-(in-package :sb!thread)
+;;;; support for threads needed at cross-compile time
-(sb!xc:defmacro with-recursive-lock ((mutex) &body body)
+;;;; This software is part of the SBCL system. See the README file for
+;;;; more information.
+;;;;
+;;;; This software is derived from the CMU CL system, which was
+;;;; written at Carnegie Mellon University and released into the
+;;;; public domain. The software is in the public domain and is
+;;;; provided with absolutely no warranty. See the COPYING and CREDITS
+;;;; files for more information.
+
+(in-package "SB!THREAD")
+
+(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
- (let ((cfp (gensym "CFP")))
- `(let ((,cfp (ash (sb!sys:sap-int (sb!vm::current-fp) ) -2)))
- (unless (and (mutex-value ,mutex)
- (SB!DI::control-stack-pointer-valid-p
- (sb!sys:int-sap (ash (mutex-value ,mutex) 2))))
- (get-mutex ,mutex ,cfp))
- (unwind-protect
- (progn ,@body)
- (when (eql (mutex-value ,mutex) ,cfp) (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
+ ;; using them.
#!-sb-thread
- `(progn ,@body))
-
-#!+sb-thread
-(defun get-foreground ()
- (when (not (eql (mutex-value *session-lock*) (current-thread-id)))
- (get-mutex *session-lock*))
- (sb!sys:enable-interrupt :sigint #'sb!unix::sigint-handler)
- t)
-#!-sb-thread
-(defun get-foreground () t)
+ `(locally ,@body))
-#!+sb-thread
-(defun release-foreground ()
- (sb!sys:enable-interrupt :sigint :ignore)
- (release-mutex *session-lock*)
- t)
-#!-sb-thread
-(defun release-foreground () t)
+(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. 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))