AnyEvent-MP/MP/Kernel.pm

=head1 NAME

AnyEvent::MP::Kernel - the actual message passing kernel

=head1 SYNOPSIS

   use AnyEvent::MP::Kernel;

=head1 DESCRIPTION

This module provides most of the basic functionality of AnyEvent::MP,
exposed through higher level interfaces such as L<AnyEvent::MP> and
L<Coro::MP>.

This module is mainly of interest when knowledge about connectivity,
connected nodes etc. are needed.

=head1 GLOBALS AND FUNCTIONS

=over 4

=cut

package AnyEvent::MP::Kernel;

use common::sense;
use POSIX ();
use Carp ();
use MIME::Base64 ();

use AE ();

use AnyEvent::MP::Node;
use AnyEvent::MP::Transport;

use base "Exporter";

our $VERSION = '0.8';
our @EXPORT = qw(
   %NODE %PORT %PORT_DATA $UNIQ $RUNIQ $ID
   add_node load_func snd_to_func snd_on eval_on

   NODE $NODE node_of snd kil
   port_is_local
   resolve_node initialise_node
   known_nodes up_nodes mon_nodes node_is_known node_is_up
);

our $DEFAULT_PORT = "4040";

our $CONNECT_INTERVAL =  2; # new connect every 2s, at least
our $NETWORK_LATENCY  =  3; # activity timeout
our $MONITOR_TIMEOUT  = 15; # fail monitoring after this time

=item $AnyEvent::MP::Kernel::WARN->($level, $msg)

This value is called with an error or warning message, when e.g. a connection
could not be created, authorisation failed and so on.

C<$level> sould be C<0> for messages ot be logged always, C<1> for
unexpected messages and errors, C<2> for warnings, C<7> for messages about
node connectivity and services, C<8> for debugging messages and C<9> for
tracing messages.

The default simply logs the message to STDERR.

=cut

our $WARN = sub {
   my ($level, $msg) = @_;

   $msg =~ s/\n$//;

   printf STDERR "%s <%d> %s\n",
          (POSIX::strftime "%Y-%m-%d %H:%M:%S", localtime time),
          $level,
          $msg;
};

sub load_func($) {
   my $func = $_[0];

   unless (defined &$func) {
      my $pkg = $func;
      do {
         $pkg =~ s/::[^:]+$//
            or return sub { die "unable to resolve '$func'" };
         eval "require $pkg";
      } until defined &$func;
   }

   \&$func
}

sub nonce($) {
   my $nonce;

   if (open my $fh, "</dev/urandom") {
      sysread $fh, $nonce, $_[0];
   } else {
      # shit...
      our $nonce_init;
      unless ($nonce_init++) {
         srand time ^ $$ ^ unpack "%L*", qx"ps -edalf" . qx"ipconfig /all";
      }

      $nonce = join "", map +(chr rand 256), 1 .. $_[0]
   }

   $nonce
}

sub alnumbits($) {
   my $data = $_[0];

   if (eval "use Math::GMP 2.05; 1") {
      $data = Math::GMP::get_str_gmp (
                  (Math::GMP::new_from_scalar_with_base (+(unpack "H*", $data), 16)),
                  62
              );
   } else {
      $data = MIME::Base64::encode_base64 $data, "";
      $data =~ s/=//;
      $data =~ s/\//s/g;
      $data =~ s/\+/p/g;
   }

   $data
}

sub gen_uniq {
   alnumbits pack "wNa*", $$, time, nonce 2
}

=item $AnyEvent::MP::Kernel::PUBLIC

A boolean indicating whether this is a public node, which can create and
accept direct connections from other nodes.

=cut

our $CONFIG; # this node's configuration

our $RUNIQ  = alnumbits nonce 16;; # remote uniq value
our $UNIQ   = gen_uniq; # per-process/node unique cookie
our $NODE   = "anon/$RUNIQ";
our $ID     = "a";

our %NODE; # node id to transport mapping, or "undef", for local node
our (%PORT, %PORT_DATA); # local ports

our %RMON; # local ports monitored by remote nodes ($RMON{nodeid}{portid} == cb)
our %LMON; # monitored _local_ ports

our %LISTENER;
our $LISTENER; # our listeners, as arrayref

our $SRCNODE; # holds the sending node during _inject

sub NODE() {
   $NODE
}

sub node_of($) {
   my ($node, undef) = split /#/, $_[0], 2;

   $node
}

BEGIN {
   *TRACE = $ENV{PERL_ANYEVENT_MP_TRACE}
      ? sub () { 1 }
      : sub () { 0 };
}

sub _inject {
   warn "RCV $SRCNODE->{id} -> @_\n" if TRACE && @_;#d#
   &{ $PORT{+shift} or return };
}

# this function adds a node-ref, so you can send stuff to it
# it is basically the central routing component.
sub add_node {
   my ($node) = @_;

   $NODE{$node} ||= new AnyEvent::MP::Node::Direct $node
}

sub snd(@) {
   my ($nodeid, $portid) = split /#/, shift, 2;

   warn "SND $nodeid <- $portid @_\n" if TRACE;#d#

   ($NODE{$nodeid} || add_node $nodeid)
      ->{send} (["$portid", @_]);
}

=item $is_local = port_is_local $port

Returns true iff the port is a local port.

=cut

sub port_is_local($) {
   my ($nodeid, undef) = split /#/, $_[0], 2;

   $NODE{$nodeid} == $NODE{""}
}

=item snd_to_func $node, $func, @args

Expects a node ID and a name of a function. Asynchronously tries to call
this function with the given arguments on that node.

This function can be used to implement C<spawn>-like interfaces.

=cut

sub snd_to_func($$;@) {
   my $nodeid = shift;

   ($NODE{$nodeid} || add_node $nodeid)
      ->send (["", @_]);
}

=item snd_on $node, @msg

Executes C<snd> with the given C<@msg> (which must include the destination
port) on the given node.

=cut

sub snd_on($@) {
   my $node = shift;
   snd $node, snd => @_;
}

=item eval_on $node, $string

Evaluates the given string as Perl expression on the given node.

=cut

sub eval_on($@) {
   my $node = shift;
   snd $node, eval => @_;
}

sub kil(@) {
   my ($nodeid, $portid) = split /#/, shift, 2;

   length $portid
      or Carp::croak "$nodeid#$portid: killing a node port is not allowed, caught";

   ($NODE{$nodeid} || add_node $nodeid)
      ->kill ("$portid", @_);
}

sub _nodename {
   require POSIX;
   (POSIX::uname ())[1]
}

sub _resolve($) {
   my ($nodeid) = @_;

   my $cv = AE::cv;
   my @res;

   $cv->begin (sub {
      my %seen;
      my @refs;
      for (sort { $a->[0] <=> $b->[0] } @res) {
         push @refs, $_->[1] unless $seen{$_->[1]}++
      }
      shift->send (@refs);
   });

   $nodeid = $DEFAULT_PORT unless length $nodeid;

   my $idx;
   for my $t (split /,/, $nodeid) {
      my $pri = ++$idx;

      $t = length $t ? _nodename . ":$t" : _nodename
         if $t =~ /^\d*$/;
      
      my ($host, $port) = AnyEvent::Socket::parse_hostport $t, "aemp=$DEFAULT_PORT"
         or Carp::croak "$t: unparsable transport descriptor";

      $cv->begin;
      AnyEvent::Socket::resolve_sockaddr $host, $port, "tcp", 0, undef, sub {
         for (@_) {
            my ($service, $host) = AnyEvent::Socket::unpack_sockaddr $_->[3];
            push @res, [
               $pri += 1e-5,
               AnyEvent::Socket::format_hostport AnyEvent::Socket::format_address $host, $service
            ];
         }
         $cv->end;
      };
   }

   $cv->end;

   $cv
}

sub initialise_node(;$%) {
   my ($profile) = @_;

   $profile = _nodename
      unless defined $profile;

   $CONFIG = AnyEvent::MP::Config::find_profile $profile;
   $NODE = exists $CONFIG->{nodeid} ? $CONFIG->{nodeid}
         : $profile eq "anon/"      ? $NODE
                                    : $profile;

   $NODE{$NODE} = $NODE{""};
   $NODE{$NODE}{id} = $NODE;

   my $seeds = $CONFIG->{seeds};
   my $binds = $CONFIG->{binds};

   $binds ||= [$NODE];

   $WARN->(8, "node $NODE starting up.");

   for (map _resolve $_, @$binds) {
      for my $bind ($_->recv) {
         my ($host, $port) = AnyEvent::Socket::parse_hostport $bind
            or Carp::croak "$bind: unparsable local bind address";

         $LISTENER{$bind} = AnyEvent::MP::Transport::mp_server $host, $port;
         push @$LISTENER, $bind;
      }
   }

   # the global service is mandatory currently
   require AnyEvent::MP::Global;

   # connect to all seednodes
   AnyEvent::MP::Global::set_seeds (map $_->recv, map _resolve $_, @$seeds);

   for (@{ $CONFIG->{services} }) {
      if (s/::$//) {
         eval "require $_";
         die $@ if $@;
      } else {
         (load_func $_)->();
      }
   }
}

#############################################################################
# node monitoring and info

sub _uniq_nodes {
   my %node;

   @node{values %NODE} = values %NODE;

   values %node;
}

sub _public_nodes {
   &_uniq_nodes
}

=item node_is_known $nodeid

Returns true iff the given node is currently known to the system.

=cut

sub node_is_known($) {
   exists $NODE{$_[0]}
}

=item node_is_up $nodeid

Returns true if the given node is "up", that is, the kernel thinks it has
a working connection to it.

If the node is known but not currently connected, returns C<0>. If the
node is not known, returns C<undef>.

=cut

sub node_is_up($) {
   ($NODE{$_[0]} or return)->{transport}
      ? 1 : 0
}

=item known_nodes

Returns the node IDs of all public nodes connected to this node, including
itself.

=cut

sub known_nodes {
   map $_->{id}, _public_nodes
}

=item up_nodes

Return the node IDs of all public nodes that are currently connected
(excluding the node itself).

=cut

sub up_nodes {
   map $_->{id}, grep $_->{transport}, _public_nodes
}

=item $guard = mon_nodes $callback->($nodeid, $is_up, @reason)

Registers a callback that is called each time a node goes up (connection
is established) or down (connection is lost).

Node up messages can only be followed by node down messages for the same
node, and vice versa.

The function returns an optional guard which can be used to de-register
the monitoring callback again.

=cut

our %MON_NODES;

sub mon_nodes($) {
   my ($cb) = @_;

   $MON_NODES{$cb+0} = $cb;

   wantarray && AnyEvent::Util::guard { delete $MON_NODES{$cb+0} }
}

sub _inject_nodeevent($$;@) {
   my ($node, $up, @reason) = @_;

   for my $cb (values %MON_NODES) {
      eval { $cb->($node->{id}, $up, @reason); 1 }
         or $WARN->(1, $@);
   }

   $WARN->(7, "$node->{id} is " . ($up ? "up" : "down") . " (@reason)");
}

#############################################################################
# self node code

our %node_req = (
   # internal services

   # monitoring
   mon0 => sub { # disable monitoring
      my $portid = shift;
      my $node   = $SRCNODE;
      $NODE{""}->unmonitor ($portid, delete $node->{rmon}{$portid});
   },
   mon1 => sub { # enable monitoring
      my $portid = shift;
      my $node   = $SRCNODE;
      $NODE{""}->monitor ($portid, $node->{rmon}{$portid} = sub {
         $node->send (["", kil => $portid, @_]);
      });
   },
   kil => sub {
      my $cbs = delete $SRCNODE->{lmon}{+shift}
         or return;

      $_->(@_) for @$cbs;
   },

   # "public" services - not actually public

   # relay message to another node / generic echo
   snd => \&snd,
   snd_multi => sub {
      snd @$_ for @_
   },

   # informational
   info => sub {
      snd @_, $NODE;
   },
   known_nodes => sub {
      snd @_, known_nodes;
   },
   up_nodes => sub {
      snd @_, up_nodes;
   },

   # random garbage
   eval => sub {
      my @res = eval shift;
      snd @_, "$@", @res if @_;
   },
   time => sub {
      snd @_, AE::time;
   },
   devnull => sub {
      #
   },
   "" => sub {
      # empty messages are sent by monitoring
   },
);

$NODE{""} = $NODE{$NODE} = new AnyEvent::MP::Node::Self $NODE;
$PORT{""} = sub {
   my $tag = shift;
   eval { &{ $node_req{$tag} ||= load_func $tag } };
   $WARN->(2, "error processing node message: $@") if $@;
};

=back

=head1 SEE ALSO

L<AnyEvent::MP>.

=head1 AUTHOR

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

=cut

1

Revision:	1.22
Committed:	Thu Aug 27 22:21:09 2009 UTC (14 years, 9 months ago) by root
Branch:	MAIN
Changes since 1.21:	+1 -1 lines
Log Message:	* empty log message *
#	Content
1	=head1 NAME
2
3	AnyEvent::MP::Kernel - the actual message passing kernel
4
5	=head1 SYNOPSIS
6
7	use AnyEvent::MP::Kernel;
8
9	=head1 DESCRIPTION
10
11	This module provides most of the basic functionality of AnyEvent::MP,
12	exposed through higher level interfaces such as L<AnyEvent::MP> and
13	L<Coro::MP>.
14
15	This module is mainly of interest when knowledge about connectivity,
16	connected nodes etc. are needed.
17
18	=head1 GLOBALS AND FUNCTIONS
19
20	=over 4
21
22	=cut
23
24	package AnyEvent::MP::Kernel;
25
26	use common::sense;
27	use POSIX ();
28	use Carp ();
29	use MIME::Base64 ();
30
31	use AE ();
32
33	use AnyEvent::MP::Node;
34	use AnyEvent::MP::Transport;
35
36	use base "Exporter";
37
38	our $VERSION = '0.8';
39	our @EXPORT = qw(
40	%NODE %PORT %PORT_DATA $UNIQ $RUNIQ $ID
41	add_node load_func snd_to_func snd_on eval_on
42
43	NODE $NODE node_of snd kil
44	port_is_local
45	resolve_node initialise_node
46	known_nodes up_nodes mon_nodes node_is_known node_is_up
47	);
48
49	our $DEFAULT_PORT = "4040";
50
51	our $CONNECT_INTERVAL = 2; # new connect every 2s, at least
52	our $NETWORK_LATENCY = 3; # activity timeout
53	our $MONITOR_TIMEOUT = 15; # fail monitoring after this time
54
55	=item $AnyEvent::MP::Kernel::WARN->($level, $msg)
56
57	This value is called with an error or warning message, when e.g. a connection
58	could not be created, authorisation failed and so on.
59
60	C<$level> sould be C<0> for messages ot be logged always, C<1> for
61	unexpected messages and errors, C<2> for warnings, C<7> for messages about
62	node connectivity and services, C<8> for debugging messages and C<9> for
63	tracing messages.
64
65	The default simply logs the message to STDERR.
66
67	=cut
68
69	our $WARN = sub {
70	my ($level, $msg) = @_;
71
72	$msg =~ s/\n$//;
73
74	printf STDERR "%s <%d> %s\n",
75	(POSIX::strftime "%Y-%m-%d %H:%M:%S", localtime time),
76	$level,
77	$msg;
78	};
79
80	sub load_func($) {
81	my $func = $_[0];
82
83	unless (defined &$func) {
84	my $pkg = $func;
85	do {
86	$pkg =~ s/::[^:]+$//
87	or return sub { die "unable to resolve '$func'" };
88	eval "require $pkg";
89	} until defined &$func;
90	}
91
92	\&$func
93	}
94
95	sub nonce($) {
96	my $nonce;
97
98	if (open my $fh, "</dev/urandom") {
99	sysread $fh, $nonce, $_[0];
100	} else {
101	# shit...
102	our $nonce_init;
103	unless ($nonce_init++) {
104	srand time ^ $$ ^ unpack "%L*", qx"ps -edalf" . qx"ipconfig /all";
105	}
106
107	$nonce = join "", map +(chr rand 256), 1 .. $_[0]
108	}
109
110	$nonce
111	}
112
113	sub alnumbits($) {
114	my $data = $_[0];
115
116	if (eval "use Math::GMP 2.05; 1") {
117	$data = Math::GMP::get_str_gmp (
118	(Math::GMP::new_from_scalar_with_base (+(unpack "H*", $data), 16)),
119	62
120	);
121	} else {
122	$data = MIME::Base64::encode_base64 $data, "";
123	$data =~ s/=//;
124	$data =~ s/\//s/g;
125	$data =~ s/\+/p/g;
126	}
127
128	$data
129	}
130
131	sub gen_uniq {
132	alnumbits pack "wNa*", $$, time, nonce 2
133	}
134
135	=item $AnyEvent::MP::Kernel::PUBLIC
136
137	A boolean indicating whether this is a public node, which can create and
138	accept direct connections from other nodes.
139
140	=cut
141
142	our $CONFIG; # this node's configuration
143
144	our $RUNIQ = alnumbits nonce 16;; # remote uniq value
145	our $UNIQ = gen_uniq; # per-process/node unique cookie
146	our $NODE = "anon/$RUNIQ";
147	our $ID = "a";
148
149	our %NODE; # node id to transport mapping, or "undef", for local node
150	our (%PORT, %PORT_DATA); # local ports
151
152	our %RMON; # local ports monitored by remote nodes ($RMON{nodeid}{portid} == cb)
153	our %LMON; # monitored _local_ ports
154
155	our %LISTENER;
156	our $LISTENER; # our listeners, as arrayref
157
158	our $SRCNODE; # holds the sending node during _inject
159
160	sub NODE() {
161	$NODE
162	}
163
164	sub node_of($) {
165	my ($node, undef) = split /#/, $_[0], 2;
166
167	$node
168	}
169
170	BEGIN {
171	*TRACE = $ENV{PERL_ANYEVENT_MP_TRACE}
172	? sub () { 1 }
173	: sub () { 0 };
174	}
175
176	sub _inject {
177	warn "RCV $SRCNODE->{id} -> @_\n" if TRACE && @_;#d#
178	&{ $PORT{+shift} or return };
179	}
180
181	# this function adds a node-ref, so you can send stuff to it
182	# it is basically the central routing component.
183	sub add_node {
184	my ($node) = @_;
185
186	$NODE{$node} \|\|= new AnyEvent::MP::Node::Direct $node
187	}
188
189	sub snd(@) {
190	my ($nodeid, $portid) = split /#/, shift, 2;
191
192	warn "SND $nodeid <- $portid @_\n" if TRACE;#d#
193
194	($NODE{$nodeid} \|\| add_node $nodeid)
195	->{send} (["$portid", @_]);
196	}
197
198	=item $is_local = port_is_local $port
199
200	Returns true iff the port is a local port.
201
202	=cut
203
204	sub port_is_local($) {
205	my ($nodeid, undef) = split /#/, $_[0], 2;
206
207	$NODE{$nodeid} == $NODE{""}
208	}
209
210	=item snd_to_func $node, $func, @args
211
212	Expects a node ID and a name of a function. Asynchronously tries to call
213	this function with the given arguments on that node.
214
215	This function can be used to implement C<spawn>-like interfaces.
216
217	=cut
218
219	sub snd_to_func($$;@) {
220	my $nodeid = shift;
221
222	($NODE{$nodeid} \|\| add_node $nodeid)
223	->send (["", @_]);
224	}
225
226	=item snd_on $node, @msg
227
228	Executes C<snd> with the given C<@msg> (which must include the destination
229	port) on the given node.
230
231	=cut
232
233	sub snd_on($@) {
234	my $node = shift;
235	snd $node, snd => @_;
236	}
237
238	=item eval_on $node, $string
239
240	Evaluates the given string as Perl expression on the given node.
241
242	=cut
243
244	sub eval_on($@) {
245	my $node = shift;
246	snd $node, eval => @_;
247	}
248
249	sub kil(@) {
250	my ($nodeid, $portid) = split /#/, shift, 2;
251
252	length $portid
253	or Carp::croak "$nodeid#$portid: killing a node port is not allowed, caught";
254
255	($NODE{$nodeid} \|\| add_node $nodeid)
256	->kill ("$portid", @_);
257	}
258
259	sub _nodename {
260	require POSIX;
261	(POSIX::uname ())[1]
262	}
263
264	sub _resolve($) {
265	my ($nodeid) = @_;
266
267	my $cv = AE::cv;
268	my @res;
269
270	$cv->begin (sub {
271	my %seen;
272	my @refs;
273	for (sort { $a->[0] <=> $b->[0] } @res) {
274	push @refs, $_->[1] unless $seen{$_->[1]}++
275	}
276	shift->send (@refs);
277	});
278
279	$nodeid = $DEFAULT_PORT unless length $nodeid;
280
281	my $idx;
282	for my $t (split /,/, $nodeid) {
283	my $pri = ++$idx;
284
285	$t = length $t ? _nodename . ":$t" : _nodename
286	if $t =~ /^\d*$/;
287
288	my ($host, $port) = AnyEvent::Socket::parse_hostport $t, "aemp=$DEFAULT_PORT"
289	or Carp::croak "$t: unparsable transport descriptor";
290
291	$cv->begin;
292	AnyEvent::Socket::resolve_sockaddr $host, $port, "tcp", 0, undef, sub {
293	for (@_) {
294	my ($service, $host) = AnyEvent::Socket::unpack_sockaddr $_->[3];
295	push @res, [
296	$pri += 1e-5,
297	AnyEvent::Socket::format_hostport AnyEvent::Socket::format_address $host, $service
298	];
299	}
300	$cv->end;
301	};
302	}
303
304	$cv->end;
305
306	$cv
307	}
308
309	sub initialise_node(;$%) {
310	my ($profile) = @_;
311
312	$profile = _nodename
313	unless defined $profile;
314
315	$CONFIG = AnyEvent::MP::Config::find_profile $profile;
316	$NODE = exists $CONFIG->{nodeid} ? $CONFIG->{nodeid}
317	: $profile eq "anon/" ? $NODE
318	: $profile;
319
320	$NODE{$NODE} = $NODE{""};
321	$NODE{$NODE}{id} = $NODE;
322
323	my $seeds = $CONFIG->{seeds};
324	my $binds = $CONFIG->{binds};
325
326	$binds \|\|= [$NODE];
327
328	$WARN->(8, "node $NODE starting up.");
329
330	for (map _resolve $_, @$binds) {
331	for my $bind ($_->recv) {
332	my ($host, $port) = AnyEvent::Socket::parse_hostport $bind
333	or Carp::croak "$bind: unparsable local bind address";
334
335	$LISTENER{$bind} = AnyEvent::MP::Transport::mp_server $host, $port;
336	push @$LISTENER, $bind;
337	}
338	}
339
340	# the global service is mandatory currently
341	require AnyEvent::MP::Global;
342
343	# connect to all seednodes
344	AnyEvent::MP::Global::set_seeds (map $_->recv, map _resolve $_, @$seeds);
345
346	for (@{ $CONFIG->{services} }) {
347	if (s/::$//) {
348	eval "require $_";
349	die $@ if $@;
350	} else {
351	(load_func $_)->();
352	}
353	}
354	}
355
356	#############################################################################
357	# node monitoring and info
358
359	sub _uniq_nodes {
360	my %node;
361
362	@node{values %NODE} = values %NODE;
363
364	values %node;
365	}
366
367	sub _public_nodes {
368	&_uniq_nodes
369	}
370
371	=item node_is_known $nodeid
372
373	Returns true iff the given node is currently known to the system.
374
375	=cut
376
377	sub node_is_known($) {
378	exists $NODE{$_[0]}
379	}
380
381	=item node_is_up $nodeid
382
383	Returns true if the given node is "up", that is, the kernel thinks it has
384	a working connection to it.
385
386	If the node is known but not currently connected, returns C<0>. If the
387	node is not known, returns C<undef>.
388
389	=cut
390
391	sub node_is_up($) {
392	($NODE{$_[0]} or return)->{transport}
393	? 1 : 0
394	}
395
396	=item known_nodes
397
398	Returns the node IDs of all public nodes connected to this node, including
399	itself.
400
401	=cut
402
403	sub known_nodes {
404	map $_->{id}, _public_nodes
405	}
406
407	=item up_nodes
408
409	Return the node IDs of all public nodes that are currently connected
410	(excluding the node itself).
411
412	=cut
413
414	sub up_nodes {
415	map $_->{id}, grep $_->{transport}, _public_nodes
416	}
417
418	=item $guard = mon_nodes $callback->($nodeid, $is_up, @reason)
419
420	Registers a callback that is called each time a node goes up (connection
421	is established) or down (connection is lost).
422
423	Node up messages can only be followed by node down messages for the same
424	node, and vice versa.
425
426	The function returns an optional guard which can be used to de-register
427	the monitoring callback again.
428
429	=cut
430
431	our %MON_NODES;
432
433	sub mon_nodes($) {
434	my ($cb) = @_;
435
436	$MON_NODES{$cb+0} = $cb;
437
438	wantarray && AnyEvent::Util::guard { delete $MON_NODES{$cb+0} }
439	}
440
441	sub _inject_nodeevent($$;@) {
442	my ($node, $up, @reason) = @_;
443
444	for my $cb (values %MON_NODES) {
445	eval { $cb->($node->{id}, $up, @reason); 1 }
446	or $WARN->(1, $@);
447	}
448
449	$WARN->(7, "$node->{id} is " . ($up ? "up" : "down") . " (@reason)");
450	}
451
452	#############################################################################
453	# self node code
454
455	our %node_req = (
456	# internal services
457
458	# monitoring
459	mon0 => sub { # disable monitoring
460	my $portid = shift;
461	my $node = $SRCNODE;
462	$NODE{""}->unmonitor ($portid, delete $node->{rmon}{$portid});
463	},
464	mon1 => sub { # enable monitoring
465	my $portid = shift;
466	my $node = $SRCNODE;
467	$NODE{""}->monitor ($portid, $node->{rmon}{$portid} = sub {
468	$node->send (["", kil => $portid, @_]);
469	});
470	},
471	kil => sub {
472	my $cbs = delete $SRCNODE->{lmon}{+shift}
473	or return;
474
475	$_->(@_) for @$cbs;
476	},
477
478	# "public" services - not actually public
479
480	# relay message to another node / generic echo
481	snd => \&snd,
482	snd_multi => sub {
483	snd @$_ for @_
484	},
485
486	# informational
487	info => sub {
488	snd @_, $NODE;
489	},
490	known_nodes => sub {
491	snd @_, known_nodes;
492	},
493	up_nodes => sub {
494	snd @_, up_nodes;
495	},
496
497	# random garbage
498	eval => sub {
499	my @res = eval shift;
500	snd @_, "$@", @res if @_;
501	},
502	time => sub {
503	snd @_, AE::time;
504	},
505	devnull => sub {
506	#
507	},
508	"" => sub {
509	# empty messages are sent by monitoring
510	},
511	);
512
513	$NODE{""} = $NODE{$NODE} = new AnyEvent::MP::Node::Self $NODE;
514	$PORT{""} = sub {
515	my $tag = shift;
516	eval { &{ $node_req{$tag} \|\|= load_func $tag } };
517	$WARN->(2, "error processing node message: $@") if $@;
518	};
519
520	=back
521
522	=head1 SEE ALSO
523
524	L<AnyEvent::MP>.
525
526	=head1 AUTHOR
527
528	Marc Lehmann <schmorp@schmorp.de>
529	http://home.schmorp.de/
530
531	=cut
532
533	1
534