-(defmacro with-mutex ((mutex &key value (wait-p t)) &body body)
- (cond ((not wait-p)
- `(unless (mutex-value ,mutex)
- (unwind-protect
- (progn
- (setf (mutex-value ,mutex) (or ,value t))
- ,@body)
- (setf (mutex-value ,mutex) nil))))
- (t
- `(progn ,@body))))
+(defun get-mutex (lock &optional new-value (wait-p t))
+ (declare (type mutex lock))
+ (let ((old-value (mutex-value lock)))
+ (when (and old-value wait-p)
+ (error "In unithread mode, mutex ~S was requested with WAIT-P ~S and ~
+ new-value ~S, but has already been acquired (with value ~S)."
+ lock wait-p new-value old-value))
+ (setf (mutex-value lock) new-value)
+ t))
+
+(defun release-mutex (lock)
+ (declare (type mutex lock))
+ (setf (mutex-value lock) nil))