contrib/sb-bsd-sockets/malloc.lisp

   1 (in-package :sb-bsd-sockets-internal)
   2
   3 (defun malloc (size)
   4   "Allocate foreign memory in some way that allows the garbage collector to free it later.  Note that memory allocated this way does not count as `consed' for the purposes of deciding when to gc, so explicitly calling EXT:GC occasionally would be a good idea if you use it a lot"
   5   ;; we can attach finalizers to any object, and they'll be called on
   6   ;; the next gc after the object no longer has references.  We can't
   7   ;; however make the finalizer close over the object, or it'll never
   8   ;; have no references.  I experimentally determined that (sap-alien
   9   ;; (alien-sap f)) is not EQ to f, so we can do it that way
  10   (let* ((memory (make-alien (unsigned 8) size))
  11          (alias (sap-alien (alien-sap memory)
  12                                  (* (unsigned 8)))))
  13     (sb-ext:finalize memory
  14                      (lambda ()
  15                        (free-alien alias)))))
  16