Provided by: libirc-utils-perl_0.12-1_all 
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 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, 'ae`i')", where $channel is the unmodified channel name (a
byte string) you got from an earlier IRC message, the channel name will get double-encoded when
concatenated with your message (a non-ASCII text string) if the channel name contains non-ASCII bytes.
To prevent this, you can't simply decode the channel name and then use it. '#ae`i' in CP1252 is not the
same channel as '#ae`i' in UTF-8, since they are encoded as different sequences of bytes, and the IRC
server only cares about the byte representation. Therefore, when using a channel name you got from the
server (e.g. when replying to message), you should use the original byte string (before it has been
decoded with "decode_irc"), and encode any other parameters (with "encode_utf8") so that your message
will be concatenated correctly. At some point, you'll probably want to print the channel name, write it
to a log file or use it in a filename, so you'll eventually have to decode it, at which point the UTF-8
"#ae`i" and CP1252 "#ae`i" will have to be considered equivalent.
use Encode qw(encode_utf8 encode);
sub message_handler {
# these three are all byte strings
my ($nick, $channel, $message) = @_;
# bad: if $channel has any non-ASCII bytes, they will get double-encoded
privmsg($channel, 'ae`i');
# bad: if $message has any non-ASCII bytes, they will get double-encoded
privmsg('#ae`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('#ae`i', 'ae`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('#ae`i', 'ae`i');
# good: $channel and $msg_bytes are both byte strings
my $msg_bytes = encode_utf8('ae`i');
privmsg($channel, $msg_bytes);
# good: $chan_bytes and $message are both byte strings
# here we're sending a message to the utf8-encoded #ae`i
my $utf8_bytes = encode_utf8('#ae`i');
privmsg($utf8_bytes, $message);
# good: $chan_bytes and $message are both byte strings
# here we're sending a message to the cp1252-encoded #ae`i
my $cp1252_bytes = encode('cp1252', '#ae`i');
privmsg($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 Sigur`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