ecl/contrib/package-locks/package-locks.lisp
2016-11-11 09:30:50 +01:00

58 lines
1.9 KiB
Common Lisp

;;;; -*- Mode: Lisp; Syntax: Common-Lisp; Package: C -*-
;;;;
;;;; Copyright (c) 2016 Daniel Kochmańskin
;;;;
;;;; See file 'LICENSE' for the copyright details.
;;;; PACKAGE-LOCKS Convenient interface for package-locks mechanism.
(in-package "EXT")
;;; Package locks
(pushnew :package-locks *features*)
(defun lock-package (package &aux (package (si:coerce-to-package package)))
(ffi:c-inline (package) (:object) :void
"(#0)->pack.locked = 1"
:side-effects t
:one-liner t)
T)
(defun unlock-package (package &aux (package (si:coerce-to-package package)))
(ffi:c-inline (package) (:object) :void
"(#0)->pack.locked = 0"
:side-effects t
:one-liner t)
T)
(defun package-locked-p (package &aux (package (si:coerce-to-package package)))
"Returns T when PACKAGE is locked, NIL otherwise. Signals an error
if PACKAGE doesn't designate a valid package."
(ffi:c-inline (package) (:object) :object
"(#0)->pack.locked ? ECL_T : ECL_NIL"
:side-effects nil
:one-liner t))
(defmacro without-package-locks (&body body)
"Ignores all runtime package lock violations during the execution of
body. Body can begin with declarations."
`(let ((si::*ignore-package-locks* t)) ,@body))
(defmacro with-unlocked-packages ((&rest packages) &body forms)
"Unlocks PACKAGES for the dynamic scope of the body. Signals an
error if any of PACKAGES is not a valid package designator."
(with-unique-names (unlocked-packages)
`(let (,unlocked-packages)
(unwind-protect
(progn
(dolist (p ',packages)
(when (package-locked-p p)
(push p ,unlocked-packages)
(unlock-package p)))
,@forms)
(dolist (p ,unlocked-packages)
(when (find-package p)
(lock-package p)))))))
(provide '#:package-locks)