(in-package "SB!THREAD")
+(eval-when (:compile-toplevel :load-toplevel :execute)
+ (sb!xc:proclaim '(sb!ext:always-bound *current-thread*)))
+
(def!type thread-name ()
'simple-string)
in future versions."
(name nil :type (or thread-name null))
(%alive-p nil :type boolean)
+ (%ephemeral-p nil :type boolean)
(os-thread nil :type (or integer null))
(interruptions nil :type list)
(result nil :type list)
:type mutex)
waiting-for)
+(def!struct (foreign-thread
+ (:include thread)
+ (:conc-name "THREAD-"))
+ #!+sb-doc
+ "Type of native threads which are attached to the runtime as Lisp threads
+temporarily.")
+
+#!+(and sb-safepoint-strictly (not win32))
+(def!struct (signal-handling-thread
+ (:include foreign-thread)
+ (:conc-name "THREAD-"))
+ #!+sb-doc
+ "Asynchronous signal handling thread."
+ (signal-number nil :type integer))
+
(def!struct mutex
#!+sb-doc
"Mutex type."
(barrier (:write)))))
(exec)))))))
-(sb!xc:defmacro with-mutex ((mutex &key (value '*current-thread*) (wait-p t))
+(sb!xc:defmacro with-mutex ((mutex &key (wait-p t) timeout value)
&body body)
#!+sb-doc
- "Acquire MUTEX for the dynamic scope of BODY, setting it to 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"
+ "Acquire MUTEX for the dynamic scope of BODY. If WAIT-P is true (the default),
+and the MUTEX is not immediately available, sleep until it is available.
+
+If TIMEOUT is given, it specifies a relative timeout, in seconds, on how long
+the system should try to acquire the lock in the contested case.
+
+If the mutex isn't acquired succesfully due to either WAIT-P or TIMEOUT, the
+body is not executed, and WITH-MUTEX returns NIL.
+
+Otherwise body is executed with the mutex held by current thread, and
+WITH-MUTEX returns the values of BODY.
+
+Historically WITH-MUTEX also accepted a VALUE argument, which when provided
+was used as the new owner of the mutex instead of the current thread. This is
+no longer supported: if VALUE is provided, it must be either NIL or the
+current thread."
`(dx-flet ((with-mutex-thunk () ,@body))
(call-with-mutex
#'with-mutex-thunk
,mutex
,value
- ,wait-p)))
+ ,wait-p
+ ,timeout)))
(sb!xc:defmacro with-system-mutex ((mutex
&key without-gcing allow-with-interrupts)
#'with-system-mutex-thunk
,mutex)))
-(sb!xc:defmacro with-recursive-lock ((mutex) &body body)
+(sb!xc:defmacro with-recursive-lock ((mutex &key (wait-p t) timeout) &body body)
#!+sb-doc
- "Acquires MUTEX for the dynamic scope of BODY. Within that scope
-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."
+ "Acquire MUTEX for the dynamic scope of BODY.
+
+If WAIT-P is true (the default), and the MUTEX is not immediately available or
+held by the current thread, sleep until it is available.
+
+If TIMEOUT is given, it specifies a relative timeout, in seconds, on how long
+the system should try to acquire the lock in the contested case.
+
+If the mutex isn't acquired succesfully due to either WAIT-P or TIMEOUT, the
+body is not executed, and WITH-RECURSIVE-LOCK returns NIL.
+
+Otherwise body is executed with the mutex held by current thread, and
+WITH-RECURSIVE-LOCK returns the values of BODY.
+
+Unlike WITH-MUTEX, which signals an error on attempt to re-acquire an already
+held mutex, WITH-RECURSIVE-LOCK allows recursive lock attempts to succeed."
`(dx-flet ((with-recursive-lock-thunk () ,@body))
(call-with-recursive-lock
#'with-recursive-lock-thunk
- ,mutex)))
+ ,mutex
+ ,wait-p
+ ,timeout)))
(sb!xc:defmacro with-recursive-system-lock ((lock
&key without-gcing)
(flet ((%call-with-system-mutex ()
(dx-let (got-it)
(unwind-protect
- (when (setf got-it (get-mutex mutex))
+ (when (setf got-it (grab-mutex mutex))
(funcall function))
(when got-it
(release-mutex mutex))))))
#!-sb-thread
(progn
- (defun call-with-mutex (function mutex value waitp)
- (declare (ignore mutex value waitp)
+ (defun call-with-mutex (function mutex value waitp timeout)
+ (declare (ignore mutex waitp timeout)
(function function))
+ (unless (or (null value) (eq *current-thread* value))
+ (error "~S called with non-nil :VALUE that isn't the current thread."
+ 'with-mutex))
(funcall function))
- (defun call-with-recursive-lock (function mutex)
- (declare (ignore mutex) (function function))
+ (defun call-with-recursive-lock (function mutex waitp timeout)
+ (declare (ignore mutex waitp timeout)
+ (function function))
(funcall function))
(defun call-with-recursive-system-lock (function lock)
;;; closes over GOT-IT causes a value-cell to be allocated for it --
;;; and we prefer that to go on the stack since it can.
(progn
- (defun call-with-mutex (function mutex value waitp)
+ (defun call-with-mutex (function mutex value waitp timeout)
(declare (function function))
+ (unless (or (null value) (eq *current-thread* value))
+ (error "~S called with non-nil :VALUE that isn't the current thread."
+ 'with-mutex))
(dx-let ((got-it nil))
(without-interrupts
(unwind-protect
(when (setq got-it (allow-with-interrupts
- (get-mutex mutex value waitp)))
+ (grab-mutex mutex :waitp waitp
+ :timeout timeout)))
(with-local-interrupts (funcall function)))
(when got-it
(release-mutex mutex))))))
- (defun call-with-recursive-lock (function mutex)
+ (defun call-with-recursive-lock (function mutex waitp timeout)
(declare (function function))
(dx-let ((inner-lock-p (eq (mutex-%owner mutex) *current-thread*))
(got-it nil))
(without-interrupts
(unwind-protect
(when (or inner-lock-p (setf got-it (allow-with-interrupts
- (get-mutex mutex))))
+ (grab-mutex mutex :waitp waitp
+ :timeout timeout))))
(with-local-interrupts (funcall function)))
(when got-it
(release-mutex mutex))))))