X-Git-Url: http://www.git.stargrave.org/?p=public-inbox.git;a=blobdiff_plain;f=lib%2FPublicInbox%2FDS.pm;fp=lib%2FPublicInbox%2FDS.pm;h=9563a1cbbbb5795fc724c9b3d19b8e76dd66a7ab;hp=e4629e97acc461aaa2debbe1687db8f0aecab796;hb=6e9397d12635eae55c9114ed9689413154fed8ce;hpb=a1ee3e0d84fedc4a2dd4e16e7054ee6fdfbe111a

diff --git a/lib/PublicInbox/DS.pm b/lib/PublicInbox/DS.pm
index e4629e97..9563a1cb 100644
--- a/lib/PublicInbox/DS.pm
+++ b/lib/PublicInbox/DS.pm
@@ -32,11 +32,12 @@ use PublicInbox::Syscall qw(:epoll);
 use PublicInbox::Tmpfile;
 use Errno qw(EAGAIN EINVAL);
 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 dwaitpid 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 (
@@ -74,11 +75,11 @@ 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 = $wait_pids = $nextq = $ToClose = undef;
 		$ep_io = undef; # closes real $Epoll FD
 		$Epoll = undef; # may call DSKQXS::DESTROY
 	} while (@Timers || keys(%Stack) || $nextq || $wait_pids ||
-		$ToClose || keys(%DescriptorMap) ||
+		$ToClose || keys(%DescriptorMap) || $AWAIT_PIDS ||
 		$PostLoopCallback || keys(%UniqTimer));
 
 	$reap_armed = undef;
@@ -201,6 +202,13 @@ sub block_signals () {
 	$oldset;
 }
 
+sub await_cb ($;@) {
+	my ($pid, @cb_args) = @_;
+	my $cb = shift @cb_args or return;
+	eval { $cb->($pid, @cb_args) };
+	warn "E: awaitpid($pid): $@" if $@;
+}
+
 # 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()
@@ -208,10 +216,12 @@ sub block_signals () {
 
 sub reap_pids {
 	$reap_armed = undef;
-	my $tmp = $wait_pids or return;
+	my $tmp = $wait_pids // [];
 	$wait_pids = undef;
 	$Stack{reap_runq} = $tmp;
 	my $oldset = block_signals();
+
+	# old API
 	foreach my $ary (@$tmp) {
 		my ($pid, $cb, $arg) = @$ary;
 		my $ret = waitpid($pid, WNOHANG);
@@ -226,6 +236,14 @@ sub reap_pids {
 			warn "waitpid($pid, WNOHANG) = $ret, \$!=$!, \$?=$?";
 		}
 	}
+
+	# new API TODO: convert to waitpid(-1) in the future as long
+	# as we don't use threads
+	for my $pid (keys %$AWAIT_PIDS) {
+		my $wpid = waitpid($pid, WNOHANG) // next;
+		my $cb_args = delete $AWAIT_PIDS->{$wpid} or next;
+		await_cb($pid, @$cb_args);
+	}
 	sig_setmask($oldset);
 	delete $Stack{reap_runq};
 }
@@ -720,6 +738,23 @@ sub dwaitpid ($;$$) {
 	}
 }
 
+sub awaitpid {
+	my ($pid, @cb_args) = @_;
+	$AWAIT_PIDS->{$pid} //= @cb_args ? \@cb_args : 0;
+	# provide synchronous API
+	if (defined(wantarray) || (!$in_loop && !@cb_args)) {
+		my $ret = waitpid($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);
+			return $ret;
+		}
+	}
+	# We could've just missed our SIGCHLD, cover it, here:
+	enqueue_reap() if $in_loop;
+}
+
 1;
 
 =head1 AUTHORS (Danga::Socket)