add wrappers of some system functions to manipulate POSIX.1e ACLs

Signed-off-by: Sean Whitton <spwhitton@spwhitton.name>

1 files changed, 59 insertions, 0 deletions

diff --git a/src/util/posix1e.lisp b/src/util/posix1e.lisp
new file mode 100644
index 0000000..05525ab
--- /dev/null
+++ b/src/util/posix1e.lisp
@@ -0,0 +1,59 @@
+;;; Consfigurator -- Lisp declarative configuration management system
+
+;;; Copyright (C) 2021  Sean Whitton <spwhitton@spwhitton.name>
+
+;;; This file is free software; you can redistribute it and/or modify
+;;; it under the terms of the GNU General Public License as published by
+;;; the Free Software Foundation; either version 3, or (at your option)
+;;; any later version.
+
+;;; This file is distributed in the hope that it will be useful,
+;;; but WITHOUT ANY WARRANTY; without even the implied warranty of
+;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+;;; GNU General Public License for more details.
+
+;;; You should have received a copy of the GNU General Public License
+;;; along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+(in-package :consfigurator.util.posix1e)
+(named-readtables:in-readtable :consfigurator)
+
+(define-foreign-library libacl (t (:default "libacl")))
+
+(use-foreign-library libacl)
+
+(define-error-retval-cfun () "acl_free" :int (obj_p :pointer))
+
+(define-error-retval-cfun (:failure-val (null-pointer))
+  "acl_get_file" :pointer (path-p :string) (type acl_type_t))
+
+(define-error-retval-cfun ()
+  "acl_set_file" :int (path-p :string) (type acl_type_t) (acl :pointer))
+
+(define-error-retval-cfun ()
+  "acl_get_entry" :int (acl :pointer) (entry-id :int) (entry-p :pointer))
+
+(define-error-retval-cfun ()
+  ("acl_get_tag_type" %acl-get-tag-type)
+  :int (entry-d acl_entry_t) (tag-type-p :pointer))
+
+(defun acl-get-tag-type (entry-d)
+  (with-foreign-object (tag-type-p 'acl_tag_t)
+    (%acl-get-tag-type entry-d tag-type-p)
+    (mem-ref tag-type-p 'acl_tag_t)))
+
+(defmacro with-acl-free ((aclvar aclcall) &body forms)
+  (with-gensyms (aclvar*)
+    `(let* ((,aclvar ,aclcall)
+            (,aclvar* (make-pointer (pointer-address ,aclvar))))
+       (unwind-protect (progn ,@forms) (acl-free ,aclvar*)))))
+
+(define-error-retval-cfun (:failure-val (null-pointer))
+  ("acl_get_qualifier" %acl-get-qualifier) :pointer (entry-d acl_entry_t))
+
+(define-error-retval-cfun ()
+  "acl_set_qualifier" :int (entry-d acl_entry_t) (qualifier-p :pointer))
+
+(defun acl-get-qualifier (entry-d type)
+  (with-acl-free (qualifier-p (%acl-get-qualifier entry-d))
+    (mem-ref qualifier-p type)))