threads.lua

-- Copyright (c) 2011 by Robert G. Jakabosky <bobby@sharedrealm.com>
--
-- Permission is hereby granted, free of charge, to any person obtaining a copy
-- of this software and associated documentation files (the "Software"), to deal
-- in the Software without restriction, including without limitation the rights
-- to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
-- copies of the Software, and to permit persons to whom the Software is
-- furnished to do so, subject to the following conditions:
--
-- The above copyright notice and this permission notice shall be included in
-- all copies or substantial portions of the Software.
--
-- THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
-- IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
-- FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
-- AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
-- LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
-- OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
-- THE SOFTWARE.

--
-- zmq.thread wraps the low-level threads object & a zmq context.
--

local zmq = require"zmq"
local llthreads = require"llthreads"

local bootstrap_pre = [[
local action, action_arg, parent_ctx = ...
local func
]]

local bootstrap_post = [[

-- copy parent ZeroMQ context to this child thread.
local zmq = require"zmq"
local zthreads = require"zmq.threads"
if parent_ctx then
	zthreads.set_parent_ctx(zmq.init_ctx(parent_ctx))
end

-- create global 'arg'
arg = { select(4, ...) }

-- load Lua code.
if action == 'runfile' then
	func = assert(loadfile(action_arg))
	-- script name
	arg[0] = action_arg
elseif action == 'runstring' then
	func = assert(loadstring(action_arg))
	-- fake script name
	arg[0] = '=(loadstring)'
end

-- run loaded code.
return func(select(4, ...))
]]

local bootstrap_code = bootstrap_pre..bootstrap_post

local function new_thread(ctx, action, action_arg, ...)
	-- convert ZMQ_Ctx to lightuserdata.
	if ctx then
		ctx = ctx:lightuserdata()
	end
	return llthreads.new(bootstrap_code, action, action_arg, ctx, ...)
end

local M = {}

function M.set_bootstrap_prelude(code)
   bootstrap_code = bootstrap_pre .. code .. bootstrap_post
end

function M.runfile(ctx, file, ...)
	return new_thread(ctx, 'runfile', file, ...)
end

function M.runstring(ctx, code, ...)
	return new_thread(ctx, 'runstring', code, ...)
end

local parent_ctx = nil
function M.set_parent_ctx(ctx)
	parent_ctx = ctx
end

function M.get_parent_ctx(ctx)
	return parent_ctx
end

zmq.threads = M
return M