1 files changed, 39 insertions, 0 deletions
diff --git a/util/queue.lua b/util/queue.lua
new file mode 100644
index 0000000..8c9c373
--- /dev/null
+++ b/util/queue.lua
@@ -0,0 +1,39 @@
+local cqueues = require'cqueues'
+local condition = require'cqueues.condition'
+local cqaux = require'cqueues.auxlib'
+
+local Queue = {}
+
+function Queue.make()
+	return setmetatable({
+		items = {},
+		cv = condition.new(),
+	}, {__index=Queue})
+end
+
+function Queue.enqueue(self, ...)
+	local item = table.pack(...)
+	table.insert(self.items, item)
+	if #self.items > 128 then
+		print('warning: queue is quite big')
+	end
+	self.cv:signal()
+end
+
+function Queue.iter(self)
+	return cqaux.wrap(function()
+		while true do
+			while #self.items > 0 do
+				local items = self.items
+				self.items = {} -- the old switcheroo
+				for _, item in ipairs(items) do
+					coroutine.yield(table.unpack(item, 1, item.n))
+				end
+			end
+			self.cv:wait()
+		end
+	end)
+end
+
+
+return Queue