ipc: wq: handle >MAX_ARG_STRLEN && <EMSGSIZE case

[public-inbox.git] / lib / PublicInbox / IPC.pm

diff --git a/lib/PublicInbox/IPC.pm b/lib/PublicInbox/IPC.pm
index 24237773903373ca63f3b0783da537b678a841b8..497a6035aa747704f189f2c740d91cd26174c5fa 100644 (file)
--- a/lib/PublicInbox/IPC.pm
+++ b/lib/PublicInbox/IPC.pm
@@ -17,6 +17,7 @@ use PublicInbox::Spawn;
 use PublicInbox::OnDestroy;
 use PublicInbox::WQWorker;
 use Socket qw(AF_UNIX MSG_EOR SOCK_STREAM);
+my $MY_MAX_ARG_STRLEN = 4096 * 33; # extra 4K for serialization
 my $SEQPACKET = eval { Socket::SOCK_SEQPACKET() }; # portable enough?
 our @EXPORT_OK = qw(ipc_freeze ipc_thaw);
 my $WQ_MAX_WORKERS = 4096;
@@ -213,7 +214,7 @@ sub ipc_sibling_atfork_child {
 
 sub recv_and_run {
        my ($self, $s2, $len, $full_stream) = @_;
-       my @fds = $recv_cmd->($s2, my $buf, $len);
+       my @fds = $recv_cmd->($s2, my $buf, $len // $MY_MAX_ARG_STRLEN);
        return if scalar(@fds) && !defined($fds[0]);
        my $n = length($buf) or return 0;
        my $nfd = 0;
@@ -268,27 +269,37 @@ sub wq_broadcast {
        }
 }
 
+sub stream_in_full ($$$) {
+       my ($s1, $fds, $buf) = @_;
+       socketpair(my $r, my $w, AF_UNIX, SOCK_STREAM, 0) or
+               croak "socketpair: $!";
+       my $n = $send_cmd->($s1, [ fileno($r) ],
+                       ipc_freeze(['do_sock_stream', length($buf)]),
+                       MSG_EOR) // croak "sendmsg: $!";
+       undef $r;
+       $n = $send_cmd->($w, $fds, $buf, 0) // croak "sendmsg: $!";
+       while ($n < length($buf)) {
+               my $x = syswrite($w, $buf, length($buf) - $n, $n) //
+                               croak "syswrite: $!";
+               croak "syswrite wrote 0 bytes" if $x == 0;
+               $n += $x;
+       }
+}
+
 sub wq_io_do { # always async
        my ($self, $sub, $ios, @args) = @_;
        if (my $s1 = $self->{-wq_s1}) { # run in worker
                my $fds = [ map { fileno($_) } @$ios ];
                my $buf = ipc_freeze([$sub, @args]);
-               my $n = $send_cmd->($s1, $fds, $buf, MSG_EOR);
-               return if defined($n); # likely
-               croak "sendmsg: $! (check RLIMIT_NOFILE)" if $!{ETOOMANYREFS};
-               croak "sendmsg: $!" if !$!{EMSGSIZE};
-               socketpair(my $r, my $w, AF_UNIX, SOCK_STREAM, 0) or
-                       croak "socketpair: $!";
-               $n = $send_cmd->($s1, [ fileno($r) ],
-                               ipc_freeze(['do_sock_stream', length($buf)]),
-                               MSG_EOR) // croak "sendmsg: $!";
-               undef $r;
-               $n = $send_cmd->($w, $fds, $buf, 0) // croak "sendmsg: $!";
-               while ($n < length($buf)) {
-                       my $x = syswrite($w, $buf, length($buf) - $n, $n) //
-                                       croak "syswrite: $!";
-                       croak "syswrite wrote 0 bytes" if $x == 0;
-                       $n += $x;
+               if (length($buf) > $MY_MAX_ARG_STRLEN) {
+                       stream_in_full($s1, $fds, $buf);
+               } else {
+                       my $n = $send_cmd->($s1, $fds, $buf, MSG_EOR);
+                       return if defined($n); # likely
+                       $!{ETOOMANYREFS} and
+                               croak "sendmsg: $! (check RLIMIT_NOFILE)";
+                       $!{EMSGSIZE} ? stream_in_full($s1, $fds, $buf) :
+                       croak("sendmsg: $!");
                }
        } else {
                @$self{0..$#$ios} = @$ios;