emulator.lua v0.3

--[[
kazagistars emulator
Do whatever you want with it, no rights reserved, as per WTFPL
(http://sam.zoy.org/wtfpl/COPYING)

Sometimes you just want to run something as if you didn't have a reactor
churning away below doing cool things. So, you can use the emulator!
Just call emulator:run(program) with a file name or function to run, and it
will be run in parallel with everything else running in the reactor,
including other emulated programs.
--]]
if not emulator then
if not reactor then error 'emulator: missing dependancy "reactor"' end

emulator = {}
emulator.threads = {} -- List of threads
emulator.waiting = {} -- List of events they are waiting for
emulator.nextid = 1
emulator.count = 0
emulator.run = function(e, program)
    local func
    if type(program) == "string" then
        func = function() shell.run(program) end
    elseif type(program) == "function" then
        func = program
    else
        error("Emulator param must be a program")
    end
    local new = e.nextid
    e.nextid = new + 1
    e.count = e.count + 1
    e.threads[new] = coroutine.create(func)
    e.waiting[new] = "emulator.init"
    reactor:register(nil, "emulator", emulator)
    os.queueEvent("emulator.init")
end

emulator.mt = {__call = function(e, event, name, ...)
    local dead = {}
    for id, thread in pairs(e.threads) do
        if (not e.waiting[id]) or (e.waiting[id] == event) then
            success, filter = coroutine.resume(thread, event, ...)
            if not success then
                print("Emulated thread error: "..filter)
            end
            if coroutine.status(thread) == "dead" then
                dead[#dead+1] = id
            end
            e.waiting[id] = filter
        end
    end
    for _,id in ipairs(dead) do
        e.threads[id] = nil
        e.waiting[id] = nil
        e.count = e.count - 1
    end
    if e.count == 0 then reactor:unregister(nil, "emulator") end
end}
setmetatable(emulator, emulator.mt)

end