func loop(rc reflect.Value, wc reflect.Value) {
readCase := reflect.SelectCase{}
readCase.Dir = reflect.SelectRecv
readCase.Chan = wc
writeCase := reflect.SelectCase{}
writeCase.Dir = reflect.SelectSend
writeCase.Chan = rc
cases := []reflect.SelectCase{readCase, writeCase}
l := list.New()
for {
tc := cases[:1]
if l.Len() > 0 {
writeCase.Send = reflect.ValueOf(l.Front().Value)
cases[1] = writeCase
tc = cases[:2]
}
idx, v, ok := reflect.Select(tc)
if idx == 0 {
if ok {
l.PushBack(v.Interface())
} else {
//channel closed
log.Println("Read channel closed")
break
}
} else if idx == 1 {
l.Remove(l.Front())
}
}
}
func channelSelect(L *LState) int {
//TODO check case table size
cases := make([]reflect.SelectCase, L.GetTop())
top := L.GetTop()
for i := 0; i < top; i++ {
cas := reflect.SelectCase{reflect.SelectSend, reflect.ValueOf(nil), reflect.ValueOf(nil)}
tbl := L.CheckTable(i + 1)
dir, ok1 := tbl.RawGetInt(1).(LString)
if !ok1 {
L.ArgError(i+1, "invalid select case")
}
switch string(dir) {
case "<-|":
ch, ok := tbl.RawGetInt(2).(LChannel)
if !ok {
L.ArgError(i+1, "invalid select case")
}
cas.Chan = reflect.ValueOf((chan LValue)(ch))
v := tbl.RawGetInt(3)
if !isGoroutineSafe(v) {
L.ArgError(i+1, "can not send a function, userdata, thread or table that has a metatable")
}
cas.Send = reflect.ValueOf(v)
case "|<-":
ch, ok := tbl.RawGetInt(2).(LChannel)
if !ok {
L.ArgError(i+1, "invalid select case")
}
cas.Chan = reflect.ValueOf((chan LValue)(ch))
cas.Dir = reflect.SelectRecv
case "default":
cas.Dir = reflect.SelectDefault
default:
L.ArgError(i+1, "invalid channel direction:"+string(dir))
}
cases[i] = cas
}
pos, recv, rok := reflect.Select(cases)
lv := LNil
if recv.Kind() != 0 {
lv, _ = recv.Interface().(LValue)
if lv == nil {
lv = LNil
}
}
tbl := L.Get(pos + 1).(*LTable)
last := tbl.RawGetInt(tbl.Len())
if last.Type() == LTFunction {
L.Push(last)
switch cases[pos].Dir {
case reflect.SelectRecv:
if rok {
L.Push(LTrue)
} else {
L.Push(LFalse)
}
L.Push(lv)
L.Call(2, 0)
case reflect.SelectSend:
L.Push(tbl.RawGetInt(3))
L.Call(1, 0)
case reflect.SelectDefault:
L.Call(0, 0)
}
}
L.Push(LNumber(pos + 1))
L.Push(lv)
if rok {
L.Push(LTrue)
} else {
L.Push(LFalse)
}
return 3
}
