(in-package "SB!THREAD")
-(sb!xc:defmacro with-mutex ((mutex &key value (wait-p t)) &body body)
+(sb!xc:defmacro with-mutex ((mutex &key (value '*current-thread*) (wait-p t))
+ &body body)
#!+sb-doc
"Acquire MUTEX for the dynamic scope of BODY, setting it to
NEW-VALUE or some suitable default value if NIL. If WAIT-P is non-NIL
and the mutex is in use, sleep until it is available"
#!-sb-thread (declare (ignore mutex value wait-p))
#!+sb-thread
- (with-unique-names (got)
- `(let ((,got (get-mutex ,mutex ,value ,wait-p)))
- (when ,got
- (unwind-protect
- (locally ,@body)
- (release-mutex ,mutex)))))
+ (with-unique-names (got mutex1)
+ `(let ((,mutex1 ,mutex)
+ ,got)
+ (unwind-protect
+ ;; FIXME: async unwind in SETQ form
+ (when (setq ,got (get-mutex ,mutex1 ,value ,wait-p))
+ (locally
+ ,@body))
+ (when ,got
+ (release-mutex ,mutex1)))))
;; KLUDGE: this separate expansion for (NOT SB-THREAD) is not
;; strictly necessary; GET-MUTEX and RELEASE-MUTEX are implemented.
;; However, there would be a (possibly slight) performance hit in
(sb!xc:defmacro with-recursive-lock ((mutex) &body body)
#!+sb-doc
"Acquires MUTEX for the dynamic scope of BODY. Within that scope
-further recursive lock attempts for the same mutex succeed. However,
-it is an error to mix WITH-MUTEX and WITH-RECURSIVE-LOCK for the same
-mutex."
- #!-sb-thread (declare (ignore mutex))
- #!+sb-thread
- (with-unique-names (cfp inner-lock)
- `(let ((,cfp (sb!kernel:current-fp))
- (,inner-lock
- (and (mutex-value ,mutex)
- (sb!vm:control-stack-pointer-valid-p
- (sb!sys:int-sap
- (sb!kernel:get-lisp-obj-address (mutex-value ,mutex)))))))
- (unless ,inner-lock
- ;; this punning with MAKE-LISP-OBJ depends for its safety on
- ;; the frame pointer being a lispobj-aligned integer. While
- ;; it is, then MAKE-LISP-OBJ will always return a FIXNUM, so
- ;; we're safe to do that. Should this ever change, this
- ;; MAKE-LISP-OBJ could return something that looks like a
- ;; pointer, but pointing into neverneverland, which will
- ;; confuse GC completely. -- CSR, 2003-06-03
- (get-mutex ,mutex (sb!kernel:make-lisp-obj (sb!sys:sap-int ,cfp))))
- (unwind-protect
- (locally ,@body)
- (unless ,inner-lock
- (release-mutex ,mutex)))))
+further recursive lock attempts for the same mutex succeed. It is
+allowed to mix WITH-MUTEX and WITH-RECURSIVE-LOCK for the same mutex
+provided the default value is used for the mutex."
+ #!-sb-thread
+ (declare (ignore mutex)) #!+sb-thread
+ (with-unique-names (mutex1 inner-lock-p)
+ `(let* ((,mutex1 ,mutex)
+ (,inner-lock-p (eq (mutex-value ,mutex1) *current-thread*)))
+ (unwind-protect
+ (progn
+ (unless ,inner-lock-p
+ (get-mutex ,mutex1))
+ (locally
+ ,@body))
+ (unless ,inner-lock-p
+ (release-mutex ,mutex1)))))
#!-sb-thread
`(locally ,@body))