factor/basis/alarms/alarms.factor

95 lines
2.3 KiB
Factor

! Copyright (C) 2005, 2008 Slava Pestov, Doug Coleman.
! See http://factorcode.org/license.txt for BSD license.
USING: accessors assocs boxes calendar
combinators.short-circuit fry heaps init kernel math.order
namespaces quotations threads math system ;
IN: alarms
TUPLE: alarm
{ quot callable initial: [ ] }
{ start integer }
interval
{ entry box } ;
<PRIVATE
SYMBOL: alarms
SYMBOL: alarm-thread
: notify-alarm-thread ( -- )
alarm-thread get-global interrupt ;
GENERIC: >nanoseconds ( obj -- duration/f )
M: f >nanoseconds ;
M: real >nanoseconds >integer ;
M: duration >nanoseconds duration>nanoseconds >integer ;
: <alarm> ( quot start interval -- alarm )
alarm new
swap >nanoseconds >>interval
swap >nanoseconds nano-count + >>start
swap >>quot
<box> >>entry ;
: register-alarm ( alarm -- )
[ dup start>> alarms get-global heap-push* ]
[ entry>> >box ] bi
notify-alarm-thread ;
: alarm-expired? ( alarm n -- ? )
[ start>> ] dip <= ;
: reschedule-alarm ( alarm -- )
dup interval>> nano-count + >>start register-alarm ;
: call-alarm ( alarm -- )
[ entry>> box> drop ]
[ dup interval>> [ reschedule-alarm ] [ drop ] if ]
[ quot>> "Alarm execution" spawn drop ] tri ;
: (trigger-alarms) ( alarms n -- )
over heap-empty? [
2drop
] [
over heap-peek drop over alarm-expired? [
over heap-pop drop call-alarm (trigger-alarms)
] [
2drop
] if
] if ;
: trigger-alarms ( alarms -- )
nano-count (trigger-alarms) ;
: next-alarm ( alarms -- nanos/f )
dup heap-empty? [ drop f ] [ heap-peek drop start>> ] if ;
: alarm-thread-loop ( -- )
alarms get-global
dup next-alarm sleep-until
trigger-alarms ;
: cancel-alarms ( alarms -- )
[
heap-pop-all [ nip entry>> box> drop ] assoc-each
] when* ;
: init-alarms ( -- )
alarms [ cancel-alarms <min-heap> ] change-global
[ alarm-thread-loop t ] "Alarms" spawn-server
alarm-thread set-global ;
[ init-alarms ] "alarms" add-startup-hook
PRIVATE>
: add-alarm ( quot start interval -- alarm )
<alarm> [ register-alarm ] keep ;
: later ( quot duration -- alarm ) f add-alarm ;
: every ( quot duration -- alarm ) dup add-alarm ;
: cancel-alarm ( alarm -- )
entry>> [ alarms get-global heap-delete ] if-box? ;