FM / IO

/usr/lib/x86_64-linux-gnu/perl-base/IO

Name	Size	Mode	Actions
Socket/	-	0755	rm
File.pm	1636	0644	edit dl rm
Handle.pm	7700	0644	edit dl rm
Pipe.pm	3414	0644	edit dl rm
Seekable.pm	642	0644	edit dl rm
Select.pm	4714	0644	edit dl rm
Socket.pm	9938	0644	edit dl rm

Edit: /usr/lib/x86_64-linux-gnu/perl-base/IO/Select.pm (4714B)

# IO::Select.pm
#
# Copyright (c) 1997-8 Graham Barr <gbarr@pobox.com>. All rights reserved.
# This program is free software; you can redistribute it and/or
# modify it under the same terms as Perl itself.

package IO::Select;

use     strict;
use warnings::register;
require Exporter;

our $VERSION = "1.46";

our @ISA = qw(Exporter); # This is only so we can do version checking

sub VEC_BITS () {0}
sub FD_COUNT () {1}
sub FIRST_FD () {2}

sub new
{
 my $self = shift;
 my $type = ref($self) || $self;

my $vec = bless [undef,0], $type;

$vec->add(@_)
    if @_;

$vec;
}

sub add
{
 shift->_update('add', @_);
}

sub remove
{
 shift->_update('remove', @_);
}

sub exists
{
 my $vec = shift;
 my $fno = $vec->_fileno(shift);
 return undef unless defined $fno;
 $vec->[$fno + FIRST_FD];
}

sub _fileno
{
 my($self, $f) = @_;
 return unless defined $f;
 $f = $f->[0] if ref($f) eq 'ARRAY';
 if($f =~ /^[0-9]+$/) { # plain file number
  return $f;
 }
 elsif(defined(my $fd = fileno($f))) {
  return $fd;
 }
 else {
  # Neither a plain file number nor an opened filehandle; but maybe it was
  # previously registered and has since been closed. ->remove still wants to
  # know what fileno it had
  foreach my $i ( FIRST_FD .. $#$self ) {
   return $i - FIRST_FD if $self->[$i] == $f;
  }
  return undef;
 }
}

sub _update
{
 my $vec = shift;
 my $add = shift eq 'add';

my $bits = $vec->[VEC_BITS];
 $bits = '' unless defined $bits;

my $count = 0;
 my $f;
 foreach $f (@_)
  {
   my $fn = $vec->_fileno($f);
   if ($add) {
     next unless defined $fn;
     my $i = $fn + FIRST_FD;
     if (defined $vec->[$i]) {
	 $vec->[$i] = $f;  # if array rest might be different, so we update
	 next;
     }
     $vec->[FD_COUNT]++;
     vec($bits, $fn, 1) = 1;
     $vec->[$i] = $f;
   } else {      # remove
     if ( ! defined $fn ) { # remove if fileno undef'd
       $fn = 0;
       for my $fe (@{$vec}[FIRST_FD .. $#$vec]) {
         if (defined($fe) && $fe == $f) {
	   $vec->[FD_COUNT]--;
	   $fe = undef;
	   vec($bits, $fn, 1) = 0;
	   last;
	 }
	 ++$fn;
       }
     }
     else {
       my $i = $fn + FIRST_FD;
       next unless defined $vec->[$i];
       $vec->[FD_COUNT]--;
       vec($bits, $fn, 1) = 0;
       $vec->[$i] = undef;
     }
   }
   $count++;
  }
 $vec->[VEC_BITS] = $vec->[FD_COUNT] ? $bits : undef;
 $count;
}

sub can_read
{
 my $vec = shift;
 my $timeout = shift;
 my $r = $vec->[VEC_BITS];

defined($r) && (select($r,undef,undef,$timeout) > 0)
    ? handles($vec, $r)
    : ();
}

sub can_write
{
 my $vec = shift;
 my $timeout = shift;
 my $w = $vec->[VEC_BITS];

defined($w) && (select(undef,$w,undef,$timeout) > 0)
    ? handles($vec, $w)
    : ();
}

sub has_exception
{
 my $vec = shift;
 my $timeout = shift;
 my $e = $vec->[VEC_BITS];

defined($e) && (select(undef,undef,$e,$timeout) > 0)
    ? handles($vec, $e)
    : ();
}

sub has_error
{
 warnings::warn("Call to deprecated method 'has_error', use 'has_exception'")
	if warnings::enabled();
 goto &has_exception;
}

sub count
{
 my $vec = shift;
 $vec->[FD_COUNT];
}

sub bits
{
 my $vec = shift;
 $vec->[VEC_BITS];
}

sub as_string  # for debugging
{
 my $vec = shift;
 my $str = ref($vec) . ": ";
 my $bits = $vec->bits;
 my $count = $vec->count;
 $str .= defined($bits) ? unpack("b*", $bits) : "undef";
 $str .= " $count";
 my @handles = @$vec;
 splice(@handles, 0, FIRST_FD);
 for (@handles) {
     $str .= " " . (defined($_) ? "$_" : "-");
 }
 $str;
}

sub _max
{
 my($a,$b,$c) = @_;
 $a > $b
    ? $a > $c
        ? $a
        : $c
    : $b > $c
        ? $b
        : $c;
}

sub select
{
 shift
   if defined $_[0] && !ref($_[0]);

my($r,$w,$e,$t) = @_;
 my @result = ();

my $rb = defined $r ? $r->[VEC_BITS] : undef;
 my $wb = defined $w ? $w->[VEC_BITS] : undef;
 my $eb = defined $e ? $e->[VEC_BITS] : undef;

if(select($rb,$wb,$eb,$t) > 0)
  {
   my @r = ();
   my @w = ();
   my @e = ();
   my $i = _max(defined $r ? scalar(@$r)-1 : 0,
                defined $w ? scalar(@$w)-1 : 0,
                defined $e ? scalar(@$e)-1 : 0);

for( ; $i >= FIRST_FD ; $i--)
    {
     my $j = $i - FIRST_FD;
     push(@r, $r->[$i])
        if defined $rb && defined $r->[$i] && vec($rb, $j, 1);
     push(@w, $w->[$i])
        if defined $wb && defined $w->[$i] && vec($wb, $j, 1);
     push(@e, $e->[$i])
        if defined $eb && defined $e->[$i] && vec($eb, $j, 1);
    }

@result = (\@r, \@w, \@e);
  }
 @result;
}

sub handles
{
 my $vec = shift;
 my $bits = shift;
 my @h = ();
 my $i;
 my $max = scalar(@$vec) - 1;

for ($i = FIRST_FD; $i <= $max; $i++)
  {
   next unless defined $vec->[$i];
   push(@h, $vec->[$i])
      if !defined($bits) || vec($bits, $i - FIRST_FD, 1);
  }
 
 @h;
}

1;
__END__

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