Coro/Coro/Handle.pm

=head1 NAME

Coro::Handle - non-blocking io with a blocking interface.

=head1 SYNOPSIS

 use Coro::Handle;

=head1 DESCRIPTION

This module implements IO-handles in a coroutine-compatible way, that is,
other coroutines can run while reads or writes block on the handle.

It does so by using L<AnyEvent|AnyEvent> to wait for readable/writable
data, allowing other coroutines to run while one coroutine waits for I/O.

Coro::Handle does NOT inherit from IO::Handle but uses tied objects.

If at all possible, you should I<always> prefer method calls on the handle object over invoking
tied methods, i.e.:

   $fh->print ($str);         # NOT print $fh $str;
   my $line = $fh->readline;  # NOT my $line = <$fh>;

The reason is that perl recurses within the interpreter when invoking tie
magic, forcing the (temporary) allocation of a (big) stack. If you have
lots of socket connections and they happen to wait in e.g. <$fh>, then
they would all have a costly C coroutine associated with them.

=over 4

=cut

package Coro::Handle;

no warnings;
use strict;

use Carp ();
use Errno ();
use base 'Exporter';

our $VERSION = '3.0';
our @EXPORT = qw(unblock);

=item $fh = new_from_fh Coro::Handle $fhandle [, arg => value...]

Create a new non-blocking io-handle using the given
perl-filehandle. Returns C<undef> if no filehandle is given. The only
other supported argument is "timeout", which sets a timeout for each
operation.

=cut

sub new_from_fh {
   my $class = shift;
   my $fh = shift or return;
   my $self = do { local *Coro::Handle };

   tie $self, 'Coro::Handle::FH', fh => $fh, @_;

   bless \$self, ref $class ? ref $class : $class
}

=item $fh = unblock $fh

This is a convinience function that just calls C<new_from_fh> on the
given filehandle. Use it to replace a normal perl filehandle by a
non-(coroutine-)blocking equivalent.

=cut

sub unblock($) {
   new_from_fh Coro::Handle $_[0]
}

=item $fh->writable, $fh->readable

Wait until the filehandle is readable or writable (and return true) or
until an error condition happens (and return false).

=cut

sub readable    { Coro::Handle::FH::readable (tied ${$_[0]}) }
sub writable    { Coro::Handle::FH::writable (tied ${$_[0]}) }

=item $fh->readline ([$terminator])

Like the builtin of the same name, but allows you to specify the input
record separator in a coroutine-safe manner (i.e. not using a global
variable).

=cut

sub readline    { tied(${+shift})->READLINE (@_) }

=item $fh->autoflush ([...])

Always returns true, arguments are being ignored (exists for compatibility
only). Might change in the future.

=cut

sub autoflush   { !0 }

=item $fh->fileno, $fh->close, $fh->read, $fh->sysread, $fh->syswrite, $fh->print, $fh->printf

Work like their function equivalents (except read, which works like
sysread. You should not use the read function with Coro::Handle's, it will
work but it's not efficient).

=cut

sub read        { Coro::Handle::FH::READ   (tied ${$_[0]}, $_[1], $_[2], $_[3]) }
sub sysread     { Coro::Handle::FH::READ   (tied ${$_[0]}, $_[1], $_[2], $_[3]) }
sub syswrite    { Coro::Handle::FH::WRITE  (tied ${$_[0]}, $_[1], $_[2], $_[3]) }
sub print       { Coro::Handle::FH::WRITE  (tied ${+shift}, join "", @_) }
sub printf      { Coro::Handle::FH::PRINTF (tied ${+shift}, @_) }
sub fileno      { Coro::Handle::FH::FILENO (tied ${$_[0]}) }
sub close       { Coro::Handle::FH::CLOSE  (tied ${$_[0]}) }
sub blocking    { !0 } # this handler always blocks the caller

sub partial     {
   my $obj = tied ${$_[0]};

   my $retval = $obj->[8];
   $obj->[8] = $_[1] if @_ > 1;
   $retval
}

=item connect, listen, bind, getsockopt, setsockopt,
send, recv, peername, sockname, shutdown, peerport, peerhost

Do the same thing as the perl builtins or IO::Socket methods (but return
true on EINPROGRESS). Remember that these must be method calls.

=cut

sub connect     { connect     tied(${$_[0]})->[0], $_[1] or $! == Errno::EINPROGRESS }
sub bind        { bind        tied(${$_[0]})->[0], $_[1] }
sub listen      { listen      tied(${$_[0]})->[0], $_[1] }
sub getsockopt  { getsockopt  tied(${$_[0]})->[0], $_[1], $_[2] }
sub setsockopt  { setsockopt  tied(${$_[0]})->[0], $_[1], $_[2], $_[3] }
sub send        { send        tied(${$_[0]})->[0], $_[1], $_[2], @_ > 2 ? $_[3] : () }
sub recv        { recv        tied(${$_[0]})->[0], $_[1], $_[2], @_ > 2 ? $_[3] : () }
sub sockname    { getsockname tied(${$_[0]})->[0] }
sub peername    { getpeername tied(${$_[0]})->[0] }
sub shutdown    { shutdown    tied(${$_[0]})->[0], $_[1] }

=item ($fh, $peername) = $listen_fh->accept

In scalar context, returns the newly accepted socket (or undef) and in
list context return the ($fh, $peername) pair (or nothing).

=cut

sub accept {
   my ($peername, $fh);
   while () {
      $peername = accept $fh, tied(${$_[0]})->[0]
         and return wantarray 
                    ? ($_[0]->new_from_fh($fh), $peername)
                    :  $_[0]->new_from_fh($fh);

      return unless $!{EAGAIN};

      $_[0]->readable or return;
   }
}

=item $fh->timeout ([...])

The optional argument sets the new timeout (in seconds) for this
handle. Returns the current (new) value.

C<0> is a valid timeout, use C<undef> to disable the timeout.

=cut

sub timeout {
   my $self = tied ${$_[0]};
   if (@_ > 1) {
      $self->[2] = $_[1];
      $self->[5]->timeout ($_[1]) if $self->[5];
      $self->[6]->timeout ($_[1]) if $self->[6];
   }
   $self->[2]
}

=item $fh->fh

Returns the "real" (non-blocking) filehandle. Use this if you want to
do operations on the file handle you cannot do using the Coro::Handle
interface.

=item $fh->rbuf

Returns the current contents of the read buffer (this is an lvalue, so you
can change the read buffer if you like).

You can use this function to implement your own optimized reader when neither
readline nor sysread are viable candidates, like this:

  # first get the _real_ non-blocking filehandle
  # and fetch a reference to the read buffer
  my $nb_fh = $fh->fh;
  my $buf = \$fh->rbuf;

  while () {
     # now use buffer contents, modifying
     # if necessary to reflect the removed data

     last if $$buf ne ""; # we have leftover data

     # read another buffer full of data
     $fh->readable or die "end of file";
     sysread $nb_fh, $$buf, 8192;
  }

=cut

sub fh {
   (tied ${$_[0]})->[0];
}

sub rbuf : lvalue {
   (tied ${$_[0]})->[3];
}

sub DESTROY {
   # nop
}

our $AUTOLOAD;

sub AUTOLOAD {
   my $self = tied ${$_[0]};

   (my $func = $AUTOLOAD) =~ s/^(.*):://;

   my $forward = UNIVERSAL::can $self->[7], $func;

   $forward or
      die "Can't locate object method \"$func\" via package \"" . (ref $self) . "\"";

   goto &$forward;
}

package Coro::Handle::FH;

no warnings;
use strict;

use Fcntl ();
use Errno ();
use Carp 'croak';

use AnyEvent;

# formerly a hash, but we are speed-critical, so try
# to be faster even if it hurts.
#
# 0 FH
# 1 desc
# 2 timeout
# 3 rb
# 4 wb # unused
# 5 read watcher, if Coro::Event used
# 6 write watcher, if Coro::Event used
# 7 forward class
# 8 blocking

sub TIEHANDLE {
   my ($class, %arg) = @_;

   my $self = bless [], $class;
   $self->[0] = $arg{fh};
   $self->[1] = $arg{desc};
   $self->[2] = $arg{timeout};
   $self->[3] = "";
   $self->[4] = "";
   $self->[7] = $arg{forward_class};
   $self->[8] = $arg{partial};

   fcntl $self->[0], &Fcntl::F_SETFL, &Fcntl::O_NONBLOCK
      or croak "fcntl(O_NONBLOCK): $!";

   $self
}

sub cleanup {
   $_[0][5]->cancel if $_[0][5];
   $_[0][6]->cancel if $_[0][6];
   @{$_[0]} = ();
}

sub OPEN {
   &cleanup;
   my $self = shift;
   my $r = @_ == 2 ? open $self->[0], $_[0], $_[1]
                   : open $self->[0], $_[0], $_[1], $_[2];

   if ($r) {
      fcntl $self->[0], &Fcntl::F_SETFL, &Fcntl::O_NONBLOCK
         or croak "fcntl(O_NONBLOCK): $!";
   }

   $r
}

sub PRINT {
   WRITE (shift, join "", @_)
}

sub PRINTF {
   WRITE (shift, sprintf shift,@_)
}

sub GETC {
   my $buf;
   READ ($_[0], $buf, 1);
   $buf
}

sub BINMODE {
   binmode $_[0][0];
}

sub TELL {
   Carp::croak "Coro::Handle's don't support tell()";
}

sub SEEK {
   Carp::croak "Coro::Handle's don't support seek()";
}

sub EOF {
   Carp::croak "Coro::Handle's don't support eof()";
}

sub CLOSE {
   &cleanup;
   close $_[0][0]
}

sub DESTROY {
   &cleanup;
}

sub FILENO {
   fileno $_[0][0]
}

# seems to be called for stringification (how weird), at least
# when DumpValue::dumpValue is used to print this.
sub FETCH {
   "$_[0]<$_[0][1]>"
}

sub readable_anyevent {
   my $current = $Coro::current;
   my $io = 1;

   my $w = AnyEvent->io (
      desc  => "$_[0][1] read watcher",
      fh    => $_[0][0],
      poll  => 'r',
      cb    => sub {
         $current->ready;
         undef $current;
      },
   );

   my $t = (defined $_[0][2]) && AnyEvent->timer (
      desc  => "fh $_[0][1] read timeout",
      after => $_[0][2],
      cb    => sub {
         $io = 0;
         $current->ready;
         undef $current;
      },
   );

   &Coro::schedule;
   &Coro::schedule while $current;

   $io
}

sub writable_anyevent {
   my $current = $Coro::current;
   my $io = 1;

   my $w = AnyEvent->io (
      desc  => "fh $_[0][1] write watcher",
      fh    => $_[0][0],
      poll  => 'w',
      cb    => sub {
         $current->ready;
         undef $current;
      },
   );

   my $t = (defined $_[0][2]) && AnyEvent->timer (
      desc  => "fh $_[0][1] write timeout",
      after => $_[0][2],
      cb    => sub {
         $io = 0;
         $current->ready;
         undef $current;
      },
   );

   &Coro::schedule while $current;

   $io
}

sub readable_coro {
   ($_[0][5] ||= "Coro::Event"->io (
      fd      => $_[0][0],
      desc    => "fh $_[0][1] read watcher",
      timeout => $_[0][2],
      poll    => &Event::Watcher::R + &Event::Watcher::E + &Event::Watcher::T,
   ))->next->[4] & &Event::Watcher::R
}

sub writable_coro {
   ($_[0][6] ||= "Coro::Event"->io (
      fd      => $_[0][0],
      desc    => "fh $_[0][1] write watcher",
      timeout => $_[0][2],
      poll    => &Event::Watcher::W + &Event::Watcher::E + &Event::Watcher::T,
   ))->next->[4] & &Event::Watcher::W
}

# decide on event model at runtime
for my $rw (qw(readable writable)) {
   no strict 'refs';

   *$rw = sub {
      AnyEvent::detect;
      if ($AnyEvent::MODEL eq "AnyEvent::Impl::Coro" or $AnyEvent::MODEL eq "AnyEvent::Impl::Event") {
         require Coro::Event;
         *$rw = \&{"$rw\_coro"};
      } else {
         *$rw = \&{"$rw\_anyevent"};
      }
      goto &$rw
   };
};

sub WRITE {
   my $len = defined $_[2] ? $_[2] : length $_[1];
   my $ofs = $_[3];
   my $res = 0;

   while () {
      my $r = syswrite ($_[0][0], $_[1], $len, $ofs);
      if (defined $r) {
         $len -= $r;
         $ofs += $r;
         $res += $r;
         last unless $len;
      } elsif ($! != Errno::EAGAIN) {
         last;
      }
      last unless &writable;
   }

   return $res;
}

sub READ {
   my $len = $_[2];
   my $ofs = $_[3];
   my $res = 0;

   # first deplete the read buffer
   if (length $_[0][3]) {
      my $l = length $_[0][3];
      if ($l <= $len) {
         substr ($_[1], $ofs) = $_[0][3]; $_[0][3] = "";
         $len -= $l;
         $ofs += $l;
         $res += $l;
         return $res unless $len;
      } else {
         substr ($_[1], $ofs) = substr ($_[0][3], 0, $len);
         substr ($_[0][3], 0, $len) = "";
         return $len;
      }
   }

   while() {
      my $r = sysread $_[0][0], $_[1], $len, $ofs;
      if (defined $r) {
         $len -= $r;
         $ofs += $r;
         $res += $r;
         last unless $len && $r;
      } elsif ($! != Errno::EAGAIN) {
         last;
      }
      last if $_[0][8] || !&readable;
   }

   return $res;
}

sub READLINE {
   my $irs = @_ > 1 ? $_[1] : $/;

   while() {
      if (defined $irs) {
         my $pos = index $_[0][3], $irs;
         if ($pos >= 0) {
            $pos += length $irs;
            my $res = substr $_[0][3], 0, $pos;
            substr ($_[0][3], 0, $pos) = "";
            return $res;
         }
      }

      my $r = sysread $_[0][0], $_[0][3], 8192, length $_[0][3];
      if (defined $r) {
         return length $_[0][3] ? delete $_[0][3] : undef unless $r;
      } elsif ($! != Errno::EAGAIN || !&readable) {
         return length $_[0][3] ? delete $_[0][3] : undef;
      }
   }
}

1;

=back

=head1 BUGS

 - Perl's IO-Handle model is THE bug.

=head1 AUTHOR

 Marc Lehmann <schmorp@schmorp.de>
 http://home.schmorp.de/

=cut

Revision:	1.29
Committed:	Thu Oct 25 08:14:00 2007 UTC (16 years, 7 months ago) by root
Branch:	MAIN
Changes since 1.28:	+3 -4 lines
Log Message:	* empty log message *
#	User	Rev	Content
1	root	1.1	=head1 NAME
2
3			Coro::Handle - non-blocking io with a blocking interface.
4
5			=head1 SYNOPSIS
6
7			use Coro::Handle;
8
9			=head1 DESCRIPTION
10
11	root	1.13	This module implements IO-handles in a coroutine-compatible way, that is,
12	root	1.14	other coroutines can run while reads or writes block on the handle.
13
14			It does so by using L<AnyEvent\|AnyEvent> to wait for readable/writable
15			data, allowing other coroutines to run while one coroutine waits for I/O.
16
17			Coro::Handle does NOT inherit from IO::Handle but uses tied objects.
18	root	1.1
19	root	1.28	If at all possible, you should I<always> prefer method calls on the handle object over invoking
20			tied methods, i.e.:
21
22			$fh->print ($str); # NOT print $fh $str;
23			my $line = $fh->readline; # NOT my $line = <$fh>;
24
25			The reason is that perl recurses within the interpreter when invoking tie
26			magic, forcing the (temporary) allocation of a (big) stack. If you have
27			lots of socket connections and they happen to wait in e.g. <$fh>, then
28			they would all have a costly C coroutine associated with them.
29
30	root	1.1	=over 4
31
32			=cut
33
34			package Coro::Handle;
35
36	root	1.16	no warnings;
37			use strict;
38	root	1.13
39	root	1.16	use Carp ();
40	root	1.1	use Errno ();
41	root	1.5	use base 'Exporter';
42	root	1.1
43	root	1.22	our $VERSION = '3.0';
44	root	1.16	our @EXPORT = qw(unblock);
45	root	1.1
46	root	1.6	=item $fh = new_from_fh Coro::Handle $fhandle [, arg => value...]
47	root	1.1
48			Create a new non-blocking io-handle using the given
49	root	1.19	perl-filehandle. Returns C<undef> if no filehandle is given. The only
50			other supported argument is "timeout", which sets a timeout for each
51			operation.
52	root	1.1
53			=cut
54
55			sub new_from_fh {
56			my $class = shift;
57			my $fh = shift or return;
58			my $self = do { local *Coro::Handle };
59
60	root	1.20	tie $self, 'Coro::Handle::FH', fh => $fh, @_;
61	root	1.1
62	root	1.22	bless \$self, ref $class ? ref $class : $class
63	root	1.1	}
64
65	root	1.5	=item $fh = unblock $fh
66
67	root	1.22	This is a convinience function that just calls C<new_from_fh> on the
68			given filehandle. Use it to replace a normal perl filehandle by a
69			non-(coroutine-)blocking equivalent.
70	root	1.5
71			=cut
72
73			sub unblock($) {
74	root	1.19	new_from_fh Coro::Handle $_[0]
75	root	1.5	}
76
77	root	1.1	=item $fh->writable, $fh->readable
78
79			Wait until the filehandle is readable or writable (and return true) or
80			until an error condition happens (and return false).
81
82			=cut
83
84	root	1.16	sub readable { Coro::Handle::FH::readable (tied ${$_[0]}) }
85			sub writable { Coro::Handle::FH::writable (tied ${$_[0]}) }
86	root	1.1
87	root	1.16	=item $fh->readline ([$terminator])
88	root	1.4
89			Like the builtin of the same name, but allows you to specify the input
90	root	1.7	record separator in a coroutine-safe manner (i.e. not using a global
91	root	1.4	variable).
92
93			=cut
94
95	root	1.18	sub readline { tied(${+shift})->READLINE (@_) }
96	root	1.4
97	root	1.16	=item $fh->autoflush ([...])
98	root	1.4
99			Always returns true, arguments are being ignored (exists for compatibility
100	root	1.8	only). Might change in the future.
101	root	1.4
102			=cut
103
104			sub autoflush { !0 }
105
106	root	1.13	=item $fh->fileno, $fh->close, $fh->read, $fh->sysread, $fh->syswrite, $fh->print, $fh->printf
107	root	1.8
108	root	1.13	Work like their function equivalents (except read, which works like
109	root	1.18	sysread. You should not use the read function with Coro::Handle's, it will
110	root	1.13	work but it's not efficient).
111	root	1.8
112			=cut
113
114	root	1.13	sub read { Coro::Handle::FH::READ (tied ${$_[0]}, $_[1], $_[2], $_[3]) }
115			sub sysread { Coro::Handle::FH::READ (tied ${$_[0]}, $_[1], $_[2], $_[3]) }
116			sub syswrite { Coro::Handle::FH::WRITE (tied ${$_[0]}, $_[1], $_[2], $_[3]) }
117			sub print { Coro::Handle::FH::WRITE (tied ${+shift}, join "", @_) }
118			sub printf { Coro::Handle::FH::PRINTF (tied ${+shift}, @_) }
119			sub fileno { Coro::Handle::FH::FILENO (tied ${$_[0]}) }
120			sub close { Coro::Handle::FH::CLOSE (tied ${$_[0]}) }
121			sub blocking { !0 } # this handler always blocks the caller
122
123			sub partial {
124			my $obj = tied ${$_[0]};
125
126			my $retval = $obj->[8];
127			$obj->[8] = $_[1] if @_ > 1;
128			$retval
129			}
130	root	1.8
131	root	1.27	=item connect, listen, bind, getsockopt, setsockopt,
132			send, recv, peername, sockname, shutdown, peerport, peerhost
133
134			Do the same thing as the perl builtins or IO::Socket methods (but return
135			true on EINPROGRESS). Remember that these must be method calls.
136
137			=cut
138
139			sub connect { connect tied(${$_[0]})->[0], $_[1] or $! == Errno::EINPROGRESS }
140			sub bind { bind tied(${$_[0]})->[0], $_[1] }
141			sub listen { listen tied(${$_[0]})->[0], $_[1] }
142			sub getsockopt { getsockopt tied(${$_[0]})->[0], $_[1], $_[2] }
143			sub setsockopt { setsockopt tied(${$_[0]})->[0], $_[1], $_[2], $_[3] }
144			sub send { send tied(${$_[0]})->[0], $_[1], $_[2], @_ > 2 ? $_[3] : () }
145			sub recv { recv tied(${$_[0]})->[0], $_[1], $_[2], @_ > 2 ? $_[3] : () }
146			sub sockname { getsockname tied(${$_[0]})->[0] }
147			sub peername { getpeername tied(${$_[0]})->[0] }
148			sub shutdown { shutdown tied(${$_[0]})->[0], $_[1] }
149
150			=item ($fh, $peername) = $listen_fh->accept
151
152			In scalar context, returns the newly accepted socket (or undef) and in
153			list context return the ($fh, $peername) pair (or nothing).
154
155			=cut
156
157			sub accept {
158			my ($peername, $fh);
159			while () {
160			$peername = accept $fh, tied(${$_[0]})->[0]
161			and return wantarray
162			? ($_[0]->new_from_fh($fh), $peername)
163			: $_[0]->new_from_fh($fh);
164
165			return unless $!{EAGAIN};
166
167			$_[0]->readable or return;
168			}
169			}
170
171	root	1.21	=item $fh->timeout ([...])
172	root	1.8
173	root	1.13	The optional argument sets the new timeout (in seconds) for this
174	root	1.8	handle. Returns the current (new) value.
175
176			C<0> is a valid timeout, use C<undef> to disable the timeout.
177
178			=cut
179
180			sub timeout {
181	root	1.18	my $self = tied ${$_[0]};
182	root	1.13	if (@_ > 1) {
183			$self->[2] = $_[1];
184	root	1.18	$self->[5]->timeout ($_[1]) if $self->[5];
185			$self->[6]->timeout ($_[1]) if $self->[6];
186	root	1.8	}
187	root	1.21	$self->[2]
188	root	1.13	}
189
190			=item $fh->fh
191
192			Returns the "real" (non-blocking) filehandle. Use this if you want to
193			do operations on the file handle you cannot do using the Coro::Handle
194			interface.
195
196			=item $fh->rbuf
197
198			Returns the current contents of the read buffer (this is an lvalue, so you
199			can change the read buffer if you like).
200
201			You can use this function to implement your own optimized reader when neither
202			readline nor sysread are viable candidates, like this:
203
204			# first get the _real_ non-blocking filehandle
205			# and fetch a reference to the read buffer
206			my $nb_fh = $fh->fh;
207			my $buf = \$fh->rbuf;
208
209	root	1.18	while () {
210	root	1.13	# now use buffer contents, modifying
211			# if necessary to reflect the removed data
212
213			last if $$buf ne ""; # we have leftover data
214
215			# read another buffer full of data
216			$fh->readable or die "end of file";
217			sysread $nb_fh, $$buf, 8192;
218			}
219
220			=cut
221
222			sub fh {
223			(tied ${$_[0]})->[0];
224			}
225
226			sub rbuf : lvalue {
227			(tied ${$_[0]})->[3];
228			}
229
230			sub DESTROY {
231			# nop
232			}
233
234	root	1.16	our $AUTOLOAD;
235
236	root	1.13	sub AUTOLOAD {
237			my $self = tied ${$_[0]};
238
239			(my $func = $AUTOLOAD) =~ s/^(.*):://;
240
241			my $forward = UNIVERSAL::can $self->[7], $func;
242
243			$forward or
244			die "Can't locate object method \"$func\" via package \"" . (ref $self) . "\"";
245
246			goto &$forward;
247	root	1.8	}
248
249	root	1.1	package Coro::Handle::FH;
250
251	root	1.16	no warnings;
252			use strict;
253	root	1.13
254	root	1.1	use Fcntl ();
255			use Errno ();
256	root	1.10	use Carp 'croak';
257	root	1.1
258	root	1.13	use AnyEvent;
259	root	1.1
260	root	1.13	# formerly a hash, but we are speed-critical, so try
261			# to be faster even if it hurts.
262			#
263			# 0 FH
264			# 1 desc
265			# 2 timeout
266			# 3 rb
267			# 4 wb # unused
268	root	1.17	# 5 read watcher, if Coro::Event used
269			# 6 write watcher, if Coro::Event used
270	root	1.13	# 7 forward class
271			# 8 blocking
272	root	1.1
273			sub TIEHANDLE {
274	root	1.13	my ($class, %arg) = @_;
275	root	1.1
276	root	1.13	my $self = bless [], $class;
277			$self->[0] = $arg{fh};
278			$self->[1] = $arg{desc};
279			$self->[2] = $arg{timeout};
280			$self->[3] = "";
281			$self->[4] = "";
282			$self->[7] = $arg{forward_class};
283			$self->[8] = $arg{partial};
284	root	1.1
285	root	1.13	fcntl $self->[0], &Fcntl::F_SETFL, &Fcntl::O_NONBLOCK
286	root	1.10	or croak "fcntl(O_NONBLOCK): $!";
287	root	1.6
288	root	1.13	$self
289			}
290
291			sub cleanup {
292	root	1.29	$_[0][5]->cancel if $_[0][5];
293			$_[0][6]->cancel if $_[0][6];
294			@{$_[0]} = ();
295	root	1.1	}
296
297			sub OPEN {
298	root	1.13	&cleanup;
299	root	1.1	my $self = shift;
300	root	1.13	my $r = @_ == 2 ? open $self->[0], $_[0], $_[1]
301			: open $self->[0], $_[0], $_[1], $_[2];
302	root	1.18
303	root	1.1	if ($r) {
304	root	1.13	fcntl $self->[0], &Fcntl::F_SETFL, &Fcntl::O_NONBLOCK
305	root	1.10	or croak "fcntl(O_NONBLOCK): $!";
306	root	1.1	}
307	root	1.18
308			$r
309	root	1.1	}
310
311	root	1.13	sub PRINT {
312	root	1.18	WRITE (shift, join "", @_)
313	root	1.13	}
314
315			sub PRINTF {
316	root	1.18	WRITE (shift, sprintf shift,@_)
317	root	1.13	}
318
319			sub GETC {
320			my $buf;
321	root	1.16	READ ($_[0], $buf, 1);
322	root	1.18	$buf
323	root	1.13	}
324
325			sub BINMODE {
326			binmode $_[0][0];
327			}
328
329			sub TELL {
330	root	1.16	Carp::croak "Coro::Handle's don't support tell()";
331	root	1.13	}
332
333			sub SEEK {
334	root	1.16	Carp::croak "Coro::Handle's don't support seek()";
335	root	1.13	}
336
337			sub EOF {
338	root	1.16	Carp::croak "Coro::Handle's don't support eof()";
339	root	1.13	}
340
341	root	1.1	sub CLOSE {
342	root	1.13	&cleanup;
343	root	1.18	close $_[0][0]
344	root	1.13	}
345
346			sub DESTROY {
347			&cleanup;
348	root	1.8	}
349
350			sub FILENO {
351	root	1.18	fileno $_[0][0]
352	root	1.1	}
353
354	root	1.13	# seems to be called for stringification (how weird), at least
355			# when DumpValue::dumpValue is used to print this.
356			sub FETCH {
357	root	1.18	"$_[0]<$_[0][1]>"
358	root	1.1	}
359
360	root	1.17	sub readable_anyevent {
361	root	1.13	my $current = $Coro::current;
362			my $io = 1;
363
364			my $w = AnyEvent->io (
365	root	1.16	desc => "$_[0][1] read watcher",
366			fh => $_[0][0],
367			poll => 'r',
368			cb => sub {
369	root	1.13	$current->ready;
370	root	1.15	undef $current;
371	root	1.13	},
372			);
373
374	root	1.16	my $t = (defined $_[0][2]) && AnyEvent->timer (
375			desc => "fh $_[0][1] read timeout",
376	root	1.13	after => $_[0][2],
377			cb => sub {
378			$io = 0;
379			$current->ready;
380	root	1.15	undef $current;
381	root	1.13	},
382			);
383
384			&Coro::schedule;
385	root	1.15	&Coro::schedule while $current;
386
387	root	1.13	$io
388			}
389
390	root	1.17	sub writable_anyevent {
391	root	1.13	my $current = $Coro::current;
392			my $io = 1;
393
394			my $w = AnyEvent->io (
395	root	1.16	desc => "fh $_[0][1] write watcher",
396			fh => $_[0][0],
397			poll => 'w',
398			cb => sub {
399	root	1.13	$current->ready;
400	root	1.15	undef $current;
401	root	1.13	},
402			);
403
404	root	1.16	my $t = (defined $_[0][2]) && AnyEvent->timer (
405			desc => "fh $_[0][1] write timeout",
406	root	1.13	after => $_[0][2],
407			cb => sub {
408			$io = 0;
409			$current->ready;
410	root	1.15	undef $current;
411	root	1.13	},
412			);
413
414	root	1.15	&Coro::schedule while $current;
415
416	root	1.13	$io
417	root	1.1	}
418
419	root	1.17	sub readable_coro {
420	root	1.18	($_[0][5] \|\|= "Coro::Event"->io (
421	root	1.17	fd => $_[0][0],
422			desc => "fh $_[0][1] read watcher",
423			timeout => $_[0][2],
424			poll => &Event::Watcher::R + &Event::Watcher::E + &Event::Watcher::T,
425	root	1.26	))->next->[4] & &Event::Watcher::R
426	root	1.17	}
427
428			sub writable_coro {
429	root	1.18	($_[0][6] \|\|= "Coro::Event"->io (
430	root	1.17	fd => $_[0][0],
431			desc => "fh $_[0][1] write watcher",
432			timeout => $_[0][2],
433			poll => &Event::Watcher::W + &Event::Watcher::E + &Event::Watcher::T,
434	root	1.26	))->next->[4] & &Event::Watcher::W
435	root	1.17	}
436
437	root	1.21	# decide on event model at runtime
438	root	1.17	for my $rw (qw(readable writable)) {
439			no strict 'refs';
440
441			*$rw = sub {
442	root	1.25	AnyEvent::detect;
443	root	1.17	if ($AnyEvent::MODEL eq "AnyEvent::Impl::Coro" or $AnyEvent::MODEL eq "AnyEvent::Impl::Event") {
444			require Coro::Event;
445			*$rw = \&{"$rw\_coro"};
446			} else {
447			*$rw = \&{"$rw\_anyevent"};
448			}
449	root	1.25	goto &$rw
450	root	1.17	};
451			};
452
453	root	1.1	sub WRITE {
454			my $len = defined $_[2] ? $_[2] : length $_[1];
455			my $ofs = $_[3];
456			my $res = 0;
457
458	root	1.16	while () {
459			my $r = syswrite ($_[0][0], $_[1], $len, $ofs);
460	root	1.1	if (defined $r) {
461			$len -= $r;
462			$ofs += $r;
463			$res += $r;
464			last unless $len;
465			} elsif ($! != Errno::EAGAIN) {
466			last;
467			}
468	root	1.13	last unless &writable;
469	root	1.1	}
470
471			return $res;
472			}
473
474			sub READ {
475			my $len = $_[2];
476			my $ofs = $_[3];
477			my $res = 0;
478
479	root	1.7	# first deplete the read buffer
480	root	1.13	if (length $_[0][3]) {
481			my $l = length $_[0][3];
482	root	1.7	if ($l <= $len) {
483	root	1.18	substr ($_[1], $ofs) = $_[0][3]; $_[0][3] = "";
484	root	1.7	$len -= $l;
485	root	1.13	$ofs += $l;
486	root	1.7	$res += $l;
487			return $res unless $len;
488			} else {
489	root	1.18	substr ($_[1], $ofs) = substr ($_[0][3], 0, $len);
490			substr ($_[0][3], 0, $len) = "";
491	root	1.7	return $len;
492			}
493			}
494
495	root	1.2	while() {
496	root	1.13	my $r = sysread $_[0][0], $_[1], $len, $ofs;
497	root	1.1	if (defined $r) {
498			$len -= $r;
499			$ofs += $r;
500			$res += $r;
501			last unless $len && $r;
502			} elsif ($! != Errno::EAGAIN) {
503			last;
504			}
505	root	1.13	last if $_[0][8] \|\| !&readable;
506	root	1.1	}
507
508			return $res;
509			}
510
511			sub READLINE {
512	root	1.13	my $irs = @_ > 1 ? $_[1] : $/;
513	root	1.1
514			while() {
515	root	1.24	if (defined $irs) {
516			my $pos = index $_[0][3], $irs;
517			if ($pos >= 0) {
518			$pos += length $irs;
519			my $res = substr $_[0][3], 0, $pos;
520			substr ($_[0][3], 0, $pos) = "";
521			return $res;
522			}
523	root	1.1	}
524	root	1.13
525			my $r = sysread $_[0][0], $_[0][3], 8192, length $_[0][3];
526	root	1.1	if (defined $r) {
527	root	1.24	return length $_[0][3] ? delete $_[0][3] : undef unless $r;
528	root	1.13	} elsif ($! != Errno::EAGAIN \|\| !&readable) {
529	root	1.24	return length $_[0][3] ? delete $_[0][3] : undef;
530	root	1.1	}
531			}
532	root	1.6	}
533
534	root	1.13	1;
535	root	1.1
536	root	1.13	=back
537	root	1.1
538			=head1 BUGS
539
540			- Perl's IO-Handle model is THE bug.
541
542			=head1 AUTHOR
543
544	root	1.13	Marc Lehmann <schmorp@schmorp.de>
545			http://home.schmorp.de/
546	root	1.1
547			=cut
548