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Diffstat (limited to 'Master/tlpkg/tlperl.old/lib/IO/Select.pm')
-rw-r--r-- | Master/tlpkg/tlperl.old/lib/IO/Select.pm | 381 |
1 files changed, 381 insertions, 0 deletions
diff --git a/Master/tlpkg/tlperl.old/lib/IO/Select.pm b/Master/tlpkg/tlperl.old/lib/IO/Select.pm new file mode 100644 index 00000000000..fc05fe70e9c --- /dev/null +++ b/Master/tlpkg/tlperl.old/lib/IO/Select.pm @@ -0,0 +1,381 @@ +# 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; +use vars qw($VERSION @ISA); +require Exporter; + +$VERSION = "1.17"; + +@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'; + ($f =~ /^\d+$/) ? $f : fileno($f); +} + +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); + next unless defined $fn; + my $i = $fn + FIRST_FD; + if ($add) { + 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 + 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__ + +=head1 NAME + +IO::Select - OO interface to the select system call + +=head1 SYNOPSIS + + use IO::Select; + + $s = IO::Select->new(); + + $s->add(\*STDIN); + $s->add($some_handle); + + @ready = $s->can_read($timeout); + + @ready = IO::Select->new(@handles)->can_read(0); + +=head1 DESCRIPTION + +The C<IO::Select> package implements an object approach to the system C<select> +function call. It allows the user to see what IO handles, see L<IO::Handle>, +are ready for reading, writing or have an exception pending. + +=head1 CONSTRUCTOR + +=over 4 + +=item new ( [ HANDLES ] ) + +The constructor creates a new object and optionally initialises it with a set +of handles. + +=back + +=head1 METHODS + +=over 4 + +=item add ( HANDLES ) + +Add the list of handles to the C<IO::Select> object. It is these values that +will be returned when an event occurs. C<IO::Select> keeps these values in a +cache which is indexed by the C<fileno> of the handle, so if more than one +handle with the same C<fileno> is specified then only the last one is cached. + +Each handle can be an C<IO::Handle> object, an integer or an array +reference where the first element is an C<IO::Handle> or an integer. + +=item remove ( HANDLES ) + +Remove all the given handles from the object. This method also works +by the C<fileno> of the handles. So the exact handles that were added +need not be passed, just handles that have an equivalent C<fileno> + +=item exists ( HANDLE ) + +Returns a true value (actually the handle itself) if it is present. +Returns undef otherwise. + +=item handles + +Return an array of all registered handles. + +=item can_read ( [ TIMEOUT ] ) + +Return an array of handles that are ready for reading. C<TIMEOUT> is +the maximum amount of time to wait before returning an empty list, in +seconds, possibly fractional. If C<TIMEOUT> is not given and any +handles are registered then the call will block. + +=item can_write ( [ TIMEOUT ] ) + +Same as C<can_read> except check for handles that can be written to. + +=item has_exception ( [ TIMEOUT ] ) + +Same as C<can_read> except check for handles that have an exception +condition, for example pending out-of-band data. + +=item count () + +Returns the number of handles that the object will check for when +one of the C<can_> methods is called or the object is passed to +the C<select> static method. + +=item bits() + +Return the bit string suitable as argument to the core select() call. + +=item select ( READ, WRITE, EXCEPTION [, TIMEOUT ] ) + +C<select> is a static method, that is you call it with the package name +like C<new>. C<READ>, C<WRITE> and C<EXCEPTION> are either C<undef> or +C<IO::Select> objects. C<TIMEOUT> is optional and has the same effect as +for the core select call. + +The result will be an array of 3 elements, each a reference to an array +which will hold the handles that are ready for reading, writing and have +exceptions respectively. Upon error an empty list is returned. + +=back + +=head1 EXAMPLE + +Here is a short example which shows how C<IO::Select> could be used +to write a server which communicates with several sockets while also +listening for more connections on a listen socket + + use IO::Select; + use IO::Socket; + + $lsn = new IO::Socket::INET(Listen => 1, LocalPort => 8080); + $sel = new IO::Select( $lsn ); + + while(@ready = $sel->can_read) { + foreach $fh (@ready) { + if($fh == $lsn) { + # Create a new socket + $new = $lsn->accept; + $sel->add($new); + } + else { + # Process socket + + # Maybe we have finished with the socket + $sel->remove($fh); + $fh->close; + } + } + } + +=head1 AUTHOR + +Graham Barr. Currently maintained by the Perl Porters. Please report all +bugs to <perl5-porters@perl.org>. + +=head1 COPYRIGHT + +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. + +=cut + |