1 files changed, 28 insertions, 10 deletions
diff --git a/lib/PublicInbox/Qspawn.pm b/lib/PublicInbox/Qspawn.pm
index 9299096a..cc9c340d 100644
--- a/lib/PublicInbox/Qspawn.pm
+++ b/lib/PublicInbox/Qspawn.pm
@@ -1,12 +1,14 @@
  # Copyright (C) 2016 all contributors <meta@public-inbox.org>
  # License: AGPL-3.0+ <https://www.gnu.org/licenses/agpl-3.0.txt>
+
+# Limits the number of processes spawned
+# This does not depend on Danga::Socket or any other external
+# scheduling mechanism, you just need to call start and finish
+# appropriately
  package PublicInbox::Qspawn;
  use strict;
  use warnings;
  use PublicInbox::Spawn qw(popen_rd);
-our $LIMIT = 1;
-my $running = 0;
-my @run_queue;
  
  sub new ($$$;) {
          my ($class, $cmd, $env, $opt) = @_;
@@ -16,9 +18,10 @@ sub new ($$$;) {
  sub _do_spawn {
          my ($self, $cb) = @_;
          my $err;
+
          ($self->{rpipe}, $self->{pid}) = popen_rd(@{$self->{args}});
          if (defined $self->{pid}) {
-                $running++;
+                $self->{limiter}->{running}++;
          } else {
                  $self->{err} = $!;
          }
@@ -27,26 +30,41 @@ sub _do_spawn {
  
  sub finish ($) {
          my ($self) = @_;
+        my $limiter = $self->{limiter};
          if (delete $self->{rpipe}) {
                  my $pid = delete $self->{pid};
                  $self->{err} = $pid == waitpid($pid, 0) ? $? :
                                  "PID:$pid still running?";
-                $running--;
+                $limiter->{running}--;
          }
-        if (my $next = shift @run_queue) {
+        if (my $next = shift @{$limiter->{run_queue}}) {
                  _do_spawn(@$next);
          }
          $self->{err};
  }
  
-sub start ($$) {
-        my ($self, $cb) = @_;
+sub start {
+        my ($self, $limiter, $cb) = @_;
+        $self->{limiter} = $limiter;
  
-        if ($running < $LIMIT) {
+        if ($limiter->{running} < $limiter->{limit}) {
                  _do_spawn($self, $cb);
          } else {
-                push @run_queue, [ $self, $cb ];
+                push @{$limiter->{run_queue}}, [ $self, $cb ];
          }
  }
  
+package PublicInbox::Qspawn::Limiter;
+use strict;
+use warnings;
+
+sub new {
+        my ($class, $limit) = @_;
+        bless {
+                limit => $limit || 1,
+                running => 0,
+                run_queue => [],
+        }, $class;
+}
+
  1;