new accessors

db4
Doug Coleman 2008-08-30 21:19:06 -05:00
parent a97619b747
commit 98c2548fa3
2 changed files with 23 additions and 24 deletions

View File

@ -174,7 +174,7 @@ threads sequences calendar accessors ;
] ;
[ lock-timeout-test ] [
linked-error-thread name>> "Lock timeout-er" =
thread>> name>> "Lock timeout-er" =
] must-fail-with
:: read/write-test ( -- )

View File

@ -1,7 +1,7 @@
! Copyright (C) 2008 Slava Pestov.
! See http://factorcode.org/license.txt for BSD license.
USING: deques dlists kernel threads continuations math
concurrency.conditions ;
concurrency.conditions combinators.short-circuit accessors ;
IN: concurrency.locks
! Simple critical sections
@ -16,13 +16,13 @@ TUPLE: lock threads owner reentrant? ;
<PRIVATE
: acquire-lock ( lock timeout -- )
over lock-owner
[ 2dup >r lock-threads r> "lock" wait ] when drop
self swap set-lock-owner ;
over owner>>
[ 2dup >r threads>> r> "lock" wait ] when drop
self >>owner drop ;
: release-lock ( lock -- )
f over set-lock-owner
lock-threads notify-1 ;
f >>owner
threads>> notify-1 ;
: do-lock ( lock timeout quot acquire release -- )
>r >r pick rot r> call ! use up timeout acquire
@ -34,8 +34,8 @@ TUPLE: lock threads owner reentrant? ;
PRIVATE>
: with-lock-timeout ( lock timeout quot -- )
pick lock-reentrant? [
pick lock-owner self eq? [
pick reentrant?>> [
pick owner>> self eq? [
2nip call
] [
(with-lock)
@ -56,44 +56,43 @@ TUPLE: rw-lock readers writers reader# writer ;
<PRIVATE
: add-reader ( lock -- )
dup rw-lock-reader# 1+ swap set-rw-lock-reader# ;
[ 1+ ] change-reader# drop ;
: acquire-read-lock ( lock timeout -- )
over rw-lock-writer
[ 2dup >r rw-lock-readers r> "read lock" wait ] when drop
over writer>>
[ 2dup >r readers>> r> "read lock" wait ] when drop
add-reader ;
: notify-writer ( lock -- )
rw-lock-writers notify-1 ;
writers>> notify-1 ;
: remove-reader ( lock -- )
dup rw-lock-reader# 1- swap set-rw-lock-reader# ;
[ 1- ] change-reader# drop ;
: release-read-lock ( lock -- )
dup remove-reader
dup rw-lock-reader# zero? [ notify-writer ] [ drop ] if ;
dup reader#>> zero? [ notify-writer ] [ drop ] if ;
: acquire-write-lock ( lock timeout -- )
over rw-lock-writer pick rw-lock-reader# 0 > or
[ 2dup >r rw-lock-writers r> "write lock" wait ] when drop
self swap set-rw-lock-writer ;
over writer>> pick reader#>> 0 > or
[ 2dup >r writers>> r> "write lock" wait ] when drop
self >>writer drop ;
: release-write-lock ( lock -- )
f over set-rw-lock-writer
dup rw-lock-readers deque-empty?
[ notify-writer ] [ rw-lock-readers notify-all ] if ;
f >>writer
dup readers>> deque-empty?
[ notify-writer ] [ readers>> notify-all ] if ;
: reentrant-read-lock-ok? ( lock -- ? )
#! If we already have a write lock, then we can grab a read
#! lock too.
rw-lock-writer self eq? ;
writer>> self eq? ;
: reentrant-write-lock-ok? ( lock -- ? )
#! The only case where we have a writer and > 1 reader is
#! write -> read re-entrancy, and in this case we prohibit
#! a further write -> read -> write re-entrancy.
dup rw-lock-writer self eq?
swap rw-lock-reader# zero? and ;
{ [ writer>> self eq? ] [ reader#>> zero? ] } 1&& ;
PRIVATE>