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');
$mode_change is now '-acd+fmZ'
"parse_user"¶
Takes one parameter, a string representing a user in the form
nick!user@hostname. In a scalar context it returns just the nickname. In a
list context it returns a list consisting of the nick, user and hostname,
respectively.
"is_valid_chan_name"¶
Takes one argument, a channel name to validate. Returns true or false if the
channel name is valid or not. You can supply a second argument, an array of
characters of allowed channel prefixes. Defaults to "['#',
'&']".
"is_valid_nick_name"¶
Takes one argument, a nickname to validate. Returns true or false if the
nickname is valid or not.
"numeric_to_name"¶
Takes an IRC server numerical reply code (e.g. '001') as an argument, and
returns the corresponding name (e.g. 'RPL_WELCOME').
"name_to_numeric"¶
Takes an IRC server reply name (e.g. 'RPL_WELCOME') as an argument, and returns
the corresponding numerical code (e.g. '001').
"has_color"¶
Takes one parameter, a string of IRC text. Returns true if it contains any IRC
color codes, false otherwise. Useful if you want your bot to kick users for
(ab)using colors. :)
Takes one parameter, a string of IRC text. Returns true if it contains any IRC
formatting codes, false otherwise.
"strip_color"¶
Takes one parameter, a string of IRC text. Returns the string stripped of all
IRC color codes.
Takes one parameter, a string of IRC text. Returns the string stripped of all
IRC formatting codes.
"decode_irc"¶
This function takes a byte string (i.e. an unmodified IRC message) and returns a
text string. Since the source encoding might have been UTF-8, you should store
it with UTF-8 or some other Unicode encoding in your file/database/whatever to
be safe. For a more detailed discussion, see "ENCODING".
use IRC::Utils qw(decode_irc);
sub message_handler {
my ($nick, $channel, $message) = @_;
# not wise, $message is a byte string of unknown 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, 'aed`i')", where $channel
is the unmodified channel name (a byte string) you got from an earlier IRC
message, the channel name will get double-encoded when concatenated with your
message (a non-ASCII text string) if the channel name contains non-ASCII
bytes.
To prevent this, you can't simply decode the channel name and then use it.
'#aed`i' in CP1252 is not the same channel as '#aed`i' in UTF-8, since they
are encoded as different sequences of bytes, and the IRC server only cares
about the byte representation. Therefore, when using a channel name you got
from the server (e.g. when replying to message), you should use the original
byte string (before it has been decoded with "decode_irc"), and
encode any other parameters (with "encode_utf8") so that your
message will be concatenated correctly. At some point, you'll probably want to
print the channel name, write it to a log file or use it in a filename, so
you'll eventually have to decode it, at which point the UTF-8
"#aed`i" and CP1252 "#aed`i" will have to be considered
equivalent.
use Encode qw(encode_utf8 encode);
sub message_handler {
# these three are all byte strings
my ($nick, $channel, $message) = @_;
# bad: if $channel has any non-ASCII bytes, they will get double-encoded
privmsg($channel, 'aed`i');
# bad: if $message has any non-ASCII bytes, they will get double-encoded
privmsg('#aed`i', $message);
# good: both are byte strings already, so they will concatenate correctly
privmsg($channel, $message);
# good: both are text strings (Latin1 as per Perl's default), so
# they'll be concatenated correctly
privmsg('#aed`i', 'aed`i');
# 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('#aed`i', 'aed`i');
# good: $channel and $msg_bytes are both byte strings
my $msg_bytes = encode_utf8('aed`i');
privmsg($channel, $msg_bytes);
# good: $chan_bytes and $message are both byte strings
# here we're sending a message to the utf8-encoded #aed`i
my $utf8_bytes = encode_utf8('#aed`i');
privmsg($utf8_bytes, $message);
# good: $chan_bytes and $message are both byte strings
# here we're sending a message to the cp1252-encoded #aed`i
my $cp1252_bytes = encode('cp1252', '#aed`i');
privmsg($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 Oern Sigurd`sson <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