X-Git-Url: http://git.kpe.io/?p=kmrcl.git;a=blobdiff_plain;f=macros.lisp;h=46894ba5e6fc82e3fc728c8cf2ea5688617e8e85;hp=5b7286590fa0e18647629f14171e3ffdb3c99a5c;hb=2f65fd6d93691f3943182138efd2013c3fdb67c7;hpb=e1c2b781af8e10e078ab95920ce0208eb9f5e6bf

diff --git a/macros.lisp b/macros.lisp
index 5b72865..46894ba 100644
--- a/macros.lisp
+++ b/macros.lisp
@@ -215,3 +215,21 @@
 				    ,element-type) ,table-name)
 		 (cons buffer buffers))))))))
 
+(defmacro def-cached-instance (name)
+  (let* ((new-name (concat-symbol "new-" name "-instance"))
+	 (release-name (concat-symbol "release-" name "-instance"))
+	 (cache-name (concat-symbol "*cached-" name "-instance-table*"))
+	 (lock-name (concat-symbol "*cached-" name "-instance-lock*")))
+    `(eval-when (:compile-toplevel :load-toplevel :execute)
+       (defvar ,cache-name nil)
+       (defvar ,lock-name (kmrcl::make-lock ',name))
+	 
+	 (defun ,new-name ()
+	   (kmrcl::with-lock-held (,lock-name)
+	     (if ,cache-name
+		 (pop ,cache-name)
+		 (make-instance ',name))))
+	 
+	 (defun ,release-name (instance)
+	   (kmrcl::with-lock-held (,lock-name)
+	     (push instance ,cache-name))))))