2 # This has been taken from the 'Advanced Perl Programming' book by Sriram Srinivasan
4 # I am presuming that the code is distributed on the same basis as perl itself.
6 # I have modified it to suit my devious purposes (Dirk Koopman G1TLH)
19 use vars qw(%rd_callbacks %wt_callbacks %er_callbacks $rd_handles $wt_handles $er_handles $now %conns $noconns $blocking_supported);
24 $rd_handles = IO::Select->new();
25 $wt_handles = IO::Select->new();
26 $er_handles = IO::Select->new();
31 # Checks if blocking is supported
33 require POSIX; POSIX->import(qw(O_NONBLOCK F_SETFL F_GETFL))
35 if ($@ || $main::is_win) {
36 # print STDERR "POSIX Blocking *** NOT *** supported $@\n";
37 $blocking_supported = 0;
39 $blocking_supported = 1;
40 # print STDERR "POSIX Blocking enabled\n";
44 # import as many of these errno values as are available
46 require Errno; Errno->import(qw(EAGAIN EINPROGRESS EWOULDBLOCK));
52 my $eagain = eval {EAGAIN()};
53 my $einprogress = eval {EINPROGRESS()};
54 my $ewouldblock = eval {EWOULDBLOCK()};
58 #-----------------------------------------------------------------
59 # Generalised initializer
63 my ($pkg, $rproc) = @_;
65 my $class = $obj || $pkg;
79 dbg('connll', "Connection created ($noconns)");
80 return bless $conn, $class;
87 $conn->{eproc} = $callback;
88 set_event_handler($conn->{sock}, error => $callback) if exists $conn->{sock};
95 $conn->{rproc} = $callback;
100 return unless $blocking_supported;
102 my $flags = fcntl ($_[0], F_GETFL, 0);
104 $flags &= ~O_NONBLOCK;
106 $flags |= O_NONBLOCK;
108 fcntl ($_[0], F_SETFL, $flags);
119 $call = $pkg->{call} unless $call;
120 return undef unless $call;
121 dbg('connll', "changing $pkg->{call} to $call") if exists $pkg->{call} && $call ne $pkg->{call};
122 delete $conns{$pkg->{call}} if $pkg->{call} ne $call;
123 $pkg->{call} = $call;
124 $ref = $conns{$call} = $pkg;
125 dbg('connll', "Connection $pkg->{cnum} $call stored");
127 $ref = $conns{$call};
132 # this is only called by any dependent processes going away unexpectedly
135 my ($pkg, $pid) = @_;
137 my @pid = grep {$_->{pid} == $pid} values %conns;
138 foreach my $p (@pid) {
139 &{$p->{eproc}}($p, "$pid has gorn") if exists $p->{eproc};
144 #-----------------------------------------------------------------
147 my ($pkg, $to_host, $to_port, $rproc) = @_;
149 # Create a connection end-point object
152 $conn = $pkg->new($rproc);
154 $conn->{peerhost} = $to_host;
155 $conn->{peerport} = $to_port;
156 $conn->{sort} = 'Outgoing';
158 # Create a new internet socket
159 my $sock = IO::Socket::INET->new();
160 return undef unless $sock;
162 my $proto = getprotobyname('tcp');
163 $sock->socket(AF_INET, SOCK_STREAM, $proto) or return undef;
166 $conn->{blocking} = 0;
168 my $ip = gethostbyname($to_host);
169 # my $r = $sock->connect($to_port, $ip);
170 my $r = connect($sock, pack_sockaddr_in($to_port, $ip));
171 return undef unless $r || _err_will_block($!);
173 $conn->{sock} = $sock;
175 if ($conn->{rproc}) {
176 my $callback = sub {$conn->_rcv};
177 set_event_handler ($sock, read => $callback);
184 return if exists $conn->{disconnecting};
186 $conn->{disconnecting} = 1;
187 my $sock = delete $conn->{sock};
188 $conn->{state} = 'E';
189 $conn->{timeout}->del if $conn->{timeout};
191 # be careful to delete the correct one
193 if ($call = $conn->{call}) {
194 my $ref = $conns{$call};
195 delete $conns{$call} if $ref && $ref == $conn;
197 $call ||= 'unallocated';
198 dbg('connll', "Connection $conn->{cnum} $call disconnected");
200 unless ($main::is_win) {
201 kill 'TERM', $conn->{pid} if exists $conn->{pid};
204 # get rid of any references
206 if (ref($conn->{$_})) {
211 return unless defined($sock);
212 set_event_handler ($sock, read => undef, write => undef, error => undef);
218 my ($conn, $msg) = @_;
219 $conn->enqueue($msg);
220 $conn->_send (1); # 1 ==> flush
224 my ($conn, $msg) = @_;
225 $conn->enqueue($msg);
226 my $sock = $conn->{sock};
227 return unless defined($sock);
228 set_event_handler ($sock, write => sub {$conn->_send(0)});
233 push (@{$conn->{outqueue}}, defined $_[0] ? $_[0] : '');
237 my ($conn, $flush) = @_;
238 my $sock = $conn->{sock};
239 return unless defined($sock);
240 my $rq = $conn->{outqueue};
242 # If $flush is set, set the socket to blocking, and send all
243 # messages in the queue - return only if there's an error
244 # If $flush is 0 (deferred mode) make the socket non-blocking, and
245 # return to the event loop only after every message, or if it
246 # is likely to block in the middle of a message.
248 if ($conn->{blocking} != $flush) {
249 blocking($sock, $flush);
250 $conn->{blocking} = $flush;
252 my $offset = (exists $conn->{send_offset}) ? $conn->{send_offset} : 0;
256 my $mlth = length($msg);
257 my $bytes_to_write = $mlth - $offset;
258 my $bytes_written = 0;
259 confess("Negative Length! msg: '$msg' lth: $mlth offset: $offset") if $bytes_to_write < 0;
260 while ($bytes_to_write > 0) {
261 $bytes_written = syswrite ($sock, $msg,
262 $bytes_to_write, $offset);
263 if (!defined($bytes_written)) {
264 if (_err_will_block($!)) {
265 # Should happen only in deferred mode. Record how
266 # much we have already sent.
267 $conn->{send_offset} = $offset;
268 # Event handler should already be set, so we will
269 # be called back eventually, and will resume sending
272 &{$conn->{eproc}}($conn, $!) if exists $conn->{eproc};
274 return 0; # fail. Message remains in queue ..
276 } elsif (isdbg('raw')) {
277 my $call = $conn->{call} || 'none';
278 dbgdump('raw', "$call send $bytes_written: ", $msg);
280 $offset += $bytes_written;
281 $bytes_to_write -= $bytes_written;
283 delete $conn->{send_offset};
286 last unless $flush; # Go back to select and wait
287 # for it to fire again.
289 # Call me back if queue has not been drained.
291 set_event_handler ($sock, write => sub {$conn->_send(0)});
293 set_event_handler ($sock, write => undef);
294 if (exists $conn->{close_on_empty}) {
295 &{$conn->{eproc}}($conn, undef) if exists $conn->{eproc};
305 my $oldsock = $conn->{sock};
306 my $rc = $rd_callbacks{$oldsock};
307 my $wc = $wt_callbacks{$oldsock};
308 my $ec = $er_callbacks{$oldsock};
309 my $sock = $oldsock->new_from_fd($oldsock, "w+");
311 set_event_handler($oldsock, read=>undef, write=>undef, error=>undef);
312 $conn->{sock} = $sock;
313 set_event_handler($sock, read=>$rc, write=>$wc, error=>$ec);
318 sub _err_will_block {
319 return 0 unless $blocking_supported;
320 return ($_[0] == $eagain || $_[0] == $ewouldblock || $_[0] == $einprogress);
326 $conn->{close_on_empty} = 1;
329 #-----------------------------------------------------------------
330 # Receive side routines
333 @_ == 4 || die "Msg->new_server (myhost, myport, login_proc\n";
334 my ($pkg, $my_host, $my_port, $login_proc) = @_;
335 my $self = $pkg->new($login_proc);
337 $self->{sock} = IO::Socket::INET->new (
338 LocalAddr => $my_host,
339 LocalPort => $my_port,
343 die "Could not create socket: $! \n" unless $self->{sock};
344 set_event_handler ($self->{sock}, read => sub { $self->new_client } );
352 if ($conn->{msg} =~ /\n/) {
353 my @lines = split /\r?\n/, $conn->{msg};
354 if ($conn->{msg} =~ /\n$/) {
357 $conn->{msg} = pop @lines;
360 &{$conn->{rproc}}($conn, defined $_ ? $_ : '');
365 sub _rcv { # Complement to _send
366 my $conn = shift; # $rcv_now complement of $flush
367 # Find out how much has already been received, if at all
368 my ($msg, $offset, $bytes_to_read, $bytes_read);
369 my $sock = $conn->{sock};
370 return unless defined($sock);
373 if ($conn->{blocking}) {
375 $conn->{blocking} = 0;
377 $bytes_read = sysread ($sock, $msg, 1024, 0);
378 if (defined ($bytes_read)) {
379 if ($bytes_read > 0) {
380 $conn->{msg} .= $msg;
382 my $call = $conn->{call} || 'none';
383 dbgdump('raw', "$call read $bytes_read: ", $msg);
387 if (_err_will_block($!)) {
395 if (defined $bytes_read && $bytes_read == 0) {
396 &{$conn->{eproc}}($conn, $!) if exists $conn->{eproc};
399 $conn->dequeue if exists $conn->{msg};
404 my $server_conn = shift;
405 my $sock = $server_conn->{sock}->accept();
407 my $conn = $server_conn->new($server_conn->{rproc});
408 $conn->{sock} = $sock;
410 $conn->{blocking} = 0;
411 my ($rproc, $eproc) = &{$server_conn->{rproc}} ($conn, $conn->{peerhost} = $sock->peerhost(), $conn->{peerport} = $sock->peerport());
412 $conn->{sort} = 'Incoming';
414 $conn->{eproc} = $eproc;
415 set_event_handler ($sock, error => $eproc);
418 $conn->{rproc} = $rproc;
419 my $callback = sub {$conn->_rcv};
420 set_event_handler ($sock, read => $callback);
421 } else { # Login failed
422 &{$conn->{eproc}}($conn, undef) if exists $conn->{eproc};
426 dbg('err', "Msg: error on accept ($!)");
433 set_event_handler ($conn->{sock}, read => undef, write => undef, error => undef );
434 $conn->{sock}->close;
437 # close all clients (this is for forking really)
438 sub close_all_clients
440 foreach my $conn (values %conns) {
446 #----------------------------------------------------
447 # Event loop routines used by both client and server
449 sub set_event_handler {
450 shift unless ref($_[0]); # shift if first arg is package name
451 my ($handle, %args) = @_;
453 if (exists $args{'write'}) {
454 $callback = $args{'write'};
456 $wt_callbacks{$handle} = $callback;
457 $wt_handles->add($handle);
459 delete $wt_callbacks{$handle};
460 $wt_handles->remove($handle);
463 if (exists $args{'read'}) {
464 $callback = $args{'read'};
466 $rd_callbacks{$handle} = $callback;
467 $rd_handles->add($handle);
469 delete $rd_callbacks{$handle};
470 $rd_handles->remove($handle);
473 if (exists $args{'error'}) {
474 $callback = $args{'error'};
476 $er_callbacks{$handle} = $callback;
477 $er_handles->add($handle);
479 delete $er_callbacks{$handle};
480 $er_handles->remove($handle);
486 my ($pkg, $loop_count, $timeout) = @_; # event_loop(1) to process events once
487 my ($conn, $r, $w, $e, $rset, $wset, $eset);
490 # Quit the loop if no handles left to process
491 last unless ($rd_handles->count() || $wt_handles->count());
493 ($rset, $wset, $eset) = IO::Select->select($rd_handles, $wt_handles, $er_handles, $timeout);
495 foreach $e (@$eset) {
496 &{$er_callbacks{$e}}($e) if exists $er_callbacks{$e};
498 foreach $r (@$rset) {
499 &{$rd_callbacks{$r}}($r) if exists $rd_callbacks{$r};
501 foreach $w (@$wset) {
502 &{$wt_callbacks{$w}}($w) if exists $wt_callbacks{$w};
507 if (defined($loop_count)) {
508 last unless --$loop_count;
515 my ($pkg, $interval) = @_;
517 while (time - $now < $interval) {
518 $pkg->event_loop(10, 0.01);
525 my $call = $conn->{call} || 'unallocated';
526 my $host = $conn->{peerhost} || '';
527 my $port = $conn->{peerport} || '';
528 dbg('connll', "Connection $conn->{cnum} $call [$host $port] being destroyed");