a nickname to validate. Returns true or false if the
nickname is valid or not.
"numeric_to_name"
Takes an IRC server numerical reply code (e.g. '001') as an argument,
and returns the corresponding name (e.g. 'RPL_WELCOME').
"name_to_numeric"
Takes an IRC server reply name (e.g. 'RPL_WELCOME') as an argument, and
returns the corresponding numerical code (e.g. '001').
"has_color"
Takes one parameter, a string of IRC text. Returns true if it contains
any IRC color codes, false otherwise. Useful if you want your bot to
kick users for (ab)using colors. :)
"has_formatting"
Takes one parameter, a string of IRC text. Returns true if it contains
any IRC formatting codes, false otherwise.
"strip_color"
Takes one parameter, a string of IRC text. Returns the string stripped
of all IRC color codes.
"strip_formatting"
Takes one parameter, a string of IRC text. Returns the string stripped
of all IRC formatting codes.
"decode_irc"
This function takes a byte string (i.e. an unmodified IRC message) and
returns a text string. Since the source encoding might have been UTF-8,
you should store it with UTF-8 or some other Unicode encoding in your
file/database/whatever to be safe. For a more detailed discussion, see
"ENCODING".
use IRC::Utils qw(decode_irc);
sub message_handler {
my ($nick, $channel, $message) = @_;
# not wise, $message is a byte string of unkown encoding
print $message, "\n";
$message = decode_irc($what);
# good, $message is a text string
print $message, "\n";
}
CONSTANTS
Use the following constants to add formatting and mIRC color codes to
IRC messages.
Normal text:
NORMAL
Formatting:
BOLD
UNDERLINE
REVERSE
ITALIC
FIXED
Colors:
WHITE
BLACK
BLUE
GREEN
RED
BROWN
PURPLE
ORANGE
YELLOW
LIGHT_GREEN
TEAL
LIGHT_CYAN
LIGHT_BLUE
PINK
GREY
LIGHT_GREY
Individual non-color formatting codes can be cancelled with their
corresponding constant, but you can also cancel all of them at once with
"NORMAL". To cancel the effect of color codes, you must use "NORMAL".
which of course has the side effect of cancelling all other formatting
codes as well.
$msg = 'This word is '.YELLOW.'yellow'.NORMAL.' while this word is'.BOLD.'bold'.BOLD;
$msg = UNDERLINE.BOLD.'This sentence is both underlined and bold.'.NORMAL;
ENCODING
Messages
The only encoding requirement the IRC protocol places on its messages is
that they be 8-bits and ASCII-compatible. This has resulted in most of
the Western world settling on ASCII-compatible Latin-1 (usually
Microsoft's CP1252, a Latin-1 variant) as a convention. Recently,
popular IRC clients (mIRC, xchat, certain irssi configurations) have
begun sending a mixture of CP1252 and UTF-8 over the wire to allow more
characters without breaking backward compatibility (too much). They send
CP1252 encoded messages if the characters fit within that encoding,
otherwise falling back to UTF-8, and likewise autodetecting the encoding
(UTF-8 or CP1252) of incoming messages. Since writing text with mixed
encoding to a file, terminal, or database is not a good idea, you need a
way to decode messages from IRC. "decode_irc" will do that.
Channel names
The matter is complicated further by the fact that some servers allow
non-ASCII characters in channel names. IRC modules generally don't
explicitly encode or decode any IRC traffic, but they do have to
concatenate parts of a message (e.g. a channel name and a message)
before sending it over the wire. So when you do something like
"privmsg($channel, 'æði')", where $channel is the unmodified channel
name (a byte string) you got from an earlier IRC message, the channel
name will get double-encoded when concatenated with your message (a
non-ASCII text string) if the channel name contains non-ASCII bytes.
To prevent this, you can't simply decode the channel name and then use
it. '#æði' in CP1252 is not the same channel as '#æði' in UTF-8, since
they are encoded as different sequences of bytes, and the IRC server
only cares about the byte representation. Therefore, when using a
channel name you got from the server (e.g. when replying to message),
you should use the original byte string (before it has been decoded with
"decode_irc"), and encode any other parameters (with "encode_utf8") so
that your message will be concatenated correctly. At some point, you'll
probably want to print the channel name, write it to a log file or use
it in a filename, so you'll eventually have to decode it, at which point
the UTF-8 "#æði" and CP1252 "#æði" will have to be considered
equivalent.
use Encode qw(encode_utf8 encode);
sub message_handler {
# these three are all byte strings
my ($nick, $channel, $message) = @_;
# bad: if $channel has any non-ASCII bytes, they will get double-encoded
privmsg($channel, 'æði');
# bad: if $message has any non-ASCII bytes, they will get double-encoded
privmsg('#æði', $message);
# good: both are byte strings already, so they will concatenate correctly
privmsg($channel, $message);
# good: both are text strings (Latin1 as per Perl's default), so
# they'll be concatenated correctly
privmsg('#æði', 'æði');
# good: similar to the last one, except now they're using UTF-8, which
# means that the channel is actually not the same as above
use utf8;
privmsg('#æði', 'æði');
# good: $channel and $msg_bytes are both byte strings
my $msg_bytes = encode_utf8('æði');
privmsg($channel, $msg_bytes);
# good: $chan_bytes and $message are both byte strings
# here we're sending a message to the utf8-encoded #æði
my $utf8_bytes = encode_utf8('#æði');
privmsg($utf8_bytes, $message);
# good: $chan_bytes and $message are both byte strings
# here we're sending a message to the cp1252-encoded #æði
my $cp1252_bytes = encode('cp1252', '#æði');
privmsg($cp1252_bytes, $message);
# bad: $channel is in an undetermined encoding
log_message("Got message from $channel");
# good: using the decoded version of $channel
log_message("Got message from ".decode_irc($channel));
}
See also Encode, perluniintro, perlunitut, perlunicode, and perlunifaq.
AUTHOR
Hinrik Örn Sigurðsson <hinrik.sig@gmail.com> ("Hinrik" irc.perl.org, or
"literal" @ FreeNode).
Chris "BinGOs" Williams <chris@bingosnet.co.uk>
SEE ALSO
POE::Component::IRC
POE::Component::Server::IRC