X-Git-Url: http://www.git.stargrave.org/?a=blobdiff_plain;f=lib%2FPublicInbox%2FDS.pm;h=0a763d0ef643ad0d5c5deb8e027b9df67d4438ae;hb=HEAD;hp=f0181b5461cfc4111574af2991d3522a57aba174;hpb=a5e39d0e4e2d9b7ad937e8dd9af726d96eec6126;p=public-inbox.git

diff --git a/lib/PublicInbox/DS.pm b/lib/PublicInbox/DS.pm
index f0181b54..0a763d0e 100644
--- a/lib/PublicInbox/DS.pm
+++ b/lib/PublicInbox/DS.pm
@@ -30,13 +30,13 @@ use Time::HiRes qw(clock_gettime CLOCK_MONOTONIC);
 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 $AWAIT_PIDS; # pid => [ $callback, @args ]
 my $reap_armed;
 my $ToClose; # sockets to close when event loop is done
 our (
@@ -74,10 +74,10 @@ sub Reset {
 		# we may be iterating inside one of these on our stack
 		my @q = delete @Stack{keys %Stack};
 		for my $q (@q) { @$q = () }
-		$wait_pids = $nextq = $ToClose = undef;
+		$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));
 
@@ -126,12 +126,11 @@ sub add_uniq_timer { # ($name, $secs, $coderef, @args) = @_;
 
 # caller sets return value to $Epoll
 sub _InitPoller () {
-	if (PublicInbox::Syscall::epoll_defined())  {
+	if (defined $PublicInbox::Syscall::SYS_epoll_create)  {
 		my $fd = epoll_create();
 		die "epoll_create: $!" if $fd < 0;
 		open($ep_io, '+<&=', $fd) or return;
-		my $fl = fcntl($ep_io, F_GETFD, 0);
-		fcntl($ep_io, F_SETFD, $fl | FD_CLOEXEC);
+		fcntl($ep_io, F_SETFD, FD_CLOEXEC);
 		$fd;
 	} else {
 		my $cls;
@@ -202,33 +201,30 @@ sub block_signals () {
 	$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)
@@ -648,38 +644,80 @@ sub shutdn ($) {
     }
 }
 
-sub zflush {} # overridden by NNTPdeflate and IMAPdeflate
+sub dflush {} # overridden by DSdeflate
+sub compressed {} # overridden by DSdeflate
+sub long_response_done {} # overridden by Net::NNTP
+
+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;
+	}
+}
 
 sub requeue_once {
 	my ($self) = @_;
 	# COMPRESS users all share the same DEFLATE context.
-	# Flush it here to ensure clients don't see
-	# each other's data
-	$self->zflush;
+	# 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 $cb,
 	# no need to rearm if so: (push returns new size of array)
-	requeue($self) if push(@{$self->{wbuf}}, $self->can('long_step')) == 1;
+	$self->requeue if push(@{$self->{wbuf}}, \&long_step) == 1;
 }
 
-sub dwaitpid ($;$$) {
-	my ($pid, $cb, $arg) = @_;
-	if ($in_loop) {
-		push @$wait_pids, [ $pid, $cb, $arg ];
-		# We could've just missed our SIGCHLD, cover it, here:
-		enqueue_reap();
-	} else {
-		my $ret = waitpid($pid, 0);
+sub long_response ($$;@) {
+	my ($self, $cb, @args) = @_; # cb returns true if more, false if done
+	my $sock = $self->{sock} or return;
+	# 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 == $pid) {
-			if ($cb) {
-				eval { $cb->($arg, $pid) };
-				carp "E: dwaitpid($pid) !in_loop: $@" if $@;
-			}
+			my $cb_args = delete $AWAIT_PIDS->{$pid};
+			@cb_args = @$cb_args if !@cb_args && $cb_args;
+			await_cb($pid, @cb_args);
 		} else {
-			carp "waitpid($pid, 0) = $ret, \$!=$!, \$?=$?";
+			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();
 	}
 }