1 files changed, 35 insertions, 0 deletions
diff --git a/lib/plum/rack/thread_pool.rb b/lib/plum/rack/thread_pool.rb
new file mode 100644
index 0000000..9e07943
--- /dev/null
+++ b/lib/plum/rack/thread_pool.rb
@@ -0,0 +1,35 @@
+# -*- frozen-string-literal: true -*-
+module Plum
+  module Rack
+    class ThreadPool
+      def initialize(size = 20)
+        @workers = Set.new
+        @jobs = Queue.new
+
+        size.times { |i|
+          spawn_worker
+        }
+      end
+
+      # returns cancel token
+      def acquire(tag = nil, err = nil, &blk)
+        @jobs << [blk, err]
+      end
+
+      private
+      def spawn_worker
+        t = Thread.new {
+          while true
+            job, err = @jobs.pop
+            begin
+              job.call
+            rescue => e
+              err << e if err
+            end
+          end
+        }
+        @workers << t
+      end
+    end
+  end
+end