use Scalar::Util qw(blessed);
use PublicInbox::Syscall qw(:epoll);
use PublicInbox::Tmpfile;
-use Errno qw(EAGAIN EINVAL);
+use Errno qw(EAGAIN EINVAL ECHILD EINTR);
use Carp qw(carp croak);
-our @EXPORT_OK = qw(now msg_more dwaitpid add_timer add_uniq_timer);
+our @EXPORT_OK = qw(now msg_more awaitpid add_timer add_uniq_timer);
my %Stack;
my $nextq; # queue for next_tick
-my $wait_pids; # list of [ pid, callback, callback_arg ]
-my $EXPMAP; # fd -> idle_time
-our $EXPTIME = 180; # 3 minutes
-my ($reap_armed);
+my $AWAIT_PIDS; # pid => [ $callback, @args ]
+my $reap_armed;
my $ToClose; # sockets to close when event loop is done
our (
%DescriptorMap, # fd (num) -> PublicInbox::DS object
$Epoll, # Global epoll fd (or DSKQXS ref)
- $_io, # IO::Handle for Epoll
+ $ep_io, # IO::Handle for Epoll
$PostLoopCallback, # subref to call at the end of each loop, if defined (global)
# we may be iterating inside one of these on our stack
my @q = delete @Stack{keys %Stack};
for my $q (@q) { @$q = () }
- $EXPMAP = undef;
- $wait_pids = $nextq = $ToClose = undef;
- $_io = undef; # closes real $Epoll FD
+ $AWAIT_PIDS = $nextq = $ToClose = undef;
+ $ep_io = undef; # closes real $Epoll FD
$Epoll = undef; # may call DSKQXS::DESTROY
- } while (@Timers || keys(%Stack) || $nextq || $wait_pids ||
+ } while (@Timers || keys(%Stack) || $nextq || $AWAIT_PIDS ||
$ToClose || keys(%DescriptorMap) ||
$PostLoopCallback || keys(%UniqTimer));
$UniqTimer{$_[0]} //= _add_named_timer(@_);
}
-# keeping this around in case we support other FD types for now,
-# epoll_create1(EPOLL_CLOEXEC) requires Linux 2.6.27+...
-sub set_cloexec ($) {
- my ($fd) = @_;
-
- open($_io, '+<&=', $fd) or return;
- defined(my $fl = fcntl($_io, F_GETFD, 0)) or return;
- fcntl($_io, F_SETFD, $fl | FD_CLOEXEC);
-}
-
# caller sets return value to $Epoll
-sub _InitPoller
-{
- if (PublicInbox::Syscall::epoll_defined()) {
- my $fd = epoll_create();
- set_cloexec($fd) if (defined($fd) && $fd >= 0);
- $fd;
- } else {
- my $cls;
- for (qw(DSKQXS DSPoll)) {
- $cls = "PublicInbox::$_";
- last if eval "require $cls";
- }
- $cls->import(qw(epoll_ctl epoll_wait));
- $cls->new;
- }
+sub _InitPoller () {
+ if (defined $PublicInbox::Syscall::SYS_epoll_create) {
+ my $fd = epoll_create();
+ die "epoll_create: $!" if $fd < 0;
+ open($ep_io, '+<&=', $fd) or return;
+ fcntl($ep_io, F_SETFD, FD_CLOEXEC);
+ $fd;
+ } else {
+ my $cls;
+ for (qw(DSKQXS DSPoll)) {
+ $cls = "PublicInbox::$_";
+ last if eval "require $cls";
+ }
+ $cls->import(qw(epoll_ctl epoll_wait));
+ $cls->new;
+ }
}
sub now () { clock_gettime(CLOCK_MONOTONIC) }
$oldset;
}
-# We can't use waitpid(-1) safely here since it can hit ``, system(),
-# and other things. So we scan the $wait_pids list, which is hopefully
-# not too big. We keep $wait_pids small by not calling dwaitpid()
-# until we've hit EOF when reading the stdout of the child.
+sub await_cb ($;@) {
+ my ($pid, @cb_args) = @_;
+ my $cb = shift @cb_args or return;
+ eval { $cb->($pid, @cb_args) };
+ warn "E: awaitpid($pid): $@" if $@;
+}
+# This relies on our Perl process is single-threaded, or at least
+# no threads are spawning and waiting on processes (``, system(), etc...)
+# Threads are officially discouraged by the Perl5 team, and I expect
+# that to remain the case.
sub reap_pids {
$reap_armed = undef;
- my $tmp = $wait_pids or return;
- $wait_pids = undef;
- $Stack{reap_runq} = $tmp;
my $oldset = block_signals();
- foreach my $ary (@$tmp) {
- my ($pid, $cb, $arg) = @$ary;
- my $ret = waitpid($pid, WNOHANG);
- if ($ret == 0) {
- push @$wait_pids, $ary; # autovivifies @$wait_pids
- } elsif ($ret == $pid) {
- if ($cb) {
- eval { $cb->($arg, $pid) };
- warn "E: dwaitpid($pid) in_loop: $@" if $@;
- }
+ while (1) {
+ my $pid = waitpid(-1, WNOHANG) // last;
+ last if $pid <= 0;
+ if (defined(my $cb_args = delete $AWAIT_PIDS->{$pid})) {
+ await_cb($pid, @$cb_args) if $cb_args;
} else {
- warn "waitpid($pid, WNOHANG) = $ret, \$!=$!, \$?=$?";
+ warn "W: reaped unknown PID=$pid: \$?=$?\n";
}
}
sig_setmask($oldset);
- delete $Stack{reap_runq};
}
# reentrant SIGCHLD handler (since reap_pids is not reentrant)
$ToClose = undef; # will be autovivified on push
@$close_now = map { fileno($_) } @$close_now;
- # order matters, destroy expiry times, first:
- delete @$EXPMAP{@$close_now};
-
# ->DESTROY methods may populate ToClose
delete @DescriptorMap{@$close_now};
}
$DescriptorMap{$fd} = $self;
}
+# for IMAP, NNTP, and POP3 which greet clients upon connect
+sub greet {
+ my ($self, $sock) = @_;
+ my $ev = EPOLLIN;
+ my $wbuf;
+ if ($sock->can('accept_SSL') && !$sock->accept_SSL) {
+ return CORE::close($sock) if $! != EAGAIN;
+ $ev = PublicInbox::TLS::epollbit() or return CORE::close($sock);
+ $wbuf = [ \&accept_tls_step, $self->can('do_greet')];
+ }
+ new($self, $sock, $ev | EPOLLONESHOT);
+ if ($wbuf) {
+ $self->{wbuf} = $wbuf;
+ } else {
+ $self->do_greet;
+ }
+ $self;
+}
#####################################################################
### I N S T A N C E M E T H O D S
$self->close;
}
-# n.b.: use ->write/->read for this buffer to allow compatibility with
-# PerlIO::mmap or PerlIO::scalar if needed
sub tmpio ($$$) {
my ($self, $bref, $off) = @_;
my $fh = tmpfile('wbuf', $self->{sock}, O_APPEND) or
return drop($self, "tmpfile $!");
$fh->autoflush(1);
my $len = length($$bref) - $off;
- print $fh substr($$bref, $off, $len) or
+ my $n = syswrite($fh, $$bref, $len, $off) //
return drop($self, "write ($len): $!");
+ $n == $len or return drop($self, "wrote $n < $len bytes");
[ $fh, 0 ] # [1] = offset, [2] = length, not set by us
}
}
}
-sub dwaitpid ($;$$) {
- my ($pid, $cb, $arg) = @_;
- if ($in_loop) {
- push @$wait_pids, [ $pid, $cb, $arg ];
- # We could've just missed our SIGCHLD, cover it, here:
- enqueue_reap();
- } else {
- my $ret = waitpid($pid, 0);
- if ($ret == $pid) {
- if ($cb) {
- eval { $cb->($arg, $pid) };
- carp "E: dwaitpid($pid) !in_loop: $@" if $@;
- }
- } else {
- carp "waitpid($pid, 0) = $ret, \$!=$!, \$?=$?";
- }
- }
-}
+sub dflush {} # overridden by DSdeflate
+sub compressed {} # overridden by DSdeflate
+sub long_response_done {} # overridden by Net::NNTP
-sub expire_old () {
- my $cur = $EXPMAP or return;
- $EXPMAP = undef;
- my $old = now() - $EXPTIME;
- while (my ($fd, $idle_at) = each %$cur) {
- if ($idle_at < $old) {
- my $ds_obj = $DescriptorMap{$fd};
- $EXPMAP->{$fd} = $idle_at if !$ds_obj->shutdn;
- } else {
- $EXPMAP->{$fd} = $idle_at;
- }
+sub long_step {
+ my ($self) = @_;
+ # wbuf is unset or empty, here; {long} may add to it
+ my ($fd, $cb, $t0, @args) = @{$self->{long_cb}};
+ my $more = eval { $cb->($self, @args) };
+ if ($@ || !$self->{sock}) { # something bad happened...
+ delete $self->{long_cb};
+ my $elapsed = now() - $t0;
+ $@ and warn("$@ during long response[$fd] - ",
+ sprintf('%0.6f', $elapsed),"\n");
+ $self->out(" deferred[$fd] aborted - %0.6f", $elapsed);
+ $self->close;
+ } elsif ($more) { # $self->{wbuf}:
+ # control passed to ibx_async_cat if $more == \undef
+ requeue_once($self) if !ref($more);
+ } else { # all done!
+ delete $self->{long_cb};
+ $self->long_response_done;
+ my $elapsed = now() - $t0;
+ my $fd = fileno($self->{sock});
+ $self->out(" deferred[$fd] done - %0.6f", $elapsed);
+ my $wbuf = $self->{wbuf}; # do NOT autovivify
+ requeue($self) unless $wbuf && @$wbuf;
}
- add_uniq_timer('expire', 60, \&expire_old) if $EXPMAP;
}
-sub update_idle_time {
+sub requeue_once {
my ($self) = @_;
- my $sock = $self->{sock} or return;
- $EXPMAP->{fileno($sock)} = now();
- add_uniq_timer('expire', 60, \&expire_old);
+ # COMPRESS users all share the same DEFLATE context.
+ # Flush it here to ensure clients don't see each other's data
+ $self->dflush;
+
+ # no recursion, schedule another call ASAP,
+ # but only after all pending writes are done.
+ # autovivify wbuf. wbuf may be populated by $cb,
+ # no need to rearm if so: (push returns new size of array)
+ $self->requeue if push(@{$self->{wbuf}}, \&long_step) == 1;
}
-sub not_idle_long {
- my ($self, $now) = @_;
+sub long_response ($$;@) {
+ my ($self, $cb, @args) = @_; # cb returns true if more, false if done
my $sock = $self->{sock} or return;
- my $idle_at = $EXPMAP->{fileno($sock)} or return;
- ($idle_at + $EXPTIME) > $now;
+ # make sure we disable reading during a long response,
+ # clients should not be sending us stuff and making us do more
+ # work while we are stream a response to them
+ $self->{long_cb} = [ fileno($sock), $cb, now(), @args ];
+ long_step($self); # kick off!
+ undef;
+}
+
+sub awaitpid {
+ my ($pid, @cb_args) = @_; # @cb_args = ($cb, @args), $cb may be undef
+ $AWAIT_PIDS->{$pid} = \@cb_args if @cb_args;
+ # provide synchronous API
+ if (defined(wantarray) || (!$in_loop && !@cb_args)) {
+ my $ret;
+again:
+ $ret = waitpid($pid, 0) // -2;
+ if ($ret == $pid) {
+ my $cb_args = delete $AWAIT_PIDS->{$pid};
+ @cb_args = @$cb_args if !@cb_args && $cb_args;
+ await_cb($pid, @cb_args);
+ } else {
+ goto again if $! == EINTR;
+ carp "waitpid($pid): $!";
+ delete $AWAIT_PIDS->{$pid};
+ }
+ return $ret;
+ } elsif ($in_loop) { # We could've just missed our SIGCHLD, cover it, here:
+ enqueue_reap();
+ }
}
1;