From: Scott Worley Date: Sun, 19 Aug 2012 16:51:53 +0000 (-0700) Subject: Monotonic clock X-Git-Url: http://git.scottworley.com/reliable-chat/commitdiff_plain/2ee4581bb573fb3a3df74f9359a59d51ac41c483?ds=inline;hp=9878d03bc1ec4a37d501ee65b520630235cc86cf Monotonic clock --- diff --git a/server/server.go b/server/server.go index 8dce69b..c3bb593 100644 --- a/server/server.go +++ b/server/server.go @@ -53,7 +53,39 @@ type Store struct { Get chan *StoreRequest } -// TODO: Monotonic clock +var monotonic_clock chan chan time.Time + +const minimum_clock_increment = time.Millisecond + +func start_clock() { + internal_monotonic_clock := make(chan chan time.Time, 1) + go func() { + last_time := time.Now() + main: + for { + select { + case request, ok := <-internal_monotonic_clock: + if !ok { + break main + } + earliest_acceptable_time := last_time.Add(minimum_clock_increment) + current_time := time.Now() + if current_time.Before(earliest_acceptable_time) { + current_time = earliest_acceptable_time + } + request <- current_time + last_time = current_time + } + } + }() + monotonic_clock = internal_monotonic_clock +} + +func now() time.Time { + c := make(chan time.Time, 0) + monotonic_clock <- c + return <-c +} func manage_store(store Store) { messages := list.New() @@ -149,7 +181,7 @@ func start_server(store Store) { http.HandleFunc("/speak", func(w http.ResponseWriter, r *http.Request) { store.Add <- &Message{ - time.Now(), + now(), r.FormValue("id"), r.FormValue("text")} }) @@ -163,7 +195,8 @@ func start_server(store Store) { func main() { flag.Parse() - start_time.Set(time.Now().UnixNano()) + start_clock() + start_time.Set(now().UnixNano()) store := start_store() start_server(store) }